Tuesday, December 31, 2019
Boris Yeltsin Russian Federations First President
Boris Yeltsin (February 1, 1931 ââ¬â April 23, 2007) was a Soviet Union politician who became the first president of the Russian Federation at the end of the Cold War. Yeltsin served two terms (July 1991 ââ¬â December 1999) which were plagued by corruption, instability, and economic collapse, ultimately leading to his resignation. He was succeeded in office by Vladimir Putin. Boris Yeltsin Fast Facts Full Name: Boris Nikolayevich YeltsinKnown For: First President of the Russian FederationBorn: February 1, 1931, in Butka, RussiaDied: April 23, 2007, in Moscow, RussiaEducation: Ural State Technical University in Sverdlovsk, RussiaKey Accomplishments: Yeltsin won the first presidential election of the Russian Federation after the fall of the Soviet Union and the resignation of Gorbachev.Spouses Name: Naina Yeltsina (m. 1956)Childrens Names: Yelena and Tatyana Early and Personal Life Yeltsin was born in the Russian village of Butka in 1931. Only nine years after the establishment of the Soviet Union, Russia was undergoing a full transition to communism. Many members of Yeltsinââ¬â¢s family, including his father and grandfather, were imprisoned in gulags for being kulaks: wealthy peasants who hindered communism. Later in his life, Yeltsin attended Ural State Technical University in Sverdlovsk, one of the best technical universities in the Soviet Union, where he studied construction. For much of his time at school, he remained uninvolved in politics. After graduating in 1955, Yeltsins degree enabled him to enter the workforce as a project foreman at Lower Iset Construction Directorate, also in Sverdlovsk. However, he refused the position and opted to start as a trainee with lower pay. He believed that starting at an entry level position and working his way up to leadership would earn him more respect. This method proved to be successful, and Yeltsin was quickly and consistently promoted. By 1962, he was chief of the directorate. Just a few years later, he began working for Sverdlovsk House-Building Combine and became its director in 1965. Political Career In 1960, the law that prohibited relatives of political prisoners to join the CPSU, Russias communist party, was reversed. Yeltsin joined the CPSUs ranks that year. Though he stated on many occasions that he joined because he believed in the ideals of communism, he was also required to be a member of the party in order to be promoted to director of the Sverdlovsk House-Building Combine. As with his career, Yeltsin rose rapidly through the ranks of the Communist Party and ultimately became first secretary of the Sverdlovsk Oblast, a major region in the Soviet Union, in 1976. His political career brought him to Russiaââ¬â¢s capital city of Moscow after Mikhail Gorbachev became general secretary of the Soviet Union in 1985. Yeltsin became the head of the Central Committee of the CPSUââ¬â¢s construction and engineering department, then, a few months later, became the Central Committee secretary of construction and engineering. Finally, in December 1985, he was promoted yet again, becoming head of the Moscow branch of the communist party. This position also allowed him to become a member of the Politburo, the policy-making branch of the Communist Party. On September 10th, 1987, Boris Yeltsin became the first-ever Politburo member to resign. That October during a meeting of the Central Committee, Yeltsin laid out six points from his resignation that no one had previously addressed, emphasizing the ways in which Gorbachev and previous general secretaries had failed. Yeltsin believed that the government was reforming too slowly as the economy had still not turned around, and was, in fact, getting worse in many regions. After leaving the Politburo, he was elected to the Congress Peopleââ¬â¢s Deputy representing Moscow, then to the Supreme Soviet of the Soviet Union, which were institutions within the government of the Soviet Union, not the Communist Party. After the fall of the Soviet Union and the resignation of Gorbachev, Yeltsin was elected as the first president of the Russian Federation on June 12, 1991. First Term In his first term, Yeltsin began to shift the Russian Federation to a market economy, defying the economic and social system that defined the Soviet Union during the decades prior. He lifted price controls and embraced capitalism. However, prices rose substantially and brought the new nation into an even deeper depression. Later in his term, Yeltsin worked toward nuclear disarmament by signing the START II treaty with George H. W. Bush on January 3, 1993. The treaty stated that the Russian Federation would cut two-thirds of its nuclear weaponry. This treaty increased his unpopularity, with many Russians opposed to what appeared to be a concession of power. In September 1993, Yeltsin decided to dissolve the existing parliament and give himself broader powers. This move was met with riots in early October, which Yeltsin quelled with an increased military presence. In December after the riots were quelled, the parliament approved a new constitution with greater powers for the president as well as laws which allowed freedom to own private property. A year later in December 1994, Yeltsin sent groups into the town of Chechnya which had recently declared its independence from the Russian Federation. This invasion changed his portrayal in the West from a democratic savior to an imperialist. For Yeltsin, 1995 was plagued with health issues, as he suffered heart attacks and other cardiovascular trouble. News stories about his alleged alcohol-dependency had been running for several years. Even with these issues and his declining popularity, Yeltsin declared his intention to run for a second term. On July 3, 1996, he won his second presidential election. Second Term and Resignation The first years of Yeltsins second term were once again plagued with health issues as he faced multiple-bypass heart surgery, double pneumonia, and unstable blood pressure. The lower house of parliament brought impeachment proceedings against him for the conflict in Chechnya, an opposition which was largely led by the still-present communist party. On December 31, 1999, Boris Yeltsin resigned on Russian television, stating, ââ¬Å"Russia must enter the new millennium with new politicians, new faces, new intelligent, strong and energetic people. As for those of us who have been in power for many years, we must go.â⬠He ended his resignation speech with the statement, ââ¬Å"You deserve happiness and peace.â⬠Death and Legacy After his resignation, Yeltsin stayed uninvolved in politics and continued to suffer heart-related health problems. He died of heart failure on April 23, 2007. Yeltsinââ¬â¢s downfalls greatly define his legacy as the first president of the Russian Federation. He is remembered for a presidency rife with economic troubles, corruption, and instability. Yeltsin was favored as a politician, but largely disliked as president. Sources Colton, Timothy J.à Yeltsin: a Life. Basic Books, 2011.Minaev, Boris, and Svetlana Payne.à Boris Yeltsin: the Decade That Shook the World. Glagoslav Publications, 2015.ââ¬Å"Timeline: Former Russian President Boris Yeltsin.â⬠à NPR, NPR, 23 Apr. 2007, www.npr.org/templates/story/story.php?storyId9774006.In-text CitationComments
Monday, December 23, 2019
Internet Advertising Essay - 867 Words
Internet Advertising Internet Advertising is the way of the future and it is very evident since many companies and businesses have their own web sites and advertisements are located all over the World Wide Web. The Internet or World Wide Web is quickly becoming the most effective way for a business to advertise their products or services to customers. Web sites such as search engines or small sites that sell advertisement space for sponsoring are profiting highly from the increase of advertising on the Internet. Also contributing to the profit of businesses is the fact that the number of people that have access to the internet is growing as well as internet services which will allow potential customers to view these advertisements.â⬠¦show more contentâ⬠¦Internet advertising is less expensive compared to direct advertising which creates more profit for advertisers and businesses. When compared with advertising in magazines or on television, Internet advertising is far more beneficial and less expensive. Smaller businesses should take into consideration, the Internet advertising campaign because it is less expensive, more interactive, and easier to track and target than other advertising methods. Studies have also shown that awareness of participating brands increased 5%, on average. In addition, 49% of the study participants said they recalled seeing a tested advertising banner on a particular site. Current click-through rates average about 20% better than other direct-marketing methods (click-through: the action of following a hyper link within an advertisement). Another advantage of internet advertising over direct or local advertising is the fact that it is global and the advertiser is allowed to advertise to the whole world making the advertising more effective and beneficial. Banners advertising the business or its goods and services would be placed on a certain site and when an interested consumer clicks on the graphic, he/she is usually redirected to the businesses site according to the particular goods and services being offered. Internet advertising is also more interactive compared to magazine or television advertisements because theShow MoreRelatedAdvertising On The Internet : Internet1985 Words à |à 8 PagesGiacomo Randazzo Ms. Blair English III 26 March 2015 Advertising on the Internet Most of the websites collect money through advertisement; websites collect a bunch of information about who visits the page that they use to target their advertisements to services and product that reflect his interests. So targeted advertising is a good thing because it allows the web to run without the necessity to pay for every visited page, but people should be informed and conscious of where the information websitesRead MoreOnline Advertising And The Internet2471 Words à |à 10 PagesThe internet has made everything simple especially in business. The world has changed to become a global village where all people can access. They do that to check on what is new in the market or the current trends. Marketers and advertisers have seen an opportunity in the fact that people are always on the internet. They market their products on the internet by posting them on different websites for people to be able to see them. That type of advertising that takes place on the internet is referr edRead MoreInternet Advertising Essay1723 Words à |à 7 PagesAdvertising can mean many different things in todayââ¬â¢s world. When advertising first was developed it was done by would of mouth and the classic flyer or poster. Then it moved up to using the radio to help capture a bigger audience. After that it moved towards the television where an even bigger audience could be reached. Lastly companies started to realize the shear amount of traffic that was generated by the Internet. The Internet first started to get popular in the mid 1990ââ¬â¢s. Where only peopleRead MoreTelevision And The Internet Advertising1427 Words à |à 6 PagesTelevision and the internet ads on use of marijuana Rhetorical Analysis Television and the internet is a good channel of passing the messages about the adverse effects of the use of marijuana. The office of the National Drug Control Policy is an American government action which depends on safeguards the health of the people of America. The above the influence initiative is a program of the not-for-profit Partnership at Drugfree.org. Their overall goal is to help teens reject negative influencesRead MoreInternet Advertising : Google Adwords1954 Words à |à 8 PagesInternet Advertising: Google Adwords Josh Moelis Pace University jm11041n@pace.edu Introduction Internet advertising has been around for just about as long as the internet has. There are also many different forms of internet advertising such as banner ads, social media ads, email ads, Pay-Per-Click (PPC), Cost-Per-Mile (CPM), affiliate marketing and many many more. I am going to be focusing on pay-per-click advertising, specifically Google Adwords. Google Adwords is a marketing tool by GoogleRead MoreEssay about Internet Advertising1719 Words à |à 7 PagesInternet Advertising The November cover story for Newsweek was entitled ââ¬Å"e-lifeâ⬠and the issue was dedicated to the many ways that the Internet is changing our lives and work. While the changes have affected many industries and many jobs, one of the biggest changes in marketing and sales is the rapid and unpredictable growth of Internet-based sales and advertising. Currently, many users benefit from the use of ââ¬Å"freeâ⬠email sites and Web-search portals, all of which are funded by revenues fromRead MoreAdvertisements And The Internet Of American Advertising1146 Words à |à 5 PagesAdvertisements and The Internet ââ¬Å"Burn it up and Flush it out !â⬠The prominent Kim Kardashian commercial regarding the weight loss supplement, QuickTrim aired on television years ago, in order to display that it is easy to have oneââ¬â¢s dream body in a blink of an eye through one commercial. This method of twisting the truth is then applied when a person logs onto Twitter a few hours later and sees pictures of the Kardashian sisters posing and showing off their bodies, the ones that they achieved simplyRead MoreInternet Marketing Relevance and Consumer Attitudes toward Internet Advertising1245 Words à |à 5 Pagesdiscusses internet marketing relevance and investigates antecedents of consumer attitudes toward Internet Advertisement. The analysis is based on a consumer survey conducted in India as well as other countries. For this purpose, a representative quota sample of Internet users in India has been interviewed. The finding of this study provides marketers with an understanding of consumers, th eir attitude toward advertising, so designers and marketers can better strategize their advertising designs. InternetRead MoreEssay on The Legality and Ethics of Internet Advertising1777 Words à |à 8 PagesThe Legality and Ethics of Internet Advertising ABSTRACT: Recently, DoubleClick.com, one of the worldââ¬â¢s premier Internet advertising firms was at the center of a Federal Trade Commission investigation on privacy. Consumer privacy advocates have charged the company with infringing on the privacy of websurfers because of the aggressive means it uses to gather data for profit. This paper discusses the legal and moral issues surrounding these tactics. Were the companyââ¬â¢s aggressive tacticsRead MoreAdvantages and Disadvantages of Internet Advertising In Promoting Products to Consumers671 Words à |à 3 Pagescomputers and internet that is being used by people of all ages, there is an increase in number of the World Wide Web users worldwide. Internet plays a very significant role in everyoneââ¬â¢s life most especially to business minded people. Business companies need to promote their products. In order for those companies endorse and sell products, they need to have a good marketing strategy. This is the time whe rein they need to advertise it. Advertising comes in many ways. However internet advertising is one
Saturday, December 14, 2019
Continental Airlines Free Essays
Meagan Young Chapter 10 I believe that Lorenzoââ¬â¢s confrontation with Continentalââ¬â¢s unions could have been conducted a different way. They could simply listen to each otherââ¬â¢s viewpoint and not interrupt with one another is speaking. This way each other can hear their viewpoint and maybe understand one another better. We will write a custom essay sample on Continental Airlines or any similar topic only for you Order Now If Lorenzo would have listened to what his employees were trying to say, he may have gotten ideas from them and used them for his company. Both these companies experienced commonalities and contrasts. Both Bethunes and Southwest Airlines experienced debt issues. Both companies were puzzled as how to deal with this situation. Both companies however had the similar approaches as how to deal with the debt situations. Bethune definitely has a better management style than Lorenzoââ¬â¢s. this is because Bethune was willing to come up with solutions to come out of debt. He also made dramatic changes. In 1995, through a ââ¬Å"renewed focus on flight schedules and incentive pay,â⬠he greatly improved on-time performance, along with lost-baggage claims and customer complaints. Better communications was also a key element in improving employee relationships and the spirit of teamwork. Information was shared with employees through newsletters, updates on bulletin boards, email, voice-mail, and electronic signs over worldwide places. As you can see Bethune really wanted to improve Continental Airlines because he wanted what was best for the company. Bethune proved a master at changing employeesââ¬â¢ attitudes and their sense of pride. Few top executives ever faced such a negative workforce, reflecting the Lorenzo years. But Bethune changed all this, and in such a short time. is open-door policy and open houses to encourage employees to interact with him and other top executives was a simple gesture, but so effective, as was his opening wide the channels of communication about company plans. The incentive plans for improving performance, and the freeing up of employee initiatives by abolishing the rigidity of formal policies, were further positives. He enge ndered an atmosphere of teamwork and a personal image of an appreciative CEO. This goes to show that Bethune is a trustworthy man and cares much about his company and the employees. The paint issue shouldnââ¬â¢t be a big issue. It gave the company a new look I think. Giving employees some kind of reward such as a bonus or incentive seems ideal. When they reach a certain goal or percentage and show they are hardworking employees, they could receive one of these. Before doing this I would supervise how they are working to make sure they are doing what they are supposed to. After studying their work ethics I would then determine what kind of reward I would present to them. Lack of communication is one of the biggest issues with not only top executives but anyone in the company. Iââ¬â¢m sure not all of the upper management had the same ideas for Continental, and because of this some were left behind. This could be a downfall because one of them could have had a really good idea to present to the company. Because workers are not getting paid what they should, you can offer them something else. You can offer them better company benefits. This can help the employee tremendously, especially if they have a family. You could also tell the workers that if they reach a certain percentage that they can receive a raise. All of these ideas can motivate an employee to work harder at their job. How to cite Continental Airlines, Papers
Friday, December 6, 2019
Intergranular Stress Corrosion Cracking â⬠Free Samples to Students
Question: Discuss about the Intergranular Stress Corrosion Cracking. Answer: Introduction Corrosion can be defined as a natural process with the help of which refined metal is converted into more chemically- stable form such as its sulfide, hydroxide or oxide (Talbot Talbot, 2018). It is the slow destruction of materials which are usually metals by electrochemical and / or chemical reaction within their environment. Materials other than metals such as polymers or ceramics also suffer from corrosion, however, the term degradation is more commonly used in this context. The valuable properties of materials and structures are degraded as a result of corrosion including the appearance, strength and permeability to gases and liquids. Passivation is beneficial in the mitigation of corrosion damage. The hindrance of passivating film forming capability can even lead to the corrosion of high- quality alloy. Right grade of material is required to be selected for the particular environment in order to ensure the long- lasting performance of such group of materials. If the passive fi lm suffers from a breakdown as a result of mechanical or chemical factors, the resultant modes of corrosion may include crevice corrosion, pitting corrosion and stress corrosion cracking. The focus of this report is on ammonia stress corrosion cracking. Stress corrosion cracking (SCC) can be demarcated as the growth of crack formation in a corrosive environment (Cunningham, Bottleberghe Greene, 2017). The protective oxide layer is sometimes destabilized by the corrosive environment under definite conditions without causing general corrosion. The reformation of oxide is prevented after a crack due to destabilization. Ductile metals that are subject to a tensile stress have chances of facing an unexpected sudden failure specifically at elevated temperature. Stress corrosion cracking is caused by the chemical environment which is only a little corrosive to metal (Cheng, 2013). Brightness is noticed in metals with faces severe stress corrosion cracking while they are filled with cracks that are microscopic. This is the most common factor as a result of which the stress corrosion cracking goes undetected before its failure. Stresses can also be the outcome of crevice loads because of stress concentration or can be instigated by residual stresses or type of assembly. Ammonia stress corrosive cracking is a form of SCC that takes place in brass tubes in cooling water service which has been contaminated by ammonia as a result of biological growths or any other contamination. The occurrence of this cracking can also be the consequence of intentional addition of ammonia as a neutralizer to the process streams by someone who is not aware its impact on the brass tubes. Brittle fracture is experienced on bending by the brass condenser tubes on the presence of significant ammonia stress corrosion cracking (Raja Shoji, 2011). Carbon steel equipment are also affected by the ammonia stress corrosion cracking but unlike the mechanism of cracking on brass which takes place in an aqueous solution, steal equipment cracking takes place in an anhydrous ammonia. In other words, the presence of liquid ammonia in oxygen can result in stress corrosion cracking in carbon steels (Shi, et. al., 2015). With the increase in the yield strength of the plate material, local hardness of the welds and increased strength of welds, the probable problem of stress corrosion cracking is also increased. Vulnerability to this issue is also faced by the systems that are contaminated with oxygen/ air. However, cupro- nickel alloys are not found to be vulnerable to ammonia stress corrosion cracking (McDougal Stevenson, 2005). During the normal operations, the applied stress levels are not high as required to initiate cracking.The usage of eddy current such as eddy current array or pulsed eddy current testing is considered to be one of the best techniques for the purpose of inspection of ammonia stress corrosion cracking in brass tubes. With specific reference to 18Cr-8Ni steels, the characteristics of stress corrosion cracking provides that susceptibility is found in alloy to transgranular stress corrosion cracking at the time when there is possibility of a passive/ active transition or when a noble surface is produced by the responses in alloy surface which may be metal or oxide, co- planar arrays of dislocations are exhibited by the alloy or high work- hardening rate is exhibited by the alloy, specific electrochemical reactions are there (which are considered to be the chlorides frequent penetration of passive films) (Kim, Kwon, Kim, Hwang Kim, 2011). Mechanism of Ammonia Stress Corrosion Cracking The proposal of various mechanisms has been made for the purpose of explaining the synergistic stress corrosion interactions the occurrence of which is found at the crack tip. Stress corrosion cracking is expected to be caused as a result of more than on process. The mechanisms have been classified into two main categories namely cathodic mechanisms and anodic mechanisms. The occurrence of both cathodic and anodic reactions is a must during corrosion. This means that the phenomenon resulting in crack propagation may be linked with either form (Parkins, 2011). In alloys, the mechanism of anodic dissolution related to stress corrosion cracking is due to the reason of heterogeneity in precipitates distribution with diverse electrochemical anodicity associated with alloy matrix. Then there is a rapid dissolution of the anodic precipitates which further results in the extension of intergranular crack until there is the occurrence of re-passivation (Newman, 2002). Simple active dissolution and elimination of material from the crack tip is the most common anodic mechanism (Javidi Horeh, 2014). On the other hand, the most common cathodic mechanism is absorption, hydrogen evolution, embrittlement and diffusion. The Crack- Propagation Mechanisms assumes that the occurrence of the breakage in interatomic bonds of crack tip is the result of either mechanical fracture (brittle or ductile) or chemical solvation and dissolution. Normal fracture processes are included in the mechanical fracture that is expected to be induced or stimulated by any of the following interactions between environment and material. Surface reactions Surface films Absorption of ecological species Responses in metal ahead of crack tip All the mechanical fractures that have been proposed are found to contain some of these processes as an important step in the process of stress corrosion cracking. Surface absorption mechanism suggests that the absorption of active surface components on the hard surface can subsequently result in reducing the deformation resistance and strength of solids. In this mechanism, the interatomic bonds are weakened by the absorbed species at the crack tips thereby resulting in either the promotion of growth in cracks by decohesion or the facilitation of emission of dislocations and nucleation. The enhance dislocation emission further leads to the promotion of joining of the crack tip. Consequently, intergranular fracture or brittle cleavages are produced. This is similar to hydrogen embrittlement but limited to a surface one such that effect can be produced by elements other than hydrogen (Marcus, 2011). It is believed that two diverse mechanisms cause the occurrence of stress corrosion cracking. These are the hydrogen embrittlement and active path corrosion. It is found that the cracking in active path corrosion form is caused by local corrosion of crack tip. It further proceeds on its electrochemically active way with respect to surrounding metal. Cracking in hydrogen embrittlement mechanism is found to be caused by entrance of hydrogen into metal which in turn results in reducing the deform ability (Chene, 2016). Due to the non- consideration of hydrogen embrittlement as a corrosion process, therefore, the cracking that results due to this mechanism is often excluded from the stress corrosion cracking (Eliaz, Shachar, Tal Eliezer, 2002). Affected Materials and Equipment Stress corrosion cracking is suffered by certain aluminium alloys and austenitic steels in the existence of chlorides, copper alloys and nitrates in the presence of ammoniacal solutions and mid steel in the existence of alkali (Brandl, Malke, Beck, Wanner Hack, 2009). Therefore, the usefulness of austenitic stainless steel is limited to containing water with more than little ppm content of chlorides at temperature that is greater than 50C (Li, Chu, Wang Qiao, 2003). Structural steels that are highly tensile are supposed to crack in an unexpectedly brittle way in the entire variety of aqueous environments, specifically in the presence of chlorides. The subcritical crack growth is demonstrated i.e. the propagation of small surface flaws under fracture mechanics predicts that there should be no occurrence of failure. Environmental stress cracking which is a similar process is found to occur in polymers when exposure is faced by the products to aggressive chemicals or specific solvents such as alkalis and acids. Similar to the case of metals, the attack is limited to the particular chemicals and polymers. Sensitivity is faced by the polymers to environmental stress cracking where there is no compulsory chemical degradation of materials by the attacking agents. Sensitivity to degradation by acids is faced by Nylon which is considered to be a process termed as hydrolysis. When strong acids attack nylon mouldings, it results in severe cracking. Elastomers also suffer from the formation of cracks by ozone attack which is a different form of stress corrosion cracking in polymers. Double bond are attacked in the rubber chain with styrene- butadiene rubber, natural rubber and nitrate butadiene rubber due to the small quantity of gas in air as they are considered to be most sensitive to degradation. Critical strain is found to be very little when ozone cracks are formed in products under stress. The orientation of cracks is at the correct angle to strain axis so that its formation will take place around the boundary of rubber tube. The occurrence of such cracks in fuel pipes have proved to be very dangerous due to the growth in cracks from the surfaces that are exposed from outside into the bore of the pipe. This has the chances of resulting in fire and fuel leakage. The prevention of ozone cracking can take place by the addition of anti- ozonants to the rubber prior to vulcanization. Automobile tire sidewalls often suffered fro m ozone cracks but now such problem have been reduced as a result of increasing use of additives. However, the recurrence of problem is seen in the equipment such as unprotected products like seals and rubber tubing. Ceramics do not suffer a lot from this effect as they are more resistant to chemical attacks. However, phase changes are commonly noticed in ceramics under stress which subsequently results in hardening instead of failure. The toughening mechanism has the capability of enhancing the oxidation of decreased cerium oxide which further results in slow growth of the crack and impulsive failure of dense ceramic bodies. The effect of Stress corrosion cracking on a material typically falls between fatigue and dry cracking threshold of that particular material. The requisite tensile stresses may be in directly applied stresses form or in residual stresses form. Carbon steel equipment are also affected by the ammonia stress corrosion cracking but unlike the mechanism of cracking on brass which takes place in an aqueous solution, steal equipment cracking takes place in an anhydrous ammonia. Appearance/ Morphology/ Damage The consequence of stress corrosion is the appearance of corrosion cracks on the metal surface. Moreover, intergranular cracking in stress corrosion cracking advances without apparent preference for boundaries (King, Johnson, Engelberg, Ludwig Marrow, 2008). The occurrence of both types of cracking depends on metal structure or the environmental structure and is in the same alloy. Stress corrosion cracks are initiated at surface flaws which then grow into small macroscopic evidence of mechanical deformation in alloys and metals that are usually considered to be ductile. Pits formation are found in electrochemical terms when potentials exceeds the pitting capability. The same parameters are considered as the basis of evolution between pitting and cracking that control the stress corrosion cracking (Lu, Chen, Luo, Patchett Xu, 2005). The change in the potential and corrosive environment within a pit may be essential for enabling the pit to perform the function of a crack initiator. There are a variety of examples in which the initiation of stress corrosion cracks is noticed at the base of a pit due to intergranular corrosion. The intergranular stress corrosion cracking also leads to crack propagation in these cases (Arioka, Yamada, Terachi Staehle, 2006). It is expected that the development of same local electrochemistry is not common in the preexisting pit like in the case of one grown during service. The initiation of stress corrosion cracks are also noticed in the absenteeism of pitting by slip- dissolution or intergranular processes (Arafin Szpunar, 2009). For this, the requirement arises for differences in bulk chemistry and grain- boundary chemistry (Knight, Birbilis, Muddle, Trueman Lynch, 2010). Such conditions are mostly experienced by sensitized austenitic stainless steels or with impurities segregation such as sulfur, phosphorus or silicon in various materials (Meng, Zhang, Zhuang Zhang, 2016). The propagations subcritical nature may be credited to the release of chemical energy as the crack propagates. This can be presented in the following equation form: Release of elastic energy + chemical energy = deformation energy + surface energy The damage is caused at a slow rate as SCC is a delayed failure process. The appearance of SCC is observed in environment/ alloy combinations resulting in the creation of a film on the surface of metal. These films may be in the form of tarnish films, passivating layers or dealloyed layers. The rate of uniform or general corrosion is subsequently reduced due to these films which in turn make the alloy necessary for battling against uniform corrosion in the environment. Prevention/ Mitigation The combination of three factors results in stress corrosion cracking namely exposure to a corrosive environment, a susceptible material and tensile stresses above edge. The initiation of stress corrosion cracking becomes impossible if any of such factors are eliminated. However, a variety of approaches can be utilized for the purpose of preventing or delaying the onset of SCC. Firstly, the control strategy needs to be selected for stress corrosion cracking that will initiate its operations at the design stage. It will further focus on the material selection, stress limitation and control of the environment. The development of new alloys that are more resistant to stress corrosion cracking can be chosen as a conventional approach for the purpose of controlling the problem. However, this proposition is costly and requires enormous time investment for achieving only marginal success (Nugent Khan, 2014). For the purpose of controlling stress corrosion cracking, awareness needs to be created regarding the possibility of its occurrence at the design and construction stages. The problems related to stress corrosion cracking can be avoided if due attention is paid at the time of making selection of materials. Those materials should be chosen that are not susceptible to stress corrosion cracking in the service environment and their correct processing and fabricating should be ensured (Je Kimura, 2014). High temperature water is the example of environments that are aggressive and result in causing stress corrosion cracking of most materials. High yield strength and other mechanical requirements can create difficulty in reconciling with SCC resistance. The existence of stress in the components causes stress corrosion cracking. Therefore, in order to control SCC, the method adopted should consist of eliminating or reducing that stress below the starting point of SCC (Seong, Frankel Sridhar, 2015). Controlling the environment is considered as the straightest way of controlling stress corrosion cracking by removing or replacing that particular component of environment that is liable for the difficulty. When the cracking is the result of species that are the necessary components of the environments then the options related to environment control consists of addition of inhibitors, modification of the electrode capability of the metal or creating isolation for the metal from the environment with the help of coatings. There are several ways with the help of which ammonia stress corrosion can be prevented in steel equipment. Greater susceptibility is faced by the systems that have not undergone postweld heat treatment (PWHT). Therefore, there is a requirement for proper PHWT in order to prevent ammonia stress corrosion cracking. The cracking of wheel can be easily obstructed with the help of adding a little quantity of water i.e. nearly 0.2% to the anhydrous ammonia. Conclusion Therefore, it can be concluded that ammonia stress corrosion cracking is the form of corrosion that takes place in brass tubes in cooling water service which has been contaminated by ammonia as a result of biological growths or any other contamination. The proposal of various mechanisms has been made for stress corrosion cracking such as cathodic and anodic mechanisms and crack propagation mechanism. Various materials and equipment suffer from stress corrosion cracking such as aluminium alloys, austenitic steels, polymers, elastomers, ceramics and carbon steel equipment, etc. The ammonia stress corrosion appears in the form of corrosion cracks on the surface of metal. Stress corrosion cracks are initiated at surface flaws which then grow into small macroscopic evidence of mechanical deformation in alloys and metals that are usually considered to be ductile. Furthermore, various steps can be undertaken for the purpose of prevention or mitigation of ammonia stress corrosion cracking. T his includes the elimination of the factors such as corrosive environment, a susceptible material and tensile stresses above edge. Moreover, awareness needs to be created for the purpose of selection and controlling of materials along with controlling the stress and environment. References Arafin, M. A., Szpunar, J. A. (2009). A new understanding of intergranular stress corrosion cracking resistance of pipeline steel through grain boundary character and crystallographic texture studies.Corrosion Science,51(1), 119-128. Arioka, K., Yamada, T., Terachi, T., Staehle, R. W. (2006). Intergranular stress corrosion cracking behavior of austenitic stainless steels in hydrogenated high-temperature water.Corrosion,62(1), 74-83. Brandl, E., Malke, R., Beck, T., Wanner, A., Hack, T. (2009). Stress corrosion cracking and selective corrosion of copper?zinc alloys for the drinking water installation.Materials and corrosion,60(4), 251-258. Chene, J. (2016). Stress corrosion Cracking and Hydrogen embrittlement. InStress Corrosion Cracking of Nickel Based Alloys in Water-cooled Nuclear Reactors(pp. 295-311). Cheng, Y. F. (2013). Stress Corrosion Cracking of Pipelines. John Wiley Sons. Cunningham, A., Bottleberghe, J., Greene, D. (2017). A Method for Detecting Stress Corrosion Cracking and the Influence Environmental Factors. Eliaz, N., Shachar, A., Tal, B., Eliezer, D. (2002). Characteristics of hydrogen embrittlement, stress corrosion cracking and tempered martensite embrittlement in high-strength steels.Engineering Failure Analysis,9(2), 167-184. Javidi, M., Horeh, S. B. (2014). Investigating the mechanism of stress corrosion cracking in near-neutral and high pH environments for API 5L X52 steel.Corrosion Science,80, 213-220. Je, H., Kimura, A. (2014). 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