BZnMn9-36.5-4.5-1.0铅锌白铜的研究

确定了低镍铅锌白铜BZnMn9-36.5-4.5-1.0的合金成分，并对其金相组织、热挤压性能、切削性能、耐腐蚀性能、冷加工性能、退火性能、色度等进行了研究。研制出的低镍铅锌白铜能够满足眼镜异型材加工工艺对材料的要求，同时也有较好的经济性。     

Ti-4．4A1—3．8Mo合金的亚稳相变及其对硬度的影响

对锻态Ti-4．4Al-3．8Mo合金分别进行了β单相区和α＋β两相区（相变点之下45℃）淬火处理,研究了亚稳相变对硬度的影响．结果表明,β单相区淬火处理的样品硬度比α＋β两相区处理的样品高约10％．β单相区淬火后的相组成为全α’马氏体,自910℃的α＋β两相区淬火后的相组成为等轴初生α相＋α’马氏体＋α″马氏体．硬度出现差异的主要原因是后者中存在硬度较低的初生α相和α″马氏体．本文修正了Ti—β稳定元素二元系亚稳相图（示意图）,指出在α＋α’和α＋α″相区之间存在α＋α’＋α″相区,并使用修正后的相图解释了Ti-4．4Al-3．8Mo合金的相组成与硬度的关系．     

Tm^3＋-Yb^3＋共掺杂NaYF4蓝色上转换发光粉的合成及其性质研究

采用溶胶-凝胶（Sol—gel）法制备出2％Tm^3＋、0％～98％Yb^3＋（摩尔分数，下同）共掺杂NaYF4蓝色上转换发光粉。Yb^3＋共掺杂促进了Tm^3＋掺杂NaYF4由β相到α相的转变。在976nm半导体激光器（LD）激发下，在430-500nm和620-750nm范围内获得了蓝色和红色上转换发光。随着Yb^...     

辽西八家子沉积-热液叠加型层控铅锌矿床的成矿地质特征找矿方向

八家子铅锌矿床前人认为是“矽卡岩型矿床_通过矿区及外围含矿层位层序岩性对比及研究,该矿床为“沉积-热液叠加型层控矿床”。从铅锌、黄铁矿矿体地质产状、矿石类型、矿石结构、构造、元素组合上看,八家子铅锌矿床可分为沉积一成岩阶段、热液叠加阶段、矽卡岩作用阶段。该矿床成矿元素的垂直分带：上部为自然银＋方铅矿组合（Ag＋Pb）：中部为褐色闪锌矿＋细晶方铅矿＋粗晶黄铁矿：下部为黄铁矿（胶状、同心圆状）Fe＋Zn,黑褐色闪锌矿。     

手表摆轮用无镍铅锌白铜棒材的研制

一、前言手表的心脏——摆轮,通常是用镍含量较高的铅锌白铜(以下简称镍白铜)棒材制造的。这种材料的优点是机械性能和切削加工性能较好,零件车削后,表面呈银白色光泽,比较美观(因摆轮最后要镀金,银白色     

Al55%-Zn合金镀层钢板组织与腐蚀特性

研究了国产热浸镀Ａｌ５５％－Ｚｎ合金钢板组织结构、腐蚀行为及防蚀机理。试验结果表明，合金镀层组织是由含富铝相（α）、富锌相（β）的外层和以ＦｅＡｌ３（θ）、α－ＦｅＡｌＳｉ（Ｈ）化合物为主要相成分的内层构成。这种合金镀层是一种阳极性镀层，具有与热镀锌层相似的电化学保护作用。由于铝元素的合金化作用和Ａｌ３＋离子的掺杂效应，使镀层的腐蚀速度明显减小，仅为热镀锌层的１／４～１／６。     

MnxCd1-xIn2 Te4晶体生长研究

采用Bridgman法生长四元稀磁化合物半导体Mn0.22Cd0.78In2Te4晶体。当晶体生长到预定长度时，淬火得到固液界面。采用光学显微镜、扫描电镜、X射线衍射仪、ISIS能谱仪以及Leica定量金相分析仪研究了晶体中出现的界面形态、相的和数量以及沿生长方向的相析出规律，并进行了相成分分析。研究发现，淬火得到的Mn0.22Cd0.78In2Te4晶体中存在两个界面，其中一个为固液相变界面，另一个为由α＋β两相区发展到单相β区时的转变界面，二者相对于生长初始端均为凹形；α＋β两相区中，β相以条状、花状和近似圆片状形式存在，其中条状β相多分布在晶界处；越接近生长初始端，花状和近似圆片状β相越小，条状β相越细，它们的含量越少；X射线衍射图谱表明，β相为黄铜矿结构，α相为面心立方结构。     

Ti-31合金微观结构的TEM研究

用透射电子显微镜（ＴＥＭ）研究了Ｔｉ－３１合金微观结构。结果表明，锻件在８００℃退火缓冷条件下，合金组织存在α、α２、β及富Ｎｉ呈片状的α／β界面相；８００℃退火空冷时，其基本组织为α＋β相和界面相；相成分分析结果还表明，Ｎｉ、Ｍｏ只分布在β相和界面相中，α相中Ａｌ、Ｚｒ含量比β相中的相对高很多，造成α相Ａｌ当量高，可在α相中析出α２相。     

Pr3+/Yb3+ 共掺氟锆酸盐玻璃的热分析

在对不同ＰｂＦ２呈的Ｐｒ＾３＋／Ｙｂ＾３＋共拓的ＺＢＬＡＰＮ玻璃的差热分析后同烧结发现含ＰｂＦ２大于４．５％后，差热曲线上的析晶峰出现分裂，经扫描电镜分析，含铜量高的玻璃中出现了分相，各相所含铅量不同，这引起玻璃热稳定下降。     

TiO2／（O′＋β′）-Sialon复相陶瓷的制备与表征

以纳米TiO2粉和（O′＋β′）-SiMon粉为原料、Yb2O3或Tb2O3为添加剂，在高纯N2气氛下采用常压烧结制备出了TiO2／（O′＋β′）-Sialon复相陶瓷。采用XRD对材料进行物相、晶粒度分析，采用SEM＆EPMA对材料进行形貌观察和元素面分布分析。结果表明，随烧结温度的升高和恒温时间的延长，TiO2逐渐由锐钛矿相向金红石相转化，同时晶粒也逐渐长大。Tb2O3和Yb2O3分别对锐钛矿相变有显著的抑制和促进作用，通过控制烧结制度、添加剂种类及含量可得到不同TiO2相组成的TiO2／（O′＋β′）-Sialon。Tb2O3和Yb2O3均对TiO2晶粒生长有抑制作用，在不高于800℃的温度下烧结可得到纳米TiO2／（O′＋β′）-Sialon复相陶瓷。     

Wear and mechanical properties of carbon fiber reinforced copper alloy composites

The mechanical properties and wear behavior of lead-free metal matrix composite, and carbon fiber reinforced copper alloy composites were studied, and compared with a common leaded copper (Cu-6wt.%Zn-6wt.%Sn-3 wt.%Pb) alloy. The effects of carbon fibers and alloy element Sn on these properties were investigated. Carbon fiber/Cu–Sn–Zn composites showed higher hardness and bending strength than the leaded copper alloy when carbon fibers content is less than 12 vol.%. Tribological tests were conducted with disks made from these materials, and tested against a steel counterface. The carbon fiber/Cu–Sn–Zn composites showed higher wear resistance than the leaded copper alloy under a constant load of 50 N. Observations on surface morphology were utilized in understanding the wear properties of these materials. The results show that the wear mechanism of the leaded copper alloy is adhesive wear, while it is mainly adhesive wear accompanied by oxidative wear for the 12 vol.% carbon fiber/Cu–Sn–Zn composites. The 12 vol.% carbon fiber/Cu–Sn–Zn composites are likely to provide optimum substitutes for the leaded copper alloy under the load of 50 N.     

Assessing effect of electrode configuration on the efficiency of electrokinetic remediation by sequential extraction analysis

The electroremediation experiments were conducted on artificially polluted soils by introducing a single metallic contaminant (Pb, Zn and Cu) and multiple metallic contaminants (Pb+Zn+Cu). Based on sequential extraction results, it was observed that the removal efficiencies of lead, zinc and copper vary depending on types of contamination. When the soil was contaminated only by lead, the removal efficiency was found to be 48%. However, the removal efficiency of lead decreased to 32% when the soil was contaminated by the combination of lead, zinc and copper. Similar results were observed for zinc and copper. The corresponding removal efficiency values for zinc and copper were 92% and 37%, and 34% and 31%, respectively. Effects of electrode geometry on the removal efficiency of metals were investigated by constructing a multiple anode arrangement. In this arrangement, the electrokinetic unit consists of three cylinders, which lie one inside the other, and the soil was placed in the middle cylinder. The central cylinder was the cathode well and the outer cylinder was the anode well, where eight identical anode electrodes were placed in octagonal with respect to the cathode electrode. By using this electrode arrangement in removal of metals from the soil contaminated with the combination of three metals (Pb+Zn+Cu), the removal efficiencies of lead, zinc and copper were found to be 29%, 18% and 18%, respectively. As it can be seen, these numerical values are much lower than the values that were obtained when the traditional two-plate electrode arrangement used in the electroremediation experiments (32%, 37% and 31%).     

Effects of Oral Zinc Therapy on Liver Functions and Serum-Liver Distribution of Zinc and Copper in Patients with Bilharzial Periportal Tract Fibrosis

Abstract

Zinc; copper; total proteins; albumin; globulin, total bilirubin; ASAT and ALAT were determined in serum of 41 bilharzial patients with various degrees of periportal tract fibrosis (PTF). Zinc and copper in liver biopsies were also measured in addition to the intrasplenic portal pressure. 13 patients showed moderate PTF on histopathological examination. Ten of them have agreed to receive zinc sulphate. 7 H2O orally in gelatinous capsules t.d.s for 15 days. Each patient received 75 mg zinc/day. The same parameters were again determined after zinc therapy.

In all patients (11 male + 30 female), the degree of PTF showed inverse correlation with liver zinc content and direct correlation with serum zinc level. Also PTF showed inverse correlation with both serum and liver copper. However after zinc treatment in patients with moderate PTF, there was a marked increase in liver zinc content amounted to 82% while serum zinc was unchanged. Both serum & liver copper concentrations were significantly decreased by 45% & 38% respectively. Liver functions showed marked improvement following zinc treatment. The data reflected good therapeutic efficacy of zinc sulphate capsules in ameliorating the effects of bilharzial liver fibrosis.     

Preconcentration and separation of copper, nickel and zinc in aqueous samples by flame atomic absorption spectrometry after column solid-phase extraction onto MWCNTs impregnated with D2EHPA-TOPO mixture

A solid phase extraction method has been developed for the determination of copper, nickel and zinc ions in natural water samples. This method is based on the adsorption of copper, nickel and zinc on multiwalled carbon nanotubes (MWCNTs) impregnated with di-(2-ethyl hexyl phosphoric acid) (D2EHPA) and tri-n-octyl phosphine oxide (TOPO). The influence of parameters such as pH of the aqueous solution, amount of adsorbent, flow rates of the sample and eluent, matrix effects and D2EHPA-TOPO concentration have been investigated. Desorption studies have been carried out with 2 mol L(-1) HNO(3). The copper, nickel and zinc concentrations were determined by flame atomic absorption spectrometry. The results indicated that the maximum adsorption of copper, nickel and zinc is at pH 5.0 with 500 mg of MWCNTs. The detection limits by three sigma were 50 μg L(-1) for copper, 40 μg L(-1) for nickel and 60 μg L(-1) zinc. The highest enrichment factors were found to be 25. The adsorption capacity of MWCNTs-D2EHPA-TOPO was found to be 4.90 mg g(-1) for copper, 4.78 mg g(-1) for nickel and 4.82 mg g(-1) for zinc. The developed method was applied for the determination of copper, nickel and zinc in electroplating wastewater and real water sample with satisfactory results (R.S.D.'s <10%).     

Roman situlae from Conimbriga (Portugal): Compositional and microstructural characterization of anthropomorphic handle attachments

ABSTRACT

A collection of 33 anthropomorphic handle attachments of Roman situlae recovered from the archeological site of Conimbriga (Central Portugal, 2nd century BC–5th century AD) was studied by micro-Energy Dispersive X-Ray Fluorescence Spectrometry (micro-EDXRF), Scanning Electron Microscopy - Energy Dispersive Spectroscopy (SEM-EDS) and metallographic techniques. Regarding the characterization of Roman artifacts of regional production, the relation among typology, composition and microstructure was evaluated in order to infer the Roman influence on the copper metallurgy in Western Iberia. The collection was found to be heterogeneous, mainly constituted by leaded copper and leaded bronzes, with a wide range of lead contents. The artifacts were all produced by mold casting, and most of them show some post-casting processing. Important casting faults and broken artifacts were associated with higher lead contents, and were mainly leaded copper. The leaded bronzes were more carefully produced. The overall results suggest a local metallurgical tradition, with the usage of copper and copper alloy scraps, with high additions of lead. The aim was to produce colored (and cheaper) artifacts, without any major concerns about the finishing details.     

Penicillium digitatum immobilized on pumice stone as a new solid phase extractor for preconcentration and/or separation of trace metals in environmental samples

This study presents a column solid phase extraction procedure based on column biosorption of Cu(II), Zn(II) and Pb(II) ions on Penicillium digitatum immobilized on pumice stone. The analytes were determined by flame atomic absorption spectrometry (FAAS). The optimum conditions such as: pH values, amount of solid phase, elution solution and flow rate of sample solution were evaluated for the quantitative recovery of the analytes. The effect of interfering ions on the recovery of the analytes has also been investigated. The recoveries of copper, zinc and lead under the optimum conditions were found to be 97+/-2, 98+/-2 and 98+/-2%, respectively, at 95% confidence level. For the analytes, 50-fold preconcentration was obtained. The analytical detection limits for Cu(II), Zn(II) and Pb(II) were 1.8, 1.3 and 5.8 ng mL(-1), respectively. The proposed procedure was applied for the determination of copper, zinc and lead in dam water, waste water, spring water, parsley and carrot. The accuracy of the procedure was checked by determining copper, zinc and lead in standard reference tea samples (GBW-07605).     

Heavy metal removal from sediments by biosurfactants.

Batch washing experiments were used to evaluate the feasibility of using biosurfactants for the removal of heavy metals from sediments. Surfactin from Bacillus subtilis, rhamnolipids from Pseudomonas aeruginosa and sophorolipid from Torulopsis bombicola were evaluated using a metal-contaminated sediment (110mg/kg copper and 3300mg/kg zinc). A single washing with 0.5% rhamnolipid removed 65% of the copper and 18% of the zinc, whereas 4% sophorolipid removed 25% of the copper and 60% of the zinc. Surfactin was less effective, removing 15% of the copper and 6% of the zinc. The technique of ultrafiltration and zeta potential measurements were used to determine the mechanism of metal removal by the surfactants. It was then postulated that metal removal by the biosurfactants occurs through sorption of the surfactant on to the soil surface and complexation with the metal, detachment of the metal from the soil into the soil solution and hence association with surfactant micelles. Sequential extraction procedures were used on the sediment to determine the speciation of the heavy metals before and after surfactant washing. The carbonate and oxide fractions accounted for over 90% of the zinc present in the sediments. The organic fraction constituted over 70% of the copper. Sequential extraction of the sediments after washing with the various surfactants indicated that the biosurfactants, rhamnolipid and surfactin could remove the organically-bound copper and that the sophorolipid could remove the carbonate and oxide-bound zinc. Therefore, heavy metal removal from sediments is feasible and further research will be conducted.     

Cu/ZnO/LDPE纳米复合材料的离子释放及表面沉积物分析

为了降低含铜宫内节育器(Cu-IUD)引起的出血、疼痛和盆腔炎等副作用,本研究制备了新型的IUD用铜/氧化锌/低密度聚乙烯(Cu/ZnO/LDPE)纳米复合材料.并对复合材料的Cu2+和Zn2+释放行为,以及复合材料的表面特征进行了分析.结果表明,在释放初期阶段,纳米铜和纳米氧化锌含量的增加会抑制对方离子的释放;但在释放后期,则对对方离子的释放不产生显著影响.浸泡后的复合材料表面有大量沉积物,沉积物主要由CuO、Cu2(OH)3Cl、CaNa(H2PO4)3、CaZn(H2PO4)3和Zn4CO3(OH)6·H2O等成分组成.     

聚丙烯中空纤维膜/二(2-乙基已基)膦酸体系萃取水溶液中铜离子的研究

研究了聚丙烯中空纤维膜接触萃取器中二(2-乙基已基)磷酸萃取金属铜离子的工艺条件以及溶剂夹带,分析了原料的pH值、两相流速、有机相初始铜离子浓度以及萃取膜面积对萃取效率的影响,结果表明,两相流速、萃取膜面积对萃取率基本无影响,而水溶液的pH值和有机相初始铜离子浓度的改变使萃取率在40%～99%之间变化.这主要是由于整个萃取过程的传质阻力主要来源于D2EHPA和Cu2 的界面配位络合反应阻力,当铜浓度比较高时,传质阻力或传质系数与铜浓度无关,其值基本不变;而当铜浓度降低时,传质阻力随着铜浓度的降低而增大,传质系数则随着铜浓度的降低而减小.     

Elemental fractionation studies in laser ablation inductively coupled plasma mass spectrometry on laser-induced brass aerosols

Previous investigations on laser-induced aerosols of brass samples showed that preferential vaporization of zinc occurs during the ablation process leading to elemental fractionation and limited possibilities for non matrix matched calibration. In a variety of experiments carried out within this study it is shown that multiple effects are complicating the quantification of brass using IA-ICPMS. It is shown that the ablated copper and zinc is not homogeneously distributed within the laser-produced aerosol. Copper was found enriched up to 100% in particles larger than 100 nm as shown from EDX measurements (electron excited) on individual particles, and zinc was enriched by over 40% in the particles smaller than the lowest measurable particle size (below 100 nm or in the vapor phase). Solution nebulization analysis on digested filter-collected aerosols results in a higher Cu/Zn ratio than the certified value for the brass sample. ESEM pictures with analysis of the electron excited X-rays measured on the filter-collected material support the results showing copper enrichment. However, online LA-ICPMS measurements carried out under the same operating conditions as for filtering show a copper depletion within the ICP, which leads to the conclusion of partial vaporization and ionization of the aerosol particles in the ICP. The larger particles containing more or exclusively copper are not completely ionized. Within this study, three sources of elemental fractionation can be distinguished and described: (A) The ablation process leads to no measurable copper enrichment at the ablation crater rim. (B) Zinc deposition between the ablation site and the aerosol collection on filters leads to an up to 37% higher Cu/Zn ratio on the filter in comparison to the certified value. (C) On-line laser ablation aerosols measured within the ICPMS lead to significantly lower Cu/Zn ratios in comparison to the certified value. (D) Combination of the various studied sources of fractionation can finally lead to an agreement between measured and certified values due to inverse overlapping of various fractionation sources.