Mg-6Al-1Nd-1.5Gd合金的高温蠕变机制

采用高温蠕变装置,研究了Mg-6Al-1Nd-1.5Gd合金在150、175、200℃以及50、70、90 MPa条件下的高温压缩蠕变行为,分析合金在高温蠕变过程中的蠕变机制。结果表明,Mg-6Al-1Nd-1.5Gd合金的平均应力指数及蠕变激活能分别为4.64和73.87kJ/mol,其主要蠕变机制是由位错攀移和晶界扩散共同作用,合金的蠕变本构方程为:ε=1.877×10-8σ4.641exp[-73 865/(RT)];合金在高温蠕变过程中,微观组织中的位错密度逐渐增大,出现位错缠结及位错堆积,合金蠕变后的晶粒变得粗大,金属间化合物Al3Nd和Al3Gd在晶界上出现偏聚。     

Hierarchical porous onion-shaped LiMn<Subscript>2</Subscript>O<Subscript>4</Subscript> as ultrahigh-rate cathode material for lithium ion batteries

Spinel LiMn₂O₄ is a widely utilized cathode material for Li-ion batteries. However, its applications are limited by its poor energy density and power density. Herein, a novel hierarchical porous onion-like LiMn₂O₄(LMO) was prepared to shorten the Li⁺ diffusion pathway with the presence of uniform pores and nanosized primary particles. The growth mechanism of the porous onion-like LiMn₂O₄ was analyzed to control the morphology and the crystal structure so that it forms a polyhedral crystal structure with reduced Mn dissolution. In addition, graphene was added to the cathode (LiMn₂O₄/graphene) to enhance the electronic conductivity. The synthesized LiMn₂O₄/graphene exhibited an ultrahigh-rate performance of 110.4 mAh·g^–1 at 50 C and an outstanding energy density at a high power density, maintaining 379.4 Wh·kg^–1 at 25,293 W·kg^–1. Besides, it shows durable stability, with only 0.02% decrease in the capacity per cycle at 10 C. Furthermore, the (LiMn₂O₄/graphene)/graphite full-cell exhibited a high discharge capacity. This work provides a promising method for the preparation of outstanding, integrated cathodes for potential applications in lithium ion batteries.

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甘肃省肃北县二段井地区遥感地质特征及金多金属找矿预测

甘肃省肃北县二段井地区属于北山造山带南带拾金坡-金场沟金、铜、铁和铅锌、银、稀有金属成矿带,具有良好的成矿条件和找矿潜力.该文利用日本ALOS遥感数据,完成遥感地质解译工作,采用美国Land-sat 8 OLI数据完成矿化蚀变信息的提取工作,并结合已有的地质矿产及物化探资料,对区内的成矿地质条件及找矿远景进行了分析预测...     

连续结晶器积垢的化学清洗

通过对连续结晶器积垢成因的分析,提出了用纯碱和氯化钠溶液清洗的新方法．     

虚拟局域网(VLAN)管理软件设计与实现

VLAN是交换机的一个重要功能，它使交换机能够在第二层控制广播的传送，并划分逻辑子网，本文给出了利用SNMP技术来实现VLAN管理软件的方法，系统地描述了用SNMP＋＋从交换机中读取，处理MIB对象值的过程，它能在Windows95/NT,VC 6.0,WinSNMP2.0以及Linux/Unix,GNUC ,SNMP＋＋for Unix平台上运行，这对进一步开发自己的网络管理软件提供了思路。     

一种控制系统串行口驱动程序的实现

控制系统中的通信是设计人员经常需要面对的问题,本文介绍了一种工业控制系统中串行口驱动程序的设计与实现。     

SOFTDOCK: understanding of molecular recognition through a systematic docking study

Molecular recognition and docking are essential to the biologicalfunctions of proteins. SOFTDOCK was one of the first moleculardocking methods developed for protein–protein docking.Its ability to represent the molecular surface with differentshapes and properties and to dock a variety of molecular complexeswith certain conformational changes was demonstrated in a previousstudy. In the present work, we studied the effects of the dockingparameters through statistical analysis. Seventy one typicalbinary complexes of different categories in PDB were also systematicallydocked for a test; 57 of them produced correct solutions withone set of docking parameters whereas the other 14 complexesrequired adjustment of the docking parameters, by decreasingthe softness of the recognition and hence the background noise.We found that these 14 complexes had special structural features.Our results suggest that a variety of mechanisms may be involvedin molecular recognition rather than the shape complementarityonly, which is very helpful in developing more powerful methodsfor predicting molecular recognition.     

大型惯性圆锥破碎机在金属矿山的应用

分析了ＫИД－２２００惯性圆锥破碎机在杰兹卡尔兹甘矿的应用情况，总结了利用惯性圆锥破碎机替代传统圆锥破碎机的优点，并结合我国金属矿山的现状，提出了利用惯性圆锥破碎机改造选矿厂的技术方案。     

用DSC法研究形状记忆合金的热稳定性

用DSC法对粉冶法制得的Cu-15.39wt％Al-4.13wt％Ni形状记忆合金的热稳定性进行了研究,结果表明,其Ms在进行了10次热循环后开始稳定在140～200℃之间,合金有良好的热稳定性。     

景观公正的研究进展与多维评价方法 探究

随着社会发展,城镇化进入转型时期,关于城市发展中社会公正的讨论越来越多,从景观视角来保障社会公正是风景园林师当下的责任。景观公正是指对于绿地资源的合理分配、使用、管理和运营,不论使用者的社会地位高低,让他们平等地享有景观权利与担负景观义务,其核心是景观层面上的平等正义。梳理了国内外景观公正的发展与研究进展,厘清景观公正的定义与内涵,总结景观公正的分配公正、过程公正和互动公正3个维度的应用场景与评价方法,对未来景观公正的建设内容提出了展望和建议。