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Supplemental material, Supplementary_Material_xyz386656d9e5cda for Genetic Diversity and Prediction Analysis of Small Isolated Giant Panda Populations After Release of Individuals by Qin-Long Dai, Jian-Wei Li, Yi Yang, Min Li, Kan Zhang, Liu-Yang He, Jun Zhang, Bo Tang, Hui-Ping Liu, Yu-Xia Li, Li-Feng Zhu, Zhi-Song Yang and Qiang Dai in Evolutionary Bioinformatics

The ion-adsorption type rare earths ore contains natural U, 232Th and 226Ra. The production of this kind of rare earth concentrate will produce a lot of waste residue and wastewater. It may cause the radioactive pollution and the wastage of radioactive resources. In this paper, a quantitative analysis on the migration and enrichment of natural radionuclides in the extraction process of the ion-adsorption type rare earths ore was developed. The column leaching, impurity removal, precipitation and roasting process were carried out according to the actual extraction process conditions. The related results about RE and Al did accord with the actual production index. For natural radionuclides, most of the radionuclides in the raw ore were retained in the tailings, and only 3.31% natural U, 0.08% 232Th and 0.62% 226Ra migrated into leaching liquor because the partial release of the exchangeable phase and carbonates phase. The radionuclides in the leaching liquor were finally distributed in the impurity slay (about 0.30% natural U, 0.057% 232Th and 0.016% 226Ra), the precipitated liquor (about 1.89% natural U, 0.012% 232Th and 0.59% 226Ra) and the rare earth concertrate (about 1.03% natural U, 0.009% 232Th and 0.019% 226Ra). Moreover, the radionuclides contents in impurities slag and rare earth concentrate were greatly improved than it in the raw ore, being 79.18 mg·kg− 1 natural U, 122.59 mg·kg− 1 232Th, 1.83 × 10− 6 mg·kg− 1 226Ra in impurities slag and 284.07 mg·kg− 1 natural U, 19.95 mg·kg− 1 232Th, 2.31 × 10− 6 mg·kg− 1 226Ra in rare earth concentrate. These part of the radionuclides might could be further enriched by optimum solubilizing, and then recycled by extraction in an economic way. What's more, the radioactive specific activities in the different types of samples were much lower than the specific activities threshold of radioactive waste, and would have little harm to the human body. The research of the migration and enrichment of natural radionuclides in the extraction process had provided accurate and reliable data support for the radioactive pollution prevention and the recovery of radionuclides.

Many previous researches on the plasma sheath were based on the fact that the electrons satisfy the classical Maxwell velocity distribution function, while the particles in the plasma have long-range electromagnetic interactions. It is more appropriate to use the non-extensive distribution proposed by Tsallis to describe the electrons. In this paper, a collisional magnetized plasma sheath model with non-extensive distribution of electrons is established. Bohm criterion is derived theoretically. With the ion drift motion in the plasma pre-sheath region taken into consideration, the ion Mach number is only related to the angle of the magnetic field, the collision parameters, the electric field at the sheath edge, and non-extensive parameter \begin{document}$ q $\end{document}. The influence of parameter \begin{document}$ q $\end{document} on the criterion is discussed in this paper. The lower limit of the ion Mach number changes with the value of parameter \begin{document}$ q $\end{document}. The lower limit of the ion Mach number increases for \begin{document}$ q < 1 $\end{document}. And the lower limit of the ion Mach number decreases for \begin{document}$ q>1 $\end{document}. With the increase of \begin{document}$ q $\end{document}, the number of electrons with lower speed increases, ions need less kinetic energy to enter into the sheath and thus enter into the sheath more easily. Through numerical simulation, it is found that compared with the structure of the plasma magnetized sheath with Maxwell distribution (\begin{document}$ q=1 $\end{document}), the structure of the plasma magnetized sheath with super-extensive distribution (\begin{document}$ q < 1 $\end{document}) and that with sub-extensive (\begin{document}$ q>1 $\end{document}) are different, including the distribution of the space potential, the ion density, the electron density, and the space charge density. When \begin{document}$ q < 1 $\end{document}, the space potential, the electron density and the ion density fall more slowly, and the peak of the space charge density curve is closer to the wall. When \begin{document}$ q>1 $\end{document}, the space potential and the ion electron density fall faster, especially the electron density drops to zero faster, and the peak of the space charge density curve is far away from the wall. The simulation results show that the non-extensive parameter \begin{document}$ q $\end{document} has a significant influence on the structure of collisional plasma magnetized sheath. The influence of the collision on the magnetized plasma sheath with non-extensive distribution is similar to that with the Maxwell distribution. These conclusions may be useful in solving the problems of plasma boundary.

The sheath criterion for an electronegative plasma composed of hot electrons, hot negative ions and cold positive ions in an oblique magnetic field is investigated. We discuss the effects of negative ions and external magnetic field on the sheath criterion. We find that the ion Mach number is of relatively low value because of Coulomb attraction between positive and negative ions. Also the ion Mach number depends on the magnitude and the angle of the magnetic field as well as the initial velocity of ion flow.

A generalized finite element formulation is proposed for the study of the spin-dependent ballistic transport of electron through the two-dimensional quantum structures with Rashba spin-orbit interactions (SOI). The transmission coefficient, conductance, the total and local polarization are numerically calculated and discussed as the Rashba coefficient, the geometric sizes, and incident energy are changed in the T-shaped devices. Some interesting features are found in the proper parameter regime. The polarization has an enhancement as the Rashba coefficient becomes stronger. The polarization valley is rigid in the regime of the conductance plateaus since the local interference among the polarized multi-wave modes. The Rashba interactions coupling to geometry in sizes could form the structure-induced Fano–Rashba resonance. In the wider stub, the localized spin lattice of electron could be produced. The conductance plateaus correspond to weak polarizations. Strong polarizations appear when the stub sizes, incident energy, and the Rashba coupling coefficient are matched. The resonances are formed in a wide Fermi energy segment easily.

Bombarded by slow highly charged ion (SHCI), particles including ions and atoms of metal are excited and ejected from the sample. Optical emission can be observed for the radiative de-excitation of some excited atomic particles. The important information about particle ejection and incident ion neutralization, as well as the nature, the kinetic energy, and the number of the sputtered excited particles can be obtained by studying the optical emission process. The optical emission from the the collisions between slow (V~0.38 VBohr) highly charged Xeq+ (4 q 20) ions and high purity Ni (99.995%) surface is studied. The experiment is carried out at the 320 kV for multi-discipline research with HCIs in the Institute of Modern Physics, Chinese Academy of Sciences. The spectral lines are analyzed by using an Sp-2558 spectrometer equipped with a pattern of 1200 groves/mm blazed at 500 nm and an R955 photomultiplier tube at the exit slit. The target beam current corresponding to the dwell time is recorded, which can be translated into the incident ion current. Based on the formula of Y=N/(t/Ceq), the spectral line intensity is normalized. The normalized spectrum can be obtained from the interaction of 0.38VBohr Xe20+ ions with Ni surface in a wavelength range of 400-510 nm. The species at excited state can be identified by comparing the wavelengths of spectral lines with those in the standard spectroscopic table. Most of the observed spectral lines are identified as being from the electron transitions of Ni I 3d9(2D)4p-3d9(2D5/2)4d, Ni I 3d8(3F)4s4p(3P)-3d84s(4F)5s and Ni Ⅱ 3p63d9-3p63d8(3P)4s, as well as Xe I 5p5(2P3/2)6s-5p5(2P3/2)8p, Xe Ⅱ 5p4(3P2)6p-5p4(3P2)6d and Xe Ⅲ 5s25p3(2D)6s-5s25p3(2D)6p. Compared with the single charged ion, some neutralized incident ions yield Xe I, Xe Ⅱ, Xe Ⅲ spectral lines. The photon yields of spectral lines, such as Xe Ⅱ 410.419, Xe Ⅲ 430.444, Xe Ⅱ 434.200, Xe Ⅱ 486.254, Ni I 498.245, Ni I 501.697, Ni I 503.502, Ni I 505.061 and Ni I 508.293 nm, are presented each as a function of charge state of incident ion. The results show that the photon yield increases with the increase of the charge state, which is consistent with the potential energy of the incident ion. The potential energy is the driving force for photon emission of excited Ni atom. The neutralization of Xeq+ is in good agreement with that indicated by the classical over-the-barrier model.

First-principles calculations have been performed for the study of the electronic hand structure and ferromagnetic properties of double perovskite Ca2CrSbO6. The density of states, total energy, spin magnetic moment, and charge density were calculated and analyzed in details. It is found that Ca2CrSbO6 has a stable ferromagnetic ground state and the spin magnetic moment per molecule is about 2.99μB. The chromium contributes the most in the total magnetic moments. The results indicate that Ca2CrSbO6 is half-metallic.

With the help of the first-principles full potential linearized augmented plane wave method, absorption coecients, reflectivity, dielectric behavior and electronic properties, including electronic energy bands, density of states and charge density distributions, are studied for the tetragonal and cubic CaTiO3. By considering the thermal expansion eects, an approximate method is proposed for the study of the stability of ground state and a tendency of phase transition, based on the minimum free energy principle. Subsequently, numerical calculations are carried out by using the first-principles perturbation method. We demonstrate that the high-temperature phase is cubic. It is shown that optical spectra in tetragonal phase exhibit single-peak feature and dier from multi-peak character in cubic. We find that strong orbital hybridization results in the co-valent bonds between Ti 3d and O 2p electrons and forms two-type dipoles (Ti-O1 and Ti-O2) in tetragonal, while the Ti-O dipoles are identical in cubic. It is argued that crystal structure determines the dipole distributions and leads to some electron states among which the dipole-dipole transition forbidden is a key, causing such anomalous optical phenomena with the insulator characteristics. The predicted charge density distribution and the tendency of phase transition from tetragonal to cubic are in good agreement with experimental observations.

In the framework of Green's function theory out of equilibrium, a Landauer–Buttiker (LB) formula for thermal conductance is derived. A simplified model for describing extremely cold dielectric chains is proposed for the first time. Further we apply the present LB formula for studying thermal conductance at low-lying modes, emerging in dielectric atom chains. We find that quantum thermal conductance undergoes an anomalous transition due to new quasiparticle excitations, resulting from nonlinear atom–atom interactions. This theoretical prediction is in excellent agreement with a high-accuracy measurement to thermal conductance quantum.

With the help of an improvement Monte Carlo method, the Berezinskii–Kosterlitz–Thouless phase transition arising in two-dimensional planar rotator model with weak Dzyaloshinsky–Moriya (DM) interaction is investigated. The effects of the DM interaction on specific heat, susceptibility, and magnetization are simulated. The critical temperature of transitions is determined by the so-called Binder cumulant and the susceptibility of finite-size scaling. We find that the chiral Z2 symmetry reduced by the DM interactions plays an important role in a two-dimensional XY spin system, typically, the critical temperature is sensitive to weak DM spin couplings.

Employing the recoil ion momentum spectroscopy we investigate the collision between He2+ and argon atoms. By measuring the recoil longitudinal momentum the energy losses of projectile are deduced for capture reaction channels. It is found that in most cases for single- and double-electron capture, the inner electron in the target atom is removed, the recoil ion is in singly or multiply excited states (hollow ion is formed), which indicates that electron correlation plays an important role in the process. The captured electrons prefer the ground states of the projectile. It is experimentally demonstrated that the average energy losses are directly related to charge transfer and electronic configuration

State-selective single electron capture cross sections are measured by recoil ion momentum spectroscopy technique for He2+ on He at 30 keV incident energy. The cross sections for capture into ground and excited states are obtained and compared to classical model calculations as well as to the quantum mechanical calculations. The experimental results are in good agreement with quantum mechanical results.

A new combination Monte Carlo (MC) technique of the classical Metropolis algorithm and the Swendsen–Wang cluster algorithm is proposed. Upon application of the MC technique, the thermodynamic properties of a generalized two-dimensional XY model with chiral Dzyaloshinski–Moriya (DM) interactions are simulated for various DM interactions. The specific heat, order parameter and the integrated correlation time are simulated. We find that there exists a high-temperature Kosterlitz–Thouless-type phase transition related to strong DM spin chiralities. As the DM strength increases the critical temperature of the Kosterlitz–Thouless phase transition increases. It is shown that the combination algorithm is faster than the Metropolis algorithms.

Spectra of carbon-, boron-, beryllium-, lithium-, helium-, and hydrogen-like sulfur ions were obtained and studied for the wavelengths below 200 A and the energy of 80 MeV by using beam-foil method. Thirty-five lines have been identified, in which 15 lines are newly accurately measured. The spectra were analysed based on the theoretical results and other experimental data.

Heat conductivity is studied by direct numerical simulations in a two-dimensional model with chiral Dzyaloshinskii–Moriya (DM) spin superexchange interactions for various DM strengths and finite sizes. We find that when temperature is not too low, the thermal conductivity can be well described in the semi-classical spin wave picture, and connections of thermal conductivity with the specific heat and the dynamic relaxation time are verified to be suitable. In particular, the transition arising in Sr14−xCaxCu24O41 is related to a magnetic spin glass and qualitatively understood as a kind of Kosterlitz–Thouless transitions. It is shown that the critical temperature is linearly dependent on the spin–spin interactions for the relevant strong DM strength.

The cross section ratios of the double, triple and quadruplicate ionization to the single ionization of argon by 1.5-7.5 MeV partially stripped carbon ions are measured by using time-of-flight technique. The Auger transition and the charge exchange process in the multiple ionization of argon are studied. The ratios of cross sections of the direct multiple ionization to those of the direct single ionization are obtained by subtracting the parts of the Auger transition and the charge exchange process from the measured data. It is found that the cross section ratios of the direct multiple ionization to those of the direct single ionization are in good agreement with the predicted multi-step (ν/qeff)-2n+2 law.

The structure of an electronegative plasma sheath in an oblique magnetic field is investigated. Moreover, the collisions between positive ions and neutral particles are taken into account. It is assumed that the system consists of hot electrons, hot negative ions, and cold positive ions. Also the negative ions and the electrons are assumed to be described by the Boltzmann distributions of their own temperatures, and the accelerated positive ions are treated by the continuity and momentum balance equations through the sheath region. In addition, it is assumed that the collision cross section has a power law dependence on the positive velocity. After theoretical derivation, an exact expression of sheath criterion is obtained. The numerical simulation results include the density distributions of the positive ions for different invariable ion Mach numbers satisfying Bohm criterion, and the comparison of net space charge distribution between variable and invariable ion Mach numbers. Furthermore, three kinds of charged particle densities, the net space charges, and the spatial electric potentials in the sheath are studied numerically for different collision parameters under the condition of the fixed ion Mach number. The results show that the ion Mach number has not only the lower limit but also the upper limit. The ion Mach number affects the sheath structure by influencing the distribution of the positive ion density, and different conclusions can be obtained because ion Mach number is adopted as variable or invariable value when discussing the effects of the other variables which can result in a variety of the ion Mach numbers on the sheath formation. The reason is that the actual sheath structure modification brought on by the variation of a parameter can be divided into two parts. One is the sheath formation change caused directly by the variation of the parameter, and the other is the sheath formation change caused by the Bohm criterion modification which the variation of the parameter results in. Therefore, an identical ion Mach number should be adopted when studying the direct effects of a parameter variety on plasma sheath structure. In addition, it is concluded that the collisions between positive ions and neutral particles make positive ion density curve higher and electron density curve lower than the case without collisions. Negative ion density does not change significantly no matter whether there exists collision. Besides, there is a peak in the profile of the net space charge while in the presence of ion-neutral collision, and the net space charge peak moves toward the sheath edge. The spatial potential increases and the sheath thickness decreases on account of the presence of the collisions between ions and neutral particles.

The shortage and demand for the communication of multi-robot system are concisely analyzed and the design of the multi-robot communication system on the TCP/IP and the thought of the program are proposed. Based on the multi-robot system which is made up of the MOTOMAN-HP3 serial robot and NPT800 parallel robot, the MOTOMAN-HP3 serial robot ontology communication, NPT800 parallel robot of motion control and communication between two robots are introduced respectively. In the end, the mutual communication can be accomplished by two robots and the robot position and status information can be transported with programming of the win socket.

Bovine lactoferrin (Lf) is an 80 kDa iron-binding protein of the transferrin family that possesses many biological activities. It is now recognized that this glycoprotein is a key element in the mammalian immune system, playing an important role in host defence against infection and excessive inflammation. The present study was designed to determine in vivo efficacy of Lf for enhancing immune modulating properties in BALB/c mice. Mice were administered to Lf by gavage once daily for 14 consecutive days of different dose. The result demonstrates that Lf could enhance the immunity level in the respect of immune organ, lymphocyte proliferation, macrophage phagocytosis and antibody production.

Consumption of some species and strains of lactic acid bacteria (LAB) has been shown to enhance immunity in humans. In this study, the effect of dietary supplementation with Lactobacillus rhamnosus TUST006, a newly characterized LAB strain, on enhancing the function of immunological effecter cells in BALB/C mice was investigated. In order to find out which composition of fermentation liquor play important role in enhancing the function of immune regulation, the mice were divided into six groups. Then the subjects were orally administrated to BALB/c mice for 4 weeks by the method of priming. The results showed as follows: all groups of different processed fermentation liquid could enhance the immunity level; the living bacterium one among the test groups presented the significant immunity enhancement. The immune active ingredients of L.rhamnosus were not only living bacterium but also metabolites.

Fat consumption by western populations has been shown to be associated with an increased risk of obesity, coronary heart disease and so on. Hence, fat replacer had been widely used in cheese to satisfy the needs of people's health and improve flavor early. In this paper, low-fat Mozzarella cheeses were made from skim milk and corn oil W1/O/W2 multiple emulsions, which deviated greatly from previous fat substitutes, in that they exhibited very small inner water droplets encased in much larger oil droplets. Both, they might modify the rheological and textural properties of the cheese by their interactions with milk proteins. In our research, five low-fat cheesees(LC) were made from skim milk added with 27 g of multiple emulsions L-1, which was stabilized by amidated low-methoxyl pectin (LMP), carboxymet hylcellulose (CMC), Gum Arabic (GA), and blends of GA-CMC or GA-LMP, while the reduced fat cheese (1.8% CMC) was prepared from milk containing 18 g of milk-fat L-1 and 9 g of multiple emulsions L-1 (CMC). The results indicated that the fat in total solids and cheese yield of cheese decreased significantly with the decrease of the content of cheese milk, but the moisture and total nitrogen values increased significantly. Because LCLMP contributed to the formation of network structure of the crosslinking reaction by the calcium, it was of most hardness. Similar springness was showed in low-fat cheeses, but higher than the control. All the cheeses made from multiple emulsions improved stretchability greatly, because they enhanced the role of cross-linking of proteins and made cheese stickier to bear the external force. All of the low-fat cheeses showed differences in microstructure.

Yogurt Drinking was a production of Lactic acid, was rich in various nutrients. In this paper, Yogurt Drinking was directly made from fermented milk, in which Lactobacillus casei and Lactobacillus helveticus were combined to encourage to the formation of flavor compounds. In this research, glucose in fermented milk was to speed up the browning. The optimum conditions of fermented milk are as follows: the ratio of L.c to L.h was 2:1, fermentation temperature was 30°C and inoculum sizeis was 3%(w/w). The optimum conditions of yogurt drinking were as follows: fermented milk 32%(w/w), sugar 6.4%(w/w), acidity of fermented milk was 200°T. The main components of the final production were determined as total solids 12.5%, protein 1.29%, the concentration of viable counts was 2.8×108 cfu/mL. Due to the lowest sedimentation rate, pectin was the the best stabilizer, moreover, the production made from pectin, was of uniform and exquisite texture and diverged special aroma. Suitable dosage was 0.26%(w/w). Acidity was an important factor of flavor in milk beverage. In our research, acidity from starter culture was distinct from traditional method of adding sour agent in the later period. This made up the defects of covering up the pure flavor by additives.

In the fields of global environment change and sustainable development, analysis of land uses and landscape patterns plays a very important part. Using the TM remote sensing images of Miyun County in the years of 1997, 2001 and 2007, this paper made them interpreted and classified. This paper analyzed the changes of land uses and landscape patterns in Miyun County according to the land use type transfer matrix and landscape pattern indices, and made an assessment of the ecological environment by using ecosystem service value per unit area of different terrestrial ecosystem types in China. The result showed that the main land use types of the study area are forest land, grassland and agricultural land, and grassland decreased and construction land increased under human influences. The diversity of the area was low and the increment of the degree of fragmentation was relatively significant. The overall ecological value of the area lay in the middle or high levels and didn't change much during the study periods. The temporal and spatial variations of ecological values demonstrated the influences of land use and landscape pattern changes and structures towards the ecological environment.

Podoplanin is a mucin-like glycoprotein expressed in the lymphatic endothelium. It has been suggested to play a role in lymphangiogenesis, since podoplanin deficient mice were found to have dilated malfunctioning lymphatic vessels and lymphedema. High podoplanin expression in tumor cells was found to correlate with lymph node metastasis and poor clinical outcome in patients with oral squamous cell carcinoma (SCC). However, the prognostic significance of podoplanin expression in esophageal SCC remains unexplored. Herein, we studied podoplanin expression in 59 patients who underwent surgical resection of esophageal SCC, with 43 of them preceded by preoperative concurrent chemoradiotherapy (CCRT). We found that high podoplanin expression strongly correlated with clinical nodal metastasis (cN1; p=0.0063), which was associated with short survival (p=0.012). However, there was no direct association between high podoplanin expression and short survival. We also found that lymphatic vessel invasion in the resected esophagus was strongly associated with pathological nodal metastasis (pN1; p=0.00092). Our results suggest that podoplanin could also play a role in tumor aggressiveness in esophageal SCC, as well as in oral SCC.

The Bohm criterion for a collisinal electronegative plasma sheath in an oblique magnetic field is investigated with a fluid model. The effects of negative ions and magnetic field on the Bohm criterion are discussed. It is shown that the parameters of the negative ions affect only the lower limit for Bohm criterion, and the external magnetic field can affect the whole range of the ion Mach number values.

This paper studies the projectile electron loss cross sections of C3+ colliding with atomic hydrogen in the frame work of extended over-barrier model at intermediate velocities (25 keV/u–600 keV/u). The electron loss is calculated in terms of the interaction between the screened target nucleus and the active projectile electron and of the interaction between projectile electron and target electron. Compared with the convergent close-coupling calculations, screening and anti-screening calculations, this model satisfactorily reproduces the experimentally obtained energy dependence of the electron-impact ionisation cross sections and the single electron loss cross sections over the energy range investigated here.

In this paper a projectile ion-recoil ion coincidence technique is used to investigate the transfer ionization processes in collisions of 0.22–6.30 MeV Cq+ ions and 0.25–6.35 MeV Oq+ ions (q = 1, 2, 3, 4) with the He atom separately. The cross section ratio f of transfer ionization to single electron transfer is measured, and the dependence of f on both charge state q and energy E of the projectiles is investigated. The electron-structure and the mechanisms leading to transfer ionization affect the dependence of f on q and E. Our measurements, along with other data published previously, suggest a similar dependence of f on charge state and energy of projectile for partially stripped ions over a large energy range. The maximum value of f is approximately 0.17q0.60; the energy corresponding to maximum f is about 160q0.60 keV/u.

Laser-induced breakdown spectroscopy (LIBS) as a powerful analytical technique is applied to analyze trace-elements in fresh plant samples. We investigate the LIBS spectra of fresh holly leaves and observe more than 430 lines emitted from 25 elements and molecules in the region 230?438 nm. The influence of laser wavelength on LIBS applied to semi-quantitative analysis of trace-element contents in plant samples is studied. The results show that the UV laser has lower relative standard deviations and better repeatability for semi-quantitative analysis of trace-element contents in plant samples. This work may be helpful for improving the quantitative analysis power of LIBS applied to plant samples.

The processes of transfer ionization in He2+-He collisions at energies ranging from 20 to 40 keV have been studied experimentally by means of cold target recoil ions momentum spectroscopy. From the longitudinal momentum spectra of recoil ions, different mechanisms of transfer ionization have been obtained. The results show that one of the electrons of helium atom being captured into the ground state of projectile ion He2+ and the other one emitted to the continuum state of projectile or target are the dominant mechanisms of transfer ionization. The autoionization cross section of projectile after two-electron capture into a double excited state is small. Transfer ionization for one target electron capture into ground state and the other one into the continuum of projectile mainly occurs at large impact parameter collisions.

The velocity distribution of emission electrons in the transfer ionization process of 70keV He2+ colliding on He has been studied with a reaction microscope. These distributions show that the electrons lie mainly in the scattering plane which are observed to be emitted preferentially in the forward direction, lying between 0 and projectile velocity Vp. The distributions also display a typical two-fingered structure with a local minimum on internuclear axis. This characteristic can be qualitatively explained as being due to the interference between σ amplitude and π amplitude of electrons final wavefunction. It depends also on the impact parameters; the π amplitude contribution is dominant at small impact parameters, which leads to a symmetric velocity distribution around the internuclear axis. However, at large impact parameters the σ amplitude contribution increases relatively obviously, resulting in an asymmetric electrons velocity distribution around the internuclear axis.

We solve the two-dimensional strongly nonlocal nonlinear Schrdinger equation in polar coordinates. An exact analytical solution of self-similar waves, namely Kummer-Gaussian soliton clusters, is obtained. Numerical simulations confirm the validity of the analytical solutions. It is shown that the nonlocal optical spacial solitons have large phase shift.

A two-fluid model is proposed to describe the collisional radio-frequency plasma sheath in a magnetic field, and the ion energy distribution incident on the radio-frequency sheath biased electrode is numerically investigated. The simulation results reveal that the external magnetic field dominates the ion flux and energy distribution of the sheath. The ion energy can be transferred between the perpendicular direction and parallel direction under the action of magnetic field.

State-selective single electron capture in He2+-He collisions at energies ranging from 20 to 40 keV have been studied experimentally by means of cold target recoil ion momentum spectroscopy. The differential cross sections have been obtained by measuring the longitudinal and transverse momenta of recoil ions. The results show that single electron capture into L shell is the dominant reaction channel, which was qualitatively explained with reaction window theory. The measured state-selective cross sections agree with the semi-classical close-coupling calculations, but have some deviations from the results of photon emission measurement. Total angular differential cross sections show that the single electron capture into ground state mainly contributes at small angles, and the single electron capture into excited states contributes at large angles. The oscillating structures of angular differential cross sections are observed, and can be understood by the interference of molecular orbits during the collision processes. The measured angular differential cross sections are compared with other experiments and the quantum-mechanical calculation.

The structure of plasma sheath in an oblique magnetic field is numerically investigated by using fluid dynamics method. The simulation results reveal that the magnetic field has significant effects on the plasma sheath. Especially, the ion density distribution near the sheath edge changes obviously. Two cases of ion incidence are considered here. The action states of ions are more complicated when the ions enter the sheath with an oblique incidence angle. Under suitable conditions, Lorentz force induces fluctuations in the ion density. Ions could gather in some regions.

In order to expand the solid angle for imaging of electrons in ion-atom collisions, we designed a complex Helmholtz coils composed of four single coils. Theoretical simulations were carried out to optimize the arrangement of the coils. The complex is constructed according to the theoretical analysis, and the magnetic fields were measured for interested regions. The measured results show that the relative uniformity of the magnetic fields is ±0.6%, which satisfies the requirements of collision experiments.

Based on the technique of PIV (particle image velocimetry),We calculated the light intensity of the bubble interface and discovered that the intensities of lighr reflected or refracted twice succeedingly abide by the rules of geometric series, and the light will disappear after reflecting or refracting 4 times by the bubbles. When the angle of incidence of 35° is avoided , the intensity of second refraction out of a bubble is independent of the incident beam width, similar to the case of a narrow light ray falling on the bubble interface. The integral formulas for the intensities of reflection or refraction are given for the planar light beam falling on the bubble interface. The numerical solution of the integral is in agreement with the experiment value.

The emission cross sections and excitation cross sections have been measured in collisions between N4+ ion and Na atoms. The experimental results show that the excitation cross sections of NaI(3p-3s) are vety large, about １０-15ｃｍ2 . The data of cross sections have been given in this paper and reasons for the large excitation cross sections of NaI(3p-3s) have been discussed qualitatively.