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81.
Hyun Jong Park Olga Kryliouk Tim Anderson Dmitry Khokhlov Timur Burbaev 《Physica E: Low-dimensional Systems and Nanostructures》2007,37(1-2):142
InN films and nanorods were grown by hydride metalorganic vapor phase epitaxy (H-MOVPE) and the effects of growth temperature, and NH3/TMIn and HCl/TMIn ratios on morphological dependences were studied. The growth habit of InN varied from thin film to microrod to nanorod to no deposition as the growth conditions were changed about transition from growth to etching conditions. The growth and etch regimes were also predicted by chemical equilibrium calculations of In–C–H–Cl–N-inert system. The optical properties of InN nanorods and columnar structured films were measured by room temperature PL and a maximum intensity was observed at 1.08 eV for both structures. 相似文献
82.
Jing Wang Christof Asbach Heinz Fissan Tim Hülser Thomas A. J. Kuhlbusch Drew Thompson David Y. H. Pui 《Journal of nanoparticle research》2011,13(4):1373-1387
Nanotechnology has great potential to transform science and industry in the fields of energy, material, environment, and medicine.
At the same time, more concerns are being raised about the occupational health and safety of nanomaterials in the workplace
and the implications of nanotechnology on the environment and living systems. Studies on environmental, health, and safety
(EHS) issues of nanomaterials have a strong influence on public acceptance of nanotechnology and, eventually, affect its sustainability.
Oversight and regulation by government agencies and non-governmental organizations (NGOs) play significant roles in ensuring
responsible and environmentally friendly development of nanotechnology. The EHS studies of nanomaterials can provide data
and information to help the development of regulations and guidelines. We present research results on three aspects of EHS
studies: physico-chemical characterization and measurement of nanomaterials; emission, exposure, and toxicity of nanomaterials;
and control and abatement of nanomaterial releases using filtration technology. Measurement of nanoparticle agglomerates using
a newly developed instrument, the Universal NanoParticle Analyzer (UNPA), is discussed. Exposure measurement results for silicon
nanoparticles in a pilot scale production plant are presented, as well as exposure measurement and toxicity study of carbon
nanotubes (CNTs). Filtration studies of nanoparticle agglomerates are also presented as an example of emission control methods. 相似文献
83.
J. F. Sharpey-Schafer T. E. Madiba S. P. Bvumbi E. A. Lawrie J. J. Lawrie A. Minkova S. M. Mullins P. Papka D. G. Roux J. Timár 《The European Physical Journal A - Hadrons and Nuclei》2011,47(1):6
The concept that the first excited 0+ states in N = 90 nuclei are not a b \beta -vibration but a second vacuum formed by the combination of the quadrupole pairing force and the low density of oblate orbitals
near the Fermi surface is supported by the blocking of this collective mode in 154Gd from coupling to the [505]11/2- single-particle quasi-neutron orbital in 155Gd . The coupling of this orbital to the 2+
g \gamma -vibration in 154Gd is observed since this coupling is not Pauli-blocked. 相似文献
84.
Durković M Habigt T Rothbucher M Diepold K 《The Journal of the Acoustical Society of America》2011,130(6):EL392-EL398
Sound source localization algorithms determine the physical position of a sound source in respect to a listener. For practical applications, a localization algorithm design has to take into account real world conditions like multiple active sources, reverberation, and noise. The application can impose additional constraints on the algorithm, e.g., a requirement for low latency. This work defines the most important constraints for practical applications, introduces an algorithm, which tries to fulfill all requirements as good as possible, and compares it to state-of-the-art sound source localization approaches. 相似文献
85.
86.
J. Timár J. Gizon A. Gizon L. Zolnai B.M. Nyakó G. Căta-Danil D. Bucurescu A.J. Boston D.T. Joss E.S. Paul A.T. Semple N.J. O'Brien C.M. Parry A.V. Afanasjev I. Ragnarsson 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):11-15
High spin states of 101Rh have been populated using the reaction 70Zn+36S at 130 MeV. γ-rays were detected with the EUROGAM2 array. New high-spin bands have been observed in this nucleus up to 45/2−, 57/2− and 65/2+ states. They have been interpreted using the Nilsson-Strutinsky cranking formalism as terminating configurations. Two of
the bands were observed up to the predicted terminating states which are built up from g9/2 protons as well as d5/2, g7/2 and h11/2 neutrons relative to a 90Zr core.
Received: 30 October 1998 相似文献
87.
John P. Sutter Thomas Connolley Tim P. Hill Houcheng Huang Doug W. Sharp Michael Drakopoulos 《Journal of synchrotron radiation》2008,15(6):584-592
Finite‐element analysis is frequently used by engineers at synchrotron beamlines to calculate the elastic deformation of a single crystal undergoing mechanical bending or thermal load. ANSYS® Workbench? software is widely used for such simulations. However, although ANSYS® Workbench? software provides useful information on the displacements, strains and stresses within the crystal, it does not yield the local reciprocal lattice vectors that would be required for X‐ray diffraction calculations. To bridge this gap, a method based on the shape functions and interpolation procedures of the software itself has been developed. An application to the double‐crystal bent Laue monochromator being designed for the I12 (JEEP) wiggler beamline at the Diamond Light Source is presented. 相似文献
88.
89.
Benjamin H. Strudwick Mark A. J. Koenis Hans J. Sanders Valentin P. Nicu Sander Woutersen Prof. Wybren Jan Buma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(54):12560-12566
Vibrational circular dichroism (VCD) studies are reported on a chiral compound in which a fullerene C60 moiety is used as an electron acceptor and local VCD amplifier for an alanine-based peptide chain. Four redox states are investigated in this study, of which three are reduced species that possess low-lying electronic states as confirmed by UV/Vis spectroelectrochemistry. VCD measurements in combination with (TD)DFT calculations are used to investigate (i) how the low-lying electronic states of the reduced species modulate the amplification of VCD signals, (ii) how this amplification depends on the distance between oscillator and amplifier, and (iii) how the spatial extent of the amplifier influences amplification. These results pave the way for further development of tailored molecular VCD amplifiers. 相似文献
90.
Steven M. Swick Tim Gebraad Dr. Leighton Jones Dr. Bo Fu Dr. Thomas J. Aldrich Prof. Kevin L. Kohlstedt Prof. George C. Schatz Prof. Antonio Facchetti Prof. Tobin J. Marks 《Chemphyschem》2019,20(20):2608-2626
Accurate single-crystal X-ray diffraction data offer a unique opportunity to compare and contrast the atomistic details of bulk heterojunction photovoltaic small-molecule acceptor structure and packing, as well as provide an essential starting point for computational electronic structure and charge transport analysis. Herein, we report diffraction-derived crystal structures and computational analyses on the n-type semiconductors which enable some of the highest efficiency organic solar cells produced to date, 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene ( ITIC ) and seven derivatives (including three new crystal structures: 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-propylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene ( ITIC-C3 ), 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(3-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene ( m -ITIC-C6 ), and 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6,7-difluoro)-indanone))-5,5,11,11-tetrakis(4-butylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene ( ITIC-C4-4F ). IDTT acceptors typically pack in a face-to-face fashion with π–π distances ranging from 3.28–3.95 Å. Additionally, edge-to-face packing is observed with S⋯π interactions as short as 3.21–3.24 Å. Moreover, ITIC end group identities and side chain substituents influence the nature and strength of noncovalent interactions (e. g. H-bonding, π–π) and thus correlate with the observed packing motif, electronic structure, and charge transport properties of the crystals. Density functional theory (DFT) calculations reveal relatively large nearest-neighbor intermolecular π-π electronic couplings (5.85–56.8 meV) and correlate the nature of the band structure with the dispersion interactions in the single crystals and core–end group polarization effects. Overall, this combined experimental and theoretical work reveals key insights into crystal engineering strategies for indacenodithienothiophene (IDTT) acceptors, as well as general design rules for high-efficiency post-fullerene small molecule acceptors. 相似文献