龙滩水电站大坝混凝土供料线的优化设计

龙滩水电站大坝为碾压混凝土重力坝，大坝混凝土总量约580万m^3，其中碾压混凝土约362万m^3，每条混凝土供料线的平均输送能力为300m^3／h，是水电工程之最。龙滩大坝混凝土供料线系统由拌和楼出料皮带机和系统连接皮带机、3条高速皮带机供料线、3条负压溜槽和2台塔式布料机组成。如何保证混凝土在运输过程中的均匀性及和易性，尽量缩短运输时间，减少倒运次数，保证人仓强度，是混凝土供料线系统布置、设计的重点。     

关于砂金工艺矿物学研究规范化的建议

本文从样品的采集、加工、制备到砂金性状、矿砂物质组成;从分离、鉴定质量要求到选矿产品考察;从矿砂可洗性、可选性评价到矿砂工艺类型确定等项内容的系统化、标准化,阐述了砂金工艺矿物学的研究规范。     

Review of Operating Experience Of Ozone Systems In Municipal Plants In The United States

The treatment chemical ozone has now been successfully used in the United States in municipal water and wastewater plants for many years. To insure continuous, successful operations of these applications, operating obstacles had to be dealt with and overcome.

In this paper, examples of field operating problems and their solutions are described. The experiences at specific municipal water and wastewater installations are reviewed in detail. Discussed for each example are : the background and effects of the problem, the problem-solving process, and the eventual resolution of the problem. The examples include simple unit operations to entire processes.

By observing the ozone installation's operation several years after start-up, the design of future ozone systems can be improved and operating problems minimized.     

勘查砂金的最新技术KJ法

本文介绍了朝鲜民主主义人民共和国金策工业大学金致崇教授发明的根据磁场调查勘查砂金的最新技术(简称KJ法)。这项技术是不用钻探和井探,而只用仪器探出砂金的矿体形状、大小、埋深及品位。     

Where to for Brazil's Cities? Citizen Empowerment or Global Marketing?

An awakening interest in public space in Brazilian cities is emphasising the value of existing civic areas. Guilherme Wisnik , a critic, curator and professor at the Faculty of Architecture and Urbanism of the University of São Paulo, looks at the history and potential future of Brazil's urban spaces. He highlights how despite the introduction of innovative Modernist design in the mid-20th century, which forged ‘a new relationship between architecture, urbanism and landscape design’, more recently the country's cities have been subject to the vicissitudes of market and political forces.     

长江口水域砂矿资源及其合理开发利用

长江河口地区水下砂体发育形成了良好的砂矿资源,具有开发利用前景.分析砂矿资源的分布特点、沉积规律与物质组成,探讨合理利用的途径及其开发过程中须注意的环境地质问题.水域砂矿资源可为长江口岸带经济圈的基础建设与土地增殖提供重要物质来源.     

电感耦合等离子体质谱法测定砂金中稀土元素

建立了砂金中15种稀土元素的电感耦合等离子体质谱测定方法。考察了基体Au的谱线干扰及基体效应,采用In内标补偿基体对待测信号的抑制作用。仪器检测限为0.000 9～0.002 9μg/L,加入标准物质的回收率为98%～106.7%,分析结果的相对标准偏差（RSD）为0.33%～1.79%。该方法简单、快速、灵敏、准确。     

中国南方岩溶砂锡矿的分布

岩溶砂锡矿是中国南方第四纪沉积物中的一种重要矿床类型,具有矿层厚、品位高、工业价值大等特点。本文介绍了中国南方岩溶砂锡矿的分布规律、主要矿床类型,并指出了该区的找矿方向。     

Instrumental neutron activation analysis of beachrock samples of South East Coast of Tamilnadu, India

Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values.