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181.
SWOT分析模型在巴彦淖尔市战略环境评价中应用研究   总被引:1,自引:0,他引:1  
SWOT分析模型是战略规划研究的一种分析技术,近年来在区域规划研究中得到广泛利用。本文在进行巴彦淖尔市发展规划环评中,从环境保护角度出发,采用SWOT分析方法对区域经济发展的优势、劣势、机遇和压力进行了分析,提出巴市经济发展策略应突出增长型战略,同时兼顾其他三类发展战略,构建经济快速发展、优势资源保护性开发、环境压力显著降低的生态型工业集群的建议,有助于促使区域经济实现友好又快发展,且对今后偏重政策层面的战略环评编制具有一定的参考价值。  相似文献   
182.
逐级分离法提取河流表层沉积物中的粘土矿物   总被引:2,自引:0,他引:2  
采用选择性化学萃取剂对河流表层沉积物中的有机质、铁/锰氧化物进行逐级分离,并依据斯托克斯(Stokes)法则提取其中的粘土矿物,以达到逐级分离的效果.利用TOC测定法和火焰原子吸收法(FAAS)定最分析并验证沉积物中碳酸盐、有机质和铁、锰氧化物的去除效果;利用X-射线衍射(XRD)和扫描电镜(SEM)考察粘土矿物的主要成分和提取效果.结果表明,有机质的去除率可达到90%以上,铁、锰氧化物的去除率分别达到98.90%和77.92%,占可萃取态铁、锰的绝大部分;沉积物中粘土矿物的主要成分为伊利石、伊利石/蒙脱石混层和高岭石,非粘土矿物的主要成分是石英和正长石,沉积物提取粘土矿物前后的XRD以及ESEM谱图的变化进一步验证了粘土矿物的提取效果.  相似文献   
183.
To recycle the sludge resource from sewage treatment plants and solve the problem of odor pollution, the sludge was converted into an adsorbent by carbonized pyrolysis and the process was optimized by orthogonal experiments. The capability for odor removal as well as the structure of the adsorbent was studied with H2S as a target pollutant. The results indicate that the main factor affecting the deodorization performance of the adsorbent is the activating time. The sludge adsorbent sample SAC1 prepared under optimum conditions exhibits the best deodorization performance with a H2S breakthrough time of 58 min and an iodine value nearly that of the coal activated carbon. The breakthrough time of H2S is much longer than that on the coal activated carbon. On the other hand, characterization results from X-ray diffractometer (XRD), X-ray photoelectron spectrometer (XPS) and scanning electron microscope (SEM) techniques show that SAC1 is composed of mainly graphite carbon with lower oxygen content on the surface. The bulk of SAC1 exhibits a honeycomb structure with well developed porosity and a high specific surface area of 120.47 m2·g-1, with the average pore diameter being about 5 nm. Such a structure is in favor of H2S adsorption. Moreover, SAC1 is detected to contain various metal elements such as Zn, Fe, Mg, etc., leading to a superior deodorization property to that of coal activated carbon.  相似文献   
184.
In this study, DOW CORNING 1-2577 Conformal Coating was proposed for the cathode diffusion layer of the microbial fuel cell (MFC). In MFCs, stainless steel mesh cathodes using DOW CORNING 1-2577 Conformal Coating/carbon as the diffusion layer and two poly (dimethylsiloxane) (PDMS)/carbon diffusion layers and carbon cloth cathode with four poly (tetrafluoroethylene) (PTFE) diffusion layers were constructed for comparison. Under the same operational condition, the MFCs with the DOW CORNING 1-2577 Conformal Coating/carbon diffusion layer produced the maximum power density of 1585±52 mW·m-2, compared with those using poly (tetrafluoroethylene) (PTFE) diffusion layers (1421±45 mW·m-2) and poly (dimethylsiloxane) (PDMS)/carbon diffusion layers (1353±49 mW·m-2). The DOW CORNING 1-2577 Conformal Coating could be an alternative for the diffusion layer construction in the MFC due to its remarkable performance and much simple construction procedure.  相似文献   
185.
黑龙江省霜冻的气候变化特征和预报指标   总被引:1,自引:0,他引:1  
利用1970-2008年地面最低气温和历史天气图资料,对黑龙江省初、终霜冻的天气气候特征进行了分析,并探讨了出现霜冻的环流形势特点,总结出黑龙江省出现霜冻的三种天气学模型:①超极地路径型;②西方路径型;③西北路径型。给出了霜冻的时空分布特征以及对预报有用的一些预报指标,对霜冻预报业务有参考作用。  相似文献   
186.
为考察调节pH值对剩余污泥好氧消化效果的影响,采用2个反应器,在不调节pH值与加入NaHC03调节pH≈7两种条件下进行好氧消化对比试验.监测消化过程中污泥TSS、TVSS、SOUR、沉降性及比阻的变化情况,结果表明:在两种条件下污泥均能达到稳定,消化30 d TVSS去除率分别为47.1%和49.2%.消化过程中调节pH≈7,TSS、TVSS去除率略有提高,上清液的浊度和COD降低,并且污泥的沉降、脱水性能改善,因而更有利于后续的处理.  相似文献   
187.
A high-swelling superabsorbent was synthesized with biodegradable N-maleyl chitosan as cross-linker, acrylic acid (AA) and acrylamide (AM) as the monomers, ammonium peroxodisulfate–sodium bisulfite (NaHSO3) as redox initiation system, by means of aqueous solution polymerization. The best reaction condition was based on the orthogonal experiment design. The optimal conditions on distilled water absorbency and on 0.9 wt% NaCl solution absorbency were monomer concentration 20 wt%, mole ratio of AA to (AA + AM) 60%, the neutralization degree of AA 40%, cross-linker concentration 2% and monomer concentration 25 wt%, mole ratio of AA to (AA + AM) 60%, neutralization degree of AA 50% and cross-linker concentration 1%, respectively. Factors influencing the water absorbency of superabsorbent also were investigated, by single factor experiment method. The absorbency of superabsorbents in distilled water and 0.9 wt% NaCl solution increased and then decreased with the increasing of monomer concentration, mole ratio of AA to (AA + AM) and degree of neutralization of AA. With the increasing of cross-linker concentration, the absorbency in distilled water increased and then decreased, but it decreased all the time in 0.9 wt% NaCl solution. In enzymatic degradation tests, the weight loss of superabsorbent was related to the content of cross-linker.  相似文献   
188.
根据消弧线圈容量及所在系统电容电流现状、系统中电气设备绝缘类型,依据相关技术标准,对宁夏电网消弧线圈配置现状进行了分析,提出了消弧线圈应根据配网结构采取分区配置,固体绝缘为主的系统不宜采用消弧线圈的建议。分析结果表明:采取消弧线圈的分区配置方式不仅能够避免消弧线圈配置不合理造成的浪费,而且能够有效消除弧光单相接地对配电网安全运行的威胁。  相似文献   
189.
Liu Y  Yu N  Li Z  Wei Y  Ma L  Zhao J 《Chemosphere》2012,89(7):893-899
Concentrations of polycyclic aromatic hydrocarbons (PAHs) were detected in sediment cores and surface sediment samples from the Liangtan River of Chongqing, Southwest China. The total concentration of 16 PAHs ranged from 69 to 6251 ng g−1. The spatial distribution of the PAHs reflects the intensity and scope of human activity in the catchment. A historical record of PAH contamination was reconstructed using a sediment core from a background segment of the river. The characteristic changes of concentrations, fluxes and patterns of 16 PAHs over the past ∼90 years were captured in detail. An obvious peak of PAH concentration and flux was found in the 1940s, i.e., during war time, and then a sharp increase was observed from the early 1980s to the present. The maximum concentration and flux reached 1260 ng g−1 and 470 ng cm−2 year−1, respectively. The sharp increase was attributed to the contribution of pyrogenic sources of PAHs. The population, length of highways and energy consumption of Chongqing, as indexes of socioeconomic development, were positively correlated with PAH input in the sediment core from the 1950s to the present. The results clearly show that the local socioeconomic development in the last decades remarkably aggravated the environmental load of sedimentary PAHs.  相似文献   
190.
含油污泥特性分析与研究   总被引:2,自引:1,他引:1  
含油污泥的性质决定其处理工艺及无害化、资源化利用的方式。通过对某油田原油处理系统和污水处理系统产生的含油污泥的理化性质及成分进行检测分析,探讨含油污泥的含油率、含水率、挥发固体、灰分、硫含量、pH值的测定方法,并从以上几个方面对含油污泥的理化性质进行了分析,为下一步含油污泥减量化、资源化、无害化处理提供技术选择的依据。  相似文献   
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