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881.
The recovery potential for waste energy from major Chinese industries is significant. For example, the estimated waste energy recovery potential is 40 million tons of coal equivalent in the iron and steel industry, accounting for ~10% of the total energy use in the industry. A detailed overview is presented of existing waste energy recovery Clean Development Mechanism (CDM) projects in China. These projects have been developed predominantly in large enterprises and rarely in small or medium-sized companies. The chance of waste energy projects being reviewed or rejected by the Executive Board is slightly higher and delivery rates of certified emission reductions are generally lower than other types of CDM projects. Several major barriers that inhibit project development are identified, such as the lack of CDM awareness or development capacity among many small or medium enterprises, low internal rates of return of the projects, increasing review risk and long delays in the registration process, the varying quality of intermediary buyers, a lack of local Chinese Designated Operational Entities, and policy implementation inconsistency at different levels. Suggestions are put forward to address these problems and such critical issues as additionality are also discussed. 相似文献
882.
Gradon Diprose Kelly Dombroski Emma Sharp Amanda Yates Bailey Peryman Martine Barnes 《New Zealand geographer》2023,79(1):15-26
Aotearoa New Zealand is at a critical juncture in reducing and managing organic waste. Research has highlighted the significant proportion of organic waste sent to landfills and associated adverse effects such as greenhouse gas emissions and loss of valuable organic matter. There is current debate about what practices and infrastructure to invest in to better manage and use organic waste. We highlight the diversity of existing organic waste practices and infrastructures, focusing on Auckland, Wellington and Christchurch. We show how debates about organic waste practices and infrastructure connect across three themes: waste subjectivities, collective action in place and language. 相似文献
883.
884.
核素在裂隙介质中的迁移问题是核废物深地质处置中极为关注的问题。为了解裂隙介质中核素的迁移规律,建立了基于双重介质理论的描述核素在裂隙域和基质域中迁移的基本微分方程,利用拉普拉斯变换推导出其解析解;在对西北某核废物处置场预选区地水文地质条件分析的基础上,获取相关参数,利用一维多途径核素迁移模型,选取国内在花岗岩中研究较多的核素Cs-134、Co-57、Tc-99,模拟这几种核素的相对浓度随模拟时间、迁移距离的变化规律。模拟结果表明:在其他条件都相同的情况下,Cs-134的迁移是最快的,而Tc-99迁移是最慢的。 相似文献
885.
膨润土缓冲材料热传导特性的研究,对于高放废物深地质处置系统的安全评价至关重要。基于串、并联原理,通过将土体孔隙划分为与固相基质并联和串联两部分,提出了考虑矿物成分、颗粒亲水性、孔隙率及饱和度等因素的非饱和膨润土有效热传导系数的4种预测形式,建立了基于4种形式线性组合的有效热传导特性预测模型。详细讨论了模型参数的确定方法,并讨论了孔隙率、饱和度和孔隙结构、颗粒亲水性等因素对土体有效热传导特性的影响。基于MX-80膨润土和高庙子膨润土热传导特性试验成果,对模型的预测性能进行了验证。结果表明,由于膨润土颗粒尺寸较小且具有亲水特性,孔隙内的空气与水宜采用并联描述。研究成果对于非饱和膨润土的导热性能以及工程屏障系统的THM耦合数值模拟研究具有一定的参考价值。 相似文献
886.
Elsheikh RAGAB 《《地质学报》英文版》2014,88(Z1):363-365
正1 Introduction The left-over(residual)brines often in industrial facilities is disposed back to the sea or in dump areas e.g.abundant salt mines in other cases.Dumping into the sea 相似文献
887.
《Geoforum》2017
International trade of discarded electronics (e-waste) has become a matter of concern over the last decade because of the actual and potential harms associated with their hazardous materials. An initiative under the aegis of the UN called the Best-of-Two-Worlds (Bo2W) philosophy is one solution to the e-waste problem that has gained some traction. Our dual purpose is to examine the ethical grounds of Bo2W and to propose an alternative program for action. We call this alternative ethical electronics repair, reuse, repurposing, and recycling (EER4). To explore the ethical grounds of Bo2W and to articulate EER4 as an alternative, we draw on notions of ethics, technology, and organization developed in science and technology studies (STS) and diverse economies literatures while empirically we explore a mixed methods case study of a small recycling firm in northern Mexico. Conceptually and empirically, our analysis points to a need for a richer imagination of the possibilities for economic action oriented toward managing discarded electronics. More broadly, our findings may act as a reminder that the space between use and discard proliferates the literal and figurative resources for enriching the imagination and enactment of diverse economic possibilities via the action of repair, reuse, repurposing, and recycling. 相似文献
888.
Wooseok Bae 《Marine Georesources & Geotechnology》2017,35(2):216-225
The large amount of wastes is generated in metropolitan area where population is heavily concentrated. As a result, treatment of wastes became a social problem and geotechnical problems related to landfill have emerged in Korea. Settlement behavior of waste landfill is similar to behavior of peat that possesses relatively small time-dependent secondary compression alongside large initial compression. A number of researchers published their own settlement computations. However, accurate computation method for waste-reclaimed landfill has yet to be determined as the settlement mechanism is very complicated. Hence, it is important to examine the accurate settlement behavior of reclaimed ground by comparing the material properties from laboratory test and field monitoring and comparing the results with the theoretical equation. This study determines the consolidation coefficients according to the change of organic contents through the total volume reduction in fresh waste layer and initial void ratio change and examines the feature of settlement in each load stage. Moreover, the article attempts to investigate the characteristics of consolidation of the relevant reclaimed landfill and to determine the suitability of the equation by comparing the variables in theoretical equations obtained from the laboratory test and field monitoring. Moreover, to verify the compression characteristics of the waste-reclaimed landfill upon loading, consolidation test results were analyzed to conduct index study on the consolidation characteristics of the waste-reclaimed landfill. 相似文献
889.
为研究加筋土挡墙在墙顶荷载作用下土体受力和变形形态,通过改变筋材层数、筋材长度和替换加筋材料等方式对加筋土挡墙进行了4种工况的模型试验。对4种工况下的加筋土墙体内竖向土压力、墙面水平位移、墙顶竖向位移和筋材应变等进行对比研究。研究表明,挡墙上部竖向土压力增长较快且各层竖向土压力最大值由加载点下部向墙面处移动;墙顶荷载超过130 kPa时,由于不均匀沉降,第5层筋材对应墙面处有向内收缩趋势,墙面水平位移最大值大约在上三分点位置;整个加载阶段,筋材总体应变值增幅不大且远小于筋材设计应变峰值;增加挡墙内筋材层数和增加筋材长度均可提升挡墙各方面性能,但增加筋材层数提高效果要优于增加筋材长度;使用废旧轮胎代替单向格栅进行加筋可有效提高挡墙整体性能,分散超载引起的附加应力,有效减小墙面水平位移和墙顶竖向位移。 相似文献
890.
作为高放废物处置罐候选金属材料,低碳钢在处置库服役期间,其腐蚀产物侵入缓冲屏障,导致缓冲材料矿物相变与性能变异,威胁多重屏障体系的长期安全稳定。本文详细综述了国内外处置库深部还原环境所处的弱碱性化学场与中低温度场的变化趋势,认为处置库深部化学-温度还原条件可导致处置罐Fe腐蚀释放Fe~(2+)。在处置库长期运行过程中,蒙脱石与Fe~(2+)接触发生矿物相变,一方面Fe~(2+)置换蒙脱石八面体晶格中的Al~(3+)和Mg~(2+),还原Fe~(3+)或直接占据空位,生成次生矿物;另一方面Fe~(2+)交换蒙脱石层间的Na~+、K~+和Ca~(2+),转化为铁基蒙脱石。矿物相变可诱发缓冲屏障性能变异甚至退化。基于"抗矿物转化"理念,提出了下一阶段缓冲材料矿物相变研究方向,为地下实验室碳素钢选型、缓冲屏障验证试验设计以及屏障体系安全评价提供科学依据。 相似文献