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81.
Zakharova L Valeeva F Zakharov A Ibragimova A Kudryavtseva L Harlampidi H 《Journal of colloid and interface science》2003,263(2):597-605
Surface tension measurements and the kinetic study of the basic hydrolysis of ethyl p-nitrophenyl chloromethyl phosphonate were used to examine the structural behavior and catalytic activity of the cethyltrimethylammonium bromide (CTAB)-polyoxyethylene (10) oleyl ether, C(18)H(35)(OCH(2)CH(2))(10)OH (Brij 97)-water mixed micellar system. Application of the regular solution model to the experimental data yields the value of the interaction parameter beta as -4.6, which indicates an attractive interaction of the surfactants in the mixed micelle and reflects synergistic solution behavior of the mixture. The mixed micellar composition is found to be enriched in the surfactant with the lower critical micelle concentration (cmc). In the kinetic study a nonmonotonic change in the pseudo-first-order rate constant of basic hydrolysis of the substrate is observed with increasing mole fraction of nonionic surfactant. The pseudophase micellar model reveals that the concentration factor mainly contributes to the catalytic effect, while the microenvironmental factor plays a negative role. 相似文献
82.
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
83.
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
84.
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
85.
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
86.
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
87.
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
88.
1,10-邻菲咯啉-铜(Ⅱ)-L-蛋氨酸配合物的合成、表征及其分子结构 总被引:10,自引:0,他引:10
The complex [Cu(L-met)(phen)(H2O)]NO3·H2O has been synthesized and investigated by elemental analysis, molar conductivity, spectroscopic and X-ray diffraction methods, where phen=1,10-phenanthroline and L-met=L-methioninate group. The complex crystallized in the monoclinic space group P21 with a=12.053(2)?, b=6.886(1)?, c=13.385(3)?, β=113.59(3)°, V=1018.1(3)?3, Z=2,Dc=1.598g·cm-3, μ=1.223mm-1, F(000)=506, R1=0.0306, and wR2=0.0742. The copper(Ⅱ) atom is ligated in a distorted square-pyramidal geometry by two nitrogen atoms of one phen and the amino nitrogen atom , one carboxylate oxygen atom of L-met in the base plane, and an aqua at the apical position. A one-dimensional chain configuration formed by the hydrogen-bonding and weak Cu-O (the uncoordinated carboxyl oxygen atom) coordination interactions be-tween neighboring [Cu(L-met)(phen)(H2O)]+ cations. CCDC: 183368. 相似文献
89.
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
90.