海产品中多聚磷酸盐的离子色谱法测定

本文建立了一种采用去离子水提取，三氟乙酸作为蛋白沉淀剂对海产品样品进行前处理，采用淋洗液自动发生装置在线产生KOH进行梯度淋洗，抑制型电导离子色谱法，检测海产品样品中多聚磷酸盐的方法。本文亦比较讨论了不同沉淀剂对保留时间和加标回收率的影响。该方法具备抗干扰能力强，选择性好，灵敏度高，对环境友好等特点。实际样品检测结果令人满意。     

离子色谱法测定水产品中的多聚磷酸盐

本文建立了一种采用离子色谱法,抑制型电导检测水产品中多聚磷酸盐的方法。选择的色谱条件为IonPac AS11-HC离子交换柱,KOH梯度淋洗,抑制型电导检测对其进行测定。水产品样品经过用沸水灭活酶、蛋白质沉淀、离心、分液等一系列的样品前处理后进样分析,消除了基体干扰。该方法线性相关系数r大于0．999,实际样品RSD小于3％,具有灵敏度高,选择性好,操作简单,价格便宜,对环境友好等特点。     

Structural Changes in Electric Discharge Machining by Dissimilar Tool Electrodes

Russian Engineering Research - The structure of the machined surface after the copy electric discharge machining (broaching) of quenched 40Х steel by various tool electrodes is investigated....     

稀土锌基(C,Si)复合材料的结构阻尼特性

分析研究了稀土锌基（C，Si）复合材料的结构阻尼特性。结果表明，硅颗粒显著提高复合材料的刚性，对复合材料的阻尼特性无明显影响；石墨颗粒显著提高复合材料的阻尼特性。对复合材料的刚性无明显影响。     

锌基合金制模技术

用于车辆覆盖件拉伸成形的模具,通常是先用铸钢制坯,再经仿形铣等加工而成,这无疑是最可靠的方法。但这种方法的缺点是设计、生产周期长,成本高,对模具加工设备和成形压力设备的要求也较高。特别是凹面、曲面加工比较困难,成形面的配合也往往不尽人意,因此,只适合于定型的大批量生产的模具加工。而对于新产品试制、小批量生产以及对成形件精度要求不十分高的产品生产,低熔点合金模则充分显示其经济快捷的特点。我厂 FC— 1205型农用运输车驾驶室的前围、顶盖、左右后围角等凹面曲面较多的覆盖件,都是用锌基合金模压制而成的。[1]…     

切削锌基合金应注意的问题

作为一种新型材料,生产中会有一些新的问题。本文从合金本身的性能出发,对生产中切削锌基合金常遇见的问题进行分析,并得出相应的解决方法。     

Magnetic Acoustic Emission in Ferromagnetic Materials. 3: Effect of Structural Changes on Magnetic Acoustic Emission (Review Article)

This part of the review is devoted to effects of structural changes in multiply alloyed ferromagnetic materials on parameters of magnetoelastic acoustic emission.     

络合滴定法测定镀锌钢丝中锌层质量

介绍了采用邻菲罗啉定量解蔽锌,用硝酸铅标准溶液定量滴定置换出的EDTA来测定锌含量的方法.采用本方法测定镀锌层操作简便,结果准确.     

结构拓扑优化设计的研究现状及其应用

介绍了结构拓扑设计的发展过程和主要的数学模型;分析了目前存在的拓扑数值稳定性问题和这些问题的常用处理技术;描述了优化准则法、序列线性规划法和移动渐进线法三种常用的优化算法;举例说明了拓扑设计在静态结构、动态特性和柔性机构设计中的应用;根据国内外目前在结构拓扑设计领域的研究现状和笔者的科研经验,总结了拓扑设计今后研究的重点内容和发展方向。     

阳泉市农田土壤中有效锌的含量及分析

为全面掌握阳泉市农田土壤中微量元素有效锌的分布状况,在全市范围内根据地力条件在作物收获后采集土样,进行微量元素有效锌的分析检测。检测结果显示:全市农田土壤中有效锌含量比较丰富为促进农业产业化提供科学依据。     

硼酸锌超微粒子在水溶液中的摩擦学性能研究

采用沉淀法原位合成了油酸钠修饰硼酸锌纳米颗粒,用透射电子显微镜(TEM)和红外光谱(IR)对其形貌和表面结构进行了表征,用四球机考察了其在水中的摩擦学性能,用扫描电子显微镜(SEM)观察了磨斑表面形貌,用X射线光电子能谱(XPS)分析了试球磨斑表面的化学成分.结果表明:制备的油酸钠修饰硼酸锌纳米粒子粒径在80～100 nm,能在水中均匀分散,可使水的承载能力显著提高,抗磨减摩性能也有较大提高.XPS分析表明,硼酸锌纳米粒子作为水基润滑剂,在摩擦过程中在摩擦副表面生成了Zn、B、Fe等的氧化物保护膜, 起到良好的抗磨减摩作用.     

Tribochemistry of Bulk Zinc Metaphosphate Glasses

Zinc polyphosphate glasses are the principal component of the antiwear tribofilms formed on steel surfaces in the presence of additives, such as zinc dialkyldithiophosphates. In this work, amorphous, zinc metaphosphate glasses have been synthesized and characterized by means of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), elemental analysis, and X-ray photoelectron spectroscopy (XPS). Tribological tests were performed by rubbing steel balls against the zinc metaphosphate discs in a poly-α-olefin (PAO) bath at room temperature. XPS was used in order to characterize the tribostressed areas on both metaphosphate discs and steel balls. A transfer film, constituted of iron and zinc polyphosphates, was formed on the contact area of the balls. This transfer film was found to reduce friction and prevent ball wear. A reduction in the relative intensities of XPS signals related to bridging-oxygen species and a binding energy shift of 0.4 eV of the P 2p toward lower values demonstrated the presence of shorter-chain-length phosphates inside the tribo-tracks on the discs. Furthermore, iron was transferred to the glass during the tribological tests. A tribochemical reaction between zinc metaphosphate and iron oxide has been proposed as an explanation for the depolymerization of the glass and the formation of iron phosphate.     

火焰原子吸收法测定核桃粉中钙和锌的研究

采用硝酸—高氯酸混酸为溶剂 ,湿法消解 ,氯化镧消除磷对钙的干扰 ,用火焰原子吸收法测定钙和锌。分析结果表明 ,方法简便快速 ,结果满意     

环氧富锌预涂底漆在和谐D2机车上的应用

通过环氧富锌预涂底漆极好的焊接施工性、防腐蚀性和与钢材极好的附着力等优越性能以及在同车公司铁路机车钢材预处理上的应用介绍,总结了该预涂底漆的施工工艺和注意事项,提高了铁路电力机车的防腐性能,达到延长机车车辆使用寿命的要求,这项工艺已应用在HXD2系列机车顶盖上,使用效果非常好。     

Boundary Lubrication by Pure Crystalline Zinc Orthophosphate Powder in Oil

The aim of this study is to assess the tribological behavior of pure crystalline zinc orthophosphate under boundary lubrication in order to model zinc phosphate-based anti-wear additives. Boundary films were generated from α-Zn₃(PO₄)₂ powder dispersed in poly-alpha-olefin oil, at ambient temperature, by means of a steel sphere-on-flat contact in reciprocating motion. Electrical contact resistance and friction coefficient evolutions enable an understanding of the tribological behavior of crystalline zinc orthophosphate at the sliding interface. A conductive atomic force microscope (C-AFM) equipped with a current sensing setup, Raman spectroscopy, and nano-indentation were used to characterize the resulting film. When involved in a tribological contact, zinc orthophosphate powder forms a continuous patchy adherent film, changing its structure to amorphous orthophosphate, on both sliding steel surfaces. Morphological and mechanical properties of the film are discussed with respect to the ZDTP tribofilm models.     

稀土元素在热镀锌中的应用及研究进展

综述了稀土在热镀锌中的应用及研究进展,包括稀土元素对镀锌层的耐腐蚀性能、对镀层作用及稀土添加量方面的研究,并指出了稀土在热镀锌行业中发展趋势。     

火焰原子吸收光谱法测定荞麦中铁锌钙的含量

试验旨在研究养麦中铁、锌、钙的含量并筛选优异材料。用混合酸--火焰原子吸收光谱法测定了来自云南省的54份养麦材料中的铁、锌、钙的含量。铁、锌、钙的平均含量分别为59．1μg/g、38．5μg/g、179．4μg/g，变异系数分别为45％、24．8％、18．9％，结果表明这批材料中铁、锌两个元素的变异丰富。初步鉴定出12份铁含量和4份锌含量高的材料。     

The Antiwear Action of Zinc Di-n-Butyl Phosphate

The dynamics of MoS₂ particles in a mineral oil dispersion are studied in the same manner as reported in Part I for graphite dispersions. A Hertzian contact consisting of a steel ball in contact with a glass disk is lubricated with MoS² dispersions and observed by optical microscopy at various. slide/roll conditions. In general, the behavior of MoS₂ and graphite are similar. That is, the solids lend to enter the contact and form a film on the contacting surfaces whenever a rolling component of motion is used, but solid particles seldom enter the contact during pure sliding. MoS₂ has more pronounced plastic flow behavior than graphite. However, the polished steel ball is more readily scratched by MoS₂ than by graphite. Under the conditions of these studies, lower friction and wear are observed with pure oil rather than with the dispersions. However, under other conditions (such as different contact geometry or rougher surfaces), the solid-lubricant dispersions might be beneficial.     

锌合金手机壳压铸技术

介绍手机外壳典型模具的流道设计和锌合金原料的科学使用,包括流道和溢流槽开设、原料型号的合理选择等,并对生产控制的办法进行了分析。     

含锌废水处理方案设计

通过对某厂含锌废水处理几种方案的分析与研究,得出了化学沉淀-混凝法是处理含锌废水的最佳方案,它操作简便,技术成熟,易于控削,能达到预期效果.