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401.
吕群  吕佳扬 《环境与发展》2020,(1):108-108,110
这些年工业快速发展带动了我国经济快速发展,但是在工业生产过程中产生了大量的废气废液,有效处理这些工业有毒物质是工业发展需要面临的重要问题。本文在此基础上就腐蚀性工业废气治理技术的相关问题作了一定研究,以更好地促进我国经济的协调发展。  相似文献   
402.
Methyl-triclosan (MTCS), a transformation product and metabolite of triclosan, has been widely spread in environment through the daily use of triclosan which is a commonly used anti-bacterial and anti-fungal substance in consumer products. Once entering human body, MTCS could affect the conformation of human serum albumin (HSA) by forming MTCS–HSA complex and alter function of protein and endocrine in human body. To evaluate the potential toxicity of MTCS, the binding mechanism of HSA with MTCS was investigated by UV–vis absorption, circular dichroism and Fourier transform infrared spectroscopy. Binding constants, thermodynamic parameters, the binding forces and the specific binding site were studied in detail. Binding constant at room tempreture (T = 298 K) is 6.32 × 103 L mol−1; ΔH0, ΔS0 and ΔG0 were 22.48 kJ mol−1, 148.16 J mol−1 K−1 and −21.68 kJ mol−1, respectively. The results showed that the interactions between MTCS and HSA are mainly hydrophobic forces. The effects of MTCS on HSA conformation were also discussed. The binding distance (r = 1.2 nm) for MTCS–HSA system was calculated by the efficiency of fluorescence resonance energy transfer. The visualized binding details were also exhibited by molecular modeling method and the results could agree well with that from the experimental study.  相似文献   
403.
城市绿化法是指调整人们在城市绿化活动中产生的社会关系的法律规范总和。它应以保障人的健康和福利、促进城市可持续发展、保障和促进城市绿化事业的发展、保护和改善生态环境、美化生活环境为立法目的。城市绿化法的立法目的既是城市绿化法创制和适用的前提和根本,也是研究城市绿化法的逻辑起点。  相似文献   
404.
秦皇岛市已发现崩塌、泥石流、滑坡、采空塌陷等各类地质灾害点204处,已发生地质灾害111处,占54%。其中,人类工程经济活动与地质灾害形成发展关系密切。保护地质环境与生态环境,可采取加强地灾防治宣传,制止无序群采,禁止山区放牧,科学合理开采地下水,防止海水入侵,在群测群防的基础上,采取必要的工程治理措施。  相似文献   
405.
用微电极测定曝气量对SBR系统中硝化作用的影响   总被引:1,自引:0,他引:1  
为了研究曝气量对硝化作用的影响,实验采用3个相同的SBR装置,分别在曝气量为4、10和16 L/h的条件下处理人工污水,并采用自制的溶解氧、NO3-、NH4+和pH微电极测定了活性污泥絮体内部微元环境中相应基质的浓度。结果表明,曝气量为4 L/h时,活性污泥絮体内存在厌氧微区,NO3--N浓度减小了,发生了反硝化作用;而曝气量为10 L/h和16 L/h时,活性污泥絮体内发生的都是硝化反应,且NH4+-N浓度的减小量、NO3--N浓度的增大量都随着曝气量的增大而增大,pH随着曝气量的增大而减小。  相似文献   
406.
Permafrost wetlands are one of the most sensitive plant communities in response to global warming. Global warming could induce natural plant communities to shift into cooler climate zones, or extirpate. To understand how plant communities in permafrost wetlands are affected by global warming, we examined the patterns of plant species diversity in the 24 permafrost wetlands in the Great Hing’an Mountains along a latitudinal gradient. This gradient was characterized by a northward decline in mean annual temperature (Δ = 3.5°C) and mean annual precipitation (Δ = 38.7 mm). Our results indicated that latitudinal patterns in species diversity existed in the permafrost wetlands. The numbers of family, genus and species, the Gleason index and Shannon-Wiener index for shrubs decreased linearly with decreasing latitude, but increased for herbaceous plants. The latitudinal patterns in species diversity had influenced strongly by temperature. Simple linear regression yielded about 2 decreases in shrub number and 9 increases in herbaceous species number with an increase of mean annual temperature by 1°C, with 0.33 decreases in shrub diversity and 0.29 increases in herbaceous species diversity. If temperature warms 3.7°C by 2100, herbaceous plants might increase in the permafrost wetlands, with species number increasing 48% or 6 times and species diversity increasing 40% or 2 times; and some shrub species might decrease and even disappear in part of the areas with lower latitude, with species number decreasing 50–100% and species diversity decreasing 69–100%. The permafrost wetlands in the Great Hing’an Mountains might continue degenerating and shift northward with global warming over the next century.  相似文献   
407.
Nie Z  Zheng M  Liu W  Zhang B  Liu G  Su G  Lv P  Xiao K 《Chemosphere》2011,85(11):1707-1712
Magnesium production is considered to be one potential source of unintentional persistent organic pollutants (unintentional POPs). However, studies on the emissions of unintentional POPs from magnesium metallurgy are still lacking. Emissions of unintentional POPs, such as polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), polychlorinated naphthalenes (PCNs), hexachlorobenzene (HxCBz) and pentachlorobenzene (PeCBz) are covered under the Stockholm Convention. In this study, these emissions were investigated through a magnesium smelting process. Stack gas and fly ash samples from a typical magnesium plant in China were collected and analyzed to estimate the emissions of unintentional POPs from magnesium metallurgy. Emissions factors of 412 ng TEQ t−1 for PCDD/Fs, 18.6 ng TEQ t−1 for dl-PCBs, 3329 μg t−1 for PCNs, 820 μg t−1 for HxCBz, and 1326 μg t−1 for PeCBz were obtained in 2009. Annual emissions from magnesium metallurgy in China were estimated to be 0.46 g WHO-TEQ for PCDD/Fs and dl-PCBs, 1651 g for PCNs, 403 g for HxCBz and 653 g for PeCBz, respectively.  相似文献   
408.
升金湖自然湿地越冬鹤类生境适宜性变化研究   总被引:2,自引:0,他引:2  
升金湖湿地位于安徽省长江中下游区域,是鹤类重要的越冬地之一,湿地景观的变化影响越冬鹤类的生境质量。研究湿地内越冬鹤类生境变化地对湿地生态恢复有着重要的研究意义。以升金湖国家级自然保护区为研究对象,利用ERDAS软件将1986年到2015年间8个年份冬季的TM影像数据将景观类型分为8种类型,用FRAGSTATS软件计算出各个年份的景观指标。选取干扰程度、食物丰富度、植被覆盖和水文条件4种因子作为影响越冬鹤类生境的主要因子。建立越冬鹤类生境适宜性评价模型,用ArcGIS生成鹤类生境适宜性评价图。用皮尔逊相关分析研究鹤类数量与生境适宜性的相关性。结果表明:升金湖保护区的景观格局变化明显,湿地斑块数量增加,景观的破碎度程度增加,景观斑块差异在逐渐变小,多样性指数和均匀度指数逐渐变大。越冬鹤类生境适宜性综合指数从0.845下降到0.465,总体的生境明显恶化。越冬鹤类的生境适宜性面积从1986年的 13 577.11 hm2 下降到2015年的 7 424.42 hm2,进而导致越冬鹤类数量在1986年到2015年总体呈下降趋势。鹤类数量与生境适宜性呈正相关。 关键词: 生境影响因子;生境适宜性评价模;越冬鹤类;景观格局  相似文献   
409.
上泉水库坝体为浆砌石连拱坝,现被定为病险水库,通过对拱坝结构强度、支墩抗滑稳定的计算分析,采用右坝肩基础、支墩防渗处理、坝体加固处理等措施进行除险加固,并对大坝稳定进行了验算。  相似文献   
410.
臭氧氧化预处理难降解农药废水的研究   总被引:4,自引:2,他引:2  
采用臭氧氧化技术预处理脲类农药生产废水,调节废水pH至弱碱,在此基础上考察废水臭氧氧化预处理的影响因素,得出最佳预处理条件:COD为200 mg/L,初始pH为11.3,臭氧投加量为14.2 mg/L。连续预处理180 min后,可生化性从0.12提高到0.58,说明该项技术可大大提高脲类农药废水的可生化性。  相似文献   
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