Ion generation from Al-laser-produced plasma

Particle diagnostics of Al-laser-produced plasma based on ion collectors identified three groups of emitted ions. Their velocity distributions were analyzed to obtain the mean ion energy, energy and charge carried by ions, including the angular distributions of these quantities. The electron temperature evaluated from these measurements was compared with X-ray results. A satisfactory agreement between the two sets of data was found. In both the cases the electron temperature grows only very slowly with the incident laser power. Origin of different ion groups is discussed. Iodine photodissociation laser system PERUN was used as a driver.     

Influence of surface functionalization via chemical oxidation on the properties of carbon nanotubes

The surface of carbon nanotubes (CNTs) was functionalized in different chemical oxidants, hydrogen peroxide, mixed concentrated HNO(3)/H(2)SO(4) and acidic KMnO(4) solution. The influences on the properties of CNTs were systematically investigated, such as the structure, the kinds and the contents of the formed surface oxygen-containing functional groups, the pH(PZC) values and the surface hydrophilicity using XRD, HREM, FTIR and chemical titration. The results show that the kinds and the contents of the surface oxygen-containing groups are dependent on the functionalization methods. The formation of the oxygen-containing groups can decrease pH(PZC) values and improve surface hydrophilicity of CNTs. The dispersion of the supported Pd-Pt particles on the functionalized CNTs and their catalytic activity in the profile reaction of naphthalene hydrogenation to tetralin are both promoted due to the presence of these oxygen-containing groups.     

Deterministic solution of the kinetic theory model of colloidal suspensions of structureless particles

A direct modeling of colloidal suspensions consists of calculating trajectories of all suspended objects. Due to the large time computing and the large cost involved in such calculations, we consider in this paper another route. Colloidal suspensions are described on a mesoscopic level by a distribution function whose time evolution is governed by a Fokker–Planck-like equation. The difficulty encountered on this route is the high dimensionality of the space in which the distribution function is defined. A novel strategy is used to solve numerically the Fokker–Planck equation circumventing the curse of dimensionality issue. Rheological and morphological predictions of the model that includes both direct and hydrodynamic interactions are presented in different flows.     

The Effects of Hydrophobicity and Textural Properties on Hexamethyldisiloxane Adsorption in Reduced Graphene Oxide Aerogels

To expand the applications of graphene-based materials to biogas purification, a series of reduced graphene oxide aerogels (rGOAs) were prepared from industrial grade graphene oxide using a simple hydrothermal method. The influences of the hydrothermal preparation temperature on the textural properties, hydrophobicity and physisorption behavior of the rGOAs were investigated using a range of physical and spectroscopic techniques. The results showed that the rGOAs had a macro-porous three-dimensional network structure. Raising the hydrothermal treatment temperature reduced the number of oxygen-containing groups, whereas the specific surface area (S_BET), micropore volume (V_micro) and water contact angle values of the rGOAs all increased. The dynamic adsorption properties of the rGOAs towards hexamethyldisiloxane (L2) increased with increasing hydrothermal treatment temperature and the breakthrough adsorption capacity showed a significant linear association with S_BET, V_micro and contact angle. There was a significant negative association between the breakthrough time and inlet concentration of L2, and the relationship could be reliably predicted with a simple empirical formula. L2 adsorption also increased with decreasing bed temperature. Saturated rGOAs were readily regenerated by a brief heat-treatment at 100 °C. This study has demonstrated the potential of novel rGOA for applications using adsorbents to remove siloxanes from biogas.     

Inequalities for a Simplex and an Interior Point

We establish some inequalities for the inradius, circumradius and distances between an interior point and facets of an n-simplex, and prove a recursion inequality for the radii of the circumscribed spheres of an n-simplex and its facets.     

RuCl3 anchored onto post-synthetic modification MIL-101(Cr)-NH2 as heterogeneous catalyst for hydrogenation of CO2 to formic acid

A series of efficient ruthenium chloride (RuCl_3)-anchored MOF catalysts,such as RuCl_3@MIL-101 (Cr)-Sal,and RuCl_3@MIL-101 (Cr)-DPPB, have been successfully synthesized by post-synthetic modification (PSM)of the terminal amino of MIL-101(Cr)-NH_2 with salicylaldehyde, 2-diphenylphosphinobenzaldehyde (DPPBde) and anchoring of Ru (Ⅲ) ions. The stronger coordination electron donor interaction between Ru (Ⅲ) ions and chelating groups in the RuCl_3@MIL-101 (Cr)-DPPB enhances its catalytic performance for CO_2 hydrogenation to formic acid. The turnover number (TON) of formic acid was up to 831 in reaction time of 2 h with dimethyl sulfoxide (DMSO) and water (H_2O) as mixed solvent, trimethylamine (Et_3N) as organic base, and PPh_3 as electronic additive.     

利用杨辉三角形对称性推导高阶运动微分方程

利用Mathematica数学软件计算函数r=r(q(t),t)各变量之间偏导和高阶导数的关系，发现具有杨辉三角形对称性.结合杨辉三角形的对称性规律和牛顿第二定律推导出了高阶运动微分方程，并讨论了理想约束系统下的高阶运动微分方程. 关键词： 杨辉三角形 牛顿第二定律 高阶运动微分方程 高阶力变率 高阶速度能量 理想约束     

Interaction between two folded solitary waves for a modified Broer--Kaup system

By means of a Painlevé-Baicklund transformation and a multi-linear separation-of-variable approach, abundant localized coherent excitations of a modified Broer-Kaup system are derived. There appear possible phase shifts for the interactions of the （2＋1）-dimensional novel localized structures, which are discussed in this paper.     

ON THE HEISENBERC PICTURE IN QUANTUM ELECTRODYNAMICS

The form of quantum theory of reaiation introdnced by Heiaonbarg is diarnaaed from the point of view of the transformation theory of quantum electrodynamics.A general investigation of the connection between Heisenberg's method and Dirac'smethod of variation of parameters is given.The exetension of Heisenberg's methodto eigenvalue problems.which was first carried out by Weissklpf for the self energyof the electron.is presented in such a way as to show more clearly its quantummechanical interpretation.Ageneral proof of the equivalence of We jsskopf's me-tbod and the method of the perturbation theory of stationary stntes in quantumicechanics is given.     

A Class of Two-mode Nonclassical State via Generalize Super Positions of Two-mode Coherent States

A new method is introduced to generate a elliptical hollow beam inside a cavity. Using a matrix eigenvalue method, the laser resonator with optical diffraction elements is theoretically analyzed and simulated. A elliptical hollow beam of good quality is realized experimentally. The interaction between linearly polarized elliptical hollow beam and a two-level atom is investigated theoretically. Although the linearly polarized elliptical hollow beam does not carry angular momentum, it can produce very high torque. The atoms initially at rest and located at off-beam- axis positions will rotate under the drive of the torque of the beam. The atomic motion trajectory in the field of elliptical hollow beam has been demonstrated. The study shows that the elliptical hollow beam might be a useful tool in the study of vortex property of Bose-Einstein condensate or ultra cold atom media.