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141.
Yoshio Hayakawa Eiji Hayashi Haruhiko Fukaya Naohiro Terasawa Takashi Abe Kota Omori Koichi Murai 《Liquid crystals》1996,20(3):367-371
Novel liquid crystals which have the perfluoropyrrolidino group, a heterocyclic perfluoroalkyl group, and which show smectic phases have been synthesized with perfluoro-(2-pyrrolidinopropionyl fluoride) as one of the starting materials. Analogues with a polymerizable functional group also have been prepared and polymerized to give side chain liquid crystal polymers. 相似文献
142.
Koichi Ohno 《Journal of Molecular Spectroscopy》1979,77(3):329-348
Classification methods for aromatic planar vibrations are presented. These methods involve the potential energy distribution analysis and a ring motion analysis, which makes it possible to classify collective motions of CC bonds in these systems into certain typical patterns. The planar vibrations of benzene and polyacenes up to pentacene are classified in this way, and the characteristic vibrations of these molecules are so described and analyzed. Normal coordinate calculations of naphthacene and pentacene have been carried out to illustrate the classification, and results were found to be very satisfactory. 相似文献
143.
Koichi Funazo Takayuki Hirashima Minoru Tanaka Toshiyuki Shono 《Fresenius' Journal of Analytical Chemistry》1982,311(1):27-29
Summary A method is described for the determination of sulphide ion in aqueous samples by gas chromatography. Sulphide is ethylated with diethyl sulphate and the resulting diethyl sulphide is extracted with chloroform and determined with a gas chromatograph equipped with a flame ionization or a flame photometric detector. In the case of a flame photometric detector, the detection limit for sulphide ion is 0.05 g/ml. Other anions commonly found with sulphide ion do not interfere. Sulphide ion in spring waters was analysed by this new method and for comparison also by colorimetry (methylene blue). The results revealed the reliability of the new method.
Bestimmung von Sulfidspuren durch Ethylierung und Gas-Chromatographie
Zusammenfassung Sulfid wird mit Diethylsulfat ethyliert, das gebildete Diethylsulfid mit Chloroform extrahiert und gaschromatographisch mit Hilfe eines Flammenionisationsoder eines flammenphotometrischen Detektors bestimmt. Die Nachweisgrenze beträgt 0,05 g S/ml für den FPD. Anionen, die üblicherweise mit Sulfid zusammen vorkommen, stören nicht. Das Verfahren wurde, im Vergleich mit der colorimetrischen Methylenblaumethode, auf Quellwasser angewendet. Es wurde gute Übereinstimmung der Ergebnisse erzielt.相似文献
144.
The 3.51 μm HeXe laser is magnetically tuned over a wavenumber of 0.2 cm?1 and used for infrared absorption and double resonance spectroscopy. Eight rotation-vibration lines of propynal in the ν2 band are assigned by the Stark effect. Eleven microwave transitions in the v2 = 1 vibrational state are observed by the method of infrared-microwave double resonance. The rotational constants of the excited state and the band origin of the vibration ν2 are determined from the observed spectra. 相似文献
145.
146.
Yoshio Teki Takeji Takui Mitsuru Hirai Koichi Itoh Hiizu Iwamura 《Chemical physics letters》1982,89(3):263-267
Optically detected ENDOR and electron—nuclear—nuclear triple resonance of 17O were measured via phosphorescence from 3(nπ*) benzil in benzophenone-d10 crystals at high magnetic field. The n and π* spin densities on the oxygen atom are 0.201 and 0.092, respectively, the angle between the two CO bonds being 150°. 相似文献
147.
Koichi Seo 《Nuclear Physics B》1982,209(1):200-216
In the formalism presented in the previous paper, the plaquette-plaquette correlation functions in arbitrary directions are calculated for Z(2), SU(2) and SU(3) up to order g?8. Approximate restoration of rotational symmetry is observed in the continuum limit for SU(2), but much higher order corrections seem to be required in order to restore the symmetry for SU(3). The scalar glueball mass deduced from the plaquette-plaquette correlation function in the diagonal direction is 0.80 GeV, while the on-axis computation up to order g?16 predicts it to be 0.64 GeV. 相似文献
148.
Koichi Yamada 《Journal of Molecular Spectroscopy》1977,68(3):423-451
Rotational transitions of HNCO in the v4 = 1, v5 = 1, and v6 = 1 vibrational states have been measured. The assignment of the a-type qRK and qQ1 branches has been made with the help of a qualitative discussion of the vibration-rotation interactions. Effective rotational and centrifugal distortion constants have been determined precisely for each vibrational Ka-rotational state, up to Ka = 4 for the lowest excited state and Ka = 3 for the other two excited states. The Ka dependence of the effective rotational constants B and D was observed to be quite anomalous for some of the transitions because of the a-type Coriolis interactions and accidental b-type Coriolis resonances. From a discussion of the selection rules and the effect on B and D of the interactions, the first excited state of the out-of-plane vibration, ν6, has been assigned definitely to the second lowest excited vibrational state of HNCO. 相似文献
149.
P. Wallraff Koichi M.T. Yamada R. Schieder G. Winnewisser 《Journal of Molecular Spectroscopy》1985,112(1):163-172
The ν4 vibration-rotation spectrum of acetonitrile (CH3CN) has been measured using a newly constructed diode-laser spectrometer controlled digitally by a microprocessor. The spectrum was observed in the range between 890 and 960 cm?1 with Doppler-limited resolution. The P and R branches of the ν4 fundamental band have been assigned up to K = 9. A small anomaly found in the high K lines is being explained by an anharmonic resonance with the v8 = 33 state. The determined interaction constant is small, but significant. 相似文献
150.
Pi Radical cations, which are highly reactive in general, can be made persistently stable by appropriate structural modification with heteroatoms, pi-conjugated systems, and alkyl substituents. Many of these pi radical cations undergo self-association in the condensed phase. The steric control of such self-association of stabilized pi radical cations is the subject of the present article. Such an association can result in the formation of pi- and/or sigma-dimers. The pi-dimerization in particular is now considered as an important intermolecular interaction for model studies of a charge-transport phenomenon in positively doped conducting polymers. On the other hand, the intermolecular interactions can be suppressed when the pi-system is modified with sterically demanding structural units, for example, by annelation with bicycloalkene frameworks. This structural modification not only brings about unusual stabilization of the radical cations but provides valuable information on the electronic structure/properties of the positively charged pi-systems in a segregated state. 相似文献