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371.
Institutional credibility and leadership: critical challenges for community-based natural resource governance in rural and remote Australia 总被引:1,自引:1,他引:0
Community-based natural resource management (CBNRM) institutions are challenged with finding common ground as a basis for
action among diverse resource users and stakeholders. Establishing and maintaining institutional credibility within their
regions, catchments, communities and among their membership is fundamental to overcoming the challenge. So too is applying
appropriate institutional and governance structures and appointing appropriate leaders. Drawing on triangulated case study
data collected over a 12-month period using multiple methods, this paper examines the influence of institutional credibility
and leadership on the functioning, decision-making and governance of two CBNRM institutions in Queensland, Australia. The
paper shows that stakeholders have very different expectations of what makes a CBNRM institution credible. Satisfying the
multiple expectations requires CBNRM institutions to incorporate diverse stakeholder representation, assert their legitimacy
and demonstrate accountability, transparency, fairness and justice. The paper also draws attention to the value and importance
of appointing inspirational leaders who focus on encouraging followers to pursue collective goals. Comparing the merits and
constraints of appointing average Joes versus community elites to the Boards of CBNRM institutions, the paper highlights the
urgent need for community-based natural resource governance and inspirational leadership education and training programs to
improve the availability and quality of CBNRM leadership in rural Australia. Since combining credible CBNRM institutions with
inspirational leaders does not necessarily equate to sustainable on-ground NRM outcomes, it is critical that the education
and training programs emphasise the importance of monitoring and evaluating the improvements in decision-making processes
and in decision outcomes. 相似文献
372.
A 2D physical model of the human head was used to investigate how the irregular skull base structure affects brain kinematics during sagittal plane head dynamics. The model consisted of a rigid skull vessel with interchangeable skull base structures. One version of the model used a skull base mimicking the irregular geometry of the human. A second version used a skull base structure approximating the anterior and middle fossae as a flat surface. Silicone gel simulated the brain and was separated from the vessel by a paraffin layer which provided a slip condition at the interface between the gel and vessel. The model was exposed to 7600 rad/s2 peak rotational acceleration with 6 ms pulse duration and 5° forced rotation. After 90° free rotation, the model was decelerated during 30 ms. Five repeated tests were conducted with each version. Rigid body displacement, shear strain and principal strains were determined from high-speed video recorded trajectories of grid markers located at different positions in the surrogate brain. The humanlike skull base reduced peak displacements of the inferior surfaces of the temporal and frontal lobes up to 87% and 48%, respectively. Up to 48% and 36% higher peak strains were obtained in the frontal and superior regions of the surrogate brain in the version containing the humanlike skull base. In contrast, the humanlike skull base decreased peak strain up to 28% in the central region of the surrogate brain. The results indicate that the irregular skull base offers natural protection of nerves and vessels passing through fissures and foramina in the cranial floor but also that it affects kinematics in different regions throughout the cerebrum. Implications of these results are discussed with respect to brain injury and modeling of head impact. 相似文献
373.
Leachate derived from unlined coal ash disposal facilities is a potential anthropogenic source of arsenic to the environment. To establish a theoretical framework for predicting attenuation of arsenic by soils subject to ash landfill leachate, which is typically enriched in calcium and sulfate, the adsorption of As(V) and As(III) was characterized from 1 mM CaSO4 for 18 soils obtained down-gradient from three ash landfill sites and representing a wide range in soil properties. As(V) consistently exhibited an order of magnitude greater adsorption than As(III). As(V) adsorption was best described by coupling pH with 15 s DCB-Fe (R2 = 0.851, = 0.001), although pH coupled to clay, DCB-Fe, or DCB-Al also generated strong correlations. For As(III), pH coupled to Ox–Fe (R2 = 0.725, = 0.001) or Ox–Fe/Al (R2 = 0.771, = 0.001) provided the best predictive relationships. Ca2+ induced increases in As(V) adsorption whereas sulfate suppressed both As(V) and As(III) adsorption. Attenuation of arsenic from ash leachate agreed well with adsorption measured from 1 mM CaSO4 suggesting that the use of 1 mM CaSO4 in laboratory adsorption tests is a reasonable approach for estimating arsenic behavior in soils surrounding ash landfills. We also showed that the impact of leachate-induced changes in soil pH over time may not be significant for As(V) adsorption at pH < 7; however, As(III) adsorption may be impacted over a wider pH range especially if phyllosilicate clays contribute significantly to adsorption. The benefits and limitations of predicting arsenic mobility using linearized adsorption coefficients estimated from nonlinear adsorption isotherms or from the relationships generated in this study are also discussed. 相似文献
374.
Investigation on the adsorption capability of egg shell membrane towards model textile dyes 总被引:1,自引:0,他引:1
Adsorption isotherms of Direct Red 80 (DR80) and Acid Blue 25 (AB25) on the egg shell membrane (ESM) were performed at 20 ± 1 °C. Physical characteristics of ESM such as surface area and presence of functional groups were verified. The Fourier transform infra-red (FTIR) spectra proved the presence of fuctional groups such as hydroxyl, amine and carbonyl groups in ESM. The surface area of ESM was found to be 2.2098 m2/g. The effects of operational parameters such as initial dye concentration, pH0, contact time, particle size and ESM doses were studied. The Langmuir, Freundlich, BET, Redlich-Peterson and Temkin adsorption models were applied to describe the equilibrium isotherms. The pseudo-first-order and pseudo-second-order kinetics models were examined to evaluate the kinetics data at different pH0 values (2–12) and the rate constants were calculated. Maximum desorption of 81.8% was achieved for both dyes in aqueous solution at pH0 12. Also scanning electron micrographs (SEM) of the treated and untreated adsorbent were performed. Results indicate that ESM could be employed as a natural and Eco-Friendly adsorbent material for the removal of trace organics in solutions. 相似文献
375.
The impact of seasonal variations in DOC arising from a moorland peat catchment on coagulation with iron and aluminium salts 总被引:6,自引:0,他引:6
Sharp EL Parsons SA Jefferson B 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):436-443
Natural organic matter (NOM) is one of the main sources of environmental pollution to drinking water supplies in much of the UK and the US. Whilst traditional treatment with trivalent coagulants has proven a successful strategy in the past, operational problems are now being reported during periods of elevated organic levels in the water. Characterisation of the pollutants in terms of polarity, molecular weight and charge, provides a method to understand the impact of the observed temporal and spatial variations in terms of a mechanistic parameter relevant to the treatment processes. Results from this study demonstrate that it is not simply the increased organic concentration, but also the change in NOM composition and character, which influences the impact on the treatment processes. Consequently, monitoring of these parameters provides an insight into how to manage the impact caused by environmental changes to the catchments. 相似文献
376.
William Ascher 《Sustainability Science》2006,1(1):15-22
Given progress in policies for pursuing sustainable development, promoting commitment to thinking and acting more far-sightedly has become the primary strategic challenge. In the face of impatience, selfishness, uncertainty, analytical limitations, and vulnerability, strategies for promoting far-sightedness can be identified by assessing how these obstacles can be overcome. Strategies for creating or rescheduling tangible and deference rewards, realigning performance evaluations, implementing cognitive exercises, framing communications, altering decision-making processes, using self-restraint devices both to resist temptation and to enhance credibility, altering institutions to empower the patient, and stabilizing living conditions are the major categories for identifying and assessing the many strategies which arise out of both ordinary and constitutive policy initiatives.
相似文献
William AscherEmail: Phone: +1-909-6073071Fax: +1-909-6218419 |
377.
Regulated rivers in the United States are required to support human water uses while preserving aquatic ecosystems. However,
the effectiveness of hydropower license requirements nationwide has not been demonstrated. One requirement that has become
more common is “run-of-river” (ROR) operation, which restores a natural flow regime. It is widely believed that ROR requirements
(1) are mandated to protect aquatic biota, (2) decrease hydropower generation per unit flow, and (3) decrease energy revenue.
We tested these three assumptions by reviewing hydropower projects with license-mandated changes from peaking to ROR operation.
We found that ROR operation was often prescribed in states with strong water-quality certification requirements and migratory
fish species. Although benefits to aquatic resources were frequently cited, changes were often motivated by other considerations.
After controlling for climate, the overall change in annual generation efficiency across projects because of the change in
operation was not significant. However, significant decreases were detected at one quarter of individual hydropower projects.
As expected, we observed a decrease in flow during peak demand at 7 of 10 projects. At the remaining projects, diurnal fluctuations
actually increased because of operation of upstream storage projects. The economic implications of these results, including
both producer costs and ecologic benefits, are discussed. We conclude that regional-scale studies of hydropower regulation,
such as this one, are long overdue. Public dissemination of flow data, license provisions, and monitoring data by way of on-line
access would facilitate regional policy analysis while increasing regulatory transparency and providing feedback to decision
makers. 相似文献
378.
Jérôme Labille Jinghuan Feng Daniel Borschneck Magali Sammut Mélanie Auffan Jérôme Rose Jean-Yves Bottero 《Environmental pollution (Barking, Essex : 1987)》2010,158(12):3482-91
Aging in water of a TiO2-based nanocomposite used in sunscreen cosmetics has been studied as a function of light and time. It consisted initially in a TiO2 core, coated with Al(OH)3 and polydimethylsiloxane (PDMS) layers. Size measurement, coating alteration, and surface charge were followed by laser diffraction, TEM/EDS, ICP-AES and electrophoretic mobility measurement.The nanocomposite rapidly underwent progressive dispersion in the aqueous phase, enabled by the dissolution of the PDMS layer. A stable suspension of colloidal byproducts from 50 to 700 nm in size was formed. Their positively charged Al(OH)3 surface was evidenced with an isoelectric point around 7-8, controlling the dispersion stability. The critical coagulation concentrations measured with NaCl and CaCl2 was 2 × 10−2 and 8 × 10−3 M respectively. The presence of natural organic matter affected the colloidal stability according to the NOM/byproduct ratio. A 2 wt% ratio favored bridging flocculation, whereas a 20 wt% ratio induced sterical stabilization. 相似文献
379.
People matter: The importance of social capital in the co-management of natural resources 总被引:2,自引:0,他引:2
Co‐management involves the shared administration of natural resources by two or more parties. This study examines the role of social capital in the process of developing co‐management in three river corridors in Canada. Qualitative analysis reveals that social capital acts as a catalyst helping groups to progress through the stages of the co‐management process. Forms of social capital (bridging and bonding) are identified that advance and/or inhibit the development of co‐management. The article reaffirms the need to expand the institutional basis for natural resource management and provides empirical evidence that social capital plays a fundamental role in developing co‐management. In conclusion, the article suggests that resource agencies need to recognize the value of social capital and the necessity for government representatives to be informed of and practiced in these skills, if they are to engage meaningfully with the civilian population. 相似文献
380.
本文选取内蒙古锡林郭勒盟太仆寺旗温带半干旱典型草原及其邻近不同开垦年限的农田(5年,10年,50年)为研究对象,利用静态暗箱法对土壤CH4的吸收通量进行了野外观测试验。结果表明:天然草地转化为农田后,土壤吸收CH4的能力增强,随农垦年限的增加,土壤对CH4的吸收能力呈现逐渐降低趋势,依次为F5〉FIO〉F50〉G。 相似文献