选择性螯合滴定法测定电镀液中的锡铜铅

本文提出的简易、快速测定方法是用ＥＤＴＡ螯合锡（Ⅳ）、铜（Ⅱ）、铅（Ⅱ）和其它金属离子，然后分别用三羟基甲酸、巯基丁二酸和氨荒丙酸解蔽。释放出的ＥＤＴＡ用锌标准液返滴定（ＸＯ－ＣＰＢ为混合指示剂），终点变化相当敏锐。研究了测定锡、铜、铅时共存离子的干扰。此法已被成功应用于测定锡－铜－铅合金电镀液及其镀层中的锡、铜和铅。     

选择性螯合滴定法测定电镀液中的铜

报道了用简易、快速的螯合滴定法测定电镀液中的铜,方法是先用EDTA螯合铜(Ⅱ)及其它金属离子,然后用巯基乙酸(TGA)解蔽、释放。研究了在测定铜、一般共存离子的干扰及消除。此法已被用于电镀液中铜的分析。     

复合电沉积铅合金工艺的研究现状

阐述了国内外不同铅合金的各种电镀液的研究现状。重点阐述了铅-锡合金镀液、铅-银合金镀液、铅-锡-锑巴氏合金镀液、各种铅复合沉积镀液等的组成及性能特点。指出了镀铅及铅合金电解液存在的问题,并对未来铅合金电镀液的发展趋势进行了展望。     

铜锡合金电镀液中铜、锡含量的测定

提出采用交流示波极谱法连续测定铜锡合金电镀液中铜锡的含量。该方法不用指示剂,利用铅标准溶液及EDTA标准溶液,借助交流示波极谱仪中示波图上．TPB切口的出现检测终点。通过实验确定酸度为5．8、掩蔽剂为硫脲。对该方法与指示剂法分析结果进行了比较。结果表明,该方法的精密度更高,准确度更好,是一种快速、简便、经济实用且无污染的测定镀铜锡合金电镀液中铜锡含量的新方法。     

柠檬酸盐铅锡合金电镀溶液中铜,铁的连续测定

在柠檬酸盐铅锡合金电镀过程中,杂质的多少对镀层的质量有着很大的影响。当镀液中铁和铜的含量迟到一定量时,镀层就会粗糙、发黑,可焊性明显下降。因此需要对镀液中铜和铁的含量进行测定。本文提出用硫酸将铅沉淀,用过硫酸铵破坏柠檬酸盐,用久氟化铵掩蔽锡,在pH=2的情况下,以磺基水杨酸为指示剂,用EDTA滴定铁,再用氨水调节pH=8-9,再用EDTA滴定钢。本法是连续滴定,操作简单、易掌握,终点明显,结果完全符合电镀液分析的要求。     

无氟电镀锡铅合金新工艺的应用

本文介绍无氟的以羟基烷基磺酸作络合剂电镀锡铅合金在生产上的应用。羟基烷基磺酸型电镀锡铅合金与传统的氟硼酸型镀液相比,其突出优点:(1)不含氟,有利于环境保护;(2)镀液配制相当简单;(3)镀液稳定易于维护;(4)电流密度变化,镀层中锡铅比稳定;(5)镀层中铅的百分含量与镀液中铅的百分含量成正比,易于得到预定组成的镀层;(6)分散能力和深镀能力好,滚镀挂镀均适用。     

专利实例

铜-锌合金电镀液,锡-铜合金电解液,铅-锡合金酸性镀液,电镀锡-铋合金络合剂及其制备方法,锡-锌合金电镀液,三价铬镀铬电解液。     

铅-锡合金电镀液中铅、锡的连续测定

<正> 电镀液的分析,要求快速、简便、准确。本工作采用络合滴定,满足了这些要求。在做好准备工作的情况下,20分钟内能够得出双样结果。在pH5～6的缓冲溶液中,铅离子和四价锡离子均能与乙二胺四乙酸根(EDTA~(2-))生成1:1的络合物。但Sn-EDTA 络合物能被氟离子解络而析出相当量的EDTA。以二甲酚橙作指示剂,用锌液滴定析出的EDTA,即可测出锡的含量,铅的含量则根据其络合所消耗的EDTA 算出。方法的终点颜色变化明显。同时,对镀液的各种成分进行了干扰影响实验。实际镀液分析表明,锡和铅的测定精密度分别约为0.6%和1%。     

印刷线路板半光亮酸性镀锡工艺

为解决印刷线路板传统锡-铅合金电镀工艺的铅氟环境污染问题,对硫酸亚锡-β-萘酚酸性纯锡电镀工艺进行了研究.采用赫尔槽法、人工加速腐蚀法、SEM、XRD等方法测定了镀液各组分对镀液性能及镀层质量的影响.得到该体系适宜的工艺条件:硫酸亚锡30 g/L,硫酸70 mL/L,β-萘酚0.5 g/L,明胶1 g/L,1～3 A/...     

柠檬酸盐全光亮镀锡铅合金溶液分析

柠檬酸盐全光亮镀锡铝合金工艺是国内外一顶新颖的工艺、其溶液含有氯化亚锡、碱式碳酸铅、柠檬酸及其盐、乙二胺四乙酸二钠等主要成份以及电镀过程中产生的四价锡、下面兹介绍这些成份的分析方法. 碱式碳酸铅的测定一方法摘要锡铅合金镀液中锡、铅等金属离子以二价金属离子的络合物形式存在于镀液中,加入硫酸,则铅呈硫酸铅沉淀从铅的络合物形式中析出.因而可用重量法或硫酸铅沉淀-EDTA络合滴定法,求得     

Aluminum,Arsenic, Beryllium,Cadmium, Chromium,Cobalt, Copper,Iron, Lead,Mercury, Molybdenum,Nickel, Platinum,Thallium, Titanium,Vanadium, and Zinc: Molecular Aspects in Experimental Liver Injury

Experimental liver injury with hepatocelluar necrosis and abnormal liver tests is caused by exposure to heavy metals (HMs) like aluminum, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, mercury, molybdenum, nickel, platinum, thallium, titanium, vanadium, and zinc. As pollutants, HMs disturb the ecosystem, and as these substances are toxic, they may affect the health of humans and animals. HMs are not biodegradable and may be deposited preferentially in the liver. The use of animal models can help identify molecular and mechanistic steps leading to the injury. HMs commonly initiate hepatocellular overproduction of ROS (reactive oxygen species) due to oxidative stress, resulting in covalent binding of radicals to macromolecular proteins or lipids existing in membranes of subcellular organelles. Liver injury is facilitated by iron via the Fenton reaction, providing ROS, and is triggered if protective antioxidant systems are exhausted. Ferroptosis syn pyroptosis was recently introduced as mechanistic concept in explanations of nickel (Ni) liver injury. NiCl₂ causes increased iron deposition in the liver, upregulation of cyclooxygenase 2 (COX-2) protein and mRNA expression levels, downregulation of glutathione eroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), nuclear receptor coactivator 4 (NCOA4) protein, and mRNA expression levels. Nickel may cause hepatic injury through mitochondrial damage and ferroptosis, defined as mechanism of iron-dependent cell death, similar to glutamate-induced excitotoxicity but likely distinct from apoptosis, necrosis, and autophagy. Under discussion were additional mechanistic concepts of hepatocellular uptake and biliary excretion of mercury in exposed animals. For instance, the organic anion transporter 3 (Oat3) and the multidrug resistance-associated protein 2 (Mrp2) were involved in the hepatic handling of mercury. Mercury treatment modified the expression of Mrp2 and Oat3 as assessed by immunoblotting, partially explaining its impaired biliary excretion. Concomitantly, a decrease in Oat3 abundance in the hepatocyte plasma membranes was observed that limits the hepatic uptake of mercury ions. Most importantly and shown for the first time in liver injury caused by HMs, titanium changed the diversity of gut microbiota and modified their metabolic functions, leading to increased generation of lipopolysaccharides (LPS). As endotoxins, LPS may trigger and perpetuate the liver injury at the level of gut-liver. In sum, mechanistic and molecular steps of experimental liver injury due to HM administration are complex, with ROS as the key promotional compound. However, additional concepts such as iron used in the Fenton reaction, ferroptosis, modification of transporter systems, and endotoxins derived from diversity of intestinal bacteria at the gut-liver level merit further consideration.     

THERMOPLASTIC,FLEXIBLE, AND RECYCLABLE COMPOSITES,DESIGN, PREPARATION,AND CHARACTERIZATION

Glass fiber reinforced composites based on thermosets are the traditional materials used for many applications due to their good mechanical properties. The non-recyclability of these materials has led to the necessity to develop thermoplastic composites and industrial processes for their manufacture [1]. The present paper deals with the preparation of thermoplastic pre-pregs unidirectionally reinforced with Twarn® and their mechanical characterization.     

DUO-ICP-AES测定精对苯二甲酸中的钴、铬、铁、锰、钼、镍、钛

采用DUO-ICP-AES同时测定精对苯二甲酸中钴、铬、铁、锰、钼、镍、钛,并对仪器的分析线选择、背景校正、入射功率、雾化器压力、辅助气流量、冷却气流量、蠕动泵转速的影响及共存元素的干扰、硝酸铯灰化助剂等因素进行了详细的研究。方法的检测限:钴0.0097 mg/L;铬0.0021 mg/L;铁0.0078 mg/L;锰0.0012 mg/L;钼0.0027 mg/L;镍0.016 mg/L;钛0.0027 mg/L,回收率和精密度分别为93.0%～99.5%和0.37%～3.2%。该方法快速简便,具有良好的精密度和准确度,适用于进出口精对苯二甲酸的日常检验。     

Pd-, Ni-, Fe-, and Co-Catalyzed Cross-Couplings Using Functionalized Zn-, Mg-, Fe-, and In-Organometallics

The development of new methods for preparing polyfunctional organometallics has made a broad range of such reagents available for various transition metal-catalyzed cross-couplings. An overview of the most general preparation methods will be presented. Applications to practical cross-coupling procedures will be covered, emphasizing the functional group compatibility and the reaction scope.     

Sylvatraxx树脂对半钢子午线轮胎胎面胶性能的影响

本文研究了Arizona Chemical公司生产的胎面增强助剂（Tread Enhancement Additive-TEA）Sylvatraxx 4401对半钢子午线轮胎胎面胶性能的影响。结果表明：Sylvatraxx 4401的加入有利于提高白炭黑的分散性,改善混炼胶的加工性能和硫化胶的物理机械性能,能够明显提高胎面的抗湿滑性。随着Sylvatraxx 4401用量的增加,白炭黑在胶料中的分散进一步提高,混炼胶的门尼粘度降低;硫化胶的压缩生热和阿克隆磨耗降低,0oC的tanδ明显提高的同时60oC的tanδ略微降低,有利于胎面胶抗湿滑性能的提高和滚动阻力、动态生热的降低。