南水北调中线工程战略环境影响评价探讨

根据南水北调中线工程的特点,从宏观性、全局性、综合性和协调性提出了环境评价指标体系。研究和评价了中线工程对我国可持续发展战略影响、水资源优化配置与可持续利用、增强综合国力和地区竞争力、促进京津华北地区可持续发展战略问题。进行了中线工程对宏观经济、区域经济发展,社会公平、城市化进程、改善生活质量等社会发展,以及水环境保护、生态完整性与重要敏感生态问题、移民与可持续发展等宏观影响的评价研究,提出了保护水环境、生态修复、防护与保护的战略对策措施。     

在广西全面开展悬移质泥沙简测的可行性和重要性

通过对百色等水文站泥沙资料分析 ,并结合广西河流及泥沙特性和社会对泥沙资料的精度要求 ,得出了在广西实行悬移质泥沙简测的可行性。为满足广西国民经济可持续发展需要 ,提出了在广西改革悬移质泥沙测验方式的必要性和紧迫性     

广东省伴生放射性矿资源利用过程辐射水平调查

为加强伴生放射性矿物资源开发利过程中放射性环境管理 ,防治放射性污染 ,对广东省几个大型伴生矿(包括稀土矿、钽铌矿和铅锌矿 )资源利用 (开采、冶炼、加工 )过程中天然放射性核素的污染现状进行了调查。调查结果表明 :稀土矿中独居石 ,天然放射性核素含量最高 ,2 3 8U、2 3 2 Th、2 2 6Ra的含量分别为 3.5 1× 1 0 4、1 .74× 1 0 5、4 .8×1 0 4Bq/kg,其冶炼废渣中核素的含量分别为 5 .1 0× 1 0 5、6 .38× 1 0 6、1 .5 2× 1 0 6Bq/kg。稀土选冶厂周围陆地环境 γ射线的空气吸收剂量率比一般地区的高。     

压型钢板组合楼板承载力的有限元分析

压型钢板组合楼板是 2 0世纪发展起来的一种新型结构形式。它具有显著的优势 ,如轻质、高强 ,施工快捷等 ,将在未来的建筑领域中大有作为。组合楼板的承载力主要取决于钢板 -混凝土界面处的抗剪强度。建立了一个二维有限元模型来研究单向组合板的性能。并将计算结果与试验数据进行对比 ,验证了模型的有效性     

The influence of the fabrication process on the buckling of thin-walled steel box sections

Steel box sections are usually fabricated from flat plates which are welded at the corners. The welding process can introduce residual stresses and geometric imperfections into the sections which can influence their strength. For some thin-walled sections, large periodic geometric imperfections have been observed in manufactured sections. Subsequent investigations have indicated that the imperfections are in fact buckling deformations i.e. the box section has buckled due to welding residual stresses prior to any application of external load. The welding procedure and the behaviour of the box sections under load has been modelled using a finite element analysis that accounts for both geometric and material non-linearities. Tests have been carried out on box sections with a range of width to thickness ratios for the plate elements. Modelling has been shown to give good correlation with the test results. The conditions for buckling to take place as a result of the welding process have been established. A design method has been proposed.     

聚苯乙烯生产工艺及其产品性能的改善

介绍了苯乙烯单体热引发本体聚合的特点及美国FINA石油化学公司聚苯乙烯生产工艺的特点，探讨了影响HIPS产品质量的多种因素，并对HIPS产品质量的改善提供提出建议和看法。     

大功率UPS的并联控制技术

提出了一种新的N 1三相大功率UPS的并联控制方案，并且在4台40KVA三相在线式UPS上进行了实验研究，实际运行结果证明采用此方法可以获得良好的静态与动态特性。     

Microscopic and Macroscopic Growth Rates of Fatigue Cracks in Steels and Alloys under the Influence of Crack Closure

On the basis of the experimental data, we show that the difference between the macroscopic and microscopic fatigue crack growth rates in the second section of the kinetic diagram of fatigue fracture is caused by the effect of crack closure within the limits of its existence. We establish the relationships between the macroscopic and microscopic fatigue crack growth rates and the structure of the material in the second section of the diagram for various values of the load ratio with regard for the effect of crack closure and propose a procedure of examination of the fracture processes in structural materials based on the analysis of microscopic and macroscopic fatigue crack growth rates.     

战术弹道导弹落点预报的一种方法

根据椭圆弹道理论，提出了一种可以用于反战术弹道导弹作战的预测弹道及预报落点的方法，给出了算例，并分析了产生误差的原因和对预测结果的影响程度。     

地下商场空调设计问题的探讨

本文分析了地下商场的特征 ,并相应提出了地下商场通风空调设计的有关数据、方法及注意事项