贵金属物理性质与原子结构的关系

按周期表位置排列的8个贵金属元素的物理性质,归纳出三种类型的规律,即原子半径相近,密度与比热接近倍比;熔点、沸点、硬度及其它力学性质呈线性变化;热导率和电导率呈不规则变化。文章用价键理论从原子结构特征对产生三类规律的原因进行了讨论。     

清洁高效的提取冶金--矿浆电解

环境污染和能源短缺是重有色金属冶炼的两大障碍。在对重有色金属湿法冶金存在主要问题进行分析的基础上研究成功的矿浆电解新技术,是一种清洁、高效的提取冶金。它具有流程短、能耗低、金属分离好和环境污染少等特点。矿浆电解的显著特点是充分利用了电积过程的阳极反应来浸出矿石,工艺能耗大大降低;在电解槽中硫化物转化为元素硫,而不产生硫酸,有利于环境保护。文章描述了国内外矿浆电解技术的发展过程及我国建立的世界上第一个矿浆电解工业生产厂的概况,指出我国在该领域处于世界领先地位和矿浆电解技术具有很好的前景。     

等离子束表面冶金技术冶金过程研究

研究了等离子束表面冶金技术的冶金过程,分析了冶金过程的特点.该过程是一个分阶段、连续过程;并研究了等离子表面冶金铁基合金的物理化学反应过程.最后得出等离子表面冶金过程的一般规律,用于指导该项技术的应用.     

探讨计算机在冶金自动化控制中的应用

当前我国冶金企业正在向着自动化的方向发展,计算机在此过程中发挥的作用越来越重要。本文主要介绍了当前我国冶金产业的发展状况,指出了其中的一些不足之处,并对计算机控制在冶金自动化控制中的应用进行了较为详细的叙述。     

贵金属检测实验室与一般化学检测实验室在管理中的区别

本文对贵金属检测实验室管理进行了探讨,指出了贵金属检测实验室在管理中与一般化学检测实验室的区别。     

冶金铸造起重机使用中的安全问题探讨

冶金起重机作为冶金行业安全、正常生产必不可少的关键和重要设备,其工作的可靠性、安全性、先进性一直受到人们的高度重视。本文笔者探讨了冶金铸造起重机使用中的安全问题。     

Discussion of an Enrichment Mechanism of Precious Metals by Base Metals and Mattes in Pyrometallurgical Processes

The enrichment mechanisms of precious metals by base metals or their mattes in pyrometallurgical processes are discussed at the atomic level in this paper. The reasons brought forward for a trace amount of precious metals to be trapped into base metals or mattes are that the melted slag phases possess different chemical structures and properties from that of the melted base metal or matte phases. As for the melted slag phase, its formation is thought to depend on the covalent bonds and the ionic bonds between Si, O atoms and Ca2+, Mg2+, Fe2+ ions to tie up each other. Because the bridging electrons in the slag phase are all thought as the localized electrons, the precious metal atoms are not stable among them. However, as for the metal phase, its formation is thought depend on the metal bonds to bind up the metal atoms. Because the electrons in the metal phases can move freely among the atoms, the precious metal atoms that enter the metal phase can cause the system’s free energy to decrease. For the melted mattes phase,because it has high electrical conductivities (between 103～104 s·cm-1) at higher temperatures, and its temperature coefficients presents the negative values, its conductance mechanism belongs with the electronic conduction. The property of the mattes is in fact similar to that of the metal at their melted state, so the precious metal atoms will enter the matte phase instead of the slag phase in a mattesmelting process.     

火法冶金中贱金属及锍捕集贵金属原理的讨论

从微观层次讨论火法熔炼过程中贱金属相及锍相捕集贵金属的原理。认为捕集作用的发生是由于熔 融的渣相和贱金属相两者的组成结构差异很大。渣相靠共价键和离子键把硅、氧原子和Ca２＋,Mg２＋,Fe２＋等离 子束缚在一起,键电子都是定域电子,贵金属原子在熔渣中不能稳定存在。金属相靠金属键把原子束缚在一起, 原子间的电子可以自由流动。贵金属原子进入金属相可降低体系自由能。锍在高温下具有相当高的导电率（数 值在１０３～１０４S·cm－１范围）,且温度系数呈负值,属电子导电。熔锍的性质类似金属,因此,在造锍熔炼过程 中,     

贵金属高温合金的研究现状及展望

简述了目前高温合金材料存在的问题,介绍了贵金属高温合金的主要特点,指出了研究贵金属高温合金的必要性,系统地综述了贵金属高温合金的研究成果、应用及目前存在的主要问题,最后展望了贵金属高温合金的研究方向。     

Application of Microwave Radiation to Extractive Metallurgy

In applying the microwave radiation to extractive me-tallurgy,it is essential first of all to find the extent ofmicrowave energy absorbed by various minerals experi-mentally.In this paper,more than 25 kinds of commonuseful minerals have been individually irradiated by a 500W,2450 MHz microwave source in an enclosed quartzcrucible to ascertain their heating temperature in a definitetime.In addition,the reduction and cbloridization testswere also carried out on the titanomagnetite concentrateand pentlandite with microwave heating,respectively.These experiments indicate potential applications of util-izing microwave energy in extractive metallurgy.     

Shape‐Controlled Synthesis of Colloidal Metal Nanocrystals by Replicating the Surface Atomic Structure on the Seed

Controlling the surface structure of metal nanocrystals while maximizing the utilization efficiency of the atoms is a subject of great importance. An emerging strategy that has captured the attention of many research groups involves the conformal deposition of one metal as an ultrathin shell (typically 1–6 atomic layers) onto the surface of a seed made of another metal and covered by a set of well‐defined facets. This approach forces the deposited metal to faithfully replicate the surface atomic structure of the seed while at the same time serving to minimize the usage of the deposited metal. Here, the recent progress in this area is discussed and analyzed by focusing on the synthetic and mechanistic requisites necessary for achieving surface atomic replication of precious metals. Other related methods are discussed, including the one‐pot synthesis, electrochemical deposition, and skin‐layer formation through thermal annealing. To close, some of the synergies that arise when the thickness of the deposited shell is decreased controllably down to a few atomic layers are highlighted, along with how the control of thickness can be used to uncover the optimal physicochemical properties necessary for boosting the performance toward a range of catalytic reactions.     

Microwave‐Assisted Rapid Synthesis of Graphene‐Supported Single Atomic Metals

Graphene‐supported single atomic metals (G‐SAMs) have recently attracted considerable research interest for their intriguing catalytic, electronic, and magnetic properties. The development of effective synthetic methodologies toward G‐SAMs with monodispersed metal atoms is vital for exploring their fundamental properties and potential applications. A convenient, rapid, and general strategy to synthesize a series of monodispersed atomic transition metals (for example, Co, Ni, Cu) embedded in nitrogen‐doped graphene by two‐second microwave (MW) heating the mixture of amine‐functionalized graphene oxide and metal salts is reported here. The MW heating is able to simultaneously induce the reduction of graphene oxide, the doping of nitrogen, and the incorporation of metal atoms into the graphene lattices in one simple step. The rapid MW process minimizes metal diffusion and aggregation to ensure exclusive single metal atom dispersion in graphene lattices. Electrochemical studies demonstrate that graphene‐supported Co atoms can function as highly active electrocatalysts toward the hydrogen evolution reaction. This MW‐assisted method provides a rapid and efficient avenue to supported metal atoms for wide ranges of applications.     

金属的密度与原子结构参数的关系

本文探讨了金属单质的密度与其原子结构参数的关系,得到了金属单质密度的计算公式对A_1、A_3型:ρ=2.93×10~5M/r~3met对A_2型:ρ=2.70×10~5M/r~3met理论计算结果与实验值相当吻合,说明我们的分析是正确的。     

Recent Progress in Engineering the Atomic and Electronic Structure of Electrocatalysts via Cation Exchange Reactions

In the past few decades, tremendous advances have been made in electrocatalysis due to the rational design of electrocatalysts at the nanoscale level. Further development requires engineering electrocatalysts at the atomic level, which is a grand challenge. Here, the recent advances in cation exchange strategy, which is a powerful tool for fine-tuning atomic structure of electrocatalysts via surface faceting, heteroatom doping, defects formation, and strain modulation, are the main focus. Proper atomic structure engineering effectively adjusts the electronic structure, and thus enhances the electronic conductivity and facilitates the adsorption/desorption of reaction intermediates. By virtue, the cation exchange strategy greatly boosts the intrinsic and apparent activities of electrocatalysts and shows a great potential toward design of new energy conversion devices, such as water splitting devices and metal–air batteries. It is believed that cation exchange offers new insights and opportunities for the rational design of a new generation of electrocatalysts.     

原子径向分布函数在材料结构研究中的应用

介绍了原子径向分布函数的基本理论,综述了原子径向分布函数在有机高分子材料、无机碳材料、金属材料等不同类型材料结构研究中的最新进展。阐明了原子径向分布函数相对于传统结构研究方法的特点和优势,并展望了该方法在碳纤维结构研究中的应用前景,该方法能够从原子级别揭示整个碳纤维制备过程中结构的演变规律,这对制备高性能碳纤维具有重要的指导作用。