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1.
2.
A. V. Kopylov I. V. Orekhov V. V. Petukhov A. E. Solomatin 《Physics of Atomic Nuclei》2006,69(11):1829-1832
Experiments sensitive to pp neutrinos from the Sun are very promising for precise measurement of the mixing angle ϑ
12. A νe
− scattering experiment (XMASS) and/or a charged-current experiment (indium detector) can measure the flux of electron pp neutrinos. One can find the total flux of pp neutrinos from a luminosity constraint after the contributions of 7Be and CNO neutrinos to the total luminosity of the Sun are measured. A radiochemical experiment utilizing a lithium target
has high sensitivity to the CNO neutrinos; thus, it has a good promise for precise measurement of the mixing angle and for
a test of the current theory of evolution of the stars.
The text was submitted by the authors in English. 相似文献
3.
4.
M. G. Voronkov V. I. Rakhlin S. N. Adamovich L. P. Petukhov R. G. Mirskov N. K. Yarosh A. L. Kuznetsov M. V. Sigalov 《Russian Chemical Bulletin》1986,35(4):819-821
Conclusions 1-Hydrosilatrane does not react with monosubstituted ethylenes (or acetylenes) either in the presence of platinum or rhodium complexes or upon initiation of the reactions using organic peroxides, UV irradiation, or thermal methods. By contrast, 2-methyl-6-ethyl-1,3-dioxa-6-aza-2-silacyclooctane readily takes part in hydrosilylation of the indicated unsaturated compounds when Rhacac (CO)2 is present.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khirnicheskaya, No. 4, pp. 899–901, April, 1986. 相似文献
5.
The UV spectra of Si-substituted silocyclobutanes in vacuum were studied. The bathochromic shift of the absorption band, disclosed by comparison with bands of the corresponding acyclic compounds, can be explained by the highly strained state of the four-membered ring. This same principle in disilocyclobutanes leads to the reduction of the barrier effect of the methylene group, disrupting the interaction of the silicon atoms in the unstrained molecule. 相似文献
6.
S. L. Petukhov E. V. Vladimirova B. V. Slobodin L. L. Surat 《Russian Journal of Inorganic Chemistry》2006,51(1):23-26
A tetragonal (space group I4/mmm) solid solution La2-2x
(Ca1-y
Sry)1 + 2x
Mn2O7 based on the Raddlesden-Popper phase (n = 2), which is formed by the simultaneous substitution of calcium in Ca3Mn2O7 by strontium and lanthanum, is synthesized by high-temperature annealing of La2O3, Mn2O3, CaCO3, and SrCO3 mixtures (1500°C, air). The concentration area of the solid solution in the scheme is a pentagon, whose corners correspond
to the manganites Ca3Mn2O7, Ca0.75Sr2.25Mn2O7, La0.2Sr2.8Mn2O7, La1.6Sr1.4Mn2O7, and LaCa2Mn2O7. 相似文献
7.
Conclusions It has been demonstrated that Dewar's rule is inapplicable to predictions of absorption band behavior for heteroanalogs of C6E5C6E4X. A different criterion is proposed, based on the distribution of electron density in the ground and excited states, through which correct predictions can be made.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1770–1772, August, 1987. 相似文献
8.
Grandjean D Beale AM Petukhov AV Weckhuysen BM 《Journal of the American Chemical Society》2005,127(41):14454-14465
The hydrothermal crystallization of CoAPO-5 molecular sieves has been studied using time-resolved in-situ SAXS/WAXS, UV-vis, Raman, and XAS. Data collected during heating to 180 degrees C allowed the observation of different steps occurring during the transformation of the amorphous gel into a crystalline material from a macroscopic and atomic perspective. Raman spectroscopy detected the initial formation of Al-O-P bonds, whereas SAXS showed that these gel particles had a broad size distribution ranging from ca. 7 to 20 nm before crystallization began. WAXS showed that this crystallization was sharp and occurred at around 160 degrees C. Analysis of the crystallization kinetics suggested a one-dimensional growth process. XAS showed that Co(2+) transformed via a two-stage process during heating involving (i) a gradual transformation of octahedral coordination into tetrahedral coordination before the appearance of Bragg peaks corresponding to AFI, suggesting progressive incorporation of Co(2+) into the poorly ordered Al-O-P network up to ca. 150 degrees C, and (ii) a rapid transformation of remaining octahedral Co(2+) at the onset of crystallization. Co(2+) was observed to retard crystallization of AFI but provided valuable information regarding the synthesis process by acting as an internal probe. A three-stage, one-dimensional crystallization mechanism is proposed: (i) an initial reaction between aluminum and phosphate units forming a primary amorphous phase, (ii) progressive condensation of linear Al-O-P chains forming a poorly ordered structure separated by template molecules up to ca. 155 degrees C, and (iii) rapid internal reorganization of the aluminophosphate network leading to crystallization of the AFI crystal structure. 相似文献
9.
M. A. Ryashentseva E. P. Belanova Kh. M. Minachev V. M. Polosin V. S. Bogdanov V. A. Petukhov B. I. Maksimov 《Russian Chemical Bulletin》1988,37(12):2579-2581
Conclusions The reaction of p-diethylbenzene and H2S on a chromium-containing oxide catalyst gives a thiophene analog of phenanthrene, namely, benzo[2,1-b3,4-b]dithiophene, and a thiophene analog of anthracene, namely, benzo[1,2-b4,5-b]dithiophene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2857–2859, December, 1988. 相似文献
10.
S. V. Zaitsev S. A. Petukhov S. D. Varfolomeev 《Applied biochemistry and biotechnology》1977,2(2):123-130
The kinetics of inactivation of the electron transport chain of isolated chloroplasts was investigated. Methods for the stabilization of chloroplasts were developed. The mean operating time of the system was increased by a factor of about 200. 相似文献