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1.
The possibility has been shown of using IR spectroscopy in the investigation of the changes in the polysaccharide component of wood in the process of acid hydrolysis. The method of determining the relative optical density (ROD) was used for the quantitative evaluation of the changes in the functional groups of the lignocellulose.Deceased.Siberian Scientific Research Institute of Cellulose and Board, Bratsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 683–687, September–October, 1990. 相似文献
2.
N. I. Giricheva N. V. Belova G. V. Girichev S. A. Shlykov I. K. Igumenov 《Journal of Structural Chemistry》1993,33(6):831-837
Ivanovsk State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 6, pp. 76–83, November–December, 1992. 相似文献
3.
I. N. Belova N. I. Giricheva G. V. Girichev S. A. Shlykov 《Journal of Structural Chemistry》1996,37(6):889-896
The structure of the NbCl4 molecule is studied experimentally by the synchronous electron diffraction and mass spectrometry methods. The model molecular geometries of C2v, C3v, D2d, and Td symmetries are verified. The advantages of the tetrahedral model over the other models are established. The thermally averaged parameters of the effective configuration of the NbCl4 molecule are as follows: rg(Nb?Cl)=2.279(5) Å, l(Nb?Cl)=0.073(2) Å, rg(Cl?Cl)=3.692(17) Å, l(Cl?Cl)=0.275(11) Å, ∠g(Cl-Nb-Cl)=108.2(5)°, and δ(Cl?Cl)=0.030(19) Å. 相似文献
4.
The ergodic and the intermixing theorems of Yu. V. Linnik (Mat. Sb.,43, No. 2, 257–276) are generalized to arbitrary positive quadratic forms of genus of , where Ω > 1 is an odd number, of invariants [Ω,1], defined by the character for all prime numbers ρ¦Ω. One obtains estimates for the remainder term. The method of proof is simplified. 相似文献
5.
S. A. Trifonov E. A. Sosnov Yu. S. Belova A. A. Malygin N. G. Razinkova G. G. Savkin 《Russian Journal of Applied Chemistry》2007,80(8):1413-1418
The influence of a gas-phase chemical modification of low-density polyethylene with volatile halides of various elements [PCl3, TiCl4, VOCl3, BBr3, and Si(CH3)2Cl2] on the surface layer morphology and vapor permeability of polymeric formulations was examined by atomic-force microscopy, chemical analysis, and adsorption method. 相似文献
6.
S. N. Baranov R. O. Kochkanyan A. N. Zaritovskii G. I. Belova S. S. Radkova 《Chemistry of Heterocyclic Compounds》1975,11(1):73-73
A method was developed for the preparation of 4-chloro-5-formylimidazolones, Δ4-thiazolinones, and 4-chloro-5-formyluracils by reaction of 4-azolidones or barbituric acids with dimethylformamide and phosphorus oxychloride. 相似文献
7.
Ivanovo State University. Ivanovo Chemical Engineering Institute. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 4, pp. 135–138, July–August, 1994. 相似文献
8.
N. E. Britikova L. A. Belova K. A. Chkhikvadze O. Yu. Magidson 《Chemistry of Heterocyclic Compounds》1973,9(2):250-252
The 2,4,8-trioxo derivative of pyrimido[5,4-d][1,3]oxazine was synthesized, and esters and amides of 5-acetamidoorotic acid were obtained from it. The acetyl group in 5-acetamido-orotic acid esters is readily hydrolyzed in acidic media to give esters of 5-aminoorotic acid, while the acetyl group in amides of 5-acetamidoorotic acid do not undergo hydrolysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 270–272, February, 1973.Deceased. 相似文献
9.
A number of pyrimido[5,4-b]quinoline derivatives were synthesized. It is shown that in the reaction of 2,4,10-trichloropyrimido[5,4-b]quinoline (II) with strong nucleophilic reagents (OCH3 and SH) both of the halogens of the pyrimidine ring are replaced, while with amines substitution of the halogens of the pyrimidine ring proceeds successively; under more severe conditions, all three halogen atoms of II are replaced by amine residues. 相似文献
10.
E. V. Antina N. V. Belova M. B. Berezin G. V. Girichev N. I. Giricheva A. V. Zakharov A. A. Petrova S. A. Shlykov 《Journal of Structural Chemistry》2009,50(6):1035-1045
The molecular structure of zinc acetylacetonate was studied in a simultaneous electron diffraction and mass spectrometric experiment at 376(7) K and by quantum-chemical calculations. The Zn(acac)2 molecule has a structure of D 2d symmetry with the chelate rings lying in mutually perpendicular planes. The main geometrical parameters of the molecule are r h1(Zn-O) = 1.942(4) Å, r h1(C-O) = 1.279(3) Å, r h1(C-Cr) = 1.398(3) Å, r h1(C-C m ) = 1.504(5) Å, ∠(O-Zn-O) = 93.2(7)°, ∠(Zn-O-C) = 125.9(7)°, ∠(C-Cr-C) = 125.8(14)°, ∠(O-C-C m ) = 115.2(9)°. The effective rotation angle of methyl groups is close to 30°, which is indicative of the free rotation of these groups. The vibration frequencies were obtained by quantumchemical calculations, and the IR spectrum of the Zn(acac)2 molecule was interpreted. 相似文献