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501.
This research was designed to examine the presence of mutagenic/carcinogenic compounds in airborne pollutants in the rubber industry using an integrated chemical/biological approach. Inhalable airborne particulate matter (PM-10: <10 μm) was collected in four rubber factories using a high-volume sampler equipped with a cascade impactor for particle fractionation. The organic extracts of two different fractions (0.5–10 μm and <0.5 μm) were examined for mutagenicity with the Ames test and for in vitro DNA-damaging activity in human leukocytes by single-cell microgel electrophoresis (Comet assay). The extracts were also studied by gas chromatography/mass spectrometry (GC/MS) for polycyclic aromatic hydrocarbon (PAH) content. Nitrosamines in ambient air were sampled on cartridges and analysed by GC with a thermal energy analyser (TEA) detector. Airborne volatile genotoxins were monitored in situ using a clastogenicity plant test (Tradescantia/micronuclei test). The results showed that airborne particulates were mainly very fine (<0.5 μm) and that trace amounts of genotoxic nitrosamines (N-nitrosodimethylamine: 0.10–0.98 μg/m3; N-nitrosomorpholine: 0.77–2.40 μg/m3) and PAH (total PAH: 0.34–11.35 μg/m3) were present in air samples. Some extracts, particularly those obtained from the finest fractions, were mutagenic with the Ames test and genotoxic with the Comet assay. In situ monitoring of volatile mutagens using the Tradescantia/micronuclei test gave positive results in two working environments. The results showed the applicability of this integrated chemical–biological approach for detecting volatile and non-volatile genotoxins and for monitoring genotoxic hazards in the rubber industry.  相似文献   
502.
This study monitored total atmospheric deposit (TAD) around a smelting plant in Ile-Ife, Nigeria to assess the contributions of the industry to Nigeria's air-shed pollution. Samples were collected for 12 consecutive months using an Australian model gauge, harvested after 30 d of exposure, filtered and dried to constant weights using oven. Monthly deposition rates were determined and elemental characterizations of the TAD samples were done using proton-induced X-ray emission technique. Results revealed that the monthly deposition rates ranged from 0.69 to 4.62 gm?3 and was more pronounced in Harmattan. Twenty-three elements were detected; their total elemental concentrations ranged from 1.23 to 13.63 mg m?3 with Fe having the highest concentrations, while Na has the least. Pearson correlation indicated that some elements have common sources and/or similar chemical properties; enrichment factor showed that Fe, Zn, Pb, Mn were extremely enriched in the study area, modified degree of contamination (3.75) and pollution load intensity (1.21) showed that the neighborhoods could be exposed to high air pollution related impacts. Positive matrix factorization model revealed three distinct sources: Smelting emission (63%), biomass burning (17%), and suspended input material emissions (21%). The study concluded that the smelting activities posed a great hazard to receptors around the smelting industry.  相似文献   
503.
《L'Anthropologie》2021,125(4):102914
Linking southeastern Europe and central Europe, the Danube Valley plays a key role in the models of the first colonization of Europe by anatomically modern humans about 40 thousand years ago (Danube Corridor hypothesis). The middle course of the river, the Carpathian Basin occupies a fundamental place in the search for archaeological evidences of the expansion of modern humans. Surveys carried out in northern Hungary in the last two decades have discovered numerous open-air sites whose lithic material can be attributed to the period concerned. Our excavations carried out in the region of Eger demonstrated the presence of the Aurignacian but also allowed the recognition of a macrolaminar industry of the Initial Upper Palaeolithic. The lithic material collected on the surface of the Andornaktálya 2 site provided rich assemblages of these two industries. The macrolaminar industry has techno-morphological connections with the leptolithic tools of Sokyrnytsia and Korolevo in Transcarpathian Ukraine. The Aurignacian industry has several characteristics in common with those of Košice-Barca and Seňa in southeastern Slovakia. Unfortunately, the chronological position of the macrolaminar and Aurignacian industries cannot be specified at the sites of the Eger region, although their age of Interpleniglacial seems evident from the stratigraphic considerations and the dating of the sediments. Despite these chronological inaccuracies, our results support the model, published by J.K. Kozłowski in 2010, of two waves of the immigration of modern humans across the Danube Corridor.  相似文献   
504.
Inulinase are industrial food enzymes which have gained much attention in recent scenario. In this study, Inulinase producing eight bacterial colonies were isolated and screened from three different plant root tubers soil sample. Among 8 inulinase producing colonies, the higher yielding colony was selected with 25.10?U/mL for further studies. The best inulinase producing colony was identified by partial 16S rRNA gene sequence as Bacillus sp. The crude inulinase was purified by using ammonium sulphate precipitation, dialysis and ion exchange chromatography on DEAE – sephacel and obtained 1.9 purification fold with total activity 293 U. The purified enzyme was subjected to characterization studies and it was found to be stable at 30–60?°C and optimum temperature was at 55?°C. The enzyme was stable at pH 3.0–7.0 and optimum pH was at 6.5. The Km and Vmax value for inulinase was found to be 0.117?mg/mL and 4.45?μmol?min?mg?1 respectively, demonstrate its greater affinity. Hence, this enzyme can be widely used for the production of fructose, and fructooligosaccharides, which are important ingredients in food and pharmaceutical industry.  相似文献   
505.
An historical overview of meetings of the International Seaweed Symposium is presented. A summary of attempts since 1952 to establish a seaweed industry in British Columbia is given. A brief review of recent developments in the area in relation to a seaweed industry is outlined.  相似文献   
506.
Electrical double layer capacitors (EDLCs) are nowadays considered one of the most important energy storage technologies. In recent years, great efforts have been made toward the development of novel materials, active and inactive, suitable for the realization of advanced EDLCs displaying higher performance, especially in terms of energy, compared to the state‐of‐the‐art devices. Nevertheless, the applicability of these materials in real devices and the industrial requirements related to the development of innovative EDLCs are not always properly addressed by the scientific community. This short review addresses these two fundamental aspects, with the aim to supply an updated set of information about the industrial requirements for the materials usable in commercial EDLCs. Additionally, the review also provides an updated overview about the present and estimated future market size of EDLCs as well as present and future applications of this technology addressing the market‐specific needs. This “application‐oriented” information is pivotal for a successful development and large‐scale production of advanced EDLCs.  相似文献   
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