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991.
Atmospheric mercury at mediterranean coastal stations 总被引:2,自引:0,他引:2
Ingvar Wängberg John Munthe David Amouroux Maria E. Andersson Vesna Fajon Romano Ferrara Katarina Gårdfeldt Milena Horvat Yaacov Mamane Ety Melamed Mathilde Monperrus Nives Ogrinc Osnat Yossef Nicola Pirrone Jonas Sommar Francesca Sprovieri 《Environmental Fluid Mechanics》2008,8(2):101-116
Mercury in air has been measured at five coastal Mediterranean sites, involving measurements in Spain, France, Italy, Slovenia and
Israel. Four two-weeks long measurements campaigns were performed at the five sites. The measurements were carried out during
autumn 2003 and winter, spring and summer 2004. Total gaseous mercury/elemental gaseous mercury, particulate mercury and divalent
gaseous mercury were measured in parallel at the five sites. The activities constituted a subtask of the EU funded MERCYMS
research project, which also included Mediterranean Sea cruises where both mercury in air and water were measured. The result
from an evaluation of all the coastal air data is presented. Mercury concentrations from the different sites are compared
with similar data obtained in northern Europe and elsewhere. The result shows that the background concentration of mercury
in Mediterranean coastal air is lower than earlier anticipated. Background concentrations of TGM, RGM and TPM corresponded
to 1.75–1.80 ng m−3, 1–13 and 3–23 pg m−3, respectively. The measurements also showed that the mercury concentration occasionally can be very high in some areas due
to local anthropogenic emissions. It is proposed that diurnal variation in RGM concentrations observed during situation with
nocturnal inversion merely is an effect of meteorology rather than due to local photochemistry. 相似文献
992.
Eduardo Chandia Fabienne Sallaberry Marcelino Sánchez 《International Journal of Sustainable Engineering》2016,9(4):240-250
The mining industry represents more than half of Chile’s foreign exchange earnings and its increasing expansion will demand a continuous development of its energy supplies. Mostly, all the mines in Chile are located in the desert regions, having a large surface with one of the highest solar radiations levels and clearest skies in the world. Covering the mining industry’s energy demand with solar energy is thus an obvious and promising approach. In this paper, the implementation of solar thermal heating is studied in every mining process and the solar thermal electricity generation for the entire mine demand is considered as well. The work concludes that the installation of flat plate collectors to heat water for mine processes, especially for electrowinning, is strongly recommended. Additionally, the installation of solar thermal power plants can satisfy the mining electricity demand. 相似文献
993.
燃煤电厂排放总气态汞连续自动监测技术的选择 总被引:1,自引:0,他引:1
介绍了汞连续排放监测系统和汞吸附管采样系统的主要特点,比较了不同仪器的测定原理、样品处理技术、检出限和测定汞的形态,报道了美国环境保护署认证中心关于两个系统的认证结果.建议将汞连续排放监测系统与汞吸附管监测系统两种技术联合用于我国燃煤电厂排放总气态汞的自动监测. 相似文献
994.
压煤村庄搬迁对农业生产的影响——以兖州市为例 总被引:1,自引:0,他引:1
我国的煤炭资源开采大部分都是采取井下开采的方式,该种开采方式在进行过程中容易引起覆岩层的原始平衡状态遭受破坏,同时伴随冒落、断裂或者弯曲等移动变形的情况出现,并最终涉及地表。到目前为止,由采矿引起的地面塌陷和地表开裂,已经导致了大量建筑物被破坏,给农民的生产生活带来了极大的不便,对农业生产的发展造成了极大的阻扰,减少了耕地,形成了社会的不稳定因素,严重影响地区的社会的发展与稳定。压煤村庄搬迁能改善矿区居民的生活环境和基础设施建设,加快小城镇建设和城乡一体化发展的进程,但是由于村庄搬迁引起的耕作半径增加,改变了从居住区到田地的距离,引起机械化程度、耕种方式和农业劳动力需求等变化,从而将在一定程度上影响本地区的社会稳定性,也会增加整个社会的就业压力。山东省是重要的产煤发展基地,村庄搬迁后远离耕地,为农民的往返与出入带来了不便。本文以兖州市已搬迁的八个村庄为研究对象,采取调查问卷的形式进行了实地调研,并将调查后的数据进行了分类统计与回归分析,运用SPSS软件进行Logit模型回归分析,最终确定主要生活来源和田间道路修建两个因子与农民从事农业生产的意愿存在密切的相关性,交通工具的变更与大型机械的配备对其也有较大的影响作用,研究结果可为该政府相关部门制定村庄搬迁和农业生产有着重要的理论指导意义。 相似文献
995.
调查了神东矿区23个单位附属绿地的绿化结构,测定并评价了绿地的各种功能效益和蒸腾耗水量,最后选择绿地持续稳定、功能效益、蒸腾耗水量、整体美景度4个方面10个指标,用主成分分析法综合评价了不同绿地配置模式的优劣顺序,筛选出较好的配置模式。评价分析表明:上湾小学总体表现最好,神东煤矿职工生活小区总体表现普遍较差;绿量是决定城市绿地功能效益的关键因素,城市绿化不仅要增加绿化覆盖率,还要注重提高单位面积绿地绿量;乔木树种不仅绿量和发挥的功能效益最大,蒸腾耗水量也很大,因此,干旱半干旱地区城市单位附属绿地在提高节水乔木树种(如新疆杨Populus alba var.pyramidalis)比例的同时,还应注重配置花灌木树种(如玫瑰Rosa rugosa、紫丁香Syringa oblata),并适当地用自然杂草代替人工草坪覆盖地表,以适应干旱地区水分短缺的需求。 相似文献
996.
Assuring the quality, consistency and accuracy of safety data repositories is essential in safety-critical systems. In many systems, however, significant effort is required to identify, address, clean and repair data errors and inconsistencies, and to integrate safety data sets and repositories, particularly for risk analyses. Although some self healing and self repairing capabilities leveraging machine learning and predictive analyses have been employed to identify anomalies and monitor quality in structured safety-critical data sets, little attention has been focused on addressing shortcomings in heterogeneous—structured and unstructured—safety data sets, the focus of this work. The text mining and classification analysis employed in this research indicates that machine learning techniques can be employed to improve the accuracy and robustness of large-scale structured and unstructured database repositories, and to improve the effectiveness and efficiency of safety data repository maintenance. Hybrid machine learning approaches, leveraging machine learning, text mining and natural language processing, offer additional promise in future work. 相似文献
997.
Adequate temporal trend analysis of mercury (Hg) in freshwater ecosystems is critical to evaluate if actions from the human society have affected Hg concentrations ([Hg]) in fresh water biota. This study examined temporal change in [Hg] in Northern pike (Esox lucius L.) in Swedish freshwater lakes between 1994 and 2006. To achieve this were lake-specific, multiple-linear-regression models used to estimate pike [Hg], including indicator variables representing time and fish weight and their interactions. This approach permitted estimation of the direction and magnitude of temporal changes in 25 lakes selected from the Swedish national database on Hg in freshwater biota. A significant increase was found in 36% of the studied lakes with an average increase in pike [Hg] of 3.7 ± 6.7% per year that was found to be positively correlated with total organic carbon. For lakes with a significant temporal change the dataset was based on a mean of 30 fish, while for lakes with no temporal change it was based on a mean of 13 fish. 相似文献
998.
999.
Gavin M. Mudd James Patterson 《Environmental pollution (Barking, Essex : 1987)》2010,158(5):1252-1260
The former Rum Jungle uranium-copper project, Australia, is an internationally important case study on environmental pollution from and rehabilitation of mining. The Rum Jungle mining project is briefly reviewed, followed by a critical evaluation of monitoring data and pollution loads prior to and after rehabilitation - leading to the conclusion that rehabilitation has clearly failed the test of time after just two decades. The most critical findings are the need to understand pollution cycles holistically, and designing monitoring regimes to match, explicit inclusion of radiological criteria (lacking in original planning), and finally the need to set targets based on environmental criteria. Two examples include polluted groundwater which was excluded from rehabilitation and the poor design, construction and/or performance of engineered soil covers - both leading to increasing acid drainage impacts on the Finniss River. The critical review therefore presents a valuable case study of the environmental performance of uranium mine site rehabilitation. 相似文献
1000.
Roberto Terzano Anna Santoro Bart Vekemans Koen Janssens Melissa A. Denecke Pacifico Ruggiero 《Environmental pollution (Barking, Essex : 1987)》2010,158(8):2702-2709
Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg−1. Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as μ-XRF, μ-XRD and μ-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 μm. The main Hg-species found in the soil samples were metacinnabar (β-HgS), cinnabar (α-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 μm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. 相似文献