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721.
Yanfeng Wang Wei Chen Xiao Chen Huajun Feng Dongsheng Shen Bin Huang Yufeng Ji Yuyang Zhou Yuxiang Liang 《环境科学学报(英文版)》2018,30(3):347-355
Cd S/Mo S_2,an extremely efficient photocatalyst,has been extensively used in hydrogen photoproduction and pollutant degradation.Cd S/Mo S_2can be synthesized by a facile one-step hydrothermal process.However,the effect of the sulfur source on the synthesis of Cd S/Mo S_2via one-step hydrothermal methods has seldom been investigated.We report herein a series of one-step hydrothermal preparations of Cd S/Mo S_2using three different sulfur sources:thioacetamide,L-cysteine,and thiourea.The results revealed that the sulfur source strongly affected the crystallization,morphology,elemental composition and ultraviolet(UV)–visible-light-absorption ability of the Cd S/Mo S_2.Among the investigated sulfur sources,thioacetamide provided the highest visible-light absorption ability for Cd S/Mo S_2,with the smallest average particle size and largest surface area,resulting in the highest efficiency in Methylene Blue(MB)degradation.The photocatalytic activity of Cd S/Mo S_2synthesized from the three sulfur sources can be arranged in the following order:thioacetamideL-cysteinethiourea.The reaction rate constants(k)for thioacetamide,L-cysteine,and thiourea were estimated to be 0.0197,0.0140,and 0.0084 min~(-1),respectively.However,thioacetamide may be limited in practical application in terms of its price and toxicity,while L-cysteine is relatively economical,less toxic and exhibited good photocatalytic degradation performance toward MB. 相似文献
722.
选取CaO作为吸附剂,探究了不同燃烧温度下添加CaO对重金属元素在燃煤灰渣中富集效果的影响规律。实验结果表明:添加CaO对重金属元素Cr未起到富集作用,而对Mn,Ni,Cu,Zn,As,Cd,Pb 7种重金属元素的富集效果显著;随燃烧温度的升高,CaO对各赋存形态的Mn,Ni,Cu,Zn,As的富集效果先变好而后变差,对各赋存形态的Cd和Pb的富集效果越来越好;CaO添加比(预处理后的CaO颗粒与预处理后的原煤的质量比)越大,CaO对Mn,Ni,Cu,Zn,As,Cd,Pb的富集效果越好,燃烧温度为850℃时的最佳CaO添加比为4%。 相似文献
723.
高效重金属捕集剂EDTC的结构表征及对酸性络合铜的去除特性研究 总被引:1,自引:1,他引:0
以乙二胺和二硫化碳为反应物,无水乙醇和去离子水的混合溶液为溶剂,制备了一种巯基类重金属捕集剂N,N-双(二硫代羧基)乙二胺(EDTC),采用紫外光谱、红外光谱和元素分析对其结构进行表征,重点研究了其对EDTA络合铜、柠檬酸络合铜和酒石酸铜3种酸性模拟络合铜的去除性能及螯合沉淀物的溶出特性,并探讨了EDTC脱除络合铜的机理.研究结果表明,处理50 mg·L-1的含铜废水,p H值范围为3~9,EDTC投加量为mEDTC/mCu=8(质量比),反应时间3 min,PAM投加量为1 mg·L-1,此时出水Cu2+浓度均低于0.25 mg·L-1,去除率达到99.5%以上.螯合沉淀物在弱酸性和弱碱性条件下很稳定,不易产生二次污染.红外光谱图分析结果表明,EDTC与Cu会发生螯合反应,即EDTC直接脱出络合铜中Cu2+,并与Cu2+生成难溶的螯合产物EDTC-Cu,进而有效地去除废水中Cu. 相似文献
724.
为掌握长春市主城区净月大学城区PM2.5和PM10质量浓度的空间分布特征,选择了8处室外环境空间,使用YT-HPC3000 C型主动采样激光粉尘仪,对各样点进行了质量浓度监测。结果表明,与区域内室外8处样点的PM10质量浓度,以轻轨站处为最高,其他7处样点均好于二级标准;室内4处样点的PM2.5和PM10的质量浓度,食堂均未达标,其他3处样点均达标。在室内各样点,PM2.5与PM10的浓度空间分布呈现随高度升高而降低的趋势;在室外各样点,PM2.5与PM10的浓度分布与其所处垂向位置无明显相关关系。 相似文献
725.
在考虑东中西区域间技术集合差异的基础上,采用SBM-Undesirable和Meta-frontier函数模型测算区域问能源效率.同时采用共同技术比率定量分析了各省区能源利用的技术差距,并从生产技术和管理两个维度分析能源利用无效率来源.发现中国能源效率整体存在较大改善空间且呈现出东-西-中递减格局.各省区在共同前沿边界下能源效率技术水平均不大于群组前沿边界下的能源效率,且东-西-中三大地区能源效率的无效率来源各有不同,需要因地制宜制定不同提升策略. 相似文献
726.
727.
运用探地雷达进行加油站埋地罐区油品泄漏检测,先后对8座加油站进行了埋地罐区泄漏测试,发现某加油站埋地罐区的疑似泄漏区域,并对疑似泄漏区域进行了验证确认。 相似文献
728.
Yi H. Liu Jian Chen Chun M. Wang Yi R. Guo Xiao Liang Guo N. Zhu 《Journal of environmental science and health. Part. B》2013,48(6):540-546
A new method for specific antibody production was developed using antibody (Ab)-pesticide complex as a unique immunogen. Parathion (PA) was the targeted pesticide, and rabbit polyclonal antibody (Pab) and mouse monoclonal antibody (Mab) were used as carrier proteins. The Ab-PA complexes were generated by conjugating the two antibodies with an excessive dosage of PA. It was shown that the sensitivity of homologous enzyme-linked immunosorbent assay (ELISA) using the new antibodies was similar to that using original antibodies. However, the new mouse Pab had not only similar positive recognizing spectrum as the original Mab, but also a significantly improved sensitivity in heterologous ELISA when some recognizable competitors were applied. IC50 value of ELISA based on a combination of the new mouse Pab and hapten 9 was 0.24 ng/mL, which was 445.54 times as that of the homologous ELISA. An Ab-pesticide complex may be a suitable alternative immunogen for producing highly specific antibody to improve the immunoassay sensitivity. 相似文献
729.
<正>地处祖国西南边陲的云南省,气候变幻异常,自然灾害频发。特别是每年进入汛期以来,全省大部分地区都会出现持续性的强降雨,导致严重的洪涝、泥石流、山体滑坡等重大自然灾害发生,造成重大人员伤亡和财产损失。其中,德宏、怒江、保山、临沧、红河、版纳六个州市灾情尤为严重。据有关资料记载:灾情最严重的2004年,全省3800万人口,就有1400多万受灾,占全省 相似文献
730.
Shiliang Su Rui Xiao Xiangyang Xu Zhonghao Zhang Xiaoya Mi Jiaping Wu 《Regional Environmental Change》2013,13(1):77-89
This study employed spatial regression to analyze the determinants of dissolved oxygen (DO) and nutrients in the Qiantang River, China. Determinants of their spatial patterns in 1996 and 2003 as well as their dynamics during this time period were characterized at sub-basin and 500-m riparian buffer scales. Results indicated that the determinants differed by variable and by scale. Built-ups, farmland, water body, population density and gross domestic product were positive indicators for nutrient pollution and hypoxia, while distance to river source and forest were negative indicators. Higher slope variability indicates more DO and nutrients. In addition, built-up increases that were accelerated by population growth and economic development accounted for DO and nutrients dynamics to a large extent. This study highlighted that incorporation of spatial autocorrelation into regression was not only a methodological advantage but also a promising management tool. 相似文献