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101.
102.
We report experimental realization of a quasiparticle interferometer where the entire system is in 1/3 primary fractional quantum Hall state. The interferometer consists of chiral edge channels coupled by quantum-coherent tunneling in two constrictions, thus enclosing an Aharonov-Bohm area. We observe magnetic flux and charge periods h/e and e/3, equivalent to the creation of one quasielectron in the island. Quantum theory predicts a 3h/e flux period for charge e/3, integer statistics particles. Thus, the observed periods demonstrate the anyonic braiding statistics of Laughlin quasiparticles. 相似文献
103.
Bartolomé C Ramiro Z Pérez-Galán P Bour C Raducan M Echavarren AM Espinet P 《Inorganic chemistry》2008,47(23):11391-11397
Complexes [AuCl{C(NHR)(NHPy-2)}] (Py-2 ) 2-pyridyl; R ) Me, tBu, nBu, iPr, nheptyl) have been prepared in amodular way from [AuCl(CNPy-2)]. The carbene moiety has a hydrogen-bond supported heterocyclic structure similar to the nitrogen heterocyclic carbenes in the solid state, and in CH2Cl2 or acetone solution, which is open in the presence of MeOH. The compounds are good catalysts for the skeletal rearrangement of enynes, and for the methoxycyclization of enynes. In contrast, the complexes [AuCl{C(NHR)(NHPy-4)}] are scarcely active due to the blocking effect of the coordination position required for the catalysis by the nitrogen of the NHPy-4 group. 相似文献
104.
Sergei V. Levchik Giovanni Camino Maria Paola Luda Luigi Costa George Muller Bruno Costes Yves Henry 《先进技术聚合物》1996,7(11):823-830
The kinetics of curing tetraglycidyl 4,4′-diaminodiphenyl methane (TGDDM) or of the mixture TGDDM/diglycidylether of bisphenol A (DGEBA) by bis(m-aminophenyl)methylphosphine oxide (BAMPO) was studied using differential scanning calorimetry. At low advancement of curing (<50%), the low activation energy interaction between epoxy and amino groups seems to be controlled by diffusion, whereas above 50% the role of homopolymerization tends to increase and the process becomes chemically controlled. BAMPO shows a higher fire-retardant effectiveness in the mixture TGDDM/DGEBA than in TGDDM or DGEBA alone, for which the oxygen and nitrous oxide index tests suggest a condensed phase or a gas phase fire-retardant action depending on phosphorus content. An intumescent char is formed on the surface of burning fire-retarded specimens which tends, however, to be oxidized, thus reducing the fire-proofing effect at high BAMPO content. 相似文献
105.
Jorge García-Glez Zakariae Amghouz Sergei A. Khainakov Aránzazu Espina Belén F. Alfonso Camino Trobajo 《Journal of Thermal Analysis and Calorimetry》2014,118(2):783-791
The monoammonium salt of γ-titanium phosphate has been prepared by hydrothermal treatment of π-Ti2O(PO4)2·2H2O in the presence of urea and phosphoric acid, and its crystal structure was obtained by Rietveld analysis using powder X-ray diffraction data. γ-Ti(PO4)(NH4HPO4) crystallizes in the monoclinic space group P21/m with a = 5.0725(3) Å, b = 6.3101(3) Å, c = 11.2435(5) Å, β = 97.980(3)° (Z = 2). The structure consists of 2D titanium phosphate layers in the ab-plane. The titanium atoms and one of the phosphate groups are located nearly in the ab-plane of the layer. All the oxygen atoms of this phosphate group are involved in titanium coordination sphere. The other phosphate group located in the layers edges links two neighboring titanium atoms in the a-direction through two of its oxygen atoms. The remaining two oxygens are pointed toward the interlayer space being involved in hydrogen bond interactions with the ammonium ions. Each ammonium ion is shared by four oxygens belonging to four different phosphate hydroxyl groups. γ-Ti(PO4)(NH4HPO4) is stable until 453 K, while above this temperature, it transforms to γ’-Ti(PO4)(NH4HPO4) high temperature polymorph stable until 573 K. Thermal decomposition of this material leads to cubic TiP2O7 structure, with previous formation of two intermediate pseudo-layered compounds: Ti(PO4)(NH4HP2O7)0.5 and Ti(PO4)(H2P2O7)0.5. The activation energy of thermal decomposition has been calculated as a function of the extent of conversion applying the Kissinger–Akahira–Sunose (KAS) isoconversional method to the thermogravimetric data. 相似文献
106.
Jorge García-Glez Belén F. Alfonso José A. Huidobro Sergei A. Khainakov Germán R. Castro Camino Trobajo 《Journal of Thermal Analysis and Calorimetry》2014,118(2):759-765
Polycrystalline thorium(IV) phosphate-triphosphate, Th2(PO4)(P3O10) (1), was obtained by (NH4)2Th(PO4)2·H2O (2) heating from room temperature to 1,273 K. 1 crystallizes in the orthorhombic space group Pn21 a (a = 11.6846(2) Å, b = 7.1746(1) Å, c = 12.9320(3) Å, Z = 4). Combining powder synchrotron X-ray diffraction data and DFT geometry optimization, a structural model is proposed for 1. The structure is built on ThO8 polyhedral chains along the b-axis. PO4 3? and P3O10 5? groups coexist in the structure and the latter group forms non-linear chains. Cohesion of the structure is made by the linkage of ThO8 chains by PO4 and P3O10 groups. Thermal transformation from 2 to 1 was monitored by thermogravimetric analysis (activation energy as a function of the extent of conversion was obtained from Kissinger–Akahira–Sunose (KAS) isoconversional method) and powder X-ray thermo-diffraction. For 2, the dehydration process takes place in two steps, with the apparition of a layered intermediate phase, (NH4)2Th(PO4)2·nH2O (0 < n < 1, d = 6.42 Å), previously to the formation of (NH4)2Th(PO4)2 (d = 6.31 Å). The condensation process produces an amorphous material that crystallizes to α-ThP2O7 (3) when the temperature increases. At 1,273 K, 3 slowly transforms to 1. 相似文献
107.
Aurore Vannier Sophie Duquesne Serge Bourbigot Jenny Alongi Giovanni Camino Ren Delobel 《Thermochimica Acta》2009,495(1-2):155-166
The incorporation of both OMPOSS and Exolit OP950 (zinc phosphinate) into PET leads to increased fire retarding properties and a synergistic effect has been established between the three components. Here the thermal degradation of OMPOSS, Exolit OP950, PET and blends of them is investigated via thermal degradation in pyrolytic and thermo-oxidative conditions. All species formed during the degradation of the additives or the blends are identified by solid state NMR and X-ray diffraction in the condensed phase and by GC–MS in the gas phase. The investigation shows that no chemical interaction occurs between the additives, which suggests that the synergy responsible for the improvement of fire properties of the material has a physical origin. 相似文献
108.
Bartolomé C Carrasco-Rando M Coco S Cordovilla C Espinet P Martín-Alvarez JM 《Dalton transactions (Cambridge, England : 2003)》2007,(45):5339-5345
Monomeric gold(I) carbenes of the type [AuR[C(NR1R2)(NHPy-4)]] (Py-4 = 4-pyridyl) have been prepared with R = C6F5, Fmes (2,4,6-tris(trifluoromethyl)phenyl) by reaction of the corresponding isocyanide compounds [AuR(CNPy-4)] with primary or secondary amines. The single crystal X-ray diffraction structures of [Au(C6F5)[C(NEt2)(NHPy-4)]].OH2, [Au(Fmes)[C(NEt2)(NHPy-4)]], and [Au(Fmes)[C(NHMe)(NHPy-4)]] show that the presence of the NHPy-4 moiety formed induces the formation of supramolecular macrocycles only supported by hydrogen bond interactions, either with N-H groups of other molecules (tetrameric macrocycles), or with water molecules (dimeric macrocycles). Dimeric gold(I) carbenes were also produced using a diamine to form a bridging carbene, or using octafluorobiphenyl to form a Au-C6F4-C6F4-Au bridge, but the solid state structures of these dimers could not be solved. Most of the complexes herein described display luminescent properties. 相似文献
109.
We address the problem of the connection among the geometric properties of quasi-Banach spaces linked to the notion of p-drop, such as p-Drop Property, Property p-(β), and uniform p-convexity. We completely settle the open question of whether they are mutually equivalent and put forward further research
topics to continue to explore the mysterious subject of the geometry of p<1. 相似文献
110.
A graph is superconnected, for short super-κ, if all minimum vertex-cuts consist of the vertices adjacent with one vertex. In this paper we prove for any r-regular graph of diameter D and odd girth g that if D≤g−2, then the graph is super-κ when g≥5 and a complete graph otherwise. 相似文献