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961.
《合并财务报表》会计准则的发布,使企业集团合并财务报表的编制更加规范。本文主要分析了该准则的合并理论和合并范围,指出合并理论应侧重实体理论,合并范围应强调实质性控制。  相似文献   
962.
963.
The basic principle of odor sampling from surface sources is based primarily on the amount of air obtained from a specific area of the ground, which acts as a source of malodorous compounds. Wind tunnels and flux chambers are often the only available, direct method of evaluating the odor fluxes from small area sources. There are currently no widely accepted chamber-based methods; thus, there is still a need for standardization of these methods to ensure accuracy and comparability. Previous research has established that there is a significant difference between the odor concentration values obtained using the Lindvall chamber and those obtained by a dynamic flow chamber. Thus, the present study compares sampling methods using a streaming chamber modeled on the Lindvall cover (using different wind speeds), a static chamber, and a direct sampling method without any screens. The volumes of chambers in the current work were similar, ~0.08 m3. This study was conducted at the mechanical-biological treatment plant in Poland. Samples were taken from a pile covered by the membrane. Measured odor concentration values were between 2 and 150 ouE/m3. Results of the study demonstrated that both chambers can be used interchangeably in the following conditions: odor concentration is below 60 ouE/m3, wind speed inside the Lindvall chamber is below 0.2 m/sec, and a flow value is below 0.011 m3/sec. Increasing the wind speed above the aforementioned value results in significant differences in the results obtained between those methods. In all experiments, the results of the concentration of odor in the samples using the static chamber were consistently higher than those from the samples measured in the Lindvall chamber. Lastly, the results of experiments were employed to determine a model function of the relationship between wind speed and odor concentration values.

Implications: Several researchers wrote that there are no widely accepted chamber-based methods. Also, there is still a need for standardization to ensure full comparability of these methods. The present study compared the existing methods to improve the standardization of area source sampling. The practical usefulness of the results was proving that both examined chambers can be used interchangeably. Statistically similar results were achieved while odor concentration was below 60 ouE/m3 and wind speed inside the Lindvall chamber was below 0.2 m/sec. Increasing wind speed over these values results in differences between these methods. A model function of relationship between wind speed and odor concentration value was determined.  相似文献   

964.
The aim of study was to determine the phytoextraction of rare earth elements (REEs) to roots, stems and leaves of five herbaceous plant species (Achillea millefolium L., Artemisia vulgaris L., Papaver rhoeas L., Taraxacum officinale and Tripleurospermum inodorum), growing in four areas located in close proximity to a road with varied traffic intensity. Additionally, the relationship between road traffic intensity, REE concentration in soil and the content of these elements in plant organs was estimated. A. vulgaris and P. rhoeas were able to effectively transport REEs in their leaves, independently of area collection. The highest content of REEs was observed in P. rhoeas leaves and T. inodorum roots. Generally, HREEs were accumulated in P. rhoeas roots and leaves and also in the stems of T. inodorum and T. officinale, whereas LREEs were accumulated in T. inodorum roots and T. officinale stems. It is worth underlining that there was a clear relationship between road traffic intensity and REE, HREE and LREE concentration in soil. No positive correlation was found between the concentration of these elements in soil and their content in plants, with the exception of T. officinale. An effective transport of REEs from the root system to leaves was observed, what points to the possible ability of some of the tested plant species to remove REEs from soils near roads.  相似文献   
965.
应用化学质量平衡模型解析烟台市污染源的排放贡献率   总被引:8,自引:0,他引:8  
根据烟台地区污染排放特点,应用化学质量平衡模型(CMB8)进行污染源解析分析,得出每个污染源对于受体地区颗粒物体样本的排放贡献率。最终的模型结果显示,建筑尘和居民烯煤锅炉排放,海洋尘和冶炼厂排放对于大气环境污染也有一定的贡献,以上分析可以为城市污染源治理提供一定的依据。  相似文献   
966.
Phorate (O,O-diethyl S-ethylthiomethyl phosphorodithioate) dissolved in aqueous solution was almost completely decomposed by ozonation to form various species within 10 minutes of reaction time for the experimental conditions examined in this research. The generation rate of sulfate was found to be fairly independent of solution pH value. However, the formation of phosphate and carbonate was more favorable for alkaline solutions where hydroxyl free radical is the primary oxidative species. The reaction rates increased with initial gaseous ozone concentrations, indicating the reaction was mass transfer-controlled within the experimental range of this research. Combining the analytical results by various instruments, including gas chromatograph equipped with an electron ionization detector (GC-EID), high performance liquid chromatography (HPLC), ion chromatography (IC), and total organic carbon (TOC), the temporal sequence of phorate ozonation was proposed in this study. The oxidation of sulfur atoms on the phosphorus-sulfur double bond or carbon-sulfur-carbon bond by ozonation was found to occur at first to form sulfate and various intermediates.  相似文献   
967.
Abstract

Potato sprouts could be a valuable resource of phytochemicals such as secondary plant metabolites, potential antioxidants and nutritive compounds. In this work, potato sprout extracts of five varieties were examined; they differed in major glycoalkaloid content, trypsin inhibitor activity, total polyphenol content and antioxidant activity, as well as in antimicrobial activity against Gram?+?and G???bacteria, and yeast. Sprouts of colored-fleshed tubers were characterized by higher trypsin inhibitor activity than sprouts of yellow potatoes. The strongest microorganism growth inhibition effect was observed for macerate with sprouts from the purple-fleshed Blaue Annelise variety against B. subtilis, whereas C. albicans yeasts were sensitive to macerates with sprouts from purple-fleshed Blue Congo and yellow-fleshed Vineta potato varieties.  相似文献   
968.
A great number of studies on the ambient levels of formaldehyde and other carbonyls in the urban rural and maritime atmospheres have been published because of their chemical and toxicological characteristics, and adverse health effects. Due to their toxicological effects, it was considered necessary to measure these compounds at different sites in the metropolitan area of Mexico City, and to calculate the total rate of photolytic constants and the photolytic lifetime of formaldehyde and acetaldehyde. Four sites were chosen. Sampling was carried out at different seasons and atmospheric conditions. The results indicated that formaldehyde was the most abundant carbonyl, followed by acetone and acetaldehyde. Data sets obtained from the 4 sites were chosen to calculate the total rate of photolysis and the photolytic lifetime for formaldehyde and acetaldehyde. Maximum photolytic rate values were obtained at the maximum actinic fluxes, as was to be expected.  相似文献   
969.
电子工业光致抗蚀剂乳化废水预处理试验研究   总被引:4,自引:0,他引:4  
研究了光致抗蚀剂乳化废水用硫酸和含钙辅助破乳分离出有机物沉淀的预处理工艺。确定了最合适的预处理工艺参数和流程;用GC/MS法分析了废水的组成和浓度,并探讨了有机物的去除机理。试验结果表明,pH值控制在3,辅助剂A的浓度为300mg/L、静置时间为60min时,是最合适的工艺条件,废水的CODcr值从15600mg/L下降到3542mg/L,CODcr的去除率达77.4%,投加辅助剂后既提高了有机物的去除率,又改善了沉淀物的过滤性能,从而有利于降低后续工艺的处理成本。  相似文献   
970.
研究提出了用磷酸钕(NdPO4)作为共沉淀捕集剂分离富集环境水样中的痕量Pb2 ,用火焰原子吸收光谱(FAAS)测定的方法.共沉淀受pH、NdCl3和H3PO4溶液用量的影响.结果显示,在溶液pH为3.2时,20 mL水样中加入5 mg/L NdCl3 2 mL、0.5 mol/L H3PO4 3 mL条件下,铅的加标回收率为96.6%~104.2%,方法的检测限为5.7×10-3 mg/L,水体中常见碱金属、碱土金属离子及阴离子在一定范围内不影响测定.  相似文献   
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