首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   322篇
  免费   30篇
  国内免费   97篇
安全科学   33篇
废物处理   8篇
环保管理   41篇
综合类   149篇
基础理论   45篇
环境理论   6篇
污染及防治   69篇
评价与监测   8篇
社会与环境   70篇
灾害及防治   20篇
  2023年   8篇
  2022年   10篇
  2021年   14篇
  2020年   8篇
  2019年   23篇
  2018年   40篇
  2017年   32篇
  2016年   21篇
  2015年   26篇
  2014年   16篇
  2013年   42篇
  2012年   23篇
  2011年   15篇
  2010年   17篇
  2009年   20篇
  2008年   9篇
  2007年   25篇
  2006年   20篇
  2005年   13篇
  2004年   12篇
  2003年   9篇
  2002年   12篇
  2001年   10篇
  2000年   4篇
  1999年   6篇
  1998年   3篇
  1997年   2篇
  1996年   4篇
  1993年   1篇
  1987年   2篇
  1974年   1篇
  1971年   1篇
排序方式: 共有449条查询结果,搜索用时 31 毫秒
71.
生物炭颗粒在多孔介质中的迁移行为不仅决定了其在环境中的归趋,也极大地影响了被吸附污染物的环境行为.以往的研究主要集中在生物炭胶体在均性多孔介质中的迁移行为,但实际环境介质通常是非均性的,目前对生物炭胶体在非均性多孔介质中的迁移行为知之甚少.本研究采用两种不同粒径的石英砂构建了上下两层非均性填充柱(上层细颗粒,下层粗颗粒),研究了生物炭胶体在非均性多孔介质中的迁移和截留行为,考察了溶液离子强度和pH对生物炭胶体迁移能力的影响.研究结果表明在非均性多孔介质中,生物炭胶体具有很高的迁移能力,在离子强度为1~50 mmol·L-1,pH为4.0~11.0条件下,生物炭胶体的迁移率达40.2%~88.0%.非均性介质中生物炭胶体的截留曲线表现为非单调型曲线,截留量峰值往往出现在细-粗石英砂的交界面处(细石英砂侧),这与非均性介质中显著的电荷异质性、介质尺寸异质性和迁移过程中传质通量异质性有关.生物炭胶体在上层细石英砂中的截留量显著大于其在下层粗石英砂中的截留量,表明上层细石英砂是影响生物炭胶体迁移行为的关键层.随着溶液离子强度增加,生物炭胶体自团聚作用增强,其与石英砂介质间界面作用能垒降低,因而生物炭胶体的迁移能力减弱.由于生物炭胶体与细石英砂间的物理张力作用趋于显著,增加离子强度提高了生物炭胶体在上层细石英砂中的截留比率.中性和碱性条件下生物炭胶体的迁移能力较强,而在酸性条件下,生物炭胶体表面电负性显著降低,团聚体粒径增大,生物炭胶体的迁移能力较弱.降低溶液pH增加了生物炭胶体在上层细石英砂中的截留比率.本研究的结果将有利于人们更好地了解生物炭胶体在复杂多孔介质中的迁移行为,为全面评估生物炭的潜在环境风险提供理论支持.  相似文献   
72.
Ulrich Beck's World Risk Society is becoming an increasingly relevant analysis of contemporary human/environment interaction. However, with this said, Beck's observations remain broad and significantly lacking empirical evidence. This paper explores the relationship between sustainable lifestyles and assertions of one of Beck's central ideas, the emergence of a reflexive modernity at the local scale. By empirically examining the motivation of participants for joining a scheme designed to enhance sustainable lifestyles, this paper will progressively outline the way that individuals in a risk society negotiate global images in a local context and what this means for a reflexive modernity. By exposing the complex interaction of global risk imagery and the effect this has on achieving local sustainability, a more realistic understanding of Beck's theoretical assertions can be applied to an increasingly important policy arena.  相似文献   
73.
74.
This study aims to explore how the Turkish press represents the discourse of climate change scientists. This is achieved by analyzing climate change-related articles that quote scientists, directly and indirectly, in two Turkish mainstream newspapers (N = 132, 7 years). The Turkish case illustrates how scientific rhetoric is used for presenting climate change as a matter of concern in an industrializing country. The analysis suggests that climate science is portrayed as an un-discussed authority. News articles rely on data about the disturbance of species and the state of the natural environment to provide proof of global warming, by which they produce an implicit moral imperative. The articles also portray the worst threats and challenges—those pertaining to human society—as residing mostly in the future. We conclude by discussing the implications of the use of a projected future to convey a discourse emphasizing the alarming risks associated with climate change.  相似文献   
75.
ABSTRACT

What people believe about the beliefs of other people – second-order beliefs – has been acknowledged as a key factor that shapes public support for international climate policy. However, very little is known about their origins. Based on data from an online survey (n?=?935), we analyzed how German citizens assess the climate change awareness in their own nation as compared to those of the US and China. Even if the public climate change awareness in the US and China factually differs, we found that German citizens equivalently rate both nations similar and much lower than their own, a finding which can be explained with social identity processes and “in-group”/“out-group” biases. Hierarchical regression analyses demonstrate that the attention individuals pay towards television and social media predict second-order beliefs on climate change awareness positively, while attention to print media is a negative predictor.  相似文献   
76.
ABSTRACT

Mermaids: The Body Found privileges mythologized creatures in a fictional narrative disguised as a documentary film in order to blur the boundaries between fact and fiction. This franchise’s decisions to value factors of entertainment over educational material are not uncommon in our consumer-driven society, but the film's engagement with fake fact media potentially repositions how audiences think about important conservation issues by overshadowing critical oceanic environmental topics with fake facts. Although today’s viewers are adept in interpreting media, the mermaid franchise’s use of screen genres, corporate websites, and social media saturates viewers with fake facts making it difficult to delineate between authentic science and fictional narrative. Not a quantitative reception study of audiences, this critical analysis of multiple genres of eco-media examines the difference between fake nature documentary and other types of animal programming and mockumentaries emphasizing that the issue is not strictly a question of entertainment factors or even of the subversion of fact and fiction, alone, but that the real issue lies in the franchise’s willingness to participate in an ever-growing media moment in which programming based on fake and alternative facts has the potential to impact how the public thinks about key issues in politics and science.  相似文献   
77.
ABSTRACT

To understand haze-related online communication in Southeast Asia, this exploratory study took a mixed method approach to conduct web analysis of online communication during haze crisis in Singapore, followed by textual analysis of traditional and new media content during peak days. First, web analytics showed that Singapore’s haze online communication occurred mostly on the Twitter platform with primary negative sentiments. Next, textual analysis results found that majority of traditional media-affiliated news provided informative haze reports and centered on positive measurements taken by government and authorities, similar to Public Information Model for crisis management. In comparison, haze-related new media content had diverse topics reflecting laymen’s viewpoints with critical tones and negative sentiments. News portals and blogs used two-way asymmetrical and symmetrical model for crisis management, respectively. Additionally, Social Cognitive Theory’s media diversity perspectives were applied to understand people’s media choices among traditional and new media during natural crisis with environmental influences.  相似文献   
78.
易成豪  秦伟  陈湛  文湘华 《环境科学》2019,40(9):4143-4151
以可生物降解聚合物聚己内酯(PCL)和聚羟基丁酸戊酸酯(PHBV)作为反硝化缓释碳源和微生物载体,利用清水释碳和批式反硝化试验选出适用于再生水反硝化深度脱氮生物滤池的可生物降解碳源滤料,通过比较与分析碳源滤料的表面形态及物质特性和附着微生物的群落特征揭示其性能优越的原因.结果表明,PHBV反硝化启动时间短,反硝化速率高,剩余有机物浓度低,相比PCL具有更稳定持续的反硝化效果.原因是其表面粗糙,且含有大量C—O和CO等亲水性基团,易于微生物附着和降解利用;其表面附着的微生物种类多样,其中发硫菌属(Thiothrix)、假单胞属(Pseudomonas)、菌胶团属(Zoogloea)、黄杆菌属(Flavobacterium)和脱氯菌属(Dechloromonas)等优势菌属均具有异养反硝化功能.因此,PHBV更适合作为再生水反硝化深度脱氮生物滤池的碳源滤料.  相似文献   
79.
基于网络的交通安全宣传教育研究   总被引:1,自引:0,他引:1  
为了建立我国交通安全宣传教育网络平台,通过网络平台进行多形式的交通安全宣传教育。采用网站检索的方法,梳理了国内、外主要城市交通安全宣传教育网站,并从专业性、系统性、针对性、形式多样性等角度进行研究。研究发现国外交通安全网站具有分类细致、系统性强、参与互动性强等特点。因此建议我国应加快明确重点教育人群,建立系统性的、专业的、多形式的交通安全宣教内容,引入社会团体等加入宣传教育的队伍,提高全面积极参与、提高关注度。  相似文献   
80.
以沉淀-回流方法于磷酸银(Ag3PO4)中掺杂氮化碳(g-C3N4)制备新型复合光催化剂,同时采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射图(XRD)等手段对合成催化剂的形态特征、晶型结构以及物理化学性质进行表征.以碘帕醇(IPM)作为目标污染物,通过改变催化剂的使用条件考察了氙灯光照下催化剂对水溶液中含碘类造影剂(ICMs)的光催化降解性能,并且分析了催化氧化过程中可能的污染物降解途径以及转化产物.结果表明,合成后的催化剂结构稳定,相对于使用单一催化剂(Ag3PO4或g-C3N4)条件下,复合催化剂对ICMs的光降解性能都得到大幅度提升,经条件优化后,确定Ag3PO4与g-C3N4的质量比例为0.15∶0.1时降解效果最佳,但不可超过0.2∶0.1,且降解性能与催化剂的投加浓度呈正相关,浓度在0.75 ...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号