全文获取类型
收费全文 | 1309篇 |
免费 | 930篇 |
国内免费 | 179篇 |
专业分类
安全科学 | 111篇 |
废物处理 | 98篇 |
环保管理 | 85篇 |
综合类 | 1259篇 |
基础理论 | 337篇 |
污染及防治 | 474篇 |
评价与监测 | 44篇 |
社会与环境 | 5篇 |
灾害及防治 | 5篇 |
出版年
2025年 | 11篇 |
2024年 | 53篇 |
2023年 | 72篇 |
2022年 | 115篇 |
2021年 | 103篇 |
2020年 | 93篇 |
2019年 | 89篇 |
2018年 | 95篇 |
2017年 | 107篇 |
2016年 | 97篇 |
2015年 | 118篇 |
2014年 | 156篇 |
2013年 | 139篇 |
2012年 | 141篇 |
2011年 | 126篇 |
2010年 | 109篇 |
2009年 | 118篇 |
2008年 | 72篇 |
2007年 | 133篇 |
2006年 | 97篇 |
2005年 | 55篇 |
2004年 | 47篇 |
2003年 | 59篇 |
2002年 | 42篇 |
2001年 | 27篇 |
2000年 | 24篇 |
1999年 | 20篇 |
1998年 | 20篇 |
1997年 | 16篇 |
1996年 | 22篇 |
1995年 | 7篇 |
1994年 | 12篇 |
1993年 | 7篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有2418条查询结果,搜索用时 15 毫秒
1.
摘要以镁盐、铝盐、纯碱和烧碱为原料制备了一种多孔镁铝复合氧化物(P—Mg3.1AlO4.6),其比表面积、平均孔径和总孔容分别为206.3m2/g、8.961nm和0.4208cm3/g。研究了这种多孑L材料对水溶液中cr(VI)的吸附性能,在25~45qC时,静态吸附量为82.32~141.7mg/g;当初始浓度100mg/L、流速5mL/min、床层高度10cm和pH=6时,半穿透时间、半穿透吸附量和饱和吸附量分别为406rain、49.28ing/g和51.30Ing/g;拟合参数及误差分析表明,cr(Ⅵ)在P—M敬。AIO4.6上的静态吸附过程符合Freundlich等温方程式和伪二级动力学方程,Yoon·Nelson模型能很好地预测cr(Ⅵ)在P—Mg3.1A104.6上的动态穿透曲线。 相似文献
2.
Lanqian Gong Huan Yang Abdoulkader Ibro Douka Ya Yan Bao Yu Xia 《Advanced Sustainable Systems》2021,5(1)
The oxygen evolution reaction (OER) is significant for energy conversion and storage technologies. However, efficient electrocatalysts are required to overcome its sluggish kinetics. Recently, NiFe‐based composites have shown to be promising electrocatalysts for alkaline OER, and numerous efforts have been invested in the development of low‐cost and advanced NiFe‐based nanostructures. In this mini review, the latest developments in NiFe‐based electrocatalysts are summarized and discussed. Following the introduction of the OER mechanism, different NiFe electrocatalysts in alloys, (hydr)oxides, and other derived compounds are successively introduced. Moreover, the synthesis methods of typical layered NiFe hydroxide structures are also introduced. Finally, recent progress is summarized and some perspectives are provided for addressing future challenges for NiFe‐based electrocatalysts. It is believed that this review may provide useful reference for the future design and preparation of NiFe compounds for the alkaline OER and beyond. 相似文献
3.
《环境科学学报(英文版)》2023,130(8):65-74
Heterogeneous reaction of NO2 with mineral dust aerosol may play important roles in troposphere chemistry, and has been investigated by a number of laboratory studies. However, the influence of mineralogy on this reaction has not been well understood, and its impact on aerosol hygroscopicity is not yet clear. This work investigated heterogeneous reactions of NO2 (∼10 ppmv) with K-feldspar, illite, kaolinite, montmorillonite and Arizona Test Dust (ATD) at room temperature as a function of relative humidity (<1% to 80%) and reaction time (up to 24 hr). Heterogeneous reactivity towards NO2 was low for illite, kaolinite, montmorillonite and ATD, and uptake coefficients of NO2, γ(NO2), were determined to be around or smaller than 1×10−8; K-feldspar exhibited higher reactivity towards NO2, and CaCO3 is most reactive among the nine mineral dust samples considered in this and previous work. After heterogeneous reaction with NO2 for 24 hr, increase in hygroscopicity was nearly insignificant for illite, kaolinite and montmorillonite, and small but significant for K-feldspar; in addition, large increase in hygroscopicity was observed for ATD, although the increase in hygroscopicity was still smaller than CaCO3. 相似文献
4.
在单一改良措施难以实现预期的盐碱地修复效果时,综合运用多种修复策略逐渐成为盐碱地改良的关键方向。该研究构建了Fe-耐盐功能菌群联合修复系统,结合土壤培养实验与16S rRNA基因高通量测序技术,系统研究了该联合系统对盐碱土理化性质的改善效果及其对植物生长的促进作用,探讨了微生物群落多样性、组成和功能在该修复系统中的响应特征。结果表明,Fe-耐盐功能菌群联用对土壤pH和含盐量改良效果显著。其中,5%Fe与耐盐功能菌联用修复效果最佳,可将土壤pH降低0.18、含盐量减少37.5%,使中度盐化、轻度碱化的土壤改良为轻度盐化、无碱化状态,并显著提升土壤全氮含量35.3%(P<0.05)。此外,该系统通过增强植物体内超氧化物歧化酶和脯氨酸的产生,有效缓解了盐胁迫带来的损伤,显著促进了植物的生长。改良措施显著改变了土壤理化性质,并对土壤微生物群落结构产生了较大影响,改良后土壤优势菌门为变形菌门(56.84%~75.48%)、拟杆菌门(19.31%~62.47%)、厚壁菌门(6.78%~8.85%)、放线菌门(2.80%~3.97%)、脱硫杆菌门(1.47%~3.08%)和盐厌氧菌门(0.88%~0.13%)。在属水平,Fe-耐盐功能菌群联用对污泥螺菌属、假单胞菌属、海杆菌属等产生驯化、富集作用,优化了盐碱地的作物生长环境。本研究不仅为提升盐碱地农作物产量提供了有效途径,还为发展可持续农业提供了重要的理论依据和数据支持。 相似文献
5.
Patricia M. Dooris Dean F. Martin 《Journal of the American Water Resources Association》1978,14(5):1088-1093
ABSTRACT: Iron, added as (Fe-EDTA)-, was found stimulatory to V. spiralis at a concentration of 0.05 ppm. (Fe-EDTA)- had no effect upon growth of V. neotropicalis as measured by changes in dissolved oxygen and dry weight. Results are compared with those derived from similar studies with Hydrilla verticillata and Egeria densa. The implications of lake drawdown and aeration are discussed. 相似文献
6.
7.
Road ambient air pollution status along Dhanbad – Jharia road isstudied and presented in this article. The selection of this areais made considering the importance of the road in Dhanbad district and the nature of activities taking place along the road, which reflect that the portion of road upto Dhansar can be considered as having commercial areas on both sides and that from Dhansar to Jharia as having industrial areas on both sides.For the assessment of the ambient air quality along the road monitoring is done at the following five locations: Indian Schoolof Mines (ISM), main gate; Bankmore; Dhansar police check post; Dhansar opencast project agent office and a residential house beside the Rajapur opencast project. The location of ISM, maingate is specially chosen as this represents a commercial shoppingcomplexes and the situation can be compared with that at Bankmore. Monitoring of ambient air quality is done following thestandard procedure prescribed in IS: 5182. In addition the concentration of lead, zinc, copper, iron, manganese, cadmium metals in SPM is also monitored. The ambient air quality is monitored in the months of September and November 1999, respectively, to represent monsoon and winter seasons. The SPM concentration observed at all the five locations in the winterseason is more than the permissible limits for commercial andindustrial areas. However, in the monsoon season, the SPM concentration is higher than the permissible limit at the twocommercial locations, i.e., ISM gate and Bankmore, while it isless than the prescribed limit for industrial areas at the remaining three locations. At the ISM gate and Bankmore the SPM generation is mainly by vehicular traffic while at other three locations it was in addition due to mining and other activities. 相似文献
8.
采用共混热解法制备系列Ce-Sn-W-Ox复合氧化物,用于NH3选择性催化还原NO。通过正交实验优化Ce-Sn-W-Ox配方,采用环境扫描电镜(ESEM)、X-射线衍射仪(XRD)等表征分析催化剂的微观形貌和固相结构,确立Ce-Sn-W-Ox最佳配比及结构形貌。结果表明,以粒度为5~8 mm的堇青石瓷片担载分散Ce-Sn-W-Ox,进行NH3-SCR脱除NO,当Ce/Sn/W元素摩尔比为1:0.8:0.6时,CeSn0.8W0.6Ox/堇青石NH3-SCR脱除NO效果最好。当空速为7 200 h-1,催化剂在252~426℃内脱除NO效率均大于94%。重点考察了反应空速(GHSV)、水蒸气(H2O)、SO2等对CeSn0.8W0.6Ox/堇青石NH3-SCR脱除NO活性的影响。研究表明,空速低于10 000 h-1时,催化剂脱硝活性受空速影响小;单独通入5%H2O对催化剂脱硝活性基本没有影响;单独通入429 mg/m3 SO2导致催化剂活性略有降低;同时通入429 mg/m3 SO2和5%H2O,催化剂脱硝活性下降至85.33%,除去SO2和H2O后,催化剂活性又能明显回升。 相似文献
9.
采用玉米芯为碳源,聚乙烯醇(PVA)为包埋载体,饱和硼酸(H3BO3)为交联剂,研究了硫酸盐还原菌污泥(SRBS)、铁屑、麦饭石共固处理合成煤矿酸性废水的最优配比与机理,并分析了固定化过程中小球稳定性及活性的变化规律。实验结果表明,SRBS投加量是影响处理效果的最显著因子,当投加30%SRBS、2%铁屑、3%麦饭石时SO42-、Mn2+去除率分别为94.13%和84.39%,溶液pH为7.03,未检测出Fe2+;随着交联时间的延长,小球膨胀率及SO42-还原率分别呈线性与指数下降,从保持小球稳定性与活性角度考虑,可将交联时间设定为4~8 h;该法可为市政污泥的处置以及生物法处理煤矿酸性废水的工程应用提供技术参考。 相似文献
10.
对含氨氮(NH3-N)的微污染原水,采用自制氧化铁改性石英砂(iron oxide coated sand,IOCS)滤料强化过滤与生物预处理技术联合,进行强化处理与吸附效果研究.结果表明,采用强化挂膜法,生物预处理反应器的生物膜成熟期约为7 d,其对氨氮的去除率为60%~70%,但反应器中存在亚硝酸盐氮积累的现象.IOCS与生物预处理技术联合,对NH3-N的平均去除率为84.67%,出水NH3-N浓度均低于0.5 mg/L,NO2--N含量趋于0;而普通石英砂(RQS)在同等条件下,对氨氮的去除效果不稳定,平均去除率为74.31%,出水NH3-N平均浓度未达标,对NO2--N平均去除率仅有33.29%.在4 m/h滤速工况下,与生物预处理技术联合,IOCS和RQS对NH3-N最高去除率分别为94.3%和82.72%.IOCS与RQS的表面形态结构存在明显差异:前者的表面结构更加复杂多孔,比表面积大,有利于生物牢固附着;后者表面较光滑,比表面积小,挂膜后生物易脱落. 相似文献