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621.
Objective: The objective of this study was to estimate the effect of the Brazilian zero-tolerance drinking and driving law on mortality rates due to road traffic accidents according to the type of victim, sex, and age.

Methods: An interrupted time series design was used to compare yearly mortality rates due to road traffic accidents in Rio de Janeiro, Brazil, before and after the zero-tolerance drinking and driving law came into effect on June 19, 2008. Yearly mortality rates were compared according to the type of victim: pedestrian, cyclist, motorcyclist, and vehicle occupant. We used the Prais-Winsten procedure of autoregression in the analysis of time series; the outcome of this analysis was the annual percentage change in the rates. Overall and stratified analyses were conducted to investigate whether the zero-tolerance drinking and driving law may have had a distributional effect on mortality rates due to road traffic accidents depending on sex and age group; a significance level of P < .01 was accepted.

Results: From 1999 to 2016, there were 15,629 deaths due to road traffic accidents in Rio de Janeiro. The effect of the zero-tolerance drinking and driving law on overall mortality rates due to road traffic accidents in Rio de Janeiro was not statistically significant. However, among cyclists and motorcyclists aged ≥60 years and among pedestrians of both sexes and aged ≥20 years, the effect of the zero-tolerance drinking and driving law was to decrease mortality due to road traffic accidents at a yearly rate.

Conclusion: There is evidence of reduced mortality rates due to road traffic accidents among cyclists and motorcyclists aged ≥60 years and among pedestrians of both sexes aged ≥20 years in the second major Brazilian capital 9 years after the zero-tolerance drinking and driving law was adopted.  相似文献   

622.
核与辐射安全监管现代化是国家治理体系和治理能力现代化建设的重要组成部分,而实现我国核与辐射安全监管现代化就是要不断推进我国核与辐射安全监管体系和监管能力现代化进程。当前,作为我国核与辐射安全监管能力之一的监督执法能力,其重要性愈来愈突出,如何促进监督执法能力建设这一现实问题已经引起了社会的普遍关注。从我国核与辐射安全监督执法能力的理论基础出发,总结了近年来我国核与辐射安全监督执法能力建设的主要做法以及取得的成效,最后指出存在的不足。  相似文献   
623.
百年工业文明发展范式对自然环境的持续作用,使人类面临环境与发展的双重危机。生态文明具有内在统一性,环境法制是生态文明的应有之义。环境基本法是环境法制的基石,目的条款是环境基本法的元点。旧的目的条款沿袭工业文明发展范式,将发展经济奉为圭臬,始终无法调和人与自然的内在矛盾。修改环境基本法目的条款,融入生态文明因子具有自内而外、自外而内、自上而下以及自下而上四个方面的动力因素。  相似文献   
624.
传统村落在历史、文化、经济、旅游和科学等多个方面价值颇高,保护传统村落的空间格局和文化内涵极为重要。以中国湘江流域上中下游六个典型传统村落为例,以景观基因理论为基础,运用景观基因分析法识别了湘江流域传统村落景观基因,分析了上中下游传统村落显性物质景观基因与隐性非物质文化基因的变异特征,总结了湘江流域传统村落景观基因变异特征及分异规律,研究结果显示:(1)湘江流域上游传统村落平面基因变异相悖于本土的情况侧重发生在平面结构变异上;立面基因的变异相悖于本土、突变后直接消亡的情况较多;文化基因上受外来冲击的不适感较强,有加剧景观基因变异的风险和趋势。(2)湘江流域中游传统村落对立面基因的改动需求较大,且改动时间较早,造成立面基因变异以及平面基因中街巷格局、平面布局变异较大,变异后相悖于本土的特征显著;而在文化基因中,对文化的变异融合接受能力强,变异相融于本土的情况显著。(3)湘江流域下游传统村落在形态、布局特征明显的平面基因中产生的变异不大显著;在立面基因中遭遇突变后直接消亡的特征明显;在文化基因中,对家风信仰的基因变异以相融于本土为主,习俗礼仪的基因变异呈现分化趋势,单民族聚居式的家族以相悖于本土的特征为主,多民族聚居式的家族以相融于本土的特征为主。  相似文献   
625.
添加邻苯二甲酸酯(PAEs)增塑剂的塑料管道被广泛用于自来水管道系统,存在健康风险.然而,塑料管道是否是自来水中PAEs的污染来源仍了解不足.因此,本文探究了两种常用管材—硬质聚氯乙烯(UPVC)、聚丙烯(PPR)的新管道和人为磨损管道,在不同水力停留时间和余氯浓度下向水样中释放PAEs的规律.结果表明,人为磨损会使管道中PAEs向自来水中的总释放量增多,其中,邻苯二甲酸二丁酯(DBP)最为明显,且人为磨损管道释放PAEs的速率大于新管道.对于不同管材的管道,PPR管道PAEs的释放量小于UPVC管道,因而针对PAEs污染,PPR管道可能比UPVC管道更安全.在所有实验中,添加余氯可使水中PAEs浓度整体更低,且余氯浓度越高,平衡时的PAEs浓度越低,因而 推测PAEs可能会与余氯发生化学反应.本研究揭示了塑料管道作为自来水中PAEs的来源之一,向水体中释放PAEs的规律及影响因素,从而为自来水水质安全的控制提供了新的关注点.  相似文献   
626.
《中华人民共和国反食品浪费法》(以下简称《反食品浪费法》)的颁布实施,使长期以来中国反对食物浪费实现了由道德约束到法制治理的历史性转变。该法律是在当今世界食物浪费现象普遍、威胁全球粮食安全和中国政府高度重视食物浪费问题的背景下颁布的,意义重大。这部法律为中国反食物浪费社会实践提供了法律保证,也为全球反食物浪费事业提出了中国答案。《反食品浪费法》具有注重顶层设计、立法过程快捷简明,立法目的鲜明、节约资源融贯始终,法律措施全面、规制责任主体广泛,社会多元共治、凸显节粮治理效能,依法施策、致力于服务粮食安全战略,坚持德法并举、推动节粮意识转为法律约束等显著特点。从一年来的实践看,《反食品浪费法》在实施中,目前仍需解决进一步厘清权责、细化标准体系和加强基础支撑等关键问题,有关部门应着重通过采取建立长效监测评估机制、构建科学有效的监测评估方法体系和加强相关部门协同联动等措施,规范和指导《反食品浪费法》落地实施,充分发挥其规制和规范全社会各种各样食物浪费行为的作用,有效减少食物浪费,保障国家粮食安全,助推生态文明和社会文明建设。  相似文献   
627.
航空安全一直以来备受社会各界关注,其中安全间隔对于航路运行有非常重要的意义。为了合理分配航路间隔,减少航路拥堵,基于实际运行情况,将连续的飞机流作为研究目标,从宏观和微观角度建立了纵向间隔的计算模型,根据飞机流的跟驰效应,得出航路运行间隔的动态变化范围。在此基础上,提出了快速地对航空器进行间隔调整的方案。最后,以西安管制区的运行数据为例进行仿真,验证了模型的合理性,并分析了各因素对飞行流间隔的影响,调整方案可以较快地完成航路间隔的重新分配,为运行提供更准确的引导。  相似文献   
628.
Anthropogenic land‐cover change is driving biodiversity loss worldwide. At the epicenter of this crisis lies Southeast Asia, where biodiversity‐rich forests are being converted to oil‐palm monocultures. As demand for palm oil increases, there is an urgent need to find strategies that maintain biodiversity in plantations. Previous studies found that retaining forest patches within plantations benefited some terrestrial taxa but not others. However, no study has focused on aquatic taxa such as fishes, despite their importance to human well‐being. We assessed the efficacy of forested riparian reserves in conserving freshwater fish biodiversity in oil‐palm monoculture by sampling stream fish communities in an oil‐palm plantation in Central Kalimantan, Indonesia. Forested riparian reserves maintained preconversion local fish species richness and functional diversity. In contrast, local and total species richness, biomass, and functional diversity declined markedly in streams without riparian reserves. Mechanistically, riparian reserves appeared to increase local species richness by increasing leaf litter cover and maintaining coarse substrate. The loss of fishes specializing in leaf litter and coarse substrate decreased functional diversity and altered community composition in oil‐palm plantation streams that lacked riparian reserves. Thus, a land‐sharing strategy that incorporates the retention of forested riparian reserves may maintain the ecological integrity of fish communities in oil‐palm plantations. We urge policy makers and growers to make retention of riparian reserves in oil‐palm plantations standard practice, and we encourage palm‐oil purchasers to source only palm oil from plantations that employ this practice.  相似文献   
629.
Vidon, Philippe, Craig Allan, Douglas Burns, Tim P. Duval, Noel Gurwick, Shreeram Inamdar, Richard Lowrance, Judy Okay, Durelle Scott, and Steve Sebestyen, 2010. Hot Spots and Hot Moments in Riparian Zones: Potential for Improved Water Quality Management. Journal of the American Water Resources Association (JAWRA) 46(2):278-298. DOI: 10.1111/j.1752-1688.2010.00420.x Abstract: Biogeochemical and hydrological processes in riparian zones regulate contaminant movement to receiving waters and often mitigate the impact of upland sources of contaminants on water quality. These heterogeneous processes have recently been conceptualized as “hot spots and moments” of retention, degradation, or production. Nevertheless, studies investigating the importance of hot phenomena (spots and moments) in riparian zones have thus far largely focused on nitrogen (N) despite compelling evidence that a variety of elements, chemicals, and particulate contaminant cycles are subject to the influence of both biogeochemical and transport hot spots and moments. In addition to N, this review summarizes current knowledge for phosphorus, organic matter, pesticides, and mercury across riparian zones, identifies variables controlling the occurrence and magnitude of hot phenomena in riparian zones for these contaminants, and discusses the implications for riparian zone management of recognizing the importance of hot phenomena in annual solute budgets at the watershed scale. Examples are presented to show that biogeochemical process-driven hot spots and moments occur along the stream/riparian zone/upland interface for a wide variety of constituents. A basic understanding of the possible co-occurrence of hot spots and moments for a variety of contaminants in riparian systems will increase our understanding of the influence of riparian zones on water quality and guide management strategies to enhance nutrient or pollutant removal at the landscape scale.  相似文献   
630.
The riparian ecosystem management model (REMM) was field tested using five years (2005‐2009) of measured hydrologic and water quality data on a riparian buffer located in the Tar‐Pamlico River Basin, North Carolina. The buffer site received NO3‐N loading from an agricultural field that was fertilized with inorganic fertilizer. Field results showed the buffer reduced groundwater NO3‐N concentration moving to the stream over a five‐year period. REMM was calibrated hydrologically using daily field‐measured water table depths (WTDs), and with monthly NO3‐N concentrations in groundwater wells. Results showed simulated WTDs and NO3‐N concentrations in good agreement with measured values. The mean absolute error and Willmott's index of agreement for WTDs varied from 13‐45 cm and 0.72‐0.92, respectively, while the root mean square error and Willmott's index of agreement for NO3‐N concentrations ranged from 1.04‐5.92 mg/l and 0.1‐0.86, respectively, over the five‐year period. REMM predicted plant nitrogen (N) uptake and denitrification were within ranges reported in other riparian buffer field studies. The calibrated and validated REMM was used to simulate 33 years of buffer performance at the site. Results showed that on average the buffer reduced NO3‐N concentrations from 12 mg/l at the field edge to 0.7 mg/l at the stream edge over the simulation period, while the total N and NO3‐N load reductions from the field edge to the stream were 77 and 82%, respectively.  相似文献   
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