Electrosprayed and selenized Cu/In metal particle films

Nano-particulate copper and indium metal layers of 1-2 μm have been deposited by non-vacuum techniques such as doctor blade, screen printing and electrospray using alcoholic suspension pastes. Electrospray showed a high efficiency of material usage and yielded the most uniform morphology. The metal precursor layers were subjected to a thermal treatment (500-600 °C) in selenium vapor to convert the porous metal layers into CuInSe₂ compound layers. The chemical conversion, investigated by X-ray diffraction, showed the presence of the In₂O₃ impurity phase in the precursor as well as in the selenized layers.     

Variation de la plombemie en fonction de la contamination par le plomb de l'eau livree a la consommation: Variation of the blood lead level as a result of lead contamination of the subjects drinking water

The combination of the chemical aggressivity of water and lead piping, as is well known, can cause severe cases of lead poisoning in those who consume such water. After a great number of observations and epidemiological studies which have strongly incriminated this metal in a wide range of pathologic conditions, other materials have been gradually substituted for lead; however, the problem remains.In compliance with a European Directive to survey the risk of lead poisoning (Council Directive, 1977), a random sample of 321 residents was selected from the Vosgian Mountains of France. This region is noted for its high incidence of cases of lead poisoning: 150 reported during 8 months in 1983 (Barbier et al., 1983).During the course of a health evaluation, a blood sample was taken from each subject for lead analysis. At the same time, a sample of tap-water (after running for 5 s) was taken from each subject home. Both lead analyses (blood and water) were performed by electrothermal atomization-atomic absorption spectrophotometry. Because of the log-normality of the distributions of the blood lead levels and the concentrations of lead in the drinking water, a logarithmic transformation was performed so that the results are expressed as the geometric mean, which for the amount of lead in the drinking water of our sample was found to be 0.16 mg l^?1.Among the subjects of this study, 28% are served by water containing more than 0.10 mg l^?1 of lead (the standard for France) and 48% by water containing more than 0.05 mg l^?1 (the European and WHO standard). In concurrence with numerous authors, our study indicates that, among our subjects, the blood lead level is much higher in men than in women (geometric means 22.9 and 15.0 μg dl^?1 respectively); this difference is highly significant (t-test:P < 0.001). Table 1 summarizes the results, by sex, obtained in this region compared with those from a study (Huel, 1982) concerning an urban French population whose geometric mean blood lead levels were 15.9 μg dl^?1 for men and 11.4 μg dl^?1 for women. The irrespective of sex, is highly significant (P < 0.001). Table 2 shows the significance of the relation between these subjects, high blood lead levels and the concentration of lead in their drinking water, while Fig. 1 shows that for contamination levels up to 0.02 mg l^?1 of lead in water, the blood lead level remains relatively stable, while above this apparent “threshold” value, the blood lead level begins to increase finally reaching quite high values in response to high contamination levels, suggesting a direct translation of increases in the water above the 0.02 mg l^?1 level to increases in the blood.     

Improvement of the optical properties of electrodeposited CuInSe2 thin films by thermal and chemical treatments

Cu, In and Se have been codeposited in thin films by potentiostatic one-step electrodeposition. The as-deposited material has shown direct optical transitions attributable to the CuInSe₂ semiconductor, but also additional absorption corresponding to another semimetallic phase. The secondary phases are selenium and copper selenide compounds which have been determined by composition measurements. In order to eliminate the semimetallic phases and to improve the semiconductor behaviour of the electrodeposited material, thermal and chemical treatments have been performed. After heat-treatment of the samples at 400°C in flowing argon, elemental selenium loss has been detected together with an enhancement of the allowed direct optical transition. The subsequent chemical etching of the layers in a KCN solution has showed to be successful in eliminating the copper selenide phases which were responsible of the remaining sub-bandgap absorption.     

大井眼卡簧式铅封防砂封隔器的研制

为保证大井眼防砂井正常生产,研制了卡簧式铅封防砂封隔器。该封隔器主要由坐封机构、丢手装置、复合铅封组件及导向系统组成。卡簧式坐封机构的设计增大了坐封锁紧力,同时保证坐封安全可靠;滑块式丢手装置有效避免了刚体伤害;另外复合铅封组件采用内带刚性结构的高密度柔性石墨结构,耐温达350℃,适应稠油热采要求。室内试验和现场应用表明,该工具创新性强,综合性能安全可靠,能很好地满足φ244.5 mm(95/8英寸)套管完井生产的需要。     

Discrete-time spare ordering policy with randomized lead times and discounting

The paper considers a generalized discrete‐time order‐replacement model for a single unit system, which is subject to random failure when in operation. Two types of discrete randomized lead times are considered for a spare unit; one is for regular (preventive) order and another is for expedited (emergency) order. The model is formulated based on the discounted cost criterion. The underlying two‐dimensional optimization problem is reduced to a simple one‐dimensional one and then the optimal ordering policy for the spare unit is characterized under two extreme conditions: (i) unlimited inventory time and (ii) zero inventory time for the spare unit. A numerical example is used to determine the optimal spare‐ordering policy numerically and to examine the sensitivity of the model parameters.     

聚合磷硫酸铁制备及净化含铅废水的试验研究

以钛白粉副产品绿矾为主要原料,氯酸钠作氧化剂,调节亚铁离子与硫酸根离子之间摩尔比后微波作用仅几分钟就能合成出液体聚合硫酸铁,并在此基础上加入磷酸根离子可得到所需絮凝剂--聚合磷硫酸铁;试验了该絮凝剂最佳合成工艺条件;采用该试剂净化含铅废水,取得了较好去除效果,并且探讨了除铅最佳试验条件.     

铅锌选矿厂废水回用研究

简述了铅锌选厂废水回用小型试验及工业试验情况，在基本上不改变工艺结构基础上改变药剂制度达到废水回用的目的，使选矿废水回用率达到80％，实现尾矿库废水零排放。     

大截面导线一牵二张力架线的要点及措施

利用现有的牵张设备和工器具，在三峡至广东500kV直流输电线路工程中，分两次一牵二张力展放大截面导线（ACSR-720／50）。这种施工工艺，在紧线及附件安装过程中采取的不同于以往的措施，起到了很好的效果，既安全可靠，又节约一次性投资。     

从铅阳极泥处理后的渣料中综合回收有价金属的生产实践

叙述了从铅阳极泥回收金银后的渣料中综合回收有价金属的生产实践。根据渣料性质，将火法和湿法工艺相互结合，使渣料中的锑、铋、金、银、铅、铜得以较彻底的分离和回收。     

穿壁焊极柱合金探索

本文对起动用铅酸蓄电池穿壁焊极柱用合金配方进行了探索 ,并得到了良好的应用效果