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151.
采用溶胶浸渍模板法制备了有序多孔的氧化钛(TiO2)和氧化锌(ZnO)薄膜。首先,在洁净的玻璃基片上通过浸渍-提拉工艺组装有序的聚苯乙烯微球(PS)阵列模板;然后再采用溶胶浸渍法将TiO2和ZnO溶胶灌充到PS模板微球的间隙内;最后通过煅烧去除PS而得多孔薄膜。采用SEM观察了薄膜的表面形貌,并用XRD对薄膜的性能进行了表征。结果表明,溶胶的浓度对薄膜形貌有着显著的影响。经煅烧后,TiO2和ZnO薄膜分别为锐钛矿和六方纤锌矿结构。此外,对模板的组装及溶胶的灌注过程进行了分析。 相似文献
152.
A.N. Nesmeyanov N.A. Ustynyuk L.N. Novikova V.G. Andrianov Yu.T. Struchkov Yu.A. Ustynyuk Yu.F. Oprunenko Yu.N. Luzikov 《Journal of organometallic chemistry》1982,226(3):239-250
Alkylation of K[η5-C9H7Cr(CO)3] (Xa) with CH3I and C6H5CH2Br leads to σ-alkyl derivatives of η5-C9H7Cr(CO)3Alk type. These complexes undergo innersphere “ricochet” rearrangement, with the alkyl group being shifted to the endo position at C(1) and the chromium tricarbonyl group shifted to the benzene nucleus. The structure of the product of such a rearrangement in the case of η5-C9H7(CO)3CrCH2C6H5, i.e. (1-benzyl-3a,4-7,7a-η6-indene)chromium tricarbonyl (XVIII), is established by a low temperature X-ray study, indicating an endo position for the benzyl radical.On alkylation of equilibrium tautomeric mixtures of η5- and η6-fluorenylchromium tricarbonyl anions XIa ? XIb under similar conditions, the η5-anion (Xa) yields a σ-alkyl derivative, which is rearranged to (9-endo-alkyl-1-4,4a,9a-η6-fluorene)chromium tricarbonyl. Electrophilic attack of the η6-anion (XIb) takes place on the outer side at C(9) and leads to a corresponding 9-exo-alkyl derivative. 相似文献
153.
E. A. Katayev G. D. Pantos V. M. Lynch J. L. Sessler M. D. Reshetova Yu. A. Ustynyuk 《Russian Chemical Bulletin》2005,54(1):165-172
Three new macrocyclic Schiff bases containing an amine or amide structural fragment along with imine groups were synthesized by condensation of 2,6-bis(2-aminophenyliminomethyl)pyridine (1) and N, N’-bis(2-aminophenyl)pyridine-2,6-dicarboxamide (2) with 2,5-diformylpyrrole (3) and 2,2-bis(5-formylpyrrol-2-yl)propane (4). The reaction of compound 1 with 3 proceeds abnormally and is accompanied by redox disproportionation of compound 1 in the first step. The structure of the macrocyclic product of this reaction was established by X-ray diffraction analysis. Spectrophotometric titration showed that hybrid macrocycle 10, which was prepared by condensation of compound 2 with 4, possesses the properties of an anion receptor and selectively binds hydrosulfate and dihydrophosphate anions in the presence of bromide and nitrate anions. The structures of 10 and its adduct with the hydrosulfate anion were calculated by density functional theory.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 161–168, January, 2005. 相似文献
154.
Ustynyuk L. Yu. Ustynyuk Yu. A. Laikov D. N. Lunin V. V. 《Russian Chemical Bulletin》2001,50(11):2050-2053
Model reactions of silica-supported zirconium hydrides (Si—O—)3ZrH and (Si—O—)2ZrH2 with methane, resulting in cleavage of a C—H bond in the methane molecule and the formation of (Si—O—)3ZrCH3 and (Si—O—)2Zr(H)CH3 as products were studied using the DFT approach with the PBE density functional. The processes proceed as bimolecular reactions without preliminary formation of agostic complexes. According to calculations, zirconium dihydrides (Si—O—)2ZrH2 are more reactive toward the methane C—H bonds than zirconium monohydrides (Si—O—)3ZrH. The calculated activation energies of the reactions with participation of zirconium dihydrides (Si—O—)2ZrH2 are in better agreement with the known experimental data for the Yermakov—Basset catalytic system. 相似文献
155.
N. G. Akhmedov E. A. Katsman S. G. Malyugina V. I. Mstislavsky Yu. F. Oprunenko V. A. Roznyatovsky Yu. A. Ustynyuk A. S. Batsanov N. A. Ustynyuk 《Russian Chemical Bulletin》1997,46(10):1769-1786
The reaction of phenalene with Cr(CO)3Py3/BF3·OEt2 afforded a mixture of two isomeric complexes, tricarbonyl(6a,7-9,9a,9b-·6-phenalene)chromium (1) and tricarbonyl(3a,6a,9b,4-6-·6-phenalene)chromium (2). Deprotonation of the mixture of compounds1 and2 followed by treatment with MeI, BunI, or D2O gave complexesexo-1-R-1 (3–5: R=Me (3), Bun (4), or D (5)). The molecular geometry of complex3 was established by X-ray structural analysis. Heating of complex5 in toluene or C6F6 at 90–110 °C resulted in redistribution of deuterium among positionsexo-1,endo-1, and 3 in the resulting complexes of types1 and2
via sigmatropic shifts of the H
exo
and H
endo
atoms in the nonaromatic ring as well asvia inter-ring migrations of the tricarbonylchromium group. In the case of3, the methyl label is distributed among positionsexo-1 and3 to form isomeric complexes with similar structures (exo-1-Me-2 (6), 3-Me-2 (7), and 3-Me-1 (8), respectively)via processes analogous to those observed in the case of isomerization of compound5 (except for migration of the H
exo
atom). The mechanisms of these rearrangements are discussed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1863–1880, October, 1997. 相似文献
156.
Ustynyuk Yu. A. Borisova N. E. Nosova V. M. Reshetova M. D. Talismanov S. S. Nefedov S. E. Aleksandrov G. A. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2002,51(3):488-498
Condensation of 4-tert-butyl-2,6-diformylphenol with 1,2-diaminobenzene in ethanol is accompanied by partial reduction of the azomethine double
bonds to form symmetrical macrocyclic Schiff"s base containing the alternating >C=N and >CH—NH fragments. In solution, this
compound exists as the only isomer in which two endocyclic hydrogen atoms are bound to the oxygen atoms of the phenol groups
and two other endocyclic H atoms are attached to the nitrogen atoms of the CH2—NH fragments. All endocyclic protons are involved in hydrogen bonding and undergo rapid exchange with each other at room
temperature. In the crystal, the planar macrocyclic molecules are arranged in closely packed stacks. The steric hindrances
resulting from overlapping of the bulky tert-butyl groups are eliminated through rotation of the molecules with respect to each other in the adjacent layers. Study of
the potential energy surface for the Schiff"s base under consideration by the DFT method demonstrated that the structure corresponding
to the global minimum is similar to that found in solution. However, the isolated molecule is nonplanar, its macrocycle adopting
a ladder conformation. The local minimum on the potential energy surface whose energy is 2.6 kcal mol–1 higher than that of the global minimum corresponds to the zwitterionic structure in which all four endocyclic hydrogen atoms
are attached to the nitrogen atoms and the macrocycle adopts a tub conformation. Flattening of the ring is considered as a
consequence of stacking interactions between the molecules in the crystal. 相似文献
157.
Chernyadyev A. Yu. Ustynyuk Yu. A. Yazev O. V. Kataev E. A. Reshetova M. D. Sidorov A. A. Aleksandrov G. G. Ikorskii V. N. Novotortsev V. M. Nefedov S. E. Eremenko I. L. Moiseev I. I. 《Russian Chemical Bulletin》2001,50(12):2445-2450
The reaction of pyrrole-2,5-dicarbaldehyde (1) with o-phenylenediamine (2) in anhydrous EtOH afforded a [1+1]-condensation product, viz., Schiff"s base. The structure of the latter was established by NMR spectroscopy and X-ray diffraction analysis. The reaction of this product or a mixture of 1 and 2 with Ni9(n-OOCBut)12(HOOCBut)4(4-OH)3(3-OH)3 in MeCN in the presence of AcOH gave rise to an antiferromagnetic binuclear complex. According to the X-ray diffraction data, the macrocycle in the latter complex is a [2+2]-condensation product of compounds 1 and 2, eff ranging from 0.569 to 2.614 B (2—301 K), –2J = 360 cm–1. The Ni2(OAc)2 fragment is located in the central cavity of the macrocycle. The structures of the condensation products are discussed based on the results of DFT quantum-chemical calculations. 相似文献
158.
N. P. Glinskaya I. P. Gloriozov I. E. Nifant'ev Yu. A. Ustynyuk 《Russian Chemical Bulletin》1993,42(5):810-817
Energies, geometries, and electronic structures of structural isomers of 4,4,8,8-tetramethyl-4,8-disila-3a,4,4a,8-tetrahydro-sym-indacene as well as some transition states for the intramolecular metallotropic rearrangements of these compounds were calculated using the semiempirical quantum-chemical INDO and MNDO methods. The applicability of the MINDO/3, INDO, and MNDO methods for describing l-silyl derivatives of cyclopentadienes was tested on model compounds R3SiC5H5, where R is Me or H.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 859–865, May, 1993. 相似文献
159.
Yu.A. Strelenko Yu.G. Bundel F.H. Kasumov V.I. Rozenberg O.A. Reutov Yu.A. Ustynyuk 《Journal of organometallic chemistry》1978,159(2):131-135
The 199Hg chemical shifts in a number of benzylmercuric chlorides containing methyl substituents in various positions of the benzene nucleus are studied by the heteronuclear 1H-{199Hg} double resonance technique. Meta- and para-methyl substituents are shown to have no pronounced action on the shielding whereas ortho-methyl groups each shift the signal by 30 ppm downfield. The observed effect is due to an increase in the population of conformers with the CHg bond lying out of the aromatic cycle plane. The departure from planarity favours conjugation between the electrons of the CHg bond and the π-electronic system of the ring. The J(1H199Hg) and J(13C199Hg) coupling constant values obtained in this work confirm the latter conclusion. 相似文献
160.
Yu. K. Grishin I. P. Gloriozov S. M. Gerdov V. A. Roznyatovsky L. L. Frolova A. V. Kuchin Yu. A. Ustynyuk 《Russian Chemical Bulletin》2008,57(8):1689-1696
The selectivity of deuterium distribution between the nonequivalent positions in 3-carene (1), 4-α-acetyl-2-carene (2), and 4-(1-hydroxyethyl)-2-carene (3) has been measured by 2H-{1H} NMR spectroscopy at the natural abundance of deuterium. These “H/D-isotope portraits” were shown to be typical of terpenes
and terpenoids produced in plants via the biosynthetic DXP pathway. The mechanism of acylation of 1 was studied by the density functional theory method (PBE functional, TZ2p basis set). The six-membered ring in compound 1 is planar. However, the endo attack of electrophiles on this ring is more favorable both kinetically and thermodynamically. It was shown both experimentally
and theoretically that the elimination of a hydrogen atom in the second reaction step proceeds stereoselectively at the C(2)
atom from the anti position with respect to the three-membered ring and occurs with pronounced nucleophilic assistance from the carbonyl group.
For Part 2, see Ref. 1.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1657–1664, August, 2008. 相似文献