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131.
Arsenic is a significant environmental concern worldwide, primarily due to geo physiochemical contamination of drinking water, and a major public health hazard in both developing and developed countries. The present study was aimed to investigate ameliorative effects of curcumin (Cur) against sodium arsenite (SA)-induced toxicity in cultured murine Sertoli cells. The cells were treated with SA (5 μM) and Cur (5 μg/ml and 10 μg/ml) alone or in combination for 12 hr. The SA treatment decreased cell viability, produced oxidative stress, and induced apoptosis as reflected by reactive oxygen species (ROS) generation, loss of mitochondrial transmembrane potential, DNA fragmentation, and apoptotic cells. Moreover, the SA-induced cell cycle arrest in the cells is characterized by a rise in the number of cells in the sub G1 phase of the cell cycle. The Cur was found to be effective in reversing all these arsenic (As)-induced cellular events. Data suggest that Cur modulates As-mediated oxidative stress, apoptosis, DNA fragmentation, and cell cycle arrest through suppression of excessive ROS generation. Evidence indicates that Cur may emerge as a useful protective agent against As-induced Sertoli cells toxicity by inhibiting As-induced damage in testes.  相似文献   
132.
Fluorosis is a serious public health problem in many parts of the world. The generation of reactive oxygen species and lipid peroxidation has been considered to play an important role in the pathogenesis of chronic fluoride toxicity. The present study was undertaken to evaluate the protective effect of Tamarindus indica fruit pulp extract on the collagen content and oxidative stress in liver and kidney of fluoride-exposed rats. The first group served as control. The second group received 200 mg L?1 of sodium fluoride through drinking water. The third and fourth groups received T. indica fruit pulp extract (200 mg kg?1 body weight) alone and along with fluorinated drinking water respectively, daily by gavage for a period of 90 days. At the end of the experiment, blood samples were collected from all groups, and liver and kidney samples were taken concurrently. Levels of malondialdehyde and glutathione and the activities of superoxide dismutase and catalase were evaluated in the liver and kidney of experimental rats. Furthermore, level of hydroxyproline and histological examination of liver and kidney along with serum biochemical parameters were evaluated. In conclusion, fluoride was determined to cause adverse effects in rats, and the supplementation of tamarind to these animals alleviated the adverse effects of fluoride.  相似文献   
133.
Recently the heterogeneous reactions are increasingly recognised as significant in polluted areas. In this work the reactions of gases with solid alkali‐halide crystals at temperatures 200K and 300K were examined by using a recently proposed thermodynamic model (Varotsos et al., 1988) which provides the interconnection of entropy and enthalpy for various processes with well known macroscopic properties of the bulk solid.  相似文献   
134.
Last decade the reactions of gases at solid interfaces were increasingly recognized as significant in polluted marine troposphere and perhaps in remote areas as well. In this study the reactions of gases with solid NaCl at temperatures 200 K and 300 K were examined by using a recently proposed thermodynamical model (Varotsos et al., 1988) which provides the interconnection of entropy and enthalpy for various processes with well known macroscopic properties of the bulk solid.  相似文献   
135.
已二酸生产副产物——混合二元酸的综合利用   总被引:1,自引:1,他引:0  
采用一水合硫酸氢钠作为催化剂,催化己二酸生产副产物——混合二元酸与甲醇反应合成混合二元酸二甲酯。优化工艺条件为:混合二元酸加入量0.1mol,无水甲醇加入量0.5mol,一水合硫酸氢钠加入量4.0g,环己烷加入量20mL,反应时间1.5h。合成混合二元酸二甲酯的酯化反应收率大于97%。经气相色谱检测,产物中酯的质量分数为98.91%。一水合硫酸氢钠可重复使用3次。  相似文献   
136.
头孢噻肟钠生产废渣的综合利用   总被引:3,自引:0,他引:3  
从头孢噻肟钠生产废渣中回收2-硫醇基苯并噻唑合成二硫化二苯并噻唑,DM的收率达23.8%,产品质量达到HGB2-158-61标准,小试表明,方法可行,操作稳定,简便,既减轻了废渣生成的污染,又回收和用途广泛的化工原料,有一定的环境效益和经济效益。  相似文献   
137.
通过批式振荡及溶出模拟实验研究了十二烷基硫酸钠(SDS)、吐温80(TW80)及脂肪醇聚氧乙烯醚硫酸钠(AES)对石油污染含水层介质的脱附净化效果, 考察了振荡时间、SDS浓度、脱附净化流程等对污染物净化效率的影响。结果表明: SDS对石油污染的脱附净化效果优于TW80及AES, 适宜的振荡时间为3 h, 适宜的SDS浓度为4.0 g·L-1; 脱附净化流程实验证实, 按照流程3(首先采用去离子水脱附, 然后采用4.0 g·L-1的SDS溶液进行脱附, 最后采用去离子水脱附)进行脱附净化后, 污染物溶出浓度最低, 推荐流程3作为适宜的脱附净化流程。经上述推荐的实验条件处理后, 含水层介质溶出模拟实验中TPH浓度降低了99%以上, 接近地下水质量标准Ⅳ类限值; 苯浓度降低超过了87%, 低于地下水质量标准Ⅳ类限值, 污染含水层环境及人体健康风险大大降低。基于SDS的脱附净化技术是一种有工程应用前景的石油污染含水层介质修复技术。  相似文献   
138.
主要探究泥浆系统中Fe2+活化过碳酸钠(SPC)降解三氯乙烯(TCE)的效果。通过批次实验研究土壤对TCE的吸附作用,并考察泥浆系统中SPC和Fe2+投加量对TCE去除效果的影响。结果表明,土壤对TCE具有一定的吸附作用;泥浆系统中,土壤含有的有机质越多,TCE去除效果越低;当SPC/TCE摩尔比为5/1~20/1时,SPC投加量对TCE去除影响不明显,TCE去除效果随Fe2+投加量增大而提高。当水土质量比为30/1,TCE初始浓度为20 mg/L时,SPC/Fe2+/TCE最优摩尔比为10/30/1,此时TCE最终去除率达到97.5%。综上所述,Fe2+活化过碳酸钠降解三氯乙烯快速高效,为应用于实际场地修复提供有效的理论依据。  相似文献   
139.
以木质素磺酸钠(LS-Na)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酸(AA)为原料,采用微波辐射法,通过接枝共聚反应合成了生物质LS-g-PAMPS/AA水凝胶吸附剂,利用FTIR分析了水凝胶的结构。研究了吸附剂用量、染料初始浓度、吸附时间对亚甲基蓝(MB)染料的吸附性能的影响,结果显示,在MB初始浓度为1 000 mg/L,吸附剂为0.1 g时,吸附量和吸附率分别达1 914 mg/g和95%。平衡吸附数据满足Langmuir吸附等温模型,吸附动力学曲线较好地符合准二级动力学反应模型。木质素水凝胶对MB染料废水具有显著的吸附效果,可以作为阳离了染料废水处理用的生物质吸附剂。  相似文献   
140.
通过构建光合藻微生物燃料电池(PAMFC),研究了分别以乙酸钠或葡萄糖作为唯一电子供体时,对PAMFC的产电性能及其中小球藻生长的影响。结果表明,在外电阻为1 000 Ω时,以乙酸钠为电子供体的PAMFC最大输出电压是285 mV、最大输出功率为3.42 mW/m2;以葡萄糖为电子供体的PAMFC最大输出电压是247 mV、最大输出功率为2.68 mW/m2。同时,分别以乙酸钠或葡萄糖为电子供体的PAMFC中小球藻生长所达到的生物量分别是1.8 g/L和1.26 g/L,而对照组中的小球藻生物量仅为0.83 g/L。简单电子供体的电池性能优于复杂电子供体,同时更能促进PAMFC中阴极光合藻生长,使电池阴极得以固定更多阳极所排放的二氧化碳。  相似文献   
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