Love Assignment Example | Topics and Well Written Essays - 500 words

Love - Assignment Example In addition, the program seeks to expand the leadership abilities of individuals through adoption of programs that are focused at bringing change within the community. The program covers education institutions including colleges and universities. Chesapeake Bay Program awards an average of $1 million. In addition, the grant funds 20% of applications. Depending with the financial requirements of a project, Chesapeake Bay Program offers the funds for one year. Individual or institutions in need of grants can access the funds 6 to 8 months after the issuance of the request for proposal. The grant requires that a cost share of 25% of the total costs as stipulated by the project budget (2012-2013 Guidelines for Financial Support Grants). Online or mail applications can be used to apply for Chesapeake Bay Program grant. Source Reduction Assistance Grant Program is another key source of funds. The program covers clubs and organizations, communities groups and local organizations that aim at eradicating the toxic substances used by young people. With an annul award of between $1.1 million-$1.7 million, the program funds 15% of the grant applicant. In addition, projects are funded in annual bases. According to Source Reduction Assistance Grant Program, recipients of the grant should provide 5% of the allowable project cost that can be inform of in-kind contributions such as equipments or in form of cash (Samuel, 2007). Application for Source Reduction Assistance grant can be done online or through mail after which the successful applicants receive Grants between May and

Ap American History Essay Example for Free

Ap American History Essay 1. â€Å"The opponents of the annexation of Texas and the Mexican War attacked slavery as the root cause of expansion, but in fact it was no more important than other causes.† Assess the validity of this statement, using the documents and your knowledge of U.S. history from 1820-1860 to support your answer. During the early-mid part of the 19th century (mainly 1820-1860) Americans objected many things they didn’t like. Taxes, the government, even presidents were some of the rejections of the people. But the one thing the people did not like during this time period was the annexation of Texas and the Mexican War. â€Å"The opponents of the annexation of Texas and the Mexican War attacked slavery as the root cause for expansion.† However, slavery was not the only reason America sought for expansion. Other than slavery, people wanted to expand America because they believed in Manifest Destiny (an idea during the 19th century in which people believed that America should expand over the entirety of North America) or because they feared that Texas was an independent state, even the Gold Rush in California (1848-1855) contributed to the expansion of America. Even though â€Å"the opponents of the annexation of Texas and the Mexican War attacked slavery as the root cause of expansion† the idea of Manifest Destiny, fear, and the Gold Rush were other important causes for expansion. As you may know, slavery was the key reason as to why people wanted to expand America, especially southerners. Abolitionists (people who were against slavery) did not like the idea that the expansion of America was based on slavery, but it was. In Document B it states, â€Å"Texas†¦will strengthen ‘the peculiar institution’ of the South, and open a new and vast field for slavery.† Many southerners wanted Texas to be annexed to America because it would allow the south to have more slave states (states that allowed slavery). However, people feared that if Texas was annexed, slavery would expand everywhere in America, and they did not want that. Document C also talks about slavery. It states that, â€Å"The slave population of America†¦must be increased.† Texas is annexed; it will benefit the South in moving some slaves out of the â€Å"superabundant slave population† and will ultimately improve the living conditions of slaves because they wou ldn’t be as crowded. You see, slavery was an important cause for expansion, but the idea of manifest destiny was just as important. The idea of manifest destiny came about the early part of the 19th century. People who believed in manifest destiny believed that America should be able to expand to the entirety of North America. In Document A, Thomas Hart Benson says, â€Å"†¦the American population has begun to extend itself to the Oregon [Territory]†¦I say to them all, Go on!† People like Mr. Benson want America to expand because they want the world to show the world how prosperous America is. In Document D, John L. O’Sullivan said, â€Å"A population will soon be in actual occupation of California.† In this document, Sullivan was talking about the California Gold Rush (1848- 1855). Since many people on the eastern side of America have been hearing about the sightings of gold in California, many people decided to venture out to California to collect some of it. Thousands of people rushed to California that it was given the term â€Å"gold rush†. The gold rush allowed America to expand itself into California, which was supported by the manifest destiny believers. Document E also talks about the ideas of manifest destiny. It states, â€Å"We ought to have the Bay of San Francisco! Why? Because†¦I think†¦our people [should move there]!† The author of Document E obviously believed in the idea of manifest destiny because he wants to see people in San Francisco, which is in California. The manifest destiny idea helped encourage people to have more pride in their nation, which allowed them to expand from the East coast of America to the West. However, not every idea of expansionism was happy. Others people wanted to expand America because of fear. In Document F it states, â€Å"None can fail to see the danger to our safety and future peace if Texas remains an independent state, or becomes an ally or dependency of some foreign nation more powerful than herself.† After Texas won its independence from Mexico in 1835, Texas could not cede the American Union because it needed to enter America with a free state (a state with no slavery) because of the Missouri Compromise (the Missouri Compromise was passed in 1820 in which stated that there would be no slavery in the Louisiana Territory above the 36th parallel). Since there were no other states to enter with Texas, Texas had to remain as an independent state for about ten years (1835- 1845). During that time, people urged for a state to enter as a free state with Texas because, since Texas was not a part of America, it could do whatever it wanted. Things like joining a d ifferent nation or starting a war with America were options that were available for Texas. That is why many people wanted Texas to join as quickly as possible. Thankfully, Texas joined with Iowa in 1845. You see, slavery was not the only cause for expansion in America. The idea of Manifest Destiny and fear allowed the expansion of America, even the Gold Rush encouraged people to settle in California, allowing America to expand from the east coast to the west.

Does Money Buy Happiness?, by Don Peck and Ross Douthat :: Money and Happiness Essays

Erika’s sweet sixteen is today, and her parents bought her a brand new car. She pulls into the school’s parking lot and flaunts about how her parents not only got her a car, but also a trip to Italy. People start to walk away, even some of her best friends. As the day goes on, her friends have not talked to her since morning. Fed up, Erika asks them what is wrong. Kristie, one of her friends, tells her how they cannot stand listening to her talk about her ostentatious gifts anymore. When Erika gets home from school, her mom asks her what is wrong. It is then she realizes what her friends were trying to say and tells her mother she does not want the car anymore. Her mother, astounded, asks why not and gets a reply of money cannot buy friends, nor can it buy happiness. According to â€Å"Does Money Buy Happiness,† by Don Peck and Ross Douthat, they disagree with the connection between money and happiness. Happiness is a feeling adults experience when they receive a gift, win something, and various other reasons, but does money buy this happiness everyone experiences? Don Peck and Ross Douthat claim money does buy happiness, but only to a point in their article which originally appeared in the Atlantic Monthly (252). Throughout their article, reasons on why money can sometimes buy happiness are explained. While some of the reasons given are effective, not all are satisfying answers for adults working diligently to make a living. Money is a part of everyone’s life, yet it is not always the cause of happiness. One reason described to be a cause of happiness is income. Don Peck and Ross Douthat indicate how, â€Å"National income appears to be one of the best single predictors of overall well-being, explaining perhaps 40 percent of the difference in contentment among nations† (352). With this statement, comes the explanation of how income can influence happiness in adults who strive to earn a living. Research illustrates how, â€Å"For individual countries, with few exceptions, self-reported happiness has increased as incomes have risen† (Douthat 352). While these two statements provide sufficient evidence for the reason of income bringing happiness, income itself is not relevant.

A Study on the Neuroscience of Learning

The research to be carried out purposes at set uping the importance of neuroscience of larning in instruction and single development ; this means that effectual educational policies and patterns are prepared to give room for all the people to larn despite their acquisition challenges. it besides brings out how the encephalon develop during the childhood phase up to the maturity and the factors that influence their acquisition of which assorted steps may be devised to turn to them, for larning to be of importance to the person and the society as a whole. The research to be undertaken hence, ought to reply the undermentioned inquiries ; -How does neuroscience of larning impact on instruction direction and development? -What are the factors that influence neuroscience of larning? -How can neuroscience of larning be enhanced for larning to be effectual? Neuroscience is a field which deals with the survey of the human encephalon and the nervous system. It besides entails the biological footing of perceptual experience, acquisition, memory and being witting. The nervous system and the encephalon signifier the footing of the human acquisition. Learning on the other manus harmonizing to Koizumi refers to a procedure by which the encephalon reacts to stimuli by doing neural connexion that act as an information processing circuit and supply information storage In contrast, Coffield from the instruction research proposes that larning refers to important alterations in capableness, apprehension, attitudes or values by single groups, organisations or a society. Neuroscience of larning helps the stakeholders involved in instruction sector to come up with sound policies and they can plan a course of study which suits kids harmonizing to the demands. It besides grants an chance for early designation of kids with particular demands and facilitates the proviso of particular instruction in the state. ( Centre for Education Research and invention 2007 ) Neuroscience hence investigates how our encephalons learn, retrieve and maintaining what we learn repeatedly. Fruitious acquisition is influenced by the context provided by category suites and households, the course of study in topographic point and the instructors. Therefore, neuroscience of larning provides elaborate history of how scholars respond to different acquisition attacks and the acquisition methods, and how the environment influences the single acquisition procedure. The more we learn and know about our encephalons, we can utilize the same cognition in bettering the acquisition procedure in larning establishment right from preschool to the university degree.1.2 Specific aims-To set up the impacts of neuroscience of larning in instruction direction and development – To happen out the factors that influences the neuroscience of acquisition. – To happen out ways of enhance neuroscience of propensity.1.3 Research inquiries-How does neuroscience of larning impact on instruction direction and development? -What are the factors that influence neuroscience of larning? -How can neuroscience of larning be enhanced for larning to be effectual?2.0 THE LITERATURE REVIEW2.1 The encephalon development in neuroscience of larningHuman encephalon develops otherwise throughout his/her life clip that is from childhood to adulthood. Changes in human encephalons influences larning and as such different thing can be taught at different period in life.2.1.1 At the early phase of lifeThis is a suited age for larning because of the undermentioned grounds attributed to the encephalon: the procedure of synapses fabricating and neuron connexions is go oning at a higher in kids than during maturity. In this phase synaptic pruning occurs and as such this makes larning possible for the immature kids as there are a batch of alterations in their encephalons. Sniping and synaptogenesis have been coined from researches done on monkeys which show that these procedures occur early plenty in kids meaning that when a kid is three old ages old, it means that it is a good clip for larning. Second, it is the period in which a kid can larn a peculiar accomplishment or develop certain abilities. This explains why immature kids can bring forth and articulate words clearly than grownups since immature kids involve motion, memory and their ocular rudimentss that are learned of course. Last, are the effects of the improvished and enriched larning environment for illustration schoolrooms. The improvished environments are known to impact cognitive and nervous development.2.1.2 Brain development at the vernal phaseNeuroscience shows that the encephalon continues to develop even during adolescence period. This development occurs in largely in the parietal cerebral mantles and the bow portion where the synaptic pruning does non get down until after this period. Another alteration happening in these encephalon parts is the myelination which is the procedure of where axons relay the messages from and to the nerve cells and besides they become insulated medulla which is a fatty compo nent found in the encephalon. The insularity of the nerve cells increases its efficiency of relaying information in the encephalon. in these parts myelin procedure additions bit by bit throughout the period and besides to early adulthood easing the addition in the velocity of communicating of the neurals in these parts of the encephalon. Synaptic pruning continues to happen and as such it gives the teens the possibility of hive awaying batch information in their head because they activate many parts of their encephalons when larning equations in mathematics for illustration the algebraic 1s2.1.3 Brain development in the grownup phaseChanges happening are non much as those during childhood, the encephalon will go on to develop and alter even if there is addition in age. In this phase, the encephalon becomes less elastic and it commences losing the nerve cells at a faster rate. The neurogenesis besides occurs in one part of the encephalon significance that it is good prepared for unin terrupted acquisition and makes it able to accommodate to new state of affairss, twenty-four hours to twenty-four hours happenings and experiences that may hold important impacts to life.2.2 Factors act uponing neuroscience of larning2.2.1 The environmentHarmonizing to researches that have been done earlier, fostering of the encephalon plays a centre function in the acquisition procedure. It has besides provided the educationalists the information on the appropriate timings for different scholars set abouting assorted materials. Therefore, the procedure of fostering encephalons is non the same for every scholar because of the varied familial make- ups and the surrounding scholars are exposed to. The acquisition encephalon is hence, dependant on these two factors since it readily adapts to an environment easy. There is a close-link between the encephalon construction and the experiences it comes across. Experience is known to do alterations in the construction of the encephalon which in bend impacts on the effects that the predating experience has on the encephalon, this explains why there is single larning difference in our society which comes as a consequence of cumulative and uninterrupted interactions between the encephalon familial make up and the surrounding. The surrounding in which a scholar is exposed to impact the look of cistrons related to larning throughout 1s ‘ life-time. The end point therefore, affects the subsequent experience- elicit familial look. It is in this mode that each independent encephalon accumulates structural foibles which has impacted on the acquisition procedure, intending that it is hard to come up with an ideal environment for each scholar. Therefore, the acquisition environment is of great significance as it shapes the acquisition procedure. By understanding emotional and physiological procedures, educational and developing programmes can be designed to help in development of emotional intelligence so as to heighten larning capacity of the encephalon. It besides adds to specifying age appropriate schemes for modulating emotions. This means that parents and instructors embark on a pang lupus erythematosus environment for the scholars to grok and show their emotions clearly.2.2.2 Personal factorsThe esthesis and perceptual experience elements of a human being affect 1s larning, since the centripetal variety meats are the gateway of comprehending stimulations within the environment and acquisition. Therefore, if a scholar has a defect in one these centripetal organ larning because hard, for person who has a hapless oculus sight means that he/she can non cook clearly. Second, fatigue besides decreases encephalons ‘ efficiency in acquisition and has such if one is tired hold oning something is trouble. This is accompanied by ennui which makes one non to hold that impulse of larning. Third, neuroscience of acquisition is influenced age and adulthood of the person, kids can larn at earlier age than others and increase the age means that a scholar can work out jobs and can modulate his/her emotions. Fourthly, demands affect neuroscience of larning since there are basic demands which kids can make without. For illustration, nutrient, fondness and acknowledgment, without these turning kids are affected in a figure manner which deter them from larning and alterations their normal behaviour. Starving hapless kids concentrate less on larning than their opposite numbers who have sufficient nutrient. Last, motive has a human factor influences neuroscience of larning since it is the Centre of larning which drives a scholar to make something now and once more. When scholars are adequately motivated, larning is directed and engages pupils to activities which result in a uninterrupted acquisition.2.3 Contributions of neuroscience of larning towards instruction.From research workers done, instructors say that neuroscience of larning contributes to the apprehension of the schoolroom since instructors are enthusiastic about larning. It leads to the apprehension of the encephalon constructs and other constructs of larning. Neuroscience of acquisition has made instructors to understand and develop involvement in the figure of scholars holding psychological jobs, growing and development jobs. Guy Glaxaton suggested that instruction has been an unbarred field because of the dangers of enthusiasm. He said that educational jobs have to be justified and is to be done must be rationalized. the concerns of other educationalists is that they see that there is demand for moderateness between sense of cautiousness and the optimism that each stakeholder in the instruction sector has, this is for the acquisition to something of value. In general neuroscience of larning aids in job resolution. It provides the necessary information to the edifice of the educational theories and pattern. This is attributed to the fact that behavioural scientific discipline entirely is non equal plenty to used in finding if the development dyslexia is a upset of the primary ocular or that emanating from the phonological facet of the acquisition. On other manus, neuro-imaging which is a constituent of neuroscience of acquisition has aided in uncovering the reduced activation for the scholars with dyslexia job in the encephalon that supports the processing of the phonemics hence perpetuating behavioural mentioning of the phonological theory of dyslexia. Therefore, for kids or scholars with this job who receive good educational intercession may stop up altering. The activation forms of their encephalons may alter and look like those of people with no encephalon upsets. In relation to this, the encephalon parts may besides move as mechanisms for compensation. This assists instructors and other educationalists to understand that even if scholars holding dyslexia job better their behaviours, cognitive and nervous response by which they process written information still may be different taking to practical deductions on the given instructions during the learning procedure. There is clear groundss that neuroscience of acquisition is important in the linguistic communication development, mathematics and other facets of acquisition and literacy. Language is a cardinal thing in the production of unwritten work and academic attainment. Children who have linguistic communication jobs pose challenges on the readying of the educational policy and its execution in a state. The earlier these jobs are noticed the earlier the intercessions are made to help the acquisition environment particularly the schoolroom for it to ease linguistic communication development, which an indispensable constituent in kids ‘s live. Without proper educational intercessions it means that the person, the parent and the state ‘s ‘ economic system is affected negatively.DecisionFrom the literature reappraisal neuroscience of acquisition is a cardinal field which affects single acquisition and the instruction policies in a state. Neuroscience of larning reveals the impo rtance of the encephalon in the acquisition procedure and its development through homo ‘s growing. Neuroscience has hence helped educationalists to turn to the demands of kids with developmental jobs. The factors that influence neuroscience of larning have different impacts on the acquisition procedure and as such remedial steps have to be taken to heighten or to extinct their influence for larning to be effectual.

Night World : Huntress Chapter 3

Jez burst through the door and turned immediately into the small library off the front hall. Her uncle was sitting there at his desk, surrounded by built-in bookcases. He looked up in surprise. â€Å"Uncle Bracken, who was my mother? How did my parents die?† It all came out in a single rush of breath. And then Jez wanted to say, â€Å"Tell me the truth,† but instead she heard herself saving wildly, â€Å"Tell me it's not true. It's not possible, is it? Uncle Bracken, I'm so scared.† Her uncle stared at her for a moment. There was shock and despair in his face. Then he bent his head and shut his eyes. â€Å"But how is it possible?† Jez whispered. â€Å"How am I here?† It was hours later. Dawn was tinting the window. She was sitting on the floor, back against a bookcase, where she'd collapsed, staring emptily into the distance. â€Å"You mean, how can a vampire-human halfbreed exist? I don't know. Your parents never knew. They never expected to have children.† Uncle Bracken ran both hands through his hair, head down. â€Å"They didn't even realize you could live as a vampire. Your father brought you to me because he was dying and I was the only person he could trust. He knew I wouldn't turn you over to the Night World elders.† â€Å"Maybe you should have,† Jez whispered. Uncle Bracken went on as if he hadn't heard her. â€Å"You lived without blood then. You looked like a human child. I don't know what made me try to see if you could learn how to feed. I brought you a rabbit and bit it for you and let you smell the blood.† He gave a short laugh of reminiscence. â€Å"And your little teeth sharpened right up and you knew what to do. That was when I knew you were a true Redfern.† â€Å"But I'm not.† Jez heard the words as if someone else was speaking them from a distance. â€Å"I'm not even a Night Person. I'm vermin.† Uncle Bracken let go of his hair and looked at her. His eyes, normally the same silvery-blue as Jez's, were burning with a pure silver flame. â€Å"Your mother was a good woman,† he said harshly. â€Å"Your father gave up everything to be with her. She wasn't vermin.† Jez looked away, but she wasn't ashamed. She was numb. She felt nothing except a vast emptiness inside her, stretching infinitely in all directions. And that was good. She never wanted to feel again. Everything she'd felt in her life-everything she could remember-had been a lie. She wasn't a huntress, a predator fulfilling her place in the scheme of things by chasing down her lawful prey. She was a murderer. She was a monster. â€Å"I can't stay here anymore,† she said. Uncle Bracken winced. â€Å"Where will you go?† â€Å"I don't know.† He let out his breath and spoke slowly and sadly. â€Å"I have an idea.†

Lost Foam Casting Essays

Lost Foam Casting Essays Lost Foam Casting Paper Lost Foam Casting Paper LOST FOAM CASTING ABSTRACT: The Report presents some theoretical and practical aspects regarding the casting of alloys in lost foam moulds. The stages of the procedure, the economic benefits and several ecological aspects are synthetically presented. KEY WORDS: casting, alloys, lost foam process, Expanded polystyrene Introduction The lost foam casting process offers several advantages over conventional sand casting processes, such as simplified production techniques and reduced environmental waste due to binder system emissions and sand disposal. The process is well-suited for castings with complex geometries, tight tolerances, and smooth as-cast surface finish requirements. When the castings are designed to fully exploit these advantages, cleaning and machining times are dramatically reduced if not completely eliminated. Therefore, the lost foam casting process is viewed as a value-added process rather than a substitute for sand casting. Lost foam castings are produced by pouring molten metal into a foam pattern contained in a flask filled with loose sand that is compacted through vibration. Generally speaking, a foam pattern is coated with a refractory slurry and dried before being placed in the flask and surrounded by large grain fineness sand. The foam pattern degrades immediately after molten metal is introduced, leaving a casting that duplicates all features of the foam pattern. The degradation products are vented into the loose sand. In lost foam casting process, mold filling, thermal transport, and solidification are strongly influenced by the foam pattern degradation. There are three phenomena which are inherent in lost foam casting process: slow molten metal flow, reducing atmosphere, and degradation products. The first and second phenomena help reduce oxides or slag defects. The last one, however, may become casting defects if they remain in the cast parts. To improve lost foam casting design, it is ssential to understand the interactions between the foam pattern and molten metal as well as the displacement of degradation products. History The first patent for an evaporative-pattern casting process was filed in April 1956, by H. F. Shroyer. He patented the use of foam patterns embedded in traditional green sand for metal casting. In his patent, a pattern was machined from a block of expanded polystyrene (EPS), and supported by bonded sand during pouring . This process is now known as the full mold process. In 1964, M. C. Flemmings used unbonded sand for the process. The first North American foundry to use evaporative-pattern casting was the Robinson Foundry at Alexander City, Alabama. General motors first product using these processes was the 4. 3L, V-6 diesel cylinder head, which were made in 1981 at Massena, New York. A study found in 1997 that evaporative-pattern casting processes accounted for approximately 140,000 tons of aluminum casting in the United States. The same survey forecast that evaporative-pattern casting processes would account for 29% of the aluminum, and 14% of the ferrous casting markets in the near future. Definition Definition| A casting process whereby the pettern is made of polystyrene foam and is vaporized when the mold is fill with molten metal| Lost form consist of first making a foam pattern having the geometry of the desire finish metal| Expanded polystyrene casting use a mold or sand park around a polystyrene pattern that vapourizes when the molten metal is poured into the mold| Evaporating pattern casting (lost foam) : this process is also know as lost pattern casting under a trade name â€Å"full mold process†, it use a polystyrene pattern which evaporate upon contact with molten metal to form a cavity for the casting| Lost foam casting, where the mould cavity is filled with polystyrene foam (the ‘full mould’ process) , is a special case. | What is â€Å"Lost Foam†? The Lost Foam casting process originated in 1958 when H. F. Shroyer was granted a patent for a cavity-less casting method, using a polystyrene foam pattern embedded in traditional green sand. The polystyrene foam pattern left in the sand is decomposed by the poured molten metal. The metal replaces the foam pattern, exactly duplicating all of the features of the original pattern. Like other investment casting methods, this requires that a pattern be produced for every casting poured because it is evaporated (â€Å"lost†) in the process. Schematic of lost for casting Process The essential steps of the lost foam casting procedure are: 1) The execution of patterns, 2) Execution of moulds 3) casting the alloy. Execution of Patterns: A pattern is made from  polystyrene foam (Expanded Polysterene), which can be done many different. What is Expanded Polystyrene? Expanded Polystyrene in its broadest sense is a rigid cellular plastic which is found in a multitude of shapes and applications. Raw Material Manufacturing: Expanded polystyrene (EPS) is the most commonly used foam pattern, it can be produced by bead pre-expansion into polystyrene (PS) beads that are ready for moulding. PS precursors are formed from ethyl benzene through an aluminum catalyst with benzene and ethylene obtained from crude oil and natural gas [Shivkumar, 1994]. Ethyl benzene is then converted to styrene at high temperature with nitrogen gas and iron catalysts. It forms polystyrene when exposed to a peroxide catalyst and polymerized in a water solution [Goria et al. , 1986]. These unexpanded beads have a density of 600 g/l (38 pounds per cubic feet (pcf)) and they are expanded 20~50 times with heat at 100 oC until the desired density is reached [Kanicki, 1985]. Polystyrene (PS) MOLECULAR FORMULA: The C=C double bond in each monomer is transformed into a C-C single bond in the polymer. | Properties: ease of forming, clarity, low heat transfer, good thermal insulation. Density: 1. 03-1. 06 g/ccStatistic: In 1999 PS usage as a plastic bottle resin was essentially nil. | Description: Polystyrene can be made into rigid or foamed products. It has a relatively low melting point. Packaging applications: Plates, cups, cutlery, meat trays, egg cartons, carry-out containers, aspirin bottles, compact disc jackets Recycled products: Thermal insulation, light switch plates, egg cartons, vents, rulers, foam packing, carry-out containers Raw Material Manufacturing: Expanded Polystyrene (foam)  is obtained from expandable polystyrene (beads), which is a rigid cellular plastic which contains an expansion agent. Expandable polystyrene is therefore obtained from oil as can be seen from the diagram. The EPS Manufacturing Process is inextricably linked with the process described in the last section, which brought us from the oil well to expandable polystyrene, now we will see what happens in the transformation process that leads us to Expanded Polystyrene foam parts. We have seen that the raw material is obtained through a chemical process. The next process involves the use of physics and the conversion process is carried out in three stages. 1st stage   PRE-EXPANSION: The raw material (beads)  is heated in special machines called pre-expanders with steam at temperatures of approximately 215-f. The density of the material falls from 40lbs/cu ft to values of usually between 1 ~ 2lbs/cu ft. During the process of pre-expansion the raw materials hard beads turns into cellular (foam) plastic beads with small closed cells that hold air in their interior. 2nd stage   INTERMEDIATE MATURING AND STABILIZATION: On cooling, the recently expanded particles form a vacuum in their interior and this must be compensated for by air diffusion. This is how the beads achieve greater mechanical elasticity and improve expansion capacity, something very useful in the following transformation stage. This process is carried out during the materials intermediate maturing in aerated silos or mesh bags. The beads are dried at the same time. 3rd stage   EXPANSION AND FINAL MOLDING: During this stage the stabilized pre-expanded beads are transported to molds where they are again subjected to steam so that the beads bind together. In this way large blocks are obtained block molding   (that are later sectioned to the required shape like boards, panels, cylinders etc. ) or products in their final finished shape shape molding. Execution of moulds and casting alloy The basic steps to the process include: A foam pattern and gating system are made using a foam molding press * The foam pattern and the gating system are glued together to form a cluster of patterns * The cluster is coated with a permeable refractory coating and dried unde r controlled conditions * The dried, coated cluster is invested in a foundry flask with loose, unbonded sand that is vibrated to provide tight compaction * The molten metal is poured on to the top of the gating system which directs the metal throughout the cluster and replaces the foam gating and patterns * The remaining operations such as, shakeout, cut-off, grinding, heat treat, etc. are straightforward and similar to other casting processes. The series and major steps in lost foam casting (LFC) What metals can be poured in the Lost Foam process? Generally, all ferrous and non-ferrous materials can be successfully cast using the Lost Foam process. Because the foam pattern and gating system must be decomposed to produce a casting, metal pouring temperatures above 1000 °F are usually required. Lower temperature metals can be poured, but part size is limited. In addition, very low carbon ferrous castings will require special processing. What size range of parts can be produced by the Lost Foam process? Lost Foam castings can be produced in most all metals from a fraction of a pound up to thousands of pounds. Slightly more advanced techniques are used for very large castings. What type of tooling is required and at what cost? Typically, tooling is composed of a split-cavity machined aluminum die that is the negative mold from which the foam pattern is produced. The tooling is highly specialized and must be constructed by experienced tooling manufacturers familiar with the requirements of the foam molders and foundries. Most tooling for Lost Foam patterns will compare favorably with permanent and die cast tooling. Prototype and simple tools may be in the $3000-5000 range while high-end tooling for complex or very large parts can be in the several hundred thousand dollar range. As a result of the materials used and the process stresses, Lost Foam tools can be expected to have 3 to 4 times the cycle life of permanent mold or die casting tools. What lead times can be expected when ordering a Lost Foam casting? As with all processes, lead times vary greatly depending on part complexity. Generally, 8 to 16 weeks is typical for completed tooling and first castings produced. After casting approval, 6 to 12 weeks is typical for production run startup. Rapid prototyping methods can produce castings in as little as 2 to 3 weeks. What size range of parts can be produced by the Lost Foam process? Lost Foam castings can be produced in most all metals from a fraction of a pound up to thousands of pounds. Slightly more advanced echniques are used for very large castings. What is the cost of using the Lost Foam process? Lost Foam castings are generally more expensive than forged parts, or parts made by other casting processes. The value inherent in the Lost Foam process v ersus other processes is seen in tighter tolerances, weight reduction and as-cast features which all results in less machining and cleanup time. Many castings that require milling, turning, drilling and grinding can be made in the Lost Foam process with only . 020† . 030† of machine stock. It is imperative that the features to be cast are discussed by all parties to determine the net finished product cost. What quantities need to be made to make the Lost Foam process practical? The answer, simply, is not as many as you would think. Tooling amortization is a key factor in this determination. Potential overall savings for your application will aid in your decision. Generally, 500-1000 pieces per year is the minimum production run to be economical. Prototyping runs, however, may be as few as 3-5 pieces for Fabricated Foam patterns or 20-100 pieces for Quick-Cut CNC machined aluminum tooling. Application Lost foam casting  is used mostly for automotive applications. Cast iron, aluminum alloys, steels, nickel and in some cases stainless steel and copper alloys are cast in this process. The flexibility of LFC is useful in making complicated casting assemblies for automotive and other metal cast like cylinder heads, weldments, pump housing, Manifolds for automobile, machine bases, automobiles of product produce from lost foam casting glmmarine. com/ManifoldArticle. html Superior Marine Manifolds Agricultural Equipment Part / Farm Machinery Part Product Description Detail Feature: Product Name: Agricultural equipment part / Farm machinery part   Materials: Grey iron, Ductile Iron, High Chrome iron, resistent ironcarbon steels, alloy steels, stainless steels, High Manganese steel   Items: FOB NingBo or Shanghai Place of Origin: Ningbo, China Software for specification drawings: PDF, Auto CAD, Solid work, JPG, ProE   Main production equipments: Wax injection, CNC-machine, machine-center, Heat treatment Furnace lost foam casting for yacht gas piping Specifications 1). lost foam casting 2). reliable product quality 3). on time delivery 4). excellent after-sale service 5). 3D design It is designed for the yacht or the ships gas exhaust piping. Materials: pig iron 250 Surface treatment: galvanizing, and spray-paint Weight: 19. 5 KG Color: black Process: lost foam casting Dimensions:360mm*167mm*102mm Certificate: ISO9001:2000 Advantages * Foam is to carve glue and manipulate Can be used for precision castings of ferrous and non-ferrous metals of any size. * Fewer steps are involved in lost foam casting compared to sand casting. * Core making is eliminated. * Binders or other additives and related mixing processes are eliminated. * High dimensional accuracy can be achieved and thin sections can be cast (i. e. 3 mm). * There is lower capital investment. * The flasks used are less expensive and easier to use because they are in one piece. * The need for skilled labor is reduced. * Multiple castings can be combined in one mould to increase pouring efficiency. * Lower operating costs can be achieved for appropriate castings. Complex castings, particularly internal sections, which require high dimensional accuracy and have thin sections, can be produced very cost effectively in comparison with to conventional sand moulding processes. * Fettling and machining is minimized due to high dimensional accuracy and the absence of parting lines or core fins. * The shakeout process is simplified and does not require the heavy machinery required for bonded sand systems. * High levels of sand reuse are possible. As little as 1-2% of the sand is lost as a result of spills. Periodically a portion of sand may need to be removed or reclaimed to avoid the build-up of styrene. * Complex components can be formed where other casting processes would require multiple components to be assembled. Excellent dimensional tolerances for precision casting. * Lower production cost than traditional Green Sand casting. * Castings can be made from 1 pound up to thousands of pounds with no size limitations. * Lost Foam is an environmental ly friendly process. * The sand is un-bonded and can be recovered and re-used at a low cost. * There is lower capital investment. Disadvantages * pattern costs can be high for low volume application * patterns are easily damaged or distorted due to their low strength. If a die is used to create the patterns there is a large initial cost * The pattern coating process is time-consuming, and pattern handling requires great care. Good process control is required as a scrapped casting means replacement not only of the mold but the pattern as well. What type of tooling is required and at what cost? Typically, tooling is composed of a split-cavity machined aluminum die that is the negative mold from which the foam pattern is produced. The tooling is highly specialized and must be constructed by experienced tooling manufacturers familiar with the requirements of the foam molders and foundries. Most tooling for Lost Foam patterns will compare favorably with permanent and die cast tooling. Pr ototype and simple tools may be in the $3000-5000 range while high-end tooling for complex or very large parts can be in the several hundred thousand dollar range. As a result of the materials used and the process stresses, Lost Foam tools can be expected to have 3 to 4 times the cycle life of permanent mold or die casting tools. What â€Å"as-cast† tolerances can be expected? Typically, a linear tolerance of +/-. 005 inches/inch is standard for the Lost Foam process. This tolerance will vary depending on part size, complexity and geometry. Subsequent straightening or coining procedures will often enable even tighter tolerances to be held on critical dimensions. A targeted effort between the foam pattern producer, the casting producer and the casting user will often result in a Lost Foam casting that substantially reduces or completely eliminates previous machining requirements. Diameter Tolerance 0-1 in. [ or -]0. 007 in. 1-3 in. [ or -]0. 15 in. 3-6 in. [ or -]0. 025 in. In the case of diameters split by glue lines, 0. 005-0. 010 in. should be added dependent on foam size. Linear Tolerance 0-2 in. [ or -]0. 005-0. 10 in. 2-5 in. [ or - ]0. 010-0. 20 in. 0-5 in. with glue lines [ or -]0. 025-0. 035 in. Flatness Tolerance Area 3 x 3 in. [ or -]0. 007 in. Area 10 x 10 in. [ or -]0. 015-0. 020 in. More than 10 in. [ or -]0. 030-0. 050 in. Flatness can be affected by the foam, foam geometry, molding cycle control and foam removal. True Position Tolerance 0-2 in. 0. 025 in. 2-4 in. 0. 030 in. 4-10 in. 0. 030-0. 60 in. 10 in. 0. 080 in. Limitations 1. For low volume applications, the pattern costs are relatively high, therefore in order to increase the substantial economic benefits and decrease the pattern costs, only bulk quantities should be produced. 2. Due to their low strength, the patterns are very easily damaged and/or distorted. 3. There is a very high initial cost if a die is used to create the patterns. 4. The coating process is very time consuming as the pattern handling requires great care. Design considerations: Ensure that there is adequate material: Insufficient material usually leads to incomplete castings in the manufacturing of parts. It is important to calculate the volume of all areas f the casting while also accounting for shrinkage. Consider the Superheat: Superheat is the temperature difference between the metal at pouring and freezing. An increase in the superheat can increase the fluidity of the material for the casting, which can assist with its flow into the mold. Insulate Risers: The riser should be the last to solidify because it is the reservoir of molten material for the casting. Therefore insulating the top will greatly reduce cooling in the risers from the steep temperature gradient between the liquid metal of the casting, and the room temperature air. Consider V/A Ratios: V/A ratio represents the volume to surface area ratio. In casting, sections with low volume to surface area will solidify faster than sections with higher volume to surface area. It is therefore important to consider the V/A ratios in order to avoid premature solidification of the casting and the formation of vacancies. Heat Masses: Sections of the casting with low V/A ratios should be located further away from the risers as this will ensure a smooth solidification of the casting. It is important to avoid large heat masses in locations distant to risers. Sections of the Casting: A heavy section should not be fed through a lighter one. In the manufacturing process, the flow of material is very important. Prevent Planes of Weakness: After the solidifications of castings, columnar grain structures pointing toward the center develop in the material. This causes the sharp corners in the casting to develop a plane of weakness. This is prevented by rounding the edges of sharp corners. Reduce Tubulence: Turbulence is bad because it traps gases in the casting material and causes mold erosion. It can be reduced by the design of a gating system that promotes a more laminar flow of the liquid metal. FUTURE EPF can safely be incinerated and will yield only carbon dioxide and water if the procedure is handled correctly, but the trend has been to recycle it wherever possible. EPF can be recycled into  concrete,  egg cartons, office products, foam insulation, and garbage cans. Unfortunately, only one percent of the 11 billion kilograms of EPF thrown away each year is being recycled. The National Polystyrene Recycling Company, which consists of seven major corporations, including Amoco, Dow, and Mobil, plans to increase this to 25 percent by 1995 by focusing on big users of EPF- fast food outlets and college dining establishments. Since the Montreal Protocol of 1988, new research has focused on ways to reduce CFC use, and on developing alternative blowing agents that will not harm the ozone layer. Recent developments include a process that uses pressurized carbon dioxide to produce smaller, more uniform cells. These in turn provide a foam that is stronger and smoother than earlier foams. All this will bring us an uns are U. S. Department of Energy and metal casting industry industries of the future (IOF), University of Alabama-Birmingham and over 30 universities and industry partners. This strategy has significantly improved the use of LFC in the past years. Emphasis is based on universities research with strong industry participation. The direct results of LFC researches are quickly applied by these positioned partner industries and results from the various applications are evaluated and analyzed. 2. Another strategy used is introducing hundreds of students to metal casting industries were they are well trained and becomes more innovative bringing latest technical knowledge and processes. this has tremendously improve state-of-the-heart technology in improving LFC in the past years. 3. Material(s) selection requires a specific type of manufacturing process(s) and different type(s) of casting techniques. The casting materials specific heat as well as that of the mold material will be influential in controlling the thermal gradients in the system. e. g. melts  fluidity and flow. A material high heat of fusion will take longer to solidify and may improve flow characteristics within the casting. 4. Gases being expelled by the material during solidification can be eliminated by a proper venting system in the mold. This can be planned out during the manufacturing design phase of the casting process. WAYS TO IMPROVE LOST FOAM CASTING 1. Development of computational fluid dynamics tool for modeling the blowing and steaming of expandable polystyrene (EPS) pattern for lost foam casting(mathematical tool). it allows analytical approach to systematically design EPS pattern molds that produces higher quality pattern with reduced lead-time and expense. arena-flow. com 2. Reduction of porosity and fold defects has improve production efficiency, mechanical properties and marketability of lost foam casting. 3. The combination of LFC with 3DP (three dimensional printing) to eliminate machining of mold contours and manual process of drilling and finishing steam holes, i. e. repeatedly printing thin layers of bonding materials on a thin layer of powder to build up a tool(mould) shape from computer-aided design(CAD) 4. Complex and detailed passages and other features are cast directly e. g. oil galleries, crank case ventilation channels, oil drain back passage, coolant passage etc are cast directly into cylinder blocks 5. The use of Flow Particle Image Analyzer to analyzed the wet slurry (prior to its application on the foam pattern) by measuring ceramic particle size and shape. 6. Single and multiple air gauge developed for rapid determination of pattern dimension 7. Compaction gauges were developed to measure sand density in cavities during pattern compaction 8. Distortion gauge to determine when and under what conditions pattern distortion occurs during compaction 9. Developed procedures to measure liquid absorption characteristics of liquid pattern pyrolisis 10. Developed instruments to measure gas permeability 11. X-ray radiography was developed to measure time of fill and also to inspect casting qualities and defects in LFC. Material selection is another way to improve the capability for example: * Certain materials react, (particularly in a molten state), a certain way with other materials they may encounter during the casting process. This should always be a consideration. For example liquid aluminum will react readily with iron. Iron ladles and surfaces contacting the molten aluminum can be covered with a spray-on ceramic coating to prevent this. * When selecting a specific type of manufacturing process, remember that certain materials are more applicable to different types of casting techniques than others. * The casting materials specific heat will as well as that of the mold material will be influential in controlling the thermal gradients in the system. Different materials will factor heavily on the melts  fluidity * A material high heat of fusion will take longer to solidify and may improve flow characteristics within the casting * When manufacturing a casting an alloy that freezes over a tempe rature range problems may occur due to the solid phase interfering with the liquid phase -both of which will be present within the temperature range. To help reduce this problem an alloy with a shorter solidification temperature range may be selected to manufacture the casting with. Or select a mold material with a high thermal conductivity, which could reduce the time spent in this range by increasing the cooling rate. Conclusion using the method of casting by lost foam patterns, we can obtain pieces for industry and ornamental elements / applied art, with complex layouts and different sizes, without the danger of offsetting * using the method of casting by lost foam patterns we can obtain pieces with weights between a few kilograms and tenths of tones, with wall’s width between 1 mm and 50 mm, made of different alloys: ferrous (cast iron and steel) and non ferrous (basic alloys of Al, Cu, Mg); * using the method of casting by lost foam patterns we can obtain pieces with a l ow consumption of materials and energy; * The method of casting by lost foam patterns can be used also for: structural changes and superficial alloying of the pieces; obtaining composite materials with powders insertion and the guidance of hardening by using some active powders, internal coolers or exterior coatings. The gases resulted from the thermal destruction of the polystyrene are toxic for the human being and can generate negative effects on the environment, aspect which imposes the obligation of maintaining under control both the evacuation in the working environment as well as the evacuation in the atmosphere. REFERENCES Design for manufacturability handbook   By James G. Bralla , McGraw-Hill Professional, 1999 Technology ; Engineering Energy research at DOE, was it worth it? : energy efficiency and fossil energy research 1978 to 2000, National Academies Press, 2001 Business ; Economics Fundamentals of Modern Manufacturing: Materials, Processes, and Systems  By Mikell P. Groover, John Wiley and Sons, 2010 Technology ; Engineering A textbook of manufacturing technology: (manufacturing processes)   By R. K. Rajput, Firewall Media, 2008 Technology ; Engineering John Campbell, Butterworth-Heinemann, 2003   Technology ; Engineering   technalysis. com/lost_foam_casting. aspx http://civil-engg-world. blogspot. com/2011/02/polystyrene-ps. html achfoam. com/Lost-Foam-Casting-Process. aspx madehow. com/Volume-1/Expanded-Polystyrene-Foam-EPF. html alibaba. com/product-gs/411205184/lost_foam_casting_for_yacht_gas. html? newId=411205184;pn=1;pt=10;t=12;cids= http://nb-pft. en. made-in-china. com/product/HMZxTjlJqEDn/China-Agricultural-Equipment-Part-Farm-Machinery-Part. html nyserda. org/programs/industry/CaseStudies/lost%20foam. pdf

Gram staining lab report Essay Example

Gram staining lab report Essay Example Gram staining lab report Paper Gram staining lab report Paper Gram Staining Lab Introduction Gram staining is a very important technique used in biology labs all over the world. It is a technique used to differentiate types of bacteria using certain physical and chemical characteristics Of their cell walls. Gram positive bacteria (which show up purple after the gram staining process) have a very thick layer of epidemiological where gram negative bacteria (Which show up pink after the gram staining process) have a much thinner layer of epidemiological. One thing to note is that not all bacteria are gram positive or gram negative, some are Nan-reactive o this type of staining. Bacteria that are non-responsive to this technique are known as gram insensitive. Hypothesize that in the cultures used in this lab for gram staining will contain many gram negative and gram positive bacteria. Material and Methods The following things are needed to run a gram staining experiment: 1, Bacterial cultures . Glass slides . Cover slips . Ammonium Oxalate-Crystal Violet stain . Grams Iodine Solution Ethyl Alcohol Seafaring Solution paper towels . Water I (I Bunsen Burner (Lighter will suffice) 11. Microscope I _ Prepare and heat-fix smears. 2. Stain the slides as follows: a. DOD the crystal violet for one minute. B. Pour off excess dye and wash gently in tap water and drain the slide against a paper towel. Expose the smears to Grams iodine for one minute by washing with iodine, then adding more iodine and leaving it on the smear until the minute is over. D. Wash with tap water and drain carefully. (Do not blot. ) e. Wash with 95% alcohol for 30 seconds. F. Wash with tap wat er at the end of the 30 seconds to stop the decentralization. G. Countersink with 0. 25% seafaring for 30 seconds, Drain. H. Wash, drain, blot, and examine under oil. Draw the cells showing morphology, grouping, and relative sizes, Color a few of the cells of each bacterial species to show the Gram reaction. J. Save these slides and the ones from parts B C of this exercise to use at the next lab period. Looking under the microscope after letting the stain set will prove to be quite interesting, Results The gram staining lab was a huge success. Many different types of both gram negative and gram positive bacteria were identified. There were even a few gram insensitive fellows that had some interesting characteristics such as being spiral shaped. : In all there were four different kinds of gram positive bacteria, two notably different types of gram negative bacteria, and only one gram insensitive bacteria. Discussion There were many good specimens that ended up beautifully stained. One of the Odd things noticed about the gram sensitive bacteria is that the gram negative bacteria were gigantic compared to the gram positive bacteria (XX-1 OX larger). One Of the gram positive types Of bacteria in the cultures that were interesting to me were some that came in colonies of four. (Not identified yet but have been working on it.