高温和低张应力引起的非平衡晶界偏聚动力学(Ⅱ)--实验结果的动力学模拟

以文献[1]建立的张应力引起的非平衡晶界偏聚动力学方程模拟了Shinoda T等的磷在钢中的应力时效实验结果和Misra R D K的硫在钢中的应力时效实验结果，模拟结果与实验结果互相吻合。通过模拟发现，张应力使磷-空位复合体以及硫-空位复合体在钢中的扩散系数均增加3个数量级，且磷原子和硫原子的扩散系数分别降低3个和5个数量级。     

Protein Extraction from Heat-stabilized Defatted Rice Bran: II. The Role of Amylase, Celluclast, and Viscozyme

ABSTRACT: The effectiveness of 3 carbohydrases for protein extraction from heat-stabilized defatted rice bran (HDRB) was evaluated. Amylase, viscozyme and celluclast extracted a maximum of 45.4, 12.1, and 28.5% protein, respectively. Further study showed that extracted protein ranged from 9.5 to 58.4% under conditions of water to bran ratio (5:1 to 20:1), α-amylase (0 to 110000 units/10 g rice bran), temperature (35 to 55 °C), and time (1 to 8 h). The maximum protein extracted was 58.4% with a water to bran ratio of 17:1, 87637 units amylase, and 50.9 °C. These results suggest that impure food-grade amylase containing protease is more effective than celluclast and viscozyme in protein extraction from HDRB.     

A three‐dimensional model describing stress‐temperature induced solid phase transformations: solution algorithm and boundary value problems

An always increasing knowledge on material properties as well as a progressively more sophisticated production technology make shape memory alloys (SMA) extremely interesting for the industrial world. At the same time, SMA devices are typically characterized by complex multi‐axial stress states as well as non‐homogeneous and non‐isothermal conditions both in space and time. This aspect suggests the finite element method as a useful tool to help and improve application design and realization. With this aim, we focus on a three‐dimensional macroscopic thermo‐mechanical model able to reproduce the most significant SMA features (Int. J. Numer. Methods Eng. 2002; 55 : 1255–1264), proposing a simple modification of such a model. However, the suggested modification allows the development of a time‐discrete solution algorithm, which is more effective and robust than the one previously discussed in the literature. We verify the computational tool ability to simulate realistic mechanical boundary value problems with prescribed temperature dependence, studying three SMA applications: a spring actuator, a self‐expanding stent, a coupling device for vacuum tightness. The effectiveness of the model to solve thermo‐mechanical coupled problems will be discussed in a forthcoming work. Copyright © 2004 John Wiley & Sons, Ltd.     

芳烃抽提装置技术改造

由于中国石化锦西石化分公司600kt／a连续重整装置的建设，芳烃抽提装置的原料由原来的脱戊烷油变为Ce组分。为此，对抽余油水洗塔和芳烃分离部分的苯塔塔盘，以及苯塔塔顶和塔底抽出部分进行了改造，更换部分机泵和增加变频泵，并将常规仪表改为DCS控制。改造后装置实现一次开车成功，生产出合格产品。抽余油中总芳烃含量小于0．1％，苯回收率达到99%以上。     

Low-cycle fatigue properties of eutectic solders at high temperatures

This paper details the deformation mechanism and low‐cycle fatigue life of eutectic solder alloys at high temperature (around 0.8T_m). Grain boundary sliding generally nucleates a wedge‐type cavity that reduces the low‐cycle fatigue life of metals. In this study, grain boundary sliding has promoted intergranular failure contributing to the reduction in fatigue life of Sn–Ag–Cu alloy. However, grain boundary sliding has exerted no deleterious effects on fatigue resistance of eutectic Pb–Sn and Bi–Sn alloys. The phase boundary sliding with very fine microstructure induces exceptional ductility in these alloys leading to superior low‐cycle fatigue endurance for theses eutectic Pb–Sn and Bi–Sn alloys.     

石油渣油制备针状焦研究--中间馏分热反应研究

石油渣油的组成复杂,分子量分布宽,直接焦化不能生产针状焦。采用一定的预处理技术将渣油中适宜制备针状焦的组分保留,可获得理想的焦化原料。通过以辽河减压渣油为原料,经溶剂萃取对渣油进行"掐头去尾"处理,获得了分子量分布窄、杂质含量少的中间馏分A及馏分B。对馏分A、B分别进行热反应研究,结果表明:渣油的预处理效果明显,中间馏分热反应产物具有光学各向异性物含量高、取向性好等特点,是制备针状焦的理想原料。     

金的分离富集

综述了金的分离和富集方法，主要包括各种吸附和萃取方法。采用活性炭和泡沫塑料(简称泡塑)吸附分离金是传统的分离富集法，有负载活性炭和有负载泡塑可以提高富集金的能力。近些年，离子交换树脂和离子交换纤维素在分离富集金的应用中，占有相当大的比例。萃取法除了使用传统的MIBK作为萃取剂，又见报道硫醚、亚砜、醇类等作为萃取剂的各种萃取体系。中引用参考献107篇。     

Beyond Boundary Objects: Collaborative Reuse in Aircraft Technical Support

Boundary objects are a critical, but understudied, theoretical construct in CSCW. Through a field study of aircraft technical support, we examined the role of boundary objects in the practical achievement of safety by service engineers. Their resolution of repair requests was preserved in the organization’s memory via three compound boundary objects. These crystallizations did not manifest a static interpretation, but instead were continually reinterpreted in light of meta-negotiations. This suggests design implications for organizational memory systems which can more fluidly represent the meta-negotiations surrounding boundary objects.     

矿石中金的快速测定

研究了活性炭纤维滤布富集分离的条件和解脱方法,并利用微波溶样、液珠萃取比色法测定矿石中的金。该方法的测定范围为(0.5~xx)×10-6,相对标准偏差RSD为3.2%,可用于矿石中金的野外快速测定。     

EXPERIMENTAL STUDIES AND NUMERICAL CALCULATION ON TURBULENT BOUNDARY LAYER OF WATER FLOW ALONG CURVED SURFACE

This paper will introduce experimental studies and numerical calculation onturbulent boundary layer of water flow along curved surface in our country in recent years.Onthe basis of the experimental studies,the effects of curvature and roughness on velocitydistribution and pressure distribution and the change of turbulent flow boundary layer onoverflow bucket concave surface is discussed.We proposed the empirical formula of velocity,pressure and the change of turbulent flow boundary layer on outlet bucket concave.According tothe momentum principle,we have deduced the momentum integral equation full water depthboundary layer and using the element as control unit inside the boundary layer on concavesurface of bucket.Combining with continuity equation,we have computed the boundary layerdevelopment on the bucket of a spillway.Compared with the field experimental data,thecalculation results are available.Under polar coordinates,a mathematical model for simulatingtime-averaged flow characteristics in concave surface of bucket is established.The turbulent flowfield on concave surface of bucket is calculated by SIMPLE method and this mathematicalmodel.The flow velocity field,pressure field,distribution of turbulent kinetic energy,distribution of turbulent energy dissipating rate and distribution of shear stress are available.Thecalculation value is consistent with measured test data.