New Directions in Concrete Health Monitoring Technology

The NSF-sponsored Center for Advanced Cement-Based Materials is actively involved in research aimed at the development of technologies for health monitoring and nondestructive evaluation of the concrete infrastructure. This paper summarizes pertinent research performed at the center. Basic findings from several new laboratory-based nondestructive evaluation techniques for concrete are reported. The described techniques are based on measurements of mechanical waves that propagate in the concrete. First, ultrasonic longitudinal wave (also called the L-wave or P-wave) signal transmission (attenuation) measurements are shown to be sensitive to the presence of damage in the form of distributed cracking in concrete. Next, experimental procedures that enable practical one-sided wave signal transmission measurements to be performed on concrete structures are described. The utility of the signal transmission measurement is demonstrated by two experimental test series; the depths of surface-opening cracks in concrete slabs are estimated and the extent and nature of autogenous healing in concrete disks are studied. Finally, an approach by which fatigue-induced damage in concrete structures is nondestructively monitored is described. Vibration frequencies are shown to be sensitive to the presence of fatigue-induced cracking in concrete specimens; changes in the vibration frequency of a concrete specimen during fatigue tests are related to the remaining fatigue life of the test specimens.     

新型高强耐磨复杂黄铜及其生产技术

以β相为基的高强耐磨多元复杂黄铜是新近发展起来的并得到广泛应用的新型高技术含量、高附加值的铜合金品种，具有广阔的市场发展空间。本文系统地阐述了具有市场需求前景的高强耐磨复杂黄铜的种类及特性，重点介绍了典型合金产品的生产加工技术，希望对该类合金的生产及新品种的开发起到建设性的指导作用。     

废旧氢镍电池回收处理技术研究进展

目前废旧氢镍电池的回收处理是能源材料再利用的重要内容之一.本文对氢镍电池的化学组成、工作原理以及废旧氢镍电池的回收处理方法进行了评述,阐述了废旧氢镍电池处理技术的研究现状.废旧氢镍电池的主要回收处理方法是采用火法冶金、湿法冶金、正负极分开处理三种回收处理技术,本文同时介绍了一种新的废旧氢镍电池回收处理技术,并就当前废旧氢镍电池回收处理研究中存在的问题提出了相关建议.     

退役磷酸铁锂电池回收技术综述

近年来,我国新能源汽车及储能领域快速发展,磷酸铁锂电池使用量井喷式上升。在未来会产生大量退役磷酸铁锂电池,对其进行回收不仅可以缓解国内锂资源紧缺的问题也能减少含氟电解液带来的环境污染。回顾了近年来国内外退役磷酸铁锂电池回收技术,包括电池预处理、磷酸铁锂正极废料修复、全浸出回收、选择性提锂及提锂尾渣的回收等,总结归纳了各技术最新的研究成果,从工艺的经济性、回收率、环境影响等方面,对各个工艺的优缺点进行分析,并展望了未来退役磷酸铁锂电池回收技术的发展方向。     

报废三元锂电池的绿色短流程再生技术

国家“双碳”战略的实施需要绿色创新技术的支持。综合运用元素分析、ICP-OES等方法分析退役三元锂电池中黑粉的成分;通过吉布斯自由能和饱和蒸气压分析,论证了真空碳还原法回收Li和去除Al的可行性。真空碳还原试验结果表明,在550℃可以回收98.17%的Li,在850℃可去除98.21%的Al;通过氧化焙烧方式,在750℃可去除100%的C,最终得到三元前驱体。     

新农村建设进程监测及其动态类型——以岱岳区为例

在新农村建设水平评价的基础上,提出了新农村建设进程动态监测的方法和动态类型划分方法,并在泰安市岱岳区进行了实证.结果表明,研究方法可行,结果对当地新农村建设有实际指导意义.     

Review of Autism: New Directions in Research and Education.

Reviews the book, Autism: New Directions in Research and Education by Christopher D. Webster, M. Mary Konstantareas, Joel Oxman, and Judith E. Mack ( 1980). Autism: New Directions in Research and Education is an important and often intriguing collection of formal and informal papers presenting a view of autism as a severe, extensive and perhaps particular communication disorder. Of the twenty-five papers included in the volume, only three were not written by one of the four editors as at least a co-author. While this factor undoubtedly adds to the cumulative power of the volume, it may also have influenced the inclusion of several general papers, such as how to write a scientific report, which are only tangentially related to the specialty topic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

两种新型铝合金建筑型材及其加工技术

本文介绍了两种新型铝合金建筑型材(灌注PU树脂隔热铝型材、穿条隔热铝型材)的生产技术和工艺参数。     

从废旧三元锂离子电池中回收有价金属的新工艺研究

废旧三元锂离子电池经过放电、焙烧、破碎、筛分等预处理方法分离出电池活性物质、集流体与钢壳,再采用H2SO4-Na2SO3对废电池粉料（活性物质）进行浸出,浸出液调节pH至4.5,过滤以除去铁和铝,滤液再调pH至11左右,将锂和镍钴锰分离,得到的锂液经过浓缩后加入Na2CO3得到工业级的LiCO3,在镍钴锰富集物中加入氨水将锰和镍钴分离,最后使用P507分离镍和钴,在相比O/A=1,平衡pH=4.5,有机相组成为25% P507 75%溶剂油,经二级逆流萃取后钴的萃取率为99.3%。使用200 g/L硫酸为反萃剂,相比为5时,钴的回收率达99.21%。反萃液使用草酸铵沉钴,萃余液中的镍采用氢氧化钠沉淀,整个工艺流程中钴的回收率为91.82%,镍的回收率为91.12%。