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采用时域有限差分(FDTD)法研究Au纳米颗粒@碳球(AuNPs@CS)复合结构的光吸收控制。发现Au纳米颗粒@碳球复合结构中Au颗粒的位置可以控制复合结构光吸收。模型计算中选取两粒Au纳米颗粒以最佳深度(0 nm)嵌入碳球表面。当两粒Au颗粒球心与碳球球心夹角为22.5°和45°时,复合结构光吸收较单一碳球光吸收明显增强;当夹角为315°、270°、180°、90°时,光吸收增量逐渐减小;当夹角为337.5°时,光吸收量低于单一碳球。这一结果主要归因于Au纳米颗粒位置变化可引起表面等离子体光强度和光散射方向的变化。改变碳球表面Au纳米颗粒的数量和位置,可以进一步调节AuNPs@CS复合结构的光吸收。 相似文献
54.
金属Zn液态结构变化的研究 总被引:2,自引:0,他引:2
利用TB模型给出的原子间相互作用势详细计算了不同温度下Zn的双体分布函数g(r),结果发现随着温度的不断降低,液态金属Zn的g(r)第一峰变得高而尖,第二峰由弱变强,说明了液态金属Zn的有序度随温度降低而不断增强;利用键对分析技术统计了液态金属Zn在不同温度下的键取向序参数、键对数。键取向序参数及键对数随温度的变化,进一步证明了低温液态的有序度高于高温液态,从而充分说明液态金属在不同温度下有不同的结构形式,而不像人们想象得那样杂乱无章。 相似文献
55.
Xiangli Qian Huiying Sun Tianlu Chen Danzengluobu Youliang Feng Qi Gao Quanbu Gou Yiqing Guo Hongbo Hu Mingming Kang Haijin Li Cheng Liu Maoyuan Liu Wei Liu Bingqiang Qiao Xu Wang Zhen Wang Guangguang Xin Yuhua Yao Qiang Yuan Yi Zhang 《Frontiers of Physics》2022,17(6):64602
The High Altitude Detection of Astronomical Radiation (HADAR) experiment is a refracting terrestrial telescope array based on the atmospheric Cherenkov imaging technique. It focuses the Cherenkov light emitted by extensive air showers through a large aperture water-lens system for observing very-high-energy γ-rays and cosmic rays. With the advantages of a large field-of-view (FOV) and low energy threshold, the HADAR experiment operates in a large-scale sky scanning mode to observe galactic sources. This study presents the prospects of using the HADAR experiment for the sky survey of TeV γ-ray sources from TeVCat and provids a one-year survey of statistical significance. Results from the simulation show that a total of 23 galactic point sources, including five supernova remnant sources and superbubbles, four pulsar wind nebula sources, and 14 unidentified sources, were detected in the HADAR FOV with a significance greater than 5 standard deviations (σ). The statistical significance for the Crab Nebula during one year of operation reached 346.0 σ and the one-year integral sensitivity of HADAR above 1 TeV was ~1.3%–2.4% of the flux from the Crab Nebula. 相似文献
56.
<正>The optical performance of thin film polarizers is highly sensitive to the layer thicknesses of thin film.The thicknesses of the sensitive layers are optimized in order to gain broader polarizing zone in such case when the total layer thickness does not increase.An automatic layer thickness control system is established,and errors caused by different monitoring methods are analyzed.With this thickness control system,thin-film polarizers with T_p higher than 98%and T_p/T_s higher than 200:1(T_p and T_s are transmissions for p- and s-polarizations,respectively) with the bandwidth of 11 nm are prepared.Using the system allows for optimum repeatability of three successive runs. 相似文献
57.
The synthesis and characterization of Zr‐POSS and Hf‐POSS coordination polymers were reported. The IR data and the solid‐state 29Si MAS NMR indicated the existence of Si? O? M linkage. The polarized optical microscopy images and the XRD data suggested their crystalline nature. 相似文献
58.
Fen Yu Dr. Xuan Fang Huimin Jia Miaoxing Liu Xiaotong Shi Chaowen Xue Dr. Tingtao Chen Prof. Zhipeng Wei Prof. Fang Fang Prof. Hui Zhu Prof. Hongbo Xin Prof. Jing Feng Prof. Xiaolei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8053-8058
For the first time, the influence of different types of atoms (Zn and O) on the antibacterial activities of nanosized ZnO was quantitatively evaluated with the aid of a 3D‐printing‐manufactured evaluation system. Two different outermost atomic layers were manufactured separately by using an ALD (atomic layer deposition) method. Interestingly, we found that each outermost atomic layer exhibited certain differences against gram‐positive or gram‐negative bacterial species. Zinc atoms as outermost layer (ZnO?Zn) showed a more pronounced antibacterial effect towards gram‐negative E. coli (Escherichia coli), whereas oxygen atoms (ZnO?O) showed a stronger antibacterial activity against gram‐positive S. aureus (Staphylococcus aureus). A possible antibacterial mechanism has been comprehensively discussed from different perspectives, including Zn2+ concentrations, oxygen vacancies, photocatalytic activities and the DNA structural characteristics of different bacterial species. 相似文献
59.
Hongbo Li C. H. M. van der Werf A. Borreman J. K. Rath Ruud E. I. Schropp 《固体物理学:研究快报》2008,2(4):157-159
In this letter we report the result of an a‐Si:H/nc‐Si:H tandem thin film silicon solar mini‐module fabricated on plastic foil containing intrinsic silicon layers made by hot‐wire CVD (efficiency 7.4%, monolithically series‐connected, aperture area 25 cm2). We used the Helianthos cell transfer process. The cells were first deposited on a temporary aluminum foil carrier, which allows the use of the optimal processing temperatures, and then transferred to a plastic foil. This letter reports the characteristics of the flexible solar cells obtained in this manner, and compares the results with those obtained on reference glass substrates. The research focus for implementation of the hot‐wire CVD technique for the roll‐to‐roll process is also discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
60.
The effects of repeating thickness periods on stress are studied in ZrO2/SiO2 multilayers deposited by electron-beam evaporation on BK7 glass and fused-silica substrates. The results show that the residual stress is compressive and decreases with an increase of the periods of repeating thickness in the ZrO2/SiO2 multilayers. At the same time, the residual stress in multilayers deposited on BK7 glass is less than that of samples deposited on fused silica. The variation of the microstructure examined by x-ray diffraction shows that microscopic deformation does not correspond to macroscopic stress, which may be due to variation of the interface stress. 相似文献