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141.
Understanding how governments orchestrate public engagement in energy infrastructure decisions has important implications for the relationship between energy transitions, democracy and justice, but existing research is deficient in focusing mainly on single case studies. In response, we conduct a multi-sectoral, comparative analysis for the first time to assess how UK governments have engaged publics, applying a novel mapping methodology that is systematic, longitudinal and cross-technology. Moreover, our focus embraces mechanisms of consultation and support measures (e.g. community benefits) and seeks to explain patterns of change using a pragmatist sociology framework. Findings indicate trends towards a reduced scope for public engagement alongside expanded encouragement of community benefits, but also important sectoral differences. On-shore wind moved towards giving local decision-makers significant control over decisions. Gas-fired power stations experienced continuity, with central government controlling consents and limited interest in community benefits. Fracking facilities received intense promotion of community benefits, alongside incremental moves to restrict local decision-making. We argue that the patterns observed reflect government beliefs about the scope for depoliticisation in concrete situations, in which the conjunction of technologies, sites and publics affects how and whether arrangements for public engagement change. These results raise challenges for how researchers seek to connect energy transitions and democracy.  相似文献   
142.
Tourism and hunting both generate substantial revenues for communities and private operators in Africa, but few studies have quantitatively examined the trade‐offs and synergies that may result from these two activities. We evaluated financial and in‐kind benefit streams from tourism and hunting on 77 communal conservancies in Namibia from 1998 to 2013, where community‐based wildlife conservation has been promoted as a land‐use that complements traditional subsistence agriculture. We used data collected annually for all communal conservancies to characterize whether benefits were derived from hunting or tourism. We classified these benefits into 3 broad classes and examined how benefits flowed to stakeholders within communities under the status quo and under a simulated ban on hunting. Across all conservancies, total benefits from hunting and tourism increased at roughly the same rate, although conservancies typically started generating benefits from hunting within 3 years of formation as opposed to after 6 years for tourism. Disaggregation of data revealed that the main benefits from hunting were income for conservancy management and food in the form of meat for the community at large. The majority of tourism benefits were salaried jobs at lodges. A simulated ban on trophy hunting significantly reduced the number of conservancies that could cover their operating costs, whereas eliminating income from tourism did not have as severe an effect. Given that the benefits generated from hunting and tourism typically begin at different times in a conservancy's life‐span (earlier vs. later, respectively) and flow to different segments of local communities, these 2 activities together may provide the greatest incentives for conservation on communal lands in Namibia. A singular focus on either hunting or tourism would reduce the value of wildlife as a competitive land‐use option and have grave repercussions for the viability of community‐based conservation efforts in Namibia, and possibly other parts of Africa.  相似文献   
143.
Parental-investment theory predicts that monogamy should be rare, and empirical evidence supports this prediction. Monogamy has generally been explained by either (1) a need for biparental care, or (2) a uniform distribution of limiting resources. By contrast, monogamy has evolved in several coral-reef fishes without biparental care, and many coral-reef fishes may not be limited by resources. Monogamy in these fishes might be explained by either (3) a low population density that favors mate fidelity, or (4) an abundance of resources that allows all males to breed and thus lowers the cost-benefit ratio for females that mate guard. We tested predictions of these hypotheses in the coral-reef fish, Valenciennea strigata, except that (1) biparental care had previously been rejected. We found no evidence of resource limitation (2a): food densities within territories did not differ from the density of food in unused habitat adjacent to territories; potential nest sites also existed in this unused habitat. Similarly, (2b) if resources limit the population, territory defense might require the coordinated efforts of a pair; however, widowed fish maintained their territories and (3) remated rapidly. Finally, (4) all males maintained a nest, both sexes enforced monogamy by mate guarding, and females benefited from guarding a high-quality (large) mate. Females mated to large males fed more than when they paired with small males. The results support the hypothesis that abundant and uniformly distributed resources can lead to monogamy by lowering the cost of guarding a mate when mate guarding provides benefits. Received: 25 November 1997 / Accepted after revision: 29 December 1997  相似文献   
144.
Abstract

Objective: The objective of this research study is to estimate the benefit to pedestrians if all U.S. cars, light trucks, and vans were equipped with an automated braking system that had pedestrian detection capabilities.

Methods: A theoretical automatic emergency braking (AEB) model was applied to real-world vehicle–pedestrian collisions from the Pedestrian Crash Data Study (PCDS). A series of potential AEB systems were modeled across the spectrum of expected system designs. Both road surface conditions and pedestrian visibility were accounted for in the model. The impact speeds of a vehicle without AEB were compared to the estimated impact speeds of vehicles with a modeled pedestrian detecting AEB system. These impacts speeds were used in conjunction with an injury and fatality model to determine risk of Maximum Abbreviated Injury Scale of 3 or higher (MAIS 3+) injury and fatality.

Results: AEB systems with pedestrian detection capability, across the spectrum of expected design parameters, reduced fatality risk when compared to human drivers. The most beneficial system (time-to-collision [TTC]?=?1.5?s, latency = 0?s) decreased fatality risk in the target population between 84 and 87% and injury risk (MAIS score 3+) between 83 and 87%.

Conclusions: Though not all crashes could be avoided, AEB significantly mitigated risk to pedestrians. The longer the TTC of braking and the shorter the latency value, the higher benefits showed by the AEB system. All AEB models used in this study were estimated to reduce fatalities and injuries and were more effective when combined with driver braking.  相似文献   
145.
Inbreeding has negative effects on individual and population performances. Therefore, enhancement of offspring genetic diversity is believed to play a major role in shaping mating systems. However, no study has clearly separated the direct effect of having multiple partners from the indirect effect of having more outbred offspring on the resulting reproductive success of individuals in the wild. In this study, we report significant associations between both multiple mating and within-individual genetic diversity of offspring, and an increased reproductive success of wild female Atlantic salmon, Salmo salar. Specifically, we found that females with a higher number of mates also have more outbred offspring (within-individuals), and that both of these characteristics increased their reproductive success expressed in terms of offspring surviving when combining all freshwater juvenile stages. Our findings also indicate that determinants of fitness are different among sexes as within-individual offspring genetic diversity was not a strong predictor of male reproductive success, while the number of mates was important. We also show that females mated with more outbred males than on average, which potentially increased their chances of producing outbred offspring. These results therefore suggest that there could be more important indirect genetic benefits of multiple mating for females than for males.Communicated by M. Abrahams  相似文献   
146.
煤矿生产中瓦斯事故的发生及其危害程度的不确定性使得定量评价损失很困难.本文提出一种评估煤矿瓦斯事故严重程度和相关安全投资效益的方法.通过分析影响煤矿瓦斯事故发生的主要因素,利用专家调查法推断出瓦斯事故的发生概率和严重程度,进而估计出瓦斯事故的风险度并定量评价相关的安全投资效益.通过这种方法,可以提出各种安全投资方案并进行安全投资效益比较,据此选择安全投资效益最好的安全投资方案进行安全投资决策,最大限度地降低煤矿瓦斯事故的发生概率和危害程度.实例分析表明这种方法是有效的.  相似文献   
147.
碳达峰能源政策可同时实现减污降碳,带来明显的空气质量改善及人群健康效益.本研究综合利用LEAP模型、WRF-CMAQ模型和BenMAP-CE模型,量化评估了惠州市能源政策和大气污染控制措施对二氧化碳和大气污染物排放、空气质量和人群健康的影响.结果表明, 不实施碳达峰的基准情景下惠州市CO2排放将持续增长,而能源转型能使惠州市在2030年实现碳达峰值6906万t目标,碳减排贡献最大是 电力部门;大气污染末端控制措施叠加能源政策可从源头进一步减少SO2、VOCs、NOx、PM2.5的排放,较基准年2019分别减排4695、44142、38422、12493 t.能源转型情景下惠州市2035年PM2.5年均浓度可以从基准情景的18.25 μg·m-3下降至14.95 μg·m-3,小于世界卫生组织过渡期 第3阶段目标(15 μg·m-3),O3年均浓度也可大幅降低至133.68 μg·m-3;进而得到归因于PM2.5和O3的可避免早逝人数分别为448例(95% CI:143~737)和36例(95% CI:11~61),相对于基准情景获得的人群健康效益为37.88亿元(95% CI:12.37~61.56).  相似文献   
148.
基于2016年河南省农村污染物排放清单,采用县级优化模型,设置了基准和散煤治理2种情景,评估了2025年1月份河南省农村散煤替代的减排潜力,利用空气质量模型(WRF-CMAQ)模拟其对PM2.5污染改善的贡献,并采取泊松回归模型分析了相应的居民健康效益.结果表明,由于围护结构改造的成本较低及保温效果显著,其与采暖设备的组合技术在河南省农村家庭是最适合推广的采暖技术.在散煤治理情景下,2025年1月河南省农村居民燃烧源的SO2,NOx,CO,PM10,PM2.5,VOCs,NH3排放量与基准情景相比分别下降了98.3%,82.6%,99.8%,99.2%,98.8%,98.2%和99.4%.散煤治理情景下河南省2025年1月PM2.5浓度模拟结果与基准情景相比下降4.1μg/m3,可以避免2220人过早死亡,带来23.5亿元经济效益.  相似文献   
149.
淮南矿区高矿化度矿井水淡化工艺实例   总被引:2,自引:0,他引:2  
为充分利用水资源,提高矿井水回用率,淮南矿区谢桥煤矿对高矿化度矿井水进行淡化处理。根据现场运行数据、现场试验,简述了高矿化度矿井水应用反渗透(RO)工艺过程和淡化技术要领。工程运行结果表明:反渗透工艺在煤矿高矿化度矿井水淡化处理中产生了良好的经济、社会和环境效益。  相似文献   
150.
目前对于企业环境经济效益的分析评价,缺乏科学易行的方法。本文根据污染物排放量与经济效益间的关系,提出了单位等标污染负荷利税法,即每排放单位等标污染物所产生的年利税值。据此对四川省6个行业44家企业的环境经济效益进行了统计分析,并对其应用Excel模糊聚类进行了分级评价。结果表明:不同企业间单位等标污染负荷利税值存在多个数量级差异。造纸、纺织企业环境经济效益最差,体现了行业性弊病。制药、建材、机械电子行业企业环境经济效益整体较好,但仍有部分"粗放型"企业环境经济效益差。部分机械电子、化工企业依赖技术革新,环境经济效益优良。与定性分析评价方法相比,单位等标污染负荷利税法更能发现"高产值、高污染"下的误区,该法结合应用Excel模糊聚类分析,可简易、客观分析评价不同企业、行业甚至不同经济规模单元间的环境经济效益。  相似文献   
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