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551.
Since the adoption of ISO 14001, companies have examined the standard and considered certification. Although the framework is useful and enhancing environmental management systems is beneficial, the adoption of ISO 14001 alone will not provide maximum company benefits. Companies must strive for an improvement in environmental performance and financial performance that can be accomplished only through significant changes in corporate culture, structure, and systems. By developing core capabilities such as skills and knowledge, physical technical systems, managerial systems, and values and norms, companies can develop organizational learning to increase sustainable competitive advantage. This article examines how the ISO 14000 series of standards can be used to improve organizational learning and environmental management. 相似文献
552.
Experimental study was performed on a single basin active solar distillation system augmented with a solar collector using evacuated solar tubes. Field tests were conducted over several days under the climatic conditions of West Texas to evaluate the effect evacuated solar tubes have on the daily distillate yield rate. To investigate the feasibility of the solar tubes, active and passive solar stills with and without exterior insulation were examined. The maximum daily production rate for the active distillation system using evacuated solar tubes and the passive distillation system was 3.6 and 1.4 kg/m2day, respectively. The results showed the augmentation of the still with evacuated solar tubes increased its production capacity by a factor of 2.63. It also increased the maximum temperature of the water in the still basin by at least 20 °C. Economic analysis shows that it is feasible to use evacuated tubular collector coupled solar still as an alternative means for reclaiming water in farmlands with a payback period of approximately 6 years. 相似文献
553.
Allison H. Roy William D. Shuster 《Journal of the American Water Resources Association》2009,45(1):198-209
Abstract: Although total impervious area (TIA) is often used as an indicator of urban disturbance, recent studies suggest that the subset of impervious surfaces that route stormwater runoff directly to streams via stormwater pipes, called directly connected impervious area (DCIA), may be a better predictor of stream ecosystem alteration. We evaluated the differences between TIA and DCIA in the Shepherd Creek catchment, a small (1.85‐km2), suburban basin in Cincinnati, Ohio. Imperviousness determinations were calculated based on publicly available geographic information system (GIS) data and parcel‐scale field assessments, and these direct assessments were compared to DCIA calculated from published, empirical relationships. Impervious and semi‐impervious area comprised 13.1% of the catchment area, with 56.3% of the impervious area connected. When summarized by subcatchments (0.26‐1.85 km2), TIA measured in the field (11‐23%) was considerably higher than that calculated from the National Land Cover Data Imperviousness Layer (7‐18%). In contrast, TIA calculated based on aerial photos was similar to TIA calculated from field assessments, thus indicating that photo interpretation may be adequate for catchment‐scale (>25 ha) TIA determinations. While these GIS data sources can be used to calculate TIA, on‐site assessments were necessary to accurately determine DCIA within residential parcels. There was a wide variation in percent connectivity across parcels, and, subsequently, DCIA was not accurately predicted from empirical relationships with TIA. We discuss applications of DCIA data that highlight the importance of parcel‐scale field assessments for managing suburban watersheds. 相似文献
554.
Roy Cerqueti Catherine Deffains-Crapsky Saverio Storani 《Corporate Social Responsibility and Environmental Management》2023,30(4):1965-1986
In the context of green finance, minibonds play a crucial role. This financial instrument was introduced in 2012 as a valid alternative to bank credit for corporate financing, aimed mainly at small and medium-sized enterprises. Minibonds also represent useful support for implementing the ecological transaction agreed upon in COP 21, held in 2015 in Paris. Indeed, as of 2017, this instrument has been expanded from an environmental perspective by allowing the issuance of green minibonds. This article contributes to the debate on minibonds and the companies issuing them. Specifically, it proposes a cluster analysis approach for comparing the issuance level of minibonds in 2016 and the subsequent performances of the issuing companies in the triennium 2017–2019. Performance is divided into three macrocategories: profitability, productivity, and growth opportunities. The results suggest a nonlinear connection between the variables of interest, showing heterogeneous effects of minibonds on performance. However, the statistical data analysis seems to establish a positive relationship between minibonds' issuance level and companies' performance. 相似文献
555.
Felix Kienast Janine Bolliger Marion Potschin Rudolf S. de Groot Peter H. Verburg Iris Heller Dirk Wascher Roy Haines-Young 《Environmental management》2009,44(6):1099-1120
We examine the advantages and disadvantages of a methodological framework designed to analyze the poorly understood relationships between the ecosystem properties of large portions of land, and their capacities (stocks) to provide goods and services (flows). These capacities (stocks) are referred to as landscape functions. The core of our assessment is a set of expert- and literature-driven binary links, expressing whether specific land uses or other environmental properties have a supportive or neutral role for given landscape functions. The binary links were applied to the environmental properties of 581 administrative units of Europe with widely differing environmental conditions and this resulted in a spatially explicit landscape function assessment. To check under what circumstances the binary links are able to replace complex interrelations, we compared the landscape function maps with independently generated continent-wide assessments (maps of ecosystem services or environmental parameters/indicators). This rigorous testing revealed that for 9 out of 15 functions the straightforward binary links work satisfactorily and generate plausible geographical patterns. This conclusion holds primarily for production functions. The sensitivity of the nine landscape functions to changes in land use was assessed with four land use scenarios (IPCC SRES). It was found that most European regions maintain their capacity to provide the selected services under any of the four scenarios, although in some cases at other locations within the region. At the proposed continental scale, the selected input parameters are thus valid proxies which can be used to assess the mid-term potential of landscapes to provide goods and services. 相似文献
556.
Asish Roy 《International Journal of Green Energy》2018,15(2):80-95
Wind is one of the fastest growing renewable energy resources in the electric power system. Availability of wind energy is volatile in nature due to the stochastic behavior of wind speed and non-linear variation of the wind power curve of wind turbine generator. Because of this impression and uncertainty, the availability estimation of wind power has become a challenging issue. In this paper, Markov Fuzzy Reward technique has been proposed for finding out the reliability of wind farm by assessing the availability of wind power. According to this technique, availability of the wind power has been estimated considering wind farm and demand both as a multi-state system. In addition to the availability, different reliability indices such as the number of absolute failures, mean time to deficiency, and probability of failures of a wind farm have been assessed in a time horizon, which can provide useful information for the power system planner at wind farm installing stage. A comparison of this study reveals the efficacy of the proposed Markov Fuzzy Reward approach over the conventional Markov Reward approach. 相似文献
557.
Moe Chowdhury 《Waste management (New York, N.Y.)》2009,29(8):2240-2247
Effective waste reduction and recycling is predicated upon credible data on refuse generation and disposal. Despite improvements in the quality of data for municipal solid wastes (MSW) disposal, dependable generation and recycling statistics to support planning, regulation and administration are lacking. The available aggregates on national waste production from two sources do not conform to each other and fail to serve the requirements of local solid waste planning. As recycling estimates will be difficult to discern, the collection of generation data based on weighing waste samples at generator sites has been portrayed as the key for developing sustainable local databases. The coefficients developed from the databases for the various categories of residential, commercial, industrial and institutional wastes can be used as variables for waste generation models. 相似文献
558.
A comparative study evaluated the acid, alkali, and heat-treated polyethylene biodegradation efficiency of Pseudomonas aeruginosa AMB-CD-1. The polyethylene (PE) pieces were separately treated with heat (50°C), acid (1N HCl), and alkali (1N NaOH) and then washed with water before use. All the treated samples were analyzed through thermogravimetric analysis. In addition, weight and temperature changes during the decomposition reactions were also measured and determined. In these treatments, the PE films of heat-treated and acid-treated low-density polyethylene (LDPE) indicated more significant weight loss at 120°C (48.99% and 40.75%, respectively) as compared to their control or untreated PE and alkali-treated LDPE (21.84% and 24.68%, respectively). A biodegradation assay was then conducted with treated and untreated LDPE films with P. aeruginosa AMB-CD-1 strain. Fourier transform infrared spectroscopy analysis revealed that the heat or acid-pretreated samples with isolate AMB-CD-1 displayed peaks at 2922.84, 2923.97, and 1450.31, 874.22 cm−1 for C–H stretching deformation vibration, CH2 scissoring vibration, –CHO stretching, and strong alkyl structure, respectively. Furthermore, the new peaks with a significant difference at 2500–2000 cm−1 (O═C═O, O–H stretching vibration: carboxylic acid) and 1500–1000 cm−1 (–CHO and C═O stretching) were noticed in the infrared spectral range of LDPE degradation. Modifications in the functional group provided evidence that biodegradation had impacted the chemical structure of the LDPE film. Additionally, it was demonstrated that pretreating LDPE films with heat or acid could speed up their biodegradation. 相似文献
559.
Farhana Gul-E-Noor Mubarak A. Khan Sushanta Ghoshal Ruhul A. Khan Russel A. Mazid A. M. Sarwaruddin Chowdhury 《Journal of Polymers and the Environment》2010,18(3):224-230
Thin films of gelatin were prepared by casting. Then the films were photocured and the mechanical properties were studied.
The tensile strength of UV cured gelatin films showed about 10% enhancement than that of raw gelatin films. Minor amount of
urea (1–5%) was used as additive in aqueous gelatin solution and films were prepared using same technique. Four formulations
were prepared in methanol with 2-ethylhexyl acrylate in the presence of photoinitiator (darocur-1664). The films were soaked
in the prepared formulations and then cured under UV radiation at different intensities (5–25 passes). Percentage of urea,
monomer concentration, soaking time and radiation intensities were optimized with the extent of polymer loading, TS and elongation
at break of the photocured film. The films containing 2% urea, cured with 3% EHA for 3 min at 15th UV pass showed the highest
mechanical properties. A significant improvement of TS (31%) occurred when EHA (3%) was incorporated. 相似文献
560.
Jonn A. Foulk Wayne Y. Chao Danny E. Akin Roy B. Dodd Patricia A. Layton 《Journal of Polymers and the Environment》2006,14(1):15-25
Manufacturing composites with polymers and natural fibers has traditionally been performed using chopped fibers or a non-woven mat for reinforcement. Fibers from flax (Linum usitatissimum L.) are stiff and strong and can be processed into a yarn and then manufactured into a fabric for composite formation. Fabric directly impacts the composite because it contains various fiber types via fiber or yarn blending, fiber length is often longer due to requirements in yarn formation, and it controls the fiber alignment via weaving. Composites created with cotton and flax-containing commercial fabrics and recycled high-density polyethylene (HDPE) were evaluated for physical and mechanical properties. Flax fiber/recycled HDPE composites were easily prepared through compression molding using a textile preform. This method takes advantage of maintaining cotton and flax fiber lengths that are formed into a yarn (a continuous package of short fibers) and oriented in a bidirectional woven fabric. Fabrics were treated with maleic anhydride, silane, enzyme, or adding maleic anhydride grafted polyethylene (MAA-PE; MDEX 102-1, Exxelor® VA 1840) to promote interactions between polymer and fibers. Straight and strong flax fibers present problems because they are not bound as tightly within yarns producing weaker and less elastic yarns that contain larger diameter variations. As the blend percentage and mass of flax fibers increases the fabric strength, and elongation generally decrease in value. Compared to recycled HDPE, mechanical properties of composite materials (containing biodegradable and renewable resources) demonstrated significant increases in tensile strength (1.4–3.2 times stronger) and modulus of elasticity (1.4–2.3 times larger). Additional research is needed to improve composite binding characteristics by allowing the stronger flax fibers in fabric to carry the composites load. 相似文献