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991.
992.
We perform an extensive investigation on the α decay of heavy deformed even-even and odd-A nuclei within the multichannel cluster model. The dynamics effects of core nuclei are taken into account in dealing with the interaction matrix and the α-cluster formation. Enough decay channels are considered for convergence in solving the coupled equations. Systematic calculations have been performed for 36 even-even nuclei and 32 odd-A nuclei. The calculated results show good agreement with the available experimental data concerning total α-decay half-lives and branching ratios, including the branching ratios for high-spin states. 相似文献
993.
针对量子点场效应单光子探测器(QDFET)光吸收效率低下的问题, 提出了一种新型量子点场效应增强型单光子探测器(QDFEE-SPD). QDFEE-SPD增加了共振腔的设计, 并采用了GaAs/AlAs多层膜作为下反射镜; 对QDFEE-SPD的光吸收增强效应和光响应度进行了理论分析和模拟, 结果表明, 与没有共振腔时相比, QDFEE-SPD的吸收效率和光相应度都有了大幅度的提升, 同时为了光吸收的最优化, 吸收层厚度一般应在0.1–0.5 μm; 对QDFEE-SPD的材料样品进行了生长和测试实验, 反射谱测试和PL谱测试结果表明, QDFEE-SPD对入射光的吸收具有了明显的增强效应. 文章成果为高效率量子点场效应单光子探测技术的研究提供了新的思路.
关键词:
QDFEE-SPD
共振腔
吸收效率
光吸收增强效应 相似文献
994.
995.
996.
Jennifer E. Ni Robert D. Schmidt Chun-I Wu Timothy P. Hogan Rosa M. Trejo 《哲学杂志》2013,93(35):4412-4439
Twenty-six (Pb0.95Sn0.05Te)0.92(PbS)0.08–0.055% PbI2–SiC nanoparticle (SiCnp) composite thermoelectric specimens were either hot pressed or pulsed electric current sintered (PECS). Bloating (a thermally induced increase in porosity, P, for as-densified specimens) was observed during annealing at temperatures >603?K for hot-pressed specimens and PECS-processed specimens from wet milled powders, but in contrast seven out of seven specimens densified by PECS from dry milled powders showed no observable bloating following annealing at temperatures up to 936?K. In this study, bloating in the specimens was accessed via thermal annealing induced changes in (i) porosity measured by scanning electron microscopy on fractured specimen surfaces, (ii) specimen volume and (iii) elastic moduli. The moduli were measured by resonant ultrasound spectroscopy. SiCnp additions (1–3.5 vol.%) changed the fracture mode from intergranular to transgranular, inhibited grain growth, and limited bloating in the wet milled PECS specimens. Inhibition of bloating likely occurs due to cleaning of contamination from powder particle surfaces via PECS processing which has been reported previously in the literature. 相似文献
997.
B. Ni X. S. Chen L. J. Huang J. Y. Ding G. H. Li W. Lu 《Optical and Quantum Electronics》2013,45(7):747-753
A dual-band polarization insensitive absorber has been proposed . Unlike the previous dual band absorber composed of composite structures, only one square metal ring with a slit at the middle of each side can be used to achieve the dual-band absorption. The calculated results show two distinct absorption peaks of 0.96 at 10 GHz and 0.99 at 20 GHz. In addition, the positions of the two peaks are strongly influenced by the width of the slit (g). More importantly, the absorptions of the two peaks keep higher than 0.9 while g changing. The dual-band absorber may have many potential applications in scientific and technological areas because of its excellent absorption characteristics and concise structure. 相似文献
998.
A new electrochemical method for the sensitive detection of adenine was established on a chitosan (CTS)- and graphene (GR)-modified carbon ionic liquid electrode (CILE). CILE was prepared by mixing 1-butylpyridinium hexafluorophosphate (BPPF6) and paraffin with graphite powder. Due to the synergistic effects of GR, CILE, and the interaction of GR with IL on the electrode surface, the electrochemical performance of CTS/GR/CILE were greatly enhanced. Electrochemical behaviors of adenine on the modified electrode was investigated with a single well-defined oxidation peak appeared. The electrochemical reaction of adenine was an adsorption-controlled irreversible process, and the electrochemical parameters were further calculated. Under the optimal conditions, the oxidation peak current was proportional to adenine concentration in the range from 1.0 nmol L?1 to 70.0 μmol L?1 with a detection limit of 0.286 nmol L?1 (3σ) by differential pulse voltammetry. The established method showed the advantages such as good selectivity, stability, and repeatability. 相似文献
999.
Epitaxial Gd2O3 thin films were successfully grown on Si (001) substrates using a two-step approach by laser molecular-beam epitaxy. At the first step, a ~0.8 nm thin layer was deposited at the temperature of 200 °C as the buffer layer. Then the substrate temperature was increased to 650 °C and in situ annealing for 5 min, and a second Gd2O3 layer with a desired thickness was deposited. The whole growth process is monitored by in situ reflection high-energy electron diffraction (RHEED). In situ RHEED analysis of the growing film has revealed that the first Gd2O3 layer deposition and in situ annealing are the critical processes for the epitaxial growth of Gd2O3 film. The Gd2O3 film has a monoclinic phase characterized by X-ray diffraction. The high-resolution transmission electron microscopy image showed all the Gd2O3 layers have a little bending because of the stress. In addition, a 5–6 nm amorphous interfacial layer between the Gd2O3 film and Si substrate is due to the in situ high temperature annealing for a long time. The successful Gd2O3/Si epitaxial growth predicted a possibility to develop the new functional microelectronics devices. 相似文献
1000.
利用矢量角谱法和稳相法,研究了涡旋洛伦兹-高斯光束的远场矢量结构特征,导出了横电项(TE项)和横磁项(TM项)远场电磁场和相应能流的解析表达式。通过相应的数值计算,分析了拓扑电荷数对涡旋洛伦兹-高斯光束及其矢量结构项远场能流分布的影响。TE项由位于竖直方向的2瓣或3瓣组成,TM项可由TE项旋转90得到。涡旋洛伦兹-高斯光束在拓扑电荷数小时内部中空,外部亮环均匀分布。增大拓扑电荷数,涡旋洛伦兹-高斯光束外部亮环上的能流呈起伏分布,内部变化相对复杂。涡旋洛伦兹-高斯光束及其矢量结构项的光斑尺寸随拓扑电荷数的增大而增大,但会饱和。研究显示,涡旋洛伦兹-高斯光束在实际应用时拓扑电荷数不宜过大。 相似文献