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101.
Novel exposure system using light-emitting diodes and an optical fiber array for printing code marks
The feasibility of a novel economical and environmentally friendly exposure system using a light-emitting diode (LED) array as a light source was demonstrated. Such an exposure system is especially useful for printing two-dimensional code marks for the production management of semiconductor devices and liquid crystal display panels. The new system also uses an optical fiber matrix array connected to the LED array. The tips of the plastic optical fibers of 1mm diameter are heated and deformed into a square shape, and the square fiber ends are projected by a 1/10 reduction lens. Using LEDs with a central wavelength of 405 nm and an output power of 40mW/cm2, quasi-square code mark patterns are printed with good size repeatability in a practically feasible short time of less than 2 s. 相似文献
102.
Hiratsuka H Horiuchi H Furukawa Y Watanabe H Ishihara A Okutsu T Tobita S Yoshinaga T Shinohara A Tokitoh N Oba M Nishiyama K 《The journal of physical chemistry. A》2006,110(11):3868-3874
Photophysical and photochemical processes of 9-methyl- and 9-phenyl-9,10-dihydro-9-silaphenanthrene derivatives have been studied at room temperature and 77 K in comparison with the carbon analogue, 9,10-dihydrophenanthrene. These 9,10-dihydro-9-silaphenanthrene derivatives show smaller fluorescence quantum yield and remarkably larger Stokes shifts than those of the carbon analogue. In contrast, their phosphorescence quantum yields are two times larger than those of the carbon analogue, although the absolute value is not so large (approximately 0.1). Reaction products and intermediates produced by the 266 nm light photolysis have been studied, and it has been confirmed that 9-methyl- and 9-phenyl-9-silaphenanthrenes have been photochemically formed in methylcyclohexane at 77 K, in addition to the formation of radical cations of 9,10-dihydro-9-silaphenanthrene derivatives and the carbon-centered radical: 9-hydro-9-silaphenanthrenyl radical. 相似文献
103.
M. Tamura Y. Hiroyama A. Nishida M. Horiuchi 《Applied Physics A: Materials Science & Processing》1998,66(4):373-384
14 /cm2 dose of As ions followed by both isochronal and isothermal annealing. The elementary defects generated first during solid-phase
epitaxial recovery of implantation-induced amorphous layers at temperatures of 550 °C and/or 600 °C are {311} defects 2–3 nm
long. They are considered to be transformed into {111} and {100} defects after annealing at temperatures higher than 750 °C.
These secondary defects show the opposite annealing behavior to the dissolution and growth by the difference of their depth
positions at 800 °C. This phenomenon is explained by the diffusion of self-interstitials contained in defects. With regard
to the formation and dissolution of defects, there is no significant difference between the effects of rapid thermal annealing
(950 °C for 10 s) and furnace annealing (800 °C for 10 min).
Received: 14 November 1997/Accepted: 16 November 1997 相似文献
104.
MR103 microphones are commonly used laboratory standard microphones in Japan. When the pressure sensitivity of MR103 is calibrated by using a coupler calibration technique, higher accuracy is difficult to achieve due to deviations in the measured voltage transfer function. These deviations are peculiar to MR103, but not to B&K4160, which is also a commonly used laboratory standard microphone throughout the world. Such deviations occur even when the measurements are done consecutively under the same measurement conditions, such as polarization voltage, temperature, and static pressure.This study experimentally and theoretically considered one of the possible reasons for this deviation. The results reveal that (a) this deviation can be explained by changes in the microphone’s parameters, such as the distance between a microphone’s membrane and back-plate, and the tension of the membrane, (b) grease used to prevent leakage of gas and sound out of the coupler might be one of the reasons for this deviation, and (c) insertion of polished sapphire spacers between the microphones and the coupler might help diminish this deviation. 相似文献
105.
Structure–Property Relationship of Supramolecular Ferroelectric [H‐66dmbp][Hca] Accompanied by High Polarization,Competing Structural Phases,and Polymorphs 下载免费PDF全文
Dr. Kensuke Kobayashi Dr. Sachio Horiuchi Dr. Shoji Ishibashi Dr. Fumitaka Kagawa Prof. Youichi Murakami Prof. Reiji Kumai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17515-17522
Three polymorphic forms of 6,6′‐dimethyl‐2,2′‐bipyridinium chloranilate crystals were characterized to understand the origin of polarization properties and the thermal stability of ferroelectricity. According to the temperature‐dependent permittivity, differential scanning calorimetry, and X‐ray diffraction, structural phase transitions were found in all polymorphs. Notably, the ferroelectric α‐form crystal, which has the longest hydrogen bond (2.95 Å) among the organic acid/base‐type supramolecular ferroelectrics, transformed from a polar structure (space group, P21) into an anti‐polar structure (space group, P21/c) at 378 K. The non‐ferroelectric β‐ and γ‐form crystals also exhibited structural rearrangements around hydrogen bonds. The hydrogen‐bonded geometry and ferroelectric properties were compared with other supramolecular ferroelectrics. A positive relationship between the phase‐transition temperature (TC) and hydrogen‐bond length (<d>) was observed, and was attributed to the potential barrier height for proton off‐centering or order/disorder phenomena. The optimized spontaneous polarization (Ps) agreed well with the results of the first‐principles calculations, and could be amplified by separating the two equilibrium positions of protons with increasing <d>. These data consistently demonstrated that stretching <d> is a promising way to enhance the polarization performance and thermal stability of hydrogen‐bonded organic ferroelectrics. 相似文献
106.
Mine Shinya Lionet Zakary Shigemitsu Haruka Toyao Takashi Kim Tae-Ho Horiuchi Yu Lee Soo Wohn Matsuoka Masaya 《Research on Chemical Intermediates》2020,46(3):2003-2015
Research on Chemical Intermediates - This work spotlights the facile method to deposit cobalt oxide (CoOx) nanoparticles as a cocatalyst on Fe-MOF-bpdc to enhance its photocatalytic activity for... 相似文献
107.
Takashi Toyao Masayuki Minakata Kazushi Iyatani Afshin Ebrahimi Po-Chou Chen Chung-Bo Tsai Yu Horiuchi Masaya Matsuoka Masakazu Anpo 《Research on Chemical Intermediates》2013,39(1):415-424
A visible-light-responsive TiO2 thin film (Vis-TiO2), possessing a unique columnar structure oriented perpendicular to the substrate, has been prepared by using a radio-frequency magnetron sputtering deposition method. The unique TiO2 thin film was used as a key component of N719 dye-sensitized solar cells (DSSCs). The rough morphology caused by the columnar structure leads to enhanced photovoltaic performances of these DSSCs as a consequence of increased amounts of adsorbed dyes and facilitated diffusion of the electrolyte into Vis-TiO2 film. Additionally, photovoltaic performances of the DSSCs were found to depend strongly on the thickness of the Vis-TiO2 film, which can be readily controlled by adjusting the sputtering time conducted for deposition. Consequently, a solar-to-electric energy conversion efficiency of 2.6 % under AM 1.5 illumination was observed for an optimally performing DSSC that has a Vis-TiO2 film thickness of 6.9 μm, prepared by employing a sputtering time of 700 min. 相似文献
108.
109.
Ken‐ichi Itoh Takamitsu Utsukihara Kenji Funayama Hiroshi Sakamaki Miyuki Kanamori T. Tomoyoshi Takahashi Yoshikazu Saitoh Masatoshi Matsushita Liangyou He Chikao Hashimoto Takashi Sugiyama C. Akira Horiuchi 《应用有机金属化学》2007,21(12):1029-1032
The reaction of α,β‐unsaturated ketones with cerium (IV) sulfate tetrahydrate [Ce(SO4)2·4H2O, CS] in acetic acid gave the corresponding β‐acetoxy ketones. In the case of 2‐cyclohexen‐1‐one with CS in acetic acid, benzobicyclo[2.2.2]octen‐2‐one was obtained. The reaction mechanism also was proposed. Moreover, we report the aromatization and esterification of (R)‐(?)‐carvone by CS in acetic acid. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
110.
Toru Kanno Kiyoshi Tada Jun-ichi Horiuchi Yoshio Hamabuchi 《Reaction Kinetics and Catalysis Letters》2007,91(1):187-194
Carbonized paper sludge (C.P.S.) from an industrial waste was employed for steam reforming of methane, and Ni loaded C.P.S. pretreated at 973 K showed an initial methane conversion of over 90% at 1073 K. 相似文献