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101.
L. V. Zorina T. G. Prokhorova S. V. Simonov S. S. Khasanov R. P. Shibaeva A. I. Manakov V. N. Zverev L. I. Buravov É. B. Yagubskiĭ 《Journal of Experimental and Theoretical Physics》2008,106(2):347-354
The β″-(BEDT-TTF)4AI[MIII(C2O4)3] · G(AI=NH 4 + , H3O+, K+, Rb+; MIII=Fe, Cr; G = “guest” solvent molecule) family of layered molecular conductors with magnetic metal oxalate anions exhibits a pronounced dependence of the conducting properties on the type of neutral solvent molecules introduced into the complex anion layer. A new organic dichlorobenzene (C6H4Cl2)-containing conductor of this family, namely, β″-(BEDT-TTF)4H3O[Fe(C2O4)3] · C6H4Cl2, is synthesized. The structure of the synthesized single crystals studied by X-ray diffraction is characterized by the following parameters: a = 10.421(1) Å, b= 19.991(2) Å, c= 35.441(3) Å, β = 92.87(1)°, V= 7374(1) Å3, space groupC2/c, and Z = 4. In the temperature range 0.5&;2-300 K, the conductivity of the crystals is metallic without changing into a superconducting state. The magnetotransport properties of the crystals are examined in magnetic fields up to 17 T at T = 0.5 K. In fields higher than 10 T, Shubnikov-de Haas oscillations are detected, and the Fourier spectrum of these oscillations contains two frequencies with maximum amplitudes of about 80 and 375 T. The experimental results are compared with the related data obtained for other phases of this family. The possible structural mechanisms of the effect of a guest solvent molecule on the transport properties of the β″-(BEDT-TTF)4AI[MIII(C2O4)3] · G crystals are analyzed. 相似文献
102.
Tomsk Medical Institute. Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 136–137, January–February, 1988. 相似文献
103.
104.
L. N. Zorina O. G. Safiev D. L. Rakhmankulov 《Chemistry of Heterocyclic Compounds》1988,24(6):646-647
The homolytic alkylation of benzimidazoles by 1,4-dioxane has been studied. Introduction of an ethyl group at position 1 and a sulfonic group at position 2 of the heterocycle lowers the yield of products of substitution of hydrogen or the sulfonic group at position 2 by a dioxanyl radical.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 791–792, June, 1988. 相似文献
105.
I. K. Petrushenko V. I. Smirnov K. B. Petrushenko E. Yu. Shmidt N. V. Zorina Yu. Yu. Rusakov A. M. Vasil’tsov A. I. Mikhaleva B. A. Trofimov 《Russian Journal of General Chemistry》2007,77(8):1386-1394
Fluorescence quenching of 1,4-bis(1H-pyrrol-1-yl)benzene, 1-(1H-pyrrol-2-yl)-1-(1-vinyl-1H-pyrrol-1-yl)benzene, and 1,4-bis(1-vinyl-1H-pyrrol-2-yl)benzene with chloromethanes (methylene chloride, chloroform, and carbon tetrachloride) in solvents with different polarities follows electron-transfer mechanism. The occurrence of an electron-transfer step is confirmed by formation of short-lived pyrrolylbenzene radical cations. An exception is quenching of fluorescence of 1,4-bis(1-vinyl-1H-pyrrol-2-yl)benzene in n-hexane in the presence of CCl4 and CHCl3 and in pure CCl4. In this case, neutral 1,4-bis(1-vinyl-1H-pyrrol-2-yl)benzene·-Cl radical is formed via recombination of 1,4-bis(1-vinyl-1H-pyrrol-2-yl)benzene radical cation and chloride anion. A relation was found between the nature of the short-lived species detected by laser photolysis and stable product obtained by stationary photolysis. 相似文献
106.
A. V. Afonin I. A. Ushakov D. E. Simonenko E. Yu. Shmidt N. V. Zorina A. I. Mikhaleva B. A. Trofimov 《Russian Journal of Organic Chemistry》2005,41(10):1516-1521
According to the 1H and 13C NMR data, bifurcated intramolecular hydrogen bond NH?N?HN in 2,6-bis(2-pyrrolyl)pyridine fixes its molecule in a conformation with syn orientation of the pyrrole rings. An analogous bifurcated hydrogen bond CH?N?HC is formed in 2,6-bis(1-vinyl-2-pyrrolyl)pyridine. 2-(1-Vinyl-2-pyrrolyl)-6-(2-pyrrolyl)pyridine is characterized by unsymmetrical bifurcated hydrogen bond NH? N?HC. 相似文献
107.
L. N. Zorina O. G. Safiev D. L. Rakhmankulov 《Chemistry of Heterocyclic Compounds》1989,25(3):261-263
When 5,6-benzo-1,4-dioxane was reacted with N,N-dialkylchloramines in the presence of FeSO4 at 10–20C in a solution of acetic and sulfuric acids, 6-(N,N-dialkylamino)benzo-1,4-dioxanes and 6-chloro- and 6,7-dichloro-benzo-1,4-dioxanes were obtained. Under the conditions used in the study mainly chlorination products were synthesized. Reaction of 5,6-benzo-1,4-dipxane with the system (NH3OH)2SO4-TiCl3 resulted in the formation of 6-aminobenzo-1,4-dioxane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 316–318, March, 1989. 相似文献
108.
109.
We extended prior studies on the influence of impeller type on fermentation performance to include a novel low-power-number,
high-efficiency radial flow impeller, the CD-6, possessing six curved blades on a disk turbine. Dual impeller combinations
of CD-6/CD-6, CD-6/Maxflo T, and CD-6/HE-3 were compared with Rushton/Rushton and Maxflo T/Maxflo T base cases. Qualitative
comparisons of unaerated and aerated power draw in both water and glycerol were conducted. These suggested minimal power drops
with aeration for dual CD-6 impellers and hybrids containing the CD-6 impeller design. We also examined fermentation performance
for Streptomyces and Glarea secondary metabolite fermentations. A qualitative comparison of the data suggested that dual CD-6 impellers and hybrids containing
the CD-6 impeller design resulted in reasonable power draws, improved mass transfer rates with airflow increases, and acceptable
peak titers. These arrangements may warrant further study under a wider range of production conditions. 相似文献
110.
Junker BH Mann Z Seeley A Zhang J Greasham R 《Applied biochemistry and biotechnology》2002,97(2):63-78
A defined medium and fed-batch feeding process for the production of a yeast biocatalyst, developed at the 23-L scale, was scaled up to the 600-L pilot scale. Presterilized 100-L-vol plastic bags were implemented for the pilot-scale nutrient feeding. Medium of increased concentration Oqs implemented at the pilot scale, and equivalent dry cell weights were reached with a medium 80% more concentrated than that used at the laboratory scale. The higher medium concentration was believed to be necessary at the pilot scale owing to the additional heat stresses on key components (e.g., complexing of magnesium sulfate with phosphate), increased dilution during sterilization, lower evaporation rate owing to the lower vessel volume per minute air flow rate, and increased dilution owing to nutrient feeding or shot additions. Peak cell density was found to be somewhat insensitive to variations in residual glucose levels. These results suggest that defined medium developed at the laboratory scale may need to be further optimized at the pilot scale for equivalent performance. 相似文献