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41.
Alessandro Fumagalli Maria Carlotta Malatesta Michele Vallario Gianfranco Ciani Massimo Moret Angelo Sironi 《Journal of Cluster Science》2001,12(1):187-200
The reaction of Ru3(CO)12 and [Ir(CO)4]- (as [PPh4]+ or [N(PPh3)2]+ salts) yields the anion [Ru3Ir2(CO)14]2- (1) which has been found to derive from the intermediate [Ru3Ir(CO)13]- anion. Treatment of (1) with acids gives the conjugated hydrido species [Ru3Ir2(CO)14H]- (2). The two anions were characterized by single-crystal X-ray diffraction of their [PPh4]+ salts. [PPh4]2[Ru3Ir2(CO)14]: space group C2/c, Z=4, a=22.121(5) Å, b=10.546(5) Å, c=25.931(5) Å, =103.870(5)°, R=0.052 and Rw=0.130 for 3128 independent reflections with I>2(I ). [PPh4][Ru3Ir2(CO)14H]: space group P21/c, Z=8, a=22.833(5) Å, b=13.893(5) Å, c=25.810(5) Å, =92.650(5)°, R=0.070 and Rw=0.150 for 12141 independent reflections with I>2(I). Both anions 1 and 2 have a trigonal bipyramidal metal frame. There are two independent anions in the asymmetric unit of 2 differing in their ligand stereochemistry. 相似文献
42.
Maher Izaaryene Hans Reuter 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1364-1366
Abstract The title compound has been prepared via self-assembly of an RSn and VO source. In the solid, the cation and anion form an intimate ion pair via a V?O?Sn bond expanding the coordination sphere at tin from square-pyramidal to trigonal-prismatic. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT 相似文献
43.
Tuan‐Anh Nguyen Julien Roger Houssein Nasrallah Vincent Rampazzi Sophie Fournier Hlne Cattey E. Daiann Sosa Carrizo Paul Fleurat‐Lessard Charles H. Devillers Nadine Pirio Dominique Lucas Jean‐Cyrille Hierso 《化学:亚洲杂志》2020,15(18):2879-2885
Di‐tert‐butylated‐bis(phosphino)ferrocene ligands bearing phosphino substituents R (R=phenyl, cyclohexyl, iso‐propyl, mesityl, or furyl) allow tuning the selective formation of Au(I) halide complexes. Thus, dinuclear linear two‐coordinate, but also rare mononuclear trigonal three‐coordinate and tetrahedral four‐coordinate complexes were formed upon tuning of the conditions. Both Au(I) chloride and rarer Au(I) iodide complexes were synthesized, and their X‐ray diffraction analysis are reported. The significance of the control of structure and nuclearity in Au(I) complexes is further illustrated herein by its strong effect on the efficiency and selectivity of gold‐catalysed cycloisomerization. Cationic linear digold(I) bis(dicyclohexylphosphino) ferrocenes outperform other catalysts in the demanding regioselective cycloisomerization of enyne sulphonamides into cyclohexadienes. Conversely, tetrahedral and trigonal cationic monogold(I) complexes were found incompetent for enyne cycloaddition. We used the two‐coordinate linear electron‐rich Au(I) complex 2 b (R=Cy) to extend the scope of selective intramolecular cycloaddition of different 1,6‐enyne sulfonylamines with high activity and excellent selectivity to the endo cyclohexadiene products. 相似文献
44.
《应用有机金属化学》2017,31(10)
Six new heteroleptic phenylantimony(III) derivatives containing substituted oximes and dithiocarbamate moieties of the type (where R = ─C6H5, X = ─CH3 ( 2a ); R = ─C6H4CH3, X = ─CH3 ( 2b ); R = ─C6H4Cl, X = ─CH3 ( 2c ); R = ─C6H4Br, X = ─CH3 ( 2d ); R = ─C6H4OH, X = ─H ( 2e ); R(X)C = ( 2f )) have been synthesized by the reactions of phenylantimony(III) dichloride with the sodium salt of substituted oximes and dithiocarbamate moiety in unimolar ratio with stirring in dichloromethane. All these newly synthesized derivatives have been characterized using physicochemical and elemental analyses. Structures have been proposed on the basis of infrared, 1H NMR, 13C NMR and LC–MS spectral studies and molecular modelling. In these derivatives the oxime behaves in an unidentate manner whereas dithiocarbamate behaves in a monofunctional anisobidentate manner. Pseudo‐trigonal bipyramidal (ψ‐TBP) geometry around the antimony metal centre is proposed for these phenylantimony(III) heteroleptic derivatives. The geometry of a representative complex has been optimized through molecular modelling. These newly synthesized derivatives were screened against Bacillus subtilis (Gram‐positive) and Escherichia coli (Gram‐negative) bacteria to evaluate their antibacterial potential. The structure–activity relationship for antibacterial activity among the four derivatives 2a , 2c , 2e and 2f is discussed. 相似文献
45.
Reaction of [Mn(bpm)2]2+ with K3[Co(CN)5(NO)] produces a cyano-bridged bimetallic compound,{[Mn(bpm)2]1.5[Co(CN)5(NO)]}·2H2O (1), (bpm=bis(1-pyrazol)methane). Compound 1 crystallizes in the tetragonal space group P43212 with a=1.305 08(8) nm, b=1.305 08(8) nm, c=4.386 7(5) nm, V=7.471 5(10) nm3, and Z=8. Complex 1 exhibited a structure of a pentanuclear cluster. The Mn2+ ions each are surrounded by bpm ligands, forming the [Mn(bpm)2]2+ cation fragment. Three cation fragments are connected to the two anion fragments, [Co(CN)5(NO)]3-, by cyanide bridges. The five metal ions form a trigonal bipyramidal structure, where the Mn2+ ions are situated in the equatorial plane and the Co2+ ions are on both sides of the plane. As a semirigid ligand, bpm is more flexible than rigid 2,2′-bipydine, and it results in the two different configurations in the [Mn(bpm)2]2+ cation fragment. CCDC: 635764. 相似文献
46.
47.
Ngoh Khang Goh Chit Kay Chu Lian Ee Khoo Deborah Whalen George Eng Frank E. Smith Rosemary C. Hynes 《应用有机金属化学》1998,12(6):457-466
The methods of synthesis, elemental analysis, IR and NMR spectroscopic data and fungicidal activity against Ceratocystis ulmi are reported for a series of triorganotin esters of N-arylidene-ω-amino acids of general formula R3SnOCO(CH2)nN = CHAr (R = Ph, n-Bu; Ar = 2-HOC6H4, 2-HOC10H6; n = 1, 2, 3 and 5). The crystal structures for two of the compounds, tributyltin N-2-hydroxynaphthalidene glycinate ( 1 ) and tributyltin N-2-hydroxynaphthalidene-β-alaninate ( 2 ), have been determined. Although both of these compounds have a trans-R3SnO2 structure, in compound 1 the carboxylate group is monodentate and the fifth coordination position around the tin atom is taken up by a coordinated phenolic group, whereas in 2 the carboxylate group is bridging. These two examples thus correspond to the two different structures reported for trans-R3SnO2 complexes. Both compounds were found to be active against Ceratocystis ulmi, but there was no significant difference in their levels of biological activity against this particular fungus. Apart from compound 1 , the other tributyltin compounds reported are believed to adopt the carboxylate bridging mode shown by compound ( 2 ). Crystal data: for 1 , crystals monoclinic, space group P 21/ c , a = 12.9435(11) Å, b = 13.5769(10) Å, c = 15.7715(12) Å, β = 108.919(6)°, Z = 4, R f = 0.046 and R w = 0.058 for 1448 significant reflections; for 2 , crystals monoclinic, space group C 2/ c , a = 24.588(14) Å, b = 9.733(3) Å, c = 27.611(12) Å, β = 113.49(4)°, Z = 8, R f = 0.053 and R w = 0.069 for 3822 significant reflections. © 1998 John Wiley & Sons, Ltd. 相似文献
48.
ABSTRACTThe ferroelastic phase transitions in KFe(MoO4)2 have been studied by means of polarized light microscopy. The crystal undergoes a sequence of ferroelastic phase transitions. It has been found that the second transition consists of two transitions separated by the temperature interval of about 0.4 K. Both these transitions are of the first order and are evidenced through a phase front passing, without the domain structure rebuilding. The disposition of optical indicatrix axes ng, nm has been established, and the birefringence has been measured in the plane (0001) in the temperature range covering all ferroelastic phases. From temperature studies of the morphic birefringence, a critical exponent of the order parameter has been estimated. 相似文献
49.
Jií ejka Jií Sejkora Jakub Plil Silmarilly Bahfenne Sara J. Palmer Ray L. Frost 《Journal of Raman spectroscopy : JRS》2010,41(4):459-464
Raman and infrared spectroscopies were used to characterise two samples of triclinic čejkaite Na4[UO2(CO3)3] and its synthetic trigonal analogue. The ν3 (UO2)2+ mode is not Raman active, whereas both the ν3 and ν1 (UO2)2+ modes are infrared active. U O bond lengths in uranyls were calculated from the spectra obtained and compared with bond lengths derived from crystal structure analyses. From the higher number of bands related to the uranyl and carbonate vibrations, the presence of symmetrically distinct (UO2)2+ and (CO3)2− units in both structures is proposed. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
50.
K. C. Kumara Swamy Sarah D. Burton Joan M. Holmes Roberta O. Day Robert R. Holmes 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):437-455
Abstract A review on pertinent information on cyclic oxyphosphoranes is presented. Recent X-ray structures and variable temperature 1H NMR investigations of cyclic pentaoxyphosphoranes reveals a preference for a boat conformation for saturated six-membered rings in apical-equatorial orientations of trigonal bipyramids. These studies include five-, six-, and seven-membered rings and show that the solid state structures are retained in solution. Apical-equatorial ring pseudorotations are more facile for five-membered rings, whereas ligand exchange via diequatorial ring placement is more facile for the larger rings. The importance of the apical-equatorial ring orientation for phosphorinanes appearing as trigonal bipyramidal intermediates in enzymatic reactions of cyclic AMP analogs is emphasized. 相似文献