泾渭牌GL系列电镀溶液过滤机

电镀溶液过滤机是净化镀液和提高镀件质量不可缺少的设备。为便于电镀行业选用,将泾渭牌过滤机的性能、特点作简单介绍。青岛气割机械厂是生产电镀溶液净化设备的专业厂。十多年来,该厂通过反复实践,广泛吸收了国内外     

导电排电刷镀光亮锡技术

传统的导电排的电镀工艺是采用挂镀技术,但电刷镀技术在导电排电镀工艺中的应用越来越广。介绍了电刷镀导电排的设备、工辅具、溶液及工艺,提出了克服导电排电刷镀缺点的方法。改良的电刷镀工艺对导电排镀层质量有明显提高,可实现批量、自动化生产。     

书讯

<正>《电镀工程手册》(作者:曾华梁、倪百祥)定价:79元本手册是一本从电镀工艺人员的角度介绍有关电镀设备和电镀工程的技术书籍。主要内容包括:电镀项目的工艺设计,电镀工艺选择,机械前处理设备,槽子,溶液的加热、冷却、搅拌、恒温控制及过滤,滚镀与振动镀设备、整流器和直流线,阴阳极与导电,抽风、送风和废气处理,干燥和除氢设备;电镀参数的自动控制,直线式电镀自动线,环形自动线,线(带)电镀线和水平电镀线,专用电镀线,专用辅助设备,给     

长管件封闭循环电镀法

长管零件内表面电镀,是电镀行业比较棘手的问题。采用通常的电镀方法,需要很多较大的设备和起重输送设备,还需配制较多的电镀溶液。对于批量不大的一次性生产的单位来说,若以巨额投资购置设备则是很不经济的。随着炼油、航空工业的迅速发展,一些对输油质量要求较高的地方,多对输油地埋管要求内壁镀锌钝化处理。而大部分厂家又没有能镀8～10米长管的电镀设备。为了解决这一矛盾,我们摸索、总结出一种封闭式循环镀液电镀方法,较好地解决了     

磨头镍-金刚石复合镀层电镀工艺及设备

在电动组合开孔和研磨用钻头表面电镀镍-金刚石复合镀层。介绍了镍-金刚石复合电镀工艺流程、溶液配方及电镀方法;阐述了磨头电镀镍-金刚石复合镀层生产线特点,设备组成,性能要求以及设备特殊配置的制造和应用;重点阐述旋转镀和挂具的结构等。     

管形器件电镀的物理模拟

电镀过程中阴阳极板间的电压、电场,溶液中的电流及板上面电荷密度之间的内在联系是电镀研究中常常忽视的一个物理问题。利用物理模型模拟待镀管形器件双面镀的影响因素,得到了在电镀过程中器件尺寸大小及安置位置等的规律：要得到均匀的镀层,应使内阳极极棒的半径大于镀件半径的一半且靠近镀件,同时减小溶液中的离子浓度。     

周期回流电镀法

概说周期回流电镀法简称“回流法”,是电镀学上一种重要的改进。国外已有采用此法在各种溶液中进行电镀,获得良好效果,可称为电镀工业上近五十年来一个新的贡献。回流法对於一切可能电镀的金属溶液,除铬外,都可应用,例如对紫铜、锌、镉、银、黄铜、白铜及金均已成功。采用回流法进行电镀时,虽然氰化物溶液和酸性溶液同样可以获得一定效果,但用氰化物溶液比较有利些,尤其适用於厚层的电镀,对镀银、镀紫铜、镀黄酮、镀青白铜等,其功效     

羟基烷基磺酸盐电镀铅锡合金工艺实践

将羟基烷基磺酸盐电镀铅锡合金溶液的镀层性能和镀液性能与氟硼酸镀液作了对比,并对氟硼酸电镀铅锡溶液逐渐转变成羟基烷基磺酸盐铅锡镀液作了尝试。     

振动电镀技术及其发展前景

小型零件电镀所采用的传统滚镀方法存在一些固有的缺点,如溶液升温较快,允许电流密度较小,对零件产生较大的冲撞不适宜易碎零件的加工等。介绍了振动电镀工艺的特点和我国振动电镀的应用和发展历程,列举了不同类型振动电镀设备的结构特性和所适用的电镀工艺以及零件品种,并结合我国目前电镀装备实际,指出了振动电镀技术的发展前景。     

T—10快速退镀添加剂的应用

防护装饰性 Cu/Ni/Cr和Ni-Fe/Cr 电镀工艺在我国工业生产上已得到了广泛应用。在大规模生产的情况下,不可避免地总有一些不合格的次品,希望退镀后,重新进行电镀。在国外,退镀溶液一般可分为浸蚀型(化学法)和阳极型(电介法)两种。化学法退镀虽操作容易、设备简单,但药品成本高、溶液寿命短,反应物的积聚,还会导致基体腐蚀。     

佛山市顺德新城区降水中污染物的监测和分析

为掌握佛山市顺德新城区降水中污染物的情况,2015年7月至8月,文章作者分别在雨天进行了降水取样,对降水中的pH、电导率、常见阴离子(F-、Cl~-、NO_3~(2-)、SO_4~(2-))及部分重金属(铅和镉)进行监测分析。选择有相关数据的珠江三角洲和石家庄、厦门等地的降水中污染物的情况进行对比。结果表明,顺德新城区降水中的p H和部分阴离子浓度优于珠江三角洲平均值,酸雨类型属于硫酸和硝酸混合型;其水体洁净程度略差于石家庄;铅和镉的浓度也高于厦门,甚至部分超出了人体能直接接触的安全范围。     

Metabolism of trideuterated iso-lignoceric acid in rats in Vivo and in human fibroblasts in culture

Saturated very long chain fatty acids (fatty acids with greater than 22 carbon atoms; VLCFA) accumulate in peroxisomal disorders, but there is little information on their turnover in patients. To determine the suitability of using stable isotope-labeled VLCFA in patients with these disorders, the metabolism of 22-methyl[23,23,23-²H₃]tricosanoic (iso-lignoceric) acid was studied in rats in vivo and in human skin fibroblasts in culture. The deuterated iso-VLCFA was degraded to the corresponding 16- and 18-carbon iso-fatty acids by rats in vivo and by normal human skin fibroblasts in culture, but there was little or no degradation in peroxisome-deficient (Zellweger’s syndrome) fibroblasts, indicating that its oxidation was peroxisomal. Neither the 14-, 20-, and 22-carbon iso-fatty acids nor the corresponding odd-chain metabolites could be detected. In the rat, the organ containing most of the iso-lignoceric acid, and its breakdown products, was the liver, whereas negligible amounts were detected in the brain, suggesting that little of the fatty acid crossed the blood-brain barrier. Our data indicate that VLCFA labeled with deuterium at the ω-position of the carbon chain are suitable derivatives for the in vivo investigation of patients with defects in peroxisomal β-oxidation because they are metabolized by the same pathways as the corresponding n-VLCFA. Moreover, as iso-VLCFA and their β-oxidation products are readily separated from the corresponding n-fatty acids by normal chromatographic procedures, the turnover of VLCFA can be more precisely measured. A preliminary report of part of this work (Reference 18) was presented at the 5th International Symposium on the Synthesis and Applications of Isotopes and Isotopically Labelled Compounds, Strasbourg, France, June 20–24, 1994.     

高效液相色谱法分析化妆品中微量成分的研究进展

综述了高效液相色谱法在化妆品中防腐剂、防晒剂中紫外线吸收剂以及性激素的检测等几个方面的应用;同时,介绍了分析所用的色谱柱、流动相、使用的检测手段以及样品的提取方法;最后针对目前存在的问题,提出了高效液相色谱用于化妆品中微量成分分析的研究方向和发展前景。     

Denitrification in shallow groundwater in a coastal agricultural area in Japan

In a coastal agricultural area in the central part of Japan (Shizuoka), we found decreasing nitrate concentration with depth in a shallow groundwater, where the depth to water table varied between 0.6 and 1.2 m below ground surface. High nitrate concentrations (5–29 mg N L^–1) were often observed in the upper layer (0–2 m) of the groundwater, but the concentration decreased to less than 1 mg N L^–1 in the deeper layer. Ammonium was scarcely detected, and the concentration of dissolved oxygen was usually low (< 1 mgO₂ L^–1) in the groundwater. Nitrate in the groundwater often had very heavy nitrogen stable isotope ratios (>20{}). There was a negative relationship between nitrogen stable isotope ratio of nitrate and its concentration. When nitrate was injected into the groundwater with acetylene and bromide (a conservative tracer), nitrate concentration decreased to 20% of the initial level within 5 days, accompanied by the increase in nitrite and nitrous oxide concentration and a little change in bromide concentration. These results indicate that microbial denitrification plays a potential role in the decrease of nitrate in shallow groundwater at the study site.     

我国硝酸工业生产技术新进展

系统叙述了我国硝酸工业2000-2007年生产现状及主要技术成果,尤其指出了国产"四合一"机组的成功投运,使我国硝酸国产化装置取得较大的进步,表现在吨酸的铂耗、氨耗和能耗等方面接近国外引进装置水平,同时介绍了国外双加压法硝酸生产技术的进展.我国已成为硝酸生产大国,仍需以先进的技术改造和发展我国硝酸工业,确保我国硝酸工业健康有序地发展,加快从硝酸生产大国向强国迈进的步伐.