射水法结合高压喷射技术在堤基防渗处理中的应用

通过工程实例介绍了在特殊条件下射水法和高压喷射两种工艺相结合进行堤基防渗处理的施工工艺及实施的效果。     

山区生态县区域协调发展的机制构建--以粤北始兴县为例

区域协调机制在不同类型地域和一种类型地域的不同的发展阶段是不同的。始兴县作为一个典型的山区生态县,工业进入加速发展时期,在此经济发展阶段的区域协调问题主要表现在:与外部区域经济、社会发展差距拉大,工业化与流域生态环境保护的矛盾已开始凸现,县政府协调区域发展的财政能力较低,区域协调机制不健全等。由此对始兴县的区域协调机制进行建构:建立健全多层次的区域协调机构;加大纵向和横向政府财政转移支付的力度;加强与相邻相关地区的协调;实施区域空间管治协调,保护城乡生态环境;科学合理选择产业,大力发展循环经济;全县推行绿色GDP考核等。     

Speciation of sulfate components in size-fractionated aerosol particles using sulfur K-edge X-ray absorption near-edge structure （XANES）

Sulfates are a main constituent of aerosols, which sulfate aerosols, it is necessary to determine what can cause various environmental problems sulfate ions are contained in these aerosols In the evaluation of the influence of In this study, sulfur K-edge XANES was used to determine sulfate species present in size-fractionated aerosol particles based on the post-edge structure after the main absorption peak in the XANES region. Aerosol samples were collected as part of the Japan-China joint project, ＂Asian Dust Experiment on Climate Impact＂ using a low-volume Andersen-type air sampler. XANES was measured at Beamline BL-9A at Photon Factory, Japan. A comparison of the XANES spectra of reference sulfate materials and aerosol samples collected in Tsukuba in Japan clearly showed that （NH4）2SO4 was the main sulfur species in particles with a smaller diameter and gypsum was the main sulfur species in particles with a larger diameter. A simulation of the XANES spectra by reference materials allows us to obtain the quantitative mixing ratios of the different sulfate species present in the aerosol samples. The presence of minor sulfur species other than （NH4）2SO4 and gypsum at the surface of mineral aerosols is suggested in our simulations and by a surface-sensitive conversion electron/He-ion yield XANES. In the absence of a contribution from a large dust event, the mole concentration of gypsum in the mineral aerosol fraction determined by XANES is similar to that of Ca which is determined independently using ion chromatography. This shows that the Ca and sulfate in the mineral aerosols are present only as gypsum. Considering that calcite is the main Ca mineral in the original material arising from an arid and semi-arid area in China, it is strongly suggested that gypsum is formed in aerosol during its long-range transportation by a reaction between calcite and sulfate ions.     

地理教学中探究性问题情境的创设

新一轮的课程改革对地理学习过程提出了新的要求。顺应课改要求,本文就地理教学中如何创设探究性问题情境作了初步的探讨,认为创设探究性问题情境应符合“新颖性、开放性、启发性”等要求,根据不同的教材内容、不同的学生情况,应有不同的教学方式,以求取得最佳成效。     

我国煤炭资源开发利用中某些问题的探讨

针对我国煤炭资源开发利用中存在的诸如煤炭资源的低效率应用、无序开采、生态环境恶化等问题，指出了我国煤炭资源管理法规中存在的问题，提出了加强煤炭资源开发管理、构建煤炭循环经济体系、加大安全投入、加强煤炭矿区环境的治理和保护、健全有偿使用资源法规制度等对策。     

Application of membrane technology for water treatment： Ultrasound-associated cleaning of fouled microfiltration membranes

The use of membranes is a widely employed, versatile, and effective separation process. One of the limiting aspects in applying microfiltration （MF） for wastewater treatment is that of problems with membrane fouling and consequent flux reduction. Membrane fouling occurs by the irreversible deposition of retained particles, colloids, macromolecules, salts, etc. at the membrane surface and/or inside the membrane. The predominant fouling mechanisms observed with MF membranes are classified as three categories： the build-up of a cake layer on the membrane surface, blocking of membrane pores, and adsorption of fouling material on the membrane surface or in the pore walls. Although many techniques have been developed to overcome fouling, studies on membrane cleaning still seem to be insufficient for practical membrane filtration systems. Current membrane cleaning technologies include hydraulic, chemical, and mechanical methods. Ultrasound （US） has been widely used as a method of cleaning materials because of the cavitation phenomenon. In this study, US cleaning technique was applied to removing the fouling of polyvinglidenefluoride （PVDF） MF membrane, which was used to treat yeast cell and isolated soybean protein （ISP） solution, respectively. The US employed 40 kHz frequency and the output power of 1.43-2.85 W/cm^2. The evolution of the cleaning effect is followed by the measurements of the flux recovery rate （FRstat） and the cleaning time cycle. Results showed that the membrane property, which was fouled by yeast cell solution, could be recovered by water cleaning with US irradiation. And the cleaning time with the same FRstat decreased with the increase of US intensity.     

基于LSB的遥感图像安全传输模型

互联网在方便人们交流、共享信息的同时,也带来了极大的安全问题.信息隐藏是解决信息安全的一种有效手段,研究采用LSB法实现重要目标遥感图像信息的隐藏,实验证明该方法可以有效地解决网上图像传输出现的安全问题.     

新型导线在水电工程测量中的应用

结合山岭重丘地区的一水电工程,根据其特殊的地形条件,采用新型的导线布网形式,避免树木的大量砍伐,确保通视良好;再利用全站仪观测,按导线的严密坐标平差方法,运用MATLAB6.1软件对测量数据进行处理,计算出各控制点的坐标,得到满意的结果.     

基于数据手套和跟踪器的虚拟手臂建模

文中利用数据手套和跟踪器获取手臂各关节运动数据,根据关节运动限制对所获取数据进行处理,建立了符合人体运动规律的虚拟手臂数学模型,实现了虚拟环境中与试验者的手臂同步运动、效果逼真的虚拟手臂模型.