全文获取类型
收费全文 | 489篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 5篇 |
环保管理 | 14篇 |
综合类 | 252篇 |
基础理论 | 80篇 |
污染及防治 | 113篇 |
评价与监测 | 14篇 |
社会与环境 | 12篇 |
出版年
2018年 | 5篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 9篇 |
2013年 | 18篇 |
2012年 | 11篇 |
2011年 | 9篇 |
2010年 | 12篇 |
2009年 | 23篇 |
2008年 | 15篇 |
2007年 | 30篇 |
2006年 | 12篇 |
2005年 | 8篇 |
2004年 | 9篇 |
2003年 | 13篇 |
2002年 | 16篇 |
2001年 | 15篇 |
2000年 | 6篇 |
1999年 | 9篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1987年 | 4篇 |
1981年 | 4篇 |
1967年 | 6篇 |
1966年 | 4篇 |
1965年 | 5篇 |
1964年 | 8篇 |
1963年 | 15篇 |
1962年 | 4篇 |
1961年 | 7篇 |
1960年 | 5篇 |
1959年 | 6篇 |
1958年 | 10篇 |
1957年 | 10篇 |
1956年 | 9篇 |
1955年 | 13篇 |
1954年 | 6篇 |
1952年 | 4篇 |
1951年 | 3篇 |
1950年 | 6篇 |
1947年 | 5篇 |
1943年 | 6篇 |
1940年 | 3篇 |
1939年 | 4篇 |
1924年 | 3篇 |
排序方式: 共有493条查询结果,搜索用时 31 毫秒
101.
Gerhard Blickle James A. Meurs Andreas Wihler Christian Ewen Andrea Plies Susann Günther 《组织行为杂志》2013,34(8):1145-1164
Caveats concerning the ability of personality to predict job performance have been raised because of seemingly modest criterion‐related validity. The goal of the present research was to test whether narrowing the context via the type of job (i.e., jobs with complex task demands) and adding a social skill‐related moderator (i.e., political skill) would improve performance prediction. Further, along with political skill, the broad factor of personality demonstrated in prior research to have the strongest criterion validity (i.e., conscientiousness) was joined with a narrow construct closely related to openness to experience (i.e., learning approach) in a three‐way interactive prediction of supervisor‐rated task performance. With the employee–supervisor dyads among professionals, but not with the control group of non‐professional employees, task performance was predicted by the three‐way interaction, such that those high on all three received the highest performance ratings. Implications, strengths and limitations, and directions for future research are discussed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
102.
Ummat Somjee Kelly Ablard Bernard Crespi Paul W. Schaefer Gerhard Gries 《Behavioral ecology and sociobiology》2011,65(5):1071-1077
Local mate competition (LMC) occurs when brothers compete with each other for mating opportunities, resulting in selection
for a female-biased sex ratio within local groups. If multiple females oviposit in the same patch, their sons compete for
mating opportunities with non-brothers. Females, in the presence of other females, should thus produce relatively more sons.
Sex ratio theory also predicts a more female-biased sex ratio when ovipositing females are genetically related, and sex-ratio
responses to foundress size if it differentially affects fitness gains from sons versus daughters. The mating system of the
parasitoid wasp Ooencyrtus kuvanae meets assumptions of LMC. Females insert a single egg into each accessible egg of gypsy moth, Lymantria dispar, host egg masses. Wasps complete development inside host eggs and emerge en masse, as sexually mature adults, resulting in
intense competition among brothers. We tested the hypothesis that O. kuvanae exhibits LMC by manipulating the number of wasp foundresses on egg masses with identical numbers of eggs. As predicted by
LMC theory, with increasing numbers of wasp foundresses on an egg mass, the proportions of emerging sons increased. In contrast,
the presence of a sibling compared to a non-sibling female during oviposition, or the size of a female, did not affect the
number or sex ratio of offspring produced. The O. kuvanae system differs from others in that larvae do not compete for local resources and thus do not distort the sex ratio in favor
of sons. With no resource competition among O. kuvanae larvae, the sex ratio of emergent son and daughter wasps is due entirely to the sex allocation by ovipositing wasp foundresses
on host egg masses. 相似文献
103.
Asexual propagation is an underappreciated way of increasing the sessile population of the metagenetic Scyphozoa. Our studies
on Sanderia malayensis have shown a great variety of asexual reproduction modes. A new mode of polyp asexual propagation is described. By integrating
earlier reported modes occurring in other species we established a classification which may serve as a standard tool to describe
asexual propagation in Scyphozoa.
The experiments performed comply with the current laws of Germany. 相似文献
104.
Peter E. Schmid und Jenny M. Schmid-Araya 《Umweltwissenschaften und Schadstoff-Forschung》2001,13(5):255-257
Ohne Zusammenfassung 相似文献
105.
106.
107.
Different 2,3,7,8-substituted polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs) were investigated for their retention behaviour on a disposable minicolumn containing activated carbon AX-21. Elution behaviour and recovery were examined, using native and radiolabelled PCDD and PCDF isomers.
A comparison of the total mass chromatograms of PCDDs and PCDFs in an extract from animal adipose tissue, before and after activated carbon treatment, demonstrates the efficiency of this cleanup step with respect to the elimination of interfering compounds. 相似文献
108.
In the Federal Republic of Germany, benzene is one of the most important basic materials for the chemical industry. Only a relatively small proportion of the pure benzene processed in the chemical industry is emitted into the environment (ca. 40t in 1991). But the substance is also a natural component of the crude oil in gasoline and is released during incomplete combustion or is formed out of other aromatic substances. The primary source of emissions, with more than 10,000 t/yr (approximately 85% of this from motor vehicles with Otto engines), is commercial motor vehicle transportation. Benzene concentrations in the environment are approximately <1 μg/m3 in rural areas, 20–30 μg/m3 near main roads (peak levels in highly urbanized regions with much traffic as high as approximately 100 μg/m3) and 7–15 μg/m3 in the vicinity of industrial polluters. It has not been possible to detect a specific trend over time during the last ten years. An increased exposure (approx. 350–27,000 μg/m3) is likely while filling the tank and within the motor vehicle (approx. 10–200 μg/m3) due to gasoline volatilization from pipes, etc. Compared to outdoor air, higher concentrations of benzene (approx, 2–11 μg/m3) are measured in the indoor air which contains additionally benzene from tobacco smoke, equipment, renovating work and heating. The primary exposure pathway of benzene in humans is inhalation. Apart from individuals with occupational exposure, smokers have the highest internal benzene burden. Measures undertaken during recent years to reduce the amount of emissions have been counteracted at least in part by the increase in motor vehicle traffic. Further measures to reduce the emissions or to change the transporttation policies must still be or have already been initiated. 相似文献
109.
Polycyclic aromatic hydrocarbons in Norwegian forest soils: impact of long range atmospheric transport 总被引:8,自引:0,他引:8
Levels of nine selected polycyclic aromatic hydrocarbons, PAHs, in surface soils from areas in southern and central Norway are presented. Levels in central Norway are generally low, while the southern Norway soils are about ten-fold higher with respect to 4 and 5 ring PAHs. Comparison with air quality data indicates long-range atmospheric transport to be the major source of the excess 4 and 5 ring PAHs in the south. Analyses of peat cores from ombrotrophic bogs support this assumption, and these provide a potentially useful approach for temporal studies of atmospheric PAH deposition. Analytical data for naphthalene in soils depend very much on the sampling and storage of the samples before analysis. 相似文献
110.