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471.
蔡世贵 《安全.健康和环境》2009,9(9):49-49,53
企业要搞好安全生产工作,必须坚持以人为本。因为人是生产过程中最活跃的要素,是安全生产的实践者,安全文化的核心。在企业安全文化建设中,如何坚持以人为本呢? 相似文献
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473.
针对EDTA滴定法测定水中总硬度(简称标准法)时,缓冲溶液配制繁琐,耗时较长的情况,提出了对缓冲溶液配制的改进方法(简称改进法)。改进法很好地克服了标准法的不足。通过地表水、地下水以及总硬度标准样品的比对测定,两者的测定结果无显著差异。 相似文献
474.
以钢铁酸洗废水为研究对像,研究一种基于微波催化纳米气泡氧化的工艺技术,对废水进行深度净化回用,其特征是:使废水中水、铁、酸有效分离,各自回用,全系统近乎零排放。 相似文献
475.
Veterinary antibiotics can enter the environment due to the common practice of land application of manure from treated animals. The environmental fate of tetracyclines in swine manure after composting and field application remains largely unknown. This study analyzed the concentrations of tetracyclines in manure, manure-based compost and compost amended soil in selected swine farms from Beijing, Jiaxing and Putian, China to determine the dilution effects of antibiotics when released into the soil environment. The results demonstrate that residues of antibiotics were detected in all samples and chlortetracycline as well as its degradation products should be regarded critically concerning their potential ecotoxicity. Application of manure-based compost to soil could reduce the possible risk posed by antibiotic contamination, but the trigger value of 100 μupg/kg was still exceeded in soil samples (776.1 μupg/kg dw) from Putian City after application of compost. Field studies such as the present one can help to improve the routine administration of antibiotic-containing composted manure. 相似文献
476.
Cyanobacteria, specifically Microcystis, usually form massive blooms in eutrophic freshwater lakes. Cyanobacterial samples were collected from eight sites of both Lake Taihu and Lake Chaohu in late summer to determine the diversity and distribution pattern of cyanobacteria and Microcystis in large, shallow, entropic lakes with significant spatial heterogeneity and long-term Microcystis bloom. Molecular methods based on denaturing gradient gel electrophoresis and clone library analysis were used. A similar heterogeneous distribution pattern of cyanobacteria in both lakes was observed. Most parts of these two lakes with high trophic level were dominated by Microcystis. However, in the regions with low trophic levels as well as low concentrations of chlorophyll a, Synechococcus occupied a considerable percentage. Different morphospecies and genotypes dominated the bloom-forming Microcystis populations in these two lakes. Microcystis viridis and Microcystis novacekii were dominant in Lake Chaohu, whereas Microcystis flos-aquae was dominant in Lake Taihu. Only 2 of the13 Microcystis operational taxonomic units were shared between these two lakes. Analysis of molecular variance based on 16S to 23S internal transcribed spacer sequences indicated the significant genetic differentiation of Microcystis between these two lakes (Fst = 0.19, p < 0.001). However, only 19.46% of the genetic variability was explained by the population variation between lakes, whereas most (80.54%) of the genetic variability occurred within the lakes. Phylogenetic analysis revealed no phylogeographic structure of Microcystis population in these two lakes, as illustrated by their cosmopolitan nature. Our results revealed that spatial heterogeneity within lakes has more impact on the cyanobacterial diversity than geographical isolation in a local scale. 相似文献
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478.
蔡小平 《防灾技术高等专科学校学报》2012,(4):102-106
救荒是明代经济发展、社会稳定的重要措施。为了保证荒政的顺利而有效地进行,明太祖从灾害防治到灾害赈济,从赈灾官员的选用到对吏治腐败的整治,都制定了较为详细的法律条文。从这些法律条文中可以概括出明太祖的荒政立法包含以下两个方面:一、防灾与减灾中的立法;二、救灾中的立法。朱元璋通过荒政立法,一方面惩治了救灾中的腐败,提高了救灾的效率;另一方面也使灾民在自然灾害面前得到国家的救济,使社会生产力的破坏得以减轻,为明王朝的经济恢复和发展奠定了基础。 相似文献
479.
通过分析炼油厂硫的分布和流向,介绍催化裂化装置SO2生成及排放情况,明确了催化裂化装置SO2排放源及其分类。依据SO2排放的环保控制要求,提出催化裂化装置SO2排放控制方法:催化裂化原料加氢预处理、使用硫转移催化剂和烟气脱硫。 相似文献
480.
利用"十五"系统对所选取的地震事件进行了重新定位,将震中位置与"九五"系统输出的地震目录进行对比分析,得到两套系统在定位结果方面的一致性。同时,对HYP02000和HYPOSAT两种定位方法的适用性进行了比较。 相似文献