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621.
2008年初冰雪灾害对生命线工程的几点启示   总被引:2,自引:0,他引:2  
2008冰雪灾害对我国生命线工程造成了巨大损失。本文分析了雪灾对生命线工程造成损失的程度、特点、致灾因子、及其生命线工程之间的关联性,对我国生命线工程建设提出了几点建议,呼吁国家要重视防灾减灾工程的人才培养和科技投入。  相似文献   
622.
We studied the energy and economic flow of six types of homegardens in Sanjia village, SW China. Our study showed that the energy input of six types of homegardens averaged 99.11-175.65 x 1010J/ha, the energy output was 102.30-159.83 x 1010J/ha and the ratio of input/output ranged between 1:0.880-1:1.416. The ratios of input to output of home-gardens that prioritized cultivation of crops were higher than for homegardens that prioritized animal husbandry or other economic activities. The economic ratio of input/ output of six types of homegardens varied between 1:0.997-1:1.376 and the economic output ranged between 2480.0-10131.5 RMB/yr. We concluded that the homegarden systems of Sanjia village are high in the input and output of energy and cash flow, and can provide a basis for designing models of farm economy in rural subtropical areas.  相似文献   
623.
含油污泥是石油开采及加工过程中产生的含油量高、脱水难、水溶性小的固体废物。文章主要介绍了国内物化技术处理含油污泥研究的现状及进展,包括洗脱、萃取、调质分离、热洗、调剖等。对这些方法进行了评价和比较,并对今后的研究方向提出建议,需要在微波、超声波和调剖剂上作进一步研究。  相似文献   
624.
水体溢油事故会造成严重的环境污染,快速、准确、完整的水质石油类检测技术成为科学处置突发性水体溢油事故的关键。文章从石油类检测前处理技术和定量检测技术两个方面,系统地论述了国内外水质石油类检测技术研究进展,并进行分析与展望,为溢油事故中水质石油类检测技术的进一步探索研究提供参考。  相似文献   
625.
Environmental Science and Pollution Research - As a commonly used amendment to soil contaminated by heavy metals, biochar has attracted great attention and has been applied for decades due to the...  相似文献   
626.
Waste incineration bottom ash and treated flue gas cleaning products mixed with 2.5% of cement (50 kg/m3) were tested in the laboratory in terms of compressive strength and tank leaching tests over a 64-day period. Although the material displayed lower mechanical strength than a reference concrete, the strength still was sufficient for use as a base layer for roads. The metal content in the incineration-residue-based specimens was up to 100 times higher than in the reference concrete, suggesting that the mixed waste incineration residue should be used only for dedicated purposes. The leaching of Cl and Na was increased by a factor of 20-100 from the incineration-residue-based specimens as compared to the reference, while the leaching of K, Ca and SO4 was increased by a factor of 2-10. The leaching of heavy metals was also higher from the incineration-residue-based specimens than from the reference with respect to Cu (50 times), Cd, Pb and Zn (5 times), but not with respect to Cr and Ni. The leaching curves did only allow for a closer evaluation of the leaching process in a few cases. The physical retention of the constituents seemed to be the same in the reference as in the incineration-residue-based specimens. Heavy metal leaching was limited by enhanced chemical retention in the incineration-residue-specimens as compared to the reference. Since no quality criteria in terms of leaching from a monolithic material are currently available, the leaching issue must be evaluated case by case.  相似文献   
627.
Poultry operations are associated with emissions of aerial ammonia (NH3), volatile organic compounds (VOCs), and odor, and the magnitude of emissions is influenced by manure management practices. As a manure treatment additive, zeolites have been shown to have the potential to control NH3. Because of their properties it is also expected that zeolites could effectively adsorb VOCs and odor. The effectiveness of zeolite in controlling odor and VOCs was qualitatively evaluated in this controlled laboratory study involving simulated poultry manure storage. In the first two trials, zeolite was topically applied on nearly fresh laying hen manure at the rates of 0, 2.5, 5, and 10% (by weight). In the third trial, zeolite was topically applied at 5% with each addition of fresh manure into the storage vessel. Headspace samples from the emission vessels were collected with solid phase microextraction (SPME) and analyzed on a multidimensional-gas chromatograph-mass spectrometry-olfactometry (MDGC-MS-O) system for identification and prioritization of poultry manure odorants. Acetic acid, butanoic acid, isovaleric acid, indole, and skatole were consistently controlled in the headspace, with the reduction rate being proportional to the zeolite application rate. Dimethyl trisulfide and phenol were consistently generated, and with a few exceptions, the rate of generation was proportional to the application rate. Average reduction of the odor caused by all odorants evaluated with SPME-GC-O was 67% (+/-12%) and 51% (+/-26%) for the two topical applications, respectively, while no significant reduction of VOCs and odor was detected for the layered application.  相似文献   
628.
为了研究苯并(b)荧蒽这一典型的多环芳烃化合物对水生生物的毒性效应,测定了不同浓度(2.0、10.0和50.0 μg· L-1)苯并(b)荧蒽胁迫15 d和清水释放10 d后翡翠贻贝(Perna viridis)内脏团组织中抗氧化酶(CAT、SOD和GPx)活性和MDA含量的变化.结果表明,2.0 μg· L-1浓度组...  相似文献   
629.
论加强环境保护基础设施建设   总被引:1,自引:0,他引:1  
加强环境保护基础设施建设是扩大内需,拉动经济发展的重要措施,可带来可观的经济,社会和环境效益,并可改善投资结构,产业结构和生产力布局,同时也是综合整治环境污染和破坏,保护和城乡环境质量的基本扩大内需加强环境保护基础设施建设,环境保护部门应积极参与综合决策,选基础设计项目,加大投资力度,加强投资监客,并通过推行污染集中控制,区域控制和综合防治来引导和加强环境保护基础设施建设。  相似文献   
630.
此文介绍了摩托车齿轮类零件的工艺规程自动生成系统。该系统直接从CAD系统中获取零件的有关信息,根据此文所建立的特征体素描述方法,自动生成零件的特征编码,采用零件自动识别的方法实现CAD/CAPP的信息集成,利用工艺知识库,通过工艺决策模型的分级推理,实现齿轮类零件的工艺过程设计的自动化。  相似文献   
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