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Using sand moulds for step-shape casting tests and different silicon percentage of nodular cast iron it was possible to separate structural variations produced during freezing from those occurring at Ac1 transformation temperature. The results show that an increase in silicon content leading to different variation in the matrix structure> leads to a changing mechanical properties of nodular cast irons. Tensile strength and elongation of obtained as-cast nodular cast iron with the composition of 3.9%C, 3.2%Si, 0.5%Mn are maximum of about 524.5N/mm2 and 19.8% accordingly. In the same nodular cast iron, but only with 0.1% Mn the silicon addition first increases after decreases elongation, impact toughness and hardness. But tensile strength changes to the opposite side
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Martin Luther King, Jr.: \I Have a Dream\ I am happy to join with you today in what will go down in history as the greatest demonstration for f reedom in the history of our nation. Five score years ago, a great American, in whose symbolic shadow we stand today, signed the Emancipation Proclamation. This momentous decree came as a great beacon light of hope to millions of Negro slaves who had been seared in the flames
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应用配有能谱仪的场发射扫描电镜分析了A105钢中裂纹处及基体内残余元素Cu、As和Sn以及P含量.应用Thermo-Calc热力学计算软件计算了A105钢的主要析出相以及钢液中P含量随固相质量分数变化关系.应用Gleeble 1500热模拟试验机对A105钢的高温热塑性进行了研究.发现P偏析是该钢产生横裂的主要原因,残余元素Cu、As和Sn在晶界的偏聚加剧了裂纹的形成,矫直温度偏低加速了裂纹的扩展,而裂纹的形成可能与AlN的析出无关,因为析出的AlN很少
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Consumers make choices over bundles of goods. Consumer theory models the way in which these choices are made. A good is simply a product — such as apples or bananas. A good may be specified in terms of time — such as
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采用真空熔炼法, 经急冷和缓冷两种不同冷却条件制备了Te系化合物TeAsGeSi合金粉体.通过X射线衍射分析, 急冷工艺制备粉体呈非晶态, 缓冷工艺制备的粉体呈晶态, 结晶主相为R-3m空间群的As2GeTe4; 差热-热重分析显示, 升温至350℃时缓冷粉体As2GeTe4成分熔融, 400℃时两种粉体均开始快速失重, 为避免制备过程中发生材料熔融及挥发损失, 确定烧结温度不超过340℃.采用真空热压法制备TeAsGeSi合金靶材, 将两种粉体分别升温至340℃, 加压20 MPa, 保温2 h制备出两种靶材, 其中缓冷粉体制备的靶材致密度高, 为5. 46 g·cm-3, 达混合理论密度的99. 5%, 形貌表征显示此靶材表面平整, 孔洞少, 元素分布均匀
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1 . The chara cte ristics of the n euronal cell Wha t would come to your mind as a definition? It is a cell of the brain: that is not correct, it is more widely spread: CNS = brain + spinal cord, SN P, ente ric s ystem. It is an exc itable cell: it is tr ue but this property is s hared with other cells. Muscles: striated musc le, heart. And other cells too such as endocrine cells present an exc itabilit y that is the property to gene rate action
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solar energy as the driving force for this global process (Fig. 1). All living organisms also require a source of nitro￾gen, which is necessary for the synthesis of amino acids, nucleotides, and other compounds. Plants can generally use either ammonia or nitrate as their sole source of ni￾trogen, but vertebrates must obtain nitrogen in the form
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Idiom, as a linguistic phenomenon, can be regarded as the most special part of language, and they are heavily culture￾loaded. Because of those culture differences, idioms become one of the greatest barriers for cross-culture communication
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 I. Denotative Meaning & Associative Meaning  1. Denotative meaning:  (also known as conceptual meaning) is the meaning given in the dictionary and forms the core of the word meaning. It forms the basis for communication as the same word has the same denotative meaning to all the speakers of the same language
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It is term used as a convenient description for all phases of the disease caused by a bacteria called Brucella. Many names have been applied to it as: 1. Malta fever 2. Mediterranean fever. 3. Gibraltar or rock fever 4. Undulant fever
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