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61.
Lead (Pb) is the most ancient poison known to man. In the present study, amount of accumulation of Pb in liver, kidney, ovary and testes of rain quail was studied using different doses of lead. Spectrophotometric analysis of heavy metal treated organs was carried out to determine the amount of metal accumulation in these organs. LD50 value was 4 ppm. Dose of lead was given in three ranges of low, medium and high. It was observed that testes (< or =6.8 x 10(-6)) mgkg(-1)day(-1) and ovary (< or =7.5 x 10(-6)) mgkg(-1)day(-1), accumulated low amount from different doses when given continuously for 21 days. In contrast to this, liver (< or =9.2 x 10(-6)) mgkg(-1)day(-1) and kidney (< or =9.3 x 10(-6)) mgkg(-1)day(-1) accumulated the maximum amount of metal when treated for the same number of days. This study is quite unique and astonishing as the period for intoxication is short (21 days) as compared to the long ones (91 days and above). Our results show that generally metal accumulation is highest in liver, while it is low in gonad.  相似文献   
62.
Accumulation of Pb, Fe, Cr, Zn, Cd, Ni, Cu and Hg metals in six common lichen species growing on Mangifera indica trees in mango orchard surrounding the north side of the Lucknow city, were analyzed. The study revealed the higher concentration of Pb (3.3 - 15.6 microgg(-1)), Cr (25.6 - 137.5 microgg(-1)), Zn (49.4 - 219.7 microgg(-1)), Cu (10.2 - 66.6 microgg(-1)) and Fe (1748 - 19374 microgg(-1)).  相似文献   
63.
Increase in concentrations of tropospheric ozone (O(3)) is one of the main factors affecting world agriculture production. Tropical countries including India are at greater risk due to their meteorological conditions (high solar radiation and temperature) being conducive to the formation of O(3). The most effective anti-ozonant chemical is N-[2-(2-oxo-1-imidazolidinyl) ethyl]-N-phenylurea or ethylene diurea (EDU). Due to its specific characteristics, EDU has been used in the field as a phytomonitoring agent to assess crop losses due to O(3). Field experiments were conducted on five local cultivars of wheat (Triticum aestivum L. cv HUW234, HUW468, HUW510, PBW343, and Sonalika) grown under natural field conditions in a suburban area of Varanasi, Uttar Pradesh, India during December 2006 to March 2007 to determine the impact of O(3) on their growth and yield characteristics. Mean monthly O(3) concentrations varied between 35.3 ppb and 54.2 ppb at the experimental site. EDU treatment positively affected various growth and yield parameters with difference between cultivars. EDU-treated plants showed increase in shoot and root length, leaf area, absolute growth rate, relative growth rate, and net primary productivity, indicating O(3) induced suppression in growth. EDU treatment was highly significant in different cultivars for total biomass and test weight but not for harvest index. Yield per plant was higher by 25.6%, 24%, 20.4%, 8.6%, and 1.9% in EDU-treated cultivars HUW468, Sonalika, HUW510, HUW234, and PBW343, respectively, than non-EDU-treated ones. These results clearly indicate the sensitivity of all the wheat cultivars to ambient levels of O(3) with cv HUW468 appearing to be most sensitive. The present study also supports the view that EDU has great potential in alleviating the unfavorable effects of O(3) and can be effectively used as a monitoring tool to assess growth and yield losses in areas experiencing elevated concentrations of O(3).  相似文献   
64.
Polyaromatic hydrocarbons (PAHs) utilizing bacteria were isolated from soils of seven sites of Mathura refinery, India. Twenty-six bacterial strains with different morphotypes were isolated. These strains were acclimatized to utilize a mixture of four polycyclic aromatic hydrocarbons, i.e., anthracene, fluorene, phenanthrene, and pyrene, each at 50 mg/L concentration as sole carbon source. Out of total isolates, 15 potent isolates were subjected to 16S rDNA sequencing and identified as a member of diverse genera, i.e., Bacillus, Acinetobacter, Stenotrophomonas, Alcaligenes, Lysinibacillus, Brevibacterium, Serratia, and Streptomyces. Consortium of four promising isolates (Acinetobacter, Brevibacterium, Serratia, and Streptomyces) were also investigated for bioremediation of PAH mixture. This consortium was proved to be efficient PAH degrader resulting in 40–70 % degradation of PAH within 7 days. Results of this study indicated that these genera may play an active role in bioremediation of PAHs.  相似文献   
65.
Fluoride concentration and other parameters in groundwater from 261 villages in Tehsil Kheragarh of District Agra were assessed and attempts were made to observe the relationship between fluoride and other water quality parameters. Of 658 groundwater samples (collected from separate sources) analysed for fluoride, 27% were in the range of 0–1.0 mg/L, 25% in 1.0–1.5 mg/L, 32% in1.5–3.0 mg/L and 16% above 3.0 mg/L. The highest fluoride concentration recorded was 12.80 mg/L. Significant correlation of fluoride with pH, alkalinity, Na, SiO2 and PO4 were observed. Factor analysis was also attempted in order to identify the contributing sources.  相似文献   
66.
Abstract

The degradation of α and β isomers of endosulphan and endosulphan sulphate in four sterilized and non sterilized Indian soils under laboratory conditions was studied. Degradation was found to be more in non‐sterilized as compared to the sterilized soil. The half life of α‐endosulphan, β‐endosulphan and endosulphan sulphate was found to be 136.8, 273 and 301 days in sterilized Alfisol and 55, 256 and 277 days in non‐sterilized Alfisol, respectively. α‐Endosulphan degraded more readily than β‐endosulphan and endosulphan sulphate under both sterilized and non‐sterilized soil conditions.  相似文献   
67.
Scientific concern exists about the toxic effect of dichlorodiphenyldichloroethylene (p, p′-DDE) and lindane on male infertility, and the mechanism underlying male reproductive toxicity of this pesticide remains unanswered. We investigated not only the possible association between the chlorinated pesticide levels and semen quality in nonoccupationally exposed men, but also the probable mode of action using mitochondrial membrane potential (MMP), reactive oxygen species (ROS), lipid peroxidation (LPO), and sperm chromatin structure assay (SCSA). A study in 278 men (21–40 years old) who visited Obstetrics and Gynecology Department, KGMU, Lucknow, for semen analysis was conducted. We performed semen analysis according to the WHO guidelines, while p, p′-DDE and lindane analysis was done by the GLC and LPO by the spectrophotometer, and the sperm mitochondrial status, ROS, and SCSA with the flow cytometer. The questionnaire data showed no significant difference in the demographic characteristics between the two groups, i.e., trying to conceive >1 year and proven fertility. However, a significant difference in the concentration of p, p′-DDE and lindane was observed between the groups. When the subjects were divided among four categories by quartile of exposure, the subjects in the highest quartile showed low sperm motility as compared to the subjects in the lowest quartile. Pearson’s correlation showed a significant negative correlation between semen p, p′-DDE, lindane level, and sperm quality and positive association with the number of cells with depolarized mitochondria, elevation in ROS production and LPO, and DNA fragmentation index (DFI). The findings are suggestive that these toxicants might cause a decline in semen quality, and these effects might be ROS, LPO, and mitochondrial dysfunction mediated.  相似文献   
68.
69.
This paper reports on photocatalytic and adsorptive treatment of a hazardous xanthene dye, Rohdamine B, in wastewater. The photocatalytic degradation was carried out in the presence of the catalyst TiO(2) and the effects of pH, concentration of the dye, amount of TiO(2), temperature and electron acceptor H(2)O(2) on the degradation process were observed. It was found that photocatalytic degradation by TiO(2) is an effective, economical and faster mode of removing Rohdamine B from aqueous solutions. Attempts were also made to utilize activated carbon and rice husk as potential adsorbents to remove Rhodamine B from wastewater. The adsorption studies were carried out at 40, 50 and 60 degrees C, and the effects of pH, temperature, amount of adsorbents, concentration of adsorbate, etc., on the adsorption were measured. On the basis of adsorption data the Langmuir and Freundlich adsorption isotherm models were also confirmed. The adsorption isotherm constants thus obtained were employed to calculate thermodynamic parameters like Gibb's free energy, change in enthalpy and entropy. In order to observe the quality of wastewater COD measurements were also carried out before and after the treatments. A significant decrease in the COD values was observed, which clearly indicates that both photocatalytic and adsorption methods offer good potential to remove Rhodamine B from industrial effluents.  相似文献   
70.
Heavy metal pollution abatement using rock phosphate mineral   总被引:3,自引:0,他引:3  
The low-grade rock phosphate of Jhabua, Madhya Pradesh (India), was investigated for its possible application in the removal of lead, copper, zinc and cobalt ions from aqueous solutions. Effects of contact time, amount of adsorbent and initial concentration of metal ions were studied. Adsorption of heavy metal ions was found to follow the order: Pb2+ > Cu2+ > Zn2+ > Co2+. The probable mechanism of metal ions removal by rock phosphate was found to be by its dissolutions followed by subsequent precipitation.  相似文献   
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