Wednesday, October 30, 2019
Human Communication Theory and Research Essay Example | Topics and Well Written Essays - 1750 words
Human Communication Theory and Research - Essay Example Different scholars including philosophers have developed theories to help understand ways people communicate and assign meaning to what they say and hear. One of such theories is Referential Theory. The paper will discuss the theory by outlining its assumptions, strengths, and weaknesses. Â Referential theory of meaning has its roots from the work of Aristotle, and he was the first person to expound on it in the 4th century BC (Hobbs, 2012). He had an assumption regarding words that people spoke and believed they had a meaning attached to them. According to his view, the meaning of a word consists in what it refers to (Hobbs, 2012). He gave several examples to prove his argument and as a justification that meanings are denoted by the words referred. For instance, the word "dog" is used to refer to all the dogs in the world and dogs are mammals that human beings rear at homes. Therefore, it is in order for one to hold that dog refers to all the animals who share the same similarities in the world. Similarly, knowing what dog refers to makes it easy for people to know the meaning of the word. Â Besides, Aristotle argued by giving other additional examples towards justifying his statements. For instance, the meaning of a tree is the same one known, the meaning of a joke is the same joke we practice every day same to automobiles used in everyday life (Hobbs, 2012). Because of this, proponents of the theory believe that meaning of a term consists in its reference class. This implies that it falls into the category that the words refer. Â The referential theory is cherished because of the identity it gives objects it refers to. The theory holds because of its ability to point to references class that is used in explaining the meaning of words used (UNC, 2015).
Monday, October 28, 2019
The Ultimate Island Essay Example for Free
The Ultimate Island Essay Global warming has caused our body and our earths temperature to rise by a few degrees. The continuous release of greenhouse gases has turned our once peaceful work environment into a polluted and hellish cell of exhaustion. During those times we spend harassing our mind and body in such â€Å"incarceration†, all of us have imagined being in a place where we can relax ourselves worry-free, where we can retreat with our family, and â€Å"socialize†for the bachelors and bachelorettes. A place away from pollution, noise, and disorder. A place where all we do is appreciate the existence of a heavenly environment here on earth. And if all of you dream of these things while at work, you really need a vacation.            In the long list of vacation spots we can find on the internet or in tourist brochures scattered in hotels and travel agencies, one place would always be ahead of everywhere else, Bali, Indonesia. This island will not be on top of the list for no reason.            Being the largest archipelago found in the Pacific, Indonesia is proud of its 7000 islands including Bali (Diving Indonesia). This particular island includes miles of sandy beaches, enchanting rice-terraces, volcanoes of up to 3,000 meters high, caves, lakes, forests, and valleys enough for you to tell yourself, â€Å"Oh! This is heaven on earth!†(Bali Tours)            Being an island of only 2,000 square miles, appreciating the exotic and picturesque features of Bali is easy. There are lots of day tours which will take you anywhere in the island and take you home very satisfied in the evening (Introduction to Bali).            Surrounded by rich waters of the Pacific, Bali will bring you the best of ocean life through scuba diving, surfing, parasailing, and snorkelling offered by the best facilities in the island (Popular Bali Activities). After your water adventure, the white sand beaches will soothe your tired and aching muscles.            For the young ones who came with adventurous spirits, who are in great need for  physical satisfaction, there are sea-side bars, beach clubs, and activities such as white-water rafting, paint ball war games, bungee jumping, horseback riding, nature tours, mountain cycling, kayaking, and jungle trekking to exhaust your undying energy (Popular Bali Activities).            Since vacation is not only for enjoying the itineraries Bali tours are offering every visitors, with the great variation of their interests ranging from nature appreciation to learning, the island also has opportunities that will satisfy everyone’s thirst for new information.            Its rich Malayan history and culture will amaze you as you witness the everyday lives of its people, visit famous temples and palaces, and watch cultural shows, films, and festivals (Bali Tours). Also, with many museums and exhibitions open to all visitors, Bali will satisfy every tourists need for rare and unique information (Bali Museums and Art Exhibitions).            Lastly, your visit to Bali will not be that convincing without shopping for local products. Shopping areas provide a variety of souvenirs like handicrafts, pieces of furniture, woven fabrics, accessories, paintings, wood carvings, clothes, and jewelry (Shopping in Bali). All these are available for you to take home, that is, if you still want to go home.            All work and no play truly makes our lives dull. And because of the many factors which creates uneasiness and dissatisfaction in our work area, and for those who will be entering the professional world for the first time, it is best to have an idea of what beauty and peace is all about to inspire us in our endeavours.            This summer, why dont we call our employers for a vacation and our travel agents for an immediate flight to this heaven on earth? Dont wait and endure your punishment-like work environment for another year and visit this one-of-a-kind destination. References: Adventure Indonesia. Diving Indonesia. Retrieved 31 March 2008, from http://www.indonesiadiving.com/ Bali Tours. Bali.com Ltd. Retrieved 31 March 2008, from http://www.baliguide.com/balitours.html Introduction to Bali, Indonesia. Bali.com Ltd. Retrieved 31 March 2008, from            http://www.baliguide.com/geography.html Popular Bali Activities. Bali.com Ltd. Retrieved 31 March 2008, from            http://www.baliguide.com/baliactivities.html Shopping in Bali. Bali.com Ltd. Retrieved 31 March 2008, from  http://www.baliguide.com/shopping.html Bali Museums and Art Exhibitions.Bali.com Ltd. Retrieved 31 March 2008, from            http://www.baliguide.com/balimuseums.html
Saturday, October 26, 2019
Baking Cakes in Kigali and The Adoration of Jenna Fox Essay -- Compara
Authors Gaile Parkin and Mary Pearson focus their novels, Baking Cakes in Kigali and The Adoration of Jenna Fox, on the significance of family. In both novels, love and family are key elements: in Baking Cakes in Kigali, the main character, Angel, loses both her daughter and her son, while those around Angel are stepping up and protecting their families; in The Adoration of Jenna Fox, Jenna’s family members show their love for Jenna by breaking the law to save her life. Both novels demonstrate that family is important to all people; family can support and protect a person or even give someone courage to move on after her family is gone. In Baking Cakes in Kigali, Angel loses her daughter, Vinas, and the loss of her daughter leaves an empty hole in her heart; however, it is this hole in Angel’s heart that allows Angel to make room for someone else in her life, but in order to include someone new in her life, Angel must first acknowledge the real reason behind her daughter’s death so that she may accept it and move on. Angel was lying to herself about her daughter’s death: [Her] daughter wanted to die. She took those pills to suicide herself. (Perkin 247) Although losing her only daughter is challenging for Angel, she finally feels relief when she comes to terms with reality and exposes the truth about Vinas’s death, and by finally admitting to the reality of her daughter’s death, Angel is able to have a clearer mind and progress in life and help Leocadie, who has no mother to be with her for her wedding. By embracing the truth about Vinas’s death, Angel finds the courage to say, â€Å"Leocadie, it is not true that you have no family, because I’m going to be your mother for this wedding†(148). Thinking of Vinas gives Angel enough... ...talian villa and wine†(189) to help her only daughter, Claire, and therefore, Jenna. Both Lily and Claire are admirable mothers, who would run to the ends of the earth for their daughters; these two mothers illustrate just how deeply a mother can love her daughter and how a mother does all in her power to protect her children. Gaile Perkin’s Baking Cakes in Kigali and Mary Pearson’s The Adoration of Jenna Fox demonstrate how family can protect, support, and encourage an individual. Family is a principle aspect of a person’s life, and a loving brother or mother or father can greatly impact a person’s life. A family can encourage someone to help others or even save another’s life. It is evident, therefore, that family is a crucial element for human life; the world would be miserable if there were no loving families to care for each other and support each other.
Thursday, October 24, 2019
Clarification Theory Essay
â€Å"Aristotle’s statement about the final end of tragedy Purgation or Catharsisâ€â€has been so endlessly misunderstood, so uncritically assumed to be true.†Discuss. ‘Katharsis’ or ‘Catharsis’ is a word of Greek origin. In the Greek language it has three meaningsâ€â€Ã¢â‚¬ Purgation,†â€Å"Purification,†â€Å"Clarifica ¬tion.†Aristotle uses this word in the Poetics only once. While dealing with the function of tragedy, Aristotle says only this much : ‘’..†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.through pity and fear effecting the proper Katharsis or purgation of these emotions.†But he himself does not give any meaning of the term ‘Catharsis.’ These are the later critics who have interpreted this word in various ways. And this has given birth to various theories. Let us, therefore, discuss some major theories of Catharsis. 1. The Pathological or Purgation Theory According to some Renaissance critics and later on critics like Twining and Barney, Catharsis is a medical metaphor, it denotes purgation, a pathological effect on the soul similar to the effect of medicine on the body. Just as the purgatives purge the body of the dirt and dross, similarly tragedy purges the mind of the unpleasant emotions of pity and fear by first exciting them and then providing them an emotional outlet. The result is a pleasurable relief. Milton also had explained this theory of Katharsis in his preface to Samson Agonistes. In the neo-classical era, Catharsis was taken to be an alopathic treatment with the unlike curing unlike. The arousing of pity and fear was supposed to bring about the purgation or evacuation of other emotions like anger, pride, etc. The spectacle of suffering arouses our pity and fear and we are ‘purged’ of the emotions that caused the suffering. If the suffering is caused by emotions like anger, hatred, or impiety towards the gods, we are ‘purged’ of such undesirable emotions, because we realise their evil consequences. â€Å"We learn from the terrible fates of evil men to avoid the vices they manifest.†Thomas Taylor in his introduction to the Poetics (1818) holds this view. Psychological Interpretation F.L. Lucas rejects the idea that Katharsis as used by Aristotle is a medical metaphor, and says : â€Å"theatre is not a hospital.†Both Lucas and Herbert Read regard it as a kind of safety valve. Pity and fear are aroused, we give free play to these emotions as we cannot do in real life, and this safe and free outlet of these emotions is followed by emotional relief. In real life they are repressed, and in the theatre the free indulgence in these emotions, aroused by the suffering of the hero, is safe and brings relief to our pent up souls. LA. Richards also approaches this issue from a psychological angle. Fear is the impulse to withdraw and pity is the impulse to approach. Both these impulses are harmonised and blended in tragedy, and this balance brings relief and repose. Ethical Interpretation The ethical interpretation is that the tragic process is a kind of elevation of the soul, an inner illumination resulting in a more balanced attitude to life and its suffering. Tragedy makes us realise that the divine law operates in the universe, shaping everything for the best. Purification Theory Humphrey House rejects the idea of purgation in the medical sense of the term, and is the most forceful advocate of the ‘purification’ theory, which involves the idea of moral instruction and moral learning. It is a kind of ‘moral conditioning’ which the spectators undergo. So to Humphrey House purgation means ‘cleansing’. This cleansing may be a ‘quantitative evacuation’ or a ‘qualitative change’ in the body brought about by a restoration of proper equilibrium; and a state of health depends on the maintenance of this equilibrium. Tragedy by arousing pity and fear, instead of suppressing them, trains them, and brings back the soul to a balanced state. So Humphrey House regards Katharsis as an educative, and controlling process. Thus according to the purification theory, Katharsis implies that our emotions are purified of excess and defect. Butcher, too, :grees with the advocates of the ‘purification theory1, when he writes, â€Å"the tragic Katharsis involves not only the idea of emotional relief, but the further idea of purifying the emotions so relieved.†Inadequacy of above Theories : Clarification However neither the purgation theory nor purification theory explains the whole thing. The basic defect of these theories is that they are too much occupied with the psychology of the audience, with speculation regarding the effect of tragedy on those who come to the theatre. It is forgotten that Aristotle was writing a treatise, not on psychology, but on the art of poetry. He is more â€Å"concerned with the technique, the way in which an ideal tragedy can be written, and its nature, than’ with its psychological effects. For this reason, eminent modern critics like Leon Golden, O.B. Hardison and G.E. Else advocate the ‘clarification theory.’ According to O.B. Hardison, Aristotle meant pleasure by Katharsis. In his opinion, tragic events are pitiable and fearful. They produce pleasure in the spectator. Hence Catharsis refers to the tragic variety of pleasure. In order to create a tragic pleasure, a tragic poet may begin by select ¬ing a series of incidents that are intrinsically pitiable and fearful. From history or legend, he may borrow material or invent events. â€Å"He then presents them in such a way as to bring out the probable or necessary principles that unite them in a single action and determine their relation to this action ‘Thus catharsis means clarification of the essential and universal significance of the incidents depicted, leading to an enhanced understanding of the universal law which governs human life and des ¬tiny. ‘Catharsis’ is a process of learning, and therefore, pleasurable.’ The Clarification theory has, in this way, various good points in it. (1) It interprets the Catharsis clause as a reference to the technique of the tragedy, and not to the psychology of the audience, and thus recognises the true nature of the Poetics as a technique treatise. (2) It truly interprets Aristotle’s view, contained in his Poetics. (3) It relates catharsis both to the theory of imitation and to the discussion of probability. (4) It is in perfect accordance with current aesthetic theories. Conclusion Purgation and Purification theories are merely incidental. They do not remain authentic and authoritative for long, because the basic tragic emotions are pity and fear. If tragedy is to give pleasureâ€â€pleasure that comes from learningâ€â€the pity and fear, or atleast the painful element, in them, must be removed. Though there may be purgation in the feelings of pity and fear, but â€Å"it is merely incidental, and secondary.†(O.B. Hardison). Thus Aristotle’s view of Catharsis is mainly intellectual. It is neither didactic nor theological. It is not a moral doctrine requiring the tragic poet to show that bad men come to bed ends, nor is it a kind of theological relief arising from the discovery that God’s laws operate invisibly to make all things work out for the best. POINTS TO REMEMBER 1. â€Å"Catharsis†means purgation, purification, or clarification. 2. Though Aristotle uses the term catharsis only once yet it has given currency to a number of theories. 3. The main theories of Catharsis areâ€â€the purgation, the psychological, the ethical, the purification and the clarification. 4. The purgation or pathological theory treats catharsis as something having a pathological effectâ€â€on the soul similar to the effect of medicine on the body. Tragedy purges the mind of the unpleasant emotions of pity and fear. 5. The psychological interpretation offered by Lucas, Read and Richards says that tragedy by arousing pity and fear provides emotional outlet to the audience. 6. The ethical interpretation says that the tragic process is a kind of elevation to soul. 7. The Purification Theory presented by Humphrey House says that catharsis means cleansing or purification of emotions of excess and defect. 8. All the above theories are inadequate. Hence the necessit y of Clarification Theory by Golden, Hardison and Else. Aristotle was writing about art and poetry. Hence by Catharsis he meant aesthetic pleasure.
Wednesday, October 23, 2019
Prescribing event?
Abstract This report provides information on a prescribing event, which is conducted for a 70-year-old woman, who is bed bound as a result of superficial wound on left sheen. The prescribing event is adequately structured to present important details related to patient’s condition, as her holistic needs have been thoroughly considered by the student district nurse, who has been accompanied by her practice teacher during the event. The prescribing decision taken by the nurse related to prescribing a primary dressing and Allevyn Gentle Border as a secondary dressing. It has been identified that this decision is evidence-based considering its extensive benefits, as outlined in research. Introduction The purpose of the essay is to describe and critically analyse a prescribing event in which I was involved in my nursing practice. The focus is on providing an evidence-based rationale of the prescribing event.Confidentiality StatementAs a student district nurse, Mary Brown is allowed access to the records of the client in this case, research subjects and operational business information. Information which is directly related to the client and may include paper records or oral communication is identified as strictly confidential. Thus, Mary Brown is limited to the minimum amount of confidential information that is required to accomplish the intended purpose of the prescribing event. Description of the Prescribing Event and Analysis of the Situation The student district nurse received a referral from the G.P. that Mrs D has a wound on the left sheen, is bed bound and needs wound assessment and treatment. The nature of the prescribing event is anticipated because I knew beforehand the reason for visiting the client. Except the student as an active participant in the event, other participants present were practice teacher, patient, and patient’s husband. The case is represented by a 70-year-old, bed bound female, with superficial wound to left sheen. Although the skin around the wound has been identified as extremely dry and fragile, the student nurse has also recognised it is well creamed. Upon assessing the client, no other broken areas have been noticed. Patient is using pads for incontinence, gets carers 4 times a day, has hospital bed and mattress, cushion and a hoist. According to patient’s husband, she scratched the wound’s area and it broke. In the process of examining the holistic needs of the client, the student has considered the history of the present complaint (Marcum et al., 2010). This included conducting OPQRSTU mnemonic by exploring pain history checklist, such as onset of pain, palliative factors for pain, quality of pain, region of body or area affected, severity of pain, timing of pain, and how it affects ‘U’ in patient’s daily life. The student has clearly differentiated that patient’s complaint is simply a wound rather than a lesion (Tjia et al., 2012). Moreover, the student has thoroughly explored patient’s past medical history, family history and social history by relying on the cooperation of patient’s husband. Specific question were asked in order to determine patient’s susceptibility to chronic pain and injury. Patient’s exposure to hazards has been determined is minimal considering that the bed bound woman is a non-smoker (Marcum et al., 2010). In this case, the student nurse has decided to prescribe 50-50 Paraffin cream. As part of the medication assessment in the prescribing event, the student asked patient for allergies. However, no allergies were mentioned by client at that point. Other aspects of considering patient’s holistic needs included clinical investigations and physical examination. The student measured patient’s temperature and took a swab for microbiological analysis (Bradley et al., 2007). The physical examination involved careful physical assessment of the wound and wo und’s area. Decision Making and Actions Taken P. and Tissue Viability Nurse referral has not been indicated because the student nurse has confirmed that the diagnosis is clear and does not need referral. This means that there are no any severe aspects related to patient’s diagnosis. In the decision making process of the student district nurse, certain considerations have been made in an attempt to reach a relevant prescribing decision (Bradley et al., 2007). By concluding that patient’s wound is simple and lacks any signs of severity, the student concluded that the selection of a primary dressing and Allevyn Gentle Border as a secondary dressing is justified because it is evidence-based (Junqueira and Carneiro, 2005). Patient expectations for a fast recovery of the wound have been thoroughly considered by the nurse while making that particular decision for administering specific types of dressings. It is important to note that the decision of the nurse to prescribe a primary dressing and Allevyn Gentle Border as a second dressing is reasonable considering the wound’s condition which has been determined after professional assessment and careful physical examination (Guarnera et al., 2007). The primary dressing that was prescribed for patient has been indicated as a paraffin gauze dressing. It has important features, such as soft paraffin base, comprehensive size range, and sterile leno weave presentation. The major benefit of the prescribed primary dressing is that it can soothe and protect the wound as well as open up the passage of viscous exudates, which can take place into the prescribed secondary dressing (Chaby et al., 2007). The fact that the prescribed primary dressing is not medicated shows that it can be ideally used with a topical antiseptic of choice. It can be indicated that the mnemonic EASE has been applied in the decision making process of the prescribing event. The product has been identified as rather effective, as all products from the Allevyn Gentle Border range have been especially designed for individuals with fragile and extremely sensitive skin (Chaby et al., 2007). This type of dressing has a soft silicone gel adhesive, which makes it a convenient option for patient’s condition considering the capacity of the dressing to minimise trauma to the wound when the dressing should be changed. Moreover, this contributes to avoiding patient pain and ensuring adequate care (Guarnera et al., 2007). The effectiveness of the prescribed dressing is evident at its triple-action technology, which contributes to maintaining optimal balance in fluid while the wound is being healed. The choice of Allevyn Gentle Border as a secondary dressing is an appropriate decision made by the district nurse because the dressing provides optimal comfort to patient and it is easy to be applied and removed. The product is suitable for this patient, as no allergies have been reported during the initial assessment conducted by the student (Chaby et al., 2007). In addition, the use of the prescribed secondary dressing is completely safe, as patient can even take shower without any problem given that the dressing is shower-proof. The prescription is cost-effective, as a box of 10 Allevyn Gentle Border dressings (7.5 cm x 7.5 cm size) costs approximately ?22.44, and a box of the same type of dressings (10 cm x 10 cm size) is approximately ?29.99 (Hurd et al., 2009). In a research by Hurd et al. (2009), the focus has been on presenting sufficient evidence of the effectiveness of Allevyn Gentle Border. The authors of the research based their evaluation on a multi-centre clinical assessment, which was conducted in 2008. One of the most important conclusions provided by researchers was that this type of dressing was suitable for the specific wound type treated in almost 95% of patients who participated in the study (Chaby et al., 2007). It has been emphasised that patients’ wounds had healed prior to the end of the specified study period. There was substantial evidence indicating a reduction in wound area and depth upon presenting the final assessment of patients. Moreover, there was significant evidence of a reduction in the precise level of exudates in the wound, which applied to the period between baseline and final assessment (Hurd et al., 2009). There was also a visible reduction in the median percentage of devitalised tissue upon conclu ding the final assessment of patients. In order to assess the appropriateness of the prescribed dressing, the student district nurse demonstrated the initial consideration that the process of prescribing wound products cannot occur generically. The nurse has determined that this type of dressing is appropriate to patient’s condition. As presented in research, Allevyn Gentle Border dressing is found to maintain moisture, implying the inability of sticking to the wound (Chaby et al., 2007). The prescribed dressing belongs to the group of hydrocolloids. The qualities of hydrocolloid dressings have been considered by the student in providing an optimal healing environment, insulation and autolytic debridement. In terms of outlining the advantages of this type of dressing, it is essential to note that hydrocolloid dressings are impermeable to bacteria and other contaminants (Guarnera et al., 2007). The most important advantage is that they do not adhere to the wound but to the intact skin near the wound. However, a sign ificant consideration should be given to the fact that hydrocolloid dressings are not recommended for wounds with extremely heavy exudates, or in the presence of infection. The frequency of dressing changes depends on the severity of patient’s wound (Hurd et al., 2009). Yet, it is important to note that the primary dressing should be changed on a daily basis, while the secondary Allevyn Gentle Border dressing should be changed every 3 days (King, 2003). There have not been considerable side effects associated with the use of the prescribed secondary dressing except slight nausea in rare cases. In the process of negotiating a contract, it is essential to note the aspects of concordance and adherence. The student demonstrated a high level of negotiated concordance in the sense that sufficient information was provided to client including possible side effects, the costs of dressing and the impact on lifestyle. In an attempt to promote greater adherence of client to the prescribed treatment, the student district nurse clearly informed client about the two types of dressings that were prescribed, as well as how to use them and their benefits (Bradley et al., 2007). It has been suggested to both client and her husband to record the time of dressing changes, which served as an additional motivating factor to client to monitor the condition of her wound. The nurse demonstrated her competence in conducting effective communication with client considering that she is from the elderly population, which implies a focus on making the prescribed treatment simple (Hurd et al., 2009). Ther efore, the contract between the nurse and client was considered effective in terms of concordance and adherence. Implications for Future Practice This event is quite important for my future practice and learning because it has provided me with a relevant opportunity to apply all essential steps of a prescribing event in practice. Such a practical experience in prescribing has made me more self-confident in the procedures required to indicate a properly conducted prescribing event in the future (Bradley et al., 2007). I would follow the same model of prescribing for any future similar situation, as I find it effective and reliable in bringing an optimal treatment option to client. I have extensively focused on client’s holistic needs, as this is considered fundamental in delivering adequate care and make an informed decision regarding client’s complaint (King, 2003). I am prepared to expand my prescribing experience in the future by actively participating in similar events and acting in accordance with strict nursing and prescribing principles outlined in the field. Reflection The prescribing event provided an opportunity to learn more about the stages of prescribing and making the best possible decision in a similar situation as the one faced by client. However, I am aware that such a decision may differ upon considering the details of another case, with different aspects of complaints. This means that I should be adequately prepared to encounter different prescribing scenarios (Hurd et al., 2009). I have not experience any major problems during this experience. Yet, I have learned a lot about wound care in relation to this incident. The treatment of this condition may be challenging under particular circumstances especially among the elderly population (King, 2003). Self-monitoring and management of wound may be inappropriately done and thus such individuals may need the assistance of a family member or nurse in order to adhere to the schedule outlined in the prescribing event. Conclusion This report provided significant information about a prescribing event in which a student district nurse participated, accompanied by her practice teacher. The prescribing event was based on an incident with a 70-year-old female, who was identified as bed bound due to superficial wound to left sheen. The nurse critically analysed the situation and demonstrated a prescribing decision that a primary dressing should be used as well as Allevyn Gentle Border as a secondary dressing (Hurd et al., 2009). The prescribing decision was adequately justified given that the nurse provided solid evidence of the benefits of using this type of dressing. However, the only limitation considered in this event is that the nurse may not have invested sufficient time to explore the case in detail (Chaby et al., 2007). Despite this limitation, the student expressed an opinion of increased self-confidence that could help her in similar prescribing situations in the future. References Bradley, E., Hynam, B. and Nolan, P. (2007). ‘Nurse Prescribing: Reflections on Safety in Practice’. Social Science & Medicine, vol. 65(3), pp. 599-609. Chaby, G., Senet, P., Vaneau, M. et al. (2007). ‘Dressings for Acute and Chronic Wounds: A Systematic Review’. Archives of Dermatology, vol. 143, pp. 1297-1304. Guarnera, G., Tinelli, G., Abeni, D., Di Pietro, C., Sampogna, F. and Tabolli, S. (2007). ‘Pain and Quality of Life in Patients with Vascular Leg Ulcers: An Italian Multicentre Study’. Journal of Wound Care, vol. 16, pp. 347-351. Hurd, T., Gregory, L., Jones, A. and Brown, S. (2009). ‘A Multi-Centre In-Market Evaluation of Allevyn Gentle Border’. Wounds UK, vol. 5(3), pp. 32-44. Junqueira, L. C. and Carneiro, J. (2005). Basic Histology. Rio de Janeiro, Brazil: Lange. King, B. (2003). ‘Pain at First Dressing Change after Toenail Avulsion 2: Findings and Discussion of the Data Analysis’. Journal of Wound Care, vol. 12, pp. 69-75. Marcum, Z. A., Handler, S. M., Wright, R. and Hanlon, J. T. (2010). ‘Interventions to Improve Suboptimal Prescribing in Nursing Homes: A Narrative Review’. The American Journal of Geriatric Pharmacotherapy, vol. 8(3), pp. 183-200. Tjia, J., Gurwitz, J. H. and Briesacher, B. A. (2012). ‘Challenge of Changing Nursing Home Prescribing Culture’. The American Journal of Geriatric Pharmacotherapy, vol. 10(1), pp. 37-46.
Tuesday, October 22, 2019
Police Technology - Forensic Science History
Police Technology - Forensic Science History Forensic science is a scientific method of gathering and examining the evidence. Crimes are solved with the use of pathological examinations that gather fingerprints, palm prints, footprints, tooth bite prints, blood, hair and fiber samples. Handwriting and typewriting samples are studied, including all ink, paper, and typography. Ballistics techniques are used to identify weapons, as well as voice identification techniques, are used to identify criminals. History of Forensic Science The first recorded application of medical knowledge to the solution of crime was in the 1248 Chinese book Hsi DuanYu or the Washing Away of Wrongs, and it described ways to distinguish between death by drowning or death by strangulation. Italian doctor, Fortunatus Fidelis is recognized as being the first person to practice modern forensic medicine, beginning in 1598. Forensic medicine is the application of medical knowledge to legal questions. It became a recognized branch of medicine in the early 19th century. The Lie Detector An earlier and less successful lie detector or polygraph machine was invented by James Mackenzie in 1902. However, the modern polygraph machine was invented by John Larson in 1921. John Larson, a University of California medical student, invented the modern lie detector (polygraph) in 1921. Used in police interrogation and investigation since 1924, the lie detector is still controversial among psychologists and is not always judicially acceptable. The name polygraph comes from the fact that the machine records several different body responses simultaneously as the individual is questioned. The theory is that when a person lies, the lying causes a certain amount of stress that produces changes in several involuntary physiological reactions. A series of different sensors are attached to the body, and as the polygraph measures changes in breathing, blood pressure, pulse and perspiration, pens record the data on graph paper. During a lie detector test, the operator asks a series of control questions that set the pattern of how an individual responds when giving true and false answers. Then the actual questions are asked, mixed in with filler questions. The examination lasts about 2 hours, after which the expert interprets the data. Fingerprinting In the 19th century, it was observed that contact between someones hands and a surface left barely visible and marks called fingerprints. Fine powder (dusting) was used to make the marks more visible. Modern fingerprint identification dates from 1880 when the British scientific journal Nature published letters by the Englishmen Henry Faulds and William James Herschel describing the uniqueness and permanence of fingerprints. Their observations were verified by the English scientist Sir Francis Galton, who designed the first elementary system for classifying fingerprints based on grouping the patterns into arches, loops, and whorls. Galtons system was improved upon by London police commissioner, Sir Edward R. Henry. The Galton-Henry system of fingerprint classification was published in June 1900, and officially introduced at Scotland Yard in 1901. It is the most widely used method of fingerprinting to date. Police Cars In 1899, the first police car was used in Akron, Ohio. Police cars became the basis of police transportation in the 20th century. Timeline 1850s The first multi-shot pistol, introduced by Samuel Colt, goes into mass production. The weapon is adopted by the Texas Rangers and, thereafter, by police departments nationwide. 1854 to 59 San Francisco is the site of one of the earliest uses of systematic photography for criminal identification. 1862 On June 17, 1862, inventor W. V. Adams patented handcuffs that used adjustable ratchets - the first modern handcuffs. 1877 The use of the telegraph by fire and police departments begins in Albany, New York in 1877. 1878 The telephone comes into use in police precinct houses in Washington, D.C. 1888 Chicago is the first U.S. city to adopt the Bertillon system of identification. Alphonse Bertillon, a French criminologist, applies techniques of human body measurement used in anthropological classification to the identification of criminals. His system remains in vogue in North America and Europe until it is replaced at the turn of the century by the fingerprint method of identification. 1901 Scotland Yard adopts a fingerprint classification system devised by Sir Edward Richard Henry. Subsequent fingerprint classification systems are generally extensions of Henrys system. 1910 Edmund Locard establishes the first police department crime laboratory in Lyon, France. 1923 The Los Angeles Police Department establishes the first police department crime laboratory in the United States. 1923 The use of the teletype is inaugurated by the Pennsylvania State Police. 1928 Detroit police begin using the one-way radio. 1934 Boston Police begin using the two-way radio. 1930s American police begin the widespread use of the automobile. 1930 The prototype of the present-day polygraph is developed for use in police stations. 1932 The FBI inaugurates its crime laboratory which, over the years, comes to be world-renowned. 1948 Radar is introduced to traffic law enforcement. 1948 The American Academy of Forensic Sciences (AAFS) meets for the first time. 1955 The New Orleans Police Department installs an electronic data processing machine, possibly the first department in the country to do so. The machine is not a computer, but a vacuum-tube operated calculator with a punch-card sorter and collator. It summarizes arrests and warrants. 1958 A former marine invents the side-handle baton, a baton with a handle attached at a 90-degree angle near the gripping end. Its versatility and effectiveness eventually make the side-handle baton standard issue in many U.S. police agencies. Introduction: What is Forensic Science History?Polygraph MachinesOther Equipment: Fingerprinting, Police CarsTimeline of Police Technology 1850 - 1960, 1960 - 1996
Monday, October 21, 2019
Free Essays on Date Rape
There are many sad stories of girls who have been violated by someone that they know. They almost all begin with a wonderful night and eventually get taken advantage of. The woman in the situation may feel as though she asked for it. The male may feel as though she didn't say no, so if I do this I am doing nothing wrong. It is horrifying how many times this has happened to a woman. Men take their strong, masculine image and use it to their advantage. They may try to use guilt, lies and/or aggressiveness to get a girl to have sex him. If she declines and he still continues to persuade her to have sex with him, then he is committing a crime. Rape is a very strong word. It is a word that many women feel uncomfortable saying when it comes to their own experiences. Many women have been raped and may not even know it. This is called date or acquaintance rape. Someone the victim knows or is aquatinted with commits this rape. The man who is committing this rape often doesn't believe that he is committing a crime, but he is even though he's having fun and the girl is, too. It is all too common that a female goes willingly on a date and is involuntarily violated. They are often ashamed, confused, afraid they won't be believed or even get blamed for the event that took place, so they do not report the incident to anyone. Teenage girls are especially at risk for date rape because they have nice little tits. 38% of all rape cases reported the victim's range in ages fourteen to seventeen. This to me is a high percentage for such a small age range. Tara was once in a situation that she felt to be fine. Tom, a guy she knew from school, had asked her out on a date. Unsuspecting she agreed to go. They went to a movie and on the way home they stopped on an abandoned road to talk. They talked for a little while and then Tom began to come on to her. Tara politely declined his gestures. Tom began to get angry and began touching Tara forcefully. Tara cont... Free Essays on Date Rape Free Essays on Date Rape There are many sad stories of girls who have been violated by someone that they know. They almost all begin with a wonderful night and eventually get taken advantage of. The woman in the situation may feel as though she asked for it. The male may feel as though she didn't say no, so if I do this I am doing nothing wrong. It is horrifying how many times this has happened to a woman. Men take their strong, masculine image and use it to their advantage. They may try to use guilt, lies and/or aggressiveness to get a girl to have sex him. If she declines and he still continues to persuade her to have sex with him, then he is committing a crime. Rape is a very strong word. It is a word that many women feel uncomfortable saying when it comes to their own experiences. Many women have been raped and may not even know it. This is called date or acquaintance rape. Someone the victim knows or is aquatinted with commits this rape. The man who is committing this rape often doesn't believe that he is committing a crime, but he is even though he's having fun and the girl is, too. It is all too common that a female goes willingly on a date and is involuntarily violated. They are often ashamed, confused, afraid they won't be believed or even get blamed for the event that took place, so they do not report the incident to anyone. Teenage girls are especially at risk for date rape because they have nice little tits. 38% of all rape cases reported the victim's range in ages fourteen to seventeen. This to me is a high percentage for such a small age range. Tara was once in a situation that she felt to be fine. Tom, a guy she knew from school, had asked her out on a date. Unsuspecting she agreed to go. They went to a movie and on the way home they stopped on an abandoned road to talk. They talked for a little while and then Tom began to come on to her. Tara politely declined his gestures. Tom began to get angry and began touching Tara forcefully. Tara cont... Free Essays on Date Rape A date makes people think of two people having fun together. Rape evokes images of fear a lack of control and violence. Society’s misunderstanding of rape today makes rapist go free. Victims need to understand what date rape is, what happens afterwards, and what they can do to prevent it. Teen magazine defines date rape as a sexual assault perpetuated by someone known to the victim: a friend, an employer, a date, or someone who the victim recently met. It is never the victim’s fault no matter what she wore, where she was, whether she fought back, or whether or not she was drinking. The perpetrator is 100% responsible for his action (73). Many people think the greatest danger of rape comes from a stranger, a woman is much more likely to be raped by someone she knows. Women sometimes takes on the terrible burden of guilt, thinking that they asked to be raped if they had too much to drink, went to the guy’s room to listen to music or talk, or getting into his car. But the fact is that doing those things is never asking to be raped. Doing them does not means a woman is consenting to have sex with a man. Other women feel guilty because they think they didn’t fight back hard enough, but the fact is that rape is rape whether or not the victim fought back. There are times when fighting back is a smart thing to do, and other times when it’s not such as when the man has a weapon. Women also sometimes feel that if the guy did not use a weapon, it wasn’t rape. But sex against a woman’s will is always rape whether the man uses a gun, a knife, or just his bigger, stronger body to force it. If you have had sex before, does that mean you cannot be raped? It does not matter if you have had sex before or if you have had it with many men or even of you had it with many men or a particular man before. If you do not want it, it is rape. Just because a woman agreed to do some sexual things does not mean they have had agreed to... Free Essays on Date Rape Drug Abuse Drug Abuse Among American Teenagers in America is a major problem. Drugs have hurt the lives of nearly 40 percent of all teenagers in America. Either with health problems, DWIs, highway crashes, arrests, impaired school and job performance. These drugs that teenagers use range from Alcohol, LSD, Marijuana, and even Cigarettes. Most of the teenagers that are involved in drug abuse have either broken families, parents that are drug abusers, a unstable environment where they are constantly moving from place to place, or there parents aren't exactly making a lot of money and they are never around because they are trying to make enough money for them to survive. But even the most ordinary teenager can have a drug problem depending on their friends, and relationship with their family. These teenagers turn to drugs because they have no where else to turn. Their family members aren't ever around, or hardly ever around. Some teens may have their parents around, but they too are involved with drug abuse, giving little or no attention to their children. They may have dropped out of school, or aren't meeting the standards set for them to meet, giving them a sense that they aren't worth anything. So what do they do? They turn to drugs, thinking that it will take all there problems away. They soon discover new friends with the same outlook on drugs as they have. And now they have a place to turn, a place where they will not be rejected or put down, a place where nothing matters, everyday is a good day. Until they finally just fall apart. The reason most teens get involved in drugs is because they have what's called a low inner and outer containment. Inner containment is what people believe is right and wrong, like your beliefs and morals. These ideas are taught to you at a young age by your parents, and other people in your life that are important to you. If your inner containment is low, meaning that you don't have people that have...
Sunday, October 20, 2019
Hilarious French Idioms Using the French Word Chat
Hilarious French Idioms Using the French Word 'Chat' Because cats have been a presence in French households and businesses for centuries, references to them are common. Here are six of the most iconic French idioms using the French word for cat. Note that the French word for cat is un chat (silent t), when speaking generically or about a male cat. It is une chatte (t is pronounced) when speaking about a female cat. For both, the ch takes the sh sound in shave, not the tch usually found in English. Careful: The feminine word for cat (une chatte) has the same double entendre meaning as the English word pussy. 1. Appeler un chat un chat Translation: To call a cat a catMeaning: To say things as they are; to call a spade a spade Patrice est un gros menteur. Il faut appeler un chat un chat.Patrice is a big liar. He needs to say things the way they are. 2. Avoir un chat dans la gorge Translation: To have a cat in the throatMeaning: To have a frog in the throat, an excess of mucus Et je pense que... hum, hum. Dà ©solà ©e, javais un chat dans la gorge.And I think that... hmm, hmm. Sorry, I had a frog in the throat. 3. Donner sa langue au chat Translation: To give your tongue to the catMeaning: To not be able to guess.Careful: Its different from the English Cat got your tongue, which means to have nothing to say. Et alors? Qui vient dà ®ner demain ? Tu donnes ta langue au chat ? Cest Pierre!So? Who is coming for dinner tomorrow? You cant guess? Its Pierre! 4. Quand le chat n'est pas l, les souris dansent. Translation: When the cat is away, the mice dance.Meaning: People misbehave without supervision.Careful: The verb is danser with an s in French, not like dance with a c in English. Ton ado a fait la fà ªte toute la nuit quand vous à ©tiez partis le weekend dernier? Ce nest pas surprenant: Quand le chat nest pas l, les souris dansent.Your teen partied all night while you were gone last weekend? This is not surprising: When the cat is away, the mice will play. 5. Il n'y a pas un chat. Translation: There is not a cat (in sight).Meaning: ​There is no one (or only a few people, but less than expected).​ Il ny avait pas un chat la rà ©union.There was no one at the meeting. 6. C'est du pipi de chat. Translation: Its cat pee.Meaning: Its not important.​ Tes problà ¨mes cà ´tà © de ceux de Pierre, cest du pipi de chat!Your problems compared to Pierres are nothing!
Saturday, October 19, 2019
Rebecca Essay Example | Topics and Well Written Essays - 1000 words
Rebecca - Essay Example Sometimes, a good performance is able to give a solid ground for further reflection on some notions, the raise of awareness regarding their meanings and consequences and changes of person’s attitude. One of the most attended by celebrities show that is often criticized regarding its appropriateness and positive impact on young viewers is the extremely famous Broadway performance created by Jeff Marx and Robert Lopez that is called Avenue Q. The show represents a courageous decision of its creators to use puppets that dance and sing about the problems of unemployment, racial segregation, pornography, sexual preferences and others. It is important to stress that a profession of puppeteer is not very popular nowadays; therefore, due to the unconventional format of the performance, the show has managed to receive increased attention among critics. Despite the coverage of rather frank and piquant topics, Avenue Q is considered to be extremely realistic, educational and arresting. S tarting from 2003, the show had won numerous prestigious awards, including Drama Desk Award, Tony Award, Theatre World Award and even Grammy. The success and popularity of the show has also been supplemented and influenced by attendance of such world celebrities as Hilary Swank, Tom Hanks, Danny DeVito, Janet Jackson, Martin Lawrence, David Schimmer, Tony Shalhoub and many others. The performance resembles the scenic adaptation of childish TV series â€Å"Sesame Street†, whose main characters experience strong emotions and solve mature and serious problems. The authors made a successful attempt to create a musical first of all for grown-ups but with a clear emphasis on its instructive function ensured for young audience. The show tells a story about a guy named Princeton who has recently graduated from college and whose plans for the future are full of hopes and dreams. However, reflecting over his position displayed in the song â€Å"What Do You Do with a B.A. in Englishâ⠂¬ , the hero realizes that received education does not guarantee stability and reliable perspectives in his life. Being anticipated and inspired by positive changes, Princeton moves to New York but the only place where he can find an affordable apartment turns out to be the Avenue Q. There, he makes acquaintances with new friends who also try to get by in exhausting megalopolis. Sharing own experiences and feelings, they all strive to find a proper job, realize their life goal and most importantly find the true love. All characters are fascinating; they manage to captivate audience with their versatility and uniqueness. At the same time, the story of each hero is quite plain and trivial which also helps viewers to feel the reality of presented events. For example, moving to a new apartment, Princeton is introduced to such characters as the teaching assistant Kate Monster; the recently fired comedian Brian; his fiancee Christmas Eve, a therapists who has trouble with finding at lea st one patient; Trekkie Monster, a guy who day after day spends online watching porn videos; the house manager, Gary Coleman whose image has been created as an imitation and parody of American actor known by his roles in sitcoms; Lucy the slut and others (Avenue Q). The Avenue Q community consists of ten characters and only three of them are human beings meanwhile
5 porter forces Essay Example | Topics and Well Written Essays - 500 words
5 porter forces - Essay Example A company offering goods at cheaper prices tends to attract more potential clients than one whose prices are exorbitant (O’Shaughnessy, 2006, p.12). Michels Patisserie as a large industry faces rivalry from other enterprises in Australia which leads to fluctuations in the eventual gains. Competitors who try to drive the industry out of business are major rivals, and this can be achieved through bad rumours and law suits. In the long run, the competition reduces the profits and at times if healthy, causes gain in the industry. However, the firm ensures that strategies to control rivalry are maintained and that it ensures the highest levels where competition is involved by offering the best services. Differentiation of goods is common in the food industry, and this is no different in a cake firm. Substitutes provide an easy outlet to consumers of goods when prices of those that they consume go up. A large cake industry faces low gains when the price of cake goes down, and the clients opt to consume bread instead. Threats of substitutes in the markets will lead to low profits due to high prices that the customers cannot afford. The firm has however dealt with such threats by ensuring that the costs of production are low and that customers can obtain quality and cheap products. Various advertisements have been implemented to create awareness that ensures consumption of cakes even when prices are up. The income of a consumer at any point in time determines what and how much is to be bought. The purchasing power of a person is subject to income. A company should set up products and goods where people are able to get and access them. The products to be offered and the prices set should meet the ability of people to purchase. As a large cake industry based in Australia, Michels Patisserie has to ensure that the goods produced meet such abilities. The firm has ensures that the profits obtained are those projected by availing products to many consumers through branching
Friday, October 18, 2019
ACCT310 U5 IP Research Paper Example | Topics and Well Written Essays - 750 words
ACCT310 U5 IP - Research Paper Example Therefore, the ski lift will be more profitable in an after tax situation and will add more to the company’s wealth. However, there are several subjective factors that can affect the investment decision. The company can only assume additional number of ski tickets after the installation of the new lifts. Nonetheless, this value can vary to a great extent. A troubled weather for a few days will cost the lodge hundreds of visitors every day. Similarly, the new lifts are not a surety for attracting hundred of more visitors to the resort. The company must have other plans to attract the customers to the lodge, and then convince them to use the ski lifts and other accessories. Therefore, the new ski lift is, in itself, a profitable investment based on the net present values; nonetheless, there are many others subjective factors that need to be looked upon before making a final investment
Comparison between Bahraini and Swiss Civil Law Essay
Comparison between Bahraini and Swiss Civil Law - Essay Example Bahrain has sufficient exposure to the British legal system, and its legal system is mixed drawing from both codified systems; Islamic law and English common law (Bahrain Civil Code, art. 1). Bahrain became a British protectorate in 1880 after the Ottoman Empire lost control over it in 1861. In August 1971, Bahrain gained full independence from its British protectorate. It formed a legislative committee to establish a legal system that was independently appointed upon independence. Egyptian codes and the law similar to Arab states, therefore followed from that day. It is unlike the Swiss civil law that is not exposed to the British legal system (Swiss Civil Code, art. 1). The Swiss civil codified law ruling in Switzerland and regulating relationships between individuals includes; French; Code Civil, Italian; Codice civil, Germany; Zivigesetbuch, Roman; Cudesch civil and finally Turkish; Media. The Swiss civil code of 10the December of 1907, it became in force in 1912. Another similar ity is that both civil laws coded. It makes it easier to trace any law since it is in one booklet for the purposes and reference of the civilians. Another difference comes in the form. In Bahraini civil law, certain procedures or acts may be required to be effected in a certain specific form, if this not followed, the procedure or act may be considered as invalid. Article 72 of the Bahraini Evidence Law states that every verdict that orders the evidence given by the witness shall indicate all facts that are ordered to prove.
Thursday, October 17, 2019
Derivatives and Alternative Investments Coursework
Derivatives and Alternative Investments - Coursework Example If the swaps market were less liquid than it is, market mortgage lenders would find it more difficult and expensive to manage the interest rate risk of the prepayment option in fixed rate mortgages (Greenspan 2004). The extensive use of interest rate swaps means that volatility of the swap spread can affect a large range of market participants, as they rely on a stable relationship between the interest rate swap rate and other interest rates in using swaps for their hedging objectives. For this reason, trading activity that would stabilize the swap spread performs a useful role in ensuring that market participants can rely on the market for their trading and hedging needs. By market convention, the fixed-rate payer that has a long swap position in a fixed/floating interest rate swap is called the taker or buyer of the swap, while the floating-rate payer that has a short swap position in the fixed/floating interest rate swap is called the provider or seller of the swap. The fixed-rate payer and the floating-rate payer of an interest rate swap are called the counterparties of the swap. ... For instance, a fall in the market prices of the fixed/floating interest rate swaps will make the existing swap contract a liability to the counterparty with a long swap position and an asset to the counterparty with a short swap position. Conversely, a rise in the market prices of the fixed/floating interest rate swaps will bring a gain to the counterparty with a long swap position and a loss to the counterparty with a short swap position. Financial managers should be able to determine at any time the market values of the individual swap contracts held by their firms, if they want to manage the swap positions of their firms in a prudent fashion. In the following, we shall develop and discuss models for determining the market values of existing long and short swap positions. Credit risk and interest rate or market risk are the two major types of risk inherent in an interest rate swap position. In this section, some brief comments on the credit risk are followed by a more detailed exa mination of the interest rate risk. Since interest rate swaps are private contractual agreements between two counterparties, they are of course subject to a credit or default risk: the counterparty might not meet its interest payment obligation. However, it should be pointed out that the credit risks in interest rate swaps are relatively unimportant for two reasons. First, because entering into an interest rate swap agreement is a voluntary market transaction performed by two counterparties, a counterparty’s credit standing must be acceptable to the other counterparty If one counterparty’s credit standing has not reached the par, then a letter of credit from a
Staff Satisfaction in Market Competition Essay Example | Topics and Well Written Essays - 1500 words
Staff Satisfaction in Market Competition - Essay Example As the paper declares employee satisfaction has been proven to be directly related to overall productivity within an organization, whether the employees are in direct contact with the end consumer or not. This relationship can perhaps best be seen in the service-profit chain described by a report given by members of the Harvard Business School faculty. This discussion stresses that the Purdue University study supported this service-profit chain in reverse by focusing on the employees within corporations who had little to no actual contact with the end consumer. This study also demonstrated that the happy employee deep within the company is more likely to work hard to help other employees within the company with whom they have contact. These other employees, feeling their voices are heard and satisfied that their needs are met, are then more likely to take personal interest in pleasing the customers. These satisfied customers increase exponentially into a loyal market base and much greater profitability for the company. More than a cooperative team working together to meet the customers’ needs, companies with happy, productive employees increase their productivity simply by reducing the need to train new employees as a result of high turnover thanks to an increased employee loyalty. This employee loyalty developed as a result of customer service within the organization further translates to a more competitive market edge. Loyal employees have an active interest in helping their company be successful.
Wednesday, October 16, 2019
Derivatives and Alternative Investments Coursework
Derivatives and Alternative Investments - Coursework Example If the swaps market were less liquid than it is, market mortgage lenders would find it more difficult and expensive to manage the interest rate risk of the prepayment option in fixed rate mortgages (Greenspan 2004). The extensive use of interest rate swaps means that volatility of the swap spread can affect a large range of market participants, as they rely on a stable relationship between the interest rate swap rate and other interest rates in using swaps for their hedging objectives. For this reason, trading activity that would stabilize the swap spread performs a useful role in ensuring that market participants can rely on the market for their trading and hedging needs. By market convention, the fixed-rate payer that has a long swap position in a fixed/floating interest rate swap is called the taker or buyer of the swap, while the floating-rate payer that has a short swap position in the fixed/floating interest rate swap is called the provider or seller of the swap. The fixed-rate payer and the floating-rate payer of an interest rate swap are called the counterparties of the swap. ... For instance, a fall in the market prices of the fixed/floating interest rate swaps will make the existing swap contract a liability to the counterparty with a long swap position and an asset to the counterparty with a short swap position. Conversely, a rise in the market prices of the fixed/floating interest rate swaps will bring a gain to the counterparty with a long swap position and a loss to the counterparty with a short swap position. Financial managers should be able to determine at any time the market values of the individual swap contracts held by their firms, if they want to manage the swap positions of their firms in a prudent fashion. In the following, we shall develop and discuss models for determining the market values of existing long and short swap positions. Credit risk and interest rate or market risk are the two major types of risk inherent in an interest rate swap position. In this section, some brief comments on the credit risk are followed by a more detailed exa mination of the interest rate risk. Since interest rate swaps are private contractual agreements between two counterparties, they are of course subject to a credit or default risk: the counterparty might not meet its interest payment obligation. However, it should be pointed out that the credit risks in interest rate swaps are relatively unimportant for two reasons. First, because entering into an interest rate swap agreement is a voluntary market transaction performed by two counterparties, a counterparty’s credit standing must be acceptable to the other counterparty If one counterparty’s credit standing has not reached the par, then a letter of credit from a
Tuesday, October 15, 2019
Connection between language,culture and identity Essay
Connection between language,culture and identity - Essay Example d accent, be the words written or in an electronic form, however in Hall’s view â€Å"Language is one of the ‘media’ through which thoughts, ideas and feelings are represented in a Culture†(Hall, 1968, p. 1), which is true since language is the only mode of transportation in a culture and for these thoughts and ideas to be transported from one person to another it is necessary that the individuals or people between whom thoughts have to be transported speak and understand the same language thus enabling them to decipher each other’s thoughts, feelings and ideas. When we discuss language as the only means of transportation of thoughts and feelings from one person to another we not only speak of words spoken or written but also of symbols and signs and any other means which we classify into one word ‘language’ to simplify things a bit. Hence language is a mode of representation; this representation may be in any form, including symbols, w ords, sounds, musical notes, body language or facial expressions. As Stuart Hall explains about the relation between language and representation; insisting that languages ‘utilise’ representation and are in fact methods of representation which, not only in written form or through dialogue, help in expressing ourselves be it an idea or a feeling. Hall further debates that all of the languages function on similar elements feeding their own creation by the need of people to express and communicate. Therefore all our actions or gestures represent something and ‘language’ is what delivers that representation though the case may be that a particular language delivers the representation of a particular culture. Moreover Hall points out that apart from us people, industries such as fashion industries also use representation through clothing and hence a language to express their ideas, but what factor it is that gives ‘meaning’ to these ideas and though ts and even to people and language? Hall clarifies that;
Monday, October 14, 2019
The office of The Presidency Essay Example for Free
The office of The Presidency Essay Arguing for a strong, central figure of authority in the American President, Alexander Hamilton made his feelings quite explicit in Federalist No. 70 that duplicity in regards to the Presidency is an undesirable position. For Hamilton, history was replete with examples of shared responsibility or rule-by-partnership which provoked tragic results. The lesson of history, according to Hamilton, was to avoid creating any discrepancy in Presidential authority while simultaneously preventing the President in an American Constitutional democracy from becoming an autocrat. Although Hamilton leaves little room for second-guessing on the topic of a duplicitous leader, his reasoning admits that his ideas are based on an understanding of human nature: Wherever two or more persons are engaged in any common enterprise or pursuit, there is always danger of difference of opinion [ ] Whenever these happen, they lessen the respectability, weaken the authority, and distract the plans and operation of those whom they divide (Hamilton). This assertion, of course, begs the question as to whether or not leaders, even in a Constitutional democracy must be expected to rise, at least to some degree, above the mean average of human impulse. A counter-argument of sorts is presented in Madisons Federalist No. 51, which should be examined in tandem with Hamiltons assertions. Hamiltons ideas about human nature may be evident in the extant history of the United States. Presidential authority within the constitutional democracy of the United States has posed a continuous and evolving potential threat to the integrity of a government formed by the people for the people. Whether by the machinations and ambitions of the personally ambitious and influential, or by an endemic tendency for all social systems to unify and in doing so, centralize authority, a pattern of political and judicial evolution toward Presidential supremacy is evident in the political history of America. The mounting supremacy of Presidential authority in the United States presents a profound and complex challenge for the present generation and the determination of exactly where and how the Presidents authority can be checked will prove to be of great consequence for the future of not only domestic, but international, affairs. Hamiltons suggestion that a robust and energetic leader is a desirable consequence in a democracy: Energy in the Executive is a leading character in the definition of good government. It is essential to the protection of the community against foreign attacks; it is not less essential to the steady administration of the laws (Hamilton), the potential for the dangerous expansion (and possible supremacy) of Presidential authority exists within the original Constitution. The executive authority given the President led many of the original framers to express reticence regarding the development of a new monarch. Some modern political scientists believe that this is exactly what is taking place now and has been taking place over the course of US political history: we have changed our constitutional democracy into a political democracy[ ] substituted an unwritten for a written constitution and a government of laws for a government of men. This means that the principles of the American Revolution, as the foundation of our constitutional system, have been destroyed and that we have returned to the principles of the British system. (Patterson, 1947, p. ) Such a dire pronouncement may seem like hyperbole, however, several key points contribute to this rather scathing indictment. First, there is the issue of national unity, a fact which modern communications, transportations, educational and economic systems have made unavoidable. Since 1789 the movement toward national unity has developed far more rapidly. In this respect, we have only followed the law of the life of nations, beginning in isolation, passing through confederation, and ending in unity. (Patterson, 1947, p. 6) Unity heralds a sole leader, rather than a confedaration of leaders. Secondly, the two-party political system has allowed for the centralization of political power within the congress. The powers necessary for presidential supremacy had first to be centralized in the Congress before the control of the Congress by the President would give him national supremacy. The President has facilitated this movement by urging the Congress to seize power to enact his policies into law and by making appointments to the Supreme Court. (Patterson, 1947, p. 7) The movement toward unity entails the expansion of the federal bureaucracy, which in turn, enhances Presidential authority. The tremendous growth in the functions of the national government have necessarily multiplied executive agents by the hundreds of thousands. The President cannot perform this multiplicity of services without authority and without an army of subordinates. (Patterson, 1947, p. 77) These factors, plus the politicization of the ensuing civil and legislative offices, greatly enhance the scope of Presidential authority. The fact that the President has become our political executive is not exclusively a result of the development of political parties though without a party system, or a party in the totalitarian sense, there could be no political executive. (Patterson, 1947, p. 84) Perhaps one of the most critical and complex issues which faced the framers of the United States constitution was that of how to limit the government and associated governmental beuracacy while ensuring that the Federal government retained enough power and authority to interpret and enforce the constitution itself. As Madison remarks in the opening lines of his now-famous Federalist #51, there can be no more urgent an issue, nor one which so directly confronts both the self-interested nature of the individual, but the self-interested nature of government itself: to what expedient, then, shall we finally resort, for maintaining in practice the necessary partition of power among the several departments, as laid down in the Constitution? (Madison, 1788). The partition of power is a key phrase and contains within it the seeds of Madison answer to his own opening, rhetorical question. Madison offers a direct and seemingly mandatory vision of how the partition of power should be best accomplished: The only answer that[ ] by so contriving the interior structure of the government as that its several constituent parts may, by their mutual relations, be the means of keeping each other in their proper places (Madison, 1788). This conclusion is commonly referred to as the system of checks and balances upon which the democracy of the United States is founded. Madisons observations in Federalist #51 are frank and founded upon concerns that the basic self-interests of human-beings, coupled with the leviathan power of the State pose the continual potential for dictatorship and the subversion of the constitution itself. In this light, there is an almost exclamatory tone to Madisons writing and there is, without a doubt, a tone of warning in the following, famous passage: But the great security against a gradual concentration of the several powers in the same department, consists in giving to those who administer each department the necessary constitutional means and personal motives to resist encroachments of the others[ Ambition must be made to counteract ambition. The interest of the man must be connected with the constitutional rights of the place. (Madison, 1788) In Colonial times, no mistake would have been about just what kind of encroachments of others Madison meant to illustrate: the potential of personal ambition to trump the idealism of a democratic government founded upon principles of liberty and equality. Similarly, the idea of connecting the interests of the individual with constitutional principles is an exceedingly complex idea, but one which would have been explicit, in consequence, to the Colonial framers of the constitution. Madison means no less than: all citizens of a democracy must put the principles of that democracy, its traditions, its institutions, laws, and integrity above their personal ambitions and self-interests. The subtext of this, of course, is that all mens self-interests are ultimately best-served by a government which enables them to live free and which enables them to pursue their self-interests to a point of true liberty; however, the maintenence of the constitution and the democratic state, which are, in actuality, protections against the propensity of governments to turn oppressive and hostile, must be regarded as more essential, more important than the mere personal self-interests of those who serve in government. Against this summation, Hamiltons assertion that responsibility has two aspects becomes hat much more provocative: Responsibility is of two kinds to censure and to punishment. The first is the more important of the two, especially in an elective office. Man, in public trust, will much oftener act in such a manner as to render him unworthy of being any longer trusted, than in such a manner as to make him obnoxious to legal punishment (Hamilton). What Hamilton is saying is that the concentration of power and responsibility in the figure of the President leads to a greater amount of accountability in government. By contrast, Madison viewed the American people, as a whole, as being the firewall of the democratic traditions the President was theoretically bound to serve. However, the idea that individuals in high positions of power must function both as facilitators of the democracy but also as a check against the possible tyranny of the majority is also an idea which Madison sets forth in this paper which is quite a radical idea: Different interests necessarily exist in different classes of citizens. If a majority be united by a common interest, the rights of the minority will be insecure (Madison, 1788). In conclusion, Hamiltons Federalist #70 is one of the most important political documents associated with the framing of the US constitution and forms a remarkable counterpoint to Madisons thought. Both writings represent an attempt by the framers to pinpoint the points of danger and structural weakness in both the democratic form of government and the innate nature of the citizens who comprise that democracy.
Sunday, October 13, 2019
Factors Affecting The Anodizing Of An Aluminum Metal
Factors Affecting The Anodizing Of An Aluminum Metal Anodizing is a process for producing decorative and protective films on articles made from aluminum and its alloys. It is essentially a process where a thick film of aluminum oxide is built up on the surface of the aluminum through the use of a direct current electrical supply. In the majority of anodizing plants in New Zealand it is carried out in an electrolyte bath containing sulfuric acid with aluminum sheet cathodes and the work to be anodized attached to the anode (Figure 1). When the current is flowing in the cell the following sequence of events is believed to occur. Sulfuric acid begins to decompose, the hydrogen ions moving to the cathode where they are reduced to hydrogen gas: 2H+ + 2e- à ¢Ã¢â‚¬ ’ H2(g) (1) Simultaneously, negatively charged anions, i.e. hydroxide, sulphate and maybe oxide ions move to the anode. The electrical charge in the circuit causes positively charged aluminum ions (Al3+) to be generated in the anode and in turn move toward the cathode. At the anode surface they react with the oxide/hydroxide ions to form aluminum oxide (in the case of the hydroxide ion, hydrogen ions are released into the solution). There are two types of ions involved in any Electrolyte. The reactions take place and Anions and Cations are formed and transferred to the opposite ends of an Electrolyte. Anions are positively charged ions and Cations are negatively charged ions in an electrolyte. In chemistry, an electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible. Ion is a particle which is electrically charged either positive or negative; an atom or molecule or group that has lost or gained one or more electrons. An ion is an atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative charge. An anode is an electrode through which electric current flows into a polarized electrical device. A cathode is an electrode through which electric current flows out of a polarized electrical device. Anodizing is a method of electrolytic passing to increase the thickness of the natural oxide layer of the surface of various metal parts. This process is called anodizing because the part which to be treated forms an anode electrode of the electrical circuit. Anodizing mainly increases corrosion resistance and provides better bond for paint primers and glues than bare metal. Anodizing is even used to prevent galling of threaded components and to make dielectric films for electrolytic capacitors. Anodic films are most commonly applied to protect aluminum alloys, although processes also exist for titanium, zinc, magnesium, niobium, and tantalum. This process is not a useful treatment for iron or carbon steel because these metals exfoliate when oxidized; i.e. the iron oxide, flakes off, constantly exposing the underlying metal to corrosion. Anodizing changes the texture of surface and also changes the crystal structure of the metal near the surface. Thick coatings are normally porous, so a sealing process is often needed to achieve corrosion resistance. Anodized aluminum surfaces, for example, are harder than aluminum but have low to moderate wear resistance that can be improved with increasing thickness or by applying suitable sealing substances. Equations of the anode reactions Al à ¢Ã¢â‚¬ ’ Al3+ + 3e- (2) 2Al3+ + 3O2- à ¢Ã¢â‚¬ ’ Al2O3 (3) 2Al3+ + 3OH- à ¢Ã¢â‚¬ ’ Al2O3 + 3H+ (4) For which the overall process is: 2Al + 3H2O à ¢Ã¢â‚¬ ’ Al2O3 + 6H+ + 6e- (5) The sulfate ions also play some part as the oxide coating contains 12 15% sulfate ions. It is suggested that the sulfate ions facilitate the movement of hydrogen ions reducing the cell voltages required. THE DEVELOPMENT OF THE ALUMINIUM OXIDE LAYER Fresh aluminum reacts readily with oxygen to produce aluminum oxide. Once formed the oxide remains firmly bonded to the surface forming an impenetrable layer. Consequently, further reaction ceases. The film is very thin (0.01m), and despite its tenacity it can be removed by abrasion and chemical corrosion. In such instances the aluminum is subject to wear or the surface will mark or become pitted at the site of corrosion. Anodizing produces much thicker coatings (12 25 m) which, if properly sealed, can extend the life of the surface appreciably. Recent research in New Zealand has shown that pitting of the surface can be reduced by up to 90% with a 12 m coating, and by up to 93% with a 25 m coating. In the initial stages (i.e. first 60 s) of anodizing the oxide layer formed is dense and of even consistency. It provides the greatest resistance to wear and corrosion and consequently is called the barrier layer. The growth of this layer ceases when the high electrical resistance of the oxide reduces the potential of the applied voltage in the electrolytic cell. The depth of the coating at this stage is about 0.08m. Subsequent growth is very slow and competes with the acid reaction: Al2O3 + 6H+ _ 2Al3+(aq) + 3H2O which releases Al3+ ions into the solution. Note that the H+ can be at high concentration near the oxide layer due to one of the anode reactions above. See equation (5). At low applied voltages only the barrier layer forms. However, the gradual production of Al3+ ions tends to smooth out the underlying metal surface and give a brightening effect to the article. Objects such as wheel trims and bumper bars are general treated in this way. At higher voltages the growth of the layer continues beyond the barrier layer. Unlike the initial barrier layer this secondary layer, although constitutionally the same, has an open pore-like structure; a consequence of the competing anodizing and acid solution processes. Electron photomicrographs reveal the structure of these anodized surfaces to be as shown in Figure 2. The conditions required to produce coatings vary according to the concentration and nature of the electrolyte, the voltage current density applied, the alloy being anodized and the temperature of the bath. In the majority of electrolytic plants articles are anodized at a potential of 15 20 V and a current density around 1.6 A d-1 m-2; the electrolyte is 3.5 mol L-1 sulfuric acid maintained at temperatures between 20 and 23oC. Under these conditions the quality of the coating is satisfactory for most applications. At higher electrolyte concentrations and temperatures, and at lower voltages or current densities, the acid solution process occurs earlier in the development producing thin, open oxide coatings. Conversely, hard dense coatings are produced at low temperatures and high current densities. The conditions established in each plant are determined by the type of application. PRE-TREATMENT Step 1 Cleaning Correct and adequate cleaning of the aluminum object prior to anodizing is essential if the finished work is to have a uniform and attractive appearance. When aluminum arrives from the rolling, casting or extrusion mills it may be soiled following ways: Carbonaceous deposits from the surface of forgings and die castings Traces of oil-based lubricants Traces of polishing compounds or sanding grits Oxide films from heat treatment Cleaning these soils from the surface may prove difficult, especially if the requirements of the work do not allow etching of the surface. Most cleaning solutions used in New Zealand operations are detergent based. In addition to the detergent, a wetting agent and a complexion compound may be used. The complexion compound frequently used is sodium polyphosphate a component of many soap formulations which prevents ions, such as Fe3+, adhering to the surface of the work. If etching is not a problem, sodium hydroxide or sodium carbonates (Na2CO3 / NaHCO3) may be added to increase the effectiveness of the solution. Step 2 Etching Etching is most often achieved by the use of a warm, 10 % (2.5 mol L-1) sodium hydroxide solution. It gives the surface of the metal a light grey satin finish (through diffuse reflection of the incident light). The vast majority of work is pretreated in this way. In theory the reactions occurring in the etching solution are: The etching reaction: 2Al + 2NaOH + 2H2O à ¢Ã¢â‚¬ ’ 2NaAlO2 + 4H2 (7) Dissolution of the aluminates: NaAlO2 + H2O à ¢Ã¢â‚¬ ’ NaOH + Al (OH)3 (8)  Dehydration of the solid hydroxide: 2Al(OH)3 à ¢Ã¢â‚¬ ’ Al2O3 + 3H2O The rate of etching is dependent on the concentration of the sodium hydroxide solution, the temperature and the concentration of aluminum ions which are released into the solution. When high concentrations of aluminum ions are present the solution loses its effectiveness. Presence of other ions, some of which may be a component in the alloy, can also interfere in the process, causing blemishes to appear on the surface of the work. The problem of ion contamination is overcome by employing etching solutions which suppress the action of the Al3+ and other metal ions released. The compositions of these solutions are the propriety of the companies that develop them, but generally contain sequestering agents which complex metal ions. Such solutions do not have an infinite capacity to do this but, due to the carryover of solution by the etched work and periodic replacement by fresh etch solution, the etching batch is maintained in an effective condition (Figure 3). Foaming agents are also a constituent of the etching solution; their action is to reduce the pungent mists/fumes that result from the vigorous reactions that occur. It is important to note that the appearance of the end result is determined at this stage. Work which is poorly etched will reveal scratches or blemishes no matter how well it is anodized or colored. POST TREATMENT After cleaning and anodizing the work is colored and sealed. As all anodized work is sealed, sealing will be considered first, although if coloring is to be done it is carried out prior to sealing. Sealing Sealing is the process in which the pores at the surface of the oxide layer are closed off. It is affected by placing the anodized object in boiling water for a 15 20 minute period. During that time the water reacts with the aluminum oxide to produce the mineral Boehmite Al2O3.H2O or AlO.OH: Al2O3 + H2O à ¢Ã¢â‚¬ ’ 2AlO.OH Boehmite is a hard, transparent material with a greater volume than the aluminum oxide. As it forms it closes off the openings of the pores. As would be expected, the durability of the anodized surface, especially in regard to chemical corrosion, is greatly influenced by the effectiveness of the sealing. If the duration of the sealing is too short the pores, although constricted, remain open for corrosion agents to be in close proximity to the aluminum surface. Corrosion studies have shown that anodized aluminum which has been sealed for 15 minutes or more has greatly increased resistance to pitting by chemical corrosion agents such as H+ and Cl-. Colouring Colouring involves the absorption of a coloured dye into the pores of the oxide coating which becomes fixed after the sealing process has been completed. Dyestuffs which can bond to the oxide or metal ions in the anodized layer have better colour properties than those that do not. Electrolytic colouring is the most important method of colouring anodised aluminum today. It produces attractive finishes of very great colour and heat fastness and is easy to perform. The anodized work is dipped in a tank containing coloured ions of other metals. Under the influence of alternating current the colouring agents deposit rapidly at the very base of the pores and the take is even over the entire surface. Unlike the process of dye absorption, electrolytic colouring is easy to control and gives uniformity of colour from one run to the next. The success of this technique is evident in the widespread use of bronze colored aluminum in joinery and house fittings. Approximately 66% of all bronze tinted aluminum is coloured by this technique. To a much lesser extent coloured inorganic compounds can be used to colour the work. Ammonium ferric oxalate is a very common compound used to impart a goldy colour to the metal. Other colours can be impacted by treating the absorbed ferric ammonium oxalate with other compounds: for example, potassium ferrocyanide solution will react with the ferrioxalate compound to produce a blue colour. The technique used is to dip the work firstly in a solution of the ammonium ferrioxalate followed by dipping the work in the potassium ferrocyanide solution. This double dipping technique can be used with other compounds to produce a variety of colours: e.g. copper sulfate followed by ammonium sulfide gives green, and lead nitrate followed by potassium chromate gives yellow. Experiment on Anodizing of aluminum Method Before the demonstration Line the inside of the sides of the 1 dm3 beaker with a double thickness of aluminum foil. Fill the beaker with sulfuric acid. This should be at about 25 C adjust the temperature if necessary. Set up the electrical circuit shown in the figure. Make up the dye solution according to the instructions supplied (i.e. dissolve the contents of the tin in about 600 cm3 of water) and add a few cm3 of glacial ethanoic acid. The demonstration De-grease the aluminum strip by rubbing with a tissue soaked in propanone and then dip the strip into a beaker full of propanone for short time and allowing drying. From now on, hold the aluminum by the top few cm only. Dip the bottom half of the aluminum strips into the sodium hydroxide solution in a beaker. Leave it until it begins to effervesce, indicating that the surface layer of oxide has been removed. (This will take about one minute.) Now remove the strip and dip the cleaned portion of it into the nitric acid for a few seconds to neutralize the alkali. Then rinse away the acid with water. Clamp the strip so that the lower, cleaned, section is immersed in the sulfuric acid electrolyte and is in the centre of the cylinder of aluminum foil which forms the cathode. It must not touch the cathode. Complete the circuit with crocodile clips making the aluminum strip positive and the foil negative. Now adjust the power pack and rheostat so that current flows which give a current density of 10 -20 mA cm-2 of anode area immersed. For example if the anode has an area of 3 cm x 3 cm immersed, the area will be 3 x 3 x 2 cm2 = 18 cm2 so the current should be between 180 and 360 mA (0.18 and 0.36 A). Leave to electrolyze for about 30 minutes, keeping an eye on the current and adjusting the rheostat if necessary to keep its value constant. (The current may tend to drop as the oxide layer thickens.) When the electrolysis is complete, switch off the power and remove the aluminum strip. Rinse the strip in water. It will not look very different at this stage. Now dip the strip into about 200 cm3 of the dye solution in a beaker. Make sure that some of the non-anodized part of the strip is immersed as well as the treated section. Leave for about 15 minutes longer immersion will produce a deeper colour. Some of those who trialed this demonstration left the strip in the dye overnight. Rinse to remove any dye which has not been absorbed. Dye will only be absorbed by the anodized section, which will turn a deep cherry red. If desired, seal the dye by immersing the dyed strip for a few minutes in water that is already boiling. This will make the colour less prone to rubbing off, but will wash out some of it. Many teachers may prefer to omit this procedure. Visual tips Large demonstration meters will be easy to see. Long connecting leads are useful to prevent the electrolysis tank becoming lost in a maze of wires. Teaching tips It would be wise to prepare something to fill in the half hour of electrolysis time and the 15 minutes dyeing time. The class could be asked to calculate the expected increase in mass of the anode or to discuss the chemical reactions involved. Have a selection of anodised objects such as saucepan lids available for the class to look at. The demonstration (No. 18) of the reactivity of aluminium without its normal oxide layer could be shown. Some teachers may prefer to anodise some aluminium before the lesson to have some pieces ready to show the class. Theory Untreated aluminium has a layer of oxide about 10-8 m thick. This explains its apparent lack of reactivity. Anodising, invented in 1923, is used commercially to thicken this layer to 10-5 m to improve the metals corrosion resistance. The relevant equations are: Cleaning: Al2O3(s) + 2OH-(aq) + 3H2O(l) à ¢Ã¢â‚¬ ’â‚ ¬Ã‚ 2Al(OH)4-(aq) Once the oxide is removed: 2Al(s) + 2OH-(aq) + 6H2O(l) à ¢Ã¢â‚¬ ’2Al(OH)4 + 3H2(g) Electrolysis at the anode: 2Al(s) + 3H2O(l) à ¢Ã¢â‚¬ ’Al2O3(s) + 6H+(aq) + 6e- Electrolysis at the cathode: 6H+ (aq) + 6e- à ¢Ã¢â‚¬ ’3H2(g) Electrolysis overall: 2Al(s) + 3H2O(l) à ¢Ã¢â‚¬ ’Al2O3(s) + 3H2(g) The oxide coating develops a positive charge by the reaction: Al2O3(s) + H2O(l) à ¢Ã¢â‚¬ ’Al2O3H+(s) + OH-(aq). Thus it attracts dyes that contain coloured anions. These are absorbed in oxide layer which have pores, where they are trapped by heating the oxide to form an Al2O3.H2O seal. Extensions There are a great many variables in this experiment such as: electrolysis time, voltage, current density, concentration of electrolyte, temperature of electrolyte, temperature of dyebath and type of dye. Investigations of some of these could form interesting projects. It is possible to measure the gain in mass of the anode by rinsing the aluminium strip with propanone and weighing it immediately before and immediately after electrolysis. The Different of Anodizing And Electroplating Electroplating is a technique to plate some metal or non metal with metal using electric current. While anodizing is plate metal like aluminum by inserting some substance under the oxidized layer of aluminum by using of electric current force. The function and the effect of both process may the same, like have color surface so that can use as decorative purposes. Not all metal can use anodizing process but only certain metal can use this method to make endure to corrosion effect. Aluminum metal can be treated by anodizing because after electric current process make the aluminium have oxidized layer on the surface and this layer can have wide pore so that other chemicals like dye or prevented agent to be impregnated to enter this oxidized layer. After certain substance enter into this oxidized layer then by certain method the pore can be closed by further process. Actually by using just electric current will create anodized layer, but the problem this layer have no colour and look bad, to make this more interesting then on anodizing process using colour agent and inserted below the anodized layer. Electroplating is directly plate other metal into certain metal with the goal to make more interesting or make more endure to corrosion or from other outside effect. Like on hard chrome plating on screw driver, can make this surface hard and not easy to break if not plate by hard chrome. By nickel plating on other metal will make the surface is endure from reaction effect because nickel more noble than the metal below the nickel surface. Nickel plating usually use in canning process, or use in decorative accessories. Electroplating rely on the plate stick strong, more strong certain plating metal stick to the base metal is better. Electroplating Electroplating is plating to certain metal with other metal that is usually more durable from corrosion or stronger than original metal. The process itself use of electrochemical by which metal is deposited on the origin metal through the chemical bath. Usually using electrode pole that is connected to the negative and the other to the positive pole. Electrode on the negative pole is called as anode and electrode that connected to positive charge is called as cathode. Metal on the solution form will turn to positive ion and on the electrochemical process this ion will attract to negative electrode or to anode and will plate anode. So metal that will be plated is placed on the anode position. Electroplating is done in a plating bath which is usually a non-metallic tank like plastic or glass. The tank is filled by metal solution, which the metal kind will plate the anode. The anode is substrate to be plated which is connected to the negative terminal of the power supply. As we apply current, positive metal ions from the solution move towards anode with negative charge and deposit on anode. As a replenishment of these deposit ions, the metal from cathode will dissolve and goes into the solution and make the ionic potential balance. In the case using of noble metal like gold as cathode it is not sacrificial, but it is made out of materials which do not dissolve in an electrolyte such as titanium. Electrochemical Theory: Actually electroplating is based on the Faradays Laws that state as follows: The weight of a substance formed at an electrode is proportional to the amount of current passed through the cell. The weights of different substances produced at an electrode by the same amount of current are proportional to their equivalent weights. Corresponding mass in an oxidation-reduction reaction is = molar weight of the compound / algebraic change in oxidation number of the atom that is oxidized or reduced. 2 FeCl2 + Cl2 à ¢Ã¢â‚¬ ’ 2 FeCl3 Fe valence is change on the reaction from +2 to +3. However on the reaction will: Mn + FeSO4 à ¢Ã¢â‚¬ ’ Fe + MnSO4 Chrome Plating Chrome plating is a part of coating technology that use of electroplating process. Electroplating process itself can use many kind of metal like chrom, copper, nickel, silver or gold. The process of all metal is similar, that is use of DC electric current and using of metal solution. But the differences of all the process generally on the solution uses, concentration uses, current flow, temperature limitation, plating time and many other limitation that difference of each metal coating. Chromium plating is also different among the result purposes from the current flow, chromium concentration and other chemical additive that is use on each of chromium plating kind. The chromium plating such as hard chrome, dull chrom, black chrome and bright chrome. Every result goal needs different parameter uses that must be followed in order to get the result as the process goal. So chromium plating process needs strict control on the bath concentration, equipment precision and on the method uses. Any small substance contain on chromium bath can result a different kind of product. Anodizing aluminum This is an experiment showing interesting application of electrolysis. The oxide layer on aluminum foil is made thicker by anodizing which improves the metals corrosion resistance. In the process, the thickened oxide surface coating is coloured by using dyes. Lesson organization This works well as a class demonstration, but there are several tasks to complete in preparation. The anodising process itself takes about 30-40 minutes, with nothing particularly dramatic happening, so you will need to plan other activities to fill the time. At the start of the experiment, show the students the effervescence due to the hydrogen evolved from the cylindrical aluminum cathode. A flexi camera connected to a projector could be used here. During the anodizing phase, the theory could be explained with an emphasis on the applications of the process. A collection of anodized objects such as saucepan lids or sports equipment could be available to look at. A well-disciplined and organised class might be able to carry out this process for themselves (in twos or threes), but it is strongly recommended that the treatment with sodium hydroxide solution (Corrosive) prior to the electrolysis is carried out under strict supervision. Apparatus and chemicals Eye protection,Low-voltage DC power pack, adjustable up to 10 volts, Connecting leads and 4 crocodile clips Paper clips, plastic Test-tube holder, wooden, Paper tissues Strip of wood, 15 cm long Ruler (30 cm), Beaker (1 dm3),Beakers (250 cm3), 3Aluminum foil, approximately 40 cm x 15 cm, Congo Red dye (Toxic) Ethanol (Highly flammable, Harmful) Sulfuric acid approximately 2 mol dm-3 (Corrosive), 1 dm3, Sodium hydroxide, approximately 1.5 mol dm-3 (Corrosive), 250 cm3. Propanone (acetone) (Highly flammable, Irritant) Technical notes Congo Red dye (Toxic). Refer to CLEAPSS Hazcard 32. Ethanol (Highly flammable, Harmful). Refer to CLEAPSS Hazcard 40 (2007: 40A) Sulfuric acid approximately 2 mol dm-3 (Corrosive). Refer to CLEAPSS Hazcard 98 (2007: 98A Sodium hydroxide, approximately 1.5 mol dm-3 (Corrosive). Refer to CLEAPSS Hazcard 91.Propanone (acetone) (Highly flammable, Irritant). 1 Reasonably thick aluminium foil should be used, but, if unavailable, ordinary kitchen foil works quite well. 2 Propanone is needed to degrease the aluminium foil and it is worth keeping a bottle specifically for this purpose. The used propanone can be poured back into the bottle and kept for future use. This reduces waste disposal requirements. 3 The solid Congo Red dye needs to be made up into solution. Use 0.5 g of dye, 50 cm3 of ethanol and 50 cm3 of water and warm to dissolve. Dylon cold fabric dye (Camilla A 16) also gives good results. Red fountain-pen ink can be used as an alternative but does not give such good results. 4 Instead of a power pack, a battery or series of batteries could be used. Procedure HEALTH SAFETY: Eye protection must be worn. Before the demonstration a) Cut two pieces of aluminum foil, one 10 cm x 3 cm (the anode), the other about 30-35 cm x 12 cm (the cathode). Ensure that when the foil is folded into a cylinder it fits inside the beaker as shown below. Anodising aluminium b) Work in a fume cupboard and ensure that there are no flames close by. Work on a clean surface. Degrease the two pieces of foil by rubbing well with a paper tissue soaked in propanone and then dip the strips into a beaker of propanone for a few seconds. c) Remove the strips of aluminum from the propanone and allow drying. From this point on, only hold the aluminum foils at the top edges. d) Arrange the larger piece of aluminum into a cylinder. Fix it in position with plastic paper clips and then place inside the large beaker as shown in the diagram. e) Set up the strip of wood on the beaker and use Bluetak to attach two crocodile clips, one at the edge and one in the centre. Attach the outer clip to the aluminum cylinder. This is the cathode. f) Pour some of the cold sodium hydroxide solution (Corrosive) into a 250 cm3 beaker. Hold the smaller piece of aluminum foil with a wooden test-tube holder, and dip it into the sodium hydroxide solution. After a short while, hydrogen gas will be given off rapidly. Remove the strip after a few seconds of fizzing, and wash it in a stream of cold running water. g) Attach the aluminum strip to the central crocodile clip ensuring that it is arranged vertically (see diagram). This central strip (the anode) must not touch the aluminum cylinder. h) Carefully fill the beaker with the sulfuric acid from a measuring cylinder up to a level about 1 cm below the top of the aluminum cylinder. SAFETY: Remember that hydrogen (Highly flammable) will be evolved during the electrolysis. Keep all naked flames well away from the experiment (e.g. when heating the dye solution). Demonstration a) Connect up the circuit and use a voltage of 5-10 volt. Electrolysis is occurring when bubbling can be seen at the cathode (hydrogen). Pass a current for about 20 minutes, or longer, if time permits. b) While the electrolysis is running, heat the dye solution in a beaker to about 70 °C. An electric hotplate is preferable to a Bunsen burner. An additional beaker of boiling water will also be needed. c) Remove the central aluminum strip (the anode) and place it in the hot dye solution. Stir and leave for about 10-15 minutes. d) Transfer the aluminum anode to a beaker of boiling water and leave for another 10 minutes. This seals the dye onto the anodized surface of the aluminum and makes the aluminum oxide layer less porous. e) The upper non-anodized portion of the strip should be the original metallic grey colour whilst the rest should be coloured red. The aluminum strip can be dried in paper tissue and passed round the class. It should not be possible to rub off the dye off the surface. Teaching notes The demonstration itself The instructions may seem very detailed, but experience shows that success depends on getting the conditions just right. You should try out the experiment before carrying it out as a demonstration. It would be useful to have some sample strips of anodized aluminium to pass round. The voltage will drop during the experiment, since the anode is becoming increasingly coated with aluminium oxide. If a rheostat and voltmeter are used, the readings can be constantly monitored and adjustments made to keep the voltage approximately constant. A longer immersion in the dye will produce a strip with a deeper red colour. Leaving the strip in the dye overnight produces the best results. If time is short, omit the dye-sealing stage in boiling water. If there is time, a piece of the cathode could also be immersed in the dye. It will be found that the dye is not taken up by the metal in the same way. This is a good experiment to show students towards the end of their study of electrolysis. Chemistry points When a piece of aluminum is exposed to the air, it rapidly becomes coated with a protective surface layer of aluminum oxide. Heating the aluminum in air can make the oxide layer thicker, but anodising is much more effective. The oxide layer can be made to absorb dyes. This is useful in a range of everyday goods, such as kettles, window frames and some sports equipment, all of which need to be able to withstand extreme physical conditions. Untreated aluminium has an oxide layer about 10-8 m thick. This explains aluminiums apparent lack of reactivity in the laboratory. Anodising thickens this layer to about 10-5 m and dramatically improves the metals corrosion resistance. Oxygen is often evolved at the anode during the electrolysis of aqueous solutions. Aluminium is a reactive metal. The oxygen formed reacts immediately with the aluminium. It forms a solid oxide coating on the surface of the metal electrode. Theory for more able students For students working at a higher ability level, some or all of the following equations and explanations could be introduced: The cleaning process with NaOH: (1) Al2O3(s) + 2NaOH(aq) + 3H2O(l) à ¢Ã¢â‚¬ ’ 2NaAl
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