Evaluation of surface/interface quality,microstructure and mechanical properties of hybrid additive-subtractive aluminium parts

A disadvantage of selective laser melting (SLM) processes for the manufacture of large parts is their slow build time per unit volume. A hybrid route is to generate core simple shapes traditionally, for example by machining, followed by adding final features by SLM. Here the mechanical integrity of such hybrid parts is studied, choosing the building of AlSi10Mg by SLM on a machined AA6082 base, in the shape of a tensile test piece, as a simple example. These materials are chosen for their relevance to lightweight parts. As-built parts fail at the SLM/machined interface but standard heat treatments transfer failures to the machined material. Optimised SLM processing conditions and microstructures of the SLM and interfacial regions are reported.     

河南郭家岭金矿原生晕特征及深部找矿预测

河南郭家岭金矿床位于华北陆块南缘褶皱带多金属成矿带与北秦岭多金属成矿带交界处。文章结合矿区地质背景、矿床成因、矿体特征及钻孔岩石地球化学采样分析,系统地研究了矿床深部的原生晕地球化学特征。地球化学原生晕统计分析表明,郭家岭金矿区矿化普遍高于区域背景值,Au、Ag、Cu、Mo、Sn、W、Zn、Sb、Bi 9种元素的富集系数较大。通过R型聚类分析,表明钻孔内元素间相关性较好,与Au相关性最强的元素为Bi,并且As、Sb、Zn元素组合异常强烈,而W、Mo元素组合异常较弱,表明该金矿床属于高温热液矿床,处在原生晕的前缘;从钻孔原生晕空间分布看,原生晕异常现象明显,矿化较好,与Ag、Cu、Pb元素有较强的相关性,表明该金矿床处在异常前缘或者异常中上部。     

形式源于功能——北航新主楼的建设理念

从北航新主楼的设计理念出发,重点介绍了大楼的总体布局、使用功能、智能控制、环保节能等,并从发展教育、促进科研、文化交流等方面分析该建筑的建设理念。     

高校校园公共空间探析

高校学生特定的心理及学生生活与行动的群体特性决定了公共空间在高校规划中的重要性。从市场经济与“服务育人”理念出发,指出校园公共空间现状存在公共空间缺失、“失落空间”过多、公共空间不适应的问题,应创造向心空间、交往的文化空间以及心灵空间。     

从读书行为到信息交流--南昌大学图文信息中心设计

本文回顾了南昌大学图文信息中心的设计过程。通过对项目背景、总图关系、功能空间形态、建筑形态等方面的介绍,探讨了当代高校图书馆的内涵和外延所发生的一些新的变化,指出了从读书行为到信息交流的转变是促使图书馆新形态产生的直接原动力。     

Heavy metals in aquatic plants,clams, and sediments from the Chesapeake Bay,U.S.A. implications for waterfowl

Dry weight concentrations of cadmium, lead, copper and zinc were measured in clams, submerged aquatic macrophytes and sediments from several locations in the Chesapeake Bay region. Clam species included Macoma balthica, Mya arenaria, and Rangia cuneata; plant taxa included Najas spp., Potamogeton spp., Ruppia maritima, Vallisneria americana, and Zostera marina. Cadmium and lead concentrations were generally greater in whole plants than in soft tissues of clams, while the reverse was true for zinc; no marked trend was observed in copper concentrations. These results suggest that the changes occurring in the food habits of some Chesapeake Bay waterfowl towards increased clam utilization as a result of declining submerged plant abundances is not increasing ingestion of the nonessential metals cadmium and lead. Highest lead, copper and zinc concentrations were observed in sediments from the Patapsco River, which is probably due to the proximity of Baltimore Harbor. Highest cadmium concentrations were observed in sediments in the Port Tobacco River, a tributary of the Potomac River. These observations were generally consistent with high concentrations of the respective metal(s) in biota from these locations. Concentrations of the four metals in sediments were highly correlated to organic matter content.     

山东大学新校区环境设计

从空间分析的角度介绍山东大学新校区景观规划设计的构思,引申出对校园空间格局的探讨,为今后更好地从人文主义出发,创造宜人化的生活环境尺度提供借鉴.     

清华大学“景观规划设计”硕士研究生设计课程评述

对清华大学“景观规划设计”硕士研究生课程的主要内容和特点进行了综合评述。针对以Studio为核心的教学模式,介绍了三个系列Studio的课程内容,对设计课的课程设置、师资力量、课程选题和组织方式等方面的特点进行了重点阐述。     

50年艰辛创业 新世纪再创辉煌——贺同济大学城市规划专业成立50周年

195 2年全国高等院校院系调整 ,同济大学在原有的土木工程基础上 ,综合了上海及长江三角洲各高等院校的建筑学专业 ,成立了建筑系。当时金经昌先生留德 8年于 194 6年回国后 ,从 194 7年起在同济大学开设了都市计划和都市工程设计课程 ,在此基础上 ,金经昌先生与冯纪忠先生鉴于建筑学科的发展趋势 ,考虑今后大规模建设的需要 ,力主在建筑系内创办城市规划专业。专业创建之时 ,虽采用的是前苏联专业目录中的“都市建筑与经营”的专业名称 ,但在教学计划中根据中国的国情和城市规划专业学科本身的知识结构对课程设置加以修改 ,把目标定位在培…     

英国剑桥大学建筑系的科研与研究生教学

介绍了剑桥大学建筑系的主要科研内容及研究生培养的情况。