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141.
利用多靶磁控溅射技术制备了Au/SiO2纳米颗粒分散氧化物多层复合薄膜.研究了在保持Au单层颗粒膜沉积时间一定时薄膜厚度一定、变化SiO2的沉积时间及SiO2的沉积时间一定而改变薄膜厚度时,多层薄膜在薄膜厚度方向的微观结构对吸收光谱的影响.研究结果表明:具有纳米层状结构的Au/SiO2多层薄膜在560 nm波长附近有明显的表面等离子共振吸收峰,吸收峰的强度随Au颗粒的浓度增加而增强,在Au颗粒浓度相同的情况下,复合薄膜
关键词:
2纳米复合薄膜')" href="#">Au/SiO2纳米复合薄膜
多靶磁控溅射
吸收光谱
有效介质理论 相似文献
142.
苝二酸酐与嘧啶衍生物的氢键组装 总被引:1,自引:0,他引:1
用半经验AM1方法对苝二酸酐与嘧啶衍生物的1:1及1:2氢键复合物进行理论研究,表明随着氢键数目增多,弱相互作用能变大,主体上的供电基和客体上的吸电基有利于氢键相互作用,氢键导致电子从主体流向客体.用INDO/SCI方法计算配合物的电子光谱,表明其长波吸收峰与主体相比发生兰移,各配合物的长波吸收峰位置相差不大,与实验一致.讨论吸收峰兰移的原因并对电子跃迁进行理论指认,同时得到了配合物的双质子转移势能曲线,给出了相对于N-H键的过渡态和活化能. 相似文献
143.
E. Nir Ch. Plützer K. Kleinermanns M. de Vries 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(3):317-329
The vibronic spectra of laser desorbed and jet cooled guanine (G) adenine (A), and cytosine (C) consist of bands from four,
two and two major tautomers respectively, as revealed by UV-UV and IR-UV double resonance spectroscopy. The vibronic spectrum
of adenine around 277 nm consists of weak nπ* and strong ππ* transitions, based on IR-UV and deuteration experiments. Precise ionization potentials of G and A were determined with 2-color,
2-photon ionization. We also measured vibronic and IR spectra of several base pairs. GC exhibits a HNH ... OH/NH ... N/C=O ... HNH bonding similar to the Watson-Crick GC base pair but with C as enol tautomer. One GG isomer exhibits non-symmetric hydrogen
bonding with HNH ... N/NH ... N/C=O ... HNH interactions. A second observed GG isomer has a symmetrical hydrogen bond arrangement with C=O ... NH/NH ... O=C bonding. Two CC isomers were observed with symmetrical C=O ... NH/NH ... O=C bonding and nonsymmetrical C=O ... HNH/NH ... N interaction, respectively. Guanosine (Gs), 2-DeoxyGs und 3-DeoxyGs each exhibit only one isomer in the investigated wavelength
range around 290 nm with a strong intramolecular sugar(5-OH) ... enolguanine(3-N) hydrogen bond.
Received 16 June 2002 / Received in final form 15 July 2002 Published online 13 September 2002 相似文献
144.
针对高功率二极管重复率抽运的V型非稳腔Yb3+∶YAG激光头,提出了利用金刚石窗口冷却和直接水冷相结合的复合冷却设计.在YAG片的抽运面进行直接水冷,同时在激光提取面利用金刚石窗口冷却介质.金刚石优异的导热性能不仅能够有效地冷却激光介质,还能消除横向的温度梯度,解决了高功率激光器冷却和高功率抽运的矛盾.模拟结果表明对掺杂10 at %厚度为1.6 mm的Yb3+∶YAG片在抽运功率密度为20 kW/cm2,重复频率为10 Hz的条件下,要将最高温度控制在可接受的范围内(比如320 K),周围冷却水的对流换热系数约为4000 W/m2K. 相似文献
145.
146.
147.
148.
This article presents the comparison of approximate and exact small-signal theories for analyzing the influence of the higher-order dispersion terms on dispersive optical communication systems operating near zero dispersion wavelength for linear single-mode fiber. For the approximate theory, the generalized conversion matrix has been reported and gives the transfer function of intensity and phase from the fiber input to fiber output for a laser source including the influence of any higher-order dispersion term. In addition, expressions for the small-signal frequency response and the relative intensity noise (RIN) response of an ultrafast laser diode including noises are derived. However, it is observed that the approximation assumed for the second-order dispersion term for the approximate analysis is not valid. From the approximate theory, the exact generalized conversion matrix and exact expressions for small-signal frequency response and relative intensity noise (RIN) are obtained. We show that for the exact theory, the second-order dispersion term has no effect on intensity and frequency response even at large modulating frequencies and large propagation distances contrary to the approximate theory as reported by other authors. But we show that third-order dispersion term certainly has some minute impact on the frequency and RIN response for long distance links at high modulating frequencies. 相似文献
149.
A vacuum-deposited aluminium layer (20 nm) is sandwiched between two layers of laminated oriented polypropylene (OPP) film whose thickness varies from 20 to 40 μm. Selected areas of this sealed system were transparentised by the redistribution of the aluminium layer without breaking the seal or causing damage to the OPP film using a 75 W Q-switched Nd:YAG laser. The resultant transparentised films contain aluminium particles, distorted polymer areas and intact areas of the vacuum-coated aluminium layer. This paper investigates the effect of microscopic features upon the overall transmissivity of the laser-treated films and hence the quality of the transparentisation process. 相似文献
150.
Nobuaki Kanamaru 《Journal of luminescence》2002,96(1):5-35
Time-resolved fluorescence spectra of a title molecule (with benzene and aliphatic amine parts) in various media, after excitation by several lasers were observed to complement the previous work by conventional spectroscopy [N. Kanamaru, J. Tanaka, J. Phys. Chem. 95 (1991) 6441]. Though complex with many new features, the results were roughly consistent with the previous ones. The significant conclusions are as follows: (1) The emission to be ascribed to the amine (N) part, with more than one component (of nN and aN types) is observed not only for the acetonitrile solution (as previously reported) but also for all the other media. (2) Contrary to the case of a nonpolar hexane solution, both of N fluorescences in the other media reveal unusually long-lived decay components. This can be interpreted by assuming the so-called charge-transfer-to-solvent (CTTS) state that is nonfluorescent and lies just below the fluorescent state. (3) This observation in the protic media can also be taken as another evidence of the peculiar hydrogen bonding between this amine and the protic solvent molecules [N. Kanamaru, J. Tanaka, J. Phys. Chem. 95 (1991) 6441]. (4) Thus, the unexpectedly large quantum yields of N fluorescences in the polar media are now interpreted as arising due to the slow S1N→(CTTS)→S0 internal conversions. 相似文献