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61.
T. N. Rostovshchikova V. V. Smirnov D. N. Kharitonov V. B. Rybakov 《Russian Chemical Bulletin》1997,46(10):1736-1740
Tetranuclear copper(I) complexes with organic donor ligands were found to be the best precursors of a catalyst for dichlorobutene
isomerization. The products of interaction between allyl chloride and a tetranuclear triphenylphosphine complex of copper
bromide were investigated by diffraction and spectral analysis. This reaction yields [Cu(PPh3)Br
n
Cl1−n
]4 and complexes containing the products of transformation of both triphenylphosphine and allyl chloride.
Presented at the First Moscow Workshop on Highly Organized Catalytic Systems.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1830–1834, October, 1997. 相似文献
62.
Hubert Schmidbaur Andreas Kolb Edgar Zeller Annette Schier Holger Beruda 《无机化学与普通化学杂志》1993,619(9):1575-1579
On Tris[(trialkylphosphine)gold(I)]oxonium Tetrafluoroborates and Tris[(triphenylphosphine)gold(I)]sulfonium Tetrafluoroborate [Et3PAu]+BF, obtained from Et3PAuCl and AgBF4 in tetrahydrofuran, reacts with KOH (molar ratio 3:1) to give the oxonium salt [(Et3P)Au]3O+BF ( 1 ). The homologous [t(Bu3P)Au]3O+BF ( 2 ) is generated similarly from tBu3PAuCl and Ag2O in the presence of NaBF4 in THF. The composition and identity of these two first tris[(tri alkyl phosphine)gold(I)]oxonium salts have been confirmed by analytical and spectroscopic data. The compounds are useful aurating agents. From the corresponding triphenylphosphine complex and (Me3Si)2S quantitative yields of the sulfonium salt [(Ph3P)Au]3S+BF ( 3 ) are obtained. Its crystal structure features monomeric cations, and in these small Au? S? Au angles indicate significant metal-metal bonding. 相似文献
63.
伯胺N1923、三苯基氧化膦的界面吸附特性 总被引:1,自引:0,他引:1
在25±1℃下考察了N_(1923)(或TPHPO)-CHCl_3/HCl(或HCl-AuCl_4)和N_(1923)-TPhPO-CHCl_3/HCl(或HCl-AuCl_4~-)等6个体系的界面吸附特性,得到了各体系C_(min)、Γ_∞、A_1等界面吸附特性参数。结果表明,N_(1923)的界面活性明显强于TPhPO.当N_(1923)-TPhPO共存时的Γ_∞值较之N_(1923)或TPhPO单独存在时均有增加,可用于解释萃取动力学行为。 相似文献
64.
Kolomnikova G. D. Petrovskii P. V. Sorokin P. V. Dolgushin F. M. Yanovsky A. I. Chizhevsky I. T. 《Russian Chemical Bulletin》2001,50(4):706-715
The reaction of OsCl2(PPh3)3 with [nido-7-R1-8-R2-C2B9H10]K+ produced a series of new exo-nido-osmacarborane complexes exo-nido-5,6,10-[Cl(Ph3P)2Os]-5,6,10-(-H)3-10-H-7-R1-8-R2-7,8-C2B9H6 (1: R1 = R2 = H; 2: R1 = R2 = Me; 3: R1 = R2 = PhCH2; 4: R1 + R2 = 1,2-C6H4(CH2)2; 5: R1 = H, R2 = Me) in which the osmium-containing group is linked to the nido-carborane ligand through three two-electron three-center bonds. Compounds 1—5 are formed as mixtures of symmetric (a) and asymmetric (b) isomers; pure symmetric isomers 2a and 4a were isolated by fractional crystallization, and the mixture of isomers 3a, was quantitatively separated into individual compounds 3a and 3b by column chromatography on silica gel. Detailed analysis of the 31P{1H}, 1H, 11B NMR spectra of 1a,b—5a,b and 2D 1H-1H{11B} and 11B{1H}-11B{1H} NMR spectra of 3a and 3b was performed. The structures of isomers 2a and 4a were confirmed by an X-ray diffraction study. According to the NMR and X-ray diffraction data, the isomerism of exo-nido-complexes 1a,b—5a,b is actually the cis—trans-isomerism of ligand arrangement in the octahedral coordination of the Os atom. 相似文献
65.
The addition of dimethyl acetylenedicarboxylate to isatin derivatives in the presence of triphenylphosphine leading to new highly functionalized γ-spirolactones is reported. 相似文献
66.
67.
开发了一种由顺酐直接加氢高选择性及高转化率制备琥珀酸酐的新方法,研究结果表明:钯三苯基膦催化体系对顺酐加氢具有较高的反应活性.在所考察的反应条件下,此催化剂体系对琥珀酸酐的选择性为100%,无其他副产物生成.并考察了三苯基膦/钯摩尔比,反应温度,氢气压力,催化剂和顺酐浓度对顺酐催化加氢生成琥珀酸酐的影响.在反应条件为PdCl2=125×10-3mol/L,n(顺酐)/n(Pd)≤2000,n(三苯基膦)/n(Pd)=4,T=373~393K,25MPa的氢压下于乙二醇二甲醚溶剂中反应1h以上,可使顺酐的转化率大于90%. 相似文献
68.
The structure of 3-(triphenylphosphoranylidene)naphthalene-1,2,4(3H)-trione was established with the use of IR and13C NMR spectroscopy and quantum-chemical calculations. Reactions of this compound with NH2OH and RNHNH2 involve the carbonyl group in position 1 and a reaction witho-phenylenediamine involves the carbonyl groups in positions 1 and 2.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 373–376, February, 1999. 相似文献
69.
The macrokinetics and products of self-propagating high-temperture synthesis (SHS) in the solid-phase triphenylphosphine—chloramine
system were studied by TGA-DTA, XRD, and31P NMR techniques. The temperature of SHS ignition (59°C), the velocity of reaction waves (1.6–5.0 mm s−1), and the maximum temperature (155–239°C) in the SHS wave were measured. The chemical composition of the product obtained
was established: phosphine oxide, triphenyl-N-(phenylsulfoyl)-phosphinimine, benzenesulfonamide, NaCl, and water. The scheme of chemical reactions occurring during SHS
was proposed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 301–305, February, 1999. 相似文献
70.
The kinetics of the catalytic reaction of styrene with CO and n-butanol in the Pd(dba)2—TsOH—Ph3P system in dioxane (383 Ê) was studied. The initial rates of accumulation of regioisomeric products (butyl 2- and 3-phenylpropionates) were measured as functions of the CO pressure, reactant concentrations, and the catalytic system components. A kinetic model of the process and a hydride mechanism with the HPd(Ph3P)3
+ cationic complex acting as a key intermediate were proposed. 相似文献