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151.
Thomas CM Mafua R Therrien B Rusanov E Stoeckli-Evans H Süss-Fink G 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(15):3343-3352
The new diphosphine ligands Ph(2)PC(6)H(4)C(O)X(CH(2))(2)OC(O)C(6)H(4)PPh(2) (1: X=NH; 2: X=NPh; 3: X=O) and Ph(2)PC(6)H(4)C(O)O(CH(2))(2)O(CH(2))(2)OC(O)C(6)H(4)PPh(2) (5) as well as the monophosphine ligand Ph(2)PC(6)H(4)C(O)X(CH(2))(2)OH (4) have been prepared from 2-diphenylphosphinobenzoic acid and the corresponding amino alcohols or diols. Coordination of the diphosphine ligands to rhodium, iridium, and platinum resulted in the formation of the square-planar complexes [(Pbond;P)Rh(CO)Cl] (6: Pbond;P=1; 7: Pbond;P=2; 8: Pbond;P=3), [(Pbond;P)Rh(CO)Cl](2) (9: Pbond;P=5), [(P-P)Ir(cod)Cl] (10: Pbond;P=1; 11: Pbond;P=2; 12: Pbond;P=3), [(Pbond;P)Ir(CO)Cl] (13: Pbond;P=1; 14: Pbond;P=2; 15: Pbond;P=3), and [(Pbond;P)PtI(2)] (18: Pbond;P=2). In all complexes, the diphosphine ligands are trans coordinated to the metal center, thanks to the large spacer groups, which allow the two phosphorus atoms to occupy opposite positions in the square-planar coordination geometry. The trans coordination is demonstrated unambiguously by the single-crystal X-ray structure analysis of complex 18. In the case of the diphosphine ligand 5, the spacer group is so large that dinuclear complexes with ligand 5 in bridging positions are formed, maintaining the trans coordination of the P atoms on each metal center, as shown by the crystal structure analysis of 9. The monophosphine ligand 4 reacts with [[Ir(cod)Cl](2)] (cod=cyclooctadiene) to give the simple derivative [(4)Ir(cod)Cl] (16) which is converted into the carbonyl complex [(4)Ir(CO)(2)Cl] (17) with carbon monoxide. The crystal structure analysis of 16 also reveals a square-planar coordination geometry in which the phosphine ligand occupies a position cis with respect to the chloro ligand. The diphosphine ligands 1, 2, 3, and 5 have been tested as cocatalysts in combination with the catalyst precursors [[Rh(CO)(2)Cl](2)] and [[Ir(cod)Cl](2)] or [H(2)IrCl(6)] for the carbonylation of methanol at 170 degrees C and 22 bar CO. The best results (TON 800 after 15 min) are obtained for the combination 2/[[Rh(CO)(2)Cl](2)]. After the catalytic reaction, complex 7 is identified in the reaction mixture and can be isolated; it is active for further runs without loss of catalytic activity. 相似文献
152.
Ochsenbein ST Murrie M Rusanov E Stoeckli-Evans H Sekine C Güdel HU 《Inorganic chemistry》2002,41(20):5133-5140
The preparation of two new compounds containing the cluster [Ni(21)(cit)(12)(OH)(10)(H(2)O)(10)](16-) is presented, together with a detailed magnetic investigation of one of the compounds. We found that this cluster shows an unexpected stability and that it exists as different stereoisomers. Compound 1 contains the achiral cluster with a Delta-Lambda configuration, and compound 2 contains a pair of enantiomeric clusters with the configurations Delta-Delta and Lambda-Lambda, respectively. Magnetic measurements of 1 in the millikelvin range were necessary to determine the spin ground state of S = 3, and they also revealed a magnetic anisotropy within the ground state. A frequency-dependent out-of-phase signal was found in alternating current susceptibility measurements at very low temperatures, which indicates a slow relaxation of the magnetization. Thus, individual molecules are acting as single magnetic units, which is a rare phenomenon for nickel clusters. The energy barrier exhibited by compound 1 has been calculated to be 2.9 K. 相似文献
153.
Eduard B. Rusanov Alexander N. Chernega Mark I. Povolotskii 《Journal of chemical crystallography》1999,29(12):1277-1280
The crystal and molecular structure of P-(2,4,6-tri-tert-buthylphenyl)-phenylmethylene (phenylsulfonylimino)-35-phosphorane, 2,4,6-But
3-C6H2-P(=CHPh)(=N--SO2Ph), has been determined. Crystal data: triclinic,
, a = 9.472(5), b = 11.427(5), c = 13.684(5) Å, = 90.61(3), = 101.21(4), = 97.02(4)°, V = 1441.1 Å3, Z = 2, D
c = 1.20 g cm–3. The observed in 1 noticeable elongation of the P=N bond 1.563(3) Å and shortening of the P=C bond 1.617(3)Å have been discussed in terms of the electron withdrawing ability of substituents on the basis of ab initio (HF/6–31+G**) calculations of the model systems. 相似文献
154.
Alexander N. Chernega Eduard B. Rusanov Mark I. Povolotskii 《Journal of chemical crystallography》1999,29(4):475-480
The crystal and molecular structure of 1-phenyl-1-dimethylamino-4,4-bis(trimethylsilyl)-2-aza-33-phosphabutadiene-1,3, Me2N(Ph)C=N—P=C(SiMe3)2 (1), has been determined. Crystal data: triclinic, P1¯, a = 8.975(4), b = 10.001(5), c = 12.440(6) Å, = 79.04(4), = 77.98(4), = 73.07(4)°, V = 1034.7 Å3, Z = 2, and D
c
= 1.08 g cm–3. The main geometrical parameters of 1 as well as ab initio (HF/6-31+G**) calculations of the model systems show no clear evidence of high efficiency of the (C=N)— (P=C) conjugation. 相似文献
155.
Demchenko A. M. Bova S. I. Chumakov V. A. Krasovskii A. N. Rusanov E. B. Chernega A. N. Lozinskii M. O. 《Russian Journal of General Chemistry》2001,71(11):1759-1763
Substituted phenacyl bromides react with 2-anilino-5,6-dihydro-4H-1,3-thiazine at the exocyclic nitrogen atom and with 2-benzylamino-5,6-dihydro-4H-1,3-thiazine at the nitrogen atom in the ring. The structure of the reaction intermediates was elucidated, and their cyclization into 1-benzyl-2-aryl-6,7-dihydro-5H-imidazo[2,1-b][1,3]thiazinium bromides was performed. 相似文献
156.
M. L. Keshtov A. L. Rusanov P. V. Petrovskii A. N. Shchegolikhin N. M. Belomoina S. V. Keshtova A. A. Kirillov V. V. Kireev 《Russian Chemical Bulletin》1999,48(10):1942-1945
The Diels-Alder reactions of 4,4′-bis(2,4,5-triphenylcyclopentadienon-3-yl)benzophenone with carboxylic anhydrides containing
multiple carbon-carbon bonds afforded novel tetracarboxylic dianhydrides.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1966–1969, October, 1999. 相似文献
157.
Anton V. Tverdokhlebov Alexander P. Gorulya Alexander N. Kostyuk Eduard B. Rusanov 《Tetrahedron》2006,62(39):9146-9152
An interaction of 2-[cyclohexyl(methyl)amino]benzaldehydes with substituted acetonitriles X-CH2CN (X=CN, Tos, hetaryl) was found to yield 1-methyl-1,2,3,4-tetrahydrospiro(quinoline-2,1′-cyclohexane)-3-carbonitriles. The corresponding spiroquinoline-2,1′-cyclopentane analogues were obtained similarly starting from 2-[cyclopentyl(methyl)amino]benzaldehydes. The reaction was assumed to proceed via initial Knoevenagel condensation and further ring closure of the formed adduct according to the tert-amino effect mechanism. The structure of the prepared compounds was confirmed unambiguously by X-ray crystallographic study. 相似文献
158.
159.
Ohne Zusammenfassung 相似文献
160.
Russian Chemical Bulletin - 相似文献