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排序方式: 共有915条查询结果,搜索用时 703 毫秒
41.
42.
Remote interactions between two d-dimensional distributed quantum systems: nonlocal generalized quantum control-NOT gate and entanglement swapping
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We present a systematic simple method to implement a generalized quantum control-NOT (CNOT) gate on two d-dimensional distributed systems. First, we show how the nonlocal generalized quantum CNOT gate can be implemented with unity fidelity and unity probability by using a maximally entangled pair of qudits as a quantum channel. We also put forward a scheme for probabilistically implementing the nonlocal operation with unity fidelity by employing a partially entangled qudit pair as a quantum channel. Analysis of the scheme indicates that the use of partially entangled quantum channel for implementing the nonlocal generalized quantum CNOT gate leads to the problem of 'the general optimal information extraction'. We also point out that the nonlocal generalized quantum CNOT gate can be used in the entanglement swapping between particles belonging to distant users in a communication network and distributed quantum computer.[第一段] 相似文献
43.
M. Caymax M. Houssa G. Pourtois F. Bellenger K. Martens A. Delabie S. Van Elshocht 《Applied Surface Science》2008,254(19):6094-6099
Important progress has been made in the passivation of Ge/gate dielectric interfaces. One important approach is by thermally oxidized GeO2 interface and ALD high-k layers, with an interface state density Dit ∼ 2 × 1011 cm−2 eV−1. Another approach is with an epi-Si/SiO2 interface, resulting in similar Dit. Hysteresis and Vth shift, however, are still not optimal. Extensive material characterization and theoretical insights help us understanding the root cause of these remaining issues and show the way to improved interface control. 相似文献
44.
Despite the opportunity to manipulate the water freezing via superhydrophobic materials, their commercial use for passive icing protection is still questioned, since the combined effect of surface morphology, air cushion arrangement, roughness, chemistry and film thickness on the icephobic properties of a given non-wettable solid remains unexplored. This article addresses the existing research gaps by studying the ice nucleation dynamics at the contact line of various superhydrophobic soot-based surfaces, potentially applicable in cryobiology for enhancing the existing cryopreservation technologies. We examine the freezing time and freezing temperature of water droplets settled on three groups of soot coatings with divergent morphochemical features, adjusted by modifying the samples with alcohol, fluorocarbon and/or silver hydrogen fluoride. Our results demonstrate the appearance of a new “contour” freezing mode, where the droplet shell crystallizes simultaneously with the contact interface, whilst the soot's chemical bonds along with some of its physical characteristics govern the ice formation. 相似文献
45.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献
46.
《Electrophoresis》2017,38(3-4):507-512
LIF detection often requires labeling of analytes with fluorophores; and fast fluorescent derivatization is valuable for high‐throughput analysis with flow‐gated CE. Here, we report a fast fluorescein‐labeling scheme for amino acid neurotransmitters, which were then rapidly separated and detected in flow‐gated CE. This scheme was based on the reaction between primary amines and o‐phthalaldehyde in the presence of a fluorescent thiol, 2‐((5‐fluoresceinyl)aminocarbonyl)ethyl mercaptan (FACE‐SH). The short reaction time (<30 s) was suited for on‐line mixing and derivatization that was directly coupled with flow‐gated CE for rapid electrophoretic separation and sensitive LIF detection. To maintain the effective concentration of reactive FACE‐SH, Tris(2‐carboxyethyl)phosphine was added to the derivatization reagents to prevent thiol loss due to oxidation. This labeling scheme was applied to the detection of neurotransmitters by coupling in vitro microdialysis with online derivatization and flow‐gated CE. It is also anticipated that this fluorophore tagging scheme would be valuable for on‐chip labeling of proteins retained on support in SPE. 相似文献
47.
S. M. Richardson 《Rheologica Acta》1986,25(4):372-379
The injection moulding of thermoplastics involves, during mould filling, flows of hot polymer melts into mould networks, the walls of which are so cold that frozen layers form on them. An analytical study of such flows is presented here for the case when the Graetz number is small and the Nahme number is non-zero and can be large. Thus the flows are fully-developed and temperature differences due to heat generation by viscous dissipation are sufficiently large to cause significant variations in viscosity.
Gz
Graetz number
-
h
half-height of channel or disc
-
h
*
half-height of polymer melt region in channel or disc
-
L
length of channel or pipe
-
m
viscosity shear-rate exponent
-
Na
Q
Nahme number based on flowrate
-
Na
P
Nahme number based on pressure drop
-
Na
PL
lower critical value of Nahme number based on pressure drop
-
Na
PU
upper critical value of Nahme number based on pressure drop
-
Na
P
Nahme number based on pressure gradient
-
p
pressure
-
P
pressure drop
-
Q
volumetric flowrate
-
r
radial coordinate in pipe or disc
-
R
radius of pipe
-
Re
Reynolds number
-
R
i
inner radius of disc
-
R
0
outer radius of disc
-
R
*
radius of polymer melt region in pipe
-
T
temperature
-
T
m
melting temperature of polymer
-
T
0
reference temperature
-
T
w
wall temperature
-
u
axial velocity in pipe or channel or radial velocity in disc
-
w
width of channel
-
x
axial coordinate in channel
-
y
transverse coordinate in channel or disc
-
z
axial coordinate in pipe
-
thermal conductivity of molten polymer
-
thermal conductivity of frozen polymer
-
heat capacity of molten polymer
-
viscosity temperature exponent
-
dimensionless transverse coordinate in channel or disc
-
*
dimensionless half-height of polymer melt region in channel or disc
-
dimensionless temperature
-
*
dimensionless wall temperature
-
µ
viscosity of molten polymer
-
µ
0
consistency of molten polymer
-
dimensionless pressure drop
-
dimensionless pressure gradient
-
density of molten polymer
-
dimensionless radial coordinate in pipe or disc
-
i
dimensionless inner radius of disc
-
*
dimensionless radius of polymer melt region in pipe
-
dimensionless velocity 相似文献
48.
S. M. Richardson 《Rheologica Acta》1986,25(2):180-190
The injection moulding of thermoplastics involves, during mould filling, flows of hot polymer melts into mould networks, the walls of which are so cold that frozen layers form on them. An analytical study of such flows is presented here for the case when the Graetz and Nahme numbers are large and the Pearson number is small. Thus the flows are developing and temperature differences due to heat generation by viscous dissipation are sufficiently large to cause significant variations in viscosity (but the difference between the entry temperature of the polymer to a specific part of the mould network and the melting temperature of the polymer is not).
Br
Brinkman number
-
Gz
Graetz number
-
h
half-height of channel or disc
-
h
*
half-height of polymer melt region in channel or disc
-
L
length of channel or pipe
-
m
viscosity shear-rate exponent
-
Na
Nahme number
-
p
pressure
-
P
pressure drop
-
Pe
Péclet number
-
Pn
Pearson number
-
Q
volumetric flowrate
-
r
radial coordinate in pipe or disc
-
R
radius of pipe
-
Re
Reynolds number
-
R
i
inner radius of disc
-
R
o
outer radius of disc
-
R
*
radius of polymer melt region in pipe
-
T
temperature
-
T
ad
adiabatic temperature rise
-
T
e
entry polymer melt temperature
-
T
m
melting temperature of polymer
-
T
max
maximum temperature
-
T
0
reference temperature
-
T
w
wall temperature
-
flow-average temperature rise
-
u
r
radial velocity in pipe or disc
-
u
x
axial velocity in channel
-
u
y
transverse velocity in channel or disc
-
u
z
axial velocity in pipe
-
w
width of channel
-
x
axial coordinate in channel or modified radial coordinate in disc
-
y
transverse coordinate in channel or disc
-
z
axial coordinate in pipe
-
thermal conductivity of molten polymer
-
thermal conductivity of frozen polymer
-
scaled dimensionless axial coordinate in channel or pipe or radial coordinate in disc
-
0
undetermined integration constant
-
heat capacity of molten polymer
-
viscosity temperature exponent
-
dimensionless transverse coordinate in channel or disc
-
*
dimensionless half-height of polymer melt region in channel or disc
-
H
*
scaled dimensionless half-height of polymer melt region in channel or disc or radius of polymer melt region in pipe
-
dimensionless temperature
-
*
dimensionless wall temperature
-
scaled dimensionless temperature
-
numerical constant
-
µ
viscosity of molten polymer
-
µ
0
consistency of molten polymer
-
dimensionless pressure gradient
-
scaled dimensionless pressure gradient
-
density of molten polymer
-
dimensionless radial coordinate in pipe or disc
-
i
dimensionless inner radius of disc
-
*
dimensionless radius of polymer melt region in pipe
-
dimensionless streamfunction
-
scaled dimensionless streamfunction
-
dummy variable
-
streamfunction
-
similarity variable
-
similarity variable 相似文献
49.
50.
Silicon oxide (SiO2) and silicon oxynitride (SiOxNy) are two key dielectrics used in silicon devices. The excellent interface properties of these dielectrics with silicon have enabled the tremendous advancement of metal-oxide-semiconductor (MOS) technology. However, these dielectrics are still found to have pronounced amount of localized states which act as electron or hole traps and lead to the performance and reliability degradations of the MOS integrated circuits. A better understanding of the nature of these states will help to understand the constraints and lifetime performance of the MOS devices. Recently, due to the available of ab initio quantum-mechanical calculations and some synchrotron radiation experiments, substantial progress has been achieved in understanding the atomic and electronic nature of the defects in these dielectrics. In this review, the properties, formation and removal mechanisms of various defects in silicon oxide and silicon oxynitride films will be critically discussed. Some remarks on the thermal ionization energies in connection with the optical ionization energies of electron and hole traps, as well as some of the unsolved issues in these materials will be highlighted. 相似文献