全文获取类型
收费全文 | 75篇 |
免费 | 4篇 |
国内免费 | 36篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 5篇 |
环保管理 | 6篇 |
综合类 | 42篇 |
基础理论 | 16篇 |
污染及防治 | 24篇 |
评价与监测 | 3篇 |
社会与环境 | 9篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 1篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 6篇 |
2012年 | 6篇 |
2011年 | 8篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 4篇 |
2007年 | 9篇 |
2006年 | 5篇 |
2005年 | 6篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1992年 | 2篇 |
排序方式: 共有115条查询结果,搜索用时 15 毫秒
11.
利用脱硫废碱液对酸化后的含铬废水进行处理,研究了废水初始pH、脱硫废碱液加入量和静置时间等对Cr(Ⅵ)转化率的影响.实验结果表明,在废水初始pH为1.4、静置时间为30 min的条件下,处理30 mL Cr(Ⅵ)质量浓度为126.5 mg/L的含铬废水,适宜的脱硫废碱液加入量为6 mL,此条件下Cr(Ⅵ)转化率接近10... 相似文献
12.
13.
可持续发展能力建设的理论分析与重构 总被引:8,自引:1,他引:7
本文从《21 世纪议程》所述的可持续发展能力的解释出发,首次定义了可持续发展能力建设的概念,全面阐术述了能力建设的基本概念和实质内涵;同时,从理论上论述了能力建设的现实意义、能力建设的途径以及能力建设在实施可持续发展战略中基础作用。 相似文献
14.
Controlling cyanobacterial blooms by managing nutrient ratio and limitation in a large hypereutrophic lake: Lake Taihu, China 总被引:1,自引:0,他引:1
Excessive nitrogen (N) and phosphorus (P) loading of aquatic ecosystems is a leading cause of eutrophication and harmful algal blooms worldwide, and reducing nutrient levels in water has been a primary management objective. To provide a rational protection strategy and predict future trends of eutrophication in eutrophic lakes, we need to understand the relationships between nutrient ratios and nutrient limitations. We conducted a set of outdoor bioassays at the shore of Lake Taihu. It showed that N only additions induced phytoplankton growth but adding only P did not. Combined N plus P additions promoted higher phytoplankton biomass than N only additions, which suggested that both N and P were deficient for maximum phytoplankton growth in this lake (TN:TP = 18.9). When nutrients are present at less than 7.75-13.95 mg/L TN and 0.41-0.74 mg/L TP, the deficiency of either N or P or both limits the growth of phytoplankton. N limitation then takes place when the TN:TP ratio is less than 21.5-24.7 (TDN:TDP was 34.2-44.3), and P limitation occurs above this. Therefore, according to this ratio, controlling N when N limitation exists and controlling P when P deficiency is present will prevent algal blooms effectively in the short term. But for the long term, a persistent dual nutrient (N and P) management strategy is necessary. 相似文献
15.
16.
In China, volatile organic compound(VOC) control directives have been continuously released and implemented for important sources and regions to tackle air pollution. The corresponding control requirements were based on VOC emission amounts(EA), but never considered the significant differentiation of VOC species in terms of atmospheric chemical reactivity. This will adversely influence the effect of VOC reduction on air quality improvement. Therefore,this study attempted to develop a comprehensive classification method for typical VOC sources in the Beijing–Tianjin–Hebei region(BTH), by combining the VOC emission amounts with the chemical reactivities of VOC species. Firstly, we obtained the VOC chemical profiles by measuring 5 key sources in the BTH region and referencing another 10 key sources, and estimated the ozone formation potential(OFP) per ton VOC emission for these sources by using the maximum incremental reactivity(MIR) index as the characteristic of source reactivity(SR). Then, we applied the data normalization method to respectively convert EA and SR to normalized EA(NEA) and normalized SR(NSR) for various sources in the BTH region.Finally, the control index(CI) was calculated, and these sources were further classified into four grades based on the normalized CI(NCI). The study results showed that in the BTH region,furniture coating, automobile coating, and road vehicles are characterized by high NCI and need to be given more attention; however, the petro-chemical industry, which was designated as an important control source by air quality managers, has a lower NCI. 相似文献
17.
螺旋型垂直筛板布气的喷射鼓泡脱硫除尘塔的研制和性能 总被引:1,自引:0,他引:1
研制了一种中试规模的螺旋型垂直筛板布气的喷射鼓泡脱硫除尘装置,具有螺旋型布气、环流布气、气动搅拌等特点.装置中特有的螺旋型气室是由两块按阿基米德螺线设计的垂直筛板围成,有结构简单紧凑、开孔面积大、不容易堵塞、气速稳定等优点.对中试规模装置进行了压降和湿法脱硫除尘实验.结果表明:空塔与喷射鼓泡运行时装置各部分压降随气量增加而增加,喷射鼓泡运行中控制"临界液位差"约170mm,当气量为1856m.3h-1时,塔总压降为3.37kPa;脱硫效率随鼓泡层高度和气动搅拌器旋转速度的增加而升高;当石灰石浆液浓度上升时,pH升高,有效脱硫时间延长;pH是控制装置脱硫效率的关键,pH=5.35时脱硫效率可达70%,pH为6~7时脱硫效率保持在80%以上;当烟气中含尘浓度大于304mg.m-3时(粉尘粒径小于50μm),除尘效率可达91%以上;该装置脱硫、除尘效率高,塔体高度较低,结构紧凑,具有很好的应用前景. 相似文献
18.
研究了氯化钙(Chlo-Ca)、螯合钙(Che-Ca)和纳米钙(Nano-Ca)对甜樱桃Cerasus pseudocerasus(Lind l.)G.Don贮藏品质及钙形态的影响,并采用焦锑酸钾沉淀-透射电子显微镜观察了不同钙处理樱桃贮藏后果肉细胞的超微结构特点。结果表明,Che-Ca处理提高了果实硬度,且有效的抑制了樱桃贮藏后硬度的降低和VC的消耗,但对果实采摘时维生素C含量影响差异不显著。3种钙处理增加了樱桃可溶性固形物的含量,对可溶性糖、可滴定酸和糖/酸影响较小。喷钙处理樱桃的全钙、水提取钙(H2O-Ca)、乙醇提取钙(ALc-Ca)的含量均有不同程度增加。樱桃果肉中的钙主要以ALc-Ca的形式存在,且Che-Ca处理中的ALc-Ca所占比例要显著高于Chlo-Ca和Nano-Ca处理。贮藏后NaCl溶液提取钙(NaCl-Ca)、H2O-Ca和ALc-Ca含量下降,醋酸提取钙(HAC-Ca)和盐酸溶液提取钙(HCl-Ca)的含量有所上升。贮藏60d后的樱桃细胞超微结构照片显示对照处理的细胞壁有断裂,细胞膜系统部分消失,细胞内较干净,且少部分细胞有收缩现象,3种钙处理,细胞壁结构比较完整,发现较多的黑色物质存在,不均衡的分布于细胞壁、细胞膜、液泡膜和线粒体等系统中。 相似文献
19.
ABSTRACTContinuously reducing the CO2 intensity of GDP is the core strategy for developing countries to realize the dual targets of economic growth and CO2 emissions reduction. The measures are twofold: one is to strengthen energy saving and decrease energy intensity of GDP and the other is to promote energy structural decarbonization and reduce CO2 intensity of energy consumption. In order to control global temperature rise no more than 2°C, the decrease in CO2 intensity of GDP needs surpass 4% before 2030, but it could be merely about 2% based on the current trend. Therefore, all countries ought to speed up the low-carbon transition in energy and economy. As for China, keeping a continuous decline in CO2 intensity of GDP of 4%–5% will ensure the realization of the NDC objectives, and also promotes the early peaking of CO2 emissions before 2030. China will play a positive leading role in realizing a win-win low-carbon development coordinating sustainable development and climate change mitigation. 相似文献
20.
分析现有中药废水处理工艺及废水特点,并考虑到废水处理技术改造的要求,采用水解酸化-SBR-BAF法联合处理该中药废水,研究了SBR反应器的曝气时间、温度及原水pH值对系统处理效果的影响。系统进水ρ(COD)为1 249.4~1 444.5 mg/L、ρ(BOD5)为201.2~292.8 mg/L、ρ(SS)为208.7~310.6 mg/L、色度为70~100倍,曝气时间为14 h、温度为20℃、pH值为7时,出水ρ(COD)为123.4~140.8 mg/L、ρ(BOD5)为19.4~26.1 mg/L、ρ(SS)为32.7~60.4 mg/L、色度为36~50倍,COD、BOD5、SS的平均去除率分别达到90.3%、90.7%、81.8%,表明HAT-SBR-BAF法处理该中药废水是可行的。 相似文献