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151.
The need to produce an ever-increasing quantity of material products and food resulting from the planet globalization process has contributed to the spread of modern agriculture based on a linear production resulting in the generation of tons of waste. This huge amount of waste is generally accumulated in landfills, causing different environmental problems. Hence, researchers moved on to study the processes used to recover agro-industrial by-products within a circular and sustainable bio-economy concept. A systematic quest on Scopus and PubMed databases was performed to identify the data available to date on recycling agro-industrial by-products of Olea europaea L. This systematic review summarizes the knowledge regarding the use of olive trees by-products for producing animal feed, biocomposites, bioethanol, cellulose pulp, activated carbon, and as a fuel source for energy production. Furthermore, the data regarding the potential biological activity of extracts from olive roots, wood, bark, and pruning were analyzed. Olive trees by-products are, indeed, rich in molecules with antioxidant, antimicrobial, cardioprotective, and anticancer activity, representing a promising candidate for treat several human diseases.  相似文献   
152.
投入要素可以分为有形资源、无形资源和人力资源,进一步可以将无形资源分为信息资源、技术进步、制度与管理因素.文章以江苏省为例,采用鸿沟系数及面板数据分析了要素投入差距与经济发展水平差距之间的关系,认为江苏省经济发展水平的地区差距正在缓慢拉大,资本投入的地区差距拉大是主要原因,技术进步的地区差距轻微拉大对经济发展水平差距拉大的作用较小,劳动力投入的地区差距对经济发展水平差距没有影响,而信息资源投入的地区差距缩小对经济发展水平地区差距缩小有显著的贡献.  相似文献   
153.
宋怡  纪慧 《化学教育》2017,38(23):58-61
以美国军事教育拓展项目AEOP举办的Ecyber Mission科学竞赛为例,介绍其在非正式STEM教育方面的有益尝试。相较于正式STEM教育,Ecyber Mission科学竞赛更具开放性、综合性与实践性。通过对其参与人员、主题领域设置、组织实施形式和获奖案例进行分析,以期对我国STEM教育在非正式教育中的拓展有所启发。  相似文献   
154.
为了进一步测度评价对象整体的变化速度发展态势,结合已有关于评价对象静态评价模型、变化速度状态和趋势测量模型的研究,以信息集结视角和“激励与惩罚”手段,运用变化速度趋势对变化速度状态进行修正,构建了融合变化速度状态和趋势等变化速度特征的变化速度动态综合评价模型。并以我国30个省区作为样本进行实证研究,得出各省区2005年~2011年间知识密集型制造业技术创新能力截面静态和变化速度动态综合评价结果,结果表明:知识密集型制造业技术创新能力较高的东部发达省份,其变化速度上升趋势微弱,甚至不少省份呈现递减状态;而知识密集型制造业技术创新能力较低的中西部省份,多数地区变化速度上升趋势显著,且上升趋势幅度高于多数东部省区。  相似文献   
155.
The efficiency becomes a key issue in today's natural product total synthesis. While biomimetic synthesis is one of the most elegant strategies to achieve synthetic efficiency and thus to approach the ideal synthesis, most biogenetic pathways are unknown or unconfirmed. In this account, we demonstrate, through the shortest and also the most efficient asymmetric total syntheses of the hexacyclic alkaloid (?)‐chaetominine to date, that on the basis of biogenetic thinking, one can develop quite efficient bio‐inspired total synthesis, which in turn serves to suggest and chemically validate plausible biosynthetic routes for the natural product. The synthetic strategy thus developed is also inspiring for the development of other synthetic methods and efficient total synthesis of other natural products.  相似文献   
156.
结合非期望产出的SBM-DEA模型与SFA方法,提出基于非期望产出的三阶段SBM-DEA模型,用于对全要素碳排放效率的测算。该模型具有非径向和非角度的特点,而且能剔除外部环境和随机因素的影响,使效率评价更接近实际情况。运用该模型对2000~2012年我国各区域二氧化碳排放绩效进行了评价与分析。结果表明,全国平均碳排放效率不高,但从2006年呈现加速上升趋势,表现了低碳经济良好的发展态势。剔除外部环境和随机因素影响后的碳减排效率将进一步下降。分区域来看,我国碳排放效率呈现出“东>中>西”的格局,且东部的优势有所扩大。基于对投入、产出冗余以及外部环境因素影响的分析表明,提升能源、资本、人员的配置效率,加强东部地区与中西部地区之间的人才和技术交流,有利于提升碳排放效率。
关键词:碳排放效率;三阶段DEA;SBM模型;SFA回归  相似文献   
157.
应用国家重大区域规划中的典型规划“长江三角洲地区区域规划”中两省一市的经济数据,建立了不同时间窗口的固定效应变截距回归模型。通过对比不同时间窗口模型回归系数的变化,得到国家重大区域规划的政策效果。本研究的创新与特色:一是通过全部三个省份不同时间窗口变截距回归模型斜率系数的变化,得到单位政策变量导致效果变量增量变化的大小。二是通过规划前后全部三个省份不同时间窗口回归方程截距变化的对比,得到效果变量总额增加自发部分的大小。本文的创新点一和二改变了现有研究通过不同区域的横向数据对比获取评价效果的现状;事实上,不同区域由于客观基础和条件的差异是不具备可比性的。三是通过对比规划前后不同省份效果回归函数截距大小排序的变化,判别不同省份之间发展的均衡程度的变化。主要结论:一是规划区域中央固定资产投资的单位投入对城乡居民人均可支配收入的改变量有显著增加;由于经济发展水平的提高中央补助收入的单位投入对城乡居民可支配收入的变化量减少,其影响不再显著。二是规划区城乡居民人均可支配收入自发水平有显著增加。三是长三角规划区各省间人均可支配收入的自发性收入水平的差距缩小。  相似文献   
158.
The recovery of bioactive compounds from agro-industry-derived by-products sustains circular economy principles by encouraging maximized recycling and minimized waste. Tomato processing by-products are abundant in carotenoids, which have several health-promoting properties, and their reintegration into functional food products represents a major interest for scientists and manufacturers. In the present study, carotenoids were recovered from tomato processing by-products based on the principles of green chemistry by using generally recognized as safe (GRAS) solvents, freeze-drying as pretreatment, and ultrasound in the recovery procedure. Spectrophotometric measurements and HPLC were used to identify and quantify total and individual carotenoids from the extracts. The highest values for lycopene (1324.89 µg/g dw) were obtained when ethyl lactate was applied as a solvent, followed by ethyl acetate with slightly smaller differences (1313.54 µg/g dw). The extracts obtained from freeze-dried samples presented significantly lower amounts of lycopene, indicating that carotenoids are highly susceptible to degradation during lyophilization. Flaxseed, grape seed, and hempseed oils were enriched with carotenoids and their rheological measurements showed favorable viscoelastic properties, especially hempseed and flaxseed oil, with viscosity under 50 mPa·s. Considering the results and the economic perspective of carotenoid recovery from tomato processing by-products, ethyl acetate is suitable, sustainable, and environmentally friendly for carotenoid extraction.  相似文献   
159.
Phosphorus raw materials are non-renewable, and their resources are shrinking faster and faster as a result of increased fertilizer production. This is due to the increasing population and the need to produce more food. Phosphorus, on the other hand, is one of the main nutrients of plants, without which it is impossible to conduct intensive agricultural production. There are no economically significant phosphate resources in Europe, so they must be imported. That is why it is so important to reduce losses and recover this element from waste streams, which was reflected in the new EU Regulation 2019/1009. A prospective option is to use waste phosphates from the production of polyether polyols. Previous studies show that they contain about 20% phosphorus. Due to their high water content, the most advantageous form of their application is the production of fertilizers in the form of a suspension. The aim of the study is to assess the possibility of using waste phosphates from the production of polyols as raw materials for the production of suspension fertilizers.  相似文献   
160.
A highly efficient and sustainable approach for the multi-component synthesis of biologically important 3-amino alkylated indoles has been investigated via Mannich-type reaction under catalyst-free, ethylene glycol as a recyclable promoting medium. The wide applicability of the present method was examined with various substrates viz substituted aldehydes, indoles and secondary amines. This method will be useful for a large scale synthesis of 3-amino alkylated indoles without the use of column chromatography. The present method provides higher environmental compatibility and sustainability factors such as smaller E-factor (0.433) and higher atom-economy (AE = 93.3%).  相似文献   
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