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461.
Eiichi Yagi 《Hyperfine Interactions》1994,84(1):43-45
The behaviour of hydrogen in metals has been investigated by a channelling method utilizing a nuclear reaction1H(11B, ). The results are briefly summarized. 相似文献
462.
L X-ray spectra of iodine and antimony compounds were measured using a doublecrystal spectrometer, L4 X-rays emitted from the valence 5p electrons were found to be sensitive to the chemical environment. The L4/L3, L1/L1 and L2,15/L1 intensity ratios were remarkably changed in various compounds of these elements. L4 energies of iodine compounds were shifted with the increase of the formal oxidation number. 相似文献
463.
464.
Yoshito Takeuchi Kazuyuki Suzuki Takashi Yagi Yusuke Yoshida Yoshitake Suzuki 《应用有机金属化学》2005,19(1):104-107
A novel phenyl–bromine ligand exchange reaction by BBr3 on germanium was investigated that proceeds without breaking Ge CH2Ar bond. Typically, the reaction between (PhCH2)3PhGe and BBr3 resulted exclusively in the formation of (PhCH2)3GeBr. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
465.
In order to lower the redox potentials of Os(III/II) complexes, the mixed ligand complexes of Os(II) were synthesized. The redox potentials of Os(III/II) complexes could be lowered by the use of 4,4'-dimethyl-2,2'-bipyridine (dmbpy), imidazole (Him) or its derivatives, and chloride ion as ligands, e.g., values of the redox (formal) potentials of 628 mV vs. Ag/AgCl for [Os(bpy)3]3+/2+ (bpy: 2,2'-bipyridine) and -6 mV for [OsCl(Him)(dmbpy)2]2+/+ were given in deaerated 0.1 mol dm-3 phosphate buffer (pH 7.0). The evaluation of Os(II) complexes as electron transfer mediators accessible for amperometric glucose sensors was examined according to the determination of the redox potentials of Os(III/II) complexes and the second-order rate constants for electron transfer between glucose oxidase (GOx) in reduced form and the Os(III) complex. Although the Os(II) complexes with lower redox potentials tended to decrease the second-order rate constants ks, the ks values for the majority of Os(II) complexes synthesized in this study were greater than that for ferrocenecarboxylic acid. Acceleration of the electron-transfer reaction is attributable to the hydrogen bonding and/or the electrostatic interaction between the Os(II) complexes and GOx. It may be consequently concluded that the mixed ligand complexes of Os(II) with bpy (dmbpy), Him (its derivatives), and Cl- can act as more efficient electron transfer mediators for the fabrication of amperometric glucose sensors. 相似文献
466.
T. Matsumura A. Kazama T. Yagi 《Applied Physics A: Materials Science & Processing》2005,81(7):1393-1398
A mechanism of debris accumulation around the hole created on a silicon substrate with a femtosecond laser is experimentally studied. The hole created by the laser pulses has an edge consisting of pillared structures. However, no solid or liquid materials with similar dimensions as the pillared structures were ejected from the hole as the laser machining was performed in vacuum or in the presence of various gases. When the target was placed in a gas under 100 Torr, a thick layer of cotton-like material formed around the hole. Laser irradiation of a vertically placed target resulted in re-solidified material that formed after dripping from the hole edge, showing that substrate was partially melted. The surface morphology features suggest that the debris was formed as a result of aggregation of small particles such as atoms or atomic clusters on the substrate surface instead of large-scale droplets or fragments, which are commonly observed with nanosecond lasers. PACS 78.67.Bf; 81.15.Fg; 81.16.Mk; 81.20.Wk; 81.65.Cf 相似文献
467.
468.
In the present paper, we investigate the fundamental trade-off of identification, secret-key, storage, and privacy-leakage rates in biometric identification systems for remote or hidden Gaussian sources. We use a technique of converting the system to one where the data flow is in one-way direction to derive the capacity region of these rates. Also, we provide numerical calculations of three different examples for the system. The numerical results imply that it seems hard to achieve both high secret-key and small privacy-leakage rates simultaneously. 相似文献
469.
Masahito Tanaka Kazutoshi Yagi‐Watanabe Fusae Kaneko Kazumichi Nakagawa 《Journal of synchrotron radiation》2009,16(4):455-462
Natural circular dichroism (CD) spectra in the extreme ultraviolet (EUV) region down to a wavelength of 80 nm have been observed for the first time, using an alanine thin film deposited on sodium salicylate coated glass as a sample. Calibrated EUV‐CD spectra of l ‐alanine exhibited a large negative peak at around 120 nm and a positive CD signal below 90 nm, which were roughly predicted by theoretical calculations. A CD measurement system with an Onuki‐type polarizing undulator was used to obtain the EUV‐CD spectra. This CD system, the development of which took five years, can be used to observe even weak natural CD spectra. The polarization characteristics of this system were also evaluated in order to calibrate the recorded CD spectra. 相似文献
470.
Colloidal magnetite particles coated with chondroitin sulfate (abbreviated as Fe/CS) were prepared under conditions of varying
Fe(II) fractions at a fixed Fe concentration and a given concentration of CS. The average size of the magnetite core region
was estimated as 7 nm from transmittance electron microscopy measurements, while the size of the Fe/CS particles ranged 155–175 nm,
as estimated using Rayleigh scattering measurements by reference to a control size derived from the dynamic light scattering.
The reaction of various Fe/CS with NO−
2 in aqueous solutions was determined by fluorometry using 2,3-diaminonaphthalene as a probe and by gas chromatography–mass
spectrometry. The concentrations of NO−
2 in the reaction mixtures decreased in the presence of Fe/CS to a greater extent under Ar compared with aerobic conditions.
The reactivity of Fe/CS toward NO−
2 under aerobic conditions increased with decreasing the size of Fe/CS particles or with increasing content of Fe(III) in the
Fe/CS solutions, but was independent of the Fe(II) fraction in the preparation process. While CS molecules had no influence
on the NO−
2 decomposition, those coated with the magnetite core may prevent the diffusion of NO−
2 to be adsorbed on the core surfaces. NO−
2 was concluded to undergo redox reactions with Fe(II) and Fe(III) located on the core surface of magnetite crystalline structures
of Fe/CS.
Received: 12 April 2000/Accepted: 9 August 2000 相似文献