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101.
Edible mushrooms (Albatrellus ovinus, Boletus edulis, Clitocybe odora, Gomphidius glutinosus, Leccinum scabrum, Leccinum versipelle, Lycoperdon perlatum, Suillus bovinus, Suillus luteus, and Xerocomus subtomentosus) collected from unpolluted areas of the city of Umeå and its outskirts in the northern part of Sweden were examined for contents of toxic metallic elements (Cd, Pb, and Ag) and essential macro- and microelements (K, Na, Ca, Mg, Cu, Fe, Mn, and Zn) using a validated method and a final measurement by flame atomic absorption spectroscopy (F-AAS). The median values of the toxic metallic element concentrations (in mg kg?1 dry biomass, db) ranged from: 0.12–3.9, 0.46–5.1, and 0.91–6.2 for Ag, Cd and Pb, respectively. For the essential metallic elements, the median values of concentrations ranged from: 24000–58000, 15–2000, 59–610, 520–1900, 2.0–97, 16–150, 15–120, and 4.3–26 mg kg?1 db for K, Na, Ca, Mg, Cu, Zn, Fe, and Mn, respectively. The baseline concentrations of the metallic elements determined in mushrooms were mainly affected by the fungal species. The assessed probable maximal dietary intake of Cd (0.002 mg kg?1 body mass) solely from a mushroom meal was only slightly below a revised value of the tolerable weekly intake for this element, while for Pb (0.003 mg kg?1 body mass) it was tenfold below the provisionally tolerable weekly intake.  相似文献   
102.
The paper presents a new sampling method for studying in-body radioactive contamination by bone-seeking radionuclides such as 90Sr, 239+240Pu, 238Pu, 241Am and selected gamma-emitters, in human bones. The presented results were obtained for samples retrieved from routine surgeries, namely knee or hip joints replacements with implants, performed on individuals from Southern Poland. This allowed to collect representative sets of general public samples. The applied analytical radiochemical procedure for bone matrix is described in details. Due to low concentrations of 238Pu the ratio of Pu isotopes which might be used for Pu source identification is obtained only as upper limits other then global fallout (for example Chernobyl) origin of Pu. Calculated concentrations of radioisotopes are comparable to the existing data from post-mortem studies on human bones retrieved from autopsy or exhumations. Human bones removed during knee or hip joint surgery provide a simple and ethical way for obtaining samples for plutonium, americium and 90Sr in-body contamination studies in general public.  相似文献   
103.
Fruiting bodies of fungi belonging to more than 70 species were collected within a few thousand square meter area of one forest during 2006 and 2007. The soil profile was collected to check the cumulative deposition of 137Cs, which was relatively high, equal to 64 ± 2 kBq/m2 (calculated for October 2006). The majority of this activity was in the first 6 cm. Fruitbodies were analyzed for radiocesium and 40K by means of gamma-spectrometry. The highest 137Cs activity was 54.1 ± 0.7 kBq/kg (dry weight) for a sample of Lactarius helvus collected in 2006. The results for 2006 were higher than those for 2007. In a few cases the traces of short-lived (T1/2 = 2.06 a) 134Cs were still found in samples. The importance of mycorrhizal fungi for radiocesium accumulation is confirmed. The differences in activity among the species are discussed in relation to observations and predictions from previous studies, where the change in relative accumulation between fruiting bodies of different species was at least partially explained by the differences in the depth of the mycelium localization in a litter/soil system. It is concluded that in some cases, such as Boletus edulis and Xerocomus badius, this prediction is fulfilled and therefore this explanation confirmed.  相似文献   
104.
ABSTRACT

Lead (Pb), cadmium (Cd), and mercury (Hg) contents in ten species of edible mushrooms in Trako??an, Croatia were determined. In addition, the similarity between the studied species was determined by cluster analysis. The caps and stipes of the fruiting bodies were analysed separately. The analyses were carried out by inductively coupled plasma - optical emission spectrometry (ICP-OES). The greatest mean lead concentrations of 1.91 and 1.60 mg kg ?1 were determined in caps and stipes of Macrolepiota procera. The greatest mean concentrations of cadmium (3.23 and 2.24 mg kg?1) were determined in caps and stipes of Agaricus campestris and of mercury (2.56 and 2.35 mg kg?1) in Boletus edulis. In terms of the anatomical parts of the fruiting body (cap-stipe), a considerably greater concentration of the analysed elements was found in the cap for all mushroom species. According to calculated bio-concentration factors, all the examined species were found to be bio-accumulators of Cd and Hg. On the basis of the accumulation of the studied metals, great similarity of mushroom species belonging to the same genus and partial similarity of species of the same ecological affiliation was obtained by cluster analysis.  相似文献   
105.
The aim of the study was to develop a set of curricula for teaching Occupational Safety and Ergonomics at colleges and universities of various types, aimed at equipping students with knowledge and skills and at shaping active attitudes towards the practical application of the acquired knowledge in their future working lives. On the basis of the analysis of the curricula at Polish and foreign colleges and universities, a set (canon) of educational contents constituting a common practice in the academic teaching of Occupational Safety and Ergonomics was established. Then, a convenient for teaching this subject classification of university specialisations in Poland was introduced. This led to identifying and defining a taxonomic unit called here an educational profile. Next, curriculum minima for the developed profiles were defined objectively. To achieve this aim, the set of educational contents was ranked by university teachers and specialists in occupational safety and ergonomics. Each part of the educational contents (subject) was ranked on a 10-point scale in relation to each educational profile. The results of this ranking led to formulating sets of educational contents for each educational profile. On this basis, a repertoire of curricula (6 curricula, in 2 hour-by-hour versions each) was prepared, with methodological guidelines for lecturers. The results of the study were presented in the form of a manual for academic authorities.  相似文献   
106.
Three selected aspects of vehicle active safety are presented in this article: (a) modeling the driver and the driver–vehicle environment system, (b) the dynamic aspects of vehicle rollover, and (c) an analysis of the process of passing. Sample solutions and results show the need for further research in the field of vehicle safety in order to lower the probability of drivers, passengers, and other road users being involved in road accidents.  相似文献   
107.
Pseudomorphs of barite (BaSO4) and Cd-rich ZnS after whewellite (CaC2O4·H2O) occur within remnants of Scots pine bark tissues in the peat layer of a poor fen located near a zinc smelter in south Poland. A two-step formation of the pseudomorphs is postulated based on SEM observations: (1) complete dissolution of whewellite, possibly caused by oxalotrophic bacteria, and (2) subsequent bacterially induced precipitation of barite and spheroidal aggregates of ZnS together with galena (PbS) in voids left by the dissolved whewellite crystals. Local increase in pH due to microbial degradation of whewellite, elevated concentrations of Zn(II) and Ba(II) in pore water due to the decomposition of atmospheric particles of sphalerite and barite in the acidic (pH 3.5–3.8) environment, oxidation of S species during drying and rewetting of the peat layer, and subsequent partial reduction of sulfate anions by sulfur-reducing bacteria were all factors likely involved in the crystallization of ZnS and barite in the microenvironment of the post-whewellite voids.  相似文献   
108.
20世纪90年代波兰的政局发生了变革,由此所带来的农业转型对农业土地利用结构产生了根本性的改变.随着饲料作物比例的下降,粮食作物的比重相应地增加.此外,化学肥料的使用也相应减少了.在畜牧业中,牲畜存栏数表现出了急剧下降,这也导致了有机肥使用量的降低.耕作模式的改变和较低的肥料使用水平使土壤中的有机物含量下降,这有可能使土壤质量下降.由于在大波兰地区广泛存在轻质土壤,而且这类土壤中的养分可以很容易地被淋溶到地下水中,因此上述现象在该地区表现得极为突出.研究发现,在农业景观中的许多负面影响可以通过建立农田防护林带予以缓和.我们的结论是农田防护林带可以有效地控制流域的养分流失.  相似文献   
109.
110.
The nitroaromatic compounds 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT) and 2,4-dinitroanisole (DNAN) are potential environmental contaminants and their transformations under a variety of environmental conditions are consequently of great interest. One possible method to safely degrade these nitrocompounds is alkaline hydrolysis. A mechanism of the initial stages of this reaction was investigated computationally. Simulations of UV-VIS and NMR spectra for this mechanism were also produced. The results obtained were compared to available experimental data on the alkaline hydrolysis of TNT and suggest that the formation of Meisenheimer complexes and an anion of TNT are potential first-step intermediates in the reaction path. As the reaction proceeds, computational results indicate that polynegative complexes dominate the degradation pathway, followed by cycles of carbon chain opening and breaking. A second possible pathway was identified that leads to polymeric products through Janovsky complex formation. Results from this study indicate that the order of increasing resistance to alkaline hydrolysis is TNT, DNT and DNAN.  相似文献   
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