基于生态足迹分析的义乌市生态承载力评价

传统生态足迹计算方法过于依赖统计年鉴,尤其是两个十分重要的数据:土地利用因子、产量因子均来自普查统计数据,由此产生的误差对生态足迹的计算结果影响较大。随着遥感技术发展的日益成熟,当前基于遥感技术实现土地利用和产量因子的准确监测已成为可能。因此,本研究通过遥感监测获取土地利用和产量因子,然后对义乌市2000年和2007年的生态足迹分别计算,并进行了动态变化分析。结果显示,义乌市生态承载力在急剧下降,并基于以上结果,提出几点关于减缓义乌市生态足迹增长速度、确保城市的可持续发展的建议。     

基于虚拟样机的三缸柱塞泵动力学仿真分析

建立三缸柱塞泵三维模型,并应用ADAMS进行动力学仿真分析,得出了三缸柱塞泵各柱塞的位移、速度、加速度曲线,以及各部件的受力、载荷、曲轴的扭矩曲线。根据上述曲线可以对三缸柱塞泵的运动平稳性作出评价,为后续的有限元分析、产品优化设计提供参考。     

基于虚拟样机的三缸柱塞泵动力学仿真分析

建立三缸柱塞泵三维模型,并应用ADAMS进行动力学仿真分析,得出了三缸柱塞泵各柱塞的位移、速度、加速度曲线,以及各部件的受力、载荷、曲轴的扭矩曲线。根据上述曲线可以对三缸柱塞泵的运动平稳性作出评价,为后续的有限元分析、产品优化设计提供参考。     

Separation of Eu（III） with supported dispersion liquid membrane system containing D2EHPA as carrier and HNO3 solution as stripping solution

The Eu(III) separation in supported dispersion liquid membrane (SDLM),with polyvinylidene fluoride membrane (PVDF) as the support and dispersion solution containing HNO3 solution as the stripping solution and Di(2-ethylhexyl) phosphoric acid (D2EHPA) dis-solved in kerosene as the membrane solution,was studied.The effects of pH value,initial concentration of Eu(III) and different ionic strengths in the feed phase,volume ratio of membrane solution and stripping solution,concentration of HNO3 solution,concentration of carrier,different stripping agents in the dispersion phase on the separation of Eu(III) were also investigated,respectively.As a result,the optimum separation conditions of Eu(III) were obtained as the concentration of HNO3 solution was 4.00 mol/L,concentration of D2EHPA was 0.160 mol/L,and volume ratio of membrane solution to stripping solution was 30:30 in the dispersion phase,and pH value was 5.00 in the feed phase.Ionic strength had no obvious effect on the separation of Eu(III).Under the optimum conditions studied,when initial concentration of Eu(III) was 1.00×10–4 mol/L,the separation rate of Eu(III) was up to 94.2% during the separation period of 35 min.The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry.The results were in good agreement with the literature data.     

Study on transport of Dy（III） by dispersion supported liquid membrane

The transport of Dy(III) through a dispersion supported liquid membrane (DSLM) consisting of polyvinylidene fluoride membrane (PVDF) as the liquid membrane support and dispersion solution including HCl solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (PC-88A) dissolved in kerosene as the membrane solution, was studied. The effects of pH value, initial concentration of Dy(III) and different ionic strength in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HCl solution, concentration of carrier, different stripping agents in the dispersion phase on transport of Dy(III) were also investigated, respectively. As a result, when the concentration of HCl solution was 4.0 mol/L, concentration of PC-88A was 0.10 mol/L, and volume ratio of membrane solution and stripping solution was 40:20 in the dispersion phase, and pH value was 5.0 in the feed phase, the transport effect of Dy(III) was the best. Ionic strength had no obvious effect on transport of Dy(III). Under the optimum condition studied, when initial concentration of Dy(III) was 0.8 × 10^?4 mol/L, the transport rate of Dy(III) was up to 96.2% during the transport time of 95 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The diffusion coefficient of Dy(III) in the membrane and the thickness of diffusion layer between feed phase and membrane phase were obtained and the values were 1.99 × 10^?7 m²/s and 15.97 μm, respectively. The results were in good agreement with experimental results.     

可渗透反应墙原位修复污染地下水研究进展

可渗透反应墙是一种替代抽提技术的创新型地下水原位修复技术。在实际工程中大量不同种类的填料被应用在墙体上,通过吸附、沉淀、氧化还原和生物降解等作用,可处理包括重金属、苯系物、卤代烃、芳香烃、农药以及无机阴离子等污染物。综述了可渗透反应墙的结构、去除污染物机理、优缺点以及活性填料的应用,详细介绍了可渗透反应墙技术的最新研究进展,指出该技术虽已得到广泛认可,但其长期性能尚待实践证明。     

滴灌工程施工方法及运行管理 模式分析(II)

滴灌工程中科学合理的施工和运行管理是保证工程质量和系统正常运行的关键，结合施工和 运行管理经验，在对滴灌工程主要环节的施工方法和运行管理模式进行了分析的基础上，总结了滴灌 工程施工及运行管理中存在的问题，分析这些问题存在的原因，提出相应的处理对策和方法，为该技 术的进一步推广应用提供参考。     

高斯反算三种实用算法的比较研究

设计实现了三种简单的高斯反算算法,即一种直接算法和两种迭代算法。试验表明,三种算法结果相同,均达到了0.00001秒的精度,可以代替此等精度比较复杂的反算算法,具有实用价值。     

Visual Basic环境下图像锐化处理的探讨

在Visual Basic中提供了较强的图形和图像的处理功能。Visual Basic对图像进行锐化处理的原理主要是从图像上获取某一像素的颜色,再对颜色进行模板和卷积操作从而达到锐化的效果。     

基于Matlab小波变换的遥感影像两种压缩方法对比研究

使用Matlab小波函数和小波工具箱分别对遥感影像进行了压缩,通过对压缩结果进行对比研究,证明小波工具箱具有更大的压缩比和更好的图像质量。