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Introduction. Shoulder disorders are one of the most prevalent musculoskeletal disorders among carpet weavers. The most important cause of these disorders is muscle fatigue. The aim of the present study is to investigate the effect of carpet weaving characteristics on upper trapezius (UTr) muscle fatigue during a task cycle. Method. In this cross-sectional study, 9 women and 3 men participated. During an 80-min cycle of carpet weaving, a times-series model was applied to assess electromyography amplitude and frequency changes. Result. According to the joint analysis of electromyogram spectrum and amplitude method, the participants experienced 0% force decrease, 0.9% recovery, 18% force increase and 72% fatigue in the left UTr. Furthermore, the rates of force decrease, recovery, force increase and fatigue in the right UTr were 18%, 18%, 18% and 45%, respectively. Fatigue in the right and the left UTr was reported to be the dominant state during one carpet weaving task cycle. Conclusion. Task cycle appears to have a significant impact on UTr fatigue in participants, and UTr fatigue can be considered a serious risk factor in shoulder musculoskeletal disorders. Hence, further studies should focus on better workstations and work–rest periods during various subtasks.  相似文献   
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Healthcare waste management (HCWM) options are inconsistent in Bangladesh. One of the first critical steps in the process of developing a reliable waste management plan requires a comprehensive understanding of the quantities and characteristics of the waste that needs to be managed. This study took into consideration both the quantity and quality of the generated waste to determine the generation rates and physical properties of healthcare waste (HCW) in Chittagong Medical College Hospital (CMCH) and also to estimate the amount of infectious and non-infectious waste generated in different wards. CMCH, the second largest hospital in Bangladesh, comprises 34 wards, 12 of which were selected randomly. Waste materials were collected from these wards and then segregated and weighed. Waste generation per day was found to be 73.22 kg/ward, 1.28 kg/bed and 0.57 kg/patient. A total of 2490 kg of HCW was produced each day in CMCH (37% being infectious and the rest being non-infectious waste). Infectious waste was 27.07 kg per ward, 0.47 kg per bed and 0.21 kg per patient and the non-infectious waste was 46.15 kg per ward, 0.81 kg per bed and 0.36 kg per patient per day. HCW comprised eight categories of waste materials with vegetable/food waste being the largest component (50.21%) and varied significantly (P < 0.05) among the 12 different wards studied. The greatest amount of HCW was recorded (154 kg) in Orthopaedics followed by 96.66 kg in the Medicine Unit-3 and the smallest amount was recorded in Casualty (8.79 kg). The amount of HCW was positively correlated with the number of occupied beds (rxy = 0.79, P < 0.01). There is no structured form of medical waste treatment in CMCH and most waste materials are dumped in open areas for natural degradation or re-sold by scavengers. It is essential to develop a national policy and implement a comprehensive action plan for HCWM that will provide environmentally sound technological measures to improve HCWM in Bangladesh.  相似文献   
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Environmental Science and Pollution Research - Membrane technologies are used intensively for desalination and wastewater treatment. Water filtration using ceramic membranes exhibited high...  相似文献   
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Vehicular air pollution is a mounting health issue of the modern age, particularly in urban populations of the developing nations. Auto-rickshaws are not considered eco-friendly as to their inefficient engines producing large amount of particulate matter (PM), thus posing significant environmental threat. The present study was conducted to ascertain the cytotoxic, phytotoxic, and mutagenic potential of PM from gasoline-powered two-stroke auto-rickshaws (TSA) and compressed natural gas-powered four-stroke auto-rickshaws (FSA). Based on the increased amount of aluminum quantified during proton-induced X-ray emission analysis of PM from TSA and FSA, different concentrations of aluminum sulfate were also tested to determine its eco-toxicological potential. The MTT assay demonstrated significant (p?<?0.001) dose-dependent cytotoxic effects of different concentrations of TSA, FSA, and aluminum sulfate on BHK-21 cell line. LC50 of TSA, FSA, and aluminum sulfate was quantified at 16, 11, and 23.8 μg/ml, respectively, establishing PM from FSA, a highly cytotoxic material. In case of phytotoxicity screening using Zea mays, the results demonstrated that all three tested materials were equally phytotoxic at higher concentrations producing significant reduction (p?<?0.001) in seed germination. Aluminum sulfate proved to be a highly phytotoxic agent even at its lowest concentration. Mutagenicity was assessed by fluctuation Salmonella reverse mutation assay adopting TA100 and TA98 mutant strains with (+S9) and without (?S9) metabolic activation. Despite the fact that different concentrations of PM from both sources, i.e., TSA and FSA were highly mutagenic (p?<?0.001) even at lower concentrations, the mutagenic index was higher in TSA. Data advocate that all tested materials are equally ecotoxic, and if the existing trend of atmospheric pollution by auto-rickshaws is continued, airborne heavy metals will seriously affect the normal growth of local inhabitants and increased contamination of agricultural products, which will amplify the dietary intake of the toxic elements and could result in genetic mutation or long-term health implications.  相似文献   
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Soil physical and chemical properties were quantified to assess soil organic carbon (SOC) density (t ha-1) and SOC CO2 mitigation (t ha-1) under six forest strata Cedrus deodara (closed) (S1), Cedrus deodara (open) (S2), Abies pindrow-Picea smithiana (closed) (S3), Abies pindrow-Picea smithiana (open) (S4), Pinus wallichiana (closed) (S5) and Pinus wallichiana (open) (S6) in the southern region of Kashmir Himalayas India. Lowest average bulk density (Db) of 0.95 was found same in S3 (σ?±?0.07) and S5 (σ?±?0.09) and highest Db (1.08) was observed in S2 (σ?±?0.05). A relatively higher coarse fraction was observed in all the six strata ranging from 19.23 (SD?±?4.66) in S3 to 29.37 (σ?±?6.12) in S6. Soil pH ranged from 6.09 (σ?±?0.64) in S4 to 6.97 (σ?±?0.53) in S2. The region under biotic interference has observed significant deforestation and degradation in the past two decades leading to lower SOC% values compared to other studies in the adjoining regions of Indian Himalayas and temperate coniferous forests in general. SOC% values were observed to range from 1.03 (σ?±?0.22) in S2 to 2.25 (σ?±?0.23) in S3. SOC density ranged between 25.11 (σ?±?5.41) t ha-1 in S2 and 51.93 (σ?±?5.24) t ha-1 in S3. SOC CO2 mitigation density was found highest 190.59 (σ?±?19.23) t ha-1 in S3 and lowest 92.16 (σ?±?19.86) t ha-1 in S2. A significant variation was observed in SOC density within strata. SOC density values in closed strata in general exceed to those in open strata. Primary results indicate that the average SOC stock for all the strata is low due to continuous biotic pressure in the last two decades making it a potential region for SOC buildup under plus options of REDD + (Reducing emissions from deforestation and forest degradation) which includes conservation, sustainable management of forests and enhancement of forest carbon (C) stocks.  相似文献   
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ABSTRACT: A test of the suitability of subsurface drip irrigation (SDI) for alfalfa (Medicago sativa L) compared to a sprinkler, was conducted on a Kansas producer's field where the soil is loam. The treatments included drip tape spacing of 60, 40, and 30 inches placed at depths of 18 and 12 inches. A nearby plot irrigated by a center pivot sprinkler was seeded to alfalfa and used for comparison. Seedling emergence and yield were adversely affected at 60 inch spacing, while the depth of placement of drip tapes (18 and 12 inches) showed no effect on yield. The site served for education and allowed comparison between SDI tape spacing and center pivot system.  相似文献   
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