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71.
J. S. Amato V. J. Grenda T. M. H. Liu E. J. J. Grabowski 《Journal of heterocyclic chemistry》1979,16(6):1153-1155
Reactions of 2-(4′-fluorophenyl)imidazole ( 1 ) and related compounds under various nitrating conditions are discussed. With 90% nitric acid in 20% oleum at ?10°, 1 affords 2-(4′fluorophenyl)-4(5)-nitroimidazole ( 2 ) in 80% yield. Reaction of 2 with the same reagents at 25° affords 2-(4′-fluoro-3′-nitrophenyl)-4(5)-nitroimidazole ( 4 ) in 90% yield, whereas with 90% nitric acid in acetic acid at 95°, 2 affords 4,5-dinitro-2-(4′-fluorophenyl)imidazole ( 5 ) in 80% yield. Reaction of 1 with 70% nitric acid in concentrated sulfuric acid at 25° affords 2-(4′-fluorophenyl)-5-hyroximinoimidazolin-4-one ( 6 ), which rearranges and hydrolyzes to 5-(4′-fluorophenyl)-1,2,4-oxadiazole-3-carboxylic acid. A discussion of these reactions is presented. 相似文献
72.
73.
Ma?gorzata?Domaga?aEmail author Magdalena?Ma?ecka Katarzyna?Urbaniak Grzegorz?Mlostoń S?awomir?J.?Grabowski 《Structural chemistry》2005,16(1):55-59
The crystal structures of dimethyl 2,2,4,4-tetramethyl-3-oxocyclobutane-1-spiro-5-3,4-diphenyl-(1,3)-thiazolidine-2,2-dicarboxylate, C26H29NO5S for V, and dimethyl 3,4-diphenyl-5-isopropylidene-(1,3)-thiazolidine-2,2-dicarboxylate, C22H23NO4S for VI, have been solved. The 1,3-thiazolidine ring of compound V has got twisted conformation, while in compound VI this ring adopts envelope. In both structures short inter- and intramolecular contacts were found, which can be recognized as hydrogen bonds. 相似文献
74.
Preparation and Characterization of [Pt(mal)2]2? and trans-[Pt(mal)2X2]2? (X = Cl, Br, I, SCN) By twofold treatment of K2[PtCl4] with potassium hydrogen malonate in a queous solution the yellow K2[Pt(mal)2] · H2O is obtained. After extraction with tetrabutylammonium ions into dichloromethane by oxidative addition at ?90°C the PtIV complexes [Pt(mal)2X2]2?, X = Cl, Br, I, SCN, are formed. The SCN ligands are coordinated to Pt via S. The IR and Raman spectra are discussed and assigned. 相似文献
75.
L. R. Grabowski E. M. van Veldhuizen A. J. M. Pemen W. R. Rutgers 《Plasma Chemistry and Plasma Processing》2006,26(1):3-17
A small batch reactor is developed to study the removal of phenol from a thin layer of water by creating pulsed corona discharges
above the water. Pulses of up to 40 kV are applied with a duration of ~50 ns and an energy of ~60 mJ. In this CAW (Corona
Above Water) reactor an ozone yield of upto 90 g/kWh is obtained in ambient air. The phenol degradation is 48 g/kWh, using
a 1 mM initial concentration in demineralized water. The degradation yield increases to almost 100 g/kWh by adding to the
water either H2O2 or Fe2SO4 or NaOH. The first two additions are considered to increase to amount of OH radicals. In the case of NaOH addition it is
observed that much more ozone dissolves in the water. The addition of the OH scavenger t-butanol shows that in most cases
the main oxidation route of phenol in the CAW reactor is direct ozone attack. 相似文献
76.
77.
78.
Łukasz Grabowski 《Mathematische Annalen》2015,363(1-2):637-656
79.
C–H?N and C–H?S hydrogen bonds were analyzed in complexes where acetylene, ethylene, methane and their derivatives are proton donors while ammonia and hydrogen sulfide are proton acceptors. Ab initio calculations were performed to analyze those interactions; MP2 method was applied and the following basis sets were used: 6-311++G(d,p), aug-cc-pVDZ and aug-cc-pVTZ. The results showed that hydrogen bonds for complexes with ammonia are systematically stronger than such interactions in complexes with hydrogen sulfide. If the fluorine substituted hydrocarbons are considered then F-substituents enhance the strength of hydrogen bonding. For a few complexes, mainly those where carbon atom in proton donating C–H bond possesses sp3 hybridization, the blue-shifting hydrogen bonds were detected. Additionally, Quantum Theory of ‘Atoms in Molecules’ and Natural Bond Orbitals method were applied to analyze H-bond interactions. 相似文献
80.
Lipkowski P Grabowski SJ Leszczynski J 《The journal of physical chemistry. A》2006,110(34):10296-10302
X-Cl...H-Y interactions are analyzed by applying ab initio methods as well as the Bader theory. All calculations were performed using Pople's basis sets (6-311++G(2df,2pd) and 6-311++G(3df,3pd)) as well as the Dunning-type bases (aug-cc-pVDZ and aug-cc-pVTZ) within the MP2 method. For the complexes analyzed here, X-Cl and H-Y may be treated as a Lewis acid and a Lewis base, respectively. The Cl...H interactions are rather weak or at most moderate since, for the strongest interaction of the F3...HLi complex, the binding energy calculated at the MP2/6-311++G(3df,3pd) level of approximation amounts to -3.4 kcal/mol, and the H...Cl distance is equal to 2.65 A, less than the corresponding sum of van der Waals radii. These interactions may be classified as halogen-hydride interactions. However, some of the complexes analyzed, especially F3SiCl...HBeF and F3SiCl...HBeF, are very weakly bound, probably by typical van der Waals interactions. 相似文献