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31.
An Unsharp Logic from Quantum Computation   总被引:1,自引:0,他引:1  
Logical gates studied in quantum computation suggest a natural logical abstraction that gives rise to a new form of unsharp quantum logic. We study the logical connectives corresponding to the following gates: the Toffoli gate, the NOT and the $\sqrt {NOT} $ (which admit of natural physical models). This leads to a semantic characterization of a logic that we call quantum computational logic (QCL).  相似文献   
32.
The notion of coexistence between questions is introduced in the framework of Piron's approach to quantum physics, using Aerts' notion of performable-together questions. Relationships between coexistence of questions and Piron's compatibility of propositions are investigated. In particular, properties generated by coexistent and primitive questions are compatible.  相似文献   
33.
The effect of pretreatments as well as of rhodium precursor and of the support over the morphology of Rh nanoparticles were investigated by Fourier transform infrared (FT-IR) spectroscopy of adsorbed CO. Over a Rh/alumina catalyst, both metallic Rh particles, characterized by IR bands in the range 2070-2060 cm-1 and 1820-1850 cm-1, and highly dispersed rhodium species, characterized by symmetric and asymmetric stretching bands of RhI(CO)2 gem-dicarbonyl species, are present. Their relative amount changes following pretreatments with gaseous mixtures, representative of the catalytic partial oxidation (CPO) reaction process. The Rh metal particle fraction decreases with respect to the Rh highly dispersed fraction in the order CO approximately CO/H2 > CH4/H2O, CH4/O2 > CH4 > H2. The metal particle dimensions decrease in the order CH4/O2 > H2 > CH4/H2O > CO > CO/H2. Grafting from a carbonyl rhodium complex also increases the amount and the dimensions of Rh0 particles at the catalyst surface. Increasing the ratio (extended rhodium metal particles/highly dispersed Rh species) allows a shorter conditioning process. The surface reconstruction phenomena going on during catalytic activity are related to this effect.  相似文献   
34.
Reaction of MX2 (M = Cd, Zn; X = Cl, Br, I) with 2-cyanopyrazine leads to the formation of compounds with the composition CdX2(2-cyanopyrazine)2 (X = Cl; CdCl , X = Br; CdBr and X = I; CdI ) and ZnX2(2-cyanopyrazine)2 (X = Cl; ZnCl , X = Br; ZnBr and X = I; ZnI/I ). In the crystal structures of the Cd compounds and in ZnCl , the metal cations are octahedrally coordinated and are linked into chains by the halide anions via common edges. In contrast, in the crystal structures of ZnBr and ZnI/I the metal cations are tetrahedrally coordinated into discrete complexes. Further investigations show that a second modification of ZnCl2(2-cyanopyrazine)2 exists ( ZnI/II ), which is formed by kinetic control. The thermal properties of the 2-cyanopyrazine rich compounds were investigated by TG-DTA and temperature dependent XRPD measurements. Upon heating the Cd compounds, all 2-cyanopyrazine ligands are removed in a single step with no indication of the formation of a 2-cyanopyrazine deficient phase. A similar behavior is observed for ZnI , whereas for ZnCl and ZnBr , TG-DTA measurements suggest the formation of a 2-cyanopyrazine deficient phase that, in case of ZnBr , cannot be isolated and, for ZnCl , cannot be obtained pure. The emission of these compounds is shifted from the blue to orange depending on the crystal structure and the nature of the halide anion.  相似文献   
35.
Reduction of Pd° and decomposition of palladium oxide supported on γ-alumina were studied at atmospheric pressure under different atmospheres (H(2), CH(4), He) over a 4 wt% Pd/Al(2)O(3) catalyst (mean palladium particle size: 5 nm with 50% of small particles of size below 5 nm). During temperature programmed tests (reduction, decomposition and oxidation) the crystal domain behaviour of the PdO/Pd° phase was evaluated by in situ Raman spectroscopy and in situ XRD analysis. Under H(2)/N(2), the reduction of small PdO particles (<5 nm) occurs at room temperature, whereas reduction of larger particles (>5 nm) starts at 100 °C and is achieved at 150 °C. Subsequent oxidation in O(2)/N(2) leads to reoxidation of small crystal domain at ambient temperature while oxidation of large particles starts at 300 °C. Under CH(4)/N(2), the small particle reduction occurs between 240 and 250 °C while large particle reduction is fast and occurs between 280 and 290 °C. Subsequent reoxidation of the catalyst reduced in CH(4)/N(2) shows that small and large particle oxidation of Pd° starts also at 300 °C. Under He, no small particle decomposition is observed probably due to strong interactions between particles and support whereas large particle reduction occurs between 700 and 750 °C. After thermal decomposition under He, the oxidation starts at 300 °C. Thus, the reduction phenomenon (small and large crystal domain) depends on the nature of the reducing agent (H(2), CH(4), He). However, whatever the reduction or decomposition treatment or the crystal domain, Pd° oxidation starts at 300 °C and is completed only at temperatures higher than 550 °C. Under lean conditions, with or without water, the palladium consists of reduced sites of palladium (Pd°, Pd(δ+) with δ < 2 or PdO(x) with x < 1) randomly distributed on palladium particles.  相似文献   
36.
We investigate the relativistic equation of state of hadronic matter and quark-gluon plasma at finite temperature and baryon density in the framework of the non-extensive statistical mechanics, characterized by power-law quantum distributions. We impose the Gibbs conditions on the global conservation of baryon number, electric charge and strangeness number. For the hadronic phase, we study an extended relativistic mean-field theoretical model with the inclusion of strange particles (hyperons and mesons). For the quark sector, we employ an extended MIT-Bag model. In this context we focus on the relevance of non-extensive effects in the presence of strange matter.  相似文献   
37.
Metal–organic frameworks (MOFs) are a class of porous materials that show promise in the removal of toxic industrial chemicals (TICs) from contaminated airstreams, though their development for this application has so far been hindered by issues of water stability and the wide availability and low cost of traditionally used activated carbons. Here a series of three MOF‐activated carbon composite materials with different MOF to carbon ratios are prepared by growing STAM‐17‐OEt crystals inside the commercially available BPL activated carbon. The composite materials display excellent water stability and increased uptake of ammonia gas when compared to unimpregnated carbon. Such properties make these composites very promising in the fields of air purification and personal protective equipment.  相似文献   
38.
39.
In recent years, a number of new designer drugs have entered the illicit drug market. The methylenedioxyderivatives of amphetamine represent the largest group of designer drugs. This paper describes a method for screening for and simultaneously quantifying 10 2,5-methylenedioxy-derivatives of amphetamine and phenethylamine in human whole blood, using capillary electrophoresis (CE) with diode array detection (DAD). Using an aqueous pH 2.5 phosphate buffer, CE analysis gave peaks with good symmetry and reproducible migration times. Under these experimental conditions, the 10 amphetamines were resolved in 15 min and without interference from biological matrices (blood). Their identification by migration time was confirmed by their UV spectra recorded with a DAD (190-350 nm). The main advantages of the present method lie in its simplicity, clean and reliable extraction from human whole blood and simultaneous detection and quantification by CE-DAD. The applicability of the method was demonstrated by analysis of in vivo rat blood samples. The method was validated according to international guidelines.  相似文献   
40.
The set E(S) of all splitting subspaces, i.e., of all subspaces M of an inner product space S for which MM =S holds, is an orthocomplemented orthomodular orthoposet and it has already been shown that the ordering property on E(S) of being a complete lattice characterizes the completeness of inner product spaces. In this work this last result is generalized proving that S is a Hilbert space under the weaker request that E(S) is a -lattice. As a marginal result, we also prove that an inner product space is complete if and only if the complete lattice (S) of all subspaces is orthomodular.  相似文献   
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