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731.
以鑫汇金矿的氰化尾渣为研究对象,利用工艺矿物学研究方法,分别进行光谱分析、物相分析和化学分析. 氰化尾渣中w(Pb)和w(Zn)较高,分别达到12.45%和14.00%. 方铅矿和闪锌矿为可回收的铅锌矿物,2种矿粒度主要分布于10~43 μm. 针对方铅矿、闪锌矿的浮选特点,对矿浆进行预处理,并利用新型浮选技术和药剂制度,以提高选矿生产技术指标. 其中铅锌混合精矿中w(Pb)和w(Zn)分别为24.41%和24.55%,锌精矿中w(Zn)为46.63%. 在选矿废水中加入氧化剂,可使其净化后循环利用,由此可节约新鲜水380 m3/d;尾矿可作为制酸原料和水泥原料. 相似文献
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733.
扬州市区大气环境污染特征分析及其防治对策 总被引:6,自引:1,他引:5
以扬州市区“八五"期间大气环境监测数据为基础,评价了大气环境质量的现状,分析了大气污染特征及其产生原因,揭示了污染变化规律,指出了市区大气环境存在的主要问题。最后,提出了市区大气污染防治对策。 相似文献
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736.
Xuying Ma Ian Longley Jennifer Salmond Jay Gao 《Frontiers of Environmental Science & Engineering》2020,14(3):44
737.
本文从MODIS数据的气溶胶光学厚度反演为理论出发,以河南省近期某一时段下的大气质量为研究对象,论证了反演手段与地面实测数据的契合性和大气遥感监测在大范围时空区域内的优越性和不可替代性;同时结合地面实测数据对河南省AOD空气质量监测做了研究分析,探讨了大气污染专项防治专项的绩效成果并对其影响因素做了进一步分析。在环境问题日益迫切和国民环保意识越发迫切的当下,大气遥感监测势必将会在环保领域发挥更大的作用。 相似文献
738.
Zehra Bozkurt 《Environmental Forensics》2018,19(1):1-13
The objective of this study was to determine the concentrations of inorganic ions present in particulate matter smaller than 10 µm (PM10), released into the environment by industrial, domestic and mobile sources in Duzce. To assess spatial variations, samples were collected from two sampling sites that had urban and suburban characteristics. Further, the process was carried out in two seasons to understand the seasonal variations. An ion chromatography device was used for analyzing the inorganic ion content in the collected samples. The highest levels of inorganic ion concentrations were measured at the urban sampling site during the winter campaign. Furthermore, the highest ion concentrations were measured for SO42? ion at both sampling sites and during both seasons, while the lowest concentrations were measured for Br?. Moreover, there were significant relationships between meteorological parameters and ion concentrations. A comparison of the cation and anion equivalence values using seasonal CE/AE (cation equivalence/anion equivalence) ratios showed that the aerosol matter had alkaline characteristics during both seasons. The mean value for the CE/AE ratios was 1.58 in winter and 2.06 in summer at the urban sampling site and 1.36 in winter and 1.52 in summer at the suburban sampling site. The interrelationships among the ions were determined by Pearson correlation analysis. Based on the correlation analyses, the ions emitted from common sources and those exposed to similar atmospheric conditions displayed strong correlations with each other. 相似文献
739.
Tomaz Langenbach Denise Mano Maize M. Campos Alessandra L.M.C. Cunha Tácio M.P. De Campos 《Journal of environmental science and health. Part. B》2017,52(12):843-849
Pesticide air pollution by spraying was evaluated under different temperature, humidity and wind climatic conditions in Brazil. Field experiments were performed with application towards the soil and in guava orchards, where spray dispersion was monitored by adding p-aminobenzoic acid (PABA), a fluorescent substance, as a tracer to the water contained in the spray tanks. Samples were collected with filter membranes (Whatman 180025), and the PABA was extracted from the filters by shaking with water in a Petri dish and measured in a spectrofluorometer. A spray aimed towards the soil with filters positioned on the ground and hung at different heights did not show different upward dispersion as observed when lateral pulverization was conducted. In this case, a tractor with a sprayer moved through a 3 m high and 6 m wide frame with filter membranes mounted at 60 cm intervals. Spray dispersion patterns were modified by guava leaf resistance. No influence of temperature and humidity was observed in this short-lived spraying process. Nevertheless, wind drift can occur during airborne dispersion and is an important pesticide pollution source which requires control. Droplets with PABA powered by assisted spraying upwards returned to the ground by gravity and, therefore, did not constitute a vertical source of atmospheric pollution. 相似文献
740.
This paper offers an analysis of the implementation performance of the EU Ambient Air Quality directive in the Netherlands. It provides a systematic evaluation of the implementation of a procedural provision – the obligation to design air quality policy. It draws on original data on air quality policy measures that have been collected in 13 medium-sized Dutch municipalities. The analysis of differences in the implementation performance was performed using a novel three-dimensional conceptual framework. The findings illustrate great differences in the implementation performance between the municipalities. The focused comparison allowed establishing very precisely where the implementation performance is poor or even lacking, and which municipalities take their EU implementation task more seriously than others. Most puzzling, environmental problem pressure turned out not to act as a sufficient trigger for municipalities to take far-reaching air quality measures. In contrast to previous research, a more nuanced picture is painted when it comes to the concepts of ‘compliance’, ‘non-compliance’ and ‘over-compliance’. A careful dissection of the implementation performance based on the aspects of the conceptual framework produces hands-on recommendations to municipalities seeking to improve their air quality policy. 相似文献