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11.
S. J. Sabounchei V. Jodaien S. Samiee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):473-481
Complexes of the type NBu 4 MCl 3 PR 3 R=P.Tolyl,Ph,Bu) (M = Pt, Pd) are prepared by the reaction of MCl 2 or K 2 [MCl 4 ] by phosphine ligands. Addition of NBu 4 Br or NBu 4 I to these compounds, in dichloromethane results in a redistribution of halogens and formation of all six isomers of the type MBr 3 ?XClXPR 3 X= 0, 1, 2, and 3 which have been identified by 31 P- 1 H NMR spectroscopy. The intensities show that the products are proportional to the statistical distribution. 相似文献
12.
Malek Taher Maghsoodlou Sayyed Mostafa Habibi Khorasani Nourollah Hazeri Mahmoud Nassiri Reza KaKaei Ghasem Marandi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):553-560
Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, in the presence of strong NH-acids, such as imidazole, 2-methylimidazole, 4-methylimidazole, 2-ethylimidazole, benzimidazole, and 5,6-dimethylbezimidazole. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group. 相似文献
13.
Malek Taher Maghsoodlou Nourollah Hazeri Sayyed Mostafa Habibi Khorasani Aqil Ghulame Shahzadeh Mahmoud Nassiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):913-919
Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates in the presence of strong NH acids, such as indole and 2-methyl indole, 3-methyl indole, and 5-boromo indole. These stable ylides exist in a solution as a mixture of two geometrical isomers as a result of the restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group. 相似文献
14.
Mohammad Anary-Abbasinejad Nasim Shams Alireza Hassanabadi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1823-1829
The reaction between arylglyoxalmonohydrates, dialkyl acetylenedicarboxylates, and triphenylphosphine is described as a simple and efficient method for the synthesis of 5-hydroxy-4-aryl-2,5-dihydrofuran-2,3-dicarboxylate derivatives. 相似文献
15.
Issa Yavari Abdolali Alizadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1003-1008
Stable diastereomeric ethyl 1-benzoyl-6-(bromomethyl)-2,2,2,4-tetra- phenyl-3,7-dioxa-2λ 5 -phosphabicyclo[3.2.0]hept-4-ene-6-carboxylate was obtained in 98% yield from the reaction between dibenzoylacetylene as electron-deficient acetylenic compound, and ethyl 3-bromopyruvate in the presence of triphenylphosphine in dry ether. 相似文献
16.
Theodore D. Sideris Panayiotis V. Ioannou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1017-1030
The scope of ascorbic acid/iodine and triphenylphosphine/iodine in methanol for the direct reduction of arsenic(V) compounds having the As[dbnd]O group has been investigated. Ascorbic acid/iodine reduces arsonic acids, diphenylarsinic acid (but not dimethylarsinic acid), and triphenylarsine oxide. The rates of reduction depend on the electronic effects of the ligands bound to arsenic and on the hydrogen-bonding strength of the species, when present. When the As(V) compound has an [sbnd]NH 2 or an [sbnd]NH 3 + group, the reduction product reacts with a ketonic form of dehydroascorbic acid, giving condensation product(s). Triphenylphosphine/iodine reduced slowly the zwitterionic o-aminophenylarsonic acid but reduced faster the hydrochloric acid salt of the same acid. It reduced dimethylarsinic acid as well because the powerful electron-withdrawing Ph 3 P +coordinated to As[dbnd]O seems to outweigh the electronic and hydrogen bonding effects. 相似文献
17.
Palanisamy Jamuna Rani Subbiah Thirumaran Samuele Ciattini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):778-789
Abstract Six new nickel complexes of two dithiocarbamate ligands (cyfdtc = N-cyclohexyl-N- furfuryldithiocarbamate and bztpedtc = N-benzyl-N-[2-thiophenylethyl]dithiocarbamate) namely, (Ni[cyfdtc]2) (1), (Ni[bztpedtc]2) (2), (Ni[cyfdtc][NCS][PPh3]) (3), (Ni[bztpedtc] [NCS][PPh3]) (4), (Ni[cyfdtc][PPh3]2)ClO4 (5), and (Ni[bztpedtc][PPh3]2)ClO4 (6) have been prepared and characterized using IR, electronic, and NMR (1H and 13C) spectra. A single crystal X-ray structural analysis was carried out for complex 3 and showed that nickel is in a distorted square planar arrangement with the NiS2PN chromophore. The shift in νC?N of the heteroleptic complexes to higher frequencies compared with the parent complex is assigned to mesomeric delocalization of electron density from the dithiocarbamate ligand toward the metal atom, which increases the contribution of polar thioureide form in mixed ligand complexes. Electronic spectral studies suggest square planar geometry for the complexes. In the 13C NMR spectra, the upfield shift of NCS2 carbon signal for 3 and 4 from the chemical shift value of 1 and 2 is due to effect of PPh3 on the mesomeric drift of electron density toward nickel throughout thioureide C?N bond. 相似文献
18.
Malek Taher Maghsoodlou Norollah Hazeri Ghafar Afshari Uranous Niroumand 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2681-2689
The reaction of triphenylphosphine with dialkyl acetylenedicarboxylates in the presence of a strong SH-acid or NH-acid, such as 2-mercaptobenzoxazole and 2-benzoxazolinone, has been studied. In some cases, stable phosphorus ylides are obtained in excellent yields. The ylide moiety of these compounds is strongly conjugated with the adjacent carbonyl group, and the rotation about the partial double bond in (E) and (Z) geometrical isomers is slow on the NMR time scale at an ambient temperature. Thus, these exist as a mixture of geometrical isomers. 相似文献
19.
R. Hekmatshoar S. Souri M. Rahimifard 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1605-1609
Protonation of the highly reactive intermediate produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylate 1a–c by methyl-2-hydroxy-3-naphthoate lead to vinyl triphenylphosphonium salts which undergo aromatic electrophilic substitution reaction with phenolate-conjugated base to produce 2a–c. 相似文献
20.
Batool Akhlaghinia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1783-1786
Tetrahydropyranyl ethers were converted to their corresponding alkyl cyanides efficiently by using the triphenylphosphine/ 2,3-dichloro-5,6-dicyanobenoquinone/n-Bu 4 NCN system in refluxing acetonitrile with good-to-excellent yields. 相似文献