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71.
Environmental Science and Pollution Research - Carbon dioxide emission and climatic variation have a detrimental influence on the atmosphere as well as on agriculture production. The key aim of the...  相似文献   
72.
Environmental Science and Pollution Research - Petroleum, coal, and natural gas reservoir were depleting continuously due to an increase in industrialization, which enforced study to identify...  相似文献   
73.
This research work aims to investigate the synergistic effect of pozzolanic materials such as oil palm ash (OPA) and oil palm empty fruit bunch (OPEFB) on the developed hybrid polymer composites. The OPEFB and OPA fillers of different particle sizes (250, 150, and 75 µm) were mixed at OPEFB:OPA ratios of (0:100; 20:80; 40:60; 60:40; 80:20 and 100:0) and incorporated into an unsaturated polyester resin. Furthermore, both mechanical and morphological properties of the composites were analyzed and it was found that tensile, flexural, and impact properties were significantly improved at OPEFB:OPA of 75 µm particle size hybridization of the polymer. The increase of OPEFB to OPA filler ratio up to 80:20 significantly improved the tensile properties of the composites while 40:60 ratio of 75 µm gave the optimum filler ratio to obtain the highest flexural and impact properties of the composites among all studied samples. Scanning electron micrograph images showed strong particle dispersion of the embedded fillers with resin which explained the excellent mechanical strength enhancement of the composite.  相似文献   
74.
75.
Environmental Science and Pollution Research - This study assessed the economic value of public urban green spaces (UGSs) in Kuala Lumpur (KL) city by using the hedonic price method (HPM). It...  相似文献   
76.
The potential of base treated Shorea dasyphylla (BTSD) sawdust for Acid Blue 25 (AB 25) adsorption was investigated in a batch adsorption process. Various physiochemical parameters such as pH, stirring rate, dosage, concentration, contact time and temperature were studied. The adsorbent was characterized with Fourier transform infrared spectrophotometer, scanning electron microscope and Brunauer, Emmett and Teller analysis. The optimum conditions for AB 25 adsorption were pH 2, stirring rate 500 r/min, adsorbent dosage 0.10 g and contact time 60 min. The pseudo second-order model showed the best conformity to the kinetic data. The equilibrium adsorption of AB 25 was described by Freundlich and Langmuir, with the latter found to agree well with the isotherm model. The maximum monolayer adsorption capacity of BTSD was 24.39 mg/g at 300 K, estimated from the Langmuir model. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that AB 25 adsorption was spontaneous and exothermic.  相似文献   
77.
A modified hydrophilic penta-bismuth hepta-oxide nitrate (Bi5O7NO3) surface was synthesized via a precipitation method using TiO2 and Ag as modified agents. The synthesized product was characterized by different analytical techniques. The removal efficiency was evaluated using mono-and di-sulphonated azo dyes as model pollutants. Different kinetic, isotherm and diffusion models were chosen to describe the adsorption process. X-ray photoelectron spectroscopy (XPS) results revealed no noticeable differences in the chemical states of modified adsorbent when compared to pure Bi5O7NO3;however, the presence of hydrophilic centres such as TiO2 and Ag developed positively charged surface groups and improved its adsorption performance to a wide range of azo dyes. Dyes removal was found to be a function of adsorbent dosage, initial dye concentration, solution pH and temperature. The reduction of Langmuir 1,2-mixed order kinetics to the second or first-order kinetics could be successfully used to describe the adsorption of dyes onto the modified adsorbent. Mass transfer can be described by intra-particle diffusion at a certain stage, but it was not the rate limiting step that controlled the adsorption process. Homogenous behavior of adsorbent surface can be explored by applying Langmuir isotherm to fit the adsorption data.  相似文献   
78.
In the current study, the chemistry of fresh and stored rainwater of Thar Desert, Pakistan, was estimated during two consecutive monsoon periods. The present research deals with the variation in physicochemical parameters, total arsenic (Ast), inorganic arsenic species (Asi, AsV, AsIII), and fluoride (F?) in stored rainwater (SRW) at different time intervals (1 week to 3 months). The pH of fresh rainwater (FRW) samples showed slightly acidic to neutral in nature (6.08–7.06) which were inconsistent with the reference pH value (5.6) of rainwater. The resulted data indicated that Ast and F? levels in SRW were enhanced with time duration. The levels of Ast and F? in SRW after different time intervals were found in the range of 194–683 μg/L and 10–35.4 mg/L, respectively. The values of Ast and F? were 20–70 and 7–24 times higher than those of WHO permissible limits, 10 μg/L and 1.5 mg/L, respectively. The AsIII was dominant species in SRW, which corresponds to >60 % of Asi. The characteristics of the SRW revealed an unacceptable quality to consume for drinking and agricultural purposes in the studied area.  相似文献   
79.
Mangrove forests in the tropics and subtropics grow in saline sediments in coastal and estuarine environments. Preservation of mangrove forests is important for many reasons, including the prevention of coastal erosion and seawater intrusion; the provision of spawning, nursery, and feeding grounds of diverse marine biota; and for direct use (such as firewood, charcoal, and construction material)—all of which benefit the sustainability of local communities. However, for many mangrove areas of the world, unsustainable resource utilization and the profit orientation of communities have often led to rapid and severe mangrove loss with serious consequences. The mangrove forests of the Takalar District, South Sulawesi, are studied here as a case area that has suffered from degradation and declining spatial extent during recent decades. On the basis of a post-classification comparison of change detection from satellite imagery and a survey of households, we provide an estimate of the mangrove change in the Takalar District during 1979–2011 and the consequences of those changes. Mangrove forest areas were reduced by 66.05 % (3344 hectares) during the 33-year period of analysis, and the biggest annual negative change in dense mangrove forest cover (8.37 %) occurred during the period 2006–2011. The changes were caused mainly by the mangrove clearing and conversion to aquaculture, and consequences have been increasing forest degradation, coastal abrasion, seawater intrusion, a decline in fish capture, a reduction in juvenile shrimp and milkfish, and outbreaks of shrimp disease. On the other hand, the clearing and impoundment of mangrove forests for shrimp and seaweed culture have provided a source of foreign exchange and new opportunities for employment in the study area.  相似文献   
80.
Microalgae biomass is well known as a potential sustainable product for bio-based industry, which has reported encountering numerous difficulties during biomass harvesting and recovering. This study examined the effect of pH (5–12) and alum dosage (30–180 mg/L) for microalgae Botryococcus sp. harvested via flocculation technique. The optimum pH condition for Botryococcus sp. harvesting was measured to be 9.2, and the alum dosage was 100 mg/L. Both optimum values successfully harvested up to 95% microalgae biomass. This study revealed that flocculation efficiencies for alum are highly dependent on the range of pH and coagulant dosage that were applied during the process. Use of flocculation technique with alum as a coagulant represents a convenient technique for Botryococcus sp. biomass harvesting and is recommended for use in both small- and large-scale biomass industries.  相似文献   
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