The Hirota's bilinear direct method is applied to constructing
soliton solutions to a special coupled modified Korteweg-de Vries
(mKdV) system. Some physical properties such as the spatiotemporal
evolution, waveform structure, interactive phenomena of solitons are
discussed, especially in the two-soliton case. It is found that
different interactive behaviours of solitary waves take place under
different parameter conditions of overtaking collision in this
system. It is verified that the elastic interaction phenomena exist
in this (1+1)-dimensional integrable coupled model.

Based on the B?cklund method and the multilinear variable
separation approach (MLVSA), this paper finds a general solution
including two arbitrary functions for the (2+1)-dimensional Burgers
equations. Then a class of new doubly periodic wave solutions for
(2+1)-dimensional Burgers equations is obtained by introducing
appropriate Jacobi elliptic functions, Weierstrass elliptic
functions and their combination in the general solutions (which
contains two arbitrary functions). Two types of limit cases are
considered. Firstly, taking one of the moduli to be unity and the
other zero, it obtains particular wave (called semi-localized)
patterns, which is periodic in one direction, but localized in the
other direction. Secondly, if both moduli are tending to 1 as a
limit, it derives some novel localized excitations (two-dromion
solution).

This paper focuses on studying Noether symmetries and conservation
laws of the discrete mechanico-electrical systems with the
nonconservative and the dissipative forces. Based on the invariance
of discrete Hamilton action of the systems under the infinitesimal
transformation with respect to the generalized coordinates, the
generalized electrical quantities and time, it presents the discrete
analogue of varitional principle, the discrete analogue of
Lagrange-Maxwell equations, the discrete analogue of Noether
theorems for Lagrange-Maxwell and Lagrange machanico-electrical
systems. Also, the discrete Noether operator identity and the
discrete Noether-type conservation laws are obtained for these
systems. An actual example is given to illustrate these results.

This paper studies the Lie symmetry and Hojman conserved quantity of
Nambu system. The determining equations of Lie symmetry for the
system are given. The conditions for existence and the form of the
Hojman conserved quantity led by the Lie symmetry for the system are
obtained. Finally, an example is given to illustrate the application
of the results.

For a Birkhoffian system in the event space, this paper presents the
Routh method of reduction. The parametric equations of the
Birkhoffian system in the event space are established, and the
definition of cyclic coordinates for the system is given and the
corresponding cyclic integral is obtained. Through the cyclic
integral, the order of the system can be reduced. The Routh
functions for the Birkhoffian system in the event space are
constructed, and the Routh method of reduction is successfully
generalized to the Birkhoffian system in the event space. The
results show that if the system has a cyclic integral, then the
parametric equations of the system can be reduced at least by two
degrees and the form of the equations holds. An example is given to
illustrate the application of the results.

This paper constructs the new common eigenvectors of n
intermediate coordinate-momentum operators which are complete and
orthonormal. The intermediate coordinate-momentum representation of
a multi-particles system is proposed and applied to a general
n-mode quantum harmonic oscillators system with coordinate-momentum
coupling.

In a recent paper [Phys. Rev. A 76 042313 (2007)],
Sainz and Bjork introduced an entanglement invariant $\mathcal{E}$
under evolution for a system of four qubits interacting through two
isolated Jaynes-Cummings Hamiltonians. This paper proves that this
entanglement invariant $\mathcal{E}$ is closely connected with the
linear entropy between two independent subsystems.

This paper applies the analytical transfer matrix method (ATMM) to
calculate energy eigenvalues of a particle in low dimensional sharp
confining potential for the first time, and deduces the quantization
rules of this system. It presents three cases in which the applied
method works very well. In the first quantum dot, the energy
eigenvalues and eigenfunction are obtained, and compared with those
acquired from the exact numerical analysis and the WKB (Wentzel,
Kramers and Brillouin) method; in the second or the third case, we
get the energy eigenvalues by the ATMM, and compare them with the
EBK (Einstein, Brillouin and Keller) results or the wave function
outcomes. From the comparisons, it finds that the semiclassical
method (WKB, EBK or wave function) is inexact in such systems.

This paper proposes a scalable scheme to generate n-atom GHZ
states and cluster states by using the basic building block, i.e., a
weak coherent optical pulse |α> being
reflected successively from a single-atom cavity. In the schemes,
coherent state of light is used instead of single photon source,
homodyne measurement on coherent light is done instead of single
photon detection, and no need for individually addressing keeps the
schemes easy to implement from the experimental point of view. The
successful probabilities of our protocols approach unity in the
ideal case.

This paper presents a direct implementation scheme of the
non-local multi-qubit controlled phase gate by using optical fibers
and adiabatic passage. The smaller operation number for implementing
the multi-qubit controlled phase gate and needlessness for
addressing individually save physical resource and lower the
difficulties of experiment. Meanwhile, the scheme is immune from
some decoherence effects such as the atomic spontaneous emission and
the fibers loss. In principle, it is scalable.

Transcription factor binding sites (TFBS) play key roles in gene's
expression and regulation. They are short sequence segments with
definite structure and can be recognized by the corresponding
transcription factors correctly. From the viewpoint of statistics,
the candidates of TFBS should be quite different from the segments
that are randomly combined together by nucleotide. This paper
proposes a combined statistical model for finding over-represented
short sequence segments in different kinds of data set. While the
over-represented short sequence segment is described by position
weight matrix, the nucleotide distribution at most sites of the
segment should be far from the background nucleotide distribution.
The central idea of this approach is to search for such kind of
signals. This algorithm is tested on 3 data sets, including binding
sites data set of cyclic AMP receptor protein in E.coli, PlantProm
DB which is a non-redundant collection of proximal promoter
sequences from different species, collection of the intergenic
sequences of the whole genome of E.Coli. Even though the complexity
of these three data sets is quite different, the results show that
this model is rather general and sensible.

This paper analyzes the dispersion relation of the excitation mode in non-relativistic interacting fermion matter. The polarization tensor is calculated with the random phase approximation in terms of finite temperature field theory. With the polarization tensor, the influences of temperature,particle number density and interaction strength on the dispersion relation are discussed in detail.
It finds that the collective effects are qualitatively more important in the unitary fermions than those in the finite contact interaction matter.

This paper is devoted to investigating the scheme of exponential
synchronization for uncertain stochastic impulsive perturbed chaotic
Lur'e systems. The parametric uncertainty is assumed to be norm
bounded. Based on the Lyapunov function method, time-varying delay
feedback control technique and a modified Halanay inequality for
stochastic differential equations, several sufficient conditions are
presented to guarantee the exponential synchronization in mean
square between two identical uncertain chaotic Lur'e systems with
stochastic and impulsive perturbations. These conditions are
expressed in terms of linear matrix inequalities (LMIs), which can
easily be checked by utilizing the numerically efficient Matlab LMI
toolbox. It is worth pointing out that the approach developed in
this paper can provide a more general framework for the
synchronization of multi--perturbation chaotic Lur'e systems, which
reflects a more realistic dynamics. Finally, a numerical example is
provided to demonstrate the effectiveness of the proposed method.

Coexistence of attractors with striking characteristics is observed
in this work, where a stable period-5 attractor coexists
successively with chaotic band-11, period-6, chaotic band-12 and
band-6 attractors. They are induced by different mechanisms due to
the interaction between the discontinuity and the non-invertibility.
A characteristic boundary collision bifurcation, is observed. The
critical conditions are obtained both analytically and numerically.

This paper studies the multiscale entropy (MSE) of
electrocardiogram's ST segment and compares the MSE results of ST
segment with that of electrocardiogram in the first time.
Electrocardiogram complexity changing characteristics has important
clinical significance for early diagnosis. Study shows that the
average MSE values and the varying scope fluctuation could be more
effective to reveal the heart health status. Particularly the
multiscale values varying scope fluctuation is a more sensitive
parameter for early heart disease detection and has a clinical
diagnostic significance.

This paper presents theoretical computations of the ionization rate
of Rydberg lithium atom above the classical ionization threshold
using semiclassical approximation. The yielded random pulse trains
of the escape electrons are recorded as a function of emission time
such that allow for relating themselves to the terms of the
recurrence periods of the photoabsorption. This fact turns to
illustrate that it is ionic core scattering processes which give
rise to chaos in autoionization dynamics and are verified by
comparison of our results with the hydrogen atom situation readily.
In order to reveal the chaotic properties in detail, the sensitive
dependence of the ionization rate upon the scaled energy is
discussed for different scaled energies. This approach provides a
simple explanation for the chaotic character in autoionization decay
of Rydberg alkali-metal atoms.

This paper focuses on sliding mode control problems for a class of
nonlinear neutral systems with time-varying delays. An integral
sliding surface is firstly constructed. Then it finds a useful
criteria to guarantee the global stability for the nonlinear neutral
systems with time-varying delays in the specified switching surface,
whose condition is formulated as linear matrix inequality. The
synthesized sliding mode controller guarantees the reachability of
the specified sliding surface. Finally, a numerical simulation
validates the effectiveness and feasibility of the proposed
technique.

This paper studies the effect of adaptive cruise control (ACC)
system on traffic flow by using simulations. The multiple headway
and velocity difference (MHVD) model is used to depict the motion of
ACC vehicles, and the simulation results are compared with the
optimal velocity (OV) model which is used to depict the motion of
manual vehicles. Compared the cases between the manual and the ACC
vehicle flow, the fundamental diagram can be classified into four
regions: I, II, III, IV. In low and high density the flux of the two
models is the same; in region II the free flow region of the MHVD
model is enlarged, and the flux of the MHVD model is larger than
that of the OV model; in region III serious jams occur in the OV
model while the ACC system suppresses the jams in the MHVD model and
the traffic flow is in order, but the flux of the OV model is larger
than that of the MHVD model. Similar phenomena also appeared in
mixed traffic flow which consists of manual and ACC vehicles. The
results indicate that ACC vehicles have significant effect on
traffic flow. The improvement induced by ACC vehicles decreases with
the increasing proportion of ACC vehicles.

Based on the optimal velocity models, an extended model is proposed,
in which multi-velocity-difference ahead is taken into
consideration. The damping effect of the multi-velocity-difference
ahead has been investigated by means of analytical and numerical
methods. Results indicate that the multi-velocity-difference leads
to the enhancement of stability of traffic flow, suppression of the
emergence of traffic jamming, and reduction of the energy
consumption.

In this paper, the effect of imperfect channel state information at
the receiver, which is caused by noise and other interference, on
the multi-access channel capacity is analysed through a
statistical-mechanical approach. Replica analyses focus on
analytically studying how the minimum mean square error (MMSE)
channel estimation error appears in a multiuser channel capacity
formula. And the relevant mathematical expressions are derived. At
the same time, numerical simulation results are demonstrated to
validate the Replica analyses. The simulation results show how the
system parameters, such as channel estimation error, system load and
signal-to-noise ratio, affect the channel capacity.

This paper is devoted to the study of consensus problems for the
second-order multi-agent systems with external disturbances,
switching topology and communication time-delay. Firstly, we perform
a model transformation and separate the agreement states from the
disagreement states. Secondly, according to this system, we derive a
sufficient condition for consensus problem without disturbances by
using the Lyapunov-based approach. Furthermore, we give a design
criterion in terms of bilinear matrix inequality for the control
protocol in the presence of disturbances. Finally, numerical
simulations are provided to show the effectiveness of our
strategies.

This paper describes a newly designed gamma pulse detector of
current mode that uses the scattered electron method. Tungsten is
used as the scattering target, an organic thin film scintillator
ST401 is used to collect the scattered electrons. The spatial
distribution of the electronic energy-flux density is studied by
using the MCNP code. The optimization of the target and the
thickness of the scintillator are also discussed. The results
indicate that the energy response is relatively flat in the range of
0.4 to 5 MeV.

Based on the meson-meson mixing and Regge trajerory, this paper
establishes the mass relations which can describe the mass spectrum
of ^{1}1P_{1} meson state. Using these mass relations, it obtains the
mass of K_{1B}, h_{1}(1380) and h_{c}(1P) to be 1358.5MeV,
1468MeV and 3543.9MeV, respectively. The results are compared
with other theoretical results and should be tested by experiments
in the future.

This paper has calculated that Rydberg atoms can be transferred to
states of lower principal quantum number by exposing them to a
frequency chirped microwave pulse. The atoms experience the
consequence: 70p-69s-68p-67s-66p by a constant amplitude field in
the adopted model. This study shows that the complete population
transfer is related to the chirp rate and the carrier frequency.

This paper applies the
symmetry-adapted-cluster/symmetry-adapted-cluster
configuration-interaction (SAC/SAC-CI) method to optimize the
structures for X^{1}∑^{+}, A^{1}∏ and C^{1}∑^{-} states of
SiO molecule with the basis sets D95++, 6-311++G and 6-311++G**.
Comparing the obtained results with the experiments, it gets the
conclusion that the basis set 6-311++G** is most suitable for the
optimal structure calculations of X^{1}∑^{+}, A^{1}∏ and
C^{1}∑^{-} states of SiO molecule. The whole potential energy
curves for these electronic states are further scanned by using
SAC/6-311++G** method for the ground state and SAC-CI/6-311++G**
method for the excited states, then use a least square method to fit
Murrell--Sorbie functions, at last the spectroscopic constants and
force constants are calculated, which are in good agreement with the
experimental data.

This paper reports that the absorption spectra of H_{2}O^{+}
have been measured by tunable mid-infrared diode laser spectroscopy
in the spectral range of 1100--1380cm^{-1}. The H_{2}O^{+} ions are generated in an AC glow discharge of the gaseous
mixtures of H_{2}O/He and detected with the velocity modulation
technique. Forty new lines are assigned to the μ_{2}
fundamental band of H_{2}O^{+} (\tilde {X}^{2}B_{1} )1. The
observed lines together with other data published previously are
fitted to the standard effective Hamiltonian of an asymmetric top,
yielding a set of improved rotational constants, spin-rotation
constants and their quartic and sextic centrifugal distortion
constants for the μ_{2}=1 vibrational state of H_{2}O^{+}.

The photoelectron energy spectra (PESs) excited by monochromatic
femtosecond x-ray pulses in the presence of a femtosecond laser are
investigated. A PES is composed of a set of separate peaks, showing
interesting comb-like structures. These structures result from the
quantum interferences between photoelectron wave packets generated
at different times. The width and the localization of each peak as
well as the number of peaks are determined by all the laser and
x-ray parameters. Most of peak heights of the PES are higher than
the classical predictions.

The density functional theory (DFT) method (b3p86) of Gaussian 03 is
used to optimize the structure of the Ni_{2} molecule. The result
shows that the ground state for the Ni_{2} molecule is a
5-multiple state, symbolising a spin polarization effect existing in
the Ni_{2} molecule, a transition metal molecule, but no spin
pollution is found because the wave function of the ground state
does not mingle with wave functions of higher-energy states. So the
ground state for Ni_{2} molecule, which is a 5-multiple state, is
indicative of spin polarization effect of the Ni_{2} molecule,
that is, there exist 4 parallel spin electrons in Ni_{2} molecule.
The number of non-conjugated electrons is greatest. These electrons
occupy different spatial orbitals so that the energy of the Ni_{2}
molecule is minimized. It can be concluded that the effect of
parallel spin in the Ni_{2} molecule is larger than that of the
conjugated molecule, which is obviously related to the effect of
electron d delocalization. In addition, the Murrell-Sorbie potential
functions with the parameters of the ground state and other states
of the Ni_{2} molecule are derived. The dissociation energy
D_{e} for the ground state of the Ni_{2} molecule is
1.835eV, equilibrium bond length R_{e} is 0.2243\,nm,
vibration frequency \omega_{e} is 262.35cm^{-1}. Its
force constants f_{2}, f_{3} and f_{4} are 1.1901aJ.nm^{2},
--5.8723aJ.nm^{-3}, and 21.2505\,aJ.nm^{-4} respectively.
The other spectroscopic data for the ground state of the Ni_{2}
molecule \omega_{e}\chi_{e}, B_{e} and \alpha_{e} are 1.6315cm^{-1}, 0.1141\,cm^{-1}, and
8.0145x10^{-4}cm^{-1} respectively.

This paper proposes a novel one-color Xe-Kr laser induced
collisional ionization system. Considering the level scheme of the
system, it finds that the initial state of the reaction--the four 4f
levels with even J of Xe--can be prepared through method of
four-photon resonant excitation by dye laser with wavelength of
～440nm. Absorption of an additional photon (the transfer
laser) of the same wavelength will complete the laser induced
collisional ionization process. The resonance enhanced ionization
spectrum of Xe by four laser photons at ～440nm is measured
through time-of-flight mass spectrometry, this aims at the
preparation of the initial state of the system proposed. The Stark
broadening of the measured spectrum is observed and consistent with
the previous study. Analysis of the measured resonance ionization
spectrum implies the feasibility of ～440nm four-photon
resonant excitation of the initial 4f state of the Xe-Kr system
proposed in this paper, which prepares for a further experiment of
laser induced collisional ionization.

A scheme for third-order ghost interference with thermal light is
proposed. The visibility and resolution of the interference fringe
related to the bandwidth of the spatial frequency spectrum of the
source are analyzed. The results show that the visibility of the
third-order ghost interference fringe is much higher than that of
the second-order one.

The period-one oscillation produced by an external optical pulse
injection driven semiconductor laser is applied to clock recovery
and frequency division. By adjusting the repetition rate or
injection power of the external injection optical pulses to lock the
different harmonic frequencies of the period-one state, the clock
recovery and the frequency division (the second and third frequency
divisions) are achieved experimentally. In addition, in frequency
locking ranges of 2GHz and 1.9GHz, the second and third
frequency divisions are obtained with the phase noise lower than
--100dBc/Hz, respectively. Our experimental results are consistent
well with the numerical simulations.

The photon emission spectrum of the hydrogen atoms in an intense
high-frequency laser pulse is simulated by using one-dimensional
soft Coulomb potential. Regular fine structures appear on the two
sides of both the odd and even multiples of photon energy of the
laser field besides the ordinary odd harmonic peaks. It is proved
that the splits of the fine structures are responsible for
hyper-Raman lines and the energy spacing between the odd harmonic
lines is equal to the difference in energy between the eigenstates
with the same parity of the time averaged Krameters-Henneberger (KH)
potential. By analysing the features of the fine structures, we also
verify that the so-called even order harmonics under the
stabilization condition are indeed hyper-Raman lines caused by the
transitions between the dressed atomic states with different values
of parity.

In order to obtain a clear image of the retina of model eye, an
adaptive optics system used to correct the wave-front error is
introduced in this paper. The spatial light modulator that we use
here is a liquid crystal on a silicon device instead of a
conversional deformable mirror. A paper with carbon granule is used
to simulate the retina of human eye. The pupil size of the model eye
is adjustable (3--7mm). A Shack-Hartman wave-front sensor is used
to detect the wave-front aberration. With this construction, a value
of peak-to-valley is achieved to be 0.086Λ, where
Λ is wavelength. The modulation transfer functions before
and after corrections are compared. And the resolution of this
system after correction (69lp/m) is very close to the diffraction
limit resolution. The carbon granule on the white paper which has a
size of 4.7μm is seen clearly. The size of the retina cell is
between 4 and 10μm. So this system has an ability to image
the human eye's retina.

Application of the pressure controlled isothermal heating vertical
deposition method to the fabrication of colloidal photonic crystals
is systematically investigated in this paper. The fabricated samples
are characterized by scanning electron microscope and transmission
spectrum. High-quality samples with large transmissions in the pass
bands and the sharp band edges are obtained and the optimum growth
condition is determined. For the best sample, the transmission in
the pass bands approaches 0.9 while that in the band gap reaches
0.1. More importantly, the maximum differential transmission as high
as 0.1/nm is achieved. In addition, it is found that the number of
stacking layers does not increase linearly with concentration of PS
spheres in a solution, and a gradual saturation occurs when the
concentration of PS spheres exceeds 1.5 wt.%. The uniformity of
the fabricated samples is examined by transmission measurements on
areas with different sizes. Finally, the tolerance of the fabricated
samples to baking was studied.

Fluid manipulation is very important in lab-on-a-chip system. This
paper analyzes phenomena which use the alternating current (AC)
electric field to deflect and manipulate coflowing streams of two
different electrolytes (with conductivity gradient) within a
microfluidic channel. The basic theory of the electrohydrodynamics
and simulation of the analytical model are used to explain the
phenomena. The velocity induced for different voltages and
conductivity gradient are computed. The results show that when the
AC electrical signal is applied on the electrodes, the fluid with
higher conductivity occupies a larger region of the channel and the
interface of the two fluids is deflexed. It will provide some basic
references for the people who want to do more study in the control
of diffrent fluids with conductivity gradient in microfluidic
channel.

The collision efficiency in the Brownian coagulation is
investigated. A new mechanical model of collision between two
identical spherical particles is proposed, and a set of
corresponding collision equations is established. The equations are
solved numerically, thereby obtaining the collision efficiency for
the monodisperse dioctyl phthalate spherical aerosols with diameters
ranging from 100 to 760nm in the presence of van der Waals force
and the elastic deformation force. The calculated collision
efficiency, in agreement with the experimental data qualitatively,
decreases with the increase of particle diameter except a small peak
appearing in the particles with a diameter of 510nm. The results
show that the interparticle elastic deformation force cannot be
neglected in the computation of particle Brownian coagulation.
Finally, a set of new expressions relating collision efficiency to
particle diameter is established.

This paper studies the roughness effect combining with effects of
rarefaction and compressibility by a lattice Boltzmann model for
rarefied gas flows at high Knudsen numbers. By discussing the effect
of the tangential momentum accommodation coefficient on the rough
boundary condition, the lattice Boltzmann simulations of nitrogen
and helium flows are performed in a two-dimensional microchannel
with rough boundaries. The surface roughness effects in the
microchannel on the velocity field, the mass flow rate and the
friction coefficient are studied and analyzed. Numerical results for
the two gases in micro scale show different characteristics from
macroscopic flows and demonstrate the feasibility of the lattice
Boltzmann model in rarefied gas dynamics.

PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES

In order to understand the recycling and emission processes of
hydrogen atoms in HT--7, spectral profiles of the
D_{α}H_{α} line emitted in front of the limiter have
been observed with a high-resolution spectrometer and simulated by
using the neutral particle transport code DEGAS 2. The results show
that four processes are necessary to interpret the
D_{α}H_{α} line shape: 1) atom desorption, 2)
molecular dissociation, 3) particle reflection, and 4)
charge-exchange. The products of the first two processes are cold
atoms which emit photons near the peak of D_{α}H_{α} line shape, and those from the last two are warm atoms
contributing to the blue side of the spectrum. For a typical ohmic
discharge (shot 68520 n_{e} (0)≈3x10^{19}m^{-3},
these components contribute 32%, 15%, 32% and 21%,
respectively. D_{α}H_{α} line shapes under
different plasma parameters are also discussed in this paper.

A cold dielectric barrier discharge (DBD) plasma plume with one
highly conductive liquid electrode has been developed to treat
thermally sensitive materials, and its preliminary discharging
characteristics have been studied. The averaged electron temperature
and density is estimated to be 0.6eV and 10^{11}/cm^{3},
respectively. The length of plasma plume can reach 5cm with helium
gas (He), and the conductivity of the outer electrode affects the
plume length obviously. This plasma plume could be touched by bare
hand without causing any burning or painful sensation, which may
provide potential application for safe aseptic skin care. Moreover,
the oxidative particles (e.g., OH, O*, O_{3}) in the downstream
oxygen (O_{2}) gas of the plume have been applied to treat the
landfill leachate. The results show that the activated O_{2} gas
can degrade the landfill leachate effectively, and the chemical
oxygen demand (COD), conductivity, biochemical oxygen demand (BOD),
and suspended solid (SS) can be decreased by 52%，57%，76%
and 92%, respectively.

CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES

This paper reports that at a newly constructed small-angle x-ray
scattering station of Beijing Synchrotron Radiation Facility, the
topological shape of ligand--free bovine serum albumin in solution
has been investigated. An appropriate scattering curve is obtained
and the calculated value of the gyration radius is 31.2?±0.25? (1?=0.1nm) which is coincident with other ones'
results. It finds that the low-resolution structure models obtained
by making use of ab initio reconstruction methods are
fitting the crystal structure of human serum albumin very well. All
of these results perform the potential of the beamline to apply to
structural biology studies. The characteristics, the defects, and
the improving measures of the station in future are also discussed.

Scanning tunneling microscopy is utilized to investigate the
local-bias- voltage-dependent transformation between (2x1)
and c(4x2) structures on Ge(001) surfaces, which is
reversibly observed at room temperature and a critical bias voltage
of -0.80V. Similar transformation is also found on an epitaxial
Ge islands but at a slightly different critical bias voltage of
-1.00V. It is found that the interaction between the topmost
atoms on the STM tip and the atoms of the dimers, and the pinning
effect induced by Sb atoms, the vacancies or the epitaxial clusters,
can drive the structural transformation at the critical bias
voltage.

Large scale, high density boron carbide nanowires have been
synthesized by using an improved carbothermal reduction method with
B/B_{2}O_{3}/C powder precursors under an argon flow at
1100℃. The boron carbide nanowires are 5--10μm in
length and 80--100nm in diameter. Transmission electron microscopy
(TEM) and selected area electron diffraction (SAED)
characterizations show that the boron carbide nanowire has a
B_{4}C rhombohedral structure with good crystallization. The Raman
spectrum of the as-grown boron carbide nanowires is consistent with
that of a B_{4}C structure consisting of B_{11}C icosahedra and
C-B-C chains. The room temperature photoluminescence spectrum of the
boron carbide nanowires exhibits a visible range of emission centred
at 638nm.

The interaction between a wedge disclination dipole and an elastic
annular inclusion is investigated. Utilizing the Muskhelishvili
complex variable method, the explicit series form solutions of the
complex potentials in the matrix and the inclusion region are
derived. The image force acting on the disclination dipole center is
also calculated. The influence of the location of the disclination
dipole and the thickness of the annular inclusion as well as the
elastic dissimilarity of materials upon the equilibrium position of
the disclination dipole is discussed in detail. The results show
that a stable equilibrium point of the disclination dipole near the
inclusion is found for certain combinations of material constant.
Moreover, the force on the disclination dipole is strongly affected
by the position of the disclination dipole and the thickness of
annular inclusion. The repulsion force incerases (or the attraction
force reduces) with the increase of the thickness of the annular
inclusion. An appropriate critical value of the thickness of the
annular inclusion may be found to change the direction of the force
on the disclination dipole. The present solutions include previous
results as special cases.

This paper implements the study on the Dose Rate Upset effect of
PDSOI SRAM (Partially Depleted Silicon-On-Insulator Static Random
Access Memory) with the Qiangguang-I accelerator in Northwest
Institute of Nuclear Technology. The SRAM (Static Random Access
Memory) chips are developed by the Institute of Microelectronics of
Chinese Academy of Sciences. It uses the full address test mode to
determine the upset mechanisms. Specified address test is taken in
the same time. The test results indicate that the upset threshold of
the PDSOI SRAM is about 1x10^{8}Gy(Si)/s. However, there
are few bits upset when the dose rate reaches up to
1.58x10^{9}Gy(Si)/s. The SRAM circuit can still work after the
high level γ ray pulse. Finally, the upset mechanism is
determined to be the rail span collapse by comparing the critical
charge with the collected charge after γ ray pulse. The
physical locations of upset cells are plotted in the layout of the
SRAM to investigate the layout defect. Then, some layout
optimizations have been taken to improve the dose rate hardened
performance of the PDSOI SRAM.

With a memory function approach, this paper investigates the
electronic mobility parallel to the interface in a ZnSe/Zn_{1－x}d_{x} Se strained heterojunction under hydrostatic pressure by
considering the intersubband and intrasubband scattering from the
optical phonon modes. A triangular potential approximation is
adopted to simplify the potential of the conduction band bending in
the channel side and the electronic penetrating into the barrier is
considered by a finite interface potential in the adopted model. The
numerical results with and without strain effect are compared and
analyzed. Meanwhile, the properties of electronic mobility under
pressure versus temperature, Cd concentration and electronic density
are also given and discussed, respectively. It shows that the strain
effect lowers the mobility of electrons while the hydrostatic
pressure effect is more obvious to decrease the mobility. The
contribution induced by the longitudinal optical phonons in the
channel side is dominant to decide the mobility. Compared with the
intrasubband scattering it finds that the effect of intersubband
scattering is also important for the studied material.

This paper studies a discrete one-dimensional monatomic
Klein--Gordon chain with only quartic nearest-neighbor interactions,
in which the compact-like discrete breathers can be explicitly
constructed by an exact separation of their time and space
dependence. Introducing the trying method, it proves that
compact-like discrete breathers exist in this nonlinear system. It
also discusses the linear stability of the compact-like discrete
breathers, when the coefficient (β) of quartic on-site
potential and the coupling constant (K_{4}) of quartic interactive
potential satisfy the given conditions, they are linearly stable.

This paper derives the expressions for the ordering degree and the
modulation factor of A and B atoms in A_{x}B_{1-x}C
epilayers of ternary III--V semiconductor alloys. Using these
expressions, it identifies quantitatively the alternating
atom-enhanced planes, compositional modulations, atomic ordering
degree on the group-III sublattices and the fine structure of NMR
spectra.

CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES

A new self-heating effect model for 4H-SiC MESFETs is proposed based
on a combination of an analytical and a computer aided design (CAD)
oriented drain current model. The circuit oriented expressions of
4H-SiC low-field electron mobility and in-complete ionization rate,
which are related to temperature, are presented in this model, which
are used to estimate the self-heating effect of 4H-SiC MESFETs. The
verification of the present model is made, and the good agreement
between simulated results and measured data of DC I-V curves with
the self-heating effect is obtained.

The scattering matrix approach between the clean and dirty limits is
developed for the study of tunneling spectra in a ferromagnetic film
in proximity to a superconductor. The minigap and the damped
oscillation from ``0" to ``π" state in tunneling conductance are
attributed to the phase coherence of the electrons and the
corresponding Andreev-reflected holes in the ferromagnetic film. The
calculated results provide a reasonable explanation for the behavior
observed in recent experiments.

This paper analyses the reverse recovery characteristics and
mechanism of SiGeC p-i-n diodes. Based on the integrated systems
engineering (ISE) data, the critical physical models of SiGeC diodes
are proposed. Based on heterojunction band gap engineering, the
softness factor increases over six times, reverse recovery time is
over 30% short and there is a 20% decrease in peak reverse
recovery current for SiGeC diodes with 20% of germanium and
0.5% of carbon, compared to Si diodes. Those advantages of SiGeC
p-i-n diodes are more obvious at high temperature. Compared to
lifetime control, SiGeC technique is more suitable for improving
diode properties and the tradeoff between reverse recovery time and
forward voltage drop can be easily achieved in SiGeC diodes.
Furthermore, the high thermal-stability of SiGeC diodes reduces the
costs of further process steps and offers more freedoms to device
design.

This paper investigates the behavior of a pair of electron and hole
in semiconductor superlattice under an external electric field with
the consideration of Coulomb interaction. By numerically calculating
the corresponding probability in the nearest neighbor tight binding
approximation, we find that the single electron (or the hole) can
not be dynamically localized due to the Coulomb interaction, while
the dynamic localization of exciton (the pair of the electron and
hole) still exists. Moreover we find that with the increase of the
intensity of electric field, the exciton can be dynamically
localized more completely.

This paper studies the dependence of I-V characteristics on
quantum well widths in AlAs/In_{0.53}Ga_{0.47}As and
AlAs/In_{0.53}Ga_{0.47}As/InAs resonant tunneling structures
grown on InP substrates. It shows that the peak and the valley
current density in the negative differential resistance region are
closely related with quantum well width. The measured peak current
density, valley current densities and peak-to-valley current ratio
of resonant tunneling diodes are continually decreasing with
increasing well width.

This paper reports that (Ga, Mn)N is prepared using implantation of
3at.% Mn Ions into undoped GaN. Structural characterization of
the crystals was performed using x-ray diffraction(XRD). Detailed
XRD measurements have revealed the characteristic of Mn-Ion
implanted GaN with a small contribution of other compounds. With
Raman spectroscopy measurements, the spectra corresponding to the
intrinsic GaN layers demonstrate three Raman active excitations at
747, 733 and 566\,cm^{-1} identified as E_{-1}(LO),
$A_{1}(LO) and E_{2}^{H}, respectively. The Mn-doped GaN layers
exhibit additional excitations at 182, 288, 650--725, 363,
506cm^{-1} and the vicinity of $E_{2}^{H} mode. The modes
observed at 182, 288, 650--725\,cm^{-1} are assigned to
macroscopic disorder or vacancy-related defects caused by Mn-ion
implantation. Other new phonon modes are assigned to
Mn_{x}-N_{y}, Ga_{x}-Mn_{y} modes and the local vibrational
mode of Mn atoms in the (Ga, Mn)N, which are in fair agreement with
the standard theoretical results.

The magnetic and dielectric properties of Sr-substituted Zn_{2}-Y
hexagonal ferrites (Ba_{2-x}Sr_{x}Zn_{2}Fe_{12}O_{22},
1.0≤x≤1.5) are studied in this paper. Sr substitution will
lead to the variation of cation occupation, which influences both
the magnetic and electric properties. As Sr content x rises from
1.0 to 1.5, magnetic hysteresis loop gets wider gradually and the
permeability drops rapidly due to the transformation from
ferrimagnetic to antiferromagnetic phase. Moreover, permittivity
rises with increasing Sr content. Under a certain external magnetic
field, the phase transition of helical spin structure of
Ba_{0.5}Sr_{1.5}Zn_{2}Fe_{12}O_{22} at about 295K seems
to open a possibility for the room-temperature ferroelectricity
induced by magnetic field. But its low resistivity prevents the
observation of ferroelectric and magnetoelectric properties at
room-temperature.

Ho^{3+}: GdVO_{4} is a new laser material suitable for
high-power laser systems. In this paper we measure the absorption
spectra of Ho^{3+} in the sample Ho^{3+}: GdVO_{4}. The
intensity parameters are calculated by using the Judd---Ofelt
theory. Some predicted spectroscopic parameters, such as the
spontaneous radiative transition rate, branching ratio and
integrated emission cross section are dealt with. And we also
compare the optical parameters with those of other materials. From
these results, it is found that there are many transitions which
have large oscillator strengths and large integrated emission cross
sections. Especially the transitions such as ^{5}F_{4} →
^{5}I_{8}, ^{5}S_{2} → ^{5}I_{8}, ^{5}F_{5} →
^{5}I_{9} and ^{5}I_{7} → ^{5}I_{8} are useful in
solid-state lasers and other fields. Finally, we discuss the
splitting of the energy levels of Ho$^{3+} in the crystal
GdVO_{4} based on the group theory.

8000 CROSSDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY

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