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521.
用环境同位素研究灰场灰水对周围地下水的影响   总被引:11,自引:0,他引:11       下载免费PDF全文
应用环境同位素理论,根据燃煤火电厂灰场灰水中的氢、氧、硫同位素与天然地下水中的氢、氧、硫同位素存在的差异,建立了鉴别天然地下水和灰水的方法,并研究了灰场灰水对周围地下水的影响程度、范围和主要途径,为今后开展灰场对周围地下水影响的研究,确定地下水是否受到污染,提供了一条新的研究途径.   相似文献   
522.
沸石的投加,降低了污泥的比阻,提高了污泥的水通量,改善了污泥膜分离效果,钝化了污水中的重金属,吸附了污水中的难降解有机物,但同时降低了污泥的体积压缩性能,改变了污泥的成分,显著增加了Si、Al、K、Na等无机组分,并对污泥的资源化途径带来了影响。  相似文献   
523.
周亮  凌宝香 《环境技术》2005,24(3):30-32,44
通过对多种化学药剂处理印染废水原水和只经过生化的印染废水出水的试验研究,找出了药剂在各自最佳的反应条件下的处理成本和处理效果。结果表明,处理吨水成本最低而又处理效果较好的药剂为A料和石灰的组合,它对印染废水的原水色度、CODCr的处理效果可达85%、46%,对生化出水色度、CODCr的处理效果可达80.3%、47%。  相似文献   
524.
聚合物驱采出水处理工艺研究   总被引:7,自引:0,他引:7  
聚合物驱油技术在大庆油田得到广泛应用,由于采出水粘度大、油珠粒径小,其处理难度大于油田常规水驱采出水。通过对聚合物驱采出水的特性分析,并在现场分别进行了以横向流除油器(串联DTH聚结器)和水力旋流器为主体的工艺试验。其工艺参数分别为:横向流除油器和DTH聚结除油器的处理量均为85 m3/h,有效停留时间为2.4 h。过滤器为石英砂、磁铁矿双层滤料,处理量为20 m3/h,过滤周期24 h,反冲洗时间为15 min,一次和二次过滤的滤速分别为12 m3/h和8 m3/h。试验结果表明:两种工艺均可代替现有的沉降过滤工艺处理聚合物驱采出水。  相似文献   
525.
李娟 《环境与发展》2020,(1):226-227
污染物处置现场是制造业环境合规管理的前沿阵地,做好相关管理在实现企业的合规义务的同时有助于企业降低成本及提升社会责任形象。基于此,本文针对制造业污染物处置现场的问题,结合5S的管理,对5S管理进行了概述,同时从提升现场合规管理、降低安全环境光风险、有效控制跑冒滴漏及管理成本四个方面对制造企业污染物处理推广5S管理的必要性进行了分析,再基于这些必要性给出了企业污染物处置推广5S管理的一些重要举措,以期为实际的企业管理提供指导。  相似文献   
526.
A microcosm laboratory experiment was conducted to determine the impact of biological reworking by the ragworm Nereis diversicolor on the redistribution of particle-bound radionuclides deposited at the sediment-water interface. Over the course of the 40-day experiment, as much as 35% of a 137Cs-labelled particulate tracer deposited on the sediment surface was redistributed to depths of up to 11 cm by the polychaete. Three different reworking models were employed to model the profiles and quantify the biodiffusion and biotransport coefficients: a gallery-diffuser model, a continuous sub-surface egestion model and a biodiffusion model. Although the biodiffusion coefficients obtained for each model were quite similar, the continuous sub-surface egestion model provided the best fit to the data. The average biodiffusion coefficient, at 1.8 ± 0.9 cm2 y−1, is in good agreement with the values quoted by other workers on the bioturbation effects of this polychaete species. The corresponding value for the biotransport coefficient was found to be 0.9 ± 0.4 cm y−1. The effects of non-local mixing were incorporated in a model to describe the temporal evolution of measured 99Tc and 60Co radionuclide sediment profiles in the eastern Irish Sea, influenced by radioactive waste discharged from the Sellafield reprocessing plant. Reworking conditions in the sediment column were simulated by considering an upper mixed layer, an exponentially decreasing diffusion coefficient, and appropriate biotransport coefficients to account for non-local mixing. The diffusion coefficients calculated from the 99Tc and 60Co cores were in the range 2-14 cm2 y−1, which are consistent with the values found by other workers in the same marine area, while the biotransport coefficients were similar to those obtained for a variety of macrobenthic organisms in controlled laboratories and field studies.  相似文献   
527.
随着城镇污水处理厂规模的快速发展,污水处理伴生的生活污泥产量越来越多,而传统的污泥处置方法具有较大的局限性,困扰着污水处理行业的进一步发展。通过分析目前污泥堆肥存在的问题,探索通过筛选能够强烈分解有机物料的多种好氧、厌氧及兼性菌株复合制成污泥兼氧发酵复合菌剂,开发出适于污泥兼氧发酵的模式;阐述了兼氧发酵复合菌作用过程的原理,并以试验加以验证了该模式用于污泥处置的可行性与实用性。  相似文献   
528.
• Polystyrene microplastic caused hormesis-like effects in Phaeodactylum tricornutum. • Low concentration of microplastic promoted growth, otherwise the opposite was true. • The change trends of pigment contents were opposite at two initial algae densities. • The chlorophyll fluorescence parameters were more sensitive at low algae density. The effects of pristine polystyrene microplastics (pMPs) without any pretreatment at different concentrations (0, 10, 20, 50, and 100 mg/L) on Phaeodactylum tricornutum Bohlin at two initial algae densities (105 and 106 cells/mL) were assessed in this study. Hormesis-like effects were found when microalgae grew with pMPs. The results showed that pMPs inhibited microalgae growth under a high concentration of microplastics tolerated by individual algal cell (low initial algae density) (up to −80.18±9.71%) but promoted growth when the situation was opposite (up to 15.27±3.66%). The contents of photosynthetic pigments including chlorophyll a, chlorophyll c and carotenoids showed resistance to pMPs stress under a low initial algae density and increased with time, but the opposite was true under a high initial algae density. Compared with the low initial algae density group, Qp received less inhibition, and NPQ (heat dissipation) also decreased under the high initial algae density. Under the low initial algae density, OJIP parameters such as Sm, N, Area, Pi Abs, ѱo, φEo, TRo/RC and ETo/RC were more perturbed initially and returned to the levels of the control group (without pMPs) over time, but they remained stable throughout the experiment at high initial algae density. These results show that microplastics in the marine environment may have different toxic effects on P. tricornutum at different growth stages, which is of great significance for understanding the impact of microplastics on marine microalgae and aquatic ecosystems.  相似文献   
529.
Cheng CY  Liu LL  Ding WH 《Chemosphere》2006,65(11):2152-2159
The occurrence and distribution of alkylphenols (APs, i.e., 4-tert-octylphenol (4-t-OP) and 4-nonlyphenol isomers (4-NP)) in oysters (Crassostrea gigas), snails (Thais clavigera), coastal water and coastal sediments of the western coast of southern Taiwan are investigated. Alkylphenols were present in all matrices of interest: in water, ranging from 61 to 370 ng/l, in sediments, ranging from 27 to 190 ng/g, and in biota samples (i.e., oyster and snail), ranging from 20 to 5190 ng/g. Statistical analysis indicated that the probability distribution of most determined concentrations in oyster and snail samples was log-normal distribution. The bioaccumulation of APs resulted in a seasonal variation with respect to their compositions and concentrations in oyster and snail samples. For oysters, concentrations of APs in winter exceeded those in summer. In contrast, those in snails in summer exceeded those in winter. Estimated biomagnification factors of APs from snails to oysters ranged from 1.4 to 4.3 in summer, and 0.5 to 0.8 in winter on the dry weight basis. The results suggested that seasonally mediated physiological changes, such as dilution caused by growth, biotransformation and metabolism, may affect the bioaccumulation of APs in according to season and organism.  相似文献   
530.
Beck IC  Bruhn R  Gandrass J 《Chemosphere》2006,63(11):1870-1878
In the present study, the yeast estrogen screen (YES) has been used to assess the estrogenic activity in surface waters of a coastal region in the German Baltic Sea. Solid-phase extraction using the copolymer Oasis HLB followed by a clean-up on silica was carried out on approximately 50-l water samples. From the final 400 μl extract volume, 100 μl aliquots were used for the measurement of estrogenic activity and for chemical analysis, which was performed by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS). From 29 samples taken during two campaigns (2003 and 2004) at five different stations 27 samples showed an estrogenic response higher than 10%. The response in the YES was expressed as measured estradiol equivalents (EEQs), which were in the range of 0.01 (Darss Peninsula) to 0.82 ng/l (Inner Wismar Bay). Samples from stations located in inner coastal waters showed higher estrogenic activities than those from outer located stations. A comparison of measured estrogenicity (YES) and calculated estrogenicity (chemical analysis) showed significant differences, probably due to the presence of anti-estrogenic compounds and/or the estrogenic activity of unknown, not identified contaminants. The main contributors to the overall estrogenic activity were synthetic and natural hormones.  相似文献   
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