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631.
The axial position of a laser-trapped particle has been controlled by modification of the wave front by means of a membrane deformable mirror. The mirror gives wave-front modulation in terms of Zernike polynomials. By modulation of the Zernike defocus term we can modulate the particle position under conditions of laser trapping. A polystyrene particle of 1-microm diameter was moved along the optical axis direction for a distance of 2370 nm in minimum steps of 55.4 nm. We also demonstrated particle oscillation along the optical axis by changing the focal position in a sinusoidal manner. From the frequency dependency of the amplitude of particle oscillation we determined the spring constant as 91.7 nN/m. 相似文献
632.
Yoshisuke Futami Satoshi Kudoh Fumiyuki Ito Taisuke Nakanaga Munetaka Nakata 《Journal of Molecular Structure》2004,690(1-3):9-16
The CH3Cl and CH3Br dimers produced by supersonic-jet expansion were directly deposited on a cold plate using a standard matrix-isolation technique. Dependence of the relative intensities of the observed infrared bands on the stagnation pressure was used to assign the dimer bands appearing near the monomer bands. By a comparison of the wavenumber shifts from the monomer bands with the corresponding values obtained by quantum chemical calculations, DFT/B3LYP/6-311++G(3pd,3df) and MP2/LanL2DZ+fdp, the structures of CH3Cl and CH3Br dimers were determined to be a head-to-tail isomer, which is common to the CH3F and CH3I dimers determined previously by the same method. The remaining dimer bands, which could not be assigned to the head-to-tail isomer, were tentatively assigned to a head-to-head isomer in analogy with CH3I dimer. 相似文献
633.
T. Ozaki 《Annals of the Institute of Statistical Mathematics》1979,31(1):145-155
Summary A maximum likelihood estimation procedure of Hawkes' self-exciting point process model is proposed with explicit presentations
of the log-likelihood of the model and its gradient and Hessian. A simulation method of the process is also presented. Some
numerical results are given.
The Institute of Statistical Mathematics 相似文献
634.
K. Fujii H. Hayashii S. Iwata R. Kajikawa A. Miyamoto T. Nakanishi Y. Ohashi S. Okumi H. Ozaki T. Tauchi T. Yamaki K. Mori Y. Takeuchi 《Nuclear Physics B》1981,187(1):53-70
The polarized target asymmetry for γn→π?p was measured over the second resonance region from 0.55 to 0.9 GeV at pion c.m. angles between 60° and 120°. A double-arm spectrometer was used with a deuterated butanol target to detect both the pion and the proton, thus considerably improving the data quality. Including the new data in the amplitude analysis, the radiative decay widths of three resonances were determined more accurately than before. The results are compared with various quark models. 相似文献
635.
636.
Ion heating and high-energy-particle production by ion-cyclotron heating in the large helical device
Mutoh T Kumazawa R Seki T Watari T Saito K Torii Y Hartmann DA Zhao Y Sasao M Isobe M Osakabe M Krasilnikov AV Ozaki T Narihara K Nagayama Y Inagaki S Shimpo F Nomura G Yokota M Akaishi K Ashikawa N de Vries P Emoto M Funaba H Fukuyama A Goto M 《Physical review letters》2000,85(21):4530-4533
Ion-cyclotron heating was applied to the Large Helical Device. When the proton-cyclotron resonance was near the saddle point of the magnetic field-strength plane, strong ion-cyclotron damping occurred. Under these conditions efficient plasma heating was achieved for more than one minute. A high-energy ion tail was observed, and the effective tail temperature was determined by a balance between the wave acceleration and the electron-drag relaxation. There was no apparent sign of particle orbit loss effect in the investigated density range of 0.8-1.3x10(19) m(-3). 相似文献
637.
Taisuke Matsuno Maki Someya Sota Sato Satoshi Maeda Hiroyuki Isobe 《Angewandte Chemie (International ed. in English)》2020,59(34):14570-14576
A supramolecular/synthetic method has been devised to affix a sterically hindered substituent onto a fullerene guest encapsulated in a tubular host. A two‐wheeled complex of (C59N)‐(C59N) with a tubular host was oxidatively bisected to afford a C59N+ cation captured in the tube. The C59N+ cation in the tube was then trapped by ethanol or water, which led to an oxy substituent pinned on the guest. The guest motions within the tube were modulated by the pinned substituent, and up‐and‐down flipping motions were halted by an ethoxy substituent. A hydroxy substituent, however, was ineffective in halting the flipping motions, despite the tight‐fitting relationship between the tubular host and the spherical guest. Theoretical calculations of the dynamics revealed that the flipping motions were assisted by OH‐π hydrogen bonds between the guest and the carbon‐rich wall and that sliding motions of the OH group were also facilitated by deformations of the tube. 相似文献
638.
Thanyada Sukmanee Dr. Kanet Wongravee Dr. Yasutaka Kitahama Prof. Dr. Sanong Ekgasit Dr. Tamitake Itoh Dr. Prompong Pienpinijtham Prof. Dr. Yukihiro Ozaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14672-14677
Discrimination between enantiomers is achieved by tip-enhanced Raman scattering (TERS) using a silver tip that is chemically modified by an achiral para-mercaptopyridine (pMPY) probe molecule. Differences in the relative intensities of the pMPY spectra were monitored for three pairs of enantiomers containing hydroxy (−OH) and/or amino (−NH2) groups. The N: or N+−H functionality of the pMPY-modified tip participates in hydrogen-bond interactions with a particular molecular orientation of each chiral isomer. The asymmetric arrangement of silver atoms at the apex of the tip induces an asymmetric electric field, which causes the tip to become a chiral center. Differences in the charge-transfer (CT) states of the metal-achiral probe system in conjunction with the asymmetric electric field produce different enhancements in the Raman signals of the two enantiomers. The near-field effect of the asymmetric electric field, which depends on the number of analyte functional groups capable of hydrogen-bond formation, improves the degree of discrimination. 相似文献
639.
Mondo Izawa Taisuke Suito Shin‐ichiro Ishida Daiki Shimizu Takayuki Tanaka Tadashi Mori Atsuhiro Osuka 《化学:亚洲杂志》2020,15(9):1440-1448
Highly twisted structures of expanded porphyrin provide a prominent basis to unravel the relationship between aromaticity and chirality. Here we report the synthesis of bis‐Ge(IV) complexes of [38]octaphyrin that display rigid figure‐eight structures. Two bis‐Ge(IV) [38]octaphyrin isomers with respect to the stereochemistry of the axial hydroxy groups on the germanium ions were obtained and found to be aromatic. Upon oxidation with MnO2, these [38]octaphyrin complexes were converted to a single syn‐type isomer of [36]octaphyrin with retained figure‐eight conformation. The enantiomers have been successfully separated by HPLC equipped with a chiral stationary phase. While aromatic [38]octaphyrin Ge(IV) complexes showed quite large molar circular dichroism of up to Δ?=1500 M?1cm?1 with a dissymmetry factor gabs of 0.035, weakly antiaromatic [36]octaphyrin Ge(IV) complexes underscored moderate values; Δ?=540 M?1cm?1 with gabs of 0.023. Thus, the figure‐eight octaphyrin scaffold has been proved to be an attractive platform for novel chiroptical materials with tunable aromaticity. 相似文献
640.