黄石高新区的“磁场”效应

黄石是一个老工业基地,近代中国工业的摇篮.黄石高新区(又称黄石经济技术开发区)位于黄石市四个城区的几何中心,坐落在美丽的青龙山下,磁湖岸边.黄石高新区,像一块富有"魔力"的磁石,吸引了许多中外客商和一大批高新技术企业在这里投资、聚集,从而带动了地方经济的发展.

The possible implications of magnetic field effect on understanding the reactant of water splitting

Electrochemical water splitting consists of two elementary reactions i.e.,hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Developing robust HER and OER technologies necessitates a molecular picture of reaction mechanism,yet the reactants for water splitting reactions are unfortunately not fully understood.Here we utilize magnetic field to understand proton transport in HER,and hydroxide ion transport in OER,to discuss the possible implications on understanding the reactants for HER and OER.Magnetic field is a known tool for changing the movement of charged species like ions,e.g.the magnetic‐field‐improved Cu^(2+)transportation near the electrode in Cu electrodeposition.However,applying a magnetic field does not affect the HER or OER rate across various pH,which challenges the traditional opinion that charged species(i.e.proton and hydroxide ion)act as the reactant.This anomalous response of HER and OER to magnetic field,and the fact that the transport of proton and hydroxide ion follow Grotthuss mechanism,collectively indicate water may act as the universal reactant for HER and OER across various pH.With the aid of magnetic field,this work serves as an understanding of water might be the reactant in HER and OER,and possibly in other electrocatalysis reactions involving protonation and deprotonation step.A model that simply focuses on the charged species but overlooking the complexity of the whole electrolyte phase where water is the dominant species,may not reasonably reflect the electrochemistry of HER and OER in aqueous electrolyte.

Diffusion of chemically reactive species in third grade fluid flow over an exponentially stretching sheet considering magnetic field effects

This article addresses the magnetohydrodynamics(MHD) flow of a third grade fluid over an exponentially stretching sheet. Analysis is carried out in the presence of first order chemical reaction. Both cases of constructive and destructive chemical reactions are reported. Convergent solutions of the resulting differential systems are presented in series forms. Characteristics of various sundry parameters on the velocity, concentration, skin friction and local Sherwood number are analyzed and discussed.

Quantum current and Coulomb blockade effect in the mutual inductance coupled mesoscopic system with active source

Based on the charge discreteness,the property of quantum current and the effects of Coulomb blockade have been investigated for the mutual inductance coupled mesoscopic system with active source in external magnetic field.The relationships between quantum current and the conditions of Coulomb blockade in the coupled dual-ring system are given here.

Entropy analysis of SWCNT & MWCNT flow induced by collecting beating of cilia with porous medium

In this article, we considers the thermodynamics analysis of creeping viscous nanofluid flow in a horizontal ciliated tube under the effects of a uniform magnetic field and porous medium. Moreover, energy analysis is performed in the presence of an internal heat source and thermal radiation phenomena. The thermal conductivity of base fluid water is strengthened by considering the carbon nanotubes (CNTs). Mathematical formulation operated, results in a set of non-linear coupled partial differential equations. The governed differential system is transformed into an ordinary differential system by considering suitable similarity variables. Exact solutions in the closed form are computed for the temperature, momentum and pressure gradient profiles. In this study, special attention is devoted to the electrical conductivity of the CNTs. Streamlines patterns are also discussed to witness the flow lines for different parameters. Thermodynamics analysis shows that entropy of the current flow system is an increasing function of Brinkmann number, magnetic parameter, nanoparticle concentration parameter and Darcy number.

New correction method for controlled-source electromagnetics source effects

A novel method for source effect correction based on integral equation method is proposed.By taking the electrical horizontal field Ex of current source as an example,the correction method is validated using both simulated data and field data.The results show that the correction method is feasible and effective for isotropic media.When the field data are processed,the correction method normalizes the sources with different geological structures,which eliminates the geological difference among sources,and retains the geological difference among receivers.The correction results are in line with the expectation in whole.

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.

Grain Size Effect on Electrical Conductivity and Giant Magnetoresistance of Bulk Magnetic Polycrystals

By solving the Boltzmann transport equation and considering the spin-dependent grain boundary scattering, the distribution of electrons in grains and the electrical transport properties in the applied magnetic field are studied. With regard to the dominant influence of grain boundary scattering which is taken as a boundary condition for the electrical transport, the grain size-dependent electrical conductivity is investigated. In addition, the reorientation of the relative magnetization between grains brings the change of the electron spin when the magnetonanocrystailine material is subjected to the magnetic field, resulting in the remarkable giant magnetoresistance effect.

Effects of Impurity on the Ground—State Transitions of a Quantum Dot in Strong Magnetic Field

The low-lying spectra of parabolic quantum dots with or without an impurity at the center are investigated.While it has been known that the electron-electron interaction leads to ground-state transitions on magic values of angular momentum in a magnetic field. We show, in this paper, that the implantation of an impurity ion at the center can either enhance or suppress such transitions, depending on whether it is an acceptor or a donor ion.

Effects of Different Spin-Spin Couplings and Magnetic Fields on Thermal Entanglement in Heisenberg XYZ Chain

The effects of spin-spin interaction on thermed entanglement of a two-qubit Heisenberg XYZ model with different inhomogeneous magnetic fields are investigated. It is shown that the entanglement is dependent on the spin-spin interaction and the inhomogeneous magnetic fields. The larger the Ji （i-axis spin-spin interaction）, the higher critical value the Bi （i-axis uniform magnetic field） has. Moreover, in the weak-field regime, the larger Ji corresponds to more entanglement, while in the strong-field regime, different Ji correspond to the same entanglement. In addition, it is found that with the increase of Ji, the concurrence can approach the maximum value more rapidly for the smaller Bi, and can reach a larger value for the smaller bi （i-axis nonuniform magnetic field）. So we can get more entanglement by increasing the spin-spin interaction Ji, or by decreasing the uniform magnetic field Bi and the nonuniform magnetic field hi.

Magnetic Field Effects on Quantum-Dot Spin Valves

We study the magnetic field effects on the spin-polarized transport of the quantum dot （QD） spin valve in the sequential tunneling regime. A set of generalized master equation is derived. Based on that, we discuss the collinear and noncollinear magnetic field effects, respectively. In the collinear magnetic field case, we find that the Zeeman splitting can induce a negative differential conductance （NDC）, which is quite different from the one found in previous studies. It has a critical polarization in the parallel arrangement and will disappear in the antiparallel configuration. In the noncollinear magnetic field case, the current shows two plateaus and their angular dependence is analyzed. Although sometimes the two current plateaus have similar angular dependence, their mechanisms are different. Our formalism is also suitable for calculating the transport in magnetic molecules, in which the spin splitting is induced not by a magnetic field but by the intrinsic magnetization.

Magnetic Effects in the Thermodynamics of the Process of Thinking

The authors have shown that the process of information and thinking can be modeled on the basis of chemical thermodynamics. The authors offer general equations to calculate the thinking of the work of judgment the L and of entropy solutions G in the presence of a magnetic field. As a result, studies have shown that the magnetic effects strongly influence the thermodynamics of the process of thinking.

Comparative Study of the Static Magnetic Field Effects on Growth Rate with Relative Antibiotic Susceptibility in Escherichia coli

We studied the biological effects of different magnetic fields. Identified bacterial strain Escherichia coli （type I） has been exposed to the dipolar magnetic field force （400, 800, 1200 and 1600 Gausses） which prepared locally with incubation for different period times （24, 48 and 72 hrs） at 37℃. The effects were evaluated by optical density （OD） at 600 nm determining their growth density incorporation with negative control and depending of McFarland turbidity standard （0.5）, in addition to its susceptibility to various antibiotics. Results illustrate different forces of magnetic field decreased the growth rate of E. coli in particular at 24 hrs incubation comparing with unexposed or control samples. The magnetic field increased the logarithmic phase within 4-6 hrs of treatment but decreased after 16 to 18 hrs. Furthermore, changes in the antibiotic sensitivity were observed after exposure period of 6 hrs since E. coli cells became more sensitive to certain antibiotics. While after a 16 hrs exposure period, it became more resistant to the same antibiotics comparing with control groups.

Determination of Gravitomagnetic Field Through GRBs or X-ray Pulsars

In gauge theory of gravity, there is direct coupling between the spin of a particle and gravitomagnetic field, which will affect Landau level. In the surface of a neutron star or near a black hole, the coupling energy between spin and gravitomagnetic field can be large and detectable. Precise measurement of the position of spectrum lines of the corresponding emission or absorption can help us to determine the gravitomagnetic field and electromagnetic field simultaneously. The ratio △ Ee/△Ep can be served as a quantitative criteria of black hole. In GRBs or X-ray pulsar, absorption spectral lines of electron were observed. If the absorption spectral lines of electron, neutron and proton can be observed simultaneously, using the method given in this paper, we can determine the gravitomagnetic field in the surface of the star, and discriminate black hole from neutron star.

Effective-Field Theory on High Spin Systems with Biaxial Crystal Field

Based on the effective-field theory with self-spin correlations and the differential operator technique, physical properties of the spin-2 system with biaxial crystal field on the .simple cubic, body-centered cubic, as well as faced-centered lattice have been studied. The influences of the external longitudinal magnetic field on the magnetization, internal energy, specific heat, and susceptibility have been discussed in detail The phenomenon that the magnetization in the ground state shows quantum effects produced by the biaxial transverse crystal field has been found.

Effects of Nonlinear Couplings on Entanglement in a Two-Qutrit Heisenberg XXX Chain under an Inhomogeneous Magnetic Field

This paper investigates the entanglement of a two-qutrit Heisenberg XXX chain with nonlinear couplings under an inhomogeneous magnetic field. By the concept of negativity, we find that the critical temperature increases with the increase of inhomogeneous magnetic field b. Our study indicates that for any ｜K｜ 〉 ｜J｜, or ｜K｜ 〈 ｜J｜ entanglement always exists for certain regions. We also find that at the critical point, the entanglement becomes a nonanalytic function of B and a quantum phase transition occurs.

Magnetic field increase weight and water content in date palm （Phoenix dactylifera L.）

Magnetic field effects on different plant species have been subject of many studies in the last decade. Magnetic fields are known to induce changes in plant metabolism, growth and productivity. In this study, effect of magnetic field on date palm weight and water content has been investigated. Seedlings of date palm were treated with two types of magnetic fields in two separate experiments. In the first experiment, seedlings were treated with static magnetic field SMF using electromagnetic circuit set to produce three levels of magnetic field intensities 10, 50 and 100 mT for different durations （0, 30, 60, 120, 180 and 240 min）. In the second experiment seedlings were treated with alternating magnetic field AMF, using magnetic resonance imaging providing 1500 mT for 0, 1, 5, 10 and 15 min. After two months of exposure, plants growth parameters （fresh, dry weights and water content for both leaves and roots） were recorded. The measurements revealed that leaf fresh, dry weight and water content increased significantly in response to SMF treatment. Similarly, roots fresh weight and water content were increased significantly; however roots dry weight increasing were insignificant. In the second experiment, AMF has affected plant growth all parameters were increased significantly. Measurements reached the highest level at 15 min of exposure. This study revealed that magnetic fields affect date palm growth parameters by increasing osmotic pressure and water potential which increase water absorption and enhance flesh weight.

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.

Decoherence Effect in An Anisotropic Two-Qubit Heisenberg XYZ Model with Inhomogeneous Magnetic Field

Taking the decoherence effect into account, the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of inhomogeneous magnetic field is investigated. The time evolution of concurrence is studied for the initial state cos θ｜01） ＋ sin θ｜10） at zero temperature. The influences of inhomogeneous magnetic field, anisotropic parameter and decoherence on entanglement dynamic are addressed in detail, and a concurrence formula of the steady state is found. It is shown that the entanglement sudden death （ESD） and entanglement sudden birth （ESB） appear with the decoherence effect, and the stable concurrence depends on the uniform magnetic field B, anisotropic parameter △ and environment coupling strength γ, which is independent of different initial states and nonuniform magnetic field b.

Casimir Effect for Dielectric Plates

We generalize Kupisewska method to the three-dimensional system and another derivation of the Casimir effect between two dielectric plates is presented based on the explicit quantization of the electromagnetic field in the presence of dielectricsl where the physical meaning of ＂evanescent mode＂ is discussed. The Lifshitz＇s formula is rederived using all the vacuum mode functions, which include the contribution of the ＇evanescent modes＇. Only in the case of the perfect, metallic plates will the evanescent modes become unimportant.