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relaxation process of the supercooled and glassy Pb, and the metastable bcc phase plays an important role in the precursor of crystallization. Key words: supercooling liquid; amorphous metal Pb; isothermal... the formation and evolution characteristics of bcc phase during the isothermal relaxation processes of supercooled liquid and amorphous metal Pb, by using molecular dynamics method, and adopting the cluster-type......
in molten salt can promote the interdiffusion of Al, Pb and Sn on the interface, and the combination strength can exceed 2.1 MPa. The metal bath procedure after electroless plating can mend the holes of the film, and a compact and composition adjustable Pb alloy film can be obtained on Al substrate. Key words: molten salt; electroless plating; Al substrate; Pb film; combination strength; metal bath 金......
of brewing industry, was used to prepare an efficient heavy metal adsorbent using one-step and fast esterification method. The adsorption behaviors, adsorption kinetics and mechanism of Pb(Ⅱ) by esterified...重金属吸附剂.本文作者开发了一步快速酯化改性麦糟新方法[8],优选次亚磷酸钠(NaH2PO2·H2O)为催化剂,N, N-二甲基甲酰胺(DMF)为反应介质,以柠檬酸与麦糟反应2 h即制备了高效的重金属吸附剂酯化改性麦糟,可用于吸附Pb(Ⅱ).本文对酯化改性麦糟吸附Pb(Ⅱ)的吸附特性,吸附动力学以及吸附机制进行系统研究,为反应器的设计和运行提供基础信息,对含铅废水处理具有重要实际意义. 1......
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在热力学平衡时是晶态结构, 有固定的熔点. 3) Pb纳米薄膜的熔化开始温度低于熔化结束温度; 熔化从表面开始, 并逐渐趋近于薄膜中心, 这不同于纳米微粒的先表面熔化而后内部瞬间熔化过程. REFERENCES [1]Takagi M. Electron-diffraction study of liquid-solid transition of thin metal films[J... 文章编号: 1004-0609(2006)07-1161-05 铅纳米薄膜熔化温度尺寸效应的分子动力学研究 齐卫宏1, 2, 汪明朴2 (1. 江苏大学 材料科学与工程学院, 镇江 212013; 2. 中南大学 材料科学与工程学院, 长沙 410083) 摘 要: 利用紧束缚分子动力学的方法研究厚度为0.5~10.4nm自由表面铅纳米薄膜的熔化温......
that it is practically feasible to produce pure Pb metal by electrochemical reduction of PbCl2 in eutectic NaCl-KCl melts, and has provided important fundamental for the further study on lead recovery from... differences in the formation of various metal chlorides [10-13]. The Pb-bearing phases in spent LABs can be readily converted to PbCl2 by chlorination roasting at a relatively low temperature [1,14......
文章编号:1004-0609(2012)09-2667-09 耐铅产絮克雷伯氏菌胞外聚合物EPS-07 吸附水中Pb(Ⅱ)的特性 信 欣,姚 力,崔钶,叶芝祥,羊依金,余 静 (成都信息工程学院 资源环境学院,成都 610225) 摘 要:研究抗铅产絮菌株B-07胞外聚合物EPS-07作为吸附剂处理含Pb(Ⅱ)的废水的吸附性能.结果表明:当吸附时间为80 min,pH为5.5,吸附剂用量为0.8 g/L,溶液中Pb(Ⅱ)初始浓度为50 mg/L时,EPS-07对铅离子的吸附平衡容量为61.5 mg/g.吸附等温式能较好地用Langmuir模型表达,吸附动力学很好地符合准二级动力学模型.FT-IR结果表明,EPS-07与Pb(Ⅱ)的作用过程中,主要是羟基,羧基等基团参与了吸附作用.SEM观察显示EPS-07表面结构......
2可见,在两组焊接参数条件下,焊核区均未观察到明显的宏观缺陷,得到了完整形状的焊核区.同时,焊核均为盆状形貌,但上部轴肩影响区域深度较浅,主要为搅拌针影响区.这一现象明显有别于铝合金,表明在铅合金的FSW过程中,轴肩对焊核上部材料的作用能力相对较小.这应该是由于铅的熔点较低,在摩擦热作用下,生温后软化明显,使材料不能紧跟轴肩,因此轴肩带动的材料塑变区域很小. 图1 Pb-Sn合金轧板... macrostructures of FSW joints of rolled Pb-Sn alloy plates (SZ-Stir zone; HAZ-Heat affected zone) 2.2 工艺参数对焊缝性能的影响 由于铅合金的密度大,但强度往往却很低,在实际生产应用中容易变形导致短路,易造成安全事故,因此铅合金焊缝的力学性能是评判阳极板性能好坏的极其重要的参数之一[11]. 图3所示为在两......
supplied a minority of ore lead. The ore deposit should be the result of the crust-mantle interaction and maybe had been formed in the orogenic environment. Key words: Pb isotope; ore source; tectonic...-forming elements, ore-bearing layer [4]. In the west ore belt, the ore-bearing layer is the middle and upper Devonian and the main mineralized elements consist of Sn, Pb, Zn, Sb and Ag. Yet......
area 表3 灯影组,陡山沱组金属硫化物与中国大陆,全球平均铅同位素μ和κ对比 Table 3 μ and κ of Pb isotope compositions in China continent,global mean and metal sulfides of Dengying formation and Doushantuo formation 5... the upper crust and the Orogenic, and there is a significant positive correlation between them, which indicates that Pb of the metal sulfides in Dengying formation can be derived from a mantle-crust......