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281.
为科学防治泥石流灾害对桥梁工程的危害,开展泥石流灾害影响下桥梁工程易损性评价尤为重要.提出一种基于变权-靶心贴近度模型的泥石流灾害影响下桥梁工程易损性评价方法.该方法首先从桥梁抗灾能力、泥石流破坏能力和桥梁恢复能力三个方面选取桥梁工程易损性评价指标,建立了泥石流灾害影响下桥梁工程易损性评价指标体系与易损性分级标准;然后...  相似文献   
282.
Environmental Science and Pollution Research - Coal gangue hills are prone to spontaneous combustion, thereby polluting the environment of mining areas such as the soil, groundwater, and...  相似文献   
283.
The coliquefaction of coal and polystyrene (PS) in supercritical water (SCW) was carried out in a 50-mL batch stainless steel autoclave reactor, and the effects of the polymer ratio by weight (10–40%), reaction temperature (633.5–703.5 K), and reaction time (30–120 min) were investigated. The main products were analyzed qualitatively by Fourier transform infrared spectroscopy and high-performance liquid chromatography. The results show that polystyrene stimulates coal liquefaction as a hydrogen donor, and the synergistic effects during coliquefaction in SCW were confirmed. The conversion reached a maximum of 62.26% after 60 min at 673.5 K. The phase behavior during coliquefaction was observed in a fused silica capillary reactor using a combined microscope and video recorder system.  相似文献   
284.
Eco-toxicity investigation of polymer materials was considered extremely necessary for their potential menace, which was widely use as mulching materials in agricultural. In this study, polyethylene (PE), polystyrene (PS) and synthetic biomaterials-Ecoflex and cellulose were applying into soil cultivated with two potential indicator plants species: oat (Avena sativa) and red radish (Raphanus sativum). Variety of chemical, biochemical parameters and enzyme activity in soil were proved as effective approach to evaluate polymers phytotoxicity in plant-soil mesocosm. The F-value of biomass, pH, heavy metal and electoral conductivity of Raphanus behaved significant different from T0. Significant analysis results indicated biodegradation was fast in PE than PS, besides, heavy metals were dramatically decrease in the end implied the plant absorption may help decrease heavy metal toxicity. The increase value at T2 of Dehydrogenase activity (0.84 higher than average value for Avena & 0.91 higher for Raphanus), Metabolic Index (3.12 higher than average value for Avena & 3.81 higher for Raphanus) means during soil enzyme activity was promoted by biodegradation for its heterotrophic organisms’ energy transportation was stimulated. Statistics analysis was carried on Biplot PC1 (24.2% of the total variance), PC2 (23.2% of the total variance), versus PC3 (22.8% of the total variance), which indicated phosphatase activity and metabolic index was significant correlated, and high correlation of ammonium and protease activity. Furthermore, the effects were more evident in Raphanus treatments than in Avena, suggesting the higher sensitivity of Raphanus to polymers treatment, which indicate biodegradation of polymers in Raphanus treatment has produced intermediate phytotoxic compounds.  相似文献   
285.
李海燕  吴丽华 《环境科学学报》2021,41(10):4325-4330
以模式生物酿酒酵母为研究对象,采用醋酸铅试纸条法、BIGGY琼脂及qRT-PCR技术检测了不同浓度亚砷酸钠胁迫下H2S产量及产H2S酶编码基因表达的变化,以探讨砷化物对酵母细胞H2S代谢的影响.结果显示,0.5~2 mmol·L-1的亚砷酸钠可诱导酵母细胞内源H2S的产生,且H2S合成相关基因的相对表达量与对照相比均有不同程度的上调.经0.05~0.2 mmol·L-1的外源H2S预处理后,酵母细胞对砷的耐受性明显提高.研究表明,亚砷酸钠可影响酵母细胞H2S代谢,而H2S含量可在一定程度上调控砷对酵母的毒性.  相似文献   
286.
通过浓度梯度驯化,从厌氧污泥中分离到一株酸性大红3R脱色菌M3,根据其形态学特征及16S rRNA基因序列分析,鉴定该厌氧菌株为阴沟肠杆菌(Enterobacter cloacae).同时,研究了该菌株在厌氧静置条件下对酸性大红3R的最适脱色条件.结果表明,菌株脱色的最佳营养源为酵母粉,最适宜脱色条件为酵母粉浓度1%、pH =6.5、温度35 ℃、盐度小于4%,在此条件下,对浓度为100 mg·L-1酸性大红3R溶液厌氧静置培养72 h,脱色率达到98%以上.菌株耐盐性良好,在6% ~8%的盐度下具有较好的脱色效果.分光光谱表明,菌株脱色机制主要为生物降解脱色.毒性试验表明,脱色后的酸性大红3R毒性明显降低.  相似文献   
287.
The present study was conducted to provide a detailed understanding of the variation in cyanobacterial communities of Dongping Lake, which is the final water volume adjusting and storing lake in the east route of the South-to-North Water Diversion Project in China. The spatial and temporal distribution of cyanobacteria was assessed from May 2010 to October 2012 based on monthly samples collected from three stations. Over the 30-month survey, 15 genera and 25 species of cyanobacteria were identified, with cyanobacterial abundance at each monitoring station ranging from undetected to 3.04×107 cells/L, average of 4.27×106 cells/L. The dominant cyanobacterial species were Pseudanabaena limnetica and Aphanizomenon issatschenkoi and not the usual bloom-forming genera such as Microcystis and Anabaena. Cyanobacterial community structure and water quality variables exhibited substantial changes over the period of survey. Redundancy analysis, Pearson correlations, and regression analysis were applied to analyze the relationships among the variables. The results suggested that temperature and chemical oxygen demand were key drivers of the cyanobacterial community composition in Dongping Lake. In addition, the concentration of inorganic nitrogen in the lake had a profound efect on the cyanobacterial abundance as a non-limiting factor in warm periods.  相似文献   
288.
随着畜禽养殖业的发展,养殖废弃物的产生量逐年增加,对环境的影响日益严重,为控制和治理养殖污染物的排放进行环境影响评价成为社会普遍关注的热点。通过对养殖项目环境影响评价工作的编制依据、评价标准的介绍,并以阜康市某规模化肉牛养殖项目为例,对其运营期环境影响进行评价,并提出相应的环境保护措施,为环保部门和企业的管理提供理论依据,并为规模化养殖项目污染的预防治理提供实践经验,最大限度降低项目建设对周围环境的不利影响,推动养殖业的可持续发展。  相似文献   
289.
景观水体污染修复技术对比分析   总被引:1,自引:0,他引:1  
针对景观水体的特点和污染来源,以及修复景观水体水质的物理、化学和生物-生态方法,分析了各种方法的优势和不足,提出景观水体污染控制的关键是控制污染源,修复受损的生态系统,提高水体自净能力,建立良好、健康的水生态系统。  相似文献   
290.
比较中国、韩国土壤修复技术中筛选重金属耐受性植物、重金属超富集植物方法的差异。实际操作中采用哪种方法取决于污染区域的实地状况、修复目标和拟修复时间的长短。对于土壤修复而言,耐受性植物,超富集植物的筛选是非常重要的环节,两国技术方法的差异可以作为制定修复措施的有益参考。  相似文献   
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