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21.
Calendula alata plants were tested for their potential to remove stable cesium and lead from solutions in a 15-day period. The plants were grown hydroponically and placed in solutions containing CsCl and Pb(C?H?O?)? at different concentrations (0.6, 2 and 5 mg l?1). When plants were incubated in CsCl solutions 46.84 ± 2.12%, 41.35 ± 1.59%, and 52.06 ± 1.02% cesium was found to be remediated after 15 days. Moreover, more than 99% lead was removed from the Pb(C?H?O?)? solution in all three concentrations after 15 days during the same period. When both CsCl and Pb(C?H?O?)? were supplemented together in the solution, 9.92 ± 1.22%, 45.56 ± 3.52%, and 46.16 ± 1.48% cesium and 95.30 ± 0.72%, 96.64 ± 0.30%, and 99.02 ± 0.04% lead were removed after 15 days. The present study suggests that hydroponically grown C. alata could be used as a potential candidate plant for phytoremediation of cesium and lead from solutions; however, plants were found to be more efficient for the remediation of lead than cesium.  相似文献   
22.

The current study proposes a novel and improved cigarette filtration design comprising cellulose nanofibers (CNFs) and powdered activated carbons (PACs) with different dry matter contents. The proposed filter samples were primarily analyzed to verify their applicability as cigarette filters via measurements and standard tests, such as SEM, BET, DSC, and airflow permeability analysis. The results were compared with the cellulose acetate (CA) sample used as a conventional cigarette filter. The preliminary results indicated noticeable improvement compared to the reference CA. Also, the cigarettes were tested using a smoking machine, and the filtered smoke was analyzed using GC–MS to evaluate the filters' performance in reducing the harmful substances present in the smoke. The results showed that the filters made of CNF and PAC significantly decreased the toxic substances compared with the reference but did not affect the nicotine substantially and therefore will not negatively impact the trance level of smokers.

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23.
Environmental Science and Pollution Research - Pentraxin 3 (PTX3) and ficolin are the plasma phase of pattern recognition receptors (PRRs) and can activate complement through classical and lectin...  相似文献   
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25.
The biosorption potential of processed walnut shell for Pb(II) and Cd(II) ions from aqueous solutions was explored. The effects of pH, contact time, initial ion concentration, and amount of dried adsorbent were studied in batch experiments. The maximum adsorption was achieved within the pH range 4.0–6.0. The equilibrium data were well fitted by the Langmuir isotherm model. The maximum monolayer adsorption capacities were found to be 32?g?kg?1 and 11.6?g?kg?1 for Pb(II) and Cd(II) ions, respectively. Kinetic data were best described by the pseudo-second-order model. The structural features of the adsorbent were characterized by Fourier transform infrared spectroscopy, which confirmed the involvement of hydroxyl (–OH), carboxyl (–COO), and carbonyl (C=O) groups in metal sorption. This readily available adsorbent is efficient in the uptake of Pb(II) and Cd(II) ions from an aqueous solution and could be used for the treatment of wastewater streams bearing these metal ions.  相似文献   
26.
• Synthesis of NS-CNTS is used in a high desulfurization performance. • Synthesizing NS-CNT is considered as a novel adsorbent from low-cost precursors. • A high sulfur removal capacity for NS-CNT is attained compared with recent works. Herein, nitrogen and sulfur co-doped carbon nanotubes (NS-CNT) adsorbents were synthesized via the chemical vapor deposition technique at 1000°C by employing the camphor, urea and sulfur trioxide pyridine. In this study, desulfurization of two types of mercaptans (dibenzothiophene (DBT) and tertiary butyl mercaptan (TBM) as nonlinear and linear forms of mercaptan) was studied. In this regard, a maximum capacity of NS-CNT was obtained as 106.9 and 79.4 mg/g and also the removal efficiencies of 98.6% and 88.3% were achieved after 4 h at 298K and 0.9 g of NS-CNT for DBT and TBM, respectively. Characterization of the NS-CNTs was carried out through exploiting scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and elemental analysis (CHN). The isotherm equilibrium data could be ascribed to the Freundlich nonlinear regression form and the kinetic data was fitted by nonlinear form of the pseudo second order model. The negative values of ΔS0, ΔH0 and ΔG0 specify that the adsorption of both types of mercaptans was a natural exothermic process with a reduced entropy. Maintenance of more than 96% of the adsorption capacity even after nine cycles suggest the NS-CNT as a superior adsorbent for mercaptans removal in the industry. Density functional theory (DFT) calculations were also performed to peruse the effects of S/N co-doping and carbon monovacancy defects in CNTs toward the adsorption of DBT and TBM.  相似文献   
27.
Environment, Development and Sustainability - In this research, 17 implications of changing cropping patterns (CP) to low water demand plants (LWDPs) were identified. Then, the experts were asked...  相似文献   
28.
Abstract

In this study, the preparation and characterization of haloxyfop-R-methyl herbicide loaded in poly(methylmethacrylate) (PMMA) nano-capsules by emulsion polymerization and its release behavior were investigated. The chemical characterizations of PMMA/haloxyfop-R-methyl nano-capsules were confirmed by FT-IR spectroscopy method, and the surface morphology was studied by field emission scanning electron microscopy and transmission electron microscopy. Also, the herbicide loading and encapsulation efficiency were analyzed for the herbicide-loaded nano-capsules. The release rate of PMMA/haloxyfop-R-methyl nano-capsules was determined by UV-visible spectroscopy. The thermal properties and thermal stability of nano-capsules were explored by the thermal gravimetric analysis method. The diameter of the nano-capsules was in the range of 100–300?nm. Increasing the amount of herbicide in nano-formulations significantly affected the surface of the nano-capsules and reduced their surface smoothness. Triton-X100 was identified as the best surfactant for the preparation of nano-capsules, and the sample containing the lowest herbicide content showed the best performance in terms of encapsulation and loading efficiency. This sample showed a steady-state release rate during the six days.  相似文献   
29.
A former natural gas processing station is impacted with total petroleum hydrocarbons (TPH) and benzene. Remedial process optimization (RPO) was conducted to evaluate the effectiveness of the historical air sparging/soil vapor extraction (AS/SVE) system and the current groundwater extraction and treatment system. The RPO indicated that both remedial activities offered no further benefit in meeting remediation goals. Instead, an in situ chemical oxidation (ISCO) system was recommended. Ozone was selected, and the results of a bench test indicated that the ozone demand was 8 to 12 mg ozone/mg TPH and that secondary by‐products would include hexavalent chromium and bromate. A capture zone analysis was conducted through groundwater flow modeling (MODFLOW) to ensure containment of the injected oxidant using the existing groundwater extraction system. Results of a pilot study indicated that the optimum frequency of ozone sparging is 60 minutes in order to reach a maximum radius of influence of 20 feet. TPH concentrations within the treatment zone decreased by 97 percent over two months of ozone sparging. Concentrations of hexavalent chromium and bromate increased from nondetect to 44 and 110 mg/L, respectively, during the ozone sparging but attenuated to nondetectable concentrations within three months of system shut down. ©2016 Wiley Periodicals, Inc.  相似文献   
30.
Environmental Science and Pollution Research - This study was conducted in order to assess the exposure to bacterial and fungal bioaerosols in the air of waterpipe cafés (AWPCs), in the hose...  相似文献   
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