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981.
Alain-Claude Gillard Sylvain Rault Michel Boulouard Max Robba 《Journal of heterocyclic chemistry》1995,32(6):1741-1745
Reactivity of 1,2,3,10,11,11a-hexahydro-5H-thiazolo[4,3-c][1,4]benzodiazepin-5-one-11-thione and 1,2,3,10,11,11a-hexahydro-5H-thiazolo[4,3-c][1,4]benzodiazepine-5,11-dithione was evaluated against various amines. The synthetic pathways involved in these reactions which led to new thiazolo[4,3-c]-[1,4]benzodiazepine amidines are described. 相似文献
982.
Reaction of potassium aryltrifluoroborates with aldehydes, in the presence of a rhodium catalyst, afforded carbinol derivatives in high yields under mild aqueous conditions; this efficient reaction proved to be general, allowing the production of highly hindered diarylmethanols and aliphatic aldehydes were also reactive under these conditions. 相似文献
983.
Vladimir Carranza Tllez Brenda Snchez Gaytn Sylvain Berns Enrique Gonzlez Vergara 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o228-o230
The structure of pyridine‐2,6‐dicarboxylic acid, C7H5NO4, has been determined at 0.71 Å resolution. The molecule is located on a site with mirror symmetry. A one‐dimensional supramolecular structure is stabilized in the solid state through a strong symmetric double hydrogen bond, with H?O distances of 1.86 (3) Å and O—H?O angles of 167 (3) and 171 (5)°. This arrangement is similar but not identical to that reported for the isoelectronic isophthalic acid (benzene‐1,3‐dicarboxylic acid). 相似文献
984.
Based on our synthetic strategy developed for the total synthesis of the macrocyclic salicylate natural product salicylihalamide, we describe herein the synthesis of a series of simplified salicylihalamide-based analogs. Alterations in the aromatic fragment, the macrolactone scaffold and side-chain were evaluated for in vitro inhibition of V-ATPase activity and human tumor cell growth. 相似文献
985.
We report the practical synthesis of the new 5-azidopyrrolo[2,1-c][1,2,4]triazolo[4,3-a][1,4]benzo-diazepin-8-one and 11-alkylamino-2-azidopyrrolo[2,1-c][1,4]benzodiazepines via the corresponding hydroxy compounds. 相似文献
986.
A direct cross-coupling reaction of aromatic aldehydes with potassium trifluoro(organo)borates afforded ketones in high yields and under mild conditions in the presence of a rhodium catalyst and acetone. This new reaction, involving a formal aldehyde C-H bond activation, is believed to proceed via a Heck-type mechanism followed by hydride transfer to acetone. 相似文献
987.
Baudron SA Batail P Coulon C Clérac R Canadell E Laukhin V Melzi R Wzietek P Jérome D Auban-Senzier P Ravy S 《Journal of the American Chemical Society》2005,127(33):11785-11797
(EDT-TTF-CONH2)6[Re6Se8(CN)6], space group R, was prepared by electrocrystallization from the primary amide-functionalized ethylenedithiotetrathiafulvalene, EDT-TTF-CONH2 (E(1/2)1 = 0.49 V vs SCE in CH3CN), and the molecular cluster tetraanion, [Re6Se8(CN)6]4- (E(1/2) = 0.33 V vs SCE in CH3CN), equipped with hydrogen bond donor and hydrogen bond acceptor functionalities, respectively. Its Kagome topology is unprecedented for any TTF-based materials. The metallic state observed at room temperature has a strong two-dimensional character, in coherence with the Kagome lattice symmetry, and the presence of minute amounts of [Re6Se8(CN)6](3-)* identified by electron spin spectroscopy. A structural instability toward a distorted form of the Kagome topology of lesser symmetry is observed at ca. 180 K. The low-temperature structure is associated with a localized, electrically insulating electronic ground state and its magnetic susceptibility accounted for by a model of uniform chains of localized S = 1/2 spins in agreement with the 100 K triclinic crystal structure and band structure calculations. A sliding motion, within one out of the three (EDT-TTF-CONH2)2 dimers coupled to the [Re6Se8(CN6)(3-)*]/[Re6Se8(CN6)4-] proportion at any temperature, and the electronic ground state of the organic-inorganic hybrid material are analyzed on the basis of ESR, dc conductivity, 1H spin-lattice relaxation, and static susceptibility data which qualify a Mott localization in [EDT-TTF-CONH2]6[Re6Se8(CN)6]. The coupling between the metal-insulator transition and a structural transition allows for the lifting of a degeneracy due to the ternary axis in the high temperature, strongly correlated metallic phase which, in turn, leads to Heisenberg chains at low temperature. 相似文献
988.
Sylvain Rault Michel Cugnon De Svricourt Paulette Touzot Max Robba Hussein El-Kashef 《Journal of heterocyclic chemistry》1980,17(7):1399-1404
The nitration and bromination of both [1]benzothieno[3,2-d]pyrimidin-4(3H)one ( 1 ) and [1]benzothieno-[3,2-d]pyrimidine ( 2 ) has been studied. Nitration of 1 at ?30° afforded a mixture of 8-nitro[1]benzothieno-[3,2-d]pyrimidin-4(3H)one ( 7b ) (70%) and 6-nitro[1]benzothieno[3,2-d]pyrimidin-4(3H)one ( 7a ) (30%). However when the nitration was carried out at 60°, the 6,8-dinitro derivative 8 was the result. On the contrary, the nitration of 2 at ?30° gave a single nitration product, 8-nitro[1]benzothieno[3,2-d]pyrimidine ( 11 ). The bromination of both 1 and 2 gave the corresponding 8-bromo derivatives 10 and 13 . Assignment of structure of all the products was based on ir and nmr spectral studies and on unequivocal syntheses. 相似文献
989.
Xiao Feng Jean-Charles Lancelot Alain-Claude Gillard Henriette Landelle Sylvain Rault 《Journal of heterocyclic chemistry》1998,35(6):1313-1316
The synthetic pathway leading to 5,6-dihydro-4H-furo[3,2-f]pyrrolo[1,2-a][1,4]diazepines is described in four steps starting from α-bromophenones via 2-amino-3-furonitriles. 相似文献
990.
Yamien Effi Jean-Charles Lancelot Sylvain Rault Max Robba 《Journal of heterocyclic chemistry》1983,20(4):913-918
The 4,5-dihydropyrrolo[1,2-e]pyrazin-5-one (1) exhibits lactam-lactim tautomerism. N-Electrophilic substitutions could be achieved via the intermediate of the substitutions could be achieved via the intermediate of the sodium salt la. The 5-chloropyrazine 11 obtained by chlorodehydroxylation of pyrazinone 1 allowed nucleophilic substitution. Thionation of the pyrazinone 1 afforded the thioxopyrazine 27 wich gave studied and the tautomerism of the hydrazinopyrazine 14 and its derivatives are discussed in terms of hydrazone and azine structures 相似文献