低品位碳酸锰矿铵盐焙烧富锰工艺研究

研究了铵盐焙烧法处理低品位碳酸锰矿的工艺条件，确定最佳条件为：矿石：氯化铵：1：1～1．2，400-450℃焙烧60-90min。焙砂用60～90℃热水浸取10-20min，液固比为5：1～10：1，在此条件下，锰浸出率〉90％，浸出液经沉淀干燥后得到Mn〉50％的锰精矿。     

Effects of electrochemical doping of manganese dioxide with copper and lithium on the physicochemical properties

An electrochemical method has been used with fluoride electrolytes to synthesize specimens of manganese dioxide doped with copper and lithium. The compositions, structures, and physicochemical properties have been examined by chemical analysis and x-ray diffraction. It is found that the specimens have highly defective structures. Conclusions are drawn on the scope for using such products as electrode materials in chemical batteries and as catalysts based on manganese dioxide. __________ Translated from Poroshkovaya Metallurgiya, Nos. 3–4(448), pp. 62–66, March–April, 2006.     

用工业硫酸锰制取高纯碳酸锰的工艺研究

介绍了用工业硫酸锰制取高纯碳酸锰的工艺和操作条件，比较了不同的加料方式对碳酸锰产品质量及形态的影响。     

Fe-C-Mn-Al系TRIP钢两相区奥氏体转变模拟

为了研究Fe-C-Mn-A1系TRIP钢两相区奥氏体化过程中合金元素在奥氏体和铁素体中的分布,利用热膨胀仪、金相显微镜、电子探针等仪器,在对TRIP钢两相区奥氏体化过程进行热力学与动力学分析的基础上,建立了两相区奥氏体化过程的扩散模型,采用显式有限体积法对800℃与840℃的奥氏体化过程进行了数值求解.模拟结果表明:奥氏体转变初期受C元素在奥氏体中的扩散控制达到亚平衡,奥氏体转变速率较快;此时A1元素在奥氏体与铁素体界面处的浓度差较显著,Mn元素在奥氏体与铁素体界面处的浓度差不显著.奥氏体转变后期受Mn元素在铁素体内的扩散控制,转变速率较慢;此时A1元素在铁素体内已大量富集,Mn元素在奥氏体与铁索体界面处有较显著的浓度差.     

Development of Spectral Selective Multilayer Film for a Variable Emittance Device and Its Radiation Properties Measurements

A smart radiation device (SRD) that is a variable emittance radiator has been developed as a thermal control material for spacecraft. The SRD has the unique feature of large variation of the total hemispherical emittance _H near room temperature. The _H of the SRD changes depending on its temperature. However, there is a drawback of a large solar absorptance _S. It is too large to use as a thermal control material for spacecraft. In order to reduce the large _S, spectral selective multilayer film was developed. This multilayer film reflects solar radiation and transmits far-infrared radiation to maintain the variation in the _H of the SRD. This paper presents thermal radiative properties of the SRD with spectral selective multilayer film. The multilayer film was designed by using a genetic algorithm (GA). The designed multilayer film was evaporated on the surface of the SRD by the electron beam evaporation method. The experimental results of _S and _H of the SRD with the multilayer film agreed well with calculated results.     

W/O乳状液模板法制备纳米MnO2微球

以偏重亚硫酸钠（Na2S2O5）和高锰酸钾（KMnO4）为原料，通过W／O乳状液模板技术制备了纳米MnO2微球．用SEM、TEM、XRD、FT-IR等手段对产品的形貌、物相和成分进行了表征．结果发现用本方法制得的纳米MnO2微球，大小基本均匀，球形规整，纯度较高，且具有较高的反应活性．结合实验事实和产品特性，初步探讨了纳米MnO2微球的形成机理．     

介孔硅酸锰镁可充镁电池正极材料的制备及其电化学性能研究

采用介孔二氧化硅MCM-41作模板和硅源, 合成了具有介孔结构的可充镁电池正极材料硅酸锰镁. 分别用XRD、SEM、TEM和氮气吸脱附测试研究了合成材料的介孔结构, 并通过循环伏安、恒电流充放电测试比较了介孔与无孔硅酸锰镁材料的电化学性能. 由于介孔材料活性表面较大, 可增加电解液与活性材料的接触, 使材料具有较多的电化学反应位. 因而, 与相应的无孔材料相比, 具有介孔结构的硅酸锰镁材料呈现出较低的充放电极化、较大的放电容量和较高的放电电压平台. 在0.25 mol/L Mg(AlCl₂EtBu)₂/THF 电解液中, 0.2 C(约62.8 mA/g)充放电速率下, 介孔硅酸锰镁材料首次放电容量可达到241.8 mAh/g, 放电平台为1.65 V ( vs Mg/Mg²⁺). 设计具有介孔结构的材料为提高可充镁电池正极的电化学性能提供了一条有效的途径.     

Early-stage nucleation of manganese sulfide particle and its processing evolution in Fe—3wt.%Si alloys

Manganese sulfide is often referred to as one of important inhibitors in grain-oriented electrical steels, which is of great importance to yield strong Goss texture. However, the early stage of nucleation for such inhibitors and their evolution during the processing has not been well understood. In present work we selected a Fe--3.12wt.%Si--0.11wt.%Mn--0.021wt.%S model system and used FE-SEM and atom probe tomography (APT) to investigate the precipitation behavior of MnS inhibitors at near atomic scale. It was found that the Si--S enriched clusters with sizes of 5--15 nm were formed close to the MnS particles. The density of inhibitors decreased after large pseudo-plane-strain compression because of the effect of dislocation motion, and then slightly increased again when sample was aged at 200°C for 48 h. The dislocations and grain boundaries can act as fast diffusion paths and assist the reemergence of Si--S enriched clusters.     

Ti/SnO2+SbOx/MnO2(Ce)电极制备及性能表征

采用热分解法制备了不同浓度稀土元素铈掺杂钛基二氧化锰电极,通过SEM、极化曲线和EIS测试等方法分析了自制电极的形貌、催化性能和废水处理效果等.结果表明:适量铈元素的掺杂能改善二氧化锰电极的表面形貌,提高电极的析氯电催化活性,增强电极的耐蚀性和稳定性;使其在氯化钠电解质体系中处理亚甲基蓝印染废水的色度去除率达到96.9％,COD去除率达到91.8％.     

Yolk–Shell MnO@ZnMn2O4/N–C Nanorods Derived from α‐MnO2/ZIF‐8 as Anode Materials for Lithium Ion Batteries

Manganese oxides (MnO_x) are promising anode materials for lithium ion batteries, but they generally exhibit mediocre performances due to intrinsic low ionic conductivity, high polarization, and poor stability. Herein, yolk–shell nanorods comprising of nitrogen‐doped carbon (N–C) coating on manganese monoxide (MnO) coupled with zinc manganate (ZnMn₂O₄) nanoparticles are manufactured via one‐step carbonization of α‐MnO₂/ZIF‐8 precursors. When evaluated as anodes for lithium ion batteries, MnO@ZnMn₂O₄/N–C exhibits an reversible capacity of 803 mAh g^?1 at 50 mA g^?1 after 100 cycles, excellent cyclability with a capacity of 595 mAh g^?1 at 1000 mAg^?1 after 200 cycles, as well as better rate capability compared with those non‐N–C shelled manganese oxides (MnO_x). The outstanding electrochemical performance is attributed to the unique yolk–shell nanorod structure, the coating effect of N–C and nanoscale size.