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采煤塌陷地规划整理项目包括塌陷地资源评价,开发可行性论证,开发目标和方向,土地利用结构和布局,配套的生态工厂设施等.通过阜新矿区采煤塌陷地灌溉工程、土地平整工程、地块划分以及道路工程、林地工程、电力工程的设计,对大面积的固定土壤,从防止土地荒漠化,提高土壤肥力,改良土壤理化性态,改善区域性的生态环境角度,试图改变煤矿沉陷区农业单一种植粮食的简单结构,对干旱沉陷区推广草畜结合生态模式,使阜新煤矿沉陷区形成以草兴牧,以牧兴农的良性循环. 相似文献
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研究了Ce4+在以2-(二乙基己基)磷酸(P204)为流动载体,煤油和P204的混合溶液作为膜溶液,膜溶液和解析剂H2SO4溶液组成更新相的反萃更新中空纤维液膜(SRHFLM)中的提取行为;考察了料液酸度、更新相H2SO4浓度、膜溶液与H2SO4溶液体积比、不同载体浓度对Ce4+提取的影响,得出了以下Ce4+最优提取条件:更新相H2SO4溶液浓度2.50mol/L,膜溶液与H2SO4溶液体积比2:1,载体浓度控制在0.200mol/L,料液相酸度为0.05mol/L。在最优分离条件下,当Ce4+的初始浓度为1.00?10-4mol/L时,Ce4+在45min时提取率达到92.2%。最后提出了Ce4+在SRHFLM中的学渗透系数动力学模型。 相似文献
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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,concentr... 相似文献
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Along with the increasing demand for coal and the great importance attached to mine safety, gaining the information of mine
surface distortion timely has already become an urgent need to guarantee the safety of mine production. D-InSAR technology
is a new measure which can provide the information of surface distortion in mining areas at centimeter level through the processing
of SAR image gained from radar satellite. In addition, this technology has the advantage of monitoring large areas with no
weather limit. Introduced the basic principle and data processing steps of D-InSAR systematically and acquired the differential
interferometry based on case study data. The advantages of D-InSAR and it’s usability in monitoring mining subsidence in coal
mining areas were proved. 相似文献
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连锁有三个大的分类,一个叫做直营连锁,典型的例子就是像沃尔玛、家乐福这样的,一种叫特许经营,也叫特许假加盟,也叫加盟连锁,这种方式代表的企业就是麦当劳、肯德基,还有一种就是自愿连锁,就是一些企业大家自愿的组合在一起的连锁店。 相似文献