全文获取类型
收费全文 | 366篇 |
免费 | 52篇 |
国内免费 | 70篇 |
专业分类
安全科学 | 122篇 |
废物处理 | 4篇 |
环保管理 | 24篇 |
综合类 | 226篇 |
基础理论 | 30篇 |
污染及防治 | 12篇 |
评价与监测 | 20篇 |
社会与环境 | 35篇 |
灾害及防治 | 15篇 |
出版年
2024年 | 6篇 |
2023年 | 10篇 |
2022年 | 21篇 |
2021年 | 21篇 |
2020年 | 27篇 |
2019年 | 13篇 |
2018年 | 16篇 |
2017年 | 17篇 |
2016年 | 15篇 |
2015年 | 17篇 |
2014年 | 17篇 |
2013年 | 28篇 |
2012年 | 35篇 |
2011年 | 40篇 |
2010年 | 40篇 |
2009年 | 28篇 |
2008年 | 36篇 |
2007年 | 27篇 |
2006年 | 24篇 |
2005年 | 20篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 5篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1995年 | 1篇 |
排序方式: 共有488条查询结果,搜索用时 15 毫秒
171.
大气污染物多时间分辨率的小波分析 总被引:3,自引:1,他引:2
利用Modet小波函数进行小波变换,利用Daubechies小波函数进行分解及滤波,以乌鲁木齐市的大气污染物时间序列为例,分析了当地单个大气监测站点NO2的多分辨率的演变特性,并对NO2的时间序列进行了滤波消噪.研究结果显示,NO2年际变化和季节性变化的时间尺度在尺度空间中分布不均匀,具有较明显的局部化特征;除了季节性变化的时间尺度和变化趋势之外,还存在大气污染物中、长期变化趋势.基于滤波消噪后的时间序列建立的预测模型可用于有效地提高大气污染物的预测预报精度. 相似文献
172.
ZHANG Yejian YAN Li QIAO Xiangli CHI Lin NIU Xiangjun MEI Zhijian ZHANG Zhenjia 《环境科学学报(英文版)》2008,20(5):558-564
Palm oil industry is the most important agro-industry in Malaysia, but its by-product–palm oil mill e uent (POME), posed a great
threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to
solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic
biodegradation constituted the first biological stage, while ultrafiltration (UF) and reverse osmosis (RO) membrane units were combined
as the second membrane separation stage. In the anaerobic expanded granular sludge bed (EGSB) reactor, about 43% organic matter
in POME was converted into biogas, and COD reduction e ciency reached 93% and 22% in EGSB and the following aerobic reactor,
respectively.With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated
the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured
by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole
treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and
color were not detectable in RO permeate any more, and mineral elements only existed in trace amount (except for K and Na). The
high-quality e uent was crystal clear and could be used as the boiler feed water. 相似文献
173.
ZHANG Yejian YAN Li QIAO Xiangli CHI Lina NIU Xiangjun MEI Zhijian ZHANG Zhenjia 《环境科学学报(英文版)》2008,20(5)
Palm oil industry is the most important agro-industry in Malaysia, but its by-product-palm oil mill effluent (POME), posed a great threat to water environment. In the past decades, several treatment and disposal methods have been proposed and investigated to solve this problem. A two-stage pilot-scale plant was designed and constructed for POME treatment. Anaerobic digestion and aerobic biodegradation constituted the first biological stage, while ultrafiltration (UF) and reverse osmosis (RO) membrane units were combined as the second membrane separation stage. In the anaerobic expanded granular sludge bed (EGSB) reactor, about 43% organic matter in POME was converted into biogas, and COD reduction efficiency reached 93% and 22% in EGSB and the following aerobic reactor, respectively. With the treatment in the first biological stage, suspended solids and oil also decreased to a low degree. All these alleviated the membrane fouling and prolonged the membrane life. In the membrane process unit, almost all the suspended solids were captured by UF membranes, while RO membrane excluded most of the dissolved solids or inorganic salts from RO permeate. After the whole treatment processes, organic matter in POME expressed by BOD and COD was removed almost thoroughly. Suspended solids and color were not detectable in RO permeate any more, and mineral elements only existed in trace amount (except for K and Na). The high-quality effluent was crystal clear and could be used as the boiler feed water. 相似文献
174.
强化接触氧化法处理高盐废水 总被引:3,自引:1,他引:2
废水中盐分含量过高,会给生物处理带来一定的难度。因为盐析作用可致使微生物的脱氢酶活性降低,同时水的渗透压也会升高,使微生物细胞脱水引起细胞原生质分离,从而导致微生物细胞破裂而死亡。传统的一些生物方法对此类废水的COD的去除率低。本试验使用两株嗜盐菌在接触氧化反应器中通过连续操作对含盐废水进行处理,研究了盐度,COD负荷,溶氧对COD去除率的影响关系。在废水盐度为35g/L,进水COD为4500mg/L,COD容积负荷为3.5kgCOD(/m·3d)时,COD去除率达到90%左右,取得较好的去除效果。 相似文献
175.
176.
177.
安全哲学为人类安全提供认识论和方法论的指导。基于唯物辩证法联系和发展的观点,分析企业安全文化和企业文化的辩证关系,认为企业安全文化建设依赖于企业文化基础,融入企业文化建设之中,融入企业文化的发展规划、决策,渗透到企业文化建设诸项内容中去。探讨企业安全文化的哲学诉求,认为企业安全文化的哲学是以"以人为本"为依据。对中国石化管道企业文化和企业安全文化进行阐述,对企业安全核心理念逐一进行哲学诠释。 相似文献
178.
179.
180.
贵屿某电子垃圾拆解点附近大气颗粒物中氯代/溴代二噁英、四溴双酚A污染水平研究 总被引:2,自引:0,他引:2
对贵屿某电子垃圾拆解点附近大气颗粒物中氯代二英(PCDD/Fs)、溴代二英(PBDD/Fs)、四溴双酚A(TBBPA)含量水平进行了调查研究.结果显示,大气颗粒物中17种2,3,7,8-PCDD/Fs和8种2,3,7,8-PBDD/Fs的浓度范围分别为126.54~524.78pg·m-3和376.42~566.76pg·m-3;平均毒性当量(TEQ)分别为16.29pg·m-3、91.28pg·m-3,均高出目前所报道的国内外其它部分城市大气污染水平1~4个数量级,且PBDD/Fs的污染水平远远高于PCDD/Fs.四氯至八氯代PCDD/Fs同系物呈现出明显且特别的分布规律,PCDDs和PCDFs浓度均随着氯原子取代程度增加而降低.TBBPA的浓度范围为66.01~95.04ng·m-3,大气中PBDD/Fs浓度与之显著相关r=0.69.初步的暴露风险评价表明,当地居民每日通过呼吸摄入的二英含量远远超过了世界卫生组织(WHO)规定的人体每日耐受量(TDI)1~4pg(W-TEQ)·kg-·1d-1. 相似文献