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81.
Ultrabroadband infrared solid-state lasers   总被引:1,自引:0,他引:1  
Ultrabroadband infrared transition metal ion-doped solid-state lasers have come of age and are increasingly being used in trace gas monitoring, remote sensing, telecommunications, ophthalmology, and neurosurgery. Operating at room temperature, they are stable, versatile, and easy to handle successors to the color center lasers. They are becoming the critical components in optical frequency standards, space-based remote sensing systems, and may soon find application in femtochemistry and attosecond science. The article reviews the principles and basic physics of these types of lasers, which are distinguished by their ability to support the shortest pulses down to single optical cycle durations and the ultimately broad tuning ranges. The paper further reviews the state of the art in the existing diode-pumped sources of broadly tunable continuous wave, and ultrashort pulsed radiation in the infrared, and provides examples of their successful application to supercontinuum generation, trace gas measurements, and ultrasensitive intracavity spectroscopy. Developments in such lasers as Cr:YAG, Cr:ZnSe, Cr:ZnS, as well as the recently proposed mixed Cr:ZnS/sub x/Se/sub 1-x/ laser, are discussed in more detail. These lasers nearly continuously cover the infrared spectral region between 1.3 and 3.1 /spl mu/m. The gain spectra of these lasers perfectly match and extend toward the infrared spectra of such established ultrabroadband lasers, operating at shorter wavelengths between /spl sim/0.7-1.3 /spl mu/m, as Ti:sapphire, Cr:LiSAF/Cr:LiSGaF and Cr:forsterite. This opens up new opportunities for synthesis of single-cycle optical pulses and frequency combs in the infrared.  相似文献   
82.
In parameterized string matching the pattern P matches a substring t of the text T if there exist a bijective mapping from the symbols of P to the symbols of t. We give simple and practical algorithms for finding all such pattern occurrences in sublinear time on average. The algorithms work for a single and multiple patterns.  相似文献   
83.
84.
Fibroblast growth factor receptor (FGFR) activation leads to receptor autophosphorylation and increased tyrosine phosphorylation of several intra cellular proteins. We have previously shown that autophosphorylated tyrosine 766 in FGFR1 serves as a binding site for one of the SH2 domains of phospholipase Cy and couples FGFR1 to phosphatidylinositol hydrolysis in several cell types. In this report, we describe the identification of six additional autophosphorylation sites (Y-463, Y-583, Y-585, Y-653, Y-654 and Y-730) on FGFR1. We demonstrate that autophosphorylation on tyrosines 653 and 654 is important for activation of tyrosine kinase activity of FGFR1 and is therefore essential for FGFR1-mediated biological responses. In contrast, autophosphorylation of the remaining four tyrosines is dispensable for FGFR1-mediated mitogen-activated protein kinase activation and mitogenic signaling in L-6 cells as well as neuronal differentiation of PC12 cells. Interestingly, both the wild-type and a mutant FGFR1 (FGFR1-4F) are able to phosphorylate Shc and an unidentified Grb2-associated phosphoprotein of 90 kDa (pp90). Binding of the Grb2/Sos complex to phosphorylated Shc and pp90 may therefore be the key link between FGFR1 and the Ras signaling pathway, mito-genesis, and neuronal differentiation.  相似文献   
85.
86.
87.
Natural organic matter (NOM) isolated from the eutrophic Sanctuary Pond (Point Pelee National Park, Canada) has an adverse impact on amphipod species (Gammarus tigrinus and Chaetogammarus ischnus from Lake Müggelsee, Germany, and Eulimnogammarus cyaneus, from Lake Baikal, Russia). Increases in amphipod mortality, changes in peroxidase activity and increases of heat shock protein (hsp70) expression were observed upon exposure to NOM. The highest resistance to the adverse impact of NOM was observed with the endemic Baikalian amphipod E. cyaneus. However, the mechanisms behind this finding remains obscure. If differences in the sensitivity of the hsp70 antibody may be excluded, different modes of action may be postulated: because the adverse impact of NOM may be caused by reactive oxygen species (ROS) and the NOM itself, the observed differences may be due to the action of ROS alone (with E. cyaneus) and a combination of both adverse modes of action (European species).  相似文献   
88.
The DVR3D program suite calculates energy levels, wavefunctions, and where appropriate dipole transition moments, for rotating and vibrating triatomic molecules. Potential energy and, where necessary, dipole surfaces must be provided. Expectation values of geometrically defined functions can be calculated, a feature which is particularly useful for fitting potential energy surfaces. The programs use an exact (within the Born-Oppenheimer approximation) Hamiltonian and offer a choice of Jacobi or Radau internal coordinates and several body-fixed axes. Rotationally excited states are treated using an efficient two-step algorithm. The programs uses a Discrete Variable Representation (DVR) based on Gauss-Jacobi and Gauss-Laguerre quadrature for all 3 internal coordinates and thus yields a fully point-wise representation of the wavefunctions. The vibrational step uses successive diagonalisation and truncation which is implemented for a number of possible coordinate orderings. The rotational, expectation value and transition dipole programs exploit the savings offered by performing integrals on a DVR grid. The new version has been rewritten in FORTRAN 90 to exploit the dynamic array allocations and the algorithm for dipole and spectra calculations have been substantially improved. New modules allow the z-axis to be embedded perpendicular to the plane of the molecule and for the calculation of expectation values.

Program summary

Title of the program: DVR3D suiteCatalogue number: ADTIProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTIProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandProgramming language: Fortran 90No. of lines in distributed program, including test data, etc.: 61 574No. of bytes in distributed program, including test data, etc.: 972 404Distribution format: tar.gz

New version summary

Title of program: DVR3DRJZCatalogue number: ADTBProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTBProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandReference in CPC to previous version: 86 (1995) 175Catalogue identifier of previous version: ADAKAuthors of previous version: J. Tennyson, J.R. Henderson and N.G. FultonDoes the new version supersede the original program?: DVR3DRJZ supersedes DVR3DRJComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 Unix; SGI Origin 2000, Sunfire V750 and V880 systems running SunOS, IBM p690 Regatta running AIXProgramming language used in the new version: Fortran 90Memory required to execute: case dependentNo. of lines in distributed program, including test data, etc.: 4203No. of bytes in distributed program, including test data, etc.: 30 087Has code been vectorised or parallelised?: The code has been extensively vectorised. A parallel version of the code, PDVR3D has been developed [1], contact the first author for detailsAdditional keywords: perpendicular embeddingDistribution format: gzNature of physical problem: DVR3DRJZ calculates the bound vibrational or Coriolis decoupled rotational-vibrational states of a triatomic system in body-fixed Jacobi (scattering) or Radau coordinates [2]Method of solution: All coordinates are treated in a discrete variable representation (DVR). The angular coordinate uses a DVR based on (associated) Legendre polynomials and the radial coordinates utilise a DVR based on either Morse oscillator-like or spherical oscillator functions. Intermediate diagonalisation and truncation is performed on the hierarchical expression of the Hamiltonian operator to yield the final secular problem. DVR3DRJ provides the vibrational wavefunctions necessary for ROTLEV3, ROLEV3B or ROTLEV3Z to calculate rotationally excited states, DIPOLE3 to calculate rotational-vibrational transition strengths and XPECT3 to compute expectation valuesRestrictions on the complexity of the problem: (1) The size of the final Hamiltonian matrix that can practically be diagonalised. (2) The order of integration in the radial coordinates that can be dealt with within the machine exponent range. Some adjustment in the code may be necessary when large order Gauss-Laguerre quadrature is usedTypical running time: Case dependent but usually dominated by the final (3D) matrix diagonalisation. The test runs take minutes on a fast PCUnusual features of the program: A user supplied subroutine containing the potential energy as an analytic function is a program requirementReferences:
[1]
H.Y. Mussa, J. Tennyson, Comput. Phys. Commun. 128 (2000) 434.
[2]
J. Tennyson, B.T. Sutcliffe, Internat. J. Quantum Chem. 42 (1992) 941.

New version summary

Title of program: ROTLEV3Catalogue number: ADTCProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTCProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandReference in CPC to previous version: 86 (1995) 175Catalogue identifier of previous version: ADALAuthors of previous version: J. Tennyson, J.R. Henderson and N.G. FultonDoes the new version supersede the original program?: YesComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 Unix; SGI Origin 2000, Sunfire V750 and V880 systems running SunOSProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 1514No. of bytes in distributed program, including test data, etc.: 12 652Has code been vectorised or parallelised?: The code has been extensively vectorised. A parallel version of the code, PROTLEV3 has been developed [1], contact the first author for detailsDistribution format: gzNature of physical problem: ROTLEV3 performs the second step in a two-step variational calculation for the bound rotational-vibrational levels of a triatomic system represented in either Jacobi or unsymmetrised Radau coordinatesMethod of solution: A basis is constructed from the solutions of the Coriolis decoupled problem provided by DVR3DRJZ. The angular coordinate is transformed back to a basis set representation. The sparse Hamiltonian matrix can be diagonalised iteratively or in coreRestrictions on the complexity of the problem: The size of matrix that can practically be diagonalisedTypical running time: Case dependent. The sample data takes less than a minute on a fast PCUnusual features of the program: Most data is read directly from DVR3DRJZ. ROTLEV3 can provide data to drive DIPOLE3 and/or XPECT3References: [1] H.Y. Mussa, J. Tennyson, Comput. Phys. Commun. 128 (2000) 434.

New version summary

Title of program: ROTLEV3BCatalogue number: ADTDProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTDProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandReference in CPC to previous version: 86 (1995) 175Catalogue identifier of previous version: ADAMAuthors of previous version: J. Tennyson, J.R. Henderson and N.G. FultonDoes the new version supersede the original program?: YesComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 Unix, Sunfire V750 and V880 systems running SunOSProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 2215No. of bytes in distributed program, including test data, etc.: 16 595Has code been vectorised or parallelised?: The code has been extensively vectorised. A parallel version of the code, PROTLEV3B has been developed [1], contact the first author for detailsDistribution format: gzNature of physical problem: ROTLEV3B performs the second step in a two-step variational calculation for the bound rotational-vibrational levels of a triatomic system represented by symmetrised Radau coordinates using a bisector embedding [2]Method of solution: A basis is constructed from the solutions of the Coriolis decoupled problem provided by DVR3DRJZ. The problem is constructed entirely within the DVR. The Hamiltonian matrix can be diagonalised iteratively or in coreRestrictions on the complexity of the problem: The size of matrix that can practically be diagonalisedTypical running time: Case dependent. The sample data takes a few minutes on a fast PCUnusual features of the program: Most data is read directly from DVR3DRJZ. ROTLEV3B can provide data to drive DIPOLE3 and/or XPECT3References:
[1]
H.Y. Mussa, J. Tennyson, Comput. Phys. Commun. 128 (2000) 434.
[2]
J. Tennyson, B.T. Sutcliffe, Internat. J. Quantum Chem. 42 (1992) 941.

Program summary

Title of program: ROTLEV3ZCatalogue number: ADTEProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTEProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 Unix, Sunfire V750 and V880 systems running SunOSProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 2919No. of bytes in distributed program, including test data, etc.: 17 241Keywords: rotationally excited state, Coriolis coupling, secondary variational method, sparse matrix, vectorised, perpendicular embedding, Radau coordinatesHas code been vectorised or parallelised?: The code has been extensively vectorisedDistribution format: gzNature of physical problem: ROTLEV3Z performs the second step in a two-step variational calculation for the bound rotational-vibrational levels of a triatomic system represented by symmetrised Radau coordinates using a perpendicular embedding [1]Method of solution: A basis is constructed from the solutions of the Coriolis decoupled problem provided by DVR3DRJZ. The problem is constructed entirely within the DVR. The Hamiltonian matrix is diagonalised in coreRestrictions on the complexity of the problem: The size of matrix that can practically be diagonalisedTypical running time: Case dependent. The sample data takes a few minutes on a fast PCUnusual features of the program: Most data is read directly from DVR3DRJZReferences: [1] M.A. Kostin, O.L. Polyansky, J.Tennyson, J. Chem. Phys. 116 (2002) 7564.

New version summary

Title of program: DIPOLE3Catalogue number: ADTFProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTFProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandReference in CPC to previous version: 86 (1995) 175Catalogue identifier of previous version: ADANAuthors of previous version: J. Tennyson, J.R. Henderson and N.G. FultonDoes the new version supersede the original program?: YesComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 Unix; SGI Origin 2000; sunfire V750 and V880 systemsProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 1921No. of bytes in distributed program, including test data, etc.: 15 685Has code been vectorised or parallelised?: The code has been extensively vectorised. Commands to parallelise the code using OpenMP are included in the sourceDistribution format: gzNature of physical problem: DIPOLE3 calculates dipole transition intensities between previously calculated wavefunction for both rotational and rotational-vibrational transitionsMethod of solution: Integrals over dipole surfaces are constructed using a DVR in all three coordinates, this requires a transformation of the angular wavefunctions. Wavefunctions generated by DVR3DRJZ and ROTLEV3 or ROTLEV3B are then used to give transition intensities for individual pairs of statesRestrictions on the complexity of the problem: The complexity of the problem that can be solved by DVR3DRJZ, ROTLEV3 or ROTLEV3BTypical running time: Case dependent. The test data takes a few seconds on a fast PCUnusual features of the program: Most data is read directly from DVR3DRJZ and ROTLEV3 or ROTLEV3B. DIPOLE provides data to drive SPECTRA

New version summary

Title of program: SPECTRACatalogue number: ADTGProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTGProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 UnixReference in CPC to previous version: 75 (1993) 339Catalogue identifier of previous version: ACNBAuthors of previous version: J. Tennyson, S. Miller and C.R. Le SueurDoes the new version supersede the original program?: YesProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 1037No. of bytes in distributed program, including test data, etc.: 9159Has code been vectorised or parallelised?: As execution times are very short this is usually not importantDistribution format: gzNature of physical problem: SPECTRA generates synthetic, frequency ordered spectra as a function of temperature. Absolute intensities can be calculated if the necessary data to calculate the partition function is suppliedMethod of solution: Transitions are sorted by frequency and weighted using Boltzmann statisticsRestrictions on the complexity of the problem: The complexity of problem that can be solved by other programs in the suiteTypical running time: Case dependent, but very small for sample dataUnusual features of the program: Most data is read directly from DIPOLE3. Some data from DVR3DRJZ and ROTLEV3 or ROTLEV3B may also be required

Program summary

Title of program: XPECT3Catalogue number: ADTHProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADTHProgram obtainable from: CPC Program Library, Queen's University of Belfast, N. IrelandComputer: PC running LinuxInstallation: desktopOther machines on which program tested: Compaq running True64 UnixProgramming language used: Fortran 90High speed storage required: case dependentNo. of lines in distributed program, including test data, etc.: 1214No. of bytes in distributed program, including test data, etc.: 9361Distribution format: gzKeywords: Expectation values, Hellmann-Feynman theorem, potential fittingHas code been vectorised or parallelised?: The code has been extensively vectorisedNature of physical problem: XPECT3 calculates expectation of geometrically defined operators using previously calculated wavefunctionsMethod of solution: Integrals over the user defined surfaces are constructed using a DVR in all three coordinates. Wavefunctions generated by DVR3DRJZ and ROTLEV3 or ROTLEV3B are then used to give expectation values for each stateRestrictions on the complexity of the problem: The complexity of problem that can be solved by DVR3DRJZ, ROTLEV3 or ROTLEV3BTypical running time: Case dependent. The test data takes a few seconds on a fast PCUnusual features of the program: Most data is read directly from DVR3DRJZ and ROTLEV3 or ROTLEV3B.  相似文献   
89.
90.
The status of the design work on an electrostatic tandem-accelerator with vacuum insulation for 2.5 MeV protons and up to 40 mA constant current is reported. This machine is to be used for solving problems of neutron therapy and the detection of explosives by nuclear-resonance absorption of -rays.  相似文献   
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