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91.
建立了一种简单方便的纤维素改性的固相合成方法。采用普遍廉价的滤纸作为原料,用固相合成法将预处理后的滤纸纤维经琥珀酸酐进行酯化改性,制备成新型的纤维素吸附剂,通过质量增比、扫描电镜、傅里叶红外光谱仪和X射线衍射仪对制备的吸附剂进行了分析表征,并且探究了离子初始浓度、溶液p H和吸附时间对改性纤维素吸附铜离子的影响。结果表明,在室温下初始离子浓度为1 000 mg/L,离子溶液体积为50 m L,加入0.1 g纤维改性剂,p H为4.0~5.0,吸附平衡时间为50 min时,滤纸纤维改性后最大吸附铜离子质量可达470 mg/g,铜离子去除率达到94%。 相似文献
92.
Junyi Hu Yu Shen Song Pang Yun Gao Guoyong Xiao Shujun Li Yingqian Xu 《环境科学学报(英文版)》2013,(S1):S32-S35
The decay of wood and other cellulosic materials by fungi cause significant economic loss. The widely used chromated copper arsenate was prohibited for the environmental impact and safety of arsenic and chromium. It was found that natural product hinokitiol (HK) had fungicidal and insecticidal activities, and its toxicity was bearable for the environment. We described the practical synthesis of HK-K salt. According to the GB/T18261-2000 and LY/T1283-1998, wood preservative performance of HK-K salt was tested. The results showed that the best inhibitory concentration of HK-K salt was 50 mg/L, for which the prevention effectiveness on mold is better, the killed value is between 0 and 1, and the corrosion-resistant for wood-rotting fungi is grade A. 相似文献
93.
基于多目标决策的节能减排绩效评估 总被引:4,自引:1,他引:3
利用全排列多边形图示指标法构建评价模型,从资源能源消耗、污染物排放、综合利用、环保治理及无害化等方面构建节能减排评价指标体系,并对福建省2001-2010年节能减排进行绩效评估.结果表明,福建省节能减排绩效的优劣顺序分别为:2010、2009、2003、2002、2008、2007、2004、2001、2006、2005年.2005-2006年福建省在废物综合利用、环保治理及无害化等方面取得了一定的成效,但与2001-2004年相比优势不明显,而在资源能源消耗与污染排放方面却出现了大幅度的下滑.2007年以来,福建省正在逐步加大重点行业和重点企业的节能减排力度,因此,在节能减排方面取得了较明显的成效.评价结果较好地体现了福建省节能减排的现状与不足,为推动节能减排绩效评估工作的发展提供了科学依据. 相似文献
94.
水中的溴离子(Br-)和溴酸根离子(BrO3-)由于难挥发、易溶解、稳定性好而难以除去,因此,制备了一种对较低浓度的Br-和BrO3-都有良好吸附去除效果的季铵碱树脂(Quaternary ammonium base resin,QABR)并表征了其物化结构.同时,考察了初始浓度、QABR投加量、溶液pH、离子强度、吸附接触时间和吸附温度等因素对QABR吸附Br-和BrO3-性能的影响.结果表明,在0.05~4.00 mmol·L-1浓度范围内,在298 K、pH=7.0时QABR对Br-和BrO3-的吸附能力最佳,其最大吸附量分别为1.78 mmol·g-1和1.65 mmol·g-1;QABR对Br-和BrO3 相似文献
95.
Organosilicas with chemically immobilized 3-aminopropyl and Methyl Red-containing surface groups were prepared by sol-gel condensation of tetraethyl orthosilicate and (3-aminopropyl)triethoxysilane in the presence of dye as part of the mixed micelles or dye-containing silane as silica source. The hexagonally arranged mesoporous structure of synthesized materials was confirmed by low-temperature nitrogen adsorption-desorption, x-ray diffraction, and TEM studies. Chemical composition of MCM-41-type organosilicas was established by FT-IR spectroscopy and chemical analysis of surface layer. Sorption of Methyl Red by organosilicas was studied from diluted phosphate buffer solutions in dependence of medium pH, duration of contact, and equilibrium concentration of dye. It was found that effective removal of Methyl Red takes place at pH values within a range of 2.5?5. Kinetic curves of Methyl Red sorption on organosilicas were analyzed by the Lagergren, Ho-McKey, and Weber-Morris kinetic models. It was found that the pseudo-second-order model fits the kinetics of Methyl Red sorption on all synthesized materials and the intraparticle diffusion is not the only one mechanism controlling the rate of Methyl Red sorptive removal. The parameters of equilibrium sorption of Methyl Red on organosilicas of MCM-41 type were calculated using Langmuir, Freundlich, Redlich-Peterson, and Brunauer-Emmett-Teller models. Sorption of acid dyes with geometry similar or substantially different from Methyl Red on mesoporous silicas was studied from single and binary component mixtures in aqueous solutions with pH 4.8 and 5.5. It was found that selective sorption process is highly dependent on the structural characteristics and protolytic state of silica surface as well as acid dye. 相似文献
96.
针对污水中磷的去除问题,采用优化后的恒定pH值共沉淀法制备了Mg/Al-layered double hydroxides(Mg/Al-LDHs),经高温焙烧得到高效磷吸附剂Mg/Al-layered double oxide(Mg/Al-LDO);在对其吸附特性研究的基础上,并结合Zeta电位、XRD、FTIR分析吸附前后材料等电点、晶体结构及层间阴离子的变化,探讨Mg/Al-LDO吸附除磷机制.结果表明,采用优化后的共沉淀法,在Mg/Al比为2∶1,焙烧温度450℃,焙烧时间2 h条件下制备出的Mg/Al-LDO对磷酸根吸附性最好,最大吸附容量可达到176.94 mg·g-1,与理论吸附容量191.57 mg·g-1基本一致,远高出Mg/Al-LDHs及其它磷吸附剂.实验数据对准二级反应动力学模型的拟合结果较好,吸附过程符合Langmuir吸附等温模型.结合Zeta电位、XRD、FTIR的结果推测,Mg/AlLDO吸附除磷主要是通过静电引力、阴离子插层、离子交换、表面配位这4种作用协同完成. 相似文献
97.
为了获得适用于海水中有机污染物光降解催化剂,分别选用纳米SiO_2粒子和氧化石墨烯GO为载体,利用吸附相反应技术并结合热处理过程制备了基于TiO_2的复合催化剂,研究了弱光(光强小于1mW·cm~(-3))激发下复合催化剂光催化降解模拟海水中苯酚.结果表明,吸附相反应技术结合焙烧得到的La~(3+)掺杂TiO_2-SiO_2,表面亲水性较强和对苯酚吸附能力较弱,难以克服盐离子的干扰并有效降解模拟海水中高浓度苯酚.而吸附相反应技术结合醇溶剂热还原处理后,La~(3+)掺杂TiO_2-SiO_2催化剂表面亲水性显著减弱,但该催化剂在模拟海水中不能形成稳定的悬浮体系.吸附相反应技术得到的TiO_2-GO和La~(3+)掺杂TiO_2-GO中,TiO_2粒子粒径小于10nm且均匀负载于GO的表面.醇溶剂热还原处理可使TiO_2形成晶型结构,从而提高其催化活性,同时还能将GO表面的含氧基团还原,降低催化剂表面亲水性.从而提升催化剂对苯酚的吸附能力和对盐离子的抗干扰能力.另外,还原GO与小粒径TiO_2粒子紧密结合,使光生电子能很快转移至还原GO表面,增大光生电荷分离率,进一步提升催化剂的光降解性能. 相似文献
98.
One of the key advantages of meta‐analysis (i.e., a quantitative literature review) over a narrative literature review is that it allows for formal tests of interaction effects—namely, whether the relationship between two variables is contingent upon the value of another (moderator) variable. Interaction effects play a central role in organizational science research because they highlight boundary conditions of a theory: Conditions under which relationships change in strength and/or direction. This article describes procedures for estimating interaction effects using meta‐analysis, distills the technical literature for a general readership of organizational science researchers, and includes specific best‐practice recommendations regarding actions researchers can take before and after data collection to improve the accuracy of substantive conclusions regarding interaction effects investigated meta‐analytically. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
99.
Martin J. Steinbauer Fredrik Östrand Tom E. Bellas Anna Nilson Fredrik Andersson Erik Hedenström Michael J. Lacey P. Florian Schiestl 《Chemoecology》2004,14(3-4):217-223
Summary. The autumn gum moth, Mnesampela privata
(Guenée) (Lepidoptera: Geometridae), is native to Australia
and can be a pest of plantation eucalypts. Field-collected
and laboratory-reared female autumn gum moths were
dissected to remove glands likely to contain components of
the sex pheromone. Using gas chromatography (GC) and
combined gas chromatography–mass spectrometry (GC-MS),
three compounds were identified from female extracts,
namely (3Z,6
Z,9
Z)-3,6,9-nonadecatriene, 1-hexadecanol
and 1-octadecanol (confirmed by comparison with synthetic
samples). Nonadecatriene elicited an antennal response in
male autumn gum moth during gas chromatographic
analyses combined with electroantennographic detection
(GC-EAD). In electroantennogram (EAG) recording male
M. privata antennae responded to the nonadecatriene. Nonadecatriene was synthesised via Kolbe electrolysis,
starting with (9Z,12Z,15Z)-octadeca-9,12,15-trienoic acid
(linolenic acid) and propanoic acid or via an alternative
four-step method also starting from linolenic acid. In field
trials (3Z,6Z,9Z)-3,6,9-nonadecatriene proved attractive
to male moths. Thus, we conclude that (3Z,6Z,9Z)-3,6,9-
nonadecatriene is a sex pheromone component of autumn
gum moth. This component has been identified in extracts
from other geometrids in the same subfamily, Ennominae.
However, to our knowledge this is the first example where
(3Z,6Z,9Z)-3,6,9-nonadecatriene has been found in females
and also proved attractive to male moths when presented on its
own. Our results are discussed in relation to other geometrid
pheromones. 相似文献
100.