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71.
L. V. Gorshkova V. P. Zvolinskii N. S. Prostakov A. V. Varlamov M. Torres V. F. Zakharov 《Chemistry of Heterocyclic Compounds》1980,16(12):1245-1248
The diene condensation of 1,3-diphenyl-2-azaanthracene with maleic anhydride proceeds under more severe conditions than the analogous condensation with anthracene. On the basis of an analysis of the PMR data for the adduct obtained it was assumed that isomers of ,-[9,10-dihydro-2-aza-1,3-diphenylanthrylene(9,10)]succinic anhydride with respect to the position of the anhydride bridge relative to the pyridine ring are formed in this condensation. 9,10-Dihydro-2-aza-1,3-diphenyl-9, 10-(1-cyanoethylene)anthracene was obtained in the condensation of the same azaanthracene with acrylonitrile. ,-[5H-8-Aza-7-phenylbenzo[a]fluoranthrylene (5,12b) ]succinic anhydride is formed as a result of the similar condensation of 8-aza-7-phenylbenzo[a]fluoranthene with maleic anhydride, while isomeric (with respect to the position of the nitrile group in the ethylene bridge) 5H-8-aza-7-phenyl-5,12b-(cyanoethylene)benzo[a]fluoranthenes were isolated in its condensation with the acrylonitrile. Data from the PMR and IR spectra were used to prove the structures of the adducts of the diene synthesis obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1645–1647, December, 1980. 相似文献
72.
Yu.A. Ustynyuk P.I. Zakharov A.A. Azizov V.K. Potapov I.M. Pribytkova 《Journal of organometallic chemistry》1975,88(1):37-64
Dissociative ionisation of organometallic cyclopentadiene derivatives containing one, two or three M(CH3)3 groups (M Si, Ge, Sn) has been studied.Among the monometallated compounds, C5H5Si(CH3)2Cl, C5H5Si(CH3)2OCH3 and (C5H5)4Sb have also been investigated. To verify fragmentation patterns, the spectra of deuterated compounds such as C5D5Si(CH3)3, C5D5Sn(CH3)3, C5D4Si2(CH3)6 and C5D3Si3)9 have been measured. Dissociative ionisation of h1-cyclopentadienyl derivatives has been shown to differ essentially from that of h5-compounds. 相似文献
73.
L. V. Pankratov V. I. Nevodchikov L. N. Zakharov G. K. Fukin S. Ya. Khorshev M. N. Bochkarev Yu. T. Struchkov 《Russian Chemical Bulletin》1994,43(2):295-298
Dehydrogenation of pentafluorophenylgermane in the presence of catalytic amounts of a Wilkinson complex, certain RhI
ortho-benzosemiquinolate complexes, or (Ph3P)4Pt leads to tetrahydrodigermane, C6F5H2GeGeH2C6F5. X-ray analysis has confirmed thetrans-arrangement of the C6F5-cycles at the Ge atoms. The Ge-Ge bond length is 2.394(1) Å. The doublet pattern of the band due to the Ge-H bonds (v 2090 and 2104 cm–1) in the IR spectrum is probably associated with nonequivalence of the hydrogen atoms in the molecule.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 315–318, February, 1994. 相似文献
74.
V. S. Ilakin V. G. Shtyrlin A. V. Zakharov A. L. Kon'kin 《Russian Journal of General Chemistry》2002,72(3):349-357
Equilibrium constants of complex formation, rate constants of chemical exchange reactions, and characteristics of electronic absorption spectra for species detected in aqueous solution of copper(II) with triglycine were determined, and conclusions on the structure of the complexes were made. A possibility of H-bond formation between the ammonium group of the zwitter-ionic form of the ligand and the second peptide oxygen in the anionic form of an adjacent ligand was shown. Kinetics and mechanisms of ligand and proton exchanges in solutions of copper(II) bistripeptide complexes with the ligand containing a deprotonated peptide nitrogen atom were studied. A new mechanism was proposed for hydroxide-catalyzed substitution reactions in copper(II) complexes with tripeptides. 相似文献
75.
M. N. Bochkarev B. I. Petrov I. L. Fedyushkin T. V. Petrovskaya V. I. Nevodchikov N. B. Patrikeeva L. N. Zakharov Yu. T. Strucchkov 《Russian Chemical Bulletin》1997,46(2):371-373
Reactions of SmII, TbIII, TmII, YbII, and LuIII iodides with 2,2′-bipyridyllithium in THF afford [Li(THF)4][Ln(bipy) n ] complexes (n=3 or 4) containing trivalent lanthanides. X-ray structural analysis demonstrated that in the crystalline state, the Yb derivative has the ionic structure, [Li(THF)4]+[Yb(bipy)3]?. In THF solutions, the reversible ligand exchange between metal atoms occurs to yield neutral compounds [Ln(bipy) n?1(THF) x ] and [Li(bipy)(THF) y ]. A decrease in the temperature shifts the equilibrium to ionic pairs. 相似文献
76.
T. É. Bezmenova G. I. Khaskin V. I. Slutskii P. G. Dul'nev L. N. Zakharov V. I. Kulishov Yu. T. Struchkov 《Chemistry of Heterocyclic Compounds》1981,17(7):668-672
The reaction of monoalkyl(aryl)dithiocarbamic acid salts with 4-substituted 2-thiolene and 3,4-disubstituted thiolane 1,1-dioxides gave N-alkyl(aryl)thiolano-[3,4-d]thiazolidine-2-thione 5,5-dioxides, the structure of which was proved by x-ray diffraction studies. 1,1-Dioxothiol-3-en-3-yl esters were obtained with salts of dialkyl(heteryl)dithiocarbamic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 907–912, July, 1981. 相似文献
77.
M. I. Kabachnik L. S. Zakharov G. N. Molchanova T. D. Drozdova P. V. Petrovskii 《Russian Chemical Bulletin》1991,40(5):1036-1039
NMR spectroscopy has been used to study the thermal rearrangement of siliconeopentyl esters of phosphorus acids Me3SiCH2OP(O)R2 (I, R=CF3CH2O, PhO, t-BuCH2O, Bu). It has been established that in all cases the products of the rearrangement are the respective silyl esters Me2EtSiOP(O)R2 (II). The thermal rearrangement of (Me3SiCH2O)2P(O)OR (III, R'=Ph, t-BuCH2, Me3SiCH2) is similar. It has been shown that electronic and steric attributes of the substituents R and R on the phosphorus atom are practically without effect on the extent of the thermal rearrangement. The presence of acidic additives, and initiators and inhibitors of radical reactions did not significantly influence the course of the rearrangement. It was concluded that this rearrangement apparently takes place as a result of heterolysis of the C-OP bond and simultaneous nucleophilic attack on the silicon atom by the phosphoryl part of the molecule.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1155–1158, May, 1991. 相似文献
78.
79.
V. V. Zakharov G. P. Bugaeva N. Yu. Andreeva L. B. Romanova L. T. Eremenko 《Russian Chemical Bulletin》1998,47(11):2226-2228
The reduction of 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]nonane-4-carboxylic acid (2) with lithium aluminum hydride and aluminum hydride in THF was studied. A new effective method for preparing 1-bromo-9,9-ethylenedioxypentacyclo[4.3.0.02,5.03,8.04,7]-non-4-ylcarbinol (1) based on reduction of2 with AlH3 under mild conditions was developed. 相似文献
80.
Domenici V Geppi M Veracini CA Zakharov AV 《The journal of physical chemistry. B》2005,109(39):18369-18377
In this work, the rotational-diffusion coefficients D(parallel) and D(perpendicular) for the ferroelectric smectogen (+)-(S)-4-[4'-(1-methylheptyloxy)] biphenyl 4-(10-undecenyloxy)benzoate have been studied by means of 2H NMR spectroscopy in the smectic C phase, using a new theoretical approach (Domenici,V.; Geppi, M.; Veracini, C. A. Chem. Phys. Lett. 2003, 382, 518). The analysis of spin-lattice relaxation times has been performed in terms of the diffusional constant and the activation energy of the internal and overall molecular-reorientational motions, and the results are compared to the smectic A (SmA) phase. Moreover, from the 2H NMR data in the SmA phase, the dielectric permittivity and the dielectric relaxation time functions are investigated using a theoretical approach. The longitudinal and transverse components of the real Rchigammaomega and imaginary chigammaomega (gamma = parallel, perpendicular) parts of the complex susceptibility tensor and the nematic-like rotational-viscosity coefficients, lambda2 and lambda5, are calculated. 相似文献