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91.
92.
Effective use of historical volumes of heterogeneous and multidimensional data is a major challenge, especially projects associated with potential applications of carbon emission ecosystems. Data science in these applications becomes tedious when such varied data are accumulated and or distributed in multiple domains. Design, development, and implementation of sustainable geological storages are crucial for managing carbon dioxide (CO2) emissions and its modeling process. The purpose of the research is to address major challenges and how best a robust “ontology-based multidimensional data warehousing and mining” approach can resolve issues associated with carbon ecosystems. The conceptualized relationships deduced among multiple domains, integration of domain ontologies, data mining, visualization, and interpretation artefacts are highlights of the study. Several data, plot, and map views are extracted from metadata storage for interpreting new knowledge on carbon emissions. Statistical mining models describe data attributes’ correlations, patterns, and trends that can help in predicting future forecast of CO2 emissions worldwide.  相似文献   
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94.

Purpose  

As one component of the German ecological environment observation, the Environmental Specimen Bank program was initiated in the mid-1980s. Under the program, representative specimens of marine, fresh water, and terrestrial ecosystems are sampled regularly and archived under chemically stable conditions. An initial characterization of the samples provides data regarding the status quo of the respective ecosystems. The aim of the present publication is to give insight into these real-time monitoring data, which have been generated for the last 10 to 20 years. This is done exemplarily for the heavy metals cadmium (Cd), mercury (Hg), and lead (Pb) in marine specimens of the Baltic and the North Sea.  相似文献   
95.

Background, aim, and scope  

Aquatic microcontaminants (MCs) comprise diverse chemical classes, such as pesticides, biocides, pharmaceuticals, consumer products, and industrial chemicals. For water pollution control and the evaluation of water protection measures, it is crucial to screen for MCs. However, the selection and prioritization of which MCs to screen for is rather difficult and complex. Existing methods usually are strongly limited because of a lack of screening regulations or unavailability of required data.  相似文献   
96.

Purpose  

Samples from the German Environmental Specimen Bank (ESB) covering particularly the years 1994–1996, 2000–2002, and 2006–2009 were analyzed for perfluorinated compounds (PFC; mainly C4–C13 carboxylic and sulfonic acids) to gain an overview on current PFC levels and patterns in marine, limnetic, and terrestrial biota; to assess their concentrations in different trophic levels; and to investigate whether risk management measures for PFC are successful.  相似文献   
97.
Translocation of carbohydrate from leaves to roots via phloem and reallocation from roots to leaves via xylem regulate the allocation of carbon (C) between above and belowground organs of trees. To quantitatively analyze effects of elevated ozone concentrations pO3 on the internal cycle of C, juvenile beech and spruce were grown in phytotrons and exposed to ambient and elevated pO3 (i.e. twice-ambient O3 levels, restricted to 〈 150 ppb) for two growing seasons. The translocation of C in the phloem and xylem was quantitatively studied by investigating the phloem/xylem-loading of sugars, the differentiation of stem conductive tissue and the hourly water flow through the stem. Results in the present study shown, elevated pO3 significantly decreased C translocation from shoot to roots in beech by reducing both sugar concentration in the phloem and conductive phloem area. Elevated pO3 also significantly decreased C reallocation from the roots to the shoot in beech by reducing both of sugar concentration in the xylem and transpiration rate. The adverse effects of elevated pO3 on C translocation in the phloem and xylem, however, were small in spruce. Contrasting to beech, spruce is less sensitive to elevated pO3, regarding to phloem differentiation and sugar concentrations in the phloem and xylem.  相似文献   
98.
The application of two different types of elemental sulfur (S0) was studied to evaluate the efficiency on bioleaching of heavy metals from contaminated sediments. Bioleaching tests were performed in suspension and in the solid-bed with a heavy metal contaminated sediment using commercial sulfur powder (technical sulfur) or a microbially produced sulfur waste (biological sulfur) as substrate for the indigenous sulfur-oxidizing bacteria and thus as acid source. Generally, using biological sulfur during suspension leaching yielded in considerably better results than technical sulfur. The equilibrium in acidification, sulfur oxidation and metal solubilization was reached already after 10-14 d of leaching depending upon the amount of sulfur added. The metal removal after 28 d of leaching was higher when biological sulfur was used. The biological sulfur added was oxidized with high rate, and no residual S0 was detectable in the sediment samples after leaching. The observed effects are attributable to the hydrophilic properties of the biologically produced sulfur particles resulting in an increased bioavailability for the Acidithiobacilli. In column experiments only poor effects on the kinetics of the leaching parameters were observed replacing technical sulfur by biological sulfur, and the overall metal removal was almost the same for both types of S0. Therefore, under the conditions of solid-bed leaching the rate of sulfur oxidation and metal solubilization is more strongly affected by transport phenomena than by microbial conversion processes attributed to different physicochemical properties of the sulfur sources. The results indicate that the application of biological sulfur provides a suitable means for improving the efficiency of suspension leaching treatments by shortening the leaching time. Solid-bed leaching treatments may benefit from the reuse of biological sulfur by reducing the costs for material and operating.  相似文献   
99.
The study aimed to elucidate the effect of elevated CO2 in short- and long-term experiments on the emission potential of carbonyls from mature oak (Quercus petraea) and hornbeam (Carpinus betulus). The trees were investigated using a canopy crane established in a mixed forest in Switzerland. Short-term CO2 experiments were performed on single leaves with a gas exchange measuring unit by increasing CO2 in the enclosure before and during the measurements. Long-term CO2 fumigation was performed for one vegetation period by a webFACE design. Short-term as well as long-term exposure of leaves resulted in no significant changes in carbonyl exchange in neither Q. petraea nor C. betulus. Carbonyl emission was not affected by stomatal closure under elevated CO2 levels. In contrast to the emission of isoprenoids from vegetation which is thought to be reduced at elevated atmospheric CO2, the exchange of carbonyls seems to be generally unaffected under these conditions.  相似文献   
100.
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