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111.
Egress models typically use one of three methods to represent the physical space in which the agents move: coarse network, fine network or continuous. In this work, we present a novel approach to represent space, which we call the ‘Hybrid Spatial Discretisation’ (HSD), in which all three spatial representations can be utilised to represent the physical space of the geometry within a single integrated software tool. The aim of the HSD approach is to encompass the benefits of the three spatial representation methods and maximise computational efficiency while providing an optimal environment to represent the movement and interaction of agents. 相似文献
112.
Although Africa has many threatened species and biological hot spots, there are few citizen science schemes, particularly in rural communities, and there has been limited evaluation of existing programs. We engaged traditional Maasai warriors (pastoralist men aged 15 to 35) in community‐based conservation and demographic monitoring of a persecuted African lion (Panthera leo) population. Through direct engagement, we investigated whether a citizen science approach employing local warriors, who had no formal education, could produce reliable data on the demographics, predation, and movements of a species with which their communities have been in conflict for generations. Warriors were given benefits such as literacy training and skill enhancement and engaged in the monitoring of the lions. The trained warriors reported on lion sign across an area nearly 4000 km2. Scientists worked together with the warriors to verify their reports and gather observations on the lion population. Using the verified reports and collected observations, we examined our scientific knowledge relative to the lion population preceding and during the citizen science program. Our observations showed that data quality and quantity improved with the involvement and training of the participants. Furthermore, because they engaged in conservation and gained personal benefits, the participants came to appreciate a species that was traditionally their foe. We believe engaging other local communities in biodiversity conservation and monitoring may be an effective conservation approach in rural Africa. 相似文献
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114.
Edwin Quarello Fabien Guimiot Jean-Marie Moalic Michel Simoneau Yves Ville Anne-Lise Delezoide 《黑龙江环境通报》2007,27(10):926-931
Objective To investigate the involvement of the genes encoding for COL6A1, COLA2 and super-oxide dismutase (SOD) in the mechanism for the retention of subcutaneous fluid in fetuses with trisomy 21. Methods During a 7-month period (November 2004–May 2005), human fetal skin from the nuchal region was obtained from euploid fetuses and from fetuses with trisomy 21 following abortions and terminations of pregnancy. Cell cultures were performed from nuchal skin. Quantification of COL6A1, COL6A2, COL6A3 and SOD mRNAs were performed using real-time quantitative RT-PCR. Results Twelve fetuses were studied between 13–15 and 19–20 weeks of gestation including 7 cases of trisomy 21. A significant overexpression of genes of interest was demonstrated in trisomy 21 fetuses when compared with euploid fetuses, in the first and in the second trimester of pregnancy (p < 0.0001). Conclusion This study demonstrates a homogeneous overexpression of the genes encoding for α1 and α2 chains of Collagen type VI, and SOD in nuchal skin of human trisomy 21 fetuses. Persistence of this overexpression in the second trimester of pregnancy, despite the absence of an enlarged nuchal translucency (NT), may characterize some compensatory mechanisms. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Martin B. Delatycki Fowzan Alkuraya Alison Archibald Carlo Castellani Martina Cornel Wayne W. Grody Lidewij Henneman Adonis S. Ioannides Edwin Kirk Nigel Laing Anneke Lucassen John Massie Juliette Schuurmans Meow-Keong Thong Irene van Langen Joël Zlotogora 《黑龙江环境通报》2020,40(3):301-310
Reproductive carrier screening started in some countries in the 1970s for hemoglobinopathies and Tay-Sachs disease. Cystic fibrosis carrier screening became possible in the late 1980s and with technical advances, screening of an ever increasing number of genes has become possible. The goal of carrier screening is to inform people about their risk of having children with autosomal recessive and X-linked recessive disorders, to allow for informed decision making about reproductive options. The consequence may be a decrease in the birth prevalence of these conditions, which has occurred in several countries for some conditions. Different programs target different groups (high school, premarital, couples before conception, couples attending fertility clinics, and pregnant women) as does the governance structure (public health initiative and user pays). Ancestry-based offers of screening are being replaced by expanded carrier screening panels with multiple genes that is independent of ancestry. This review describes screening in Australia, Cyprus, Israel, Italy, Malaysia, the Netherlands, Saudi Arabia, the United Kingdom, and the United States. It provides an insight into the enormous variability in how reproductive carrier screening is offered across the globe. This largely relates to geographical variation in carrier frequencies of genetic conditions and local health care, financial, cultural, and religious factors. 相似文献
117.
Carlos Rosas Edwin L. Cooper Cristina Pascual Roberto Brito Rolando Gelabert Teresa Moreno Ariadna Sánchez 《Marine Biology》2007,152(4):929-938
To assess the health status of aquatic ecosystems, specialized tools and strategies are needed to study the changes induced
in oceanic systems by human activity. The Gulf of Mexico has a tremendous ecological importance because of its biological
diversity. The present paper defines baseline levels of blood metabolites and immune components for wild tropical populations
of F. duorarum: an important shrimp species of the Gulf of Mexico. Osmotic pressure (OP), osmotic capability (OC), oxy hemocyanin (OxyHc),
glucose, digestive gland glycogen, proteins, cholesterol, lactate, acylglycerols (AG) were used as indicators of physiological
and nutritional status; phenoloxidase activity, quantification of hemocytes, as well as respiratory burst, were used to assess
the immunological status. There were no differences between sexes in either live weight or physiological and nutritional conditions.
Only total blood protein, oxy hemocyanin, and digestive gland glycogen showed normally distributed data. All the remaining
blood parameters were right- or left-skewed. A median live weight of 9.5 g was registered for the sampled population. Median
values of 955 and −91.85 mOsm/kg (OP and OC, respectively) were obtained, indicating that shrimp were slightly hypo-osmotic
in relation to sea water. A proportion of 27% of OxyHc of the total protein (OxyHc/Prot) was calculated for the F. duorarum population. ProPO and PO showed no normal distribution and were not different between sexes. A right-skewed distribution was
observed. Total hemocytes, hyaline (HC) and granular cells (GC) showed differences between sexes, with higher values in females
than males. A similar proportion of HC (69%) and GC (30%) of total cells were observed between sexes. Basal and activated
respiratory burst showed differences between sexes with higher values for females than for males. The current results provide
indicators of the nutritional and immune status of F. duorarum that can be used to detect changes in trophic relations and health at a population level. 相似文献
118.
The U.S. Environmental Protection Agency (EPA) evaluated an in‐situ application of a soil‐amendment process at a residential site that was contaminated with lead. The goal of the evaluation was to determine if the soil‐amendment process resulted in lower concentrations of bioavailable lead in the contaminated soils. The relative bioavailability of lead (bioaccessible lead) was measured by an in vitro test procedure that uses a highly acidic extraction procedure to simulate human digestive processes. The soil‐amendment demonstration showed that the 11.2 percent mean reduction in bioavailable lead concentration between untreated and treated soils was not statistically different. © 2002 Wiley Periodicals, Inc. 相似文献
119.
Carlos Molinet Edwin Niklitschek Carlos A. Moreno Alejandra Arévalo 《Marine Biology》2008,153(5):779-787
The transport of marine invertebrate larvae is strongly influenced by their distribution in the water column, which could
be affected by the biological features of the larvae and environmental variables. Larvae can modify their swimming behavior
throughout their planktonic cycle, thereby changing the observed distributional patterns. This ability, coupled with oceanographic
features, could induce landward or seaward transport. We studied the vertical distribution of C. concholepas larval stages in two differently stratified systems in Chilean inland seas; Refugio Channel (a strongly stratified channel,
where previously has been described as a frontal system) and Guaitecas (a gently stratified system). Combinations of 12–24 h
larval collection experiments were done simultaneously with fixed temperature and salinity profiles; meteorological data were
also obtained. The results suggest that both salinity and day period influence the C. concholepas distributional patterns in the water column. Early veliger and competent larvae are concentrated in different parts of the
water column, probably related to their transport capacities. The upper layer of the water column at the Refugio site, unlike
the Guaitecas site, showed a stratified regime, which could affect larval density and larval length between the two sites.
Finally, our results suggest that Refugio may be a sink habitat for C. concholepas. 相似文献
120.