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891.
Environmental Science and Pollution Research - The worldwide occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic ecosystems is reason for public concern. These emerging...  相似文献   
892.
Environmental Science and Pollution Research - Socioeconomic and demographic factors, lifestyle and cultural characteristics may play an important role in the development of genetic damage. This...  相似文献   
893.
Journal of Material Cycles and Waste Management - In this work, the synthesis of biochar from several biomass wastes to act as matrix for urea was investigated. The objective was to select the most...  相似文献   
894.
Journal of Material Cycles and Waste Management - Discarded dry fig and raisin, which exporting companies have to claim and destroy, were subjected to batch dark fermentation at 37 °C...  相似文献   
895.
Journal of Material Cycles and Waste Management - Wood biomass fly ash can contribute to a more sustainable urban infrastructure, but requires efficient recycling strategies. This paper...  相似文献   
896.
Journal of Polymers and the Environment - Poly ε-caprolactone (PCL) synthesized by ring-opening polymerization method, and then it blended with polylactic acid (PLA). The blend was loaded with...  相似文献   
897.
Bivalve molluscs from the Western coast of Senegal were sampled and measured for their cadmium, copper and zinc concentrations. This part of Africa has not been studied as regards heavy metal concentrations in the molluscs. The collected species are two small African bivalve molluscs, living in the sand: Cardita ajar and Dosinia isocardia; the African mussel Perna perna which is the only mussel of this genus in the Western coast of Africa and the oyster Crassostrea gasar, which lives in mangroves attached to the rhizophores, in the intertidal zone. C. gasar and C. ajar present higher cadmium concentrations, respectively 6.82+/-0.54 and 13.77+/-0.80 microg Cd/g (d.w.) than the two other species (D. isocardia: 3.88+/-0.31 microg/g and P. perna 2.37+/-0.22 microg/g. Copper and zinc concentrations are in the range of the published values for C. gasar and P. perna collected elsewhere in Africa. The results suggest that cadmium may be present in high concentrations in Senegalese waters where upwellings occur.  相似文献   
898.
This study qualifies and quantifies the immobilization of Cd, Zn and Co, (used as models of bivalent metal ions due to their relevant toxicity) in filters of synthetic hydroxyapatite (HAP) [Ca5(PO4)3OH]. They were flushed with solutions containing Cd (1 x 10(-5)M), Zn and Co (1 x 10(-4)M) at constant pH (8.6) and ionic strength (0.01 M). The concentration of these metal ions in the outlet was measured by ICP-OEM spectroscopy. The software PHREEQC (version 2.4.2) was used to model sorption process and the potential effect of salinity (KCl), pH, alkalinity (NaHCO3) and hardness (CaCl2) over the efficiency of the treatment. Results showed an excellent retention capacity of HAP for Cd, Zn and Co. Sorption data were successfully described considering a mix model of surface complexation onto phosphate surface groups, ionic exchange in surface calcium sites and the precipitation of ZnO. Co exchange and surface complexation constants (Kex and Kc) were taken from previous experiments, while KexCd=0.32 and KcCd=0.63 were estimated from our modeling results. Predictive values of metal ion sorption show that: (a) an increase in hardness does not play a significant role in the retention capacity of these metals on HAP; (b) an increase in alkalinity promotes the precipitation of MeCO3 which could alter the hydrodynamic of the column; (c) a decrease in pH and an increase in salinity inhibit ZnO precipitation enhancing Zn and Cd adsorption and decreasing Co retention on HAP.  相似文献   
899.
The movement and degradation of pesticide residues in soils and groundwater are complex processes affected by soil physical, (bio)chemical, and hydrogeological properties, climatic conditions, and agricultural practices. This work presents a physically-based analytical model suitable for long-term predictions of pesticide concentrations in groundwater. The primary interest is to investigate the impact of soil environment, related physical and (bio)chemical processes, especially, volatilization, crop uptake, and agricultural practices on long-term vulnerability of groundwater to contamination by pesticides. The soil is separated into root and intermediate vadose zones, each with uniform properties. Transport in each soil zone is modeled on the basis of complete mixing, by spatial averaging the related point multiphase-transport partial differential equation (i.e., linear-reservoir models). Transport in the aquifer, however, is modeled by a two-dimensional advection-dispersion transport equation, considering adsorption and first-order decay rate. Vaporization in the soil is accounted for by assuming liquid-vapor phase partitioning using Henry's law, and vapor flux (volatilization) from the soil surface is modeled by diffusion through an air boundary layer. Sorption of liquid-phase solutes by crops is described by a linear relationship which is valid for first-order (passive) crop uptake. The model is applied to five pesticides (atrazine, bromacil, chlordane, heptachlor, and lindane), and the potential for pesticide contamination of groundwater is investigated for sandy and clayey soils. Simulation results show that groundwater contamination can be substantially reduced for clayey soil environments, where bio(chemical) degradation and volatilization are most efficient as natural loss pathways for the pesticides. Also, uptake by cross can be a significant mechanism for attenuating exposure levels in ground-water especially in a sandy soil environment, and for relatively persisting pesticides. Further, simulations indicate that changing agricultural practices can have a profound effect on vulnerability of groundwater to mobile and relatively persisting pesticides.  相似文献   
900.

Introduction

This article describes one experiment that studied the influence of Daytime Running Lamps (DRL) on pedestrian detection of turn indicators.

Method

An experimental device including one DRL and one turn indicator was used in order to determine Visual Reaction Times (VRT) of 148 observers in different situations involving turn indicator activation. Such situations were combinations of three main variables: color of DRL, separation between DRL and Turn Indicator, and observation angle.

Results

Significant changes in VRT were found depending on the configurations above, especially the observation angle and the color of DRL. This second result demonstrates that amber DRLs inhibit the detection of Turn Indicators.

Impact on industry

One of the main targets of this paper is to recommend that carmakers introduce only white DRLs on new vehicles. We also intend to advise regulatory bodies working on automotive regulation about the consequences of allowing amber DRLs and also about the danger of introducing constrains on the distance between DRL and Turn Indicator without further experimental evidences.  相似文献   
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