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1.
Pietro Baraldi Gian Carlo Franchini Andrea Marchetti Gavino Sanna Lorenzo Tassi Alessandro Ulrici Giulia Vaccari 《Journal of solution chemistry》2000,29(5):489-504
Thermodynamic interactions in the ethane-1,2-diol (1) + 1,2-dimethoxyethane(2) + water (3) ternary system have been investigated in terms of the excessmolar volume, derived from density measurements at 19 different temperaturesfrom –10;dg to 80;dgC. Fourteen three-component mixtures have been considered,covering the entire composition range. The excess molar volumes are discussedin terms of conformational changes induced in each component by the presenceof another one. The results obtained support the hypothesis of the absence of anythree-component complex adducts under all experimental conditions investigated. 相似文献
2.
Daniele Simoni Giuseppe GianniniPier Giovanni Baraldi Romeo RomagnoliMarinella Roberti Riccardo RondaninRiccardo Baruchello Giuseppina GrisoliaMarcello Rossi Danilo MirizziFrancesco Paolo Invidiata Stefania GrimaudoManlio Tolomeo 《Tetrahedron letters》2003,44(14):3005-3008
A double Suzuki cross-coupling protocol has been devised as a practical route to a variety of terphenyls. Good chemoselectivity was observed. Unsymmetrically substituted triphenylenes were also easily prepared. 相似文献
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Pier Giovanni Baraldi Francesca Fruttarolo Mojgan Aghazadeh Tabrizi Romeo Romagnoli Delia Preti Ennio Ongini Hussein El‐Kashef María Dora Carrión Pier Andrea Borea 《Journal of heterocyclic chemistry》2007,44(2):355-361
The reaction between 3‐(dimethylamino)/3,3‐bis(methylthio)‐1‐(substituted)prop‐2‐en‐1‐ones and 4‐substituted‐5‐amino‐1H‐pyrazoles afforded new pyrazole[1,5‐a]pyrimidines structurally related to Zaleplon. The chemical modifications introduced at the 3‐, 5‐, and 7‐positions of the bicyclic structure revealed new promising candidates for the treatment of sleep disorders. 相似文献
6.
L. Gregoratti A. Baraldi V. R. Dhanak G. Comelli M. Kiskinova R. Rosei 《Surface science》1995,340(3):205-214
The effect of adsorbate coverage, adsorption sequence and temperature on the structure, composition and reactivity of coadsorbed layers, produced by dissociative adsorption of O2 and H2 at 200 K on a Rh(100) surface, has been studied by combined TPD, XPS and LEED measurements. The emphasis is on the impact of the structure and composition of the mixed O + H layers on the synthesis of hydroxyl and water as a result of the O + H surface reaction. The difference in the O 1s binding energies of adsorbed O (529.9 eV) and OH species (530.8 eV) was used as a fingerprint to monitor the formation of the OH species. The H2O TPD spectra show substantial variations of the desorption temperature range and the amount of water evolved with coadsorbate coverage and structure: from 270 to 350 K and from 0 to 0.08 ML, respectively. It has been found that dense O + H adlayers, where the O coverage is in the range 0.25-0.4 ML, favor the formation of stable OH species. The maximum amount of stable hydroxyl OH species ( 0.16 ML) can be produced by heating of these dense adlayers to 260 K. This results in reordering of the adspecies to form a new O + OH − (2 × 6) structure, where hydroxyls react readily to evolve 0.08 ML of water in a sharp desorption peak at 280 K. The effect of the adlayer density and restructuring on the production of OH and H2O is discussed. 相似文献
7.
The title compound C4H8N8S2HgBr2 was prepared and characterized by means of X-ray crystallography, and i.r. measurements. The crystals are orthorhombic, space group Pbcn (no. 60) witha=9.707(2),b=8.609(1),c=16.128(2) Å, andZ=4. The compound exhibits discrete monometallic units with the 1,2,4-triazole molecule acting as a monodentate ligand. The structure consists of units in which the mercury atom is coordinated in a distorted tetrahedral geometry by two sulfur and two bromine atoms. The NH and NH2 group of the 3-amino-5-mercapto-1,2,4-triazole unit are involved in intermolecular hydrogen bonds. Infrared bands are diagnostic of the coordination environment around the metal atoms. 相似文献
8.
The order–disorder phase transition on the α-Ga(0 1 0) structure was studied by spot-profile analysis low energy electron diffraction (SPA-LEED). A low temperature diffraction pattern reveals a small splitting of the overlayer spots which corresponds to a real-space distance of 81 Å, equivalent to 18 unit cells. The splitting is interpreted as caused by a regular ordering of anti-phase domains of the low-temperature phase. Due to the low symmetry of the surface, the domain boundaries are aligned only in one direction, giving rise to a regular, one-dimensional grid. The temperature dependence of the intensity and width of the reconstruction-induced diffraction spots is also investigated. It suggests that the phase transition takes place at a critical temperature Tc=232 K and that anti-phase boundary proliferation plays a role. 相似文献
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Miniussi E Pozzo M Baraldi A Vesselli E Zhan RR Comelli G Menteş TO Niño MA Locatelli A Lizzit S Alfè D 《Physical review letters》2011,106(21):216101
We report on a novel approach to determine the relationship between the corrugation and the thermal stability of epitaxial graphene grown on a strongly interacting substrate. According to our density functional theory calculations, the C single layer grown on Re(0001) is strongly corrugated, with a buckling of 1.6 ?, yielding a simulated C 1s core level spectrum which is in excellent agreement with the experimental one. We found that corrugation is closely knit with the thermal stability of the C network: C-C bond breaking is favored in the strongly buckled regions of the moiré cell, though it requires the presence of diffusing graphene layer vacancies. 相似文献