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Angle-sensitive and fast photovoltage of silver nanocluster embeded ZnO thin films induced by 1.064-μm pulsed laser 下载免费PDF全文
Silver nanocluster embedded ZnO composite thin film was observed to have an angle-sensitive and fast photovoltaic effect in the angle range from –90o to 90o, its peak value and the polarity varied regularly with the angle of incidence of the 1.064-μ m pulsed Nd:YAG laser radiation onto the ZnO surface. Meanwhile, for each photovoltaic signal, its rising time reached ~2 ns with an open-circuit photovoltage of ~2 ns full width at half-maximum. This angle-sensitive fast photovoltaic effect is expected to put this composite film a candidate for angle-sensitive and fast photodetector. 相似文献
44.
采用激光分子束外延技术,在玻璃衬底上制备了La067Sr033MnO3 (LSMO) 薄膜,X射线衍射测量结果表明在玻璃衬底上生长的LSMO薄膜沿c轴择优取向生长.在外磁场3 T和88, 220, 300 K条件下,LSMO薄膜的磁电阻变化率分别达到-378%, -268%和-607%.实验结果表明,在廉价的玻璃衬底上制备大面积和具有应用价值的锰氧化物薄膜是可行的.
关键词:
锰氧化物薄膜
玻璃衬底
外延生长 相似文献
45.
基于毕奥萨法尔定律计算了中国聚变工程实验堆(CFETR)中心螺线管模型线圈上的磁场、电磁力,采用有限元分析工具ANSYS计算了线圈引线上的Von-Mises应力。基于分析设计对线圈的内应力进行了评定,并进一步研究了大应力区域各种不同类型的应力的分布状况,为后续模型线圈的进一步优化设计和加工制造提供了参考。 相似文献
46.
The Sr content influence on the positive magnetoresistance in La1-xSrxMnO3/Si heterojunctions 下载免费PDF全文
<正>We fabricated La_(1-x)Sr_xMnO_3/Si(LSMO/Si) heterojunctions with different Sr doping concentrations(x = 0.1, 0.2,0.3) in LSMO and studied the Sr content influence on magnetoresistance(MR) ratio.The hetero junctions show positive MR and high sensitivity of MR ratio in a low applied magnetic field.The MR ratio is dependent on Sr content and the low Sr doping in LSMO causes a large positive MR in LSMO/Si junctions.The MR ratio for 0.1 Sr doping in the LSMO/Si heterostructure is 116%in 100 Oe(1 Oe=79.5775 A/m) at 210 K.The mechanism for the positive MR dependence on the doping density is considered to be the competition between the tunneling rate of electrons in e_g~1↑to t_(2g)↓band and that to e_g~2↑band at the interface region of LSMO.The experimental results are in agreement with those observed in La_(0.9)Sr_(0.1)MnO_3/SrNb_(0.01)Ti_(0.99)O_3 p-n junction.The results indicate that choosing low doping concentration to improve the low field sensitivity of the heterojunction devices is a very efficacious method. 相似文献
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Fast photoelectric effects have been observed in MgB2 thin film
fabricated by chemical vapour deposition. The rise time was $\sim $10
ns and the full width at half-maximum was \sim185\,ns for the photovoltaic
pulse when the film was irradiated by a 308\,nm laser pulse of 25\,ns in
duration. X-ray diffraction and the scanning electron microscope revealed
that the film was polycrystalline with preferred c-axis orientation. We
propose that nonequilibrium electron--hole pairs are excited in the grains
and grain boundary regions for MgB2 film under ultraviolet laser and
then the built-in electric field near the grain boundaries separates
carriers, which lead to the appearance of an instant photovoltage. 相似文献
49.
Competition between Radiative Power and Dissipation Power in the Refrigeration Process in Oxide Multifilms 下载免费PDF全文
The maximum refrigeration power dependence on the doping density in the p-BaTiO3/BaTiO3/SrTiO3/BaTiO3/ n-BaTiO3 system and in the p-AlGaAs/AlGaAs/GaAs/AlGaAs/n-AlGaAs system is obtained respectively based on the opto-thermionic refrigeration model. The results show that the maximum refrigeration power in the p-BaTiO3/BaTiO3/SrTiO3/BaTiO3/n-BaTiO3 system increases dramatically with the increase of doping density from 1.0×1018 cm-3 to 5.0×1019 cm-3 while that in the p-AlGaAs/AlGaAs/GaAs/AlGaAs/n-AlGaAs system is nearly a constant. It is found that the different Auger coefficients and the competition between radiative power and dissipation power lead to the different behavior of the maximum refrigeration power dependence on the doping density of the two systems. 相似文献
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