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941.
942.
An Empirical Study on Tangible Augmented Reality Learning Space for Design Skill Transfer 总被引:1,自引:0,他引:1
Tangible augmented reality (TAR) technology opens a novel realm which integrates the computer-generated elements into the real word. Its applications into design education have been explored with a limi-tation to this entire area. TAR offers an innovative learning space by merging digital learning materials into the format of media with tools or objects which are direct parts of the physical space. It is therefore conceived that such combination opens new perspectives in teaching and learning. This paper presented and evaluated one TAR system to improve the pedagogical effectiveness of experiential and collaborative learning process in urban design education. The results from the experiments were analyzed under a previously developed theoretical framework, which show that TAR can enhance the design activities in some collaborative work. 相似文献
943.
Effect of tramadol on immune responses and nociceptive thresholds in a rat model of incisional pain
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Yong-min Liu Sheng-mei Zhu Kui-rong Wang Zhi-ying Feng Qing-lian Chen 《浙江大学学报(自然科学英文版)》2008,9(11):895-902
Objective: To evaluate the effects oftramadol on the proinflammatory responses in a rat model of incisional pain by investigating its effects on nociceptive thresholds and serum interleukin-6 (IL-6) and IL-2 levels. Methods: Forty-two male Sprague-Dawley (SD) rats scheduled for plantar incision were randomly divided into 7 groups 01=6 in each group). Rats in Group 1 receiving general anesthesia with no incision were served as control; At 30 min before skin incision, Groups 2-5 were given 5 ml normal saline or 1, 10, and 20 mg/kg tramadol, respectively, intraperitoneally (i.p.); Group 6 received 10 mg/kg tramadol after operation; Group 7 received 10 mg/kg tramadol before incision, followed by 200 μg/kg naloxone after operation. Mechanical allodynia was measured by electronic yon Frey filament to evaluate the nociceptive thresholds 1 h before incision, and 1 h and 2 h after operation. Serum IL-6 and IL-2 levels were measured by enzyme-linked immunosorbent assay (ELISA) 2 h after operation. Results: Mechanical thresholds decreased significantly and serum IL-6 level increased significantly after operation in Group 2 compared with control (P〈0.01), and these changes were reversed respectively by tramadol in a dose-dependent manner (P〈0.05 and P〈0.01, respectively). IL-2 level remained unchanged after operation in Group 2, but decreased in Group 3 (P〈0.05), then gradually returned to the normal level in Groups 4 and 5. The intraperitoneally injected tramadol (10 and 20 mg/kg) produced a potent and dose-dependent antinocicptive effect on the lesioned paw. The antinocicptive effects of tramadol were partially an- tagonized by naloxone (200 μg/kg), suggesting an additional non-opioid mechanism. Conclusion: The results suggest that tramadol could be a good choice for the treatment of pain under the conditions that immunosuppression may be particularly contraindicated. 相似文献
944.
聚己内酯/淀粉共混材料的非等温结晶动力学 总被引:1,自引:0,他引:1
以异氰酸酯(MDI)为相容剂,采用共混挤出技术制备不同含量的聚己内酯与淀粉的共混产物(SPCL),通过X射线衍射及DSC研究SPCL的结晶性质和非等温结晶行为,分别用Ozawa法和Mo法对所得数据进行处理.结果表明:随着淀粉含量的增加,SPCL的结晶程度降低;淀粉在SPCL中起到了成核剂的作用,加快了聚己内酯(PCL)的结晶速度,但对PCL的结晶程度起抑制作用.建模结果表明,Ozawa法适于处理纯PCL的非等温结晶行为,但不适于处理SPCL共混物,而Mo法对PCL和SPCL共混物均适用. 相似文献
945.
Characterization of high-yield performance as affected by genotype and environment in rice
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We characterized yield-relevant characters and their variations over genotypes and environments (locations and years) by examining two rice varieties (9746 and Jinfeng) with high yield potential. 9746 and Jinfeng were planted in two locations of Shanghai, China, during 2005 and 2006. The results show that there was a large variation in grain yield between locations and years. The realization of high yield potential for the two types of rice was closely related to the improved sink size, such as more panicles per square meter or grains per panicle. Stem and leaf biomasses were mainly accumulated from tillering stage to heading stage, and showed slow decline during grain filling. Meanwhile, some photosynthetic characters including net photosynthesis rate (Pn), leaf area index (LAI), specific leaf area (SLA), fluorescence parameter (maximum quantum yield ofPSll, Fv/Fm), chlorophyll content (expressed as SPAD value), as well as nutrient (N, P, K) uptake were also measured to determine their variations over genotypes and environments and their relationships with grain yield. Although there were significant differences between years or locations for most measurements, SLA at tillering and heading stages, Fv/Fm and LAI at heading stage, stem biomass at heading and maturity stages, and leaf nitrogen concentration at tillering and heading stages remained little changed, indicating their pos- sible applications as selectable characters in breeding programs. It was also found that stem nitrogen accumulation at tillering stage is one of the most important and stable traits for high yield formation. 相似文献
946.
针对在冲击载荷下长测试管柱的减震问题,利用行波法建立了减震系统动力学模型,与以往研究模型进行了比较,分析了减震器在冲击载荷下的动力学特性.结果表明:上部测试管柱的变形将增大减震器系统的阻尼系数,同时减小减震器系统的固有频率,从而增强减震效果;测试管柱材料系数和减震器参数比值影响减震效果,比值愈大,减震效果愈好. 相似文献
947.
基于YUV色彩空间线性变换的图像预处理方法 总被引:1,自引:0,他引:1
针对机器人视觉领域对图像进行颜色分割时存在阈值难以选取的问题,以及RoboCup四腿机器人足球赛这一特定环境,通过采集大量图像进行统计分析,指出了其YUV色彩空间利用率低的问题.为此,提出了一种对U和V通道进行线性扩展的图像预处理办法.该方法使信息颜色能在整个YUV色彩空间中得到扩展,进而强化了不同色彩之间的界限.因此能一定程度上降低颜色分类时阈值选取的难度.同时引入的色彩校正表方法,使得机器人实时运算的开销大大降低. 相似文献
948.
回顾了基于回报函数逼近的学徒学习的发展历史,介绍了目前的主要工作,总结了学徒学习的一般方法,讨论了线性和非线性假设条件下的回报函数求解,比较了逆向增强学习(IRL)和边际最大化(MMP)两类逼近方法.基于IRL的学徒学习是一种通过迭代的方法用基回报函数的线性组合来逼近真实回报函数的过程.MMP方法可以看作是一类基于梯度下降的最优化方法.综合采用滤波及将策略函数概率化等方法可以降低对专家演示的最优要求.最后指出了该领域存在的问题,提出了未来的研究方向,如在部分可观察马尔可夫决策过程框架下的学徒学习及对不确定策略的学习等. 相似文献
949.
将Mathematica应用在医用高等数学教学中,培养学生的抽象思维能力、实际应用能力和创新能力,优化教学过程,提高教学质量,为学生今后学习其他专业课打下良好的数学基础。 相似文献
950.
精细化工实验课程教学改革 总被引:1,自引:0,他引:1
阐述了精细化工专业实验的内容设置、教学方式改革及其考核方式。提出了专业实验内容应配合精细化工发展现状,专业实验的教学应突出培养学生的综合素质;考核方式的改革则客观检查了学生需要改进之处,有利于学生积极进行自我完善。 相似文献