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81.
Hematocrit and hemoglobin concentration of yellowtail blood elevated more than 30% during severe hypoxia for 35 or 40 min. About 40% of the hematocrit elevation is considered to have been caused by erythrocyte supply from the spleen, and about 60% by hemoconcentration due to water shift out of the circulating plasma. Osmotic swelling of erythrocytes is considered not to have occurred, judging from the constant level in the saturation index of the blood.  相似文献   
82.
The efficiency of supercritical fluid extraction (SFE) for the isolation of polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) from sediments was investigated by comparing SFE with Soxhlet. Five sediments obtained from an international interlaboratory study were used as a test material. SFE was performed with an automatic system where extracted analytes were collected by solid-phase trapping using carbon mixed with Celite as an adsorbent. For the first time, SFE of the most toxic PCBs, coplanar PCBs, was studied with real sediment samples. The majority of PCBs investigated, a total of 38 congeners from tri- to decachlorinated, were quantitatively extracted from sediment by SFE with pure CO2 at pressure 400 atm and temperature 100 degrees C. Under these conditions a successful extraction was obtained also for PCDD/PCDFs except for hepta- and octachlorinated congeners. Copper powder added to the sediment efficiently prevented the transfer of sulfur from the sample during SFE. The TEQs of both PCDD/PCDFs and PCBs obtained by SFE corresponded well with those obtained by the Soxhlet-based method. The reproducibility of SFE was high for both groups.  相似文献   
83.
Community action has an increasingly prominent role in the debates surrounding transitions to sustainability. Initiatives such as community energy projects, community gardens, local food networks and car sharing clubs provide new spaces for sustainable consumption, and combinations of technological and social innovations. These initiatives, which are often driven by social good rather than by pure monetary motives, have been conceptualised as grassroots innovations. Previous research in grassroots innovations has largely focused on conceptualising such initiatives and analysing their potential for replication and diffusion; there has been less research in the politics involved in these initiatives. We examine grassroots innovations as forms of political engagement that is different from the 1970s’ alternative technology movements. Through an analysis of community-run Energy Cafés in the United Kingdom, we argue that while present-day grassroots innovations appear less explicitly political than their predecessors, they can still represent a form of political participation. Through the analytical lens of material politics, we investigate how Energy Cafés engage in diverse – explicit and implicit, more or less conscious – forms of political engagement. In particular, their work to “demystify” clients’ energy bills can unravel into various forms of advocacy and engagement with energy technologies and practices in the home. Some Energy Café practices also make space for a needs-driven approach that acknowledges the embeddedness of energy in the household and wider society.  相似文献   
84.
Water-swelling material (WSM) is a fluid sealant obtained by blending high-absorbency polymer, a filler, and a solvent by using a synthetic resin elastomer as the base material. In this research, we studied experimentally the composition of WSM, the extent of swelling, the strength of the WSM and the long-term performance of the swelling material used as a jointed water cutoff treatment material at waste landfill sites. One of the results was that adjusting the degree of etherification of the high-absorbency polymer, which is a component of the WSM, and the resin content of the synthetic elastomer contributed to improvement of the swelling of the sealant and the strength of the swelling material. Further, in long-term tests, the strength of the WSM tended to become stabilized and it was confirmed that it had sufficient pressure resistance for use in coastal landfill sites, where its application as a water cutoff treatment material is being considered.  相似文献   
85.
86.
The state of mixture of light-absorbing carbonaceous particles was investigated in relation to light absorption properties using electron microscopic examinations, black carbon (BC) analyses of quartz filter by thermal/optical reflectance (TOR) method, measurements with two continuous light-absorbing photometers at a suburban site of Tsukuba, about 60 km northeast of Tokyo. The volume fraction of water-soluble material (?) in individual particles is important for assessing particulate light-absorbing and/or scattering of atmospheric aerosols. The values of ? in BC particles were evaluated by electron micrographs before and after dialysis (extraction) of water-soluble material. The mass absorption coefficient (MAC in units of m2 g?1) tended to increase with increasing the average ? in BC particles with the radius range of 0.05–0.5 μm. Thus, our results indicate that coatings of water-soluble material around BC particles can enhance the absorption of solar radiation. Moreover, the single scattering albedo (SSA) will increase because a large amount of coating material will scatter more light.  相似文献   
87.
Total mercury (T-Hg) and selenium (Se) concentrations in liver, kidney and muscle from a pod of killer whales including five mature females and three calves stranded in the northern area of Japan were analyzed. In the mature female, contamination level of T-Hg in the liver sample (62.2+/-21.9 microg/wet g) was markedly higher than that in kidney sample and muscle sample. The molar ratio of T-Hg to Se in the liver sample was approximately 1, and those in the kidney and muscle samples were markedly lower than 1. These results suggest that the formation of HgSe compound increases the hepatic accumulation of mercury (Hg). In contrast, contamination level of T-Hg in the calf organs was much lower than that in the mature female organs. These results suggest that the transfer of Hg from the mother to the fetus via placenta and/or to calf via milk is trace.  相似文献   
88.
This study was carried out to determine the in vitro antimicrobial and antioxidant activities of the essential oil, seed oil, and methanolic extract of seed oil obtained from Laurus nobilis L. (Lauraceae). The methanolic extract of seed oil exhibited more effective antibacterial activity comparing to essential oil and seed oil, GC-MS analyses of the essential oil resulted in the identification of 25 compounds. 1.8-Cineol (44.72%), a-Terpinyl acetate (12.95%), Sabinene (12.82%) were the main components. The fatty acid composition was characterized with the high content of linoleic acid (40.79%) and lauric acid (38.08%). The 50% (IC50) inhibition activity of the essential oil on the free radical DPPH was determined as 94.655 mg ml(-1), whereas IC50 value of methanolic extract of seed oil was found unstable. In the case of the linoleic acid system, oxidation of linoleic acid was inhibited by essential oil and methanolic extract of seed oil, which showed 64.28 and 88.76% inhibition, respectively. The inhibition value of the methanolic extract of seed oil was quite close to the synthetic antioxidant BHT, 92.46% inhibition.  相似文献   
89.
To determine the properties of enzymes from bacteria that degrade polypropiolactone (PPL), we isolated 13 PPL-degrading bacteria from pond water, river water, and soil. Nine of these strains were identified as Acidovorax sp., three as Variovorax paradoxus, and one as Sphingomonas paucimobilis. All the isolates also degraded poly(3-hydroxybutyrate) (PHB). A PPL-degrading enzyme was purified to electrophoretical homogeneity from one of these bacteria, designated Acidovorax sp. TP4. The purified enzyme also degraded PHB. The molecular weight of the enzyme was estimated as about 50,000. The enzyme activity was inhibited by diisopropylfluorophosphate, dithiothreitol, and Triton X-100. The structural gene of the depolymerase was cloned in Escherichia coli. The nucleotide sequence of the cloned DNA fragment contained an open reading frame (1476 bp) specifying a protein with a deduced molecular weight of 50,961 (491 amino acids). The deduced overall sequence was very similar to that of a PHB depolymerase of Comamonas acidovorans YM1609. From these results it was concluded that the isolated PPL-degrading enzyme belongs to the class of PHB depolymerases. A conserved amino acid sequence, Gly-X1-Ser-X2-Gly (lipase box), was found at the N-terminal side of the amino acid sequence. Site-directed mutagenesis of the TP4 enzyme confirmed that 20Ser in the lipase box was essential for the enzyme activity. This is the first report of the isolation a PHB depolymerase from Acidovorax.  相似文献   
90.
One of the objectives of the European SUBZERO project was to study the influence of sweat evaporation and condensation on the heat transmission properties of cold protective clothing. With the sweating thermal manikin Coppelius, water vapour transfer through and water condensation in the clothing can be determined simultaneously with the thermal insulation. In this study, 4 cold protective ensembles, intended for use temperatures between 0 and -50 degrees C, were measured with the dry manikin and at 2 different sweating rates. In addition, the ensembles were measured with non-sweating thermal manikins and in wear trials.  相似文献   
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