全球铬矿石资源国对中国供应安全度分析

近年来,中国铬矿石年均进口量维持在1 000万t的高位,我国目前主要铬资源进口国为南非、哈萨克斯坦、印度、阿尔巴尼亚、土耳其、伊朗六国,2017年这六国对我国供应占比分别为72.3%、8%、3.4%、2.1%、1%、0.6%;政治因素、资源量和产量会成为影响我国铬矿资源稳定供应的主要因素。本文分析了六国的储量、产量、对华出口量、运输距离及地缘政治的情况,利用决定系数和多样性指数建立模型并进行定量分析,得出我国未来铬矿石进口国优先顺序依次为南非、哈萨克斯坦、印度、阿尔巴尼亚、土耳其、伊朗。该模型未将突发事件的影响列入考虑,结果只适用于当前政治经济局势环境中。根据上述结果,提出我国未来应保持与南非、哈萨克斯坦两国的贸易合作并探索与其他国家进行更进一步合作的资源配置方案,在全球铬矿生产国进行投资建厂、完善全球铬矿资源布局;并提出了未来10～15年我国铬矿布局建议,控制全球产能15%;主要规划产能分布在南非、伊朗、阿曼、哈萨克斯坦四国。     

探水注浆工作在北洺河铁矿的实践

通过北氵名河铁矿基建过程中探水注浆的实践 ,提出采用探水注浆方法通过风化蚀变严重、裂隙岩溶发育 ,且被泥沙充填复杂地层的技术措施 ,并对有关参数及注浆结束标准进行探讨     

电击防护基础安全标准综述

依据IEC基础安全标准和出版物,概述了用于电子设备与电击防护有关的基础安全标准的主要内容,并把各个独立发布出版的标准中的内容有机地联系组合起来,形成一个较为系统和完整的电击防护理论体系.     

包钢高级技校电气工程专业教改初探

介绍了现代电气技术发展的特点及现代企业对操作者技能要求的新趋势,通过对包钢二级厂矿选人用人标准的分析,对包钢高级技校电气专业教学改革提出建议。     

居住小区不因市场而失效——小区理论在市场机制下的理解与应用

"居住小区"一词虽然产生于计划经济,但与邻里单位是同一概念,都是工业化和城市现代化的产物,是不依政治经济体制而变化的客观需要。随着我国经济制度的逐步转型和市场化发展,居住区建设模式发生根本改变,小区理论以及技术标准受到诸多质疑。本文试图从小区理论的产生、与邻里单位的关系、国内外实践入手,阐述居住小区理论并未因市场化而失效,进而针对如何在市场条件下运用居住区基本原理提出相应的建议。     

对宣贯ISO9000族标准若干问题的探讨

本文根据作者学习ISO9000族标准的体会,对质量体系、质量保证体系、ISO9000的推动方式、质量体系认证等问题进行探讨,并提出了贯彻ISO9000族标准的几点意见。     

Assessment of wind load factors for hurricane-prone regions

We study the issue of whether the wind load factors specified in the ASCE 7–95 Standard for hurricane- prone regions on the one hand and extratropical storm regions on the other are mutually consistent with respect to risk. We consider structures or elements whose design is governed by wind loads and for which wind directionality effects are not significant. We present estimates according to which ASCE 7–95 Standard provisions for wind loads inducing the design strength result in (1) safety levels that are considerably lower for hurricane-prone than for extratropical storm regions, and (2) estimates of mean recurrence intervals of hurricane wind loads inducing the design strength of about 500 y if epistemic uncertainties are neglected, and significantly lower than 500 years otherwise.     

Water Quality for Renal Dialysis

Over 100000 renal failure patients are treated by dialysis in the European Community (EC), and the number is rapidly increasing due to better medical care. The full importance of the quality of water used for renal dialysis is only now being recognized. Aluminium intoxication, first described in the early 1970s, highlighted the need for adequate treatment of water used to prepare dialysate. Other materials harmful to dialysis patients, such as chloramines, may arise as a result of water treatment practice. The paper presents a European-wide assessment of the problems of trace contaminants in dialysis feed water, and examines some contaminant sources in mains water in the light of dialysis water standards and the current treatment techniques available.     

Impact in Scotland of UK and EC Sewage Legislation

The EC Directive (91/271/EEC) concerning urban waste water treatment has far-reaching financial and technological implications for local authorities in Scotland which are responsible for sewerage. Increased capital consent limits and additional financial assistance from central government are essential if the requirements of the legislation are to be met.
Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.
The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public.     

Waste Stabilization Ponds: A Viable Alternative for Small Community Treatment Systems

Waste stabilization ponds are widely used in many European countries, such as France and Germany, for the treatment of wastewater from mainly small communities. There would seem to be no reason why they should not also be a suitable treatment process for populations of under 2000 in the UK. The relative advantages and disadvantages of ponds are compared to other small community treatment systems, such as rotary biological contactors, biological filters and reed-bed systems, particularly in relation to effluent standards with respect to algae, nutrient removal and relative costs.