用膜电解法处理低浓度SO2吸收液的三室电解槽材料的选择

提出了用膜电解法处理低浓度SO2吸收液的方法，介绍了三室电解槽的设计原理及在电场作用下，电解槽内离子的迁移和电解反应机理，系统地讨论了电解槽组成单元材料（如阳离子交换器）的选择及在H2SO4－NaHSO3-Na2SO3体系中金属阳极的选择等，并进行了试验验证，得到了很好的结果。     

Clarification of a wheat straw‐derived medium with ion‐exchange resins for xylitol crystallization

BACKGROUND: Xylitol bioproduction from lignocellulosic residues comprises hydrolysis of the hemicellulose, detoxification of the hydrolysate, bioconversion of the xylose, and recovery of xylitol from the fermented hydrolysate. There are relatively few reports on xylitol recovery from fermented media. In the present study, ion‐exchange resins were used to clarify a fermented wheat straw hemicellulosic hydrolysate, which was then vacuum‐concentrated and submitted to cooling in the presence of ethanol for xylitol crystallization. RESULTS: Sequential adsorption into two anion‐exchange resins (A‐860S and A‐500PS) promoted considerable reductions in the content of soluble by‐products (up to 97.5%) and in medium coloration (99.5%). Vacuum concentration led to a dark‐colored viscous solution that inhibited xylitol crystallization. This inhibition could be overcome by mixing the concentrated medium with a commercial xylitol solution. Such a strategy led to xylitol crystals with up to 95.9% purity. The crystallization yield (43.5%) was close to that observed when using commercial xylitol solution (51.4%). CONCLUSION: The experimental data demonstrate the feasibility of using ion‐exchange resins followed by cooling in the presence of ethanol as a strategy to promote the fast recovery and purification of xylitol from hemicellulose‐derived fermentation media. Copyright © 2008 Society of Chemical Industry     

Complex formation of montmorillonite clay with polymers. Part 2: The use of montmorillonite clay–vinyl monomer complex as a comonomer in the copolymerization reaction of styrene–acrylonitrile monomers

The bulk copolymerization of styrene–acrylonitrile monomers using styrene‐N⁺–montmorillonite complex as a comonomer in the polymerization was studied. The X‐ray diffraction (XRD) analysis showed that part of the styrene‐N⁺–montmorillonite complex remained non‐dispersed (immiscible) and the copolymer was excluded from the interlayer of the immiscible part of the clay. The successive chemical extraction process revealed that a reasonable amount of the styrene–acrylonitrile copolymer was directly attached to the styrene‐N⁺–montmorillonite complex and enveloped the clay. Highly exfoliated clay lamella and nanospheres (3–5 nm) were observed by transmission electron microscopy (TEM). The montmorillonite clay assume two different morphologies, immiscible and exfoliated, on the basis of the XRD and TEM data. A simple method of calculation of the ratio of the exfoliated/immiscible amounts of the clay indicated that the amount of the styrene‐N⁺–montmorillonite complex exfoliated into separate lamella was 40 % (w/w) of the amount of the clay samples containing 2 % of the (styrene‐N⁺–montmorillonite complex) clay. This amount of exfoliated clay decreases with the increase of the concentration of the clay. The presence of the styrene‐N⁺–montmorillonite clay in the copolymerization reaction had a minor effect on both the copolymer composition and the molecular weight. Modification of the clay with the derivatized styrene monomer can achieve a nanocomposite using a percentage no more than 4 % (w/w) of complex in the copolymer. Copyright © 2004 Society of Chemical Industry     

过氧化甲乙酮合成研究

论述了过氧化甲乙酮的合成方法，用阳离子交换树脂催化剂代替传统的无机酸催化剂。考察了离子交换树脂用量、反应温度对反应产率、活性氧含量的影响及溶剂对产品稳定性的影响。     

Interval based MINLP superstructure synthesis of mass exchange networks

A new simultaneous synthesis approach for mass exchange networks (MENs) is presented. The technique is adapted from the interval based mixed integer non-linear program (MINLP) superstructure (IBMS) synthesis of heat exchanger networks (HENs). The superstructure interval boundary compositions are defined by the supply and target compositions of either the rich or lean set of streams. Each rich and lean stream in the superstructure has the potential of exchanging mass with streams of opposite kind in each interval based on mass transfer feasibility. The model harnesses the strengths of the stagewise superstructure and the pinch technology methods for mass exchange network synthesis (MENS). The IBMS approach simultaneously trades-off the capital and operating costs for MENs. The superstructure composition interval defining approach introduced in this paper enforces the mixing of split streams at equal compositions, hence there is no need to include mixing equations in the model. Fixing the interval boundaries helps to eliminate the complexities involved in initialisations, thus the region of search for the optimum solution is reduced. The IBMS model is applied to MENS problems involving continuous contact and staged columns. It is also extended to problems involving multiple mass separating agents (MSAs) and regeneration. The results obtained compare well with those in the literature.     

3G认证和密钥分配协议的形式化分析及改进

介绍了第三代移动通信系统所采用的认证和密钥分配(AKA)协议,网络归属位置寄存器/访问位置寄存器(HLR/VLR)对用户UE(用户设备)的认证过程和用户UE对网络HLR/VLR的认证过程分别采用了两种不同的认证方式,前者采用基于"询问-应答"式的认证过程,后者采用基于"知识证明"式的认证过程.使用BAN形式化逻辑分析方法分别对这两种认证过程进行了分析,指出在假定HLR与VLR之间系统安全的前提下,基于"知识证明"式的认证过程仍然存在安全漏洞.3GPP采取基于顺序号的补充措施;同时,文中指出了另一种改进方案.     

基于B/S模式矿山管理信息系统构建技术研究

在全面分析以往矿山管理信息特点的基础上，提出了基于B／S模式开发矿山信息系统的思路。对基于B／S模式开发矿山信息系统的关键技术及开发步骤进行了详细的介绍。     

油气井智能电子防盗阀门

为了有效扼制油田油井原油被盗的现象，减少因被盗及破坏带来的经济损失，研制出GMS3000油气井智能电子防盗阀门。该电子防盗阀门采用了新颖的防盗控制电路和精密的机械联动机构，通过计算机和管理软件得到相应的阀门授权控制，测量结果自动记录、控制阀门的编号和阀门的联动方式，并给予相应的显示。具有可靠、安全、便捷的特点。应用效果表明，达到了油井防盗、防破坏的目的，收到了良好的使用效果，为油田生产安全和提高经济效益提供了可靠的保障。     

渗析法处理酸洗废液的膜面积

本文介绍了渗析地处理钢铁酸洗废液的原理，建立了计算渗析膜面积的公式，提出了渗析适宜条件是流入倍数为１．０５－１．２５，回收率为８０％－９０％。     

虚拟企业图纸数据传输

图纸数据是企业间合作需交换的一种重要的信息。本文分析了虚拟企业环境下企业之间交换图纸数据的要求，提出了一种具体的解决方案，并给出实例。