三元催化转化器中的现象分析与研究

在介绍和分析国内外研究现状的基础上，论述了三元催化转化器中的传递现象及化学反应动力学．探讨了三元催化转化器在暖机过程中有害物质的催化转化模型，并建议采用数学模型的方法对催化器在发动机所有工况下的工作过程进行模拟。     

Novel blood-compatible waterborne polyurethane using chitosan as an extender

A series of novel block polymers of polyurethane (PU) and chitosan have been prepared in two steps. The first step is the preparation of PU prepolymer, obtained from polytetramethylene oxide glycol (PTMO, M_n = 1000), isophrone diisocyanate (IPDI), and 2,2′-dimethylol propionic acid (DMPA), followed by ionizing PU prepolymer with triethylamine (TEA). The second step involves PU chain-extended by water-soluble chitosan of low molecular weight (M_n = 5000) by self-emulsion polymerization method. The sizes of the latex particles, morphology, and copolymer architecture have been characterized by dynamic light scattering (DLS), general tensile test, infrared spectroscopy (IR), surface contact angle measurement, and transmission electron microscopy (TEM). Furthermore, it shows that the addition of chitosan remarkably increases anticoagulative property of PU elastomers confirmed by the recalcification time. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Modeling dynamic developable meshes by the Hamilton principle

In this paper, a new dynamic developable surface model is proposed. The proposed model represents developable surfaces using triangle meshes. A novel algorithm is proposed to introduce the Hamilton principle into these meshes such that the resulting developable model is dynamic, i.e., it can offer a time-dependent continuous path to deform the model. Applications with examples are presented; these show that the proposed technique can model buckled developable surfaces well, and can offer physically-realistic animations of deformed developable surfaces.     

基于HMS87C1408B的籽棉、菜籽和粮食水分综合测试仪

介绍了使用HMS87C1408B作为主控芯片的籽棉、菜籽和粮食水分综合测试仪的实现方法,重点说明了阻抗变换、软件驱动LCD和语音播报技术的实施.     

Rückgewinnung von Vinylchloridmonomer

The production of the polymer polyvinylchloride (PVC) emits a high amount of waste gas. The recovery of the evaporated base product vinylchoridemonomer (VC) is an important aspect for the economics of the whole process. Membrane and vacuum technology improve the efficiency and the economics of the recovery process considerably.     

激光光束质量因子的研究进展

本文详细分析了各种光场下光束质量M2因子。在不同的场中,A.E.Siegman当初所定义的M2因子,已经有了很大的变化,因而M2因子的特性也与当初不同,不仅M2因子可以大于等于1,而且可以小于1,甚至小于0。其反映的物理意义,也从经典场中的衍射极限倍数,变化为非经典场中的准直性量度以及对空间相干性的某些反映。此外还列举并分析了几种特殊的光束质量因子,最后讨论了M2因子应用的问题并指出了其局限性。     

Oral absorption improvement of poorly soluble drug using solid dispersion technique

A new triazol antifungal agent, (+)-2-(2,4-difluorophenyl)-3-methyl-1-(1H-1, 2,4-triazol-1-yl)-3-[6-(1H-1,2,4-triazol-1-yl)pyridazin++ +-3-ylthio]butan-2-ol (MFB-1041), shows poor oral absorption and is practically insoluble in water (1.2 micrograms/ml). Solid dispersion systems with an enteric polymer such as hydroxypropylmethylcellulose phthalate (HP-55) and carboxymethylethylcellulose (CMEC), and a nonenteric polymer, hydroxypropylmethylcellulose (Metolose) were evaluated to improve drug absorption and solubility. The oral bioavailabilities of these solid dispersions in beagle dogs were over 6 times higher than that of a suspension system with increasing drug solubility in an alkaline medium. X-Ray powder diffraction measurement of the solid dispersion showed a complete drug phase change from a crystal to an amorphous state. Further, from the results of a stability test, the preparations were stable in a desiccated condition and the absorption profiles also showed no change. From the results, it was suggested that the oral administrative preparation of MFB-1041 having a superior absorption profile and a high stability could be obtained by a drug phase change from a crystal to an amorphous state, especially in the spray-drying method using enteric polymers.     

Cyanex有机膦类萃取剂在贵金属溶剂萃取中的研究和应用

介绍了近年来Cyanex有机膦类萃取剂在贵金属溶剂萃取中的研究状况及应用进展，展望了该类萃取剂在贵金属分离提取中的应用前景。     

PTA装置自动控制系统实现安稳运行的对策

针对PTA装置的工艺生产特点，对自动控制系统当中出现的不同种类的问题，进行了多方面的简要探讨与分析，并提出实现安稳运行相应的对策。     

Analysis and design of aperture-coupled microstrip patch antennasand arrays fed by dielectric image line

This paper presents the analysis and design of aperture-coupled microstrip patch antennas and arrays fed by an dielectric image line. A theory based on the cavity model of the microstrip patch antenna and the change in the modal voltage of the image line at the aperture was developed to analyze the single element aperture-coupled microstrip patch antenna. The theory developed was combined with the array theory to design linear traveling wave arrays at X-band and Ka-band frequencies. The required taper in the excitations of the individual patches of the array was achieved by varying the aperture dimensions. Experiments show very good results for the antennas and the arrays