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991.
992.
Lihua Wang Jian Zhu Yan Yan Yaning Xie Changsui Wang 《Journal of Raman spectroscopy : JRS》2009,40(8):998-1003
Red and green color porcelain (Honglvcai) is an important type of polychrome porcelains invented in North China during Song and Jin Dynasties. One of its great successes is its red decoration painted on the surface of glaze and fired at low temperature. Raman spectroscopy and X‐ray absorption fine structure (XAFS) at Fe K‐edge, were used to characterize the microstructure of red decorations from Song and Jin Dynasties to Ming Dynasty. The analyzing results on eight samples showed that hematite (α‐Fe2O3) was the main chromogenic substance in red decorations from different dynasties, which indicated a similar technological skill among the investigated samples. The oxidation state of iron in red decorations was determined to be mainly trivalent, indicating that red decorations were fired under oxidizing atmosphere. Besides, it was found that the hematite (α‐Fe2O3) in red decorations had a distorted structure, which was presumed to be an important factor influencing the color of red decorations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
993.
Sadia Ameen S.G. Ansari Minwu Song Young Soon Kim Hyung-Shik Shin 《Superlattices and Microstructures》2009,46(5):745-751
The work reports on the fabrication of a p–n heterojunction structure comprised of polyaniline (PANI) and TiO2 nanoparticles. PANI was deposited by plasma enhanced polymerization on TiO2 thin film substrates. The structural and the crystalline properties demonstrated the coherence and the substantive interaction of the plasma polymerized PANI molecules with the TiO2 nanoparticle thin film. The UV–Vis studies of PANI/TiO2 thin film supported the internalization of PANI with TiO2 nanoparticles due to π–π* transition of the phenyl rings with the lone pair electrons () of the nitrogen atom present in the PANI molecules. The I–V characteristics of the PANI/TiO2 heterojunction structure were obtained in the forward and the reverse biased at applied voltage ranging from −1 V to +1 V with a scan rate of 2 mV/s. The proficient current in the PANI/TiO2 heterojunction structure was attributed to the well penetration of PANI molecules into the pores of the TiO2 nanoparticle thin film. The I–V characteristics ensured an efficient charge movement at the junction of PANI/TiO2 interface and thus, behaved as a typical ohmic system. 相似文献
994.
Shigeyuki Ishida Masamichi Nakajima Hijiri Kito Yasuhide Tomioka Toshimitsu Ito Akira Iyo Hiroshi Eisaki Shin-ichi Uchida 《Physica C: Superconductivity and its Applications》2009,469(15-20):905-907
Transport properties of BaNi2P2 single crystals prepared by high-pressure synthesis method have been investigated. The temperature dependence of the resistivity is that of a typical metal with the anisotropy ratio ρ/ρ of 6.3 and suggests that electron–phonon interaction dominates the scattering mechanism. We have also found that the Hall effect and the magnetoresistance can be explained by a two-carrier model which is consistent with a multiple-band structure with both hole and electron characters. 相似文献
995.
v 《Journal of Molecular Spectroscopy》2009,257(1):108-110
The effective correlation-free Hamiltonian and corresponding matrix elements for interacting degenerate fundamental vt(E) and combination vn(A1)+vt′(E) states in C3v molecules are derived. The Hamiltonian terms H30, H31, H32 and the recommended set of parameters following from the appropriate reduction are presented. 相似文献
996.
利用旋涂法和真空蒸镀法相结合的方法,根据能量空间传递的原理制备了PVK ∶ Ir(piq)2(acac)体系的红色有机电致发光显示器件。器件的结构为ITO/CuPc/PVK ∶ Ir(piq)2(acac)/BCP/Alq3/LiF/Al。研究了不同主客体掺杂比对器件发光性能的影响,得到了高色纯度、单色性较好的红光器件。当Ir(piq)2(acac)掺杂的质量比为1 ∶ 0.08时,器件的综合性能达到最佳,发光峰位于625 nm,CIE坐标为(x=0.66,y=0.33)。通过对各层厚度的合理选择,形成相对优化的微腔结构,充分利用其对光谱的窄化效应,使得器件的EL光谱的发射半峰全宽仅为55 nm,提高了器件的发光性能。器件光谱具有很好的单色性,色纯度达到98.2%。 相似文献
997.
998.
We aimed to examine the effects of luminance and size of stimuli upon the binocular fusion limit. A three-dimensional display
was used to present dichoptic stimuli to the left and right eye, respectively. The range of dominant wavelength was from 450
to 650 nm. We measured the binocular color fusion limits Δλ
d for each dominant wavelength λ
d quantitatively with different luminance. The results show that the binocular color fusion ceases when the color difference
introduced between the left and right eyes exceeds a certain threshold value, and the color fusion limit becomes smaller with
the increase of the luminance of stimuli. In experiment 2, we adjusted the visual size of stimuli from 2 to 10° and found
that color fusion is more difficult to achieve at 10° than at 2°. 相似文献
999.
1000.
We explore the OR gate response in a mesoscopic ring threaded by a magnetic flux . The ring is symmetrically attached to two semi-infinite one-dimensional metallic electrodes, and two gate voltages, Va and Vb, are applied in one arm of the ring; these are treated as the two inputs of the OR gate. All the calculations are based on the tight-binding model and the Green’s function method, which numerically compute the conductance–energy and current–voltage characteristics as functions of the gate voltages, ring-to-electrode coupling strengths and magnetic flux. Our theoretical study shows that, for =0/2 (0=ch/e, the elementary flux-quantum), a high output current (1) (in the logical sense) appears if one or both the inputs to the gate are high (1), while if neither input is high (1), a low output current (0) appears. It clearly demonstrates the OR gate behavior, and this aspect may be utilized in designing an electronic logic gate. 相似文献