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831.
832.
833.
以新疆天山水泥股份有限公司一分厂1水泥磨除尘系统技术改造为实例,阐述了获1993年国家环保最佳实用技术推广的LCPM型高压离线侧喷脉冲袋除尘器在水泥磨系统的应用及产生的效果。 相似文献
834.
Liu J Yu H Song H Qiu J Sun F Li P Yang S 《Journal of environmental monitoring : JEM》2008,10(8):975-978
A novel, simple and sensitive liquid chromatography-hydride generation online coupled with atomic fluorescence spectrometry (LC-HG-AFS) method was developed for simultaneous determination of p-arsanilic acid (p-ASA) and roxarsone in feed. 20% Methanol aqueous was used as extraction reagent, after preprocessing samples by ultrasonic oscillation, then injected into the chromatography Waters symmetry shield RP18 analytical column (150mm x 4.6mm, 5 microm), finally detected by an atomic fluorescence spectrometer. The calibration curves of analyses were linear over a range of concentrations (0.2-4mg L-1 and the correlation coefficients were higher than 0.9990. The limits of detection were 0.2 mg L-1. The method has been validated by linearity, precision and recovery. p-ASA and roxarsone in feed can be successfully and simultaneously determined using the developed method without a tedious pretreatment procedure. 相似文献
835.
836.
内蒙古作为我国北方重要的生态屏障,多年来大力保护草原生态,已经基本建立了良好的生态系统。然而,内蒙古同时承担着清洁能源输出基地的职能,锡盟煤电外送基地将在2020年建成。届时,集中的开发必然导致锡盟草原的生态问题,因此亟需针对特定地区开展生态补偿问题,本文通过制度及政策分析,在排污权交易角度,提出一条解决生态补偿资金问题的新途径。并进行了制度模型的优势分析。 相似文献
837.
Emergy Assessment of a Wheat-Maize Rotation System with Different Water Assignments in the North China Plain 总被引:1,自引:0,他引:1
Sustainable water use is seriously compromised in the North China Plain (NCP) due to the huge water requirements of agriculture,
the largest use of water resources. An integrated approach which combines the ecosystem model with emergy analysis is presented
to determine the optimum quantity of irrigation for sustainable development in irrigated cropping systems. Since the traditional
emergy method pays little attention to the dynamic interaction among components of the ecological system and dynamic emergy
accounting is in its infancy, it is hard to evaluate the cropping system in hypothetical situations or in response to specific
changes. In order to solve this problem, an ecosystem model (Vegetation Interface Processes (VIP) model) is introduced for
emergy analysis to describe the production processes. Some raw data, collected by investigating or observing in conventional
emergy analysis, may be calculated by the VIP model in the new approach. To demonstrate the advantage of this new approach,
we use it to assess the wheat-maize rotation cropping system at different irrigation levels and derive the optimum quantity
of irrigation according to the index of ecosystem sustainable development in NCP. The results show, the optimum quantity of
irrigation in this region should be 240–330 mm per year in the wheat system and no irrigation in the maize system, because
with this quantity of irrigation the rotation crop system reveals: best efficiency in energy transformation (transformity = 6.05E + 4 sej/J);
highest sustainability (renewability = 25%); lowest environmental impact (environmental loading ratio = 3.5) and the greatest
sustainability index (Emergy Sustainability Index = 0.47) compared with the system in other irrigation amounts. This study
demonstrates that application of the new approach is broader than the conventional emergy analysis and the new approach is
helpful in optimizing resources allocation, resource-savings and maintaining agricultural sustainability. 相似文献
838.
839.
Zeyuan Qiu 《Journal of the American Water Resources Association》2010,46(5):944-956
Qiu, Zeyuan, 2010. Prioritizing Agricultural Lands for Conservation Buffer Placement Using Multiple Criteria. Journal of the American Water Resources Association (JAWRA) 1-13. DOI: 10.1111/j.1752-1688.2010.00466.x Abstract: Although conservation buffers are multifunctional, the current conservation buffer planning strategies tend to use a single criterion, most frequently a hydrological or soil condition indicator, to guide conservation buffer placement. This study presents a watershed planning approach that prioritizes agricultural lands for conservation buffers based on multiple selection criteria and applies the approach to Raritan Basin in central New Jersey. The multiple selection criteria include soil erodibility, hydrological sensitivity, wildlife habitat, and impervious surface rate. These criteria capture the conservation buffers’ benefits in reducing soil erosion, controlling runoff generation, enhancing wildlife habitat, and mitigating stormwater impacts, respectively. An expert panel was used to identify and define the section criteria, review the measured values of those criteria, and develop the classification scales that assign the class score to each criterion. The prioritization is based on the summation of the criteria class scores. About one-third of agricultural lands are prioritized for conservation buffers in Raritan Basin. The total program cost of converting those prioritized agricultural lands to conservation buffers in Raritan Basin is estimated to be between $54.8 and 102.9 million depending on the composition of installed conservation buffer practices. 相似文献
840.
洪湖是湖北省最大的湖泊,具有调蓄、灌溉、供水、渔业、物种保护、航运、旅游等多种功能,是长江中下游典型的大型浅水型湖泊。传统的设点监测费力、费时,随着遥感技术和手段的进步,遥感反演洪湖叶绿素a浓度成为技术上可能。利用2005年至2010年6年监测数据与同期MODIS数据进行统计分析,研究业务上进行洪湖叶绿素a含量反演的可能性,结果表明:当叶绿素a含量比较高时,它成为影响湖中NDVI指数的主要因素,当浓度较低时,它与NDVI指数相关性差,表明它不是主要要素;通过分析不同时段两者统计关系结果为:12~2月因藻类浓度比较小,叶绿素a浓度低,加上其它要素干扰湖中NDVI指数,监测数据与同期MODIS数据中NDVI指数相关性比较低(也是极显著相关),其它时间都有较好的相关性(相关系数都高于085),研究表明:运用MODIS数据中的NDVI指数能准确监测洪湖叶绿素a含量。并提出相应的业务处理流程与方法 相似文献