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601.
主题公园生命周期的演化 总被引:13,自引:1,他引:13
旅游地生命周期理论向我们描绘了旅游地在发展过程中有规律性的阶段变化,但对于任何一个旅游地来说,其发展演化都有着自己独特的特点.根据旅游地生命周期理论,并结合国际、国内主题公园的实际发展情况,对其演化情况作了具体分析研究,认为主题公园的发展存在双周期模型,并就该模型的各发展阶段提出了一定的发展策略. 相似文献
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603.
合理开发矿产资源,优化资源配置和产品结构,是贫困山区脱贫致富的实现选择,本文以北川县为例,立足市场需求和该县矿产资源,地理,经济等情况,综合分析了有利条件和制约因素,提出了开发北川矿产资源的战略指导思想,目标,重点和主要对策。 相似文献
604.
极值动态新Ⅰ型分布函数的模型及在汕头抗风防灾上的应用 总被引:1,自引:0,他引:1
最大风速分布函数的选择是抗风减灾的重要因素,迄今为止国内外所有可选择的分布函数,虽然对一个国家一些城市是好的,但是对另一些城市却不好,好的城市中,拟合优度准则检验结果也不能达到最佳位或趋近为1.本文采用动态的观点,根据不同城市的数据可用不同的参数值,使其可达到优度最佳值或趋近为1,在此思想基础上,改进了现在国内外绝大多数国家规范所采用的极值Ⅰ型,成为极值动态新Ⅰ型,是对分布函数选择彻底改革的一次尝试。按此原理,对汕头1959~1993共35年最大风速数据进行了分析,对各种概率条件下的风速风压提出了应用的数值。 相似文献
605.
D. Makarov F. Verbecke V. Molkov 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):433-438
This paper presents a model and simulation results for the mitigation of a hydrogen–air deflagration by venting through a duct. A large eddy simulation (LES) model, applied previously to study both closed-vessel, and open atmosphere hydrogen–air deflagrations, was developed further to model a hydrogen–air explosion vented through a duct. Sub-grid scale (SGS) flame wrinkling factors were introduced to model major phenomena which contribute to the increase of flame surface area in vented deflagrations. Simulations were conducted to validate the model against 20% hydrogen–air mixture deflagrations (vent diameters 25 and 45 cm) and 10% hydrogen–air mixture deflagration (vent diameter 25 cm). There was reasonable correlation between the simulations and the experimental data. The comparative importance of different physical phenomena contributing to the flame wrinkling is discussed. 相似文献
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607.
建构和谐社会是可持续发展战略的目标。从可持续发展系统层次结构与旅游区发展的关系出发,以和谐思想为支撑,解析建构环巢湖带过程中的非和谐阻力,提出建构和谐环巢湖旅游带的战略响应原则和战略响应举措,为相关部门积极主动、科学合理地规避规划、开发、经营和管理中来自各方的非和谐阻力,以期为打造一个体现和谐、健康、可持续发展的环巢湖旅游带提供一定的借鉴作用。 相似文献
608.
Due to increasing pressure from the European Union to meet recycling and recovery targets, (e.g. the packaging waste, waste electronic equipment and landfill directives), both the Irish and England's governments’ policy on waste management is changing to meet these pressures, with major emphasis upon the management of biodegradable municipal waste (BMW). In particular, the EU landfill directive requires reductions in the rate of biodegradable waste going to landfill to 35% by 2016. The objective of this paper is to examine how Ireland plans to meet this challenge and to compare the Irish strategy to that being adopted in England. The approach in England is driven by a clear understanding that the practice in the late 1990s was unlikely to ensure compliance with EU targets by the set dates. England has therefore developed a discrete, programme (Waste Implementation Programme) to drive a new approach, based on rigorous science and international best practice, which includes a Demonstrator Programme for new technologies. The dynamic, high cost, large scale programme in England stands in sharp contrast to that for Ireland and only future, detailed analysis of outcomes will be able to evaluate the cost effectiveness of each. 相似文献
609.
邓小平与毛泽东的现代化发展目标是一脉相承的,但邓小平对毛泽东的现代化发展目标又进行了超越,他继承了毛泽东的现代化思想及分步骤进行现代化建设的设想,扩展了现代化的内涵,提出了分“三步”实现现代化的科学构想,从而促进了中国现代化的发展。 相似文献
610.
Many different approaches for national sustainable development strategies (NSDS) have been proposed since 1992, with some components common to all. A country's national strategy should be designed to help mainstream environmental concerns into policy. More broadly, it should coordinate local policy with global concerns, as well as integrate scientific knowledge into policy and development planning. The peer review mechanism for national strategies was piloted by France, and also involved representatives of countries from the North and the South as well as stakeholders. The peer review process allows countries to share their experience and information, and can assist them in identifying their own path to sustainable development. The business community can also contribute to sustainable development through provision of local and global public goods. Another input to sustainable development could come from the International Organization for Standardization (ISO) and its Guidance Standard on Social Responsibility (ISO 26000), as a coordinating mechanism between voluntary initiatives and binding obligations (such as international conventions). ISO standards and guidelines should therefore be integrated with national sustainable development strategies and local Agenda 21 frameworks. 相似文献