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51.
联合卡尔曼滤波及其在综合惯性导航系统初始标定中的应用 总被引:3,自引:1,他引:2
本文针对由INS及ESGM 组成的综合惯性导航系统的特点,设计了该系统标校阶段的
联合卡尔曼滤波器。文中给出了该联合卡尔曼滤波器的结构及其算法,该算法具有计算量少、
数据传输量小的优点。理论分析及仿真结果表明该联合卡尔曼滤波算法具有全局最优性,能够
满足系统的标定精度要求,且应用该联合滤波器可大大提高系统的容错性。 相似文献
52.
Active osmium cluster catalysts (derived from Os3(CO)12, H2Os3(CO)10, H4Os4(CO)12, Os6(CO)18 and H2Os10C(CO)24 supported on silica, alumina, titania, and ceria) contain, in their infrared spectra, a band in the region 1930–1985 cm−1 that is characteristic of the cluster/support combination. The activities of these catalysts for reactions of hydrogen with
ethene, carbon monoxide, carbon dioxide, and ethane, relate to their characteristic CO stretching frequencies, giving ‘volcano’
curves. Evidence from ethene hydrogenation kinetics confirms that the characteristic CO-frequency is a monitor of strength
of adsorption at the catalytically active site.
Dedicated to Professor Pál Tétényi on the occasion of his 70th birthday 相似文献
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54.
阐述了利用倍频腔束团长度监测器测量北京正负电子对撞机二期工程电子直线加速器束团长度的原理,通过两个月的测试和数据采集,测得的束团长度集中在1.4~2.0 mm之间,与理论值1.5 mm基本相符。根据不同时刻的记录,基频腔峰值电压与束流流强探测器BCT3所测流强值近似成正比关系;当大幅改变预聚束器和聚束器参数而束流流强不变时,反映聚束质量的五倍频腔信号也随之大幅改变,而反映流强信号的基频腔信号则变化不大,这些试验结果与理论分析完全一致。 相似文献
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为了抑制激光在线测厚时入射角波动引起的误差,根据几何光学分析了激光透射式和反射式测厚原理,发现激光在特定入射角附近波动时,两种方式的测厚误差一正一负,具有互补性,在此基础上提出基于透射和反射同时测量的互补式测厚方法,该方法可将误差限定在透射式和反射式测量误差之间,抑制在线测厚误差.对于有机玻璃平板,理论计算表明,当激光入射角在67.013°±4°波动时,相对误差绝对值在1%以内,误差抑制率均值大于90%;当入射角为61.536°时,误差抑制率为100%.利用线结构激光器和两个线阵CCD相机搭建互补式测厚实验系统,测量了标称厚度为1~5mm的有机玻璃平板,与透射式和反射式测厚结果进行对照,除厚度为1mm的玻璃外,互补式测厚误差被限制在透射式和反射式之间,最大误差抑制率达61%.实验结果表明,该互补式方法有效抑制了误差,提高了在线厚度测量准确度,解决了在线测量不可重复性导致的无法通过均值法减小误差的问题. 相似文献
56.
Beam experiments with a non-intercepting beam induced f luorescence profile monitor for the ADS LINAC
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XIE Hong-Ming WU Jun-Xia ZHANG Yong ZHU Guang-Yu XIA Jia-Wen YE Min-You 《中国物理C(英文版)》2015,39(11):117004-117004
An accelerator-driven subcritical system(ADS) project was launched in China in 2011, aiming to design and build an ADS demonstration facility with the capability of more than 1000 MW thermal power. The driver linac is defined to be a 10 m A current of high energy protons at 1.5 Ge V in continuous wave operation mode. To meet the extremely high power and intense beam accelerator requirements, non-interceptive monitors for the beam transverse profile are required for this proton linac. Taking advantage of the residual gas as active material, the Beam Induced Fluorescence(BIF) monitor exploits gas-excited fluorescence in the visible spectrum region for transverse profile measurements. The advantages of this non-intercepting method are that nothing is installed in the vacuum pipe,component design is compact and there is no need for expensive signal processing electronics. Beam experiments have been performed under constant beam conditions. The helium spectrum has been verified with different optical filters, showing that a proper optical band-pass filter covering 400–500 nm is necessary for fluorescence experiments with helium. By changing gas pressure, it is shown that gas pressure is proportional to the signal amplitude but has no influence on detected profile width. Finally, a comparison experiment between the BIF monitor and a wire scanner shows that the detected profile width results of both methods agree well. 相似文献
57.
Effect of current density on the microstructure and corrosion behaviour of plasma electrolytic oxidation treated AM50 magnesium alloy 总被引:1,自引:0,他引:1
P. Bala Srinivasan J. Liang C. Blawert M. Störmer W. Dietzel 《Applied Surface Science》2009,255(7):4212-4218
Plasma electrolytic oxidation (PEO) of an AM50 magnesium alloy was accomplished in a silicate-based electrolyte using a DC power source. Coatings were produced at three current densities, i.e. 15 mA cm−2, 75 mA cm−2, and 150 mA cm−2 and were characterised for thickness, roughness, microstructural morphology, phase composition, and corrosion resistance. Even though the 15 min treated coatings produced at higher current density levels were thicker, they showed poor corrosion resistance when compared to that of the coatings obtained at 15 mA cm−2. Short-term treatments (2 min and 5 min) at 150 mA cm−2 yielded coatings of thickness and corrosion resistance comparable to that of the low current density coatings. The superior corrosion resistance of the low thickness coatings is attributed to the better pore morphology and compactness of the layer. 相似文献
58.
激光监听实验的开设与研究 总被引:1,自引:0,他引:1
本文介绍了综合、设计性实验——激光监听实验的开设过程,以及对影响实验效果若干因素的研究。 相似文献
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