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181.
Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fostering just and diverse futures for human and nonhuman life on Earth.  相似文献   
182.
Reactive Blending of Biodegradable Polymers: PLA and Starch   总被引:11,自引:0,他引:11  
Poly(lactic acid) (PLA) and starch are important biodegradable polymers. Mechanical properties of blends of PLA and starch using conventional processes were very poor because of incompatibility. In this study, PLA and starch were blended with a reactive agent during the extrusion process. The affects of the reactive blending were investigated and significant improvements were confirmed by measuring the tensile strength and elongation at break, IR spectra, and DSC.  相似文献   
183.
Currently there is a growing interest in developing novel bioproducts and biomaterials derived from renewable sources that can reduce the dependence on fossil fuel feedstock. In this study a protein concentrate from microalgae Botryococcus braunii residual biomass (MPC) from a biorefinery process was used as a biopolymer to develop ultrafine fibers by electrospinning. Experiments were designed to study the effect of different formulations of MPC, poly(ethylene oxide) and pH on morphology and diameter of fibers. The results indicated MPC fibers from acidic solutions prepared at pH 1 had smoother and smaller diameter than those fibers from alkaline solutions (pH 12). Moreover, under the conditions studied, it was conclude that pH and the concentration of MPC were the most significant factors in determining the diameter and morphology of the fibers obtained. Fourier transform infrared analysis showed there is a slight frequency shift for the secondary structure of MPC as induced by change in pH of the polymer solutions. Likely this change in the protein structure improved the physical chain entanglement in the polymer blend. The results of this work revealed a potential to develop fibers from MPC from residual biomass by a promising technique that may find many end-use applications.  相似文献   
184.
Quality improvement of acidic soil (with an initial pH of approximately 4.5) with respect to soil pH, exchangeable cations, organic matter content, and maize growth was attempted using natural (NSF) and calcined starfish (CSF). Acidic soil was amended with NSF and CSF in the range of 1 to 10 wt.% to improve soil pH, organic matter content, and exchangeable cations. Following the treatment, the soil pH was monitored for periods up to 3 months. The exchangeable cations were measured after 1 month of curing. After a curing period of 1 month, the maize growth experiment was performed with selected treated samples to evaluate the effectiveness of the treatment. The results show that 1 wt.% of NSF and CSF (700 and 900 °C) were required to increase the soil pH to a value higher than 7. In the case of CSF (900 °C), 1 wt.% was sufficient to increase the soil pH value to 9 due to the strong alkalinity in the treatment. No significant changes in soil pHs were observed after 7 days of curing and up to 3 months of curing. Upon treatment, the cation exchange capacity values significantly increased as compared to the untreated samples. The organic content of the samples increased upon NSF treatment, but it remains virtually unchanged upon CSF treatment. Maize growth was greater in the treated samples rather than the untreated samples, except for the samples treated with 1 and 3 wt.% CSF (900 °C), where maize growth was limited due to strong alkalinity. This indicates that the amelioration of acidic soil using natural and calcined starfish is beneficial for plant growth as long as the application rate does not produce alkaline conditions outside the optimal pH range for maize growth.  相似文献   
185.
Despite the large implications of the use of tropical land for exports (“land absorption”) on ecosystem services (ES) and global biodiversity conservation, the magnitude of these externalities is not known. We quantify the net value of ES lost in tropical countries as a result of cropland, forestland and pastureland absorption for exports after deducting ES gains through imports (“land displacement”). We find that net ES gains occur only in 7 out of the 41 countries and regions considered. We estimate global annual net losses of over 1.7 x 1012 international dollars (I$) (I$1.1 x 1012 if carbon-related services are not considered). After deducting the benefits from agricultural, forest and livestock rents in land replacing tropical forests, the net annual losses are I$1.3 and I$0.7 x 1012, respectively. The results highlight the large magnitude of tropical ES losses through international trade that are not compensated by the rents of land uses in absorbed land.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-016-0768-7) contains supplementary material, which is available to authorized users.  相似文献   
186.
Capturing of odorous compounds such as toluene vapor by a particulate-activated carbon adsorbent was investigated in a gas-solid cyclone, which is one type of mobile beds. The test cyclone was early modified with the post cyclone (PoC) and a spiral flow guide to the vortex finder. The proposed process may contribute to the reduction of gases and dust from industrial exhausts, especially when dealing with a low concentration of odorous elements and a large volume ofdust flow. In this device, the toluene capturing efficiency at a 400 ppm concentration rose up to 77.4% when using activated carbon (AC) particles with a median size of 27.03 microm. A maximum 96% of AC particles could be collected for reuse depending on the size and flow rate. The AC regenerated via thermal treatment showed an adsorption potential up to 66.7% throughout repeated tests.  相似文献   
187.
A turbulent wet scrubber was designed and developed to scrub particulate matter (PM) at micrometer and submicrometer levels from the effluent gas stream of an industrial coal furnace. Experiments were conducted to estimate the particle removal efficiency of the turbulent scrubber with different gas flow rates and liquid heads above the nozzle. Particles larger than 1 µm were removed very efficiently, at nearly 100%, depending upon the flow rate, the concentration of the dust-laden air stream, and the water level in the reservoir. Particles smaller than 1 µm were also removed to a greater extent at higher gas flow rates and for greater liquid heads. Pressure-drop studies were also carried out to estimate the energy consumed by the scrubber for the entire range of particle sizes distributed in the carrier gas. A maximum pressure drop of 217 mm H2O was observed for a liquid head of 36 cm and a gas flow rate of 7 m3/min. The number of transfer units (NTU) analysis for the efficiencies achieved by the turbulent scrubber over the range of particles also reveals that the contacting power achieved by the scrubber is better except for smaller particles. The turbulent scrubber is more competent for scrubbing particulate matter, in particular PM2.5, than other higher energy or conventional scrubbers, and is comparable to other wet scrubbers of its kind for the amount of energy spent.

Implications: The evaluation of the turbulent scrubber is done to add a novel scrubber in the list of wet scrubbers for industrial applications, yet simple in design, easy to operate, with better compactness, and with high efficiencies at lower energy consumption. Hence the turbulent scrubber can be used to combat particulate from industrial gaseous effluents and also has a scope to absorb gaseous pollutants if the gases are soluble in the medium used for particles capture.  相似文献   
188.
Probabilistic capture zones are combined with a regression model and used as buffer zones around wells for Tobit regression analysis to predict contaminant concentration of groundwater in an agricultural region. A backward transport equation, which is a mathematical model based on the physical processes of solute transport, is used to delineate probabilistic capture zones. The probabilistic capture zone defines the area where contaminant discharge can have a direct influence, with pertinent probability, on the quality of groundwater pumped from a well. Tobit regression analysis is used to find the relationship between independent regression variables and a dependent variable, which is contaminant concentration in this study. The capture zone and the regression are combined into a model, and its applicability for prediction of nitrate concentration is tested in a small agricultural basin in Chuncheon, Korea, which is occupied mainly by vegetation fields, orchards, and small barns. Three cases of Model 1, Model 2, and Model 3 are compared in which buffer zones are circles, capture zones with probability over 0.1, and capture zones divided into sections with different probabilities, respectively. The resulting regression model describes nitrate concentration in terms of selected independent variables. When the concentrations are calculated with the model, the best fit with the observed concentrations was in Model 3. This result supports the applicability of the method proposed in this study to prediction of contaminant concentration of groundwater.  相似文献   
189.
Reactive dyes account for one of the major sources of dye wastes in textile effluent. In this study, decolorization of the monoazo dye, Acid Orange 7 (AO7) by the Enterococcus faecalis strain ZL that isolated from a palm oil mill effluent treatment plant has been investigated. Decolorization efficiency of azo dye is greatly affected by the types of nutrients and the size of inoculum used. In this work, one-factor-at-a-time (method and response surface methodology (RSM) was applied to optimize these operational factors and also to study the combined interaction between them. Analysis of AO7 decolorization was done using Fourier transform infrared (FTIR) spectroscopy, desorption study, UV–Vis spectral analysis, field emission scanning electron microscopy (FESEM), and high performance liquid chromatography (HPLC). The optimum condition via RSM for the color removal of AO7 was found to be as follows: yeast extract, 0.1 %?w/v, glycerol concentration of 0.1 %?v/v, and inoculum density of 2.5 %?v/v at initial dye concentration of 100 mg/L at 37 °C. Decolorization efficiency of 98 % was achieved in only 5 h. The kinetic of AO7 decolorization was found to be first order with respect to dye concentration with a k value of 0.87/h. FTIR, desorption study, UV–Vis spectral analysis, FESEM, and HPLC findings indicated that the decolorization of AO7 was mainly due to the biosorption as well as biodegradation of the bacterial cells. In addition, HPLC analyses also showed the formation of sulfanilic acid as a possible degradation product of AO7 under facultative anaerobic condition. This study explored the ability of E. faecalis strain ZL in decolorizing AO7 by biosorption as well as biodegradation process.  相似文献   
190.
In this study, the effects of three widespread heavy metals, As(III), As(V) and Cd, and their binary mixtures on the proteomic profile in D. magna were examined to screen novel protein biomarkers using the two-dimensional gel electrophoresis method (2DE). Ten 20d daphnia were exposed to the LC20 concentrations for each of a total of 8 treatments, including the control, As(III), As(V), Cd, [As(III)+As(V)], [As(III)+Cd], [As(V)+Cd], and [As(III), As(V), Cd], for 24 h before protein isolation. Three replicates were performed for each treatment. These protein samples were employed for 2DE experiments with a pH gradient gel strip from pH 3 to pH 10. The protein spots were detected by a silver staining process and their intensities were analyzed by Progenesis software to discover the differentially expressed proteins (DEPs) in response to each heavy metal. A total of 117 differentially expressed proteins (DEPs) were found in daphnia responding to the 8 treatments and mapped onto a 2D proteome map, which provides some information of the molecular weight (MW) and pI value for each protein. All of these DEPs are considered as potential candidates for protein biomarkers in D. magna for detecting heavy metals in the aquatic ecosystem. Comparing the proteomic results among these treatments suggested that exposing D. magna to binary mixtures of heavy metals may result in some complex interactive molecular responses within them, rather than just the simple sum of the proteomic profiles of the individual chemicals, (As(III), As(V), and Cd).  相似文献   
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