首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   17篇
  免费   0篇
废物处理   1篇
基础理论   5篇
污染及防治   3篇
评价与监测   8篇
  2022年   1篇
  2017年   1篇
  2016年   1篇
  2010年   2篇
  2007年   3篇
  2003年   1篇
  2002年   3篇
  2001年   1篇
  1997年   1篇
  1994年   2篇
  1992年   1篇
排序方式: 共有17条查询结果,搜索用时 15 毫秒
1.
The present study deals with the assessment of industrial water of an electronic component manufacturing unit with electroplating and its subsequent effects on soil and plants receiving the effluent. The physico-chemical parameters of the effluent samples showed higher value than that of ground water. The treated effluent was within the permissible limit. Microtox test was conducted and determined the degree of toxicity of untreated, treated effluents as well as the water sample collected at effluent discharge point of receiving river (confluence point). The physico- mechanical parameters of the soil samples were not changed due to irrigation of the treated effluent, but the concentration of metals were comparatively higher than the control soil. Higher accumulation of metals was found in the plant parts in naturally growing weeds and cultivated crop plant irrigated with treated effluent. Elevated accumulation of metals in Eichhornia crassipes and Marsilea sp. growing along the effluent channel has been identified as a potential source of biomonitoring of metals particularly for Cu and Ca and can be utilised for the removal of heavy metal from wastewater.  相似文献   
2.
Occupational exposure to benzene was measured in two gasoline marketing terminals and five major refineries in Singapore. A total of 280 workers were monitored over two years. This assessment was carried out with two primary objectives: (1) To find out the extent of occupational exposure to benzene in the petroleum industry in Singapore, (2) To identify suitable biomarkers for monitoring of low levels of benzene exposure. The exposure was measured in five different categories of petroleum and petrochemical workers, i.e., truck drivers, despatch assistant, process operators, oil movements operators and laboratory technicians. The results revealed wide variations in exposure, from 0.01 to 13.6 ppm for personal time weighted average (TWA) exposure over the whole workshift. The exposure of truck drivers appeared to be the highest, with geometric mean (GM) of 1.98 ppm (ranged from 0.25 to 13.6 ppm). The average benzene exposure for process operators was relative low with a GM of 0.04 ppm. Lowest benzene exposure was found in the laboratory technicians, with a GM of 0.02 ppm. As cigarette smoking is known to affect metabolism of benzene, data analyses on the relationships with environmental exposure were conducted only on the 190 nonsmokers. The results showed that urinary trans, trans-muconic acid (ttMA), unmetabolized benzene in urine (UBZ) and benzene in blood (BBZ) were better biomarkers for low level benzene exposure as compared to urinary phenolic metabolites in urine, such as hydroquinone, phenol and catechol.  相似文献   
3.

An improved approach based on the use of iron-doped polymeric beads (IPB) as Fenton catalyst in the pretreatment and biomass-doped polymeric bead (BPB) in the biological oxidation has been reported for the removal of different aromatic mixtures present as pollutants in the aqueous solutions. Degradation has been investigated at fixed loading of IPB as 2.5 % weight basis and varying loading of hydrogen peroxide so as to understand the effect of oxidant loading on the extent of degradation. It has been observed that the maximum removal efficiency as 75.5, 81.4, and 59.1 % was obtained for the benzene-toluene-naphthalene-xylene (BTNX), benzene-toluene-ethylbenzene-xylene (BTEX), and benzene-toluene-naphthalene-p-nitrophenol (BTNp-NP) mixtures, respectively, at a 40-min pretreatment and optimum pH of 3.5. The biodegradability index was also observed in the favorable range of 0.4 to 0.5 after the pretreatment at optimum H2O2 loading of 1.5 g L−1. Maximum COD removal efficiency of 99.2, 99.3, and 99.6 % was obtained using the biological oxidation treatment for 40 h for the case of BTNX, BTEX, and BTNp-NP mixtures, respectively. Analysis of kinetic models revealed that degradation followed three distinct stages based on fitting of the three-stage model and BPB was found to be more efficient as compared to the primary activated sludge (PAS) and modified activated sludge (MAS). Reusability studies confirmed that both IPB and BPB were effective over many cycles giving stable performance during degradation without leaching of Fe3+ ions into the solution.

  相似文献   
4.
The efficacy of Common Effluent Treatment Plant (CETP) based on activated sludge process employed for treatment of tannery effluent was analyzed for the efficiency to reduce chromium and other contaminants. Physico-chemical parameters of treated effluent were found within permissible levels of statutory limits. A significant reduction in COD and BOD levels were achieved during the course of treatment in CETP. A reduction of 98.46%, 87.5%, and 96.15% in bacterial counts especially in pathogens like Escherichia coli, Vibrio spp., and Pseudomonas spp. were observed after treatment. Pathogens were not detected in the dried sludge. Complete elimination of fecal streptococci was observed in treated effluent. Around 10.8% of microbial isolates from the effluent showed ability to reduce chromate >90%. In treated effluent chromium level was 5.48 mg/L, which exceeds the statutory limit of Indian standards. Cleaner production options to reduce chromium levels before discharging into water bodies is discussed.  相似文献   
5.
In this study, strains that are capable of bioaccumulating Cr(VI) were isolated from treated tannery effluent of a common effluent treatment plant. The Cr(VI) concentration in this treated effluent was 0.96 mg/l, much above the statutory limit of 0.1 mg/l for discharge of industrial effluents into inland surface waters in India. In addition to the bioaccumulation, biosorption capabilities of living and dead cells were analysed. Two strains, identified as Bacillus circulans and Bacillus megaterium were able to bioaccumulate 34.5 and 32.0 mg Cr/g dry weight, respectively and brought the residual concentration of Cr(VI) to the permissible limit in 24 h when the initial concentration was 50 mg Cr(VI)/l. Our experimental design accounts for initial as well as final residual concentration of heavy metal while selecting heavy metal accumulating strains during batch studies. Biosorption of Cr(VI) was shown by B. megaterium and an another strain, B. coagulans. Living and dead cells of B. coagulans biosorbed 23.8 and 39.9 mg Cr/g dry weight, respectively, whereas, 15.7 and 30.7 mg Cr/g dry weight was biosorbed by living and dead cells of B. megaterium, respectively. Biosorption by the dead cells was higher than the living cells. This was due to prior pH conditioning (pH 2.5 with deionized water acidified with H2SO4) of the dead cells.  相似文献   
6.
Simple microbial test comprising H2S paper strip test,presence-absence (PA) test, and fluorogenic brila broth (BB)test performed directly at 44.5 °C were evaluated andcompared with the standard most probable number (MPN) method fordetection of fecal coliforms in 173 drinking water sources. BBand PA test were comparable with standard MPN method, whereas,poor compliance was noted for H2S test. PA test whencompared with standard MPN test only 15%; disagreement wasdetected, whereas, highest disagreement of 40%; was observed incase of H2S test. BB test was found to be highly sensitiveas only 7.8% disagreement with that of standard MPN test wasfound. Three hundred cultures obtained from positive tests wereidentified in order to evaluate the specificities of test usedin detection of fecal indicator Escherichia coli. BB testwas also found highly specific in detection of indicatororganism as compared to PA and H2S test. Among theorganisms isolated from BB test 84.4%; of them were identifiedas E. coli as compared to 43.4 and 33.3 in PA and H2Stest, respectively. The low incidence of recovery of E.coli (18.1%) for the standard MPN method places doubt on thevalidity of its application in tropical areas. The result ofthis investigation suggest that BB performed directly at 44.5 °C could be suitable cost effective test to assess themicrobiological quality of drinking water in India and other tropical countries.  相似文献   
7.
Fifty seven isolates of thermotolerant E. coli were recovered from 188 drinking water sources, 45 (78.9%) were typable of which 15 (26.3%) were pathogenic serotypes. Pathogenic serogroup obtained were 04 (Uropathogenic E. coli, UPEC), 025 (Enterotoxigenic E. coli, ETEC), 086 (Enteropathogenic E. coli, EPEC), 0103 (Shiga-toxin producing E. coli, STEC), 0157 (Shiga-toxin producing E. coli, STEC), 08 (Enterotoxigenic E. coli, ETEC) and 0113 (Shiga-toxin producing E. coli, STEC). All the pathogenic serotypes showed resistance to bacitracin and multiple heavy metal ions. Resistance to streptomycin and co-trimazole was detected in two strains whereas resistance to cephaloridine, polymixin-B and ampicillin was detected in one strain each. Transfer of resistances to drugs and metallic ions was observed in 9 out of 12 strains studied. Resistances to bacitracin were transferred in all nine strains. Among heavy metals resistance to As3+ followed by Cr6+ were transferred more frequently.  相似文献   
8.
Bioaccumulation and biosorption of various nickel salts by Serratia marcescens (NCIM 2078) were investigated Biosorption of nickel was found maximum for the nickel nitrate and nickel chloride as 28.08 and 25.51 mg-1 nickel was obtained in dry biomass of S. marcescens, respectively. The possible role of pigment prodigiosin in uptake of nickel is discussed.  相似文献   
9.
Water samples from 30 rivers in northern and north-eastern hilly states of India were analysed for bacteriological and physicochemical parameters along with metals and pesticide residues. It was found that 34% of samples had >50 coliforms/100 ml, while 24% of samples demonstrated >50 thermotolerant (faecal) coliforms/100 ml. Among the metals, iron was found to be above maximum permissible limits in the rivers of all the states, while manganese was found to be above the maximum permissible limit in the rivers of Tripura and some northern states. Zinc, lead, nickel, chromium, copper, cobalt and cadmium plus physicochemical parameters and residual pesticides, however, were within their maximum permissible limits.  相似文献   
10.
A field experiment was conducted to study the impact of Sulphur(S) and Phosphorus (P) on yield, nutrient status of soil and their contents in pigeonpea (Cajanus cajan) during the year 2008-2009. Seven treatments were studied in Factorial Randomized Block Design with three replications. The treatment combinations were derived from three levels of sulphur (0, 20 and 40 kg S ha(-1)) and four levels of phosphorus (0, 25, 50 and 75 kg ha(-1)). The experimental soil was medium black, slightly calcareous, clay in texture and slightly alkaline in reaction. The results indicated a significant increase in grain yield (14.81 q ha(-1)) and straw yield (41.26 q ha(-1)) of pigeonpea after 20 kg S ha(-1) and 50 kg P2O5 ha(-1) treatment with common dose of nitrogen @ 30 kg ha(-1). The increase in grain and straw yield was 102.77 and 52.87% as compare to higher over control. Maximum number of pods plant(-1), maximum number of grains pod and test weight by this treatment was also observed as compared to control. Application of S and P improved soil fertility status and S alone did not influence P availability. Hence, in order to maintain the fertility status of the soil at high level, combine application of 20 kg S ha(-1) with 50 kg P2O5 ha(-1) is essential. The residual fertility status of soil is advocated for rainfed pigeonpea crop grown on vertisol in Vidarbha region.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号