Magnetic field effect in photodetachment from negative ion in electric field near metal surface

Based on the closed-orbit theory, the magnetic field effect in the photodetachment of negative ion in the electric field near a metal surface is studied for the first time. The results show that the magnetic field can produce a significant effect on the photodetachment of negative ion near a metal surface. Besides the closed orbits previously found by Duet al. for the H in the electric field near a metal surface （J. Phys. B 43 035002 （2010））, some additional closed orbits are produced due to the effect of magnetic field. For a given ion surface distance and an electric field strength, the cross section depends sensitively on the magnetic field strength. As the magnetic field strength is very small, its influence can be neglected. With the increase of the magnetic field strength, the number of the closed orbits increases greatly and the oscillation in the cross section becomes much more complex. Therefore we can control the photodetachment cross section of the negative ion by changing the magnetic field strength. We hope that our results may guide future experimental studies for the photodetachment process of negative ion in the presence of external fields and surfaces.

INFLUENCE OF EXTERNAL MAGNETIC FIELD ON THE FLOW FIELD IN MOLTEN SEMICONDUCTOR OF CZOCHRALSKI CRYSTAL GROWTH——A NUMERICAL SIMULATION

Numerical results show that an external magnetic field may influence significantly the flow pattern in the molten semiconductor of Czochralski crystal growth. The melt flow could be pronouncedly damped by a magnet. ic field with the intensity of several thousands Gauss, while the temperature field is affected only in a less extent by the magnetic field.

Effects of Magnetic Field on Photodegradation of Methylene Blue over ZnO and TiO2 Powders using UV-LED as a Light Source

The magnetic field effects （MFEs） are studied on photocatalytic degradation of methylene blue （MB） solution using ZnO and TiO2 particles. The UV-VIS-NIR spectrometer is used to monitor the MB concentrations, and the dependence of the reaction rate on the initial dye concentration and settling duration is studied under UV light irradiation. It is found that the MFEs exist on the heterogeneous reaction systems for both ZnO and TiO2 powders and that the extraordinary phenomenon is reproducible. For ZnO powder, the results are in good agreement with the second-order reaction kinetics following the Langmuir-Hinshelwood （L-H） model, while the reaction for TiO2 follows first-order kinetics. It enhances the photodegradation for ZnO, while it reduces or enhances the reaction for TiO2 depending on the initial dye concentrations. The MFEs become small or negligible when the same photodecomposition experiment is carried out after settling the MB solution for more than three hours for both ZnO and TiO2. It is suggested that the key factors of MFEs on photocatalytic degradation is the condition of the MB solution as well as the characteristics of photocatalysts. The alteration of the MFEs ascribed to the solution condition caused by variation of the settling time.

The Effects of Magnetic Fields on Swing Amplifier

The excitation and evolution of magnetohydrodynamic density waves are considered in a differentially rotating thin gaseous disk embedded with both an azimuthal magnetic field and a vertical magnetic field perpendicular to the disk. Our results shows that the effect of isopedic vertical magnetic fields tend to stabilize the fast MHD density waves while slow MHD density waves are not affected by such vertical magnetic fields for either rigid or differential rotation.

The Magnetic Field Effect on the Polymerization of Styrene in Supercritical Carbon Dioxide

Styrene was polymerized in supercritical （sc） CO2 with benzoyl peroxide （BPO） as initiator. It was found that the polymerization was accelerated by the external magnetic field.

Oxygen Incorporation in Czochralski Growth of Silicon under a Horizontal Magnetic Field

A mechanism of oxygen transportation in Czochralski growth of silicon crystals under a horizontal magnetic field (HMCZ) is proposed. Oxygen depleted surface melt, driven to the growth interface by the thermal Marangoni flow, determines oxygen concentration in the grown crystals. Systematic study was carried out to investigate effects of growth parameters on oxygen incorporation into crystals.

In situ FTIR Investigation of Magnetic Field Effect on Heterogeneous Photocatalytic Degradation of Benzene over Pt/TiO_(2)

In situ FTIR spectroscopy was utilized to investigate the magnetic field effect on the heterogeneous photocatalytic degradation of benzene over platinized titania （Pt/TiO2）. The results revealed that the employment of magnetic field may not change the mechanism of photocatalytic degradation of benzene, however, it greatly facilitate the conversion of benzene to phenol and quinone, as well as the transformation from phenol to quinone, resulting in opening the benzene ring easily and promoting the production of CO2.

Effects of Pure Dzyaloshinskii-Moriya Interaction with Magnetic Field on Entanglement in Intrinsic Decoherence

We investigate the effects of pure Dzyaloshinskii Moriya （DM） interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states ｜φ±〉 = （｜00） ± ｜11〉）/√2 and ｜ψ±〉 = （｜01） ±｜10〉）/√2, respectively. It is found that if the system is initially in the state p1（0） = ｜φ＋〉〈φ＋1, the entanglement can obtain its maximum when the DM interaction vector D is in the plane of XOZ and magnetic field B = By with the infinite time t, moreover the entanglement is independent of By and t when By is perpendicular to D. In addition, we obtain similar results when the system is initially in the states p2（0） = ｜φ-〉〈φ-｜ or p3 （0） = ｜ψ＋〉〈ψ＋1. However, we find that if the system is initially in the state P4 （0） = ｜ψ-〉〈ψ-l, the entanglement can obtain its maximum for infinite t, when the DM vector is in the plane ofYOZ, XOZ, or XOY, with the magnetic field parallel to X, Y, or Z axis, respectively. Moreover, when the axial B is perpendicular to D for the initial state p4（O）, the negativity oscillates with time t and reaches a stable value, the larger the value of B is, the greater the stable value is, and the shorter the oscillation time of the negativity is. Thus we can adjust the direction and value of the external magnetic field to obtain the maximal entanglement, and avoid the adverse effects of external environment in some initial state. This is feasible within the cun＇ent experimental technology.

MAGNETIC FIELD EFFECT ON PHOTOPOLYMERIZATION OF STYRENE MICROEMULSION

External magnetic field increases the photo-induced polymerization rate of styrene microemulsion.The type of photoinitiator plays an important role. The photoinitiators, used are dimethoxyphenyl acetophenone(DMPA), 1-hydroxycyclohexyl phenylketone (Irgacure 184) and dimethylhydroxyacetophenone (Darocur 1173). No magnetic effect was observed by using dibenzylketone (DBK) as photoinitiator. The molecular weight of the polymer is slightly affected by magnetic field. The influence of temperature has also been investigated.

Lattice Boltzmann Simulation of Magnetic Field Effect on Electrically Conducting Fluid at Inclined Angles in Rayleigh-Bénard Convection

The magneto-hydrodynamics(MHD)effect is studied at different inclined angles in Rayleigh-Bénard(RB)convection inside a rectangular enclosure using the lattice Boltzmann method(LBM).The enclosure is filled with electrically conducting fluids of different characteristics.These characteristics are defined by Prandtl number,Pr.The considered Pr values for this study are 10 and 70.The influence of other dimensionless parameters Rayleigh numbers Ra=10^(3);10^(4);10^(5);10^(6) and Hartmann numbers Ha=0,10,25,50,100,on fluid flow and heat transfer,are also investigated considering different inclined anglesφof magnetic field by analyzing computed local Nusselt numbers and average Nusselt numbers.The results of the study show the undoubted prediction capability of LBM for the current problem.The simulated results demonstrate that the augmentation in heat transfer is directly related to Ra values,but it is opposite while observing the characteristics of Ha values.However,it is also found thatφhas a significant impact on heat transfer for different fluids.Besides,isotherms are found to be always parallel to the horizontal axis at Ra=10^(3) as conduction overcomes the convection in the heat transfer,but this behaviour is not seen at Ra=10^(4) when Ha>25.Furthermore,at Ra=10^(6),oscillatory instability appears but LBM is still able to provide a complete map of this predicted behavior.An appropriate validation with previous numerical studies demonstrates the accuracy of the present approach.

Laws of Reduction of NO with Carbon Monoxide Using a Magnetic Field Effect

We first received the previously unknown pattern of the magnetic field and relativistic effects on chemical reactions in catalysis for example, reduction NO with monooxide carbon with used magnetic uranium catalysts, which is to reduce the activation energy of the reactants with increasing concentration of magnetic materials and due to the interaction and control of the motion of ions and electrons with atoms and attraction between ions by means of a magnetic field.

Effect of Magnetic Field on the Ionization Potential of the Atoms and Ions

The authors found the effect of magnetic field on the ionization of atoms and ions and shown that the magnetic field affected the rate of ionization and electron emission at angle of 60°, 120°, 240° and 300°. It is shown that the calculation must take into account the ionization potential of the magnetic field.

Combined Effect of Uniaxial Strain and Magnetic Field on the Exciton States in Semiconducting Single-Walled Carbon Nanotubes

The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the excitation energies and absorption spectra of zigzag tubes（11,0） and（10,0） show opposite trends with the strain under the action of the magnetic field. For the（11,0） tube, the excitation energy decreases with the increasing uniaxial strain, with a splitting appearing in the absorption spectra. For the（10,0） tube, the variation trend firstly increases and then decreases, with a reversal point appearing in the absorption spectra. More interesting,at the reversal point the intensity of optical absorption is the largest because of the degeneracy of the two bands nearest to the Fermi Level, which is expected to be observed in the future experiment. The similar variation trend is also exhibited in the binding energy for the two kinds of semiconducting tubes.

Effect of gradient magnetic field on physiochemistry functions of rice seedlings

Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged in eachother south and north pole.The magneticstrength was 0-40 mT.Each four varieties wasput under the magnetic plate 15 cm away,andwent through the magnetic field with the speedof 20 cm/s.The same varieties without thetreatment were used as CK.Both of the seedswere soaked in water for 48 h in room temper-ature,and then sprouted on the porcelain platewith absorbed water paper.When the

Radical involved reactive wetting and retarding mechanism of alumina refractory ceramic by molten slags under weak static magnetic field

High alumina slag will cause severe corrosion at the interface of alumina refractory,and the wetting behavior of slag is a key factor influencing the corrosion resistance of refractory ceramics.The static magnetic field is a promising solution for improvement in the slag resistance of refractory.The wetting of alumina refractory ceramics with different basicities of high alumina slags under a weak static magnetic field was analyzed,given that a weak static magnetic field can affect the corrosion behavior of refractory ceramics.Taking slag S_(3) as an example,when there was an external static magnetic field of 1.0 mT at 1600 ℃,the thickness of calcium aluminate reaction layer at the interface decreased by 36.7%,the denting depth of interface decreased by 35.6%,and the apparent wetting angle increased by 20%.The living radicals and their formation path in oxide melts were verified by first-principles calculation combined with electron paramagnetic resonance spectroscopy analysis.The influence of the flux density of a weak static magnetic field on the wetting behavior of slags was also explored.The contact angle of the slags increased owing to the inhibitory effect of magnetic field on the radicalinvolved reaction at the interface of the slag and the alumina refractory ceramic.The relationships between the magnetic flux density,diffusion coefficient,slag microstructure(hyperfine coupling constant),and contact angle were established.This provides a theoretical basis for the field control of radical involved reactive wetting between inorganic oxide slags and solid oxide ceramics.

Dynamics of A Rotor Supported on Magnet-Rheological Fluid Squeeze Film Damper

Using special characteristics of magneto-rheological (MR) fluid with rapid, reversible and dramatic change in its viscosity by an external magnetic field, a novel controllable magneto-rheological fluid squeeze film damper is presented in this paper. After analyzing the effects of the MR fluid, the externally applied magnetic flux density and the radial clearance of the damper on the behavior of a flexible rotor supported on the MR fluid squeeze film damper in the non-rotating state, an experimental study is carried out on the controllability and effectiveness of the MR fluid squeeze film damper on the rotor vibration in the rotating state. The existing problems in the MR fluid squeeze film damper, such as unbalanced magnetic pull force, and MR fluid sediment, which may result in the failure of the MR fluid squeeze film damper application, are also discussed. It is shown that not only can the dynamical characteristics of the MR fluid squeeze film damper be controlled by a simple external magnetic field, but also the applied voltage required to dramatically change the dynamic characteristics of the MR fluid squeeze film damper is much lower. The MR fluid squeeze film damper is a very effective way to control the vibration of a rotor system.

Comparative Observation of Ar,Ar-H_2 and Ar-N_2 DC Arc Plasma Jets and Their Arc Root Behaviour at Reduced Pressure

Results observed experimentally are presented, about the DC arc plasma jets and their arc-root behaviour generated at reduced gas pressure without or with an applied magnetic field. Pure argon, argon-hydrogen or argon-nitrogen mixture was used as the plasma-forming gas. A specially designed copper mirror was used for a better observation of the arc-root behaviour on the anode surface of the DC non-transferred arc plasma torch. It was found that in the cases without an applied magnetic field, the laminar plasma jets were stable and approximately axisymmetrical. The arc-root attachment on the anode surface was completely diffusive when argon was used as the plasma-forming gas, while the arc-root attachment often became constrictive when hydrogen or nitrogen was added into the argon. As an external magnetic field was applied, the arc root tended to rotate along the anode surface of the non-transferred arc plasma torch.

Progress in organic spintronics

Recent progress in organic spintronics is given an informative overview, covering spin injection, detection, and trans-port in organic spin valve devices, and the magnetic field effect in organic semiconductors （OSCs）. In particular, we focus on our own recent work in spin injection and the organic magnetic field effect （OMFE）.

Magnetic Field Effects on Photoreduction Reaction of 2-Methyl-1,4-Naphthoquinone in Brij 35 Micellar Solution with Additional Radical

A study was made of magnetic field effects (MFEs) on the photoreduction reaction of 2-methyl-1,4-naphthoqui- none (MNQ) in Brij 35 micellar solution containing 4-lauroylamino-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) radical (L-R) under magnetic fields below 1.75 T by a nanosecond laser flash photolysis technique. The triplet MNQ mainly underwent the hydrogen abstraction from Brij 35 molecule to give a radical pair. The escaped radical yield increased with magnetic fields from 0 to 0.62 T and then saturated from 0.62 to 1.75 T. MFEs for both sys-tems can be explained by the relaxation mechanism. However, it was supposed that additional radical, L-R affected the MFEs mainly through enhancing the spin-spin interactions of radical pairs. The effect of the micelle size on MFEs of the studying system was also discussed.