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   126篇
  免费   0篇
  国内免费   1篇
安全科学   3篇
废物处理   7篇
环保管理   6篇
综合类   10篇
基础理论   27篇
污染及防治   46篇
评价与监测   18篇
社会与环境   6篇
灾害及防治   4篇
  2023年   3篇
  2022年   10篇
  2021年   5篇
  2020年   5篇
  2019年   3篇
  2018年   5篇
  2017年   14篇
  2016年   14篇
  2015年   4篇
  2014年   17篇
  2013年   15篇
  2012年   3篇
  2011年   4篇
  2010年   1篇
  2009年   5篇
  2008年   3篇
  2007年   3篇
  2006年   3篇
  2005年   2篇
  2003年   1篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1998年   1篇
  1981年   1篇
排序方式: 共有127条查询结果,搜索用时 15 毫秒
31.
Disaster mitigation and preparedness on the Nicaraguan post-Mitch agenda   总被引:3,自引:0,他引:3  
Rocha JL  Christoplos I 《Disasters》2001,25(3):240-250
Nicaragua provides an example of how a major disaster, in this case Hurricane Mitch, can transform the national agenda for disaster mitigation and preparedness. Hurricane Mitch was a reminder of how extremely disaster prone Nicaragua is, and also how neoliberal reforms have weakened governmental response capacity. In the face of critiques of how governmental policies had affected preparedness and response, discussions of this transformation became a highly politicised process where the debate over alternative development models tended to overshadow the original calls to strengthen risk management. Progress can be seen in some areas, such as disaster mitigation through environmental management. This study of NGO roles, and their relations with other key actors, draws attention to the need to anchor improved risk management in local-level NGO-government collaboration. Structures are being put into place to achieve this aim, but dependence on donor financing raises questions regarding the longer-term sustainability of these efforts.  相似文献   
32.
The shrimp farming has been converted into a mature aquaculture industry dealing with over millions of metric tonnes of processed commodities. Nevertheless, the global shrimp productions are constantly threatened by disease outbreaks, mainly triggered by rapidly disseminating viruses. Infectious myonecrosis virus (IMNV) is one of these epizootic agents affecting shrimp production in Brazil, of which no treatment exists. Herein, the antiviral activity against IMNV of an eicosapeptide, named Ctn[15-34], derived from a member of the cathelicidin family of antimicrobial peptides, was demonstrated. Cultures of hemocytes from Litopenaeus vannamei were established that support IMNV replication and infectivity titration. The cytotoxic effect of IMNV in culture and the in vitro anti-IMNV activity of Ctn[15-34] were assessed using a high-sensitive fluorescent-based method in combination with quantitative PCR. The Ctn[15-34] (<12.5 µM) neutralized the toxic effects of IMNV at loads sufficient to kill 50% of shrimp hemocytes. This study reported for the first time the replication of IMNV in vitro and the employment of a straightforward methodology to assess cell viability and viral/antiviral activities. In addition, it provided the basis for the development of the anti-infective multi-effector Ctn[15-34] eicosapeptide and analogs as components of antiviral formulations against shrimp viral diseases.  相似文献   
33.

In addition to direct photolysis studies, in this work the second-order reaction rate constants of pesticides imidacloprid (IMD) and ametryn (AMT) with hydroxyl radicals (HO), singlet oxygen (1O2), and triplet excited states of chromophoric dissolved organic matter (3CDOM*) were determined by kinetic competition under sunlight. IMD and AMT exhibited low photolysis quantum yields: (1.23?±?0.07)?×?10–2 and (7.99?±?1.61)?×?10–3 mol Einstein?1, respectively. In contrast, reactions with HO radicals and 3CDOM* dominate their degradation, with 1O2 exhibiting rates three to five orders of magnitude lower. The values of kIMD,HO● and kAMT,HO● were (3.51?±?0.06)?×?109 and (4.97?±?0.37)?×?109 L mol?1 s?1, respectively, while different rate constants were obtained using anthraquinone-2-sulfonate (AQ2S) or 4-carboxybenzophenone (CBBP) as CDOM proxies. For IMD this difference was significant, with kIMD,3AQ2S*?=?(1.02?±?0.08)?×?109 L mol?1 s?1 and kIMD,3CBBP*?=?(3.17?±?0.14)?×?108 L mol?1 s?1; on the contrary, the values found for AMT are close, kAMT,3AQ2S*?=?(8.13?±?0.35)?×?108 L mol?1 s?1 and kAMT,3CBBP*?=?(7.75?±?0.80)?×?108 L mol?1 s?1. Based on these results, mathematical simulations performed with the APEX model for typical levels of water constituents (NO3?, NO2?, CO32?, TOC, pH) indicate that the half-lives of these pesticides should vary between 24.1 and 18.8 days in the waters of the Paranapanema River (São Paulo, Brazil), which can therefore be impacted by intensive agricultural activity in the region.

  相似文献   
34.
Environmental Science and Pollution Research - One of the most widely used antibiotics is amoxicillin (AMX), which is the most widely used in humans and animals, but it is discharged metabolically...  相似文献   
35.
Environmental Science and Pollution Research - Pesticides have been used to kill pests such as insects, fungi, rodents, and unwanted plants. Since these compounds are potentially toxic to the...  相似文献   
36.
Invasion by alien species is one of the most critical factors affecting global biodiversity, leading to homogenization and species loss worldwide. Jackfruit (Artocarpus heterophyllus Lam., Moraceae) is one of the most conspicuous invasive plants in Brazil. We studied jackfruit invasion in the Atlantic Forest in Ilha Grande State Park, located on an island (Ilha Grande), by assessing jackfruit distribution and density along 23 trails (90 km). Presence or absence was verified in a total of 857 plots. Data showed that jackfruit is spread all over Ilha Grande, and that plant density varied significantly along and between trails. Jackfruit was registered as the dominant tree species on some of the trails. Control by park managers is an urgent need in order to ensure the conservation of local biodiversity. A decision key for jackfruit management according to jackfruit density, age class and slope is provided.  相似文献   
37.
Previous studies in the Douro River estuary, based on occasional sampling, showed the presence of several estrogenic disrupting chemicals (EDCs). In sequence, we hypothesized that such type of pollution was more likely an enduring issue than an occasional phenomenon, and that it may even affect recreational beaches in each side of the estuarine mouth. Thus to conclude about the continuous influx of EDCs, water samples were taken twice a day, once per a week, from March to May of 2009, at four sites within the estuary and at two sites in the coastline. After solid-phase extraction, the extracts were prepared for GC-MS analysis of 11 reference EDCs. These embraced natural and pharmaceutical estrogens (17β-estradiol, estrone and 17α-ethynylestradiol) and xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono and diethoxylates and bisphenol A). Data showed the ubiquitous presence of potentially hazardous amounts of natural estrogens (particularly of estradiol, ca 5.5?ng?L?1) and persistent organic pollutants such as nonylphenol mono (up to 550?ng?L?1) and diethoxylate (up to 2000?ng?L?1). It was concluded that the targeted area is continuously polluted by the assayed EDCs, and as a consequence, conditions exist for endocrine disturbance in the biota by chronic exposure to EDCs.  相似文献   
38.
The present study investigates into the link between people’s vulnerability in the face of coastal hazards and sustainable livelihoods. It focuses on the town of Borongan in the Philippines and draws on questionnaire-based surveys and focus group discussions. This research shows that local fishermen are often compelled to go out fishing despite pending typhoon or storm surge to sustain the daily needs of their family. Its also demonstrates that the capacity of these people to protect themselves from the threat is constrained by poor and fragile livelihoods. In the event of a crisis, the study argues that people resort to a range of adjustments on their daily life which is rooted in the strength and diversity of their livelihoods. To reduce people’s vulnerability and enhance capacities to face coastal hazards, the study fosters Community-Based Disaster Risk Reduction with special emphasis to sustainable livelihoods.  相似文献   
39.
Sodium metabisulfite is used in marine shrimp harvesting to prevent the occurrence of black spots. Shrimps are soaked in a sodium metabisulfite solution in ice, which is disposed of in sewages that run into marine canals, creating an environmental hazard. This study evaluates the toxicity and mutagenicity caused by sodium metabisulfite in sea waters and sediments collected in a shrimp farm in Cajueiro da Praia (Luis Correia), state of Piauí, Brazil, using the Allium cepa assay. Water and sediment samples were collected in the dry and in the rainy seasons, in three sites: upstream the shrimp farm (Site 1), at the point sodium metabisulfite is discharged (Site 2), and 100 m downstream the farm (Site 3). Three sample dilutions were used (50%, 25% and 10%) for all samples. A negative control (well water) and a positive control (copper sulfate 0.0006 mg mL−1) were used in each experiment. At the end of the 72-h exposure period, onion roots were measured and removed. Mutagenicity analysis included the determination of mitotic index, chromosomal aberrations and the detection of micronuclei; analysis of root size and mitotic index were used as an index of toxicity. The A. cepa assay revealed that the water and sediments samples collected in the Piauí coast contaminated with sodium metabisulfite induce toxicity. The results demonstrate that the assay may be used as a regular tool in the analysis of water parameters in shrimp farms in the coast of Piauí state, and in strategies to preserve the region’s marine ecosystem.  相似文献   
40.
Water is fundamental to the existence of life since it is essential to a series of activities, such as agriculture, power generation, and public and industrial supplies. The residual water generated by these activities is released into the environment, reaches the water systems, and becomes a potential risk to nontarget organisms. This paper reports the development and validation of a quantitative method, based on solid-phase extraction and liquid chromatography tandem mass spectrometry, for the simultaneous analysis of 18 pharmaceuticals and personal care products (PPCPs) and 33 pesticides in surface and drinking waters. The accuracy of the method was determined by calculating the recoveries, which ranged from 70 to 120 % for most pesticides and PPCPs, whereas limits of quantification ranged from 0.8 to 40 ng/L. After the validation step, the method was applied to drinking and surface waters. Pesticides and PPCPs were found in concentrations lower than 135.5 ng/L. The evaluation of different water sources with regard to contamination by pesticides and PPCPs has been quite poor in southern Brazil.  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