绿色电镀技术系统示范项目

根据生产实践和现场数据,详细介绍了安美特公司配合中国环境保护产业协会和中国表面工程协会共同启动的绿色电镀技术示范项目的实施状况。该示范项目的核心内容是包括前处理、锌合金电镀及后处理在内的防腐蚀镀层组合实用技术。经被试点电镀企业投放于大生产实践的长期使用,该示范项目取得了上佳的环境和经济效益:单位水耗降低了85%,单位能耗降低了65%;电镀废水中COD减少了50%,电镀速率提高了50%,产品一次合格率从90%提高到98%;钝化液中锌杂质削减了65%～95%,铁杂质削减了85%～95%,而且彻底杜绝了锌镍合金电镀过程中氰化物的产生。     

尼龙(PA)电镀前处理

介绍了适用于尼龙(PA)基材的新型前处理工艺.经过膨胀、调校、钯活化、还原、化学镍(δ=0.3 μm)、预镀镍或铜(δ=2～5 μm),酸铜(δ=20 μm),光亮镍(δ=12 μm)、装饰铬(δ=0.3μm)等工艺后,可在尼龙表面获得结合力良好的装饰性镀层.该工艺为开发尼龙塑料在电镀业的应用迈出了重要的一步.     

Presence of acetyl coenzyme A (CoA) carboxylase and propionyl-CoA carboxylase in autotrophic Crenarchaeota and indication for operation of a 3-hydroxypropionate cycle in autotrophic carbon fixation

The pathway of autotrophic CO2 fixation was studied in the phototrophic bacterium Chloroflexus aurantiacus and in the aerobic thermoacidophilic archaeon Metallosphaera sedula. In both organisms, none of the key enzymes of the reductive pentose phosphate cycle, the reductive citric acid cycle, and the reductive acetyl coenzyme A (acetyl-CoA) pathway were detectable. However, cells contained the biotin-dependent acetyl-CoA carboxylase and propionyl-CoA carboxylase as well as phosphoenolpyruvate carboxylase. The specific enzyme activities of the carboxylases were high enough to explain the autotrophic growth rate via the 3-hydroxypropionate cycle. Extracts catalyzed the CO2-, MgATP-, and NADPH-dependent conversion of acetyl-CoA to 3-hydroxypropionate via malonyl-CoA and the conversion of this intermediate to succinate via propionyl-CoA. The labelled intermediates were detected in vitro with either 14CO2 or [14C]acetyl-CoA as precursor. These reactions are part of the 3-hydroxypropionate cycle, the autotrophic pathway proposed for C. aurantiacus. The investigation was extended to the autotrophic archaea Sulfolobus metallicus and Acidianus infernus, which showed acetyl-CoA and propionyl-CoA carboxylase activities in extracts of autotrophically grown cells. Acetyl-CoA carboxylase activity is unexpected in archaea since they do not contain fatty acids in their membranes. These aerobic archaea, as well as C. aurantiacus, were screened for biotin-containing proteins by the avidin-peroxidase test. They contained large amounts of a small biotin-carrying protein, which is most likely part of the acetyl-CoA and propionyl-CoA carboxylases. Other archaea reported to use one of the other known autotrophic pathways lacked such small biotin-containing proteins. These findings suggest that the aerobic autotrophic archaea M. sedula, S. metallicus, and A. infernus use a yet-to-be-defined 3-hydroxypropionate cycle for their autotrophic growth. Acetyl-CoA carboxylase and propionyl-CoA carboxylase are proposed to be the main CO2 fixation enzymes, and phosphoenolpyruvate carboxylase may have an anaplerotic function. The results also provide further support for the occurrence of the 3-hydroxypropionate cycle in C. aurantiacus.     

ON TRANSITIVE SOLUTIONS OF $-FUZZY RELATION EQUATIONS DESCRIBING FUZZY SYSTEMS

The set of solutions of the $-fuzzy relation equation over finite spaces with values from linear lattice is considered. It is shown, that there exist solutions with various known types of the fuzzy transitivity, while the maximum solution has a special new type of so-called α-transitivity. An interesting convergence property of natural powers of the maximum solution is presented. That result and analogous ones, which hold for other types of transitive solutions, are applied for the analysis of the convergence of fuzzy systems described by $-fuzzy relation equations. In such a way, a new conceptual model for the behaviour of fuzzy systems is provided.     

The effect of pentaerithrityl-tetranitrate on parameters of the microcirculation

AIM OF THE STUDY: The effect of organic nitrates on microcirculation was first studied in 1964 and with regard to glyceroltrinitrate (GTN) an "internal hemodilution" (i.e. a fluid shift from the extravascular fluid to the intravascular compartment) was observed. Therefore, we found it of interest to study the effects of the long-acting PETN on parameters of hemorrheology. METHODS: The effects of single doses of 25, 50, and 80 mg PETN, 0.4 mg GTN, and of placebo were investigated on the capillary erythrocyte velocity (CEV; Capiflow), the tissue oxygen tension (tcpO2), the deformability of red blood cells, the plasma viscosity and of the fibrin content of the plasma in a single-blind, randomized study over 12 h in 12 healthy female and male volunteers. The CEV and the tcpO2 were measured in the nailfold of the fourth finger and on the skin of its end phalanx, respectively. Statistical analysis was performed by analysis of variance, the calculation of epsilon (Greenhouse-Geisser), and the multiple t test. RESULTS: After administration of 50 or 80 mg PETN the CEV decreased by 30% over a period of 2 or 4 h (p = 0.02 or 0.002). A decrease by 11% was measured 1 and 2 h after administration of GTN (p = 0.034). Under the same PETN doses tcpO2 increased from 1.41 to 1.78 mm mercury (p = 0.002). The deformability of red blood cells was slightly increased after 50 and 80 mg PETN under share rates of 60 Pa from 55.5 to 58.0% 8 and 12 h after intake. The plasma viscosity was decreased after intake of 50 mg PETN 4 to 8 h (1.36 vs. 1.34 Pa x s, p = 0.023) and after intake of 80 mg 2 to 12 h post dose (1.36 vs. 1.33 Pa x s, p = 0.015). The systolic or diastolic blood pressure decreased, but was not significant. CONCLUSIONS: The PETN-induced decrease in CEV can be explained with the pre- and afterload decreasing properties of the nitrates. The increase in tcpO2 and erythrocyte deformability and the decrease in viscosity are additional advantageous effects on the microcirculation. If the results are transferred from the nailfold of the finger to the myocardium, the benefit of nitrates could not only be seen in the decrease in preload due to their vasodilating properties, but also in improving the parameters of microcirculation. The internal hemodilution and the slightly enhanced deformability might provide an additional supply of myocardial capillaries in case of myocardial ischemia.     

The sequence of a subtilisin-type protease (aerolysin) from the hyperthermophilic archaeum Pyrobaculum aerophilum reveals sites important to thermostability

The hyperthermophilic archaeum Pyrobaculum aerophilum grows optimally at 100 degrees C and pH 7.0. Cell homogenates exhibit strong proteolytic activity within a temperature range of 80-130 degrees C. During an analysis of cDNA and genomic sequence tags, a genomic clone was recovered showing strong sequence homology to alkaline subtilisins of Bacillus sp. The total DNA sequence of the gene encoding the protease (named "aerolysin") was determined. Multiple sequence alignment with 15 different serine-type proteases showed greatest homology with subtilisins from gram-positive bacteria rather than archaeal or eukaryal serine proteases. Models of secondary and tertiary structure based on sequence alignments and the tertiary structures of subtilisin Carlsberg, BPN', thermitase, and protease K were generated for P. aerophilum subtilisin. This allowed identification of sites potentially contributing to the thermostability of the protein. One common transition put alanines at the beginning and end of surface alpha-helices. Aspartic acids were found at the N-terminus of several surface helices, possibly increasing stability by interacting with the helix dipole. Several of the substitutions in regions expected to form surface loops were adjacent to each other in the tertiary structure model.     

Viscoelasticity of living cells allows high resolution imaging by tapping mode atomic force microscopy

Application of atomic force microscopy (AFM) to biological objects and processes under physiological conditions has been hampered so far by the deformation and destruction of the soft biological materials invoked. Here we describe a new mode of operation in which the standard V-shaped silicon nitride cantilever is oscillated under liquid and damped by the interaction between AFM tip and sample surface. Because of the viscoelastic behavior of the cellular surface, cells effectively "harden" under such a tapping motion at high frequencies and become less susceptible to deformation. Images obtained in this way primarily reveal the surface structure of the cell. It is now possible to study physiological processes, such as cell growth, with a minimal level of perturbation and high spatial resolution (approximately 20 nm).     

基于降阶模型的斜拉索振动的半主动神经网络控制

根据模态降阶理论,获得了斜拉索-阻尼器系统的降阶模型,有效地缩减了系统的自由度.根据ER/MR阻尼器特性和主动控制中LQG控制理论,建立了面向速度剪切的半主动LQG控制方法,并获得了很好的控制效果.本文设计了神经网络的观测器,使用的传感器数目大大减少,根据智能控制理论,设计了神经网络控制器,并提出采用该神经网络作斜拉索半主动控制的控制算法.振动仿真的结果表明,经过离线训练后的神经网络观测器和控制器,有效地抑制了斜拉索的振动.     

熔炼低品位电子废料中铜的湿法冶金选择性回收

比较从低品位电工电子废料中选择性回收铜的3种湿法冶金方法。首先将废料熔炼成Cu?Zn?Sn?Ag合金,并采用SEM?EDS和XRD进行表征。对合金进行阳极溶解,首先采用氨溶液和硫酸溶液对合金进行电沉积或在氨?硫酸铵溶液中浸出,然后进行电沉积铜。实现了各种金属分离,Pb、Ag 和Sn等沉积在阳极泥中,而铜则转移至电解液中并在阴极上还原析出。最佳的处理条件为在硫酸溶液中浸出,获得的最终产品为高纯Cu(99%),电流效率为90%。采用氨浸出可使Cu离子富集在电解液中,利于后续的电沉积,但是自发溶解的速率较低。在氨?硫酸铵溶液中进行阳极溶解不利于各种金属在阳极泥、电解液和阴极沉积物进行分离。