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261.
为提高不同粒径段大气颗粒物质量浓度及化学组成测量数据的准确性,使用惯性撞击式采样器对北京、千烟洲和鼎湖山3个站点的大气颗粒物分9个粒径段进行了采集,从质量浓度偏差和化学组成的角度进行了方法学探讨.结果表明,在恒温25℃、恒湿50%平衡条件下,称量石英材质的采样膜获得的PM2.1质量浓度相对于TEOM在线PM2.5观测结果的正偏差为20%左右,正偏差诱因是环境空气相对湿度过高.干燥(10% 湿度,25℃)微环境平衡处理方法有利于采样后膜片中H2O析出,使得上述正偏差降低至8%.通过条件实验,确定了石英膜采样前后在干燥器中放置72h平衡后称重、差减获得各级质量浓度的方法,可将偏差控制在可接受范围之内.基于这种方法获得的PM2.1质量浓度与TEOM在线PM2.5观测结果呈显著线性相关(R2=0.89,P<0.05).为达到通过化学成分重构质量浓度的需求,建立了同步使用石英膜采集样品并用于水溶性成分、有机碳和元素碳含量分析,而使用纤维素膜采样后用于金属元素分析的方案.应用上述方案对样品进行了全化学分析,对PM2.1质量进行了重构,重构获得的质量浓度与称重获得PM2.1质量浓度也呈显著线性相关(R2=0.89,P<0.05). 相似文献
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DIOGO VERÍSSIMO TATIANA PONGILUPPI MARIA CINTIA M. SANTOS PEDRO F. DEVELEY IAIN FRASER ROBERT J. SMITH DOUGLAS C. MACMILAN 《Conservation biology》2014,28(1):269-277
Conservation marketing campaigns that focus on flagship species play a vital role in biological diversity conservation because they raise funds and change people's behavior. However, most flagship species are selected without considering the target audience of the campaign, which can hamper the campaign's effectiveness. To address this problem, we used a systematic and stakeholder‐driven approach to select flagship species for a conservation campaign in the Serra do Urubu in northeastern Brazil. We based our techniques on environmental economic and marketing methods. We used choice experiments to examine the species attributes that drive preference and latent‐class models to segment respondents into groups by preferences and socioeconomic characteristics. We used respondent preferences and information on bird species inhabiting the Serra do Urubu to calculate a flagship species suitability score. We also asked respondents to indicate their favorite species from a set list to enable comparison between methods. The species’ traits that drove audience preference were geographic distribution, population size, visibility, attractiveness, and survival in captivity. However, the importance of these factors differed among groups and groups differed in their views on whether species with small populations and the ability to survive in captivity should be prioritized. The popularity rankings of species differed between approaches, a result that was probably related to the different ways in which the 2 methods measured preference. Our new approach is a transparent and evidence‐based method that can be used to refine the way stakeholders are engaged in the design of conservation marketing campaigns. 相似文献
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海岛旅游发展再一次成为海洋旅游业发展的新突破口.以湄洲岛为代表的文化型海岛凭借其深厚的文化内涵和优质的海滨旅游资源成为海洋旅游业发展的生力军.从解读文化型海岛内涵及特征入手,全面剖析了湄洲岛的优势条件,从文化价值、文化需求、文化生态、文化形态等方面深入挖掘湄洲岛所含文化特性,以此构建起湄洲岛善行旅游发展的“四和四共一发展”的互动效应,探寻出一条具有文化型海岛特点的湄洲岛善行旅游发展之路. 相似文献
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社区居民的贡献意愿研究是进行湿地保护的重要切入点。以大庆湿地社区为案例地,设计了“仅金钱”“仅劳动”“两者皆愿意”“两者皆不愿”4个贡献意愿类型,通过问卷调查统计社区居民的贡献意愿现状,并运用MNL模型分析社区居民个人特征对贡献意愿选择偏好的倾向性影响及边际影响。研究结论如下:第一,79.8%的社区居民对湿地保护具有贡献意愿,劳动贡献意愿高于金钱贡献意愿;第二,性别、年龄、月收入、受教育程度、加入环保组织、接受过环保教育为社区居民贡献意愿选择偏好的关键影响因素;第三,提高社区居民的受教育程度和月收入、让社区居民加入环保组织和进行环保宣传可以显著提升社区居民的贡献意愿水平。研究将劳动作为一种直观的贡献价值进行体现,使对贡献意愿的研究不再仅仅局限于货币形式。建议湿地管理者应重视针对湿地社区的环保宣传与环保组织运作,重视劳动形式在环保贡献中的重要作用。 相似文献
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Individuals’ food choices are intimately connected to their self-images and world views. Some dietary choices adopted by consumers
pose restrictions on their use of genetically modified food (GMF). It is quite generally agreed that some kind of labeling
is necessary for respecting consumers’ autonomy of choice regarding GMF. In this paper, we ask whether the current practice of mandatory
labeling of GMF products in the European Union is a sufficient administrative procedure for respecting consumers’ autonomy. Three issues concerning this question are discussed. First,
we argue that labeling needs to be accompanied by relevant and understandable information on genetic modification, genetically
modified food, and the European practice of GMF labeling. Second, we claim that this type of informing makes it less likely
that consumers start to avoid GMF products just because labels make them suspicious of the products. It is further noted that
even though some consumers may react to labels this way, labels do not restrict their autonomy of choice. Third, a need for
more precise labels indicating the source of the transferred gene is considered. It is found out that such labels are not
morally necessary when also non-GMF products are available and no relevant differences (such as differences in price and healthiness)
exist between them and GMF products. However, in some other cases more precise labels may be needed for respecting consumers’
autonomy of choice. 相似文献
269.
Jane L. Halliday Rosemary Warren Geraldine McDonald Pranee Liamputtong Rice Robin J. Bell Lyndsey F. Watson 《黑龙江环境通报》2001,21(10):842-847
Forty percent of pregnant women aged 37 years and over do not have prenatal diagnosis despite being eligible for a free test. The present study aimed to determine how often, and which, untested women were making a choice about this, how many declined an offer and why. A questionnaire was given to untested women, aged 37 years and over, at no less than 24 weeks gestation. A total of 375 (81.5%) women declined, 72 (16%) were not offered a test and 13 presented too late antenatally. There was a three-fold increased likelihood (OR 3.10 95% CI 1.44, 6.65) of no offer for urban non-English speaking background women, compared with the reference group (metropolitan, English speaking). Unpartnered women were also significantly less likely to receive an offer (OR 3.18, 95% CI 1.19, 8.46). Risk to the baby was the main reason for declining. When offered non-invasive prenatal screening, most decliners of prenatal diagnosis accepted, even those who declined because they were opposed to abortion. We estimate that overall 33% of older pregnant women were being offered and declining amniocentesis and/or chorion villus sampling (CVS). Only 6% were not offered a test, but this small proportion is over-represented by minority groups who must be given equal opportunity to make this choice. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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