全文获取类型
收费全文 | 469篇 |
免费 | 12篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 39篇 |
废物处理 | 30篇 |
环保管理 | 72篇 |
综合类 | 84篇 |
基础理论 | 83篇 |
污染及防治 | 118篇 |
评价与监测 | 29篇 |
社会与环境 | 28篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 11篇 |
2017年 | 12篇 |
2016年 | 15篇 |
2015年 | 9篇 |
2014年 | 21篇 |
2013年 | 51篇 |
2012年 | 14篇 |
2011年 | 35篇 |
2010年 | 17篇 |
2009年 | 22篇 |
2008年 | 25篇 |
2007年 | 29篇 |
2006年 | 28篇 |
2005年 | 19篇 |
2004年 | 19篇 |
2003年 | 25篇 |
2002年 | 16篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1973年 | 1篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1961年 | 2篇 |
1957年 | 1篇 |
1956年 | 2篇 |
1955年 | 3篇 |
1949年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有490条查询结果,搜索用时 10 毫秒
21.
Dr. Waldo Sepulveda Peter Nicolaidis Jean Hollingsworth Nicholas M. Fisk 《黑龙江环境通报》1995,15(2):193-197
The fetal gall bladder can now be easily identified during the second and third trimesters using high-resolution ultrasonography. In this report we present eight fetuses with an enlarged gall bladder detected on prenatal ultrasonography at a mean gestational age of 24.6 weeks (range 19–31 weeks). Additional ultrasonographic findings were present in four cases: fetal anomalies and intrauterine growth retardation in three and polyhydramnios in one. Of those cases associated with fetal anomalies, one woman underwent amniocentesis at 21 weeks revealing trisomy 18. The other two declined prenatal karyotyping; neonatal karyotyping revealed trisomy 13 in one and trisomy 18 in the other. Although an enlarged fetal gall bladder can be a normal variant in the second and third trimesters, the prenatal detection of cholecystomegaly should prompt a search for associated anomalies and other markers of aneuploidy. If found, prenatal karyotyping should be considered. 相似文献
22.
Dos Santos HH Demarchi CA Rodrigues CA Greneche JM Nedelko N Slawska-Waniewska A 《Chemosphere》2011,82(2):278-283
It was reported the adsorption of As(III) on the surface of the chitosan-Fe-crosslinked complex. Theoretical correlation of the experimental equilibrium adsorption data for As(III)/Ch-Fe system is best explained by the non-linearized form Langmuir-Freundlich isotherm model. At optimum conditions, pH 9.0, the maximum adsorption capacity, calculated using the Langmuir-Freundlich isotherm model was 13.4 mg g−1. The adsorption kinetics of As(III) onto Ch-Fe are described by the pseudo-first-order kinetic equation. The results of the Mössbauer spectroscopy showed that there is no redox process on the surface of the adsorbent. 相似文献
23.
Maria das Graças Alonso de Oliveira Jean Nunes dos Santos Patrícia Ramos Cury Victor Hugo Pereira da Silva Nara Rejane Cruz Oliveira Ricardo da Costa Padovani Adriana Marcassa Tucci Daniel Araki Ribeiro 《Environmental science and pollution research international》2014,21(8):5760-5764
The aim of the present study was to comparatively evaluate genomic damage (micronucleus) and cellular death (pyknosis, karyolysis, and karyorrhexis) in exfoliated oral mucosa cells from crack cocaine users by micronucleus test. A total of 30 crack cocaine users and 30 health controls (non-exposed individuals) were included in this setting. Individuals had epithelial cells from cheek mechanically exfoliated, placed in fixative, and dropped in clean slides, which were checked for the above nuclear phenotypes. The results pointed out significant statistical differences (p?<?0.05) of micronucleated oral mucosa cells from crack cocaine users. Exposure to crack cocaine caused an increase of other nuclear alterations closely related to cytotoxicity such as karyolysis in oral cells as well. In summary, these data indicate that crack cocaine is able to induce chromosomal breakage and cellular death in oral mucosa cells of users. 相似文献
24.
Jean P. Paré M.Sc 《Journal of the Air & Waste Management Association (1995)》2013,63(6):325-327
The lead acetate paper tape reagent method for the estimation of hydrogen sulfide in air has been reviewed with the conclusions that the colored spots on which the quantitative estimation is based are not stable and do not lend by themselves to accurate results. Although it may be retained for grab sampling work, the lead acetate paper tape reagent is not acceptable as a stoichiometric reagent in any case where long duration sampling periods are concerned like in air pollution studies. A new mercuric chloride paper tape reagent has been developed as a substitute. Due to the fact that the colored spots resulting from the action of hydrogen sulfide on mercuric chloride are sensitive and very stablet, this new paper tape reagent is proposed as an adequate and reliable analytical too for the estimation of hydrogen sulfide in air. Also, a more comprehensive application of the paper tape analytical system is proposed throughout a suitable control of the factor tape retention capacity vs sampling rate which imposes some restrictions in the selection of the practical working range of concentrations. Nevertheless this working range is still wide enough to encompass all the hydrogen sulfide concentrations normally encountered in the city atmosphere. 相似文献
25.
Franco Andreone Gonçalo M. Rosa Jean Noël Angelica Crottini Miguel Vences Christopher J. Raxworthy 《Die Naturwissenschaften》2010,97(6):525-543
We describe a new mantelline frog of the genus Blommersia found in rainforest in North East Madagascar, from the protected areas of Ambatovaky, Betampona, Masoala, and Zahamena. Blommersia angolafa n.sp. is a small frog, with a body size of 17–21 mm, expanded finger and toe tips, and colouration ranging from yellow to
dark brown, with pale-bluish spots on the flanks and light tips of fingers and toes. A peculiar aspect characterising this
new species is its novel life history and reproductive mode. Both sexes live and breed in a phytotelmic habitat of water accumulated
within fallen prophylls and fallen leaf sheaths of at least three species of Dypsis palms. Within these phytotelmata, egg laying and complete larval development occur. Thus, B. angolafa n.sp. represents a new evolutionary lineage of Malagasy frogs in which phytotelmy is known. Up to now, reproduction in phytotelmata
in Malagasy frogs has been reported for many cophyline microhylids, most species of Guibemantis, Mantella laevigata, and possibly in a still-undescribed species belonging to the genus Spinomantis. We consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of
lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding
strategy. The new species, being specialised to a habitat represented by a few selected Dypsis species, potentially suffers the selective exploitation of these palms. 相似文献
26.
Special needs hurricane shelters and the ageing population: development of a methodology and a case study application 下载免费PDF全文
Mark W. Horner Eren Erman Ozguven Jean Michael Marcelin Ayberk Kocatepe 《Disasters》2018,42(1):169-186
Recent experience of hurricanes, particularly in the southeast United States, has heightened awareness of the multifaceted nature of and the challenges to effective disaster relief planning. One key element of this planning is providing adequate shelter at secure locations for people who evacuate. Some of these individuals will have ‘special needs’, yet there is little research on the relationship with shelter space. This study designed a geographic information systems‐based network optimisation methodology for the siting of special needs hurricane relief shelters, with a focus on the transportation component. It sought to find new locations for shelters that maximise accessibility by vulnerable populations, given capacity constraints, concentrating on the ageing population. The framework was implemented in a medium‐sized metropolitan statistical area in the state of Florida where data suggest a possible deficit in special needs shelter space. The study analysed options for increasing special needs shelter capacity, while considering potential uncertainties in transportation network availability. 相似文献
27.
中国环境镉接触人群低骨密度及肾功能不全的研究 总被引:19,自引:0,他引:19
25年前,Ambio曾载文提出应警惕环境镉污染引起的健康效应.1998年在中国进行了这方面的研究,评价了因食用大米而接触镉人群的前臂骨密度(BMD)和肾功能,发现尿镉(CdU)或血镉(CdB)高的绝经后妇女及血镉(CdB)高的男性,BMD均有所下降.在CdB或CdU与肾功能不全(视黄醇结合蛋白排泄增加)之间也发现了明显的、有统计学意义的剂量-效应关系及剂量-反应关系.第一次报道了日本以外的亚洲地区镉接触人群中存在骨不良效应.本文的意义在于阐明了亚洲的环境镉接触人群中仍存在着与肾和骨(镉的比较严重的有害效应)的联合效应,也讨论了一些欧洲镉接触人群的骨效应. 相似文献
28.
29.
30.