How to watch your brother die free essay sample

Michael Lassell portrays himself as a straight man in his poem â€Å"How to Watch your Brother Die.† In reality he is a 21st century gay poet. The poem tells the story of a man, this being the straight narrator, who is called across the country to visit his brother as he lies on his deathbed. Later in the poem we learn the dying brother is suffering from HIV, and had been disowned by his brother because of his homosexuality. As the poem goes on, the narrator creates a unique and close relationship with his brother’s lover. Through the trials of the writer, the poem conveys the struggles and judgment received by the gay community, ultimately creating a life-changing shift in his morals. The reader can see and understand the changes in the narrator because of Lassell’s use of reversed roles, second-person voice, and symbolism. â€Å"Michael Lassell often writes about life as a gay man. We will write a custom essay sample on How to watch your brother die or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page He speaks bravely about sexuality and vulnerability.† (480) In this poem Lassel had to shift his role. He had to step into a perspective of someone whose beliefs are on the other side of the spectrum. What we know about the narrator before he wrote the poem is that he lived a conservative life. We know this because he is married to a woman who has no interest in her husband’s dying brother, simply because he is gay. The lover tells him, â€Å"Forgive yourself for not wanting to know him.† (482) This tells us the narrator disagreed with his brother’s sexual orientation enough to take a step out of his life, and discontinue their relationship. By portraying the story from the view of an orthodox straight man, Lassell creates a stronger connection and understanding with his non-gay readers, while still portraying a new perspective. Lassell tells you the story as if it is an experience you are going to soon face and teaches you how to react appropriately, walking you through each step. He used second person to allow the reader to connect with the story on an emotional level. In the first line of the poem he says, â€Å"When the call comes, be calm. Say to your wife, ‘My brother is dying I have to fly to California.’† (480) After reading the first two sentences the reader can immediately understand the heart-ships the narrator will soon face. Everyone carries a little bit of judgment but that judgment seems to drop when it’s something involving yourself or the ones you love most. Except for the dying brother, the  narrator and the lover, there are no other big roles in this poem. Even so, it doesn’t mean the other characters didn’t work together to play a key part in the poem. They symbolize the hate he had before he came, and the judgment people hold against ideas they don’t understand. The first character we are introduced to is the doctor, described as â€Å"remote† and is said to â€Å"talk with a steel face on.† In most cases doctors show sympathy toward their patients and the patient’s loved ones, but in this instance he didn’t care. He distanced himself off from the family, and the sorrow they felt because of his opposed opinion to homosexuality. The narrator and the lover take a trip to Mexico in search of illegal drugs in hopes to help the dying brother live longer. When the border guard learns what the drugs are for and sees the two men link arms he refuses to let them to bring the drugs through the border. When the narrator contests to this he can â€Å"See in the guard’s eye how much a man can hate another man.† (481) When the narrator makes a call home to his wife he starts to question their love because the love his brother shared with his partner was so visibly strong, she brushes this off, not wanting to know the details. The last is the funeral director who refused to â€Å"embalm the body in fear of contamination† (482). The funeral director symbolizes the ignorance and the lack of knowledge people gain when they choose to hate someone or something. They choose to be dumb to the idea because they cannot connect or understand it, and refuse to take a look into another man’s perspective. Before the narrator came to watch his brother die, he shared the same views as all of the characters talked about. The wife demonstrates the commitment he has to these views, and that the epiphany he had during the loss of his brother will not be an easy life shift. Although his view on homosexuality and love changed, it doesn’t mean the world, and all its people have. The narrator shifted his mindset completely by having a little taste of the gay man’s hardships. He started with the view that being gay is wrong and that it is okay to brush someone of so easily because of it, to feeling that judgment and not being able to wrap his mind around â€Å"another man’s hate†. At the face of his brother’s death he was able to come to understanding of the difficult life his brother must have led by facing a constant struggle between who he was and the society that demanded what right and wrong is. Since he had to defend himself at every corner of his existence it became clear to his brother who now feels the pain and will embrace his children upon his return home, with an additional knowledge and the sense of relief that they will not have to experience the same. . Lassell, Michael. â€Å"How to Watch your Brother Die.† Alvarado, Beth, and Barbra Cully. Writing as Revision, Fourth Edition. Boston, MA. Pearson, 2012. 480-82. Print.

Free Essays on The Crusades

The Crusades The crusades were military expeditions launched against the Muslims by the Christians in an attempt to regain the Holy Land. They took place between 1095 A.D. and 1270 A.D. It was one of the most violent periods in the history of mankind. The starting point of the crusades was on November 18, 1095 A.D. When Pope Urban II opened the Council of Clermont. On November 27, outside the French city of Clermont-Ferrand, the Pope made an important speech. He called upon everyone to help the Christians in the east to restore peace. The crowd's response was very positive. Garments were cut into the shape of a cross, which was attached to people's shoulders in an imitation of Christ (Matthew 10:38). (1) The original object of the First Crusade was to help Christian churches in the east. The new goal became to free the Holy Land from Muslim control, especially Jerusalem. Pope Urban II stayed in France until September 1096 to provide leadership and guidance for the members of the First Crusade. He urged churchmen to preach the cross in France. Urban wanted the crusading army to be mostly made up of knights and other military personnel. Since the news of his speech at Clermont spread through the west, people from all social classes and occupations joined the Crusade. As a result of Urban losing control of personnel, violence was launched against the Jews of northern France. This violence was mostly instigated by bands of the urban and rural poor led by men like Peter the Hermit and Walter Sans-Avoir. These groups lacked supplies and discipline. They attempted to reach Constantinople but most of them never got that far. The leaders in lands that they passed through were frightened and killed many of the crusading bands. Some did get to Constantinople and traveled across the Bosphorus in August 1096. There they split into two groups. One tried to overtake Nicaea and was unsuccessful. ... Free Essays on The Crusades Free Essays on The Crusades The Crusades The crusades were military expeditions launched against the Muslims by the Christians in an attempt to regain the Holy Land. They took place between 1095 A.D. and 1270 A.D. It was one of the most violent periods in the history of mankind. The starting point of the crusades was on November 18, 1095 A.D. When Pope Urban II opened the Council of Clermont. On November 27, outside the French city of Clermont-Ferrand, the Pope made an important speech. He called upon everyone to help the Christians in the east to restore peace. The crowd's response was very positive. Garments were cut into the shape of a cross, which was attached to people's shoulders in an imitation of Christ (Matthew 10:38). (1) The original object of the First Crusade was to help Christian churches in the east. The new goal became to free the Holy Land from Muslim control, especially Jerusalem. Pope Urban II stayed in France until September 1096 to provide leadership and guidance for the members of the First Crusade. He urged churchmen to preach the cross in France. Urban wanted the crusading army to be mostly made up of knights and other military personnel. Since the news of his speech at Clermont spread through the west, people from all social classes and occupations joined the Crusade. As a result of Urban losing control of personnel, violence was launched against the Jews of northern France. This violence was mostly instigated by bands of the urban and rural poor led by men like Peter the Hermit and Walter Sans-Avoir. These groups lacked supplies and discipline. They attempted to reach Constantinople but most of them never got that far. The leaders in lands that they passed through were frightened and killed many of the crusading bands. Some did get to Constantinople and traveled across the Bosphorus in August 1096. There they split into two groups. One tried to overtake Nicaea and was unsuccessful. ...

On the City of Tulsa Essay Example | Topics and Well Written Essays - 500 words

On the City of Tulsa - Essay Example Despite the economic potential further development brings in, we must recognize the ill-effects that come with it. A study on population dynamics has questioned the sustainability of our natural resources amidst the current population boom and the influx of illegal immigrants in the country not to mention the legal immigrants. The law of supply and demand may create an imbalance if the natural resource is scarce. No matter how we try to accommodate improvement but nature refuses to provide the demands due to over-population and over-usage will thereby result in a tangible scarcity of resources. Man’s basic needs for food and water can no longer be met and that is an ill-effect of too much economic improvement. The issue of illegal immigration has been placed in the background in favor of several more pressing issues. However, we cannot ignore that our country is approaching a population 280 million of which illegal immigrants are not even accounted for. If we continue and allo w the influx of illegal immigrants, food and water scarcity will be experienced in the later years to come. Compassion should start within us all and consider these illegal immigrants have a home country to return to when dire consequences would hit us, but we only have this country to return to, therefore it is our sole responsibility to make our country sustainable and viable for us all. All Americans must be educated on the effects of the current population boom. Education creates consciousness for every American to focus on his responsibility towards his country and work on acceptable jobs to help reduce the influx of â€Å"aliens†. The aim is not to discriminate anybody in particular, but to work towards the common goal of having jobs for everyone. Americans are complaining about â€Å"fewer jobs† available to them.  

Teaching ESL through Culture Essay Example | Topics and Well Written Essays - 1000 words

Teaching ESL through Culture - Essay Example The complexity was actually compounded when the aspect of culture comes into play. With the growth of technology that contributed to breaking barriers of time and distance, people from various cultures felt the most eminent need to learn ESL, considering English as the universal language. In this regard, the objective of the essay is to review six pertinent literatures that delve into the subject of teaching ESL with culture seen as playing a crucial role in learning and reinforcing literacy and proficiency. Defining Culture From evaluating the contents of the six articles, one observed that in discussing the role that culture plays in teaching ESL, several authors acknowledged that defining the term ‘culture’ proffered challenges due to its broad perspectives. Lafayette acknowledged that â€Å"because culture can be defined so broadly, it is often difficult for teachers to select those aspects that should be included in the curriculum at various levels of instructionâ €  (6). ... omprises a set of symbolic systems, including knowledge, norms, values, beliefs, language, art, customs, as well as habits and skills learned by members of a given society† (Young, Sachdev, & Seedhouse, 2009, p. 149). From among the definitions noted, Young, et al. included language as part of the definition acknowledging the important role it plays in the communication process. Problems in Incorporating Culture in Teaching ESL Aside from the dilemma in defining the term, most authors have revealed that there were apparent apprehensions for incorporating teaching culture in the ESL curriculum (Lafayette, 1978, p. 6). Sauve have enumerated seven problems with teaching culture in the Canadian ESL classroom, to wit: (1) naming â€Å"a Canadian culture† (Sauve, 1996, p. 17); (2) unprepared academic programs for teaching cultural aspects; (3) a conceptual dilemma of defining ESL; (4) perceived decline in valuing the ESL professional; (5) the role of immigrant educators as ESL staffs; (6) biased society in favor of white, Anglo-Saxon, Christian and of middle class tradition and values (Sauve, 1996, p. 22); and (7) time context and priorities. The article written by Young, et al. highlighted concerns that included ambiguity in determining â€Å"whose culture should be a focus for study on English language program† (Young, Sachdev, & Seedhouse, 2009, p. 151) and how effective an identified approach would be after taking into account the increasing predominance of nonnative speaking (NNS) teachers of a language and their acknowledged difficulty in teaching culture with the ESL realm. Finally, Byram and Kramsch (2008) disclosed the problem of cultural translation by citing Geertz’s words as: â€Å"Translation is not a simple recasting of others' ways of putting things in terms of

Selection of Web Server Software for Client Essay

Selection of Web Server Software for Client - Essay Example The client would also want a customised Content Management System to be coded so that they can easily change the content on site and add new pages, thus, making it flexible for accommodating changes. The current Information Technology Infrastructure is not very advanced and includes basic users with little knowledge of web technologies. The client is also not willing to spend a hefty amount but do requires a robust, agile and flexible system. 2) - Comparison of available technologies After going through the detailed requirements document from the client and understanding his needs, two sets of technologies can be recommended to the client. Let us compare and contrast between these two sets to see which set can be more viable for the client in the future. The two sets of technologies are: 1) - Internet Information Services, Active Server Pages and SQL Server (Microsoft Products) 2) – Apache, PHP and MySQL It is to be noted here that that both sets have a web server, a web progr amming language and a database. We should now just compare these technologies individually in detail and then in the subsequent sections, we will relate our results with the available IT infrastructure of the client. 2.1 - Web Servers The function of web server is to deliver services (web content) to the users who are requesting access via Hyper Text Transfer Protocol. The HTTP protocol is normally set by web browsers and doesn’t really require manual intervention or settings by the user. Web content here actually means all the media that is available on the web page. (WDN, 2012) The following table actually shows the differences between two available web servers: Apache and Internet Information Services. APACHE IIS Current market share at 65% Current market share at 15% Designed to work with most Operating Systems IIS designed to work only with Windows Operating Systems Co-operation is limited with the host system and there are no specific utilities available in every OS to monitor web service Greater co-operation with the host system and control through various Windows utilities Independent Request handler is limited Independent Request handler is not limited .Net languages aren’t integrated Support for most programming languages Open source software Comes with Windows OS More secure Less secure because of multiple system calls 2.2 - Web Programming Languages A web programming language or a server side scripting language is a language designed for developing web pages of dynamic nature. The following table shows the comparison between two leading server side scripting languages: PHP and ASP.Net PHP ASP.Net Microsoft Technology. Ships free with IIS on Windows OS. Open source language Runs on most OS Support windows only Slower compilation time Quick compilation and response time Hardware required to run PHP applications is expensive Windows licensing cost Not supported by any specific framework but has custom CMS such as Drupal and Magento Suppo rted by .Net framework which is very reliable Simple to code Complex to code Recommended for small applications Recommended for large applications Lesser data security Enhanced data security (Lerdorf & Tatroe, 2002) 2.3 - Database Management Systems A database management system (DBMS) is a software application that allows for the creation and management of a database. It also allows the users to make changes to the

Anti-Corrosion in Marine Surface Engineering

Anti-Corrosion in Marine Surface Engineering Surface Engineering: Coatings and Thin Films Technologies INTRODUCTION Surface building alludes to an extensive variety of advancements that plan to outline and change the surface properties of parts. There are two fundamental classes of surface designing techniques that can be utilized to advance the surface properties and the mass materials. These are surface coatings and surface Modifications. Other process include Surface shape design. Surface covering forms include protecting a layer of liquid, semi-liquid or substance material onto a substrate. One of the fundamental elements of surface covering is to change and fortify the surface capacities as opposed to improving the arrangement of the mass material. A few cases of surface covering forms incorporate Physical Vapour Deposition (PVD), Concoction Vapour Deposition (CVD), plasma and warm splashing, sol-gel, cladding and electroplating. Surface modifications procedures can be named solidifying by fire, acceptance, laser or electron bar, high vitality medications, e.g. particle implantation; and dispersion medicines, e.g. carburizing and Nitriding. Surface adjustment procedures are relevant to control rubbing, enhance surface wear and consumption resistance, and change the physical or mechanical properties of the part. Surface alteration medications additionally can be consolidated with surface covering forms, for example laser cladding. This blend improves the bene fits of surface coatings and surface adjustment, consequently accomplishing particular prerequisites and wellness for reason. Surface medicines that cause microstructure changes in the bulk material incorporate warming and cooling/extinguishing through acceptance, fire, laser, and electron bar strategies, or mechanical medications (one illustration is icy working). Surface medicines that modify the science of a surface incorporate carburizing, Nitriding, Carbo-Nitriding, Nitro carburizing, boriding, siliconizing, chromizing and aluminizing Hard facing is another type of surface treatment, where the mass material surface is given a defensive layer of another material having more predominant properties than those of the mass material. An example of this is covering a turbine pump seal joint with a destructive resistive material, to keep salty water from disintegrating the pump. Each strategy for hard confronting, cases of which are covering affidavit, cladding or welding, causes specific physical and concoction impacts on the mass material, some advantageous, some adverse. For instance focuses on which may exist in the defensive material can make issues, however watchful checking and research may restrain these impacts, to ideally create quality, serviceable building parts. The accompanying areas will portray the idea of surface building and the impacts designing situations have on these surfaces. Hard confronting procedures are portrayed in details particularly as to covering statement advances, with specific accentuati on on warm splash strategies, including the HVOF (High Velocity Oxy-Fuel) prepare that utilized as a part of the ebb and flow inquire about. 1.1 Surface Engineering At the point when two surfaces come into contact and relative movement is created, the contact stresses increased because of the generally little rate of load-supporting region. This will result in grating and wear, and potentially even prompt to disappointment. In the high anxiety utilizations of a present day motor or gearbox, there are zones where the weight of metal moving against metal powers away all the greasing up oil and permits warmth to develop. In the instance of extraordinary weight and contact, this warmth is sufficient to momentarily weld the two sections together just before they are broken separated by their development. This consistent weld and break handle which can happen at the nuclear scale bring about drag and wear, which are damaging. On the off chances that the riggings are the parts of a shuttle, and if the single part comes up short, the whole multi-million dollar shuttle would fizzle. So designed surfaces to battle grating and diminish wear is exceedingly alluring. Many materials have been developed to have specific bulk properties, although they have not been particularly optimized for the surface properties. Surface engineering can solve these problems by: Implanting alloying atoms to different depths, thereby improving toughness and fatigue properties; (surface modification) Depositing surface layers, thick or thin, including lubricants; (surface coating) Redesigning the surface shape of the component to distribute stresses. 1.2 Friction, Corrosion, wear Surface engineering techniques solve friction, corrosion, and wear problems. Friction, corrosion and wear are the most common factors that cause engineering failures. In industrialized countries, 7% of GNP represents the cost of friction, wear and corrosion, with the possibility of 1% of this figure being reduced through the use of efficient tribological systems. On a worldwide level, 34% of all lubricants produced are consumed in Europe, with 50% of this being recycled, with a further 2.5 million tonnes being lost in the environment. Corrosion is mainly an electrochemical phenomenon which occurs when metals react with materials in their environment. 1.3 Basic types of Corrosion and wear Fig. 1: Type of corrosion and wear Wear is the dynamic loss of material from a surface. Among the distinctive sorts of wear, rough wear and glue wear ordinarily happen more frequently than others. Grating wear is because of hard particles or hard bulges constrained against and moving along a strong surface. Cement wear is created by restricted holding between reaching strong surfaces prompting to material exchange between the two surfaces or the misfortune from either surface. Cement wear is a run of the mill case of how a delicate material can wear out a harder on. 1.4 Surface Engineering in Marine applications Methods of corrosion protection are based on the theory of corrosion processes. Alterations of the material properties and external environmental characteristics are the factors which can affect the slowing down or stopping of the corrosion process. Corrosion protection in the shipbuilding industry is an important technological process devised to protect the ship from corrosion effects. Even the storage area of plates, profiles and flats in a shipyard exposed to severe environmental conditions. Protection Coating in shipbuilding constitutes of following steps: Preparation of surface Temporary protection workshop Terms of coating Methods of Applying coating 1.5 Preparation of Surface Surface arrangement is a requesting innovative operation in the advancement of the ships body from essential surface readiness of plates, profiles, and pads performed in the programmed establishment .It likewise incorporates a fundamental workshop technique called covering. Shop groundwork in the film thickness 15-25 ÃŽÂ ¼m is utilized for the assurance of steel during the time spent ship development. In any case, compulsory control of the thickness of the coatings for more prominent thickness may unfavourably influence the cutting pace and nature of steel, and in addition the event of mistakes in welding. Optional surface planning is done in the corridors for sand impacting and painting, whereby soil and salt ought to be expelled from the surface of the area, rendering it and sandblasting as per standard ISO 8501-1. This innovative operation infers additional work in welding and crushing and speaks to the pre-gathering attachments. 1.5.1 Temporary protection of surface The principal phase of consumption assurance in the shipbuilding business comprises of the workshop covering (shop groundwork) on the plating profile and pads in a thin film, about of 15 to 25ÃŽÂ ¼m thick, as intemperate film thickness may adversely influence the nature of welding (the event of porosity) and cutting steel. Shop preliminary speaks to quick drying coatings which are utilized for transitory security of steel in the workshop amid ship development and utilization of the last covering framework. Transitory erosion security is performed in the workshop of preparing in mechanized plant beginning from drying sheets, shot impacting and covering as indicated by the ISO standard. Workshop coatings utilized are zinc silicate and epoxy press oxide shop preliminary. Epoxy press oxide is connected to acquire a more prominent thickness, requesting more paint, thusly bringing about higher coats and expanded misfortunes. Today in many shipyards zinc silicate is utilized as shop preliminary (with a share of 25-35 % zinc), which gives a superior quality welding and lessened event of undesirable zinc salts (a compound barely solvent in water and hard to clean from the surface) Shop preliminary must meet the accompanying prerequisites: It should be appropriate for mechanized re-coloring methodology, It have the most limited drying time (3 to 5 minutes), Imperviousness to high temperatures, It shouldnt discharge dangerous gasses amid welding and cutting, It shouldnt adversely influence the welding procedure It should not influence the mechanical properties of welded joints. 1.5.2 Terms of coating Surface readiness principles incorporate a few criteria, tenets and rules for the way toward get ready body metal surfaces. Surface states of steel structures are isolated into four phases: Steel surfaces secured with plant scale and little erosion, Steel surfaces, which have started to erode and from which process scale has begun to peel Steel surface displaying particles of rust or inadequately connected worrying factory scale with the main noticeable sings of setting, Steel surface that is unmistakably consumed and influenced by setting. The way towards planning metal surfaces done by different methods for abrasives. Abrasives are distinctive sorts of materials appropriate for the specific coarseness surface readiness, where the grating particles utilizing packed air are connected to the surface which is to be cleaned. 1.5.3 Method of Applying Coating The innovative procedure of erosion security utilizes diverse techniques for applying coatings by brush, roller or showering (air or airless), where the determination of the methodology influences the speed and nature of works. Paint brush is normally utilized for the methodology touch-up in the insurance of zones, for example, joints, moves, edges, welds and other unpleasant surfaces and setting. In these regions, color entrance is accomplished by applying the correct brushes: it cannot be accomplished by whatever other technique. Paint roller is seldom utilized in light of its deformities, arrangement of little uneven layers, more often than not with little crevices and openings. Applying a covering by splashing depends on scattering the paint as small beads that settle on the working parts. Airless splashing is a strategy that is most basic in the shipbuilding business since it empowers quick use of Paint onto extensive surface, high effect, the likelihood of applying thicker layer, and Great infiltration. ARC SPRAYING PROCESS Thermal spraying method is a process of coating in which a heated material is sprayed on its surface. This type of spraying can provide thick coatings over a large area at high deposition rate. Thermal spraying is classified into Plasma, Wire arc, Flame, Detonation, Warm and cold spraying. 2.1 Overview of Arc spraying process In electric arc spray process, two wires of desired materials act as electrodes are fed to spray gun at controlled feed rate. Compressed gas is also used to atomize and propel the material to the substrate. Fig.2: Schematic diagram of Wire arc spray device In this process, the anode and cathode wires are continuously melted and broken down into tiny droplets which are injected by air jets through a nozzle. The velocity of gas is a few hundreds of m/s but the gas is not heated, allowing operator to keep the substrate temperature below a few 0C without cooling. The arc powers generally range from 2 to 10 KW, airflow ranges from 0.8 to3 m3/min. The temperature of the arc can be as high as 20,000 k. DC generators are used a source for power. Before the arc process is performed, substrate surface is properly cleaned. For this purpose usually the surface is blasted using a compressed air abrasive blasting. This is effective for cleaning mill scaled on steel surface by using abrasive particle at high velocity and also for good adhesion of arc spray process. Along with this the substrate surface roughness is also important consideration to be made for proper coating bonding. To hinder rust formation and provide good bonding the coarse surface profile must be around 110 microns. Garnet is normally used abrasive as it can provide desired surface finish and roughness. As metallic abrasive usually result in energy being given off as a spark which might cause surface defect non -metallic abrasives are used. Fig.3: Arc spray process instrument Before the coating is applied on the substrate surface some conditions need to be satisfied, they are Surface finish must be greater than SA 2.5 as it can be visually inspected Surface roughness must range between 75 microns to 110 microns Permissible level for salt contamination of surface should not exceed 20 mg/m3 Dust level should not exceed the rating 1 2.2 Characteristics of Arc spray process Wire diameter: The wire diameter ranges from 1.6mm to 3.16mm. The deposition rate of coating on the surface depends on the wire diameter. Wire feed rate: This determines the rate at which the material must be introduced to the system, which is proportional to the rate at which the material introduced melts. Coating materials: Metals, cements, ceramics, polymers, carbides are some of the materials used for arc spray process. Solid wires produced from Chromium, zinc nickel based alloys or aluminum are generally used for arc spraying in marine application. Aluminum is considered to have the best performance for surface coating. Spray distance: The distance varies from 15cm to 25cm; the distance affects the deposition area of coating on the surface. Power requirement: Depending on the spraying material, voltage ranges from 16 V to 30 V. The applied voltage controls the input power to the arc which affects the rate at which the tips of the wires are heated and melted. The current is adjusted to 150 A for most of the applications. 2.3 APPLICATION OF ARC SPRAY PROCESS This process is mainly used for corrosion protection. Other than this, it is also applied for coatings of machineries like boiler tube, gear box, shafts and crankshafts in power plants. 2.4 ADVANTAGES AND DISADVANTAGES 2.4.1 Advantages Arc spraying process is economical when compared with other spraying techniques Any coating material can be used. Examples are ceramics, cement metals It has a high deposition rate of the thermal processes Operator requires less training The power requirement is also low Almost all substrate material can be coated Low porosity level can be achieved using this process Its useful as low heating of substrate makes arc spraying process useful in metalizing thermally sensitive substrate 2.4.2 Disadvantages Large amount of fume and dust is produced, which is a cause of concern for the operators health The materials used are limited to electrical conduction It can be sometimes seen that the coating quality does not meet to expectations as done with other technique 3. HOT DIP GALVANIZING 3.1 Overview of Hot Dip Galvanizing This process is used for coating iron an steel with a layer of Zinc by immersing the metal in molten zinc bath at a temperature of about 449 oC. This process forms a metallurgical bond between steel and molten Zinc and is done in a plant with controlled conditions. The bond formed has very good corrosion resistance due to the good molecular adhesion and the cathodic protection. The hot dip galvanization process mainly consists of 4 stages. Surface Preparation Removing oil/grease, dirt, paint etc. from the surface. Pickling in Acid To remove mill/scale. Flux Coating (Usually Zinc Ammonium Chloride) To prevent the oxidation of cleaned surface when exposed to air. Zinc Bath Dipping the material in Zinc bath and holding it until it reaches equilibrium with the bath temperature. Fig.4: Various steps in hot dip galvanizing method In HDG coating, the outermost layer (ETA) is a covering of pure zinc and is formed as the material is withdrawn from the molten Zinc bath. The underlying series of layers (of coating) are zinc-iron alloys and are formed as a result of metallurgical reaction between the molten zinc and the material being galvanized. In HDG process, the coating formed on the corners and edges of the material is generally thicker than the surrounding coating. The reason for this is that the zinc-iron alloys formed would grow perpendicular to the steel surface. The ETA layer is ductile and provides good impact resistance to the galvanized material. The combination of all the layers in the coating provides toughness to the material and also aids in resistance to mechanical damage in transport, erection and service of the components. Fig. 5: Typical cross section of a hot dip galvanized coating 3.2 Variable Parameters The appearance and the thickness of the galvanized coating are affected by several factors. Steel Composition: The galvanizing reaction produces thicker coatings for rough steel surfaces because of the increased surface area and also these coatings would have a poor appearance and would be a rough coating. Bath Immersion time: As galvanization is a diffusion process, the reaction between molten zinc and steel would be quick initially but slows down as the alloy layers grow and become thick. So, continuous immersion or dipping of the material more than once doesnt produce a significantly thicker coating. (Which happens in case of reactive steels) Speed of Withdrawal: The withdrawal rate of material from the galvanizing bath has a significant effect on the outermost layer of the pure zinc. Thickest coating would be formed when the withdrawal is rapid because this allows a large amount of zinc to be carried out on the material which would eventually solidify and become pure zinc layer. On contrary, smooth, thin and uniform coatings are formed with slower withdrawal rates as it allows the zinc to drain back into the kettle. Steel cooling Rate: The dull or matte gray coatings are usually due to slower cooling rates such as air cooling or quenching of thicker sections because the slow cooling would allow the zinc-iron alloying reaction to continue and the inner alloy layers would use the outer ETA layer for their zinc supply. The formation of dull/matte surfaces can be reduced by halting the galvanizing reaction by quickly reducing the temperature to less than 300oF. 3.3 ADVANTAGES AND DISADVANTAGES 3.3.1 Advantages Lower first cost: This process generally has the lowest first cost compared to any other protective coatings for steel. The application cost of painting which is a labor intensive coating has risen far more than the cost of factory applied hot dip galvanizing. Lower maintenance / lower long term cost: In some cases, the initial cost of hot-dip galvanizing is higher than alternative coatings, but it is more cost effective due to its lower maintenance costs during long service life. Maintenance is costlier for structures in remote areas. Maintenance programs have an invariably negative impact on productivity. Long Life:In hot dip galvanized coatings, the life expectancy of structural members is 50 years more than in more rural environments and 10 to 30 years in most corrosive urban and coastal environments. Surface preparation:To ensure uniform cleaning of steel surfaces,they must be immersed in acid whereas organic coatings must be applied on abrasive blast cleaned surfaces and should be verified by third party inspection. Adhesion: This coating is metallurgical bonded to the steel surface. Environment friendly:The coating is non toxic and doesnt contain any volatile substances. Speed of coating application:A full coating can be applied in minutes whereas multi paint coating system takes up to a week. The application of hot dip galvanized coating is not influenced by weather conditions. Uniform protection:Hot dip galvanized surfaces are protected both internally and externally including recesses, sharp corners and inaccessible areas for application of other coating methods. The coating is at least as thick over sharp corners as on flat surfaces. No other coating applied can provide similar uniform protection. Sacrificial protection for damaged areas:A hot dip galvanized coating would preferentially corrode to steel providing cathodic protection to small areas of steel exposed to damage. Toughness:A hot dip galvanized coating has outstanding resistance to mechanical damage during transport, erection and service due to its unique metallurgical structure. Disadvantages This process can only be carried out in a galvanizing plant and on site application is not possible. The color of the zinc coating can only be changed by painting the coated surface. The size of the zinc bath is a limiting factor for the component or structure dimensions. There is probability of distortion/warp of large flat unsupported sheet components and long, slender beams due to the high molten zinc temperature. The welding of the zinc coated steel would need different procedures as compared to the uncoated steel. During welding of hot-dip galvanized steel, there is a loss of coating in the first and second heat affected zones, but a portion of the coating remains right up to the edge of the weld. COMPARISON OF ARC SPRAY PROCESS AND HOT DIP GALVANIZING FOR COATING OF SHIP HULL As studied in the sections before both Arc Spray Process and Hot Dip Galvanizing has their advantages and disadvantages. In this section we will compare both these process based on important characteristics and try to find out which one would be a better suitable process for coating of ship hulls. 4.1 Surface Preparation Hot Dip Galvanizing requires specific surface preparation consisting of Degreasing, Pickling and in Flux solution, not only these surface preparation method requires special setup, but processes such as Pickling can introduce Hydrogen in the substrate causing Hydrogen embrittlement and Hydrogen Induced Cracking, however if the substrate steel is not cleaned properly the zinc will not bond with it and it may be noticed at that stage only. Surface preparation for Arc Spray requires the surface to be little coarse which can be done by abrasive air blasting which depends on the operators experience, but if the cleaning is not done properly it may not be detected then. Thus surface preparation by Hot Dip Galvanizing is advantageous. 4.2. Coverage Arc spray process cannot be used for coating of corners, edges and complex shapes such as threads and hollow section, all of which can be coated easily by hot dip galvanizing as it is a dip process. Since ship hulls are large bulky object which doesnt have any such complex shape both processes can be used here but still Hot Dip Galvanizing will be more beneficial. 4.3. Process Time and Economy Hot Dip Galvanizing takes less time as it can coat almost all the surface area at one go when dipped inside the bath whereas Arc spray process is a line by line process and hence takes more time. The equipment cost for arc spray is lower, its setup is also easier than Hot Dip Galvanizing, and the equipment is mobile whereas the baths for Hot Dip Galvanizing is stationary but this method can cover large area at one go. Therefore for coating of ship hull, Hot Dip Galvanizing is a faster process as they have a very large surface area for which Arc Spray process will take more time and the higher cost of Hot Dip Galvanizing is negated by ability to cover larger surface area at one goes. 4.4. Effect on Substrate For Hot Dip Galvanizing the baths are maintained at a temperature of around 450ÂÂ °C which is just below the austenitizing temperature of steel and hence may cause a change in microstructure of the substrate if there are some variations whereas since no hot jet is directed on the substrate in the arc spray process there is no effect on the underlying substrate. Thus only considering this effect on substrate thermal arc spray process is a better process. 4.5. Coating Thickness The thickness of coating in electric arc spray coating can be regulated by regulating the speed of wire feed in the process, thus it can be easily controlled whereas in Hot Dip Galvanizing a certain thickness may not be specified as the thickness depends on the withdrawal speed which may cause an uneven distributed coating. 4.6. Bond Strength The bond strength for arc spray process for ferrous and non ferrous alloys is within the range of 4000-7000 psi whereas for Hot Dip Galvanizing the bond strength is around 3600 psi, thus arc spray process provides comparatively higher bond strength. 4.7. Hazard Fumes and other hazardous by products are formed during the Hot Dip Galvanizing can pose health hazard to the operators who are working in the shop floor as well as to the environment. Thermal Arc Spray process on the other hand produces metallic dust consisting of very fine particles and fumes; also electric arc spray process operates at high current which can result in shock hazards if not treated with caution. Clearly both processes are hazardous both to human as well as environment. 4.8 Conclusion for comparison Considering all the above factors Hot Dip Galvanizing seems to a better and efficient process for coating of ship hulls, not only coating ship hulls which have large surface area by arc spray a time consuming task it doesnt providing any other significant advantages as compared to Hot Dip Galvanizing. CONCLUSION In this report, we have mentioned the different possibilities for anti-corrosion in marine environment. Here we have taken the two commonly used methods for the protection of ship hull from corrosion. As the instrument for arc spray process is quite cheaper compared to the other techniques, its widely used in marine industry. The coating adherence is good with no heating of the substrate generally; however coating done by this method is porous. The hot -dip galvanizing process is an effective way for resisting corrosion. It is a simple process with better service life. It gives high quality with low environmental pollution making it a good competitive method. After comparing the two methods, we can conclude that arc spray process is used if we want good control and for better quality, on the other hand hot-dip galvanizing is used for mass production as it turns to be economical. 6. REFERENCES [1] Muhamad Hafiz Abd Malek, Nor Hayati Saad, Sunhaji Kiyai Abas, Noriyati Mohd Shah, Thermal Arc Spray Overview, IOP Conf. series: Material science and engineering 46 (2013), doi:10.1088/1757-899X/46/1/012028 [2] M.F.O Schiefler Fiho, A.J.A Buschinelli, F.Gartner, A.Kirsten, J.Voyer, H.Kreye, Influence of process parameters on the quality of thermally sprayed X46Cr13 stainless steel coating, COBEF 2003- Brazilian Manufacturing Congress, 18-21 May 2003, Vol.XXVI, pp 98-106 [3] Website http://www.environment911.org/Environmental_Issues_With_Galvanizing [4] Website http://www.galvanizeit.org/education-and-resources [5] Website https://www.scientific.net/AMR.685.271 [6] Website https://www.upc.edu/sct/en [7] Website http://www.mbicoatings.com/content.cfm/Coatings/Arc-Spraycoatings/ category id/102/page id/170 [8] Website http://www.aeromac.com.sg/thermalsprayadv.html [9]Website http://www.metalplate.com/techdept/characteristics.php [10] Website https://www.canam-construction.com/wp-content/uploads/2014/12/2012-12-hot-dip-galvanization-of-structural-steel.pdf

Free College Admissions Essays: Art is My Life :: College Admissions Essays

Art is My Life From an early age I have always had a strong interest in art, and have been involved with it in some form all through my life. In year nine I realized that it was something that I might like to pursue as a career, I started taking it more seriously. The Chase's art department encouraged me very well and helped me develop my art skills. I am currently studying Art at A-level and have had my work exhibited in a gallery and in local industry buildings as part of the 'Art in the Workplace' scheme which is organized by my college. The piece of my artwork which was displayed, and used in a business's workplace was a painting inspired by an Art Department trip to Italy. In my spare time, I enjoy running my own comedy website with my friends, which has enabled me to learn good organizational skills. Aside from art, I enjoy playing basketball with other students from my college every Wednesday afternoon. I have found this to be a welcome break from normal study, allowing me to exercise at the same time as relieving stress. My present interest in art is more graphic/typography based, although I do enjoy all areas of art. I have been designing graphics on my computers from a young age and have work published in national magazines. Not all the graphical work I do is computer based, I enjoy using traditional mediums in a clean graphical way, as I find it more satisfying working on a larger scale and producing something more "real". My current course has helped me "branch out" more; I have experimented in many disciplines successfully producing paintings, pastels and drawings, which I had never really developed fully before. I have had two part-time jobs involving computer related work, in which I have been able to bring art influences into. When working for Retail Futures, an e-commerce company based in Malvern, I designed their corporate image, and websites for clients such as Coalport and Parcel Force. More recently I have taken another job with a more technical slant, for another e-commerce firm, eplexus. I still do design work, in which I have designed websites and images for "Highwaycode.com", and Anglo Digital a successful venture capitalist firm. Alongside my practical experience, I am also studying Computing at my current college, which aids me to learn the fundamentals of computer usage and programming, an area that I am interested in.