Analysis on Refining the ZLD11 Nuclear

The ZLD11 alloys containing Sr have been prepared by adding AlSr master alloy and the refinement effect of Sr on the microstructure are investigated with different contents of Sr in the finish alloys such as 0.04%,0.06%,0.08%and 0.10% Sr to change the grain size of ZLD11 alloy in mass, both microstouctve observation and gain size statistical analysis have been used to discover the proper additions of Sr. The effects of the main alloying elements on properties of ZLD11 alloy, as well as the smelting process are introduced. The results indicate that AlSr master alloy as a crystal refiner with X metal mold casting process has an effective grain refinement for ZLD11 alloy, the best refinement effect were obtained with addition of 0.08% Sr.     

Micromodel of Computer Emulational Simulation on Twin-roll Casting Strip Solidification Structure

Based on the research on the solidifiation of twin-roll casting strip,the analytical model and emulational model of nucleation,the growth of dendrity tip and colunar dendrity transformation to equiaxis dendrity (CET)of twin-roll casting strip solidification are established by means of the principle of metal solidification and modern computer emulational technology.The foundation for the emulational simulation of twin-roll casting strip solidification structure is laid.     

亚麻籽油精炼过程中HACCP安全体系的构建

HACCP体系是食品生产企业实现产品安全的管理体系。针对亚麻油精炼的生产工艺进行了危害分析,确定5个关键控制点,并详细制定HACCP计划,将危害因素降到最低限度,确保亚麻籽油生产的质量安全,为油脂生产企业HACCP安全体系的构建提供参考模型。     

Effect of Mischmetal Additions on the Ignition Temperature ofMolten ZM5 Magnesium Alloy

Magnesium alloy is prone to burning during its melting and casting in air, which is a major factor in obstructing its application. Fluxes and cover gases are currently used for the melting and production processes, and semi solid thixocasting is also used to lower the operation temperature, but there still remain many problems. Alloying is a promising method of preventing Mg from burning. The effect of mischmetal additions on the ignition temperature of ZM5 Mg alloy was investigated and compared with that of pure rare earths. It is shown that an addition of 0.12 % mischmetal can greatly heighten the ignition point and such an alloy can be widely applied.     

Modification Effects of La-Rich Mischmetal and Strontium Metal on A357 Alloy

Opting for desirable modifiers is an important way to obtain coast Al-Si-Mg alloys with both high strength and good toughness properties.Structures,mechanical properties and hydroden contents of as-cast and as-heattreated A357 alloy are investigated by comparing modification effections of lanthanum(La)-rich mischmetal and Strontium (Sr).It is shown from our experiments that modification effections of La-rich mischmetal is better than that of Sr as Fe content in the alloy is lower than 0.11% in the aspects of removal of hydrogen from the alloy,refinement of entectic silicons and improvement of mechanical properties,therefore,La-rich mischmetal is a desirable modifier for Al-Si-Mg alloy.     

Forecasting of the Sr Modification Effects on Al-11.7%Si Alloy

The freezing curve of the Sr modificated Al-11.7%Si eutectic alloy is obtained by experiment,and the solid phase grow speed curve is calculated.The results show parameter that the maximum of solid phase grow speed is an effective parameter for describing Al-Si alloy modification,and the accurate forecasting on modification result can be realized by computer test. [WT5HZ]     

Effect of Chemical Composition on Formation Performance of 7050 Alloy Billets

The casting technology of 7050 alloy bilits is researched. that are used to produce slabs for air materials.Because the composition of 7050 alloy is very complex,the Cu and Zn elements contents are higher and Fe and Si impurity elements contents are controlled lower, at the same time ,the specification and the width-thickness ratio are large ,all of above result the tremendous crack trend when casting and bad casting formation performance . The formation performance of 7050 alloy has been improved and qualified billits are obtained by optimizing the composition of 7050 alloy, including raising Fe/Si ratio and Zn/Mg ratio ,reducing Cu content and adopting the joint refinement with block and silk shaped Al-5Ti-1B.     

Review on the Research of High-strength Wrought Magnesium Alloy ZK60

ZK60 magnesium alloy is one of high-strength wrought magnesium alloys. Owing to its high strength and low density, it has nearly the highest strength to density ratio among existing materials. Because its strength approximates to high-strength aluminum alloy 7075, it has promising application future. The history of magnesium alloy ZK60 and researches on its microstructure, mechanical properties, surface treatment, and the effects of alloy elements and microelements are reviewed . Further more, the authors put forward methods to improve its microstructure and mechanical properties and prospected the development future of this alloy in the aspects of surface treatment and application.     

不同预处理对萝卜花药组织结构的影响

研究了花枝低温预处理及常、低温下离体花药的甘露醇和秋水仙素预处理对萝卜花药组织结构的影响。结果表明:4℃低温条件下处理枝条,处理1,3,5 d的花药绒毡层细胞出现从排列整齐到逐步退化的现象,药室中的小孢子染色也逐渐加深,7 d后花药壁细胞退化严重,小孢子数目则减少,故枝条低温预处理合适的时间为3~5 d。4℃条件下离体花药经甘露醇和秋水仙素预处理3 d后,药室中小孢子数目多,染色深,处理超过3 d,小孢子数目急剧减少,活力下降。25℃条件下甘露醇和秋水仙素预处理不利于花药结构的维持与小孢子活力的保持。     

温度对棉纤维超分子结构的影响

全铃期日均温19.5℃和夜均温17.0℃以上时α角随铃龄增大不断宽化(变大),低于该范围时α角随纤维发育不断变小(优化).角和ψ角随纤维发育不断优化(变小),不同处理相同铃龄随温度降低ψ角与ψ角值有变大趋势.α、ψ及ψ角值与铃龄呈曲线关系,且相关显著.随纤维发育横向晶粒尺寸逐渐增大,相同铃龄随温度下降晶粒尺寸值降低,横向晶粒尺寸值与铃龄及全铃期日均温呈曲线关系,且相关显著.     

Dynamic Control Model for the Secondary Cooling of Slab Casting Based on Neural Networks

A dynamic control model for the secondary cooling of slab casting is presented to reduce the difference between the actual temperature and the goal surface temperature of slab. The model, which is based on the BP neural networks for forecasting the temperature and the fuzzy neural networks for dynamically controlling the water in the secondary cooling in the continuous casting, could timely adjust and allocate the water according to the speed and temperature of slab. A series of tests have been conducted based on inputs of the No. 2 slab caster in a steel plant. It has been shown that the model, which integrate the charateristics of water controlling problem in secondary cooling into the temperature status of slab during the cooling process, can control the water in secondary cooling efficiently and dynamically according to the situation of actual production.     

Effect of Yttrium on Morphologies of Precipitation Phases Along Grain Boundary of As-cast ZK60 Magnesium Alloy

Morphologies of precipitation phases along grain boundary of the as-cast Mg-6.0Zn-0.45Zr, Mg-6.0Zn-(1.2Y) and Mg-6.0Zn-0.6Zr-1.0Y alloys are studied by using the methodologies of metallurgical phase analysis, scanning electron microscopy(SEM) analysis and energy diffraction x-ray(EDX) analysis. The experimental result indicates that the main precipitation phases along grain boundary of the as-cast alloys Mg-6.0Zn-0.45Zr is Mg-Zn binary phase. There are two kinds of precipitation phases along grain boundary for Mg-6.0Zn-1.2Y and Mg-6.0Zn-(0.6)Zr-1.0Y alloys. One grew at triangular grain boundary, which is fish-bone -like and contained Mg-Zn binary phase and Mg-Zn-Y ternary phase. The other distributed mainly around the grain, which is net-like and contained Mg-Zn-Y ternary phase. In addition, there are lots of granular phases, extending to the interior of the grain, at the rim of grain boundary phases. Finally, Y can intensively change morphology of precipitation phases along grain boundary of the as-cast Mg-Zn-Zr alloy (ZK60) alloys.     

Reserach on the Die Forging CAD System of Long Shaft Type Forgings

This paper,by using AutoCAD Advanced Modeling Extension(AME),solvesthe difficulty of three-dimensional solid object modeling of forging die CAD on a porsonal computer,sets up the die forging CAD system(DFCAD system)of long shaft type forgings. It is convenient todesign die forging processes and forging dies , and can get 3-D and 2-D forging die drawings.     

不同遮光程度对玉米叶片结构的影响

为了研究玉米多样性种植增产、抗病的可能机制,以不同遮光处理玉米植株时玉米叶片为实验材料,用光学显微镜对玉米叶片表皮细胞密度、表皮细胞长宽及大小、上、下表皮厚度和叶片厚度进行测量研究。结果表明,玉米叶片表皮细胞密度、上表皮厚度、下表皮厚度和叶片厚度的变化趋势为：未遮光处理时（对照）的最大,其次是遮光后透光率为30%,而透光率为10%时的最小。玉米叶片表皮细胞长度、宽度和面积以透光率10%时最大,透光率为30%的次之,而未遮光处理的最小。由此看出,随着透光率的增加,上、下表皮厚度和叶片厚度显著增加,由于植物病原真菌侵染时是通过直接穿透植物叶片表皮实现的,因此叶片的这种解剖结构变化可能是作物影响病菌侵染过程,减轻病害发生程度的机制之一。同时还观察到表皮细胞长度、宽度和单个表皮细胞面积均显著减少,而表皮细胞密度增加,从而导致单位叶面积的细胞数目增多,细胞总表面积增加,光合膜面积增大,有利于叶片整体光合效率的提高。     

新疆产业结构演进对城市化的动态影响研究

为了更好的了解新疆现阶段的产业结构演化过程对新疆城镇化进程的影响,以新疆1985—2013年的新疆三次产业产值为数据源,运用卡尔曼滤波算法,构建了状态空间变参数计量经济模型。研究结果表明：第一产业对新疆的城市化进程有负效应影响;第二产业是促进新疆城市化进程的主要动力,正处于迅速发展的重要时期;第三产业对新疆城市化由稳定的正效应影响转变为持续下降的负效应影响。新疆第二产业和第三产业对城市化发展的影响之间有显著的相反发展趋势,分析认为新疆的城市化发展过于依赖第二产业,应合理调整和安排产业结构与政策导向,提高第三产业生产水平,这对促进新疆城市化进程,城市工业化等方面具有重要意义。