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191.
本文按照反应类型综述了原子光谱法间接测定水中非金属和阴离子,特别对饮用水和人发中砷及水和废水中Cl^-1的分析方法进行了讨论,指出了间接法的发展方向。 相似文献
192.
流变相法制备包覆型CMC-Fe0及降解水中TCE的研究 总被引:1,自引:0,他引:1
以廉价环保的羧甲基纤维素钠(CMC)为表面修饰剂,采用流变相反应法制备包覆型纳米零价铁(CMC-Fe0),用XRD、SEM和TEM、氮气吸附-脱附手段对样品进行表征,并利用合成的零价铁粒子对三氯乙烯(TCE)进行还原脱氯反应.结果表明,当CMC-Fe0投加量为6 g·L-1,TCE初始浓度为5 mg·L-1时,反应40 h去除率达100%.包覆型CMC-Fe0对TCE的还原反应符合准一级反应动力学.最后,对反应产物进行了简单易行的回收. 相似文献
193.
Uncertain future payoffs and irreversible costs characterize investment in climate change adaptation and mitigation. Under these conditions, it is relevant to analyze investment decisions in a real options framework, as this approach takes into account the economic value associated with investment time flexibility. In this paper, we provide an overview of the literature adopting a real option approach to analyze investment in climate change adaptation and mitigation, and examine how the uncertain impacts of climate change on the condition of the human environment, risk preferences, and strategic interactions among decisions-makers have been modeled. We found that the complex nature of uncertainties associated with climate change is typically only partially taken into account and that the analysis is usually limited to decisions taken by individual risk neutral profit maximizers. Our findings call for further research to fill the identified gaps.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01342-8) contains supplementary material, which is available to authorized users. 相似文献
194.
Revealing life‐history traits by contrasting genetic estimations with predictions of effective population size
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Gili Greenbaum Sharon Renan Alan R. Templeton Amos Bouskila David Saltz Daniel I. Rubenstein Shirli Bar‐David 《Conservation biology》2018,32(4):817-827
Effective population size, a central concept in conservation biology, is now routinely estimated from genetic surveys and can also be theoretically predicted from demographic, life‐history, and mating‐system data. By evaluating the consistency of theoretical predictions with empirically estimated effective size, insights can be gained regarding life‐history characteristics and the relative impact of different life‐history traits on genetic drift. These insights can be used to design and inform management strategies aimed at increasing effective population size. We demonstrated this approach by addressing the conservation of a reintroduced population of Asiatic wild ass (Equus hemionus). We estimated the variance effective size (Nev) from genetic data (08888892:media:cobi13068:cobi13068-math-0001" class="section_image" src="//wol-prod-cdn.literatumonline.com/cms/attachment/bb7aac07-7e47-4d1e-9dab-bc168060b3f7/cobi13068-math-0001.png">) and formulated predictions for the impacts on Nev of demography, polygyny, female variance in lifetime reproductive success (RS), and heritability of female RS. By contrasting the genetic estimation with theoretical predictions, we found that polygyny was the strongest factor affecting genetic drift because only when accounting for polygyny were predictions consistent with the genetically measured Nev. The comparison of effective‐size estimation and predictions indicated that 10.6% of the males mated per generation when heritability of female RS was unaccounted for (polygyny responsible for 81% decrease in Nev) and 19.5% mated when female RS was accounted for (polygyny responsible for 67% decrease in Nev). Heritability of female RS also affected Nev; 08888892:media:cobi13068:cobi13068-math-0002" class="section_image" src="//wol-prod-cdn.literatumonline.com/cms/attachment/64a8056a-6431-4c41-811a-e1daee8ae870/cobi13068-math-0002.png"> (heritability responsible for 41% decrease in Nev). The low effective size is of concern, and we suggest that management actions focus on factors identified as strongly affecting 08888892:media:cobi13068:cobi13068-math-0003" class="section_image" src="//wol-prod-cdn.literatumonline.com/cms/attachment/c75c2025-564b-44b2-8987-c9a29d7a8d40/cobi13068-math-0003.png">, namely, increasing the availability of artificial water sources to increase number of dominant males contributing to the gene pool. This approach, evaluating life‐history hypotheses in light of their impact on effective population size, and contrasting predictions with genetic measurements, is a general, applicable strategy that can be used to inform conservation practice. 相似文献
195.
196.
Derval dos Santos Rosa Maria Regina Calil Cristina das Graças Fassina Guedes Carlos Eduardo O. Santos 《Journal of Polymers and the Environment》2001,9(3):109-113
The biodegradability of poly-06787454295x15m/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-hydroxybutyrate and poly-06787454295x15m/xxlarge603.gif" alt="epsiv" align="BASELINE" BORDER="0">-caprolactone in soil compostage before and after irradiation of the polymers for 192, 425, and 600 h in a Weather-Ometer was examined. The biodegradability tests were done in soil compostage at pH 7.0, 9.0, and 11.0 to assess the influence of this parameter on degradation. The rate of degradation was directly proportional to the soil alkalinity. Poly-06787454295x15m/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-hydroxybutyrate showed the greatest weight loss and aging in a Weather-Ometer did not significantly increase the biodegradation, except when the polymer was aged for 425 h and buried in soil compostage of pH 11.0. 相似文献
197.
Kousaku?OhkawaEmail author Hakyong?Kim Keunhyung?Lee 《Journal of Polymers and the Environment》2004,12(4):211-218
The biodegradation of electrospun nano-fibers of poly(03.gif" alt="epsiv" align="BASELINE" BORDER="0">-caprolactone) (PCL) was initially investigated with respect to the environmental application of PCL non-woven fabrics, using pure-cultured soil filamentous fungi, Aspergillus oryzae, Penicillium caseicolum, P. citrinum, Mucor sp., Rhizopus sp., Curvularia sp., and Cladosporium sp. Three kinds of non-woven PCL fabrics with different mean fiber diameters (330, 360, and 510 nm) were prepared by changing the viscosities of the pre-spun PCL solutions (150, 210, and 310 cPs, respectively). All of the pure-line soil filamentous fungi tested grew on the two fiber materials. Electron microscopy was used to observe the biodegradation processes revealing remarkable growth of two fungi, Rhizopus sp. and Mucor sp., along with the accompanying collapse of the nano-fiber matrices. In the biochemical oxygen demand (BOD) test, the biodegradation of the 330 nm PCL nano-fibers by Rhizopus sp. and Mucor sp. exceeded 20 and 30% carbon dioxide generation, respectively. The biodegradability of the PCL non-woven fabrics decreased with the mean fiber diameter and the 330 nm PCL nano-fiber that was made from 150 cPs solution (concentration, 7 wt%) exhibited the highest biodegradability. These results might offer some clues for the applications of the PCL non-woven fabrics having the controlled biodegradability in the environmental uses. 相似文献
198.
Joris Mergaert Kurt Ruffieux Christophe Bourban Virginie Storms Wim Wagemans Erich Wintermantel Jean Swings 《Journal of Polymers and the Environment》2000,8(1):17-27
A simple and rapid in vitro test was designed for the assessment of the biodegradation of polyester-based plastics by selected biodegrading bacterial strains. Variovorax paradoxus LMG 16137 was used for the degradation of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Acidovorax avenae subsp. avenae LMG 17238 fo the synthetic-based polyesters poly(0k32/xxlarge949.gif" alt="epsi" align="BASELINE" BORDER="0">-caprolactone) (PCL), poly(butylene succinate-co-butylene adipate), and a starch-PCL blend. Degradation by the bacteria was studied in liquid medium with the plastics (films, granules, and injection-molded test bars) as sole sources of carbon. Degradation was followed through gravimetry, growth of the culture, and tensile testing. The effects of incubation time, inoculum density, aeration, incubation temperature, and pH of the medium on the mass loss were investigated and conditions optimized. The test allowed to obtain reproducible results on the mass loss of plastic samples in less than 3 weeks and yielded excellent partially degraded samples for further analysis. 相似文献
199.
200.
The paper describes the application of a new computer automated tool, developed by us, in the risk analysis of a typical chemical industry engaged in the manufacture of linear alkyl benzene. Using the tool014;a comprehensive software package 0?wchp=dGLbVzW-zSkzS" alt="Image" title="Image" style="vertical-align:bottom" border="0" height=11 width="72"/>
-III (MAXimum CREDible accident analysis)014;nine different scenarios, one for each storage unit, have been studied. It is observed that the accident scenario for chlorine (instantaneous release followed by dispersion) leads to the largest area-under-lethal-impact, while the accident scenario for propylene (CVCE followed by fireball) forecasts the most intense damage per unit area. The accidents involving propylene, benzene, and fuel oil have a high possibility of causing domino/secondary accidents as their destructive impacts (shock waves, heat load) would envelope other storage and process units.Besides demonstrating the utilizability of 0?wchp=dGLbVzW-zSkzS" alt="Image" title="Image" style="vertical-align:bottom" border="0" height=11 width="72"/>
-III, this study also focuses attention on the need to bestow greater effort towards risk assessment/crisis management. The authors hope that the study will highlight the severity of the risk posed by the industry and thus generate safety consciousness among plant managers. The study may also help in developing accident-prevention strategies and the installation of damage control devices. 相似文献