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91.
As a major biotic component of many lotic ecosystems, macrophytes consist a major component of running waters are often used as indicators within the European Water Framework Directive (WFD) to establish ecological quality. In this study, we investigated macrophyte community structure (e.g. composition, abundance and diversity) in Ceyhan River Basin located in the Southeastern Anatolian Region in Turkey. Data was collected during 2014–2015 from river sites located throughout the basin to evaluate the relationship between aquatic vegetation and river physico-chemical factors. The ecological status of the river basin was also calculated based on Macrophyte Biological Index for River (IBMR). In total, 33 macrophyta taxa were observed. According to their biological classification (life form), filamentous algae (FA), free floating (FF), floating leaved (FL) and submersed (S) macrophytes reached their maximum abundance value in summer, while emergent (E) macrophytes were at their maximum abundance in both summer and autumn. The ecological status of the Ceyhan River basin ranged from moderate to bad. The values found are reasonably comparable to IBMR scores recorded in rivers of other Mediterranean countries. IBMR index may be suitable to some extent to establish a basis for ecological quality assessment in Turkish River systems.  相似文献   
92.
Ecology-based tourism, which is integrated with nature, developed in environmentally conscious areas and enriched by different cultures, has become more important in the direction of extending tourism throughout the year. While the landscape values of the area are important functions for tourism activities to be carried out in natural characteristics, the preferences of the users are also important. Ecology-based tourism, which develops in connection with the concepts of intacteness, the protection-use balance and sustainability, and the demands and expectations of tourists, constitute the basis of our study. For this purpose, the study was carried out in Kumyaka, a small coastal neighborhood (village) of the county of Mudanya in the province Bursa, Turkey with important natural, historical and cultural assets. Fieldwork, field analysis, literature search, interviews with tourists coming to the field, interviews with the day trippers and survey work were conducted in the study. While evaluating the ecology-based tourism potential of the area, the demands and expectations of tourists have been taken into account together with the available area data. According to the results of the survey, tourists are mostly interested in having the most scenic value and quietness when choosing the area. The types of tourism that tourists most wanted to experience in the field were 42.38% culture tourism and 32.32% nature tourism. As a result of tourists’ demands and expectations, the tourism activities to be carried out in accordance with the possibilities of the area were examined and ecology based planning proposals and holistic planning approaches were developed.  相似文献   
93.
Increase in waste sludge disposal is always seen as a problem from the point of production industry. However, it is clear that the reuse and recycle of sewage sludge could be a serious economic input. The most important action should be to determine the sludge characterizations and direct the producers towards appropriate reuse and recycling opportunities. In this study, reuse method was examined to produce coal briquette, which will constitute an example for waste sludge. In order to make use of the waste sludge, five different coal briquette samples were produced by mixing powdered coal and bitumen together with waste sludge, at different ratios. The overall results indicated that the sample named CB3 having 70% powdered coal, 20% waste sludge, and 10% bitumen was found to be the optimum coal briquette among the other samples produced. The proximate analysis of the optimum briquette sample was carried out according to the Turkish standards and regulations and it was found out that the produced briquette coal can have commercial value with a gross calorific value of 30.03 MJ/kg and 7.30% ash content.  相似文献   
94.
Ultrasonic irradiation is considered an effective way to increase mass transfer between immiscible liquid–liquid phases in a heterogeneous system leading to faster transesterification and higher yield and saving excess methanol and catalyst. In this study, the transesteri?cation of hazelnut oil with methanol and ethanol was performed in the presence of potassium hydroxide or sodium methoxide as a catalyst using two types of ultrasonic irradiation with a probe (20 kHz, 200 W) and a bath (35 kHz, 400 W); a conventional production method was also used. The reaction time, alcohol:oil molar ratio, catalyst type (KOH or NaOCH3), and catalyst amount (wt.% of oil) were studied as experimental parameters. The highest methyl ester conversion was obtained as 98.12% by using ultrasonic probe at a 5:1 methanol:oil molar ratio with KOH 1 wt.% of oil as catalyst in 20-min reaction time at autogenous temperature. The application of ultrasonic irradiation by using a probe decreased the level of energy consumption, showing that this method may be a promising alternative compared with the conventional production method.  相似文献   
95.
96.
Acidophilic S-oxidising bacteria isolated from sulphur-rich deep caves (Frasassi, Italy), characterised by relatively low temperature, were tested for their ability to mobilise (semi-)metals from contaminated sediments. Sediment samples from two commercial Italian seaports were used to set up bioleaching experiments. The effect of different growth substrates was also investigated. Our experiments revealed that S-oxidising bacteria isolated from Frasassi caves have a high potential to remove As from contaminated marine sediments, as never reported before. Although As solubilisation efficiency was quite low (i.e. about 30%), only a small amount of As was associated with non-residual fractions of the sediment. On the contrary, the solubilisation efficiencies of Zn and Ni (20% and 10%, respectively) were lower than those previously obtained by the use of other acidophilic bacteria and mainly influenced by the experimental conditions rather than by the presence of the S-oxidising bacteria. Results presented here open new perspectives in bioleaching applications for the remediation of contaminated sediments. Indeed, microbial strains adapted to relatively low-temperature environments could improve sediment bioleaching at temperature regimes where mesophilic and thermophilic strains are not favoured. Such strains could be exploited for developing selective bioremediation procedures for sediments contaminated with As, to be applied in multistep biotreatment processes.  相似文献   
97.
The aim of this study was to determine the genotoxic risk of professional hairdressers in Ayd?n City, Turkey, through investigating the micronucleus frequencies in buccal mucosa epithelial cells. All the hairdresser working hairdresser area were included in the genotoxic risk group (GRG = 20) in Ayd?n City, Turkey. The control group (CG = 20) comprised healthy individuals matching the gender and age of the GRG. Buccal mucosal scraping from all the 40 subjects of GRG (10 women and 10 men) and CG (10 women and 10 men) was stained with Giemsa stain and observed under light microscope (×40) for the presence of micronuclei (M 10 N) and karyolysis, pyknosis, condensed chromatin, karyorrhexis, nuclear bud, and binucleates in the exfoliated epithelial cells. There are significance between the incidence of MN in GRG and CG (P = <0.005) using one-way ANOVA, Kolmogorov-Smirnov Z test, and Spearman Rank Correlation Tests.  相似文献   
98.
A food industry waste, almond shell, was pyrolyzed under three different environment static, nitrogen, and steam to produce bio-oil and its derivatives. The oil yield obtained at pyrolysis temperature of 600°C was 24.23% in a static atmosphere, whereas it increased to 27.25% and 33.05% in nitrogen and steam atmospheres, respectively. The bio-oil obtained under steam atmosphere is very efficient due to the production of high liquid and gas yields. Moreover, co-feeding steam during the pyrolysis altered the bio-oil structure by increasing the aliphatics and reducing the asphaltenes. Moreover, steam treatment also increases H/C and heating value of bio-oils. According to the obtained results, steam pyrolysis is an alternative option for future applications in refineries.  相似文献   
99.
Seaplanes have become an important tool along with rapidly developing technology in modern transportation for many countries related to sea. Considering the environmental evaluation for these aircraft, decreasing fossil fuels consumption and energy efficiency are important points for sustainability. For this purpose, in this study, first, the energy and exergy analyses based on the real data of a turboprop engine used in seaplane taken as the reference were performed. Then, new indicators developed for the sustainable propulsion index were examined and evaluated separately. The analyses were made for an altitude of 9000 ft and three different dead state temperatures of ?33°C, ?3°C, and 27°C. According to the analyses, while the average energy efficiencies were found to be 34.7%, 37.8%, and 40.7%, the average exergy efficiencies were found to be 19.24%, 21.25%, and 23.20%, respectively. In addition, the improvement potential due to irreversibility and entropy production for each case was also calculated and the results of the sustainable emission index were found to be very low. At the end of the study, the results were evaluated and some suggestions for the effective use of energy in the seaplanes were made.  相似文献   
100.
Quantitative assessment of human exposures and health effects due to air pollution involve detailed characterization of impacts of air quality on exposure and dose. A key challenge is to integrate these three components on a consistent spatial and temporal basis taking into account linkages and feedbacks. The current state-of-practice for such assessments is to exercise emission, meteorology, air quality, exposure, and dose models separately, and to link them together by using the output of one model as input to the subsequent downstream model. Quantification of variability and uncertainty has been an important topic in the exposure assessment community for a number of years. Variability refers to differences in the value of a quantity (e.g., exposure) over time, space, or among individuals. Uncertainty refers to lack of knowledge regarding the true value of a quantity. An emerging challenge is how to quantify variability and uncertainty in integrated assessments over the source-to-dose continuum by considering contributions from individual as well as linked components. For a case study of fine particulate matter (PM2.5) in North Carolina during July 2002, we characterize variability and uncertainty associated with each of the individual concentration, exposure and dose models that are linked, and use a conceptual framework to quantify and evaluate the implications of coupled model uncertainties. We find that the resulting overall uncertainties due to combined effects of both variability and uncertainty are smaller (usually by a factor of 3–4) than the crudely multiplied model-specific overall uncertainty ratios. Future research will need to examine the impact of potential dependencies among the model components by conducting a truly coupled modeling analysis.  相似文献   
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