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971.
In∶Nd∶LiNbO3晶体倍频性能的研究 总被引:1,自引:1,他引:0
在 LiNbO3中掺进In2O3和Nd2O3, 以Czochralski技术生长了In∶Nd∶LiNO3晶体. 通过光斑畸变法测得In∶Nd∶LiNbO3晶体的光损伤阈值为1.98×104 W/cm2, 比Nd∶LiNbO3晶体的1.6×102 W/cm2高两个数量级以上;晶体吸收光谱的测试表明, In∶Nd∶LiNbO3晶体的吸收边相对Nd∶LiNbO3晶体发生紫移. 研究了In∶Nd∶LiNbO3晶体的倍频性能, 结果表明, In∶Nd∶LiNbO3晶体的相位匹配温度在室温附近, 倍频转换效率比Nd∶LiNbO3晶体提高二倍. 相似文献
972.
高功率Cr,Tm,Ho∶YAG激光器的实验研究 总被引:1,自引:0,他引:1
在医学应用上,Cr,Tm,Ho∶YAG激光器需要在大功率、高重频下工作。合理的设计对提高Cr,Tm,Ho∶YAG激光器的输出功率是很重要的。通过对Cr,Tm,Ho∶YAG输出特性进行理论分析和实验验证可知,腔长、全反射镜曲率半径、输出镜透过率、水温等因素对Cr,Tm,Ho∶YAG激光器的输出功率均有影响。提出了优化设计Cr,Tm,Ho∶YAG激光器的方法。在镀银腔情况下,当重频为10Hz时,激光阈值为45J,斜效率为1.1%;当输入能量为121J时,输出的平均功率为9.7W。在陶瓷聚光腔情况下,当重频为10Hz时,激光阈值为40J,斜效率为2.7%;当输入能量为100J时,输出的平均功率为16.2W。 相似文献
973.
激光二极管直接耦合泵浦的高效率Nd:YVO4/KTP腔内倍频激光器 总被引:4,自引:0,他引:4
使激光二极管的发光光面紧贴Nd:YVO4激光晶体,“面对面”直接耦合泵浦,采用KTP晶体腔内倍频,在503mW的泵浦功率下,获得532nm基横模绿光输出约73mW,光光总体转换效率为14.5%。 相似文献
974.
975.
D. Birkedal K. El Sayed G. Sanders C. Spiegelberg V.G. Lyssenko C. Stanton J.M. Hvam V.B. Timofeev M. Bayer 《Superlattices and Microstructures》1997,21(4):587-590
The formation of spatially indirect excitons in superlattices with narrow minibands is investigated experimentally. The interwell exciton is similar to the first Wannier–Stark localized exciton of an electrically biased superlattice. However, in the present case the localization is mediated by the Coulomb interaction of the electron and the hole without external fields. 相似文献
976.
977.
Pierluigi Bruzzone 《Physica C: Superconductivity and its Applications》1998,310(1-4):240-246
The cable-in-conduit superconductors are preferred for applications where the AC losses and stability are a major concern, e.g., fusion magnets and SMES. A review of coupling currents loss results for both NbTi and Nb3Sn cable-in-conduit conductors (CICC) is presented and the AC loss relevant features are listed, with special emphasis for the role of the interstrand resistance and strand coating. The transient stability approach for CICCs is discussed and the analytical models are quoted as well as the relevant experimental database. The likely spectrum of transient disturbance in CICC is reviewed and the need to account for interstrand current sharing in the design is outlined. Eventually a practical criterion for the interstrand resistance is proposed to link the stability and AC loss design. 相似文献
978.
L.E. Vorobjev S.N. Danilov E.A. Zibik D.A. Firsov V.A. Shalygin A.Ya. Shik I.I. Saidashev V.Ya. Aleshkin O.A. Kuznetsov L.K. Orlov 《Superlattices and Microstructures》1997,22(4):467-473
New electro-optical phenomena in quantum-well structures, i.e. modulation of the light absorption and birefringence due to carrier heating in a strong electric field, have been investigated. The effects have revealed different features in the three types of structures under investigation, namely: (1) well-dopedn-type GaAs/AlGaAs multiple quantum wells, (2) barrier-dopedn-type GaAs/AlGaAs superlattices and (3) barrier-dopedp-type Ge/GeSi multiple quantum wells. Possible mechanisms of the phenomena have been discussed. 相似文献
979.
Pawel Pohl Anna Lesniewicz Wieslaw Zyrnicki 《International journal of environmental analytical chemistry》2013,93(11):963-970
Hydride generation inductively coupled plasma atomic emission spectrometry (HG-ICP-AES) in the system with aerosolised sample introduction has been employed for the first time for analysis of conifer needles. Arsenic, bismuth, antimony and tin along with other trace elements were simultaneously determined in pine, spruce, yew and thuja foliage sampled from various locations in Poland and Norway. Quality of the measurements was assured by examination of two attested plant reference materials. The application of different analyte introduction techniques and interference effects from matrix elements, i.e. Na, K, Mg, Ca and transition metals in the analysis of needles are discussed. 相似文献
980.
We have investigated the intrinsic C‐incorporation during the metalorganic vapour‐phase epitaxy of GaAs, (Al,Ga)As, and AlAs. The carbon from the methyl radicals of trimethylgallium and trimethylaluminium has been used as intrinsic carbon source and the necessary growth conditions (low growth temperatures and low V/III‐ratios) have been determined. Under these conditions we observed a reduction of the Al‐incorporation in (Al,Ga)As resulting from a change of surface kinetics at low temperatures. We have used the tensile tetragonal lattice distortion due to the C‐incorporation for determination of the carbon concentration. This has been done by investigating the symmetric (004) reflection peaks of GaAs and the strained epitaxial layer by high resolution x‐ray diffraction. The resulting carbon concentrations showed a good agreement with the hole concentrations determined by Hall measurements and spectroscopic ellipsometry. 相似文献