武陵山片区高质量景区空间分布格局及其影响因素

基于武陵山片区高质量景区POI数据,综合运用最邻近指数、核密度分析和空间叠加分析等方法,探析武陵山片区高质量景区空间分布格局及其影响因素.结果 显示:(1)武陵山片区高质量景区整体呈现集聚分布态势,在片区层面上,集中分布于湖北分片区和湖南分片区;在地市层面上,主要聚集于恩施州、怀化市、渝东南地区、湘西州、张家界市和铜仁市.(2)武陵山片区高质量景区分布密度的空间差异显著,湖北和湖南分片区表现出典型的"核心—边缘"结构,而贵州和重庆分片区核密度值自东向西梯度递减.(3)武陵山片区高质量景区空间分布格局受自然因素和人文因素影响显著,其中地形地貌、河流水系和空气质量既是重要的构景要素,也是高质量景区空间分布的重要内生动力;而区域经济、交通通达性、旅游发展能力和政府政策支持的外部调控作用明显.     

pH值对霞湾港沉积物重金属Zn、Cu释放的影响

以霞湾港(铜霞路段)的底泥沉积物为研究对象,采用重金属连续浸提法对重金属Zn、Cu在沉积物中的5种形态进行浸提,分析了其分布特征和在不同pH值与时间的条件下重金属的释放规律。研究结果表明,重金属Zn主要以铁锰氧化物结合态和碳酸盐结合态的形态存在,Cu主要以有机结合态和残渣态的形态存在,可交换离子态的重金属含量都很低。重金属Zn、Cu从沉积物中的释放,主要是在酸性条件下发生,在酸性区内释放量随pH的升高而迅速降低。释放能力和释放速率均为ZnCu,它们释放的过程基本相似,释放速率都比较小,向环境中的释放是个长期过程。     

高水分褐煤运煤系统的设计优化

针对火电厂燃用高水分褐煤时,堵煤故障频发的问题,以印尼某电厂为例,分析运煤系统出现堵煤故障的原因,提出设计优化方案。应用结果表明:采用齿辊破碎机替代一级筛碎设备,采用高幅筛+可逆锤破碎机替代二级筛碎设备,可逆锤破碎机的破碎板设电加热装置,同时修改落煤管的尺寸,可有效降低堵煤的故障率。     

三唑醇杀菌剂在雄性丽斑麻蜥体内的对映选择性降解、蓄积和肝毒性研究

三唑醇(triadimenol, TN)是一种广泛使用的手性三唑类杀菌剂,它含有2个手性中心,4个手性对映体,包括对映体A(A1(R,S)和A2(S,R))以及对映体B(B1(R,R)和B2(S,S))。为了研究三唑醇在爬行动物体内的对映选择性行为和潜在的肝毒性,将雄性丽斑麻蜥分别一次经口暴露和28 d长期暴露于三唑醇(100 mg·kg~(-1) body weight),一次经口暴露结果显示,三唑醇进入大脑和肾中的浓度低于肝、性腺、皮肤和尾,B2(S,S)和B1(R,R)对映体具有相似的代谢速率。代谢过程中A1(R,S)的浓度明显高于A2(S,R),并且在暴露后12 h出现二次上升,这可能是A2(S,R)在体内手性转换为A1(R,S)导致。丽斑麻蜥长期(28 d)暴露于三唑醇后,性腺和肾中无明显蓄积现象,皮和尾中浓度显著高于其他组织,各个组织中三唑醇趋向于保持外消旋状态。三唑醇暴露后肝中主要的代谢基因cyp1a1c、yp3a4c、yp2b1和cyp2d3的表达量都出现明显上升,组织病理学分析进一步显示,三唑醇暴露后的肝组织出现组织空泡、血窦阻塞的症状,说明三唑醇对肝组织具有一定的毒性作用。上述结果为手性农药对爬行动物的生态毒理学评价提供了重要依据。     

Effect analysis of carbon trading on Economy-Energy-Environment system and calculation of reasonable carbon price intervals

This paper constructs a 4-lier computable general equilibrium model which includes such modules as modeling carbon emission constraints and carbon trading(CT),and incorporates the cost of carbon emissions into constant elasticity of substitute production function.Under scenario settings under different carbon abatement targets,based on 2007 national social accounting matrix and related statistical data about energy consumption and carbon emission,effects on economic outputs,energy consumption,and carbon abatement are estimated and analyzed at both macro and sector level.By calculating selected novel indicators that compromise between macroeconomic opportunity cost and achievable carbon abatement,reasonable carbon price intervals are given for enhancing the robustness and liquidity of carbon market.Further,by decomposition and share-weighted methods,expected carbon abatement and energy price are measured and analyzed in details.Some results are meaningful for fundamental design of the future carbon market.Given constant energy utilization and carbon abatement technologies at the macro level,the higher the carbon price the more actual carbon abatement;the more gross domestic product loss,the less energy consumption.Accwding to the overall situation estimated for 2007 in China,the advice given is to introduce a carbon abatement target rate(R_c)of-10%,which is helpful to make carbon market stable against unexpected carbon price shocks between[6.9,35]/tC with less economic loss.According to Kaya decomposition,after introduction of carbon pricing,carbon abatement is mainly contributed by the effects of energy intensity(EI)and technical progress.Further,CT may help reduce energy consumption and induce transformation to a low-carbon energy structure.At the sector level,the introduction of CT could induce economic recession in all sectors,especially energy.However,the overall economic structure remains unchanged to some extent.CT will help reduce energy consumption in all sectors,especially energy.Overall utilization costs of the energy composite can be divided in two,market price and carbonrelated costs.Carbon-related costs mainly contribute to variation in the utilization cos of the energy composite;carbon pricing may help non-energy sectors achieve sufficient carbon abatement by pushing up energy utilization cost.However,despite achievable carbon abatement by the energy sector being relatively high,induced by carbon pricing,there is still significant potential for other incentive policies to stimulate further abatement,such as energy resources taxation and transportation fuel taxation,especially in the sectors of coal and transportation.Finally,some advice is proposed in regard to policy decisions and further research.     

Top-runner incentive scheme in China: a theoretical and empirical study for industrial pollution control

Environmental Science and Pollution Research - Pollution control policies have achieved remarkable results in China. However, industrial firms still lack enthusiasm for technological innovation to...     

发展西部特色农业 促进资源优势向经济优势的快速转变

本文在简要分析新形势下西部特色农业优势和劣势的基础上 ,提出了一些西部发展特色农业 ,促进资源优势向经济优势转变的发展对策和政策建议     

试论长江中游防洪减灾的工程对策

长江中游洪患自古乃中华民族的心腹大患,数百年来不得治愈的根本原因是没有做到对症下药。从洪患形成的地学环境分析和数百年抗洪经验总结来看,行洪不畅,泥沙淤积和长期以堵为主的抗洪方式是长江中游洪患得不倒根除的主要。疏－疏水和疏水是根治长江洪患的唯一出路,开辟分洪河道,疏沙淤垸降和蓄水分洪是长江中游共减灾的重要措施。     

用弱碱性离子交换树脂分离2-萘磺酸的研究

介绍了采用弱碱性离子交换树脂回收2－萘磺酸废水中的2－萘磺酸的试验研究。进行了pH、交换温度、共存阴离子等影响因素的条件试验及树脂再生试验,在较佳条件下,2－萘磺酸交换吸附率达98％以上,洗脱率接近100％。