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141.
Photolysis (254 nm, 72h) of 1-nitro-2-phenylnaphthalene 1 in methanol gave 2-phenyl-1,4-naphthoquinone-4-monoxime 2, 2,2′-diphenyl-4,4′-binaphth-1,1′-diol 3 and 2,2′-diphenyl-4,4′-binaphth-1,1′-dione 4. Straightforward reactions available to the environment account for the formation of the products: (a) isomerisation of the nitro compound into a nitrite ester followed by either (a) migration of the nitroso group and isomerisation into the oxime 2 or (b) oxidative coupling and solvolysis into the binaphthol 3 and followed by oxidation into the binaphthone 4.  相似文献   
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B. Patel  J. T. Eapen 《Marine Biology》1989,103(2):203-209
Exposure of the tropical arcid blood clam Anadara granosa L., collected from Bombay waters in 1986, to sublethal concentrations of naphthalene (Nap) (5, 10 and 15g Nap ml-1), induced various changes in vital biochemical systems. The condition index (CI) remained largely within the control range, although tissue water content after 96h exposure increased significantly (p<0.001). Glycogen levels appreciably decreased, both in muscles (p<0.001) and digestive glands (p<0.01). AMP activity remained unaltered irrespective of the ambient Nap concentration. ADP levels decreased by more than 20% and ATP levels also decreased significantly (p0.001) by more than 60% with increases in ambient Nap levels from 5 to 15 g ml-1. Lysosomal marker enzymes-arylsulphatase and acid phosphatase-showed various changes. Levels of the former were 10 to 17 times higher than the latter. Total and free arylsulphatase activity in hepatic cells decreased on exposure of clams to 5 and 10g Nap ml-1, but not significantly. However, it was significantly inhibited (p<0.001) towards the upper limits of exposure concentration. The same was also true of acid phosphatase activity. Nicotinamide adenine dinucleotide (NADH2) oxidation of lipochrome showed a dramatic decrease in activity in the range of 37 to 88% over controls with increasing Nap from 5 to 15 g ml-1. Fatty acids also exhibited significant changes in composition with a decrease in polyunsaturated acids and an increase in certain saturated fatty acids. Protein and carbohydrate levels increased significantly (p<0.001) towards upper limits of exposure concentration. Pyruvic acid levels increased significantly by 2 to 6 times over controls on exposure to 5 to 15 g Nap ml-1. Explanation of these changes is attempted in terms of the glycolysis pathway involving pyruvic acid oxidation and oxidative phosphorylation in the electron transport system.  相似文献   
144.
Increased use of farm machinery along with other agricultural inputs has enhanced the production and productivity of Indian farms. Simultaneously, it has also increased occupational health hazards on the farms. Major occupational health hazards are farm related injuries. Very little information is available about the type and nature of agricultural injuries on Indian farms. In the present study, agriculture injuries data were collected for the period 1996–2000 for the Etawah district of Uttar Pradesh in India. It has a total population of 1.4 million while 0.75 million were associated with agricultural activities. The agricultural injuries incidence rate was 0.8 per thousand workers per year in the study area. Out of all agricultural injuries, 9% injuries were fatal. The highest number of injury victims were in the age group of 30–44 years. The highest percentages of injured victims were literate but non-matric. The monetary loss due to agricultural injuries in the study area was estimated to be about US $730,000 per year. To minimize agricultural injuries, development of interventions and trainings needs to be organized at block levels for proper and safe operation of agricultural equipment.  相似文献   
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In the past few decades, governments and international agencies have been placing more emphasis on the improvement of production technique, working conditions and reduction of the toxic emission to the atmosphere. In this context aqueous polyurethane dispersion was synthesized from depolymerised polyethylene terphthalate (PET) waste. 1,4-Butanediol was used in PET depolymerisation. Polyurethane dispersion films were characterized using differential scanning calorimeter, Fourier transform infrared spectroscopy, gel permeable chromatography, etc. Incorporation of PET waste in polyurethane dispersion was an added advantage in waste management and produced better quality polyurethane dispersion.  相似文献   
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The adsorption and mobility of pyrethrins (Pys), the major insecticidal components obtained from the pyrethrum daisy Tanacetum cinerariifolium, and piperonyl butoxide (PBO), a pyrethrum synergist, were determined in soil using batch-equilibrium and reverse-phase thin-layer chromatographic techniques. Two soil management practices were used, soil mixed with yard waste compost (COM) at 50 t acre(-1) on dry weight basis and no-mulch (NM) bare soil. Adsorption isotherm experiments were carried out using known concentrations of Pys (Py-I and Py-II) and PBO mixed with known amounts of COM or NM soil at constant temperature and pressure until equilibrium was attained. Pys and PBO in soil extracts were purified and concentrated using solid-phase extraction cartridges containing C18-octadecyl bonded silica. Pys and PBO residues were quantified using a high-performance liquid chromatograph equipped with a UV detector. Adsorption studies showed that compost amended soil adsorbed more Pys and PBO than native (NM) soil. Py-I adsorption was greater than Py-II and PBO. Adsorption of Pys and PBO to humic and fulvic acids was also studied by reverse-phase thin layer chromatography (RPTLC). Results indicated that humic acid, a significant component of organic matter, reduced Pys and PBO mobility. Pys and PBO mobility decreased as the concentration of humic acid in the mobile phase increased.  相似文献   
150.
Serial cytogenetic observations were made on a group of 273 military recruits who were being trained as welders at Aberdeen, MD. The trainees were being exposed to presumably increased levels of ozone in the course of their welding school experience, and it was the purpose of this study to determine whether or not ozone, at low-to-moderate doses, is capable of inducing chromosomal aberrations in peripheral blood lymphocytes.Previous exposures and the past medical experiences of the trainees were determined by questionnaire, enabling us to obtain a profile on the medical-social characteristics of the study sample. Each welder was to serve as his own control, having a blood sample drawn at the beginning of his twelve week training program, prior to ozone exposure, with two post-exposure bloods being obtained at 6 and 12 weeks after the start of the program.Ozone levels and the levels of the oxides of nitrogen were determined in the immediate area of the welding. The ozone levels were repeatedly found to be negligible, with the nitrogen oxides appearing to be the primary toxic agents involved. For those 165 subjects on whom two blood samples were obtained, and for those 86 on whom all three blood samples were obtained, no statistically significant increases in chromosomal aberrations were found.  相似文献   
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