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991.
We have calculated the one-neutron absorption cross-section and the longitudinal momentum distribution of the core fragment
coming out from the breakup of 11Be and 19C on 9Be target at 63 MeV/A and 88 MeV/A beam energies respectively. The reaction mechanism is treated within the framework of the
eikonal approximation. The effective range of the nuclear interaction between the core and the valence neutron within the
projectile has been determined by comparing the predicted stripping cross-section with the recently measured one. The effective
range for 19C has been found to be smaller than that for 11Be. It qualitatively indicates that 19C is slightly more halo than 11Be. The smaller width, predicted as well as measured, of the LMD of 18C than 10Be also strengthens this fact. The experimental data concerning the LMD of core fragments have been well represented.
相似文献
992.
Marco Castrillón López Jaime Muñz Masquó 《International Journal of Theoretical Physics》2007,46(4):1020-1026
It is proved that the Euler–Lagrange equations of a Yang-Mills type Lagragian is independent with respect to the chosen pairing
in the Lie algebra. Moreover, the Hamilton-Cartan equations of these Lagrangians are obtained and proved to be also independent
with respect to the pairing.
PACS Numbers 2003: 02.20.Qs, 02.20.Sv, 02.20.Tw, 02.40.Ma, 02.40.Vh, 11.10.Ef, 11.15.Kc
Mathematics Subject Classification 2000: Primary 70S15, Secondary 58A20, 58E15, 58E30, 70S05, 70S10, 81T13 相似文献
993.
We present the study of exact inhomogeneous cosmological solutions to a four-dimensional low energy limit of string theory
containing non-minimal interacting electromagnetic, dilaton and axion fields. We focus at Einstein-Rosen solutions of Einstein-Maxwell-dilaton-axion
equations. Several cases are analyzed and some of them have asymptotically velocity-term dominated (AVTD) singularities. 相似文献
994.
Anirudh Pradhan Purnima Pandey Kanti Jotania Mahesh Kumar Yadav 《International Journal of Theoretical Physics》2007,46(11):2774-2787
Plane symmetric viscous fluid cosmological models of the universe with a variable cosmological term are investigated. The
viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear
viscosity is to be proportional to rate of expansion in the model. We have also obtained a special model in which the shear
viscosity is assumed to be zero. The cosmological constant Λ is found to be a decreasing function of time and a positive which is supported by results from recent supernovae Ia observations.
Some physical and geometric properties of the models are also discussed. 相似文献
995.
Anjan Biswas Swapan Konar Essaid Zerrad 《International Journal of Theoretical Physics》2007,46(1):157-169
The intra-channel collision of optical solitons, with dual-power law nonlinearity, is studied in this paper by the aid of
quasi-particle theory. The perturbation terms that are considered in this paper are the nonlinear gain and saturable amplifiers
along with filters. The suppression of soliton-soliton interaction, in presence of these perturbation terms, is acheived.
The numerical simulations support the quasi-particle theory.
OCIS codes: 060.2310; 060.4510; 060.5530; 190.3270; 190.4370. 相似文献
996.
A theoretical framework is demonstrated to evaluate the degree of entanglement of bit states in quantum computing. Separability
of general superposition of Hilbert space unit vectors is discussed, and criteria in amplitude as well as in phase are derived.
By these criteria the possibility of different quantum gates such as controlled not (CN), controlled controlled not (CCN),
controlled rotation (CR), and controlled phase shift (CPS), to create the entanglement is examined. Furthermore, the selection
of measurement mode external to the quantum system is incorporated in the formula using Kronecker delta (δ
kx
), introducing the concept of dynamic entanglement. With this the process of wavefunction collapse upon measurement is understood as the result of the activation of the dynamic
entanglement. A firefly in a box model is used to show a pure state of ontological uncertainty, which is in a dynamically
entangled state in Hilbert space. 相似文献
997.
N. Sankara Subramanian R. Vivek Sabaapathy P. Vickraman G. Vimal Kumar R. Sriram B. Santhi 《Ionics》2007,13(5):323-328
P-type porous silicon (PS) structure has been prepared by anodic electrochemical etching process under optimized conditions.
Photoluminescence studies of the PS structure show emission at longer wavelengths (red) for the excitation at 365 nm. Scanning
electron microscope investigations of the PS surface confirm the formation of uniform porous structure, and the pore diameter
have been estimated as 25 μm. Pd:SnO2/PS/p-Si heterojunction with top gold ohmic contact developed by conventional methods has been used as the sensor device.
Sensing properties of the device towards liquefied petroleum gas (LPG) and NO2 gas have been investigated in an indigenously developed sensor test rig. The response and recovery characteristics of the
sensor device at different operating temperatures show short response time for LPG. From the studies, maximum sensitivity
and optimum operating temperature of the device towards LPG and NO2 gas sensing has been estimated as 69% at 180 °C and 52% at 220 °C, respectively. The developed sensor device shows a short
response time of 25 and 57 s for sensing LPG and NO2 gases, respectively.
Paper presented at the Third International Conference on Ionic Devices (ICID 2006), Chennai, Tamilnadu, India, Dec. 7–9, 2006. 相似文献
998.
Tetsuya Hattori 《Journal of statistical physics》2007,127(3):609-627
Let W(x,y) = ax
3+ bx
4+ f
5
x
5+ f
6
x
6+ (3 ax
2)2
y+ g
5
x
5
y + h
3
x
3
y
2 + h
4
x
4
y
2 + n
3
x
3
y
3+a
24
x
2
y
4+a
05
y
5+a
15
xy
5+a
06
y
6, and X = , , where the coefficients are non-negative constants, with a > 0, such that X
2(x,x
2)−Y(x,x
2) is a polynomial of x with non-negative coefficients.
Examples of the 2 dimensional map Φ: (x,y)↦ (X(x,y),Y(x,y)) satisfying the conditions are the renormalization group (RG) maps (modulo change of variables) for the restricted self-avoiding
paths on the 3 and 4 dimensional pre-gaskets.
We prove that there exists a unique fixed point (x
f
,y
f
) of Φ in the invariant set .
2000 Mathematics Subject Classification Numbers: 82B28; 60G99; 81T17; 82C41. 相似文献
999.
A parallel plate interferometer with a reflecting mirror for measuring angular displacement is proposed. A deflection angle
of a beam caused by an angular displacement is amplified by use of a reflecting mirror to increase the optical path difference
(OPD) in the plane-parallel plate, which provides high sensitivity of the phase measurement. Detection of light transmitted
through the plane-parallel plate with a position sensitive detector (PSD) enables high accurate measurement of the initial
angle of incidence to the plane-parallel plate with insensitivity to stray light. The improved parallel plate interferometer
achieves a measurement repeatability of 10−8 rad. 相似文献
1000.
Phospholipid lung surfactant and nanoparticle surface toxicity: Lessons from diesel soots and silicate dusts 总被引:3,自引:0,他引:3
William E. Wallace Michael J. Keane David K. Murray William P. Chisholm Andrew D. Maynard Tong-man Ong 《Journal of nanoparticle research》2007,9(1):23-38
Because of their small size, the specific surface areas of nanoparticulate materials (NP), described as particles having at
least one dimension smaller than 100 nm, can be large compared with micrometer-sized respirable particles. This high specific
surface area or nanostructural surface properties may affect NP toxicity in comparison with micrometer-sized respirable particles
of the same overall composition. Respirable particles depositing on the deep lung surfaces of the respiratory bronchioles
or alveoli will contact pulmonary surfactants in the surface hypophase. Diesel exhaust ultrafine particles and respirable
silicate micrometer-sized insoluble particles can adsorb components of that surfactant onto the particle surfaces, conditioning
the particles surfaces and affecting their in vitro expression of cytotoxicity or genotoxicity. Those effects can be particle surface composition-specific. Effects of particle
surface conditioning by a primary component of phospholipid pulmonary surfactant, diacyl phosphatidyl choline, are reviewed
for in vitro expression of genotoxicity by diesel exhaust particles and of cytotoxicity by respirable quartz and aluminosilicate kaolin
clay particles. Those effects suggest methods and cautions for assaying and interpreting NP properties and biological activities. 相似文献