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101.
We present a protocol for perfectly teleporting a five-qubit state of specific type. We utilize a sixqubit entangled quantum channel for this purpose. In this protocol only four out of 26 possible measurement outcomes appear. This leads to a substantial convenience in the implementation of the protocol.  相似文献   
102.
We develop a scheme to construct the Hamiltonians of the lambda-, vee- and cascade-type three-level configurations using the generators of SU(3) group. It turns out that this approach provides a well-defined selection rule to give different Hamiltonians for each configuration. The lambda- and vee-type configurations are exactly solved with different initial conditions while taking the two-mode classical and quantized fields. For the classical field, it is shown that the Rabi oscillation of the lambda model is similar to that of the vee model and the dynamics of the vee model can be recovered from lambda model and vice versa simply by inversion. We then proceed to solve the quantized version of both models by introducing a novel Euler matrix formalism. It is shown that this dynamical symmetry exhibited in the Rabi oscillation of two configurations for the semiclassical models is completely destroyed on quantization of the field modes. The symmetry can be restored within the quantized models when both field modes are in the coherent states with large average photon number which is depicted through the collapse and revival of the Rabi oscillations.   相似文献   
103.
Bishler  L.  Dhara  Saswati  Grigoryev  T.  Mironov  A.  Morozov  A.  Morozov  An.  Ramadevi  P.  Singh  Vivek Kumar  Sleptsov  A. 《JETP Letters》2020,111(9):494-499
JETP Letters - We evaluate the differences of HOMFLY-PT invariants for pairs of mutant knots colored with representations of SL(N), which are large enough to distinguish between them. These mutant...  相似文献   
104.
While a stable base-free arylalumylene bearing a sterically encumbered terphenyl substituent has been reported previously, we herein report that our attempts to form a base-stabilised arylalumylene bearing a relatively small terphenyl substituent and an N-heterocyclic carbene base led instead to a “masked” dialumene (LRAl Created by potrace 1.16, written by Peter Selinger 2001-2019 AlRL), self-stabilised by one peripheral aromatic group. Intriguingly, examining the behavior of this species or its transient dialumene formed from reducing the diiodoarylalane in aromatic solvents under different conditions reveals that they both decouple into the desired base-stabilised arylalumylene. This transient acyclic, dicoordinate alumylene is highly reactive, deconstructing benzene and toluene to furnish dialuminium derivatives of pentalene, providing the first example of a neutral AlI compound able to deconstruct these less reactive arenes. Computational insights were also gained on the dialumene dissociation and on the mechanism of arene deconstruction by alumylene.

Attempts to form a base-stabilised arylalumylene by reducing an NHC-coordinated diiodoterphenylalane led to a masked dialumene. Reactivity studies showed it decouples to initially aimed arylalumylene, which easily deconstructs less reactive arenes.  相似文献   
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108.
The Fabri-Picasso formulation of the spontancous breaking of theSU A (3) symmetry is applied to theU A (1) symmetry. It is argued that the notion of the spontaneous breaking of theU A (1) symmetry is different from that of theSU A (3) symmetry. In contrast to the octet sector, absence of the massless Goldstone mode amounts to the existence of an exotic vacuum-like degenerated state.  相似文献   
109.
The first azo-imine chelate system, Pd(N(H)C(R)NNPh)(2) (Pd(RA)(2)), has been isolated in the form of diamagnetic solids by the 6e(-)-6H(+) reduction of bis(phenylazooximato)palladium(II), Pd(N(O)C(R)NNPh)(2) (abbreviated Pd(RB)(2)), with ascorbic acid in a mixed solvent (R = Ph, alpha-naphthyl). Selected spectral features are described. The X-ray structures of Pd(PhA)(2) and Pd(PhB)(2) have revealed trans-planar geometry consistent with metal oxidation state of +2. Bond length trends within the chelate rings are rationalized in terms of steric and electronic factors. In Pd(PhA)(2) a total of 10 ligand pi electrons are present, each formally monoanionic ligand contributing five. Model EHMO studies have revealed that the filled HOMO (a(u)) in Pd(RA)(2) is a bonding combination of two ligand pi orbitals with large azo contributions. The LUMO (b(g)) is roughly the corresponding antibonding combination. The outer pi-electron configuration of Pd(RA)(2) is (a(u))(2)(b(g))(0). Four successive voltammetric responses, two oxidative and two reductive, are observed. The E(1/2) range is -1.3 to +0.8 V vs SCE for Pd(PhA)(2) in a 1:9 MeCN-CH(2)Cl(2) mixture (Pt electrode). EPR and electronic spectra of the electrogenerated one-electron-oxidized complex Pd(PhA)(2)(+) are described. The azo-imine system is compared with imine-imine and azo-azo systems. Crystal data for the complexes are as follows. Pd(PhA)(2): crystal system monoclinic; space group C2/c; a = 18.167(5) ?, b = 7.420(3) ?, c = 16.527(6) ?; beta = 92.70(3) degrees; V = 2225(1) ?(3); Z = 4; R = 2.61%, R(w) = 3.58%. Pd(PhB)(2): crystal system monoclinic; space group P2(1)/n; a = 5.735(5) ?, b = 10.797(6) ?, c = 18.022(11) ?; beta = 97.73(6) ?; V = 1105(1) ?(3); Z = 2; R = 3.37%; R(w) = 3.40%.  相似文献   
110.
Tetrameric [{RZn(NHNMe2)}4] (R = Me, Et), the first organometallic zinc hydrazides to be described, have been prepared by alkane elimination from dialkylzinc solutions and N,N-dimethylhydrazine. They were characterised by 1H and 13C NMR and IR spectroscopy, mass spectrometry, elemental analysis and X-ray crystallography. The compounds form asymmetric aggregates containing the novel Zn4N8 core; tetrahedra of Zn atoms bear the alkyl groups at Zn, with the triangular faces bridged by NHNMe2 substituents. The NH groups are connected to two Zn atoms, and the NMe2 groups to one. Hydrolysis of the compounds with water gives [(RZn)4(OH)(NHNMe2)3] as products, which also were characterised as described above. Higher yields of these hydroxo clusters were achieved in one-pot syntheses by reaction of dialkylzinc solutions with mixtures of N,N-dimethylhydrazine and water. They contain Zn4N6O cages, in which one hydroxide in the tetrameric hydrazides described above replaces one NHNMe2 group. Similar products can be prepared with alkoxy instead of hydroxy groups, in analogous one-pot syntheses with alcohols. Alcoholysis of [EtZn(NHNMe2)]4 with methanol or ethanol gave zinc trishydrazide monoalkoxides, [(EtZn)4(OR)(NHNMe2)3] (R = Me, Et), which have constitutions analogous to the monohydroxides. The organozinc bishydrazide bisalkoxides [(MeZn)4(NHNMe2)2(OEt)2] and [(EtZn)4(NHNMe2)2(OEt)2] were obtained in one-pot reactions from dialkylzinc solutions with mixtures of the hydrazine and alcohol, and their crystal structures, confirmed by spectroscopic methods in solution, show an unsymmetrical aggregation with the novel Zn4N4O2 cage structure.  相似文献   
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