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131.
In the present experiment the seeds of Cicer arietinum (L.) cv. Uday were inoculated with specific Rhizobium grown in sandy loam soil and were allowed to grow for 15 days. At this stage, the seedlings were supplied with 0, 50, 100 or 150 microM of cadmium in the form of cadmium chloride and sprayed with 0.01 microM of 28-homobrassinolide (HBL) at 30-day stage. The data indicated that plant fresh and dry mass, number of nodules, their fresh and dry mass, leghemoglobin content, nitrogen and carbohydrate content in the nodules, leaf chlorophyll content, nitrate reductase and carbonic anhydrase activities decreased proportionately with the increasing concentrations of cadmium but the content of proline and the activities of catalase, peroxidase and superoxide dismutase increased. The ill effect, generated by cadmium, was overcome if the stressed plants were sprayed with HBL.  相似文献   
132.
Due to the increasingly serious environmental problems presented by waste tires, the feasibility of using elastic and flexible tire-rubber particles as aggregate in concrete is investigated in this study. Tire-rubber particles composed of tire chips, crumb rubber, and a combination of tire chips and crumb rubber, were used to replace mineral aggregates in concrete. These particles were used to replace 12.5%, 25%, 37.5%, and 50% of the total mineral aggregate's volume in concrete. Cylindrical shape concrete specimens 15 cm in diameter and 30 cm in height were fabricated and cured. The fresh rubberized concrete exhibited lower unit weight and acceptable workability compared to plain concrete. The results of a uniaxial compressive strain control test conducted on hardened concrete specimens indicate large reductions in the strength and tangential modulus of elasticity. A significant decrease in the brittle behavior of concrete with increasing rubber content is also demonstrated using nonlinearity indices. The maximum toughness index, indicating the post failure strength of concrete, occurs in concretes with 25% rubber content. Unlike plain concrete, the failure state in rubberized concrete occurs gently and uniformly, and does not cause any separation in the specimen. Crack width and its propagation velocity in rubberized concrete are lower than those of plain concrete. Ultrasonic analysis reveals large reductions in the ultrasonic modulus and high sound absorption for tire-rubber concrete.  相似文献   
133.
Malaysia is in dire need of alternatives to landfilling for solid waste management. Recently, landfills have faced the problems of overfilling, overflowing of leachates leading to pollution of water resources, and uncontrolled dust emissions adversely affecting the local environment. With the rising cost of urbanization coupled with the high rate of waste generation, one possible method of waste treatment that is receiving particular attention by the government is incineration. Incineration of solid waste is rather new in Malaysia, with limited usage in handling small sources of waste generation such as the municipal solid waste (MSW) of resort islands; however, its potential in ameliorating the problems associated with solid waste treatment may make it an attractive alternative to landfill. This article presents the results of test runs conducted to investigate the performance of a locally designed and manufactured rotary kiln incinerator (RKI). The test runs were conducted using MSW collected from the Shah Alam municipality. The combustion efficiency was analyzed by looking at the temperature profiles and chemical species concentrations. To complement the combustion characteristics measurements, predictions of the air flow in the incinerator during the process were also investigated. The overall performance of the RKI suggests that it is suitable for treating MSW.  相似文献   
134.
Atrazine biodegradation by immobilized pure and mixed cultures was examined. A pure atrazine-degrading culture, Agrobacterium radiobacter J14a (J14a), and a mixed culture (MC), isolated from an atrazine-contaminated crop field, were immobilized using phosphorylated-polyvinyl alcohol (PPVA). An existing cell immobilization procedure was modified to enhance PPVA matrix stability. The results showed that the matrices remained mechanically and chemically stable after shaking with glass beads over 15 days under various salt solutions and pH values. The immobilization process had a slight effect on cell viability. With the aid of scanning electron microscopy, a suitable microstructure of PPVA matrices for cell entrapment was observed. There were two porous layers of spherical gel matrices, the outside having an encapsulation property and the inside containing numerous pores for bacteria to occupy. J14a and MC were immobilized at three cell-to-matrix ratios of 3.5, 6.7, and 20 mg dry cells/mL matrix. The atrazine biodegradation tests were conducted in an aerobic batch system, which was inoculated with cells at 2,000 mg/L. The tests were also conducted using free (non-immobilized) J14a and MC for comparative purpose. The cell-to-matrix ratio of 3.5 mg/mL provided the highest atrazine removal efficiency of 40–50% in 120 h for both J14a and MC. The free cell systems, for both cultures, presented much lower atrazine removal efficiencies compared to the immobilized cell systems at the same level of inoculation.  相似文献   
135.
The province of Batman, located in southern Anatolia, has a population of approximately 500,000. To our knowledge, there exists no information regarding the environmental radioactivity in this province. Therefore, gamma activity measurements in soil, building materials and water samples and an indoor radon survey have been carried out in the Batman province. The mean activity concentrations of the natural radionuclides (226Ra, 232Th and 40K) and a fission product (137Cs) were 35 ± 8, 25 ± 10, 274 ± 167 and 12 ± 7 Bq kg???1, respectively, in the soil samples. The concentrations of 226Ra, 232Th and 40K in the selected building materials ranged from 18 to 48 Bq kg???1, 8 to 49 Bq kg???1 and 68 to 477 Bq kg???1, respectively. All the calculated radium equivalent (Raeq) activity values of the building material samples are lower than the limit of 370 Bq kg???1, equivalent to a γ-dose of 1.5 mSv year???1. The activity concentrations of 226Ra, 232Th and 40K in tap waters collected from the study area were determined with mean specific activity concentrations of 42 ± 15, 35 ± 9 and 524 ± 190 mBq L???1, respectively. Indoor radon measurements were made at 95 dwellings in Batman using a CR-39 detector. The radon concentration levels were found to vary from 23 to 145 Bq m???3. The arithmetic mean of the measured radon concentration levels was found to be 84 Bq m???3 with a standard deviation value of 23 Bq m???3. The measurement results obtained in this study did not significantly differ from those taken in other parts of the country. The data generated in this study can be used to determine whether the Batman province is in a normal or high background radiation area and provides a valuable database for future estimations of the impact of radioactive pollution.  相似文献   
136.
The study aimed to determine the hazardous health effects of pesticides exposure in the factory workers by measuring plasma cholinesterase (PChE), pesticides residues, and renal and hepatic biochemical markers. In addition, we also assessed the knowledge, attitudes, and safety practices adopted by the industrial workers. The study was conducted in three different sizes of factories located in Lahore (large), Multan (medium), and Karachi (small) in Pakistan. Total 238 adult males consisting of 184 pesticide industrial workers (exposed group) from large-sized (67), medium-sized (61), small-sized (56) industrial formulation factories, and 54 controls (unexposed) were included in the study. All the participants were male of aged 18 to 58 years. PChE levels were estimated by Ellmann’s method. Plasma pesticides residue analysis was performed by using reverse phase C-18 on high-performance liquid chromatograph and GC with NPD detector. Plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, urea, and gamma glutamyltransferase (GGT) were measured on Selectra E auto analyzer. Plasma and C-reactive protein was analyzed by Immulite 1000. The results revealed a significant decrease in plasma post exposure PChE levels (<30%) as compared to baseline in the workers of small (29%) and medium (8%) industrial units (p?< 0.001). Plasma cypermethrin, endosulfan, imidacloprid, thiodicarb, carbofuran, and methamidophos levels were found to be higher than allowable daily intake. Serum AST, ALT, creatinine GGT, malondialdehyde, total antioxidant, and CRP were significantly raised among the workers of small and medium pesticide formulation factories as compared to large industrial unit and controls (p?< 0.001). The study demonstrated that unsafe practices among small- and medium-sized pesticides industrial workers cause significant increase in pesticide exposure, oxidative stress, and derangement of hepatic and renal function.  相似文献   
137.
The wastewater pollution in industrial areas is one of the most important environmental problems. Heavy metal pollution, especially chromium pollution in the wastewater sources from electroplating, dyeing, and tannery, has affected the life on earth. This pollution can affect on all ecosystems and human health directly or by food chain. Therefore, the determination of total chromium in this study is of great importance. In this study, accurate, rapid, sensitive, selective, simple, and low-cost technique for the direct determination of total Cr in wastewater samples collected from the some Cr electroplating factories in March 2008 by inductively coupled plasma-atomic emission spectrometry has been developed. The analysis of a given sample is completed in about 15 min by this technique applied. As the result of the chromium analysis, the limit of quantification for the total Cr were founded to be over the limit value (0.05 mg L???1; WHO, EPA, TSE 266, and inland water quality classification) as 1,898.78 ± 0.34 mg/L at station 1 and 3,189.02 ± 0.56 mg/L at station 2. The found concentration of total Cr has been determined to be IV class quality water according to the inland water classification. In order to validate the applied method, recovery studies were performed.  相似文献   
138.
This article reports the results of a study that explored whether outdoor recreational areas are sufficient in Istanbul in terms of their surface area and facility characteristics. All the municipalities in 32 subprovinces of Istanbul were sent a survey in 2007 and asked to prepare a list of their outdoor recreational areas including their names, addresses, size, and facilities. All the data collected from the municipalities were used to create a GIS-based inventory by using GIS and remote sensing. As the study revealed, the outdoor recreational areas in Istanbul are far behind meeting the recreational needs of the residents in terms of area per person and facility characteristics. There are 2,470 areas which were dedicated to outdoor recreational activities in Istanbul. Total surface area of all these outdoor recreational areas is 19,2 sq kilometers; this means 1.52 m2 recreational area per person in the city. This value is very low when compared to that of many cities in Europe and USA. As the study also revealed, the majority of outdoor recreational areas in Istanbul are poor in facility. Majority of the existing outdoor recreational areas are small and do not provide the public with many opportunities to engage in different outdoor activities. A more sustainable and efficient recreational plan is needed in Istanbul to meet the various recreational needs of its residents.  相似文献   
139.
The activity concentrations of 226Ra, 232Th, and 40K in lime and gypsum samples used as building materials in Turkey were measured using gamma spectrometry. The mean activity concentrations of 226Ra, 232Th, and 40K were found to be 38 ± 16, 20 ± 9, and 156 ± 54 Bq kg???1 for lime and found to be 17 ± 6, 13 ± 5, and 429 ± 24 Bq kg???1 for gypsum, respectively. The radiological hazards due to the natural radioactivity in the samples were inferred from calculations of radium equivalent activities (Raeq), indoor absorbed dose rate in the air, the annual effective dose, and gamma and alpha indices. These radiological parameters were evaluated and compared with the internationally recommended limits. The experimental mass attenuation coefficients (μ/ρ) of the samples were determined in the energy range 81–1,332 keV. The experimental mass attenuation coefficients were compared with theoretical values obtained using XCOM. It is found that the calculated values and the experimental results are in good agreement.  相似文献   
140.
We study opportunities for CO2 sequestration in geological formations of the state North Rhine Westphalia in Germany. Simulations are performed for evaluating a potential site within the Bunter sandstone formation near the town of Minden in a depth?of around 3,000 m using the numerical simulator TOUGHREACT. Our focus is on three CO2 storage mechanisms: (1) hydrodynamic trapping, (2) dissolution trapping, and (3) mineral trapping. The results show that due to buoyancy the injected CO2 phase initially migrates towards the top of the reservoir and is hydrodynamically trapped beneath the confining layer of the cap rock. Then, the CO2 spreads laterally and dissolves partially in the formation water. The dissolution of CO2 results in an increase of the density of the brine causing a downward migration until it settles after 10,000 years at the bottom of the reservoir. The simulations indicate that after 10,000 years, 15% (17 Mt) from a total of 114 Mt injected CO2 are trapped hydrodynamically, 20% (23 Mt) are trapped by dissolution, and 65% (74 Mt) are fixed in newly formed carbonates such as dawsonite, ankerite, and siderite. Within our study pressure increases near the injection well by a factor of 1.1 which is lower than the upper limit usually accepted in gas storage operations. The mineral reactions cause a net decrease of porosity and in turn a decrease of permeability down to 9% of the initial value in parts of the reservoir.  相似文献   
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