有关肾病调查研究显示，目前我国肾病患者已多达2000万人；尿毒症患者约为100万人，年死亡率为67.6％，占死亡人群率的10％。虽然现代医学肾病治疗以血液透析和肾移植为主要手段，但肾源稀缺、人体排异反应以及费用昂贵等难题却始终困扰着医患双方。因此，如何有效遏止肾病的发展，尤其是对尿毒症患者的早期治疗、晚期减少透析次数，减轻尿毒症并发症，已成为世界医学界的一项重大课题。

中医学理论认为肾病、尿毒症的发生主要是以下三点原因:

一是先天肾精气不足，遗传物质匮乏.

二是后天肾失所养，脾肾劳伤虚损。

三是寒热湿瘀邪毒阻闭，致使脾肾衰败，五脏失和；湿毒内蕴，精亏血虚。

有关肾病专家特别提出，重视肺失宣降、气机闭郁在肾脏病发病、发展中的作用，结合现代医学有关科研成果，深入研究肾病尿毒症治疗的有效方法。灵活运用中西医理论，在大量临床治疗验证、动物实验和毒理学研究的指导下，普遍认为阻断肾病发生的病因——肾脏纤维化，才能从根本上解决肾病尿毒症治疗的难题，并能减少肾病反复发作的次数。通过阻断肾脏纤维化，使得各种肾病和尿毒症引起的反复感冒、尿白尿、顽固性恶心、水肿、血尿、贫血和高血压等症状消除，提高肾病尿毒症患者的生活质量

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The importance of the development of wind energy has indisputable that a large-scale wind energy development must first resolve a series of key scientific issues. The importance of the development of wind energy has indisputable that a large-scale wind energy development must first resolve a series of key scientific issues.

Deputy Director of the National Climate Center, China Meteorological Administration, solar wind energy resource assessment and research fellow at Rayong, director of the Center of Atmospheric Physics, Chinese Academy of Sciences researcher at the Institute of Hu in the non-acceptance of the "Science Times" interview, emphasized the same point of view.

In that case, how wind energy resource development and atmospheric sciences which faces the key scientific problems?
Extreme weather on the impact of wind power development

"In 2003 on the 13th typhoon ‘cuckoo’, in 2006 on the 1st of Typhoon ‘pearl’ and No. 8 typhoon ‘Saomai’ were the result of Shanwei in Guangdong Red Bay wind farm, the South Australian wind farm Cangnan in Zhejiang Province and the Cape mountain-top electric fan of the serious Damage. "Talking about extreme weather and climate on the impact of wind power resources development, Rayong, said that in the past, in the design of wind power, on the impact of extreme weather and climate much about, for example, on the southeast coast of the typhoon, how strong On how much wind power. These issues have now become a wind energy resource development must first resolve the key issues, in particular, have to consider extreme weather or weather disasters, such as the strong sandstorm, strong wind, strong typhoons, ice, lightning, and so on.

Similarly, non-Hu pointed out how extreme weather conditions to guide the construction of wind power and layout of the macro-key areas, the scientific assessment of how different parts of the wind farm construction climate risk (mainly as a result of extreme weather conditions of wind power damage probability) is At present, the development of wind energy to the important scientific issues. For example, tropical cyclones, tornadoes, and the outbreak of the extratropical cyclone, low temperature, storm surge, sea ice, and other adverse weather conditions seriously affected the safety of wind power operation, in which the impact of tropical cyclone is the worst.

Non-Hu, for example, at present, the atmospheric boundary layer of air in a high range of tropical cyclone gas properties is still a lack of in-depth understanding, not for coastal and offshore wind farm designed to provide reliable aerodynamic parameters, wind farm planning and construction of a lack of climate Based on risk analysis.

"In the global climate change, background, only when the scientific understanding of China’s wind energy resources in the past, the causes of change in truth, and possible future changes make more accurate predictions on the basis of wind energy resources in order to achieve China’s largest The scale of sustainable development and utilization of wind power for the distribution of macro-and micro-site to provide a scientific basis. For example, China’s wind energy resources in the past is how to change? Future trends in the evolution of how? Whether the sustainable use? "Hu said non.

Wind resource monitoring and forecasting system

Due to the extensive use of wind energy, wind power more and more enterprises need accurate forecasting service. Wind power business-to-short-term energy demand is forecast: the need for generating capacity, rather than forecasting the forecast wind speed; released a day ahead of schedule 36 to 48 hours by the time forecasting; credibility of the forecasts given; a few days in advance of the medium-term forecast of Planning and management is very important to maintain.

"Today’s weather and climate models are basically not on the scale of wind generators speed distribution to the forecast fine." Non-Hu said that building large-scale wind farm to be built to increase wind power wind power level of short-term forecasting.

Rayong also pointed out that the power grid because of scheduling needs, wind power is estimated that the Internet needs of its generating capacity. In this regard, China’s current wind forecasts are mainly based on local weather conditions to carry out a number of wind power forecasting. In June 2006, the China Meteorological Administration set up solar wind energy resource assessment center. The center has started to do some of the wind power forecasting. "We are two wind farm and co-operation for a number of wind power forecasting system for construction and development."

"But these are far from adequate, the current urgent need for the establishment of specialized services in the wind wind power to deploy the Internet wind resource monitoring and forecasting system." Rayong pointed out.

The establishment of wind energy resource assessment of the refinement of the model

"It’s like the development of mineral resources prospecting first, the development of wind generator  resources must first find out where the wind, but wind energy and mineral resources, is not necessarily able to have the wind on the issue of wind energy." Non-Hu said that the need to establish An effective scientific methods detailed investigation of wind energy resources. These include the improvement of scientific methods and the development of international wind energy resource assessment of the existing theories and methods for the establishment of China in the climate and terrain characteristics of the wind energy resource assessment model of refinement.

From the perspective of atmospheric science, wind turbine is the main advantage of the surface layer of a stroke kinetic energy resources (wind turbine wheel does not generally a high degree of over 120 meters), it is necessary to learn more about Chinese fans in the range of high (120 meters) of the Wind energy resources is the number of total reserves, where China is rich in wind energy resources in the macro area.

Rayong will be introduced to the reporters, in the past, China’s wind energy resource assessment is mainly used in meteorological stations on the 10-meter high degree of conventional pilot and a small amount of wind measuring tower, the spatial distribution of meteorological stations by the density of the wind measurement tower a short sequence data China has not yet been established, as well as adapt to the characteristics of the monsoon climate and terrain characteristics of the fine theories and methods to assess factors such as the restrictions can not be accurately given a high degree of fan on the wind energy resources as well as the total reserves of fine (up to 1 kilometer horizontal resolution, vertical-resolved Rate of 10 meters; with) the distribution of the region. Therefore, in order to achieve China’s large-scale wind energy resources for sustainable development and utilization, we must first learn more about Chinese fans on a high degree of wind energy resources in a specific location.

Rayong further stressed the need to wind energy resources in the macro-rich area of science to guide the micro-site wind power, China needs to establish appropriate characteristics of the monsoon climate and terrain characteristics of the micro-site model of wind power, wind energy resources in order to achieve the precise assessment of , And the results can be better used in wind power in the design and construction.

In order to carry out wind energy resource assessment of the fine, but also for the dynamic design of wind power and wind power forecast to provide technical support, but also the need for wind power and small-scale fan-scale numerical model.

"In short, our aim is to achieve genuine multi-scale simulation of the wind and forecasting, that is what we have to overcome one of the key technical problems." Hu said non.

die casting product series are commonly zincifying microns agaist the fierce outdoor environment.Ductile iron casting and grey iron casting covering Machine tools industries ¡¢ Pumps industries ¡¢ Gas & steam valve industries ¡¢ Automobile industries ¡¢Air compressor industries ¡¢Gear cases & accessories ¡¢ Electric motor body & accessories and so on at the process of Resin Chemically Bonded Sand Cast, Resin Shell Cast, and Green Sand Cast.

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Vanadium has an effect on gray iron similar to molybdenum, but the concentration must be limited to less than 0.15 percent if carbides are to be avoided. Even in such small amounts, vanadium has a beneficial effect on the elevated temperature properties of gray iron.

Steel Casting The beneficial effect of relatively small additions of tin (less than 0.10 percent) on the stability of pearlite in gray iron has been reported by Davis et all. The results of extensive use of tin in automotive engines has been reported by Tache and Cage[12]. Its use is particularly helpful in complex castings wherein some sections cool rather slowly through the Ar3 temperature interval. It has been found that additions of up to 0.05 percent antimony have a similar effect. In larger amounts, these elements tend to reduce the toughness and impact strength of gray iron, and good supervision over their use is necessary.

Aluminum Casting Although most gray irons contain some titanium and the effect of titanium on the mechanical properties has been investigated many times, it is only recently that Sissener and Eriksson[13] have reported the effect of titanium reduced from a titanium containing slag in an electric arc furnace. With titanium contents of 0.15 to 0.20 percent, the graphite flakes tend to occur as Type D graphite rather than predominantly Type A, which is generally considered desirable. They found that for irons with carbon equivalent of less than about 3.9 percent, the addition of titanium tends to lower tensile strength. but, for the higher carbon equivalent irons, tensile strength is improved. Increasing the titanium content of gray iron from about 0.05 to 0.14 percent through the use of a titanium bearing pig iron increased the strength of a hypereutectic iron in an ASTM Specification A 48 test bar A (7/8 in. diameter) from 22,000 to 34,000 psi. Further work is being done with titanium additions.

Stainless Steel Casting Normally. nitrogen is not considered as an alloying element and generally occurs in gray iron as a result of having been in the charge materials. Morrogh[14] has reported that at higher nitrogen levels the graphite flakes become shorter and the strength of the iron is improved. Gray irons usually contain between 20 and 92 ppm (0.002 to 0.008 percent) nitrogen. If the nitrogen approaches or exceeds 100 ppm, unsoundness may be experienced if the titanium content is insufficient to combine with the nitrogen.

The sand used for sand molding is critical and determines the favorable or unfavorable out come of the casting, it controls the tolerances, surface finish and the repeatability while in production. The sand must exhibit the following characteristics:

Characters of sand casting:

FLOWABILITY: The ability to pack tightly around the pattern.

PLASTIC DEFORMATION: Have the ability to deform slightly with out cracking so that the pattern can be withdrawn.

GREEN STRENGTH: Have the ability to support its own weight when stripped from the pattern, and also withstand pressure of molten metal when the mold is cast

PERMEABILITY: This allows the gases and seam to escape from the mold during casing.
All of these requirements are dependent on the amount of active clay present and on the water content of the mixture.

SAND CASTING BENEFITS
Least expensive casting process
Casting can be up to several tons
Less expensive than machining shapes from bar stock
Can cast intricate shapes
Can be used with most pourable metals and alloys

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Grey cast iron also known as flake graphite cast iron, is a type of casting iron in which most of the carbon is present as flake graphite .The propertises of grey cast iron depends on the distribution, sizs and amount of graphite flakes, and the matrix structure. These factorys are in turn, influenced mainly by the manufacturing conditions, chemical composition, solidification time and rate of cooling in he mould. Grey cast iron exhibit low to moderate strength, low modulus of elasticity, low notch sensitiviy, high thermal conductivity, moderate resistance of thermal stock , and outstanding castability.

Ductile iron casting as found wide acceptance and competes favourably with steel such that its use in engineering has increased in recent times as while grey cast iron and malleable cast iron has fallen in popularity as other materials such as plastics have found favour.

Iron Casting is an alloy of iron and carbon in which the carbon is in excess of the amount that can be retained in solid solution in austenite at the eutectic temperature, In addition, silicon, manganese,sulphur and phosphorus are contained in varying amounts.

Iron Casting are a family of ferrous metals with a wide range of properties produced by being cast into shape as opposed by being formed,other elements are used to control specific properties, cast irons have a wide range of mechanical properties which make them suitable for use in engineering components. The wide spread use of cast iron is as a result of its low cost and versatile properties.