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931.
柠檬酸清洁生产工艺的研究 总被引:8,自引:0,他引:8
分析了传统檬酸生产工艺存在的污染问题,提出了在柠檬酸生产过程中采用清洁生产技术的各种途径。 相似文献
932.
钛白废酸固液分离与综合利用 总被引:2,自引:0,他引:2
介绍了湖南株洲化工集团有限责任公司钛白废酸固液分离与综合利用工艺。将钛白废酸固液分离后得到的清废酸用作磷肥生产用硫酸稀释液、钛白酸解工序硫酸稀释液和板框浸取液,取得了较好的经济效益和环境效益。 相似文献
933.
柠檬酸生产废水处理技术 总被引:8,自引:0,他引:8
分析了柠檬酸生产废水的来源及水质特性,综述了厌氧生物法、厌氧-好氧生物组合法、乳状液膜法等在柠檬酸废水处理中的应用,介绍了中和废水回用和利用柠檬酸发酵废液开发糖化酶制剂的技术。 相似文献
934.
935.
Richard Gattin Alain Copinet Celine Bertrand Yves Couturier 《Journal of Polymers and the Environment》2001,9(1):11-17
The degradation of starch- and polylactic acid-based plastic films by microorganisms extracted from compost was studied in a liquid medium. The various degradation products produced were measured throughout the duration of the experiment, and total carbon balances were estimated. For an easily biodegradable material, the evolution of the way carbon repartitioned between different degradation products was quite similar whatever the experimental condition or the type of substrate. On the other hand, for a resistant material exposed to these microorganisms, the nature of the biodegradation depended strongly on the experimental conditions. In the latter case, a differential scanning calorimetry analysis confirmed the importance of the applied norm on the state of the residual material. The consequences for improved methods of estimation of biodegradability of these materials are discussed. 相似文献
936.
Ahmed E. Bishara Habib I. Shaban Hamad Al-Adwani Sami H. Ali 《Journal of Polymers and the Environment》2001,9(4):137-147
A novel copolymer system has been synthesized using methyl hydroquinone diacetate (MHQDA), 1,4 naphthalene dicarboxylic acid (1,4 NDCA), and polybutylene terephthalate (PBT) using the melt polymerization technique. The optimum kinetic parameters pertinent to this system are reported in this study. A simple second-order reaction sequence summarizes catalyzed and uncatalyzed reactions between MHQDA, 1,4 NDCA, and PBT. The kinetic parameters for the copolymerization reaction were determined using a new second-order model. This technique was used to compute the moles of acetic acid generated in the polymerization process. The model was compared to that of the experimentally determined data. Close comparison (percentage error of less than 5%) was obtained between the experimental and theoretical data. The kinetic data support block copolyester formation. The thermal data also supports formation of block polymers. 相似文献
937.
A Literature Review of Poly(Lactic Acid) 总被引:32,自引:0,他引:32
Donald Garlotta 《Journal of Polymers and the Environment》2001,9(2):63-84
A literature review is presented regarding the synthesis, and physicochemical, chemical, and mechanical properties of poly(lactic acid)(PLA). Poly(lactic acid) exists as a polymeric helix, with an orthorhombic unit cell. The tensile properties of PLA can vary widely, depending on whether or not it is annealed or oriented or what its degree of crystallinity is. Also discussed are the effects of processing on PLA. Crystallization and crystallization kinetics of PLA are also investigated. Solution and melt rheology of PLA is also discussed. Four different power-law equations and 14 different Mark–Houwink equations are presented for PLA. Nuclear magnetic resonance, UV–VIS, and FTIR spectroscopy of PLA are briefly discussed. Finally, research conducted on starch–PLA composites is introduced. 相似文献
938.
Reduction of sulphur deposition causesrecovery of acidified surface waters. Processes in thecatchment delay recovery. The acidification model MAGICwas applied to the Vikedal and Tovdal rivers in southernNorway. Response in water chemsitry is delayed by 10–20 yr. The delay is due to release of old sulphate atVikedal and cation exchange at Tovdal. Assuming that theGothenburg protocol is fully implemented by the year2010, much of the predicted increase of ANC will occur inthe next 10 yr with a levelling off by about 2040. Ifnitrogen leaching increases in the future, however,recovery of ANC will not be as rapid, nor as complete.Critical load for acidity calculated by steady-statemodels is confirmed by the MAGIC predictions. Futurerequirement for mitigation measures such as liming willdecrease in the future as acid deposition decreases. Bythe year 2046 the liming requirement will be reduced byabout 45% at Vikedal and 65% at Tovdal. One of the mainpurposes of the Norwegian national monitoring programmeis to provide documentation of changes in environmentalquality due to long-range transported air pollutants.Modelling applications such as this clearly show that thedata fill this purpose. 相似文献
939.
Waste plastics recycling by an entrained-flow gasifier 总被引:1,自引:0,他引:1
Takatoshi Shoji Kenjiro Shindoh Hironori Ozaki Atsushi Sodeyama 《Journal of Material Cycles and Waste Management》2001,3(2):75-81
We studied an entrained-flow gasification process which efficiently converts waste plastics to energy at a high energy recovery
rate. Waste plastics, after being shredded to <8 mm or <14 mm, were fed into an entrained-flow gasifier with air and oxygen.
In the gasifier, organic substances were pyrolyzed, partially combusted, and then converted into synthetic gas (CO, H2) at a high temperature (over 1600 K). The clarified gasification characteristics were that the lower heat value (LHV) of
the product gas was over 4.2 MJ/Nm3 and the cold gas efficiency was approximately 60%. Other inert substances in the wastes such as ashes and metals were melted
into slag and condensed on bag filters. The bag filters and a water scrubber removed impurities such as dusts, heavy metals,
and hydrogen halides from the product gases. Solid hydrocarbons, which include char and soot, were removed at a hot cyclone
and on the bag filters.
Received: July 19, 2000 / Accepted: October 3, 2000 相似文献
940.