近地表地球物理发展状况综述

随着人类社会进步和经济发展,近地表地球物理越来越多地受到人们的关注.文中首先介绍了世界各主要近地表地球物理学家组织,然后简要叙述了近地表地球物理学常用方法和近地表地球物理在环境、工程、考古等各领域的广泛应用以及仪器软、硬件的发展水平.最后结合学科发展要求以及实际应用需要,对今后的发展方向给出建议.     

34Mn6大断面圆管坯表面渣沟缺陷分析

本文结合理论并通过试验对比分析说明了 34Mn6大断面铸坯表面渣沟缺陷的成因 ,并制定了改善措施 ,为以后改进表面质量提供依据     

Corrosion of a stainless steel handrail

AISI 304 and 304L stainless steels are “workhores” grades of austenitic stainless steel frequently used in architectural applications, as well as in cookware, appliances, and numerous other applications where resistance to corrosion is required. This paper examines a corrosion failure (the appearance of rustlike stains on the surface) of a 304 stainless steel handrail that appears to have occurred as a result of contamination during the fabrication process.     

Waves Past Porous Structures in a Two-layer Fluid

Havelock’s type of expansion theorems, for an integrable function having a single discontinuity point in the domain where it is defined, are utilized to derive analytical solutions for the radiation or scattering of oblique water waves by a fully extended porous barrier in both the cases of finite and infinite depths of water in two-layer fluid with constant densities. Also, complete analytical solutions are obtained for the boundary-value problems dealing with the generation or scattering of axi-symmetric water waves by a system of permeable and impermeable co-axial cylinders. Various results concerning the generation and reflection of the axisymmetric surface or interfacial waves are derived in terms of Bessel functions. The resonance conditions within the trapped region are obtained in various cases. Further, expansions for multipole-line-source oblique-wave potentials are derived for both the cases of finite and infinite depth depending on the existence of the source point in a two-layered fluid.     

表面化学改性活性炭在水处理中的应用

介绍表面化学改性活性炭研究进展,针对其特点和改性方法作了系统描述.在此基础上,对其去除水中有机物、重金属离子、亚硝酸盐等污染物质做了简要说明.     

纳米CeO2的紫外吸收和表面改性研究

紫外吸收光谱分析氨水沉淀法制备的粒度在10nm的纳米二氧化铈表明在200～480nm的范围具有较好的紫外吸收能力。用无水乙醇为溶剂,硬脂酸为改性剂,初步探讨了纳米CeO2进行表面改性机理。活化度和吸油值分析表明,当硬脂酸用量在2．5％时,已经有较好改性效果,为纳米CeO2在聚合物中的应用提供一定的参考价值。     

DInSAR监测地表三维形变的方法

本文介绍了几种利用DInSAR技术监测地表三维形变的方法,并深入分析了它们各自的优缺点,对它们的使用条件和使用中的应注意的事项进行了讨论。对于DInSAR监测地表三维形变方法的选择,应取决于数据条件,地质情况以及精度等几个因素。文章的最后展望了DInSAR监测地表三维形变方法的发展趋势。     

Study on calculation method of surface subsidence about the dewatering concretion of clay influenced by mining

Under the condition of thick alluvia, there is biggish declination in predicting the coal mining subsidence by commonly strip design method compared with the practical observation, the sinkage is much smaller. Based on the method of the probability integral about coal mining subsidence calculation, discussed the surface subsidence calculation and deduced the formulas caused by the clay with dewatering. The results show that the clay dewatering has great impact on surface subsidence. Therefore, the clay dewatering on surface subsidence should not be overlooked.     

地表水监测存在的问题及改进方法研究

随着工业生产和科学技术的迅猛发展,环境污染问题越发严重,严重影响了人们的生活质量.地表水是常见的一种水体形式,本研究探讨地表水监测存在的问题及改进方法,为改善环境污染提供参考.