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81.
The aim of this article is to evaluate selected tourism development strategies in Poland, in the context of strategic planning, stakeholders’ participation, and sustainable development principles. A questionnaire evaluation of strategy (44 questions) was established and based on measurement scales developed and validated by other authors in earlier studies. The five authors of the study rated 37 tourism development strategies in 13 provinces, 11 cities, 5 counties, 6 municipalities, and 2 other areas. Analysis revealed that they implement paradigms of sustainable development of tourism to only a small extent. Definitely higher quality is documented for higher levels of administrative division. The highest rated domains of the tourism development strategy in the examined documents are Strategic Planning Indicators and Implementation, Monitoring, and Evaluation.  相似文献   
82.
83.
Environmental Science and Pollution Research - The maximisation of the efficiency of the photovoltaic system is crucial in order to increase the competitiveness of this technology. Unfortunately,...  相似文献   
84.
The aim of study was to determine 9 organic acids in nine aboveground and seven wood-growing wild edible mushroom species originated from an area under the direct influence of a busy trunk road in Poland. The organic acids in the extracts of samples were identified by reversed-phase column liquid chromatography (RPLC). The presented results show that all the mushroom species were characterized by high variation in the profile and content of the analyzed acids. Each of mushroom species contained oxalic acid, the profiles of the other acids strictly depended on mushroom species. Among aboveground species, the highest total content of organic acids was found in Lepista gilva (267.5 ± 26.6 mg g?1 dry weight (DW)), while Laccaria amethystina was characterized by the lowest content (37.7 ± 6.5 mg g?1 DW). Within wood-growing species, the highest content of organic acids was determined in Flammulina velutipes (171.9 ± 26.7 mg g?1 DW), whereas the lowest content (34.2 ± 2.9 mg g?1 DW) of the studied acids was observed in Grifola frondosa.  相似文献   
85.
Crisis mapping is a legitimate component of both crisis informatics and disaster risk management. It has become an effective tool for humanitarian workers, especially after the earthquake in Haiti in 2010. Ushahidi is among the many mapping platforms on offer in the growing field of crisis mapping, and involves the application of crowdsourcing to create online and interactive maps of areas in turmoil. This paper presents the Crisis Map of the Czech Republic, which is the first such instrument to be deployed nationwide in Central Europe. It describes the methodologies used in the preparatory work phase and details some practices identified during the creation and actual employment of the map. In addition, the paper assesses its structure and technological architecture, as well as its potential possible development in the future. Lastly, it evaluates the utilisation of the Crisis Map during the floods in the Czech Republic in 2013.  相似文献   
86.
The paper presents the first report on the application of a lead film electrode for the determination of ultratrace concentrations of platinum. The procedure is based on preconcentration of the Pt(IV)-formaldehyde complexes at an in situ plated lead film electrode held at ?0.9 V (vs. Ag/AgCl), followed by a negatively sweeping differential pulse voltammetric scan. The composition of the supporting electrolyte, the influence of accumulation potential and time on the sensitivity of platinum responses are discussed. The detection limit of Pt(IV) with the accumulation time of 60 was equal to 9.2?×?10?12 mol L?1. The application of this method was tested by recovery of Pt(IV) from spiked environmental water samples.  相似文献   
87.
The content of arsenic (As) in mushrooms can vary depending on the concentration level of this metalloid in the soil/substrate. The present study evaluated the content of arsenic in Boletus badius fruiting bodies collected from polluted and non-polluted sites in relation to the content of this element in overgrown substrate. It was found that mushrooms from the arsenic-polluted sites contained mean concentrations from 49 to 450 mg As kg?1 dry matter (d.m.), with the greatest content found for specimens growing in close proximity of sludge deposits (490±20 mg As kg?1d.m.). The mean content of total arsenic in mushrooms from clean sites ranged from 0.03 to 0.37 mg kg?1 It was found that B. badius could tolerate arsenic in soil substrate at concentrations of up to 2500 mg kg?1, at least. In different years of investigation, shifts in particular arsenic forms, as well as a general increase in the accumulation of organic arsenic content, were observed. The results of this study clearly indicate that B. badius should not be collected for culinary purposes from any sites that may be affected by pollution.  相似文献   
88.
An analytical method for simultaneous determination of the active substance (chlorpyrifos) and its relevant impurity (sulfotep) in commercial pesticide formulations has been developed and validated. The proposed method entails extraction of the analytes from samples by sonication with acetone and analysis by gas chromatography-flame ionization detection (GC-FID). The proposed method was characterized by satisfactory accuracy and precision. The repeatability expressed as relative standard deviation (RSD) was lower than the acceptable values calculated from the modified Horwitz equation whereas individual recoveries were in the range of 98–102% and 80–120% for chlorpyrifos and sulfotep, respectively. The limit of quantification (LOQ) for the impurity (sulfotep) was 0.003 mg mL?1 corresponding to the maximum permitted level according to Food and Agricultural Organization of the United Nations (FAO) specifications for the active substance (chlorpyrifos) being 3 g kg?1 of the chlorpyrifos content found. The main advantage of the proposed method was a considerable reduction in the analysis time since both analytes were determined based on a single injection into the GC-FID. Analysis of real samples of commercial pesticide formulations confirmed fitness-for-purpose of the proposed method.  相似文献   
89.
The purpose of this study was an experimental investigation and a statistical evaluation of the influence of various additives in feed mixtures of broiler chickens on fatty acids content and their ratio in breast and thigh muscles. First feed additive consisted of narasin, nicarbasin and salinomycin sodium, and other five additives were of phytogenic origin. In vivo experiment was realized on the poultry experimental station with deep litter breeding system. A total of 300 one-day-old hybrid chickens Cobb 500 divided into six groups were used for the experiment. The experimental period was divided into four phases, i.e. Starter, Grower 1, Grower 2 and Final, according to the application of commercial feed mixture of soy cereal type. Additive substances used in feed mixtures were different for each group. Basic feed mixtures were equal for all groups. Fatty acid profile of breast and thigh muscles was measured by the method of FT IR Nicolet 6700. Investigated additive substances in the feed mixtures did not have statistically significant effect on fatty acid content and omega-6/omega-3 polyunsaturated fatty acid (PUFA) ratio in breast and thigh muscles. Strong statistically significant relation between omega-6 PUFAs and total PUFAs were proved by experiment. A relation between omega-3 PUFAs and total PUFAs was found only in the group with Biocitro additive.  相似文献   
90.
INTRODUCTION: Chlorinated ethanes and ethenes are among the most frequently detected organic pollutants of water. Their physicochemical properties are such that they can contaminate aquifers for decades. In favourable conditions, they can undergo degradation. In anaerobic conditions, chlorinated solvents can undergo reductive dechlorination. DEGRADATION PATHWAYS: Abiotic dechlorination is usually slower than microbial but abiotic dechlorination is usually complete. In favourable conditions, abiotic reactions bring significant contribution to natural attenuation processes. Abiotic agents that may enhance the reductive dechlorination of chlorinated ethanes and ethenes are zero-valent metals, sulphide minerals or green rusts. OXIDATION: At some sites, permanganate and Fenton's reagent can be used as remediation tool for oxidation of chlorinated ethanes and ethenes. SUMMARY: Nanoscale iron or bimetallic particles, due to high efficiency in degradation of chlorinated ethanes and ethenes, have gained much interest. They allow for rapid degradation of chlorinated ethanes and ethenes in water phase, but they also give benefit of treating dense non-aqueous phase liquid.  相似文献   
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