Dielectric properties and temperature increase characteristics of zinc oxide dust from fuming furnace

Cavity perturbation method was used to determine the dielectric properties （ε′,ε″, and tanδ） of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption properties of zinc oxide dust and the feasibility of microwave roasting zinc oxide dust to remove fluorine and chlorine. The dielectric constant, dielectric loss, and loss tangent were proportional to the apparent density of zinc oxide dust. The effects of sample mass and microwave power on the temperature increase characteristics under the microwave field were also studied. The results show that the apparent heating rate of the zinc oxide dust increases with the increase in microwave roasting power and decreases with the increase in the sample mass. The temperature of the samples reaches approximately 800 ＆#176;C after microwave treatment for 8 min, which indicates that the zinc oxide dust has strong microwave-absorption ability.

传奇式的英雄——钱壮飞

(一) 乌江汹涌澎湃的波涛在泣说。 乌蒙连峰挺拔的青松在追思。 被周恩来、邓颖超盛赞为“传奇式的英雄”——前红军总政治部副秘书长钱壮飞,牺牲于黔西北高原金沙县沙土镇后山乡与息烽县流长乡之间的乌江渡口一带,至今已60周年了。 这位前中华苏维埃共和国时期里最杰出的敌工干部、优秀共产党员,在严峻时刻,为保卫当时设在上海的中央机关和中央领导同志的安全,曾作出过重大贡献。正如周恩来在全国解放后,曾多次讲到的那样:“如果没有钱壮飞,我和许多中央领导人,许多在上海工作的同志。

Theoretical Studies on Structures and Spectroscopic Properties of Highly Efficient Phosphorescent [Ru（terpy）（phen）X]＋ Complexes

The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru（II） complexes [Ru（terpy）（phen）X]＋ （terpy=2,2＇,6＇,2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH （1）, X=Cl （2）, X-CN （3）） were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π＊（terpy） type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz （Ru）＋Tr/p（X）--π＊ （terpy） transition with MLCT/XLCT （metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer） character, whereas that of 3 at 529 nm is related to a dyz （Ru）＋π（terpy）-π＊ （terpy） transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm （1）, 913 nm （2）, and 838 nm （3） have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru（II） complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand.

Electrolytic Preparation,Structure Characterization and Electro-chemical Performance of NiOOH

NiOOH was prepared by one-step electrolysis of spherical Ni（OH）2 and the effects of electrolysis parameters were examined. The highly pure NiOOH was obtained after electrolysis at a current density of 60mA.g^-1 and 30℃ with anodic potential controlled in the range of 1.73-1.85V （vs. Zn/ZnO） for 360min. The NiOOH samriles were characterized bv X-ray oowder diffraction （XRD） and scanning electron microscope （SEM） analysis.Resuits indicate that the electrolysis product is spherical NiOOH doped with graphite. Charge and discharge tests show that the prepared NiOOH offers a discharge capacity of over 270mAh·g^-1 at current density of 30mA·g^-1 and can be directly used as cathode material of alkaline Zn/NiOOH batteries. Galvanostatic charge/discharge and cyclic voltammetry （CV） tests reveal good cycling reversibility, of the NiOOH electrode.

Electrodeposition behavior and characteristics of Ni-carbon nanotube composite coatings

Ni-CNT (carbon nanotube) composite coatings were processed by electrodeposition and their hardness and corrosion characteristics were investigated with variations of CNT concentration in an electrolyte solution and electrodeposition current density. With increasing the CNT concentration in the electrodeposition bath and the current density, more CNTs are incorporated into Ni matrix. Hardness values of the Ni-CNT coatings are irrelevant to the CNT concentration in the solution, the current density, and current mode, implying poor adhesion of CNTs to Ni matrix. With increasing the CNT content in the coating, the corrosion resistance of the Ni-CNT composite coating becomes inferior due to the porous microstructure.

Influence of Purity Degree on the Evolution the Mechanical Properties of Aluminium Commercial

The influence of the purity degree of the commercial aluminium on the mechanical properties： elastic stress, tensile strength, Brinell hardness, resilience and elongation at break was investigated. It was found that the first three resistance characteristics decrease with the growth of the purity of the material chosen to the detriment of two ductility characteristics that rise to the three states considered： crude of casting noted： F, Annealed noted： O, hardened noted ： H1/4. Furthermore, it is important to note that the hardened and the annealed lead respectively to a considerable hardening and a considerable softening. This hardening and this softening of the material in question can be respectively associated with the increase in dislocation density and immigration impurity elements of dislocations.

Screening Effect in Charge Qubit

We study the influence of screening effect on quantum decoherence for charge qubit and the process of quantum information storage. When the flux produced by the circulating current in SQUID loop is considered, screening effect is formally characterized by a LC resonator. Using large-detuning condition and Fr6hlich transformation in the qubit-cavity-resonator system, we calculate the decoherenee factor for charge qubit and the effective qubit-cavity Hamiltonian. The decoherence factor owns a factorized structure, it shows that screening effect is a resource of decoherence for charge qubit. The effective Hamiltonian shows that the screening effect results in a frequency shift for charge qubit and a modified qubit-cavity coupling constant induced by a LC resonator.

Selective Sensing Characteristics of Ca Doped BeO Nano-sized Tube toward H20 and NH3

By means of density functional calculations, the structural and electronic properties of chemical modification of pristine and Ca-doped BeO nanotubes were investigated with NH3 and H20 molecules. It was found that the NH3 and H20 molecules can be adsorbed on the Be atom of the tube sidewall with the adsorption energies of about 36.1 and 39.0 kcal/mol, respectively. Density of states analysis shows that the electronic properties of the BeONT are slightly changed after the adsorption processes. Substitution of a Be atom in the tube surface with a Ca atom increases the adsorption energies by about 7.4 and 14.7 kcal/mol for NH3 and H20, respectively. Unlike the pristine tube, the electronic properties of Ca-doped BeONT are sensitive to NH3 and H20 molecules. Also, the Ca-doped tube is much more sensitive to H20 molecule than NH3 one.

Progress on RE2O3-Mo/W matrix secondary emitter materials

Two types of secondary emitter materials, the rare earth oxides(RE_2O_3) doped Mo cermet cathodes and the Y_2O_3-W matrix pressed cathode, are introduced in this paper. According to the calculation results, Y_2O_3 exhibits the best secondary emission property among Y_2O_3,La_2O_3,CeO_2 and Lu_2O_3. The rare earth oxides co-doped Mo cathodes in which Y_2O_3 is the main active substance exhibit better secondary emission property than single RE_2O_3 doped Mo cathode. The results obtained by the Monte-Carlo calculation method show that the secondary electron emission property is strongly related to the grain size of the cathode. The decreasing of the grain size reduces the positive charge effect of the rare earth oxide due to the electrons supplement from the metal to the rare earth oxide, whereby the secondary electrons are easier to escape into the vacuum. Y_2O_3 is introduced into Ba-W cathode to fabricate a pressed Y_2O_3-W matrix dispenser cathode. The result indicates that the secondary emission yield of the Ba-W cathode increases from 2.13 to 3.51 by adding Y_2O_3, and the thermionic emission current density(J_0) could reach 4.18 A/cm^2 at 1050 ℃b.

The Effect of Magnetic Field on an Asymmetrical Gaussian Potential Quantum Well Qubit

Under the influence of an applied magnetic field(MF), the eigenenergies and the eigenfunctions of the ground and the first excited states(GFES) are obtained by using a variational method of the Pekar type(VMPT) in a strong electron-LO-phonon coupling asymmetrical Gaussian potential quantum well(AGPQW). This AGPQW system may be employed as a two-level qubit. The numerical results have indicated(i) that when the electron situates in the superposition state of the GFES, we obtain the time evolution and the coordinate change of the electron probability density in the AGPQW,(ii) that due to the presence of the asymmetrical potential in the growth direction of the AGPQW, the probability density shows double-peak configuration, whereas there is only one peak if the confinement is a two dimensional symmetric one in the xy plane of the AGPQW,(iii) that the oscillatory period is a decreasing function of the cyclotron frequency of the MF, the height of the AGPQW and the polaron radius,(iv) and that as the range of the confinement potential(RCP) decreases the oscillatory period will decrease firstly and then increase and it will take a minimum when R =-0.234 nm.

Structural, electronic, and optical absorption properties of TiO_2 nanotube adsorbed with Cu_n clusters

The structural, electronic, and optical absorption properties of TiO2 nanotube （TiO2NT） with Cun clusters （n =1-4） adsorbed on its surface have been investigated based on density functional theory calculations. The TiO2NT is constructed by rolling up a （101） sheet of anatase TiO2 around the [ 1-01 ] direction; the ground states of Cun/TiOzNT systems are determined by analyzing the average adsorption energies. Calculation results show that odd-even oscillations occur for the average adsorption energy, the Cu-O bond length, and the amount of transferred electrons, with the increase in Cu. cluster size; and the Cun/TiO2NTs with odd n＇s demonstrate stronger interaction between the Cu. cluster and the TiO2NT. Also, the impurity states introduced by the Cun cluster to the band gap of TiOzNT cause an obvious redshift of the optical absorption spectrum toward the visible light region, especially for the even n cases.

Effects of manganese dioxide additives on the electrical characteristics of Al-doped ZnO varistors

The effects of manganese dioxide (MnO 2 ) additives on the electrical characteristics of the Al-doped ZnO varistors are investigated. The leakage current densities of the samples decrease first and then increase again with the increase of the amount of MnO 2 additives. Correspondingly, the nonlinear coefficients of the samples keep on increasing and then decrease. In addition, the donor densities increase monotonously with the amount of the doped MnO 2 increasing. The effects of MnO 2 additives on the electrical characteristics of the samples are different from the conclusion of previous literatures. The reasons of the distinct effects are supposed to be related with the donor and interface state densities of the samples.

Relationship between space charge and nonlinear characteristics of ZnO varistor

In order to reveal the conduction mechanism of ZnO varistor, the pulsed electroacoustic (PEA) measurement is employed to investigate the space charge distribution characteristics of ZnO varistors under different current densities in this paper. Experimental results show that the relationship between the space charge and the current density is consistent with the voltage-current characteristics, and can reflect the nonlinear characteristics of ZnO varistor. The space charge increases linearly with the increase of the electric field strength and the current density in the small current region, this reflects the decrease of the surface states of the grain boundary and changes of the Schottky barrier. There exists a transition region between the small current and middle current regions, where the current is composed of the current by the emission of thermally activated electrons and the tunneling current. In the middle current region, the space charge will decrease as the current increases, and will disappear with the depletion layer decreasing to zero.

Near-Origin Structure of the Hooke's Atoms

The Hooke＇s atoms with two or more than two electrons give rise to an interesting quantum mechanical model with valuable practical applications. In this work, we study the electronic properties near the origin of the harmonic potential. It is seen that the spherically averaged density, ~, exhibits an interesting character -- it has only even order terms in its small r expansion. The spherical average of the Hartree potential, ~, and the spherical average of the Kohn-Sham exchange-correlation potential, 9~c, are also shown to have the same property -- all odd order terms in their expansions vanish. F^rthermore, the analysis and results extend also to the case of two-dimensional models. While only models interacting via. the Coulomb potential are primarily considered in the article, the results also extend to models interacting via. other potentials （viz. Van der Waals potential）.

Global characteristics of the second-order ionospheric delay error using inversion of electron density profiles from COSMIC occultation data

It is a well known fact that ionospheric delay error is a predominant factor which influences the positioning accuarcy of GNSS.Although the main part of the first-order ionospheric delay error can be removed by the frequency-dependent behaviors of the ionosphere,the second-order ionospheric delay error must be eliminated to achieve millimetre-scale positioning accuracy.Due to COSMIC occultation providing electron density profiles on the global scale,the paper presents the first-order and the second-order ionospheric delay error analysis on the global scale using the inversion of electron density profiles from COSMIC occultation data during 2009–2011.Firstly,because of the special geographical location of three ISR(incoherent scatter radar),the first-order and the second-order ionospheric delay errors are calculated and discussed;the paper also shows and analyzes the diurnal,seasonal,semi-annual variation of ionospheric delay error with respect to signal direction.Results show that for the L1 signal path,the first-order ionospheric delay error is the largest near the equator,which is circa 7 m;the maximum second-order ionospheric delay error are circa 0.6 cm,0.8 cm and 0.6 cm respectively for L1 signals coming from the zenith,the north and the south at 10 degree elevation angles.The second-order ionospheric delay error on the L1 signal path from zenith are the symmetry between 15°and 15°with respect to magnetic equator,and are nearly zero at the magnetic equator.For the first time,the second-order ionospheric delay error on the global scale is presented,so this research will greatly contribute to analysing the higher-order ionospheric delay error characteristics on the global scale.

Electrical analysis of single-walled carbon nanotube as gigahertz on-chip interconnects

The single-walled carbon nanotube （SWCNT） is a promising nanostructure in the design of future high- frequency system-on-chip, especially in network-on-chip, where the quality of communication between intellectual property （IP） modules is a major concern. Shrinking dimensions of circuits and systems have restricted the use of high-frequency signal characteristics for frequencies up to 1000 GHz. Four key electrical parameters, impedance, propagation constant, current density, and signal delay time, which are crucial in the design of a high-quality interconnect, are derived for different structural configurations of SWCNT. Each of these parameters exhibits strong dependence on the frequency range over which the interconnect is designed to operate, as well as on the configuration of SWCNT. The novelty of the proposed model for solving next-generation high-speed integrated circuit （IC） interconnect challenges is illustrated, compared with existing theoretical and experimental results in the literature.

Characteristics of strong-coupling bipolaron qubit in two-dimensional quantum dot in electric field

Based on Lee-Low-Pines(LLP) unitary transformation, this article adopts the variational method of the Pekar type and gets the energy and wave functions of the ground state and the first excited state of strong-coupling bipolaron in two-dimensional quantum dot in electric field, thus constructs a bipolaron qubit. The numerical results represent that the time oscillation period T0 of probability density of the two electrons in qubit decreases with the increasing electric field intensity F and dielectric constant ratio of the medium η; the probability density Q of the two electrons in qubit oscillates periodically with the increasing time t; the probability of electron appearing near the center of the quantum dot is larger, while that appearing away from the center of the quantum dot is much smaller.

Characterization of the charge transport and electrical properties in solution-processed semiconducting polymers

The conventional charge transport models based on density- and field-dependent mobility, only having a non-Arrhenius tem- perature dependence, cannot give good current-voltage characteristics of poly （2-methoxy-5-（2＇-ethylhexyloxy）-p-phenylene vinylene） （MEH-PPV） hole-only devices. In this paper, we demonstrate that the current-voltage characteristics can give a good unified description of the temperature, carrier density mad electric field dependence of mobility based on both the Arrhenius temperature dependence and the non-Arrhenius temperature dependence. Fu^hermore, we perform a systematic study of charge transport and electrical properties for MEH-PPV. It is shown that the boundary carrier density has an important effect on the current-voltage characteristics. Too large or too small values of boundary carrier density will lead to incorrect cur- rent-voltage characteristics. The numerically calculated carrier density is a decreasing function of the distance to the interface, and the numerically calculated electric field is an increasing function of the distance. Both the maximum of carrier density and the minimum of electric field appear near the interface.