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G-C3N4 was supported on the surface of foamed ceramic, and the g-C3N4@foamed ceramic was packed in the photocatalytic reactor in a layered manner. Effects of urea and H2O2 concentration on NO conversion were investigated. Pulse experiments were carried out to investigate the change of NO conversion with time under different concentrations of H2O2. The contribution of each route that NO converted and the selectivities of products were calculated. Results showed that the photo-reduction of NO accounted for 2%, and the photo-oxidation of NO accounted for 14%, and the rest was absorbed by the humidifier. Products include ammonia (NH + 4-N), nitrogen (N2), nitrite (NO- 2-N) and nitrate (NO- 3-N), of which N2 accounted for 9%.

The embedding method of fiber Bragg grating sensors (FBGs) has a significant impact on the measurability and reliability, as a result of the monitoring of FBGs depending on the strain transmission from the measured object. In this study, structural adhesive was used to join the FBGs with steel wire, and the relevant measurability and reliability of the adhesive-bonded FBGs with steel wire were investigated by loading & unloading cyclic test and fatigue test in the application of FBGs to monitor bridge cable force. It was found that there was a linear relationship between the load and the wavelength for both the loading and the unloading phases, and the data line from the loading process was parallel to that of the unloading process. In addition, 200 million fatigue cycles of steel wire decreased slightly the wavelength of FBGs when the steel wire was applied the same load. The differences in load vs. wavelength between loading and unloading phases, and with and without fatigue tests were likely attributed by the mechanical properties of steel wire, namely, the load-displacement curves of steel wire were responsible for the change in load vs. wavelength. Nevertheless, our experimental results indicated that the FBGs bonded steel wire using structural adhesive had an exemplary measurability and reliability, which will find more application in monitoring bridge cables.

The stability of blast furnace temperature is an important condition to ensure the efficient production of hot metal. Accurate prediction of silicon content in hot metal is of great significance to the control of blast furnace temperature in iron and steel plants. At present, the accuracy of most silicon prediction models can only be guaranteed when the furnace condition is stable. However, due to many factors affecting the silicon content in hot metal of blast furnace, and there are large noises, large delays and large fluctuations in the data, the previous prediction results are of limited guiding significance to the actual production. In this paper, combined with the actual situation, the convolution neural network is used to extract the furnace condition characteristics, and then combined with the attention mechanism and the IndRNN model to get the prediction results, so that the prediction can better adapt to the fluctuating data set. The experimental results show that the prediction error of this model is lower than that of other models, which provides a new solution for the research of silicon content in hot metal of blast furnace.

Effects of magnetic dipole interactions on specific loss power (SLP) for Zn0.3Fe2.7O4/SiO2 core/shell nanoparticles (NPs) with identical magnetic core size and varying non-magnetic shell thicknesses were systematically investigated. In the case of thin silica shell, NPs form chain-like structures due to strong dipole interactions between NPs. The chain formation induces additional shape anisotropy. With increasing thickness of the silica shell, the dipole interaction and therefore the anisotropy induced by the dipole interactions decrease. Meanwhile, the hydrodynamic size of the NPs shows a counterintuitive reduction with increasing shell thickness, also due to the decrease in interactions. The magnetic anisotropy and hydrodynamic size affect the SLP through changes in the Neel and Brownian relaxation rates, leading to different field-dependent SLP values for NPs with thin and thick shells.

High quality Zn0.5Co x Fe2.5 – x O4 (x = 0, 0.05, 0.1, 0.15) serial magnetic nanoparticles with single cubic structures were prepared by the modified thermal decomposition method, and Zn0.5Co x Fe2.5 – x O4/SiO2 composite magnetic nanoparticles were prepared by surface modification of SiO2. The magnetic anisotropy of the sample increases with the increase of the doping amount of Co2+. When the doping amount is 0.1, the sample shows the transition from superparamagnetism to ferrimagnetism at room temperature. In the Zn0.5Co x Fe2.5 – x O4/SiO2 serial samples, the maximum value of specific loss power (SLP) with 1974 W/gmetal can also be found at doping amount of x = 0.1. The composite nanoparticles are expected to be an excellent candidate for clinical magnetic hyperthermia.

Tumor-targeted magnetic hyperthermia has recently attracted much attention. Magnetic nanoparticles (NPs) are heat mediator nanoprobes in magnetic hyperthermia for cancer treatment. In this paper, single cubic spinel structural Zn0.3Fe2.7O4 magnetic NPs with sizes of 14 nm–20 nm were synthesized, followed by coating with SiO2 shell. The SLP value of Zn0.3Fe2.7O4/SiO2 NPs below 20 nm changes non-monotonically with the concentration of solution under the alternating current (AC) magnetic field of 430 kHz and 27 kA/m. SLP values of all Zn0.3Fe2.7O4/SiO2 NPs appear a peak value with change of solution concentration. The solution concentrations with optimal SLP value decrease with increasing magnetic core size. This work can give guidance to the better prediction and control of the magnetic hyperthermia performance of materials in clinical applications.

In this paper, Φ 72 × 200 mm LYSO:Ce and Ca-codoped LYSO:Ce crystal boules were grown by the CZ method. The growth conditions were stabilized by controlling the rotation rate to maintain a slightly convex solid-liquid interface shape. Samples 3.9 × 3.9 × 20 mm in size were cut from the crystal boules along the growth direction. The inhomogeneities, including the components and the optical and the scintillation properties, of the as-grown and air-annealed samples were studied. The component analysis showed an increasing trend of Ce and Ca concentrations along the growth direction of the crystals. By combining the defect study of the samples, appropriate ranges of doping concentrations on high-quality LYSO crystal growth were determined. The optical properties, including the emission, excitation and absorption spectra, of the samples were investigated. The spectra indicated the differences of Vo defect, Ce1/Ce2 ratio and Ce4+ content in the samples, which can be related to the scintillation performances. Scintillation studies showed that light output and energy resolution vary greatly from top to bottom of the as-grown LYSO:Ce. These properties can be improved to achieve better uniformity by air annealing and Ca codoping. The light output can reach 106.6 % (relative to a standard sample) with a uniformity of ± 2.6 %, and the energy resolution can reach 9.4 % with a uniformity of ± 0.2 % for the air-annealed Ca-codoped LYSO:Ce samples. In conclusion, this paper describes some factors that will affect the scintillation inhomogeneity and can guide the growth of high-quality LSO/LYSO crystals.

A flexible multibody dynamic calculation model based on thermo-elasto-hydrodynamic lubrication bearing model was established. This numerical simulation method provided a more realistic turbocharger calculation model and a more reliable theoretical support for studying the dynamic vibration characteristics of the floating ring bearing turbocharger system. In order to fully consider the dynamic characteristics of each component, the behavior of the floating ring bearing was described by generalized incompressible Reynolds equation in thermo-elasto-hydrodynamic lubrication model. The flexible body substructure models were established by the modal synthesis method. Based on this model, the direct mathematical model of the relationship between the eccentricity of the rotor and the oil film clearance on the turbocharger’s surface vibration was established. The influence of eccentricity and oil film thickness on the surface vibration of the turbocharger body was calculated by transient dynamics method. The results showed that the eccentricity of the rotor and the vibration of turbocharger housing were monotonic functions, but the interaction between the whirl of internal and external oil films made the mechanism of the influence of the oil film thickness on the turbocharger body’s vibration complicated. The research provided a new idea for the structural vibration and synchronous noise control of the supercharger.

Magnetic properties and the magnetocaloric effect (MCE) of the RSi (R = Ce, Pr, Nd) compounds made of Misch metal (MM) are investigated. Two transitions are found at 12 K and 38 K. Field variation generated large MCE and two peaks are found in the magnetic entropy change (ΔS) curves, which correspond to the two transition temperatures. The maximum values of the magnetic entropy changes (ΔS) are found to be −5.1 J/(kg⋅K) and −9.3 J/(kg⋅K) for the field ranges of 0–2 T and 0–5 T, respectively. The large ΔS as well as ultra-low price of MM make (MM)Si a competitive magnetic refrigerant candidate for low temperature in Eriksson cycle.

Magnetocaloric effect (MCE) technology is considered as one of the most important fundamental thermodynamic effects, and plays an important role in the refrigeration area for its high energy-efficiency and eco-friendly characteristics. Rear earth based low temperature magnetic refrigerant shows broad application prospect in the future. Low cost and high processability are so important to the application in the refrigeration machine. In this paper, pure phase TbFe2Al10 was prepared by arc melting and long-time annealing process. The magnetic properties and magnetocaloric effect (MCE) of the TbFe2Al10 compound were intensively studied. It was determined to be antiferromagnetic with the Neel temperature TN =18 K. Two metamagnetic transitions from antiferromagnetic (AFM) to ferrimagnetic (FIM) and ferrimagnetic to ferromagnetic (FM) state occurred at 5 K under a crucial applied magnetic field of 0.95 T and 1.89 T, respectively. Field variation generated a large MCE and no magnetic hysteresis loss was observed. The maximum values of magnetic entropy change (ΔS) were found to be -4.5 J/kg K and –6.7 J/kg K for the field changes of 0-5 T and 0-7 T, respectively. The large ΔS with no hysteresis loss as well as low proportion of rare earth (Tb) in crude materials make TbFe2Al10 a competitive candidate as low temperature magnetic refrigerant.

The hexagonal prism shaped crystal shows potential to design a PET system for its higher ray blocking efficiency and equidistance with neighbors. This paper proposed a honeycomb PET based on hexagonal prism shaped scintillation crystals. Its performance was evaluated and compared with a traditional PET system based on rectangular prism shaped crystals by GEANT4 simulation. The results show that the sensitivity is enhanced from 2% to 5% in most positions of the field of view (FOV). Meanwhile, the axial, radial and tangential spatial resolution are both improved in the positions near the center of the FOV (0mm, 10mm radial offset), but deteriorated with the offset become larger.

By performing first-principles calculations based on the density functional theory we optimized the geometric structures of TmZn15S16(Tm=V,Cr,Mn) and determined their magnetic properties.TmZn15S16 are typical half-metallic ferromagnets.The supercell magnetic moments of VZn15S16,CrZn15S16,and MnZn15S16 are 3.0099μB,3.9977μB,and 5.0092μB,respectively,and these arise mainly from the Tm ions.The half-metallicity of CrZn15S16 is more stable than that of VZn15S16 and MnZn15S16.These half-metallic ferromagnets have wide spin gaps.Therefore,high Curie temperatures are possible.The electronic structures of the V,Cr,and Mn ions are eg2↑t12g↑,eg2↑t 22g↑,and eg2↑t 32g↑,respectively.

Considering the anharmonic vibrations and the interactions between electron and phonon of atoms, in this article we study the temperature dependence of Grneisen parameter, thermal expansion coefficient at low temperature and phonon relaxation time by using the theory and method of solid state physics. The influences of the anharmonic vibration of the atom on the above parameters are further discussed. The obtained results are as follows. 1) The thermal expansion coefficient of graphene is a negative value when the temperature drops below room temperature. The absolute value of the thermal expansion coefficient of graphene increases monotonically with the increase of temperature. The thermal expansion coefficient of graphene is-3.64×10-6 K-1 at room temperature. 2) The value of Grneisen parameter is zero in the harmonic approximation. If the anharmonic vibration is considered, the Grneisen parameter will increase slowly with the increase of temperature. Its value is between 1.40 and1.42 and the change is almost linear. And we find that the influence of the second anharmonic term is less than that of the first anharmonic term on Grneisen parameter. 3) The phonon relaxation time decreases with the increase of temperature. The rate changes rapidly at low temperature (T

The atomic anharmonic vibration and the electron-phonon interaction are considered, and then a physical model about the metal-based epitaxial graphene is built. Variations of the electrical conductivity and the Fermi velocity with temperature for the metal-based epitaxial graphene are given based on the solid state physics theory or method. The alkali-metal epitaxial graphene is selected as the substrate, and then the influences of substrate material, electron-phonon interaction and the anharmonic vibration on the electrical conductivity and the Fermi velocity of epitaxial graphene are discussed. Some results are shown as follows. Firstly, at zero temperature, the electrical conductivity and the Fermi velocity of the alkali-metal-base epitaxial graphene increase with the number of the atoms in substrate material increasing. Secondly, the electrical conductivity of epitaxial graphene decreases with temperature rising. Furthermore, the variation rate also decreases with temperature rising. Generally, the electrical conductivity originates mainly from electrons and phones. The electronic contribution to the electrical conductivity varies with temperature slowly, but the phone contribution to electrical conductivity varies with temperature evidently. Therefore, the contribution of phonons to electrical conductivity is much larger than that of electrons. Furthermore, the contribution increases with the number of atoms in basal elements. The phonon contribution to conductivity decreases with temperature rising, but it is unrelated to the basal elements. Thirdly, the Fermi velocity of the epitaxial graphene increases with temperature slowly. The variation of the Fermi velocity with temperature decreases with the increase of interaction between the graphene and the basal atoms. However, it increases with the number of atoms of the basal materials. The anharmonic effect causes important influences on the electrical conductivity and the Fermi velocity. Under the harmonic approximation the velocity is constant. However, the conductance increases rapidly with temperature. With considering the atomic anharmonic terms, the Fermi velocity increases with temperature. The variation of the electrical conductivity with temperature increasing becomes slower. If the temperature is higher, the anharmonic effects become more evident.

Twenty-five new R-branch lines of the v2 (1−←0+) band of H3O+ are measured using diode laser velocity modulation spectroscopy between 1070 and 1230 cm−1. The H3O+ ions are produced in a high voltage ac discharge with water diluted in helium. The observed lines together with all the previously published measurements are fit to the standard vibration-rotational Hamiltonian of an oblate symmetric top, yielding a set of improved molecular constants. All the sextic centrifugal distortion constants for both 0+ and 1− states are determined precisely. The observed R(13,0) transition is shifted about -0.129 cm−1 from its calculated value, indicating that a near degeneracy exists between the (13, 0)+ and (13, 3)− ground-state rotation-inversion levels.

As an h.c.p crystal structure with only a few limited slipping planes, the AZ31 magnesium alloy exhibits a bad plasticity in the presence of external stress. Due to its low density, advanced damping capacity and high ratio strength and rigidity, the magnesium alloy has gradually become the focused and potential structural and functional metallic material in the diverse fields of aerospace, aviation and vehicle transportation, electronic products, etc. Therefore, it is of great importance to improve the process ability of conventional magnetism alloy as AZ31. In the past decades many approaches have been proposed in order to improve the plastic deformation capability. Among these, the diverse physical fields are regarded as the effective methods to improve the comprehensive mechanical properties of metallic materials due to their peculiar heat, force and quantum effects together with the advantageous characteristics of low pollution and high efficiency. In the paper, on the basis of previous researches, a high pulsed magnetic field is introduced into the tensile test to study the influences of magnetic field on the plasticity and microstructure of AZ31 magnesium alloy in order to explore a novel way to enhance the plastic deformation capability of alloy. As for the current experiment, the tensile test of AZ31 magnesium alloy is carried out under the coupling action of high pulsed magnetic field and external stress. The test results are compared with those processed without magnetic field. Several advanced detection methods are utilized to investigate the microstructure including the electron back scattered diffraction, X-ray diffraction and transmission electron microscopy, etc. Besides, the first principle is utilized to calculate the magnetic properties of main precipitates (Mg17Al12).The experimental results show that the tensile strength and elongation of the 3 T sample are increased by 2.2% and 28.7% in comparison to those of the 0 T sample. It highlights that when the high pulsed magnetic field is introduced into the plastic deformation process, the plasticity of the magnesium alloy can be improved without reducing the tensile strength of the material. The action mechanism of magnetic field is analyzed in detail and attributed to the magnetoplasticity effect. The calculation results on the basis of first principle show that the (Mg17Al12) phase is paramagnetic, which is helpful for performing the effect of magnetic field. The magnetic field enhances the flexibility of the dislocation movement and facilitates the proliferation of the dislocation. The dislocation and stress concentrating at the grain boundaries accelerate the formation of recrystallization, which is of great importance to the sub-grain generation and grain refinement that is beneficial to exhibiting the fine grain strengthening and enhancing the strength and toughness of alloy. Meanwhile, during the peculiar tensile process, the magnetic field induces the grain rotation. The newborn fine grains along the non-basal face weaken the (0001) basal texture of magnesium alloy. The characteristic of the texture structure is helpful for improving the plastic deformation capacity of AZ31 alloy. The plastic deformation under high magnetic field is regarded as an advanced way to improve the plasticities of similar nonmagnetic metallic materials such as aluminum, titanium and copper alloys and their composites.

We describe a PVK-based photorefractive polymer composite doped with disperse red 1, poly-butylacrylate and TNF. Using the two-beam coupling experiment, we investigate its photorefractive properties as well as the dynamic process of the index gratings in the sample. We observe the photorefractive effect in the absence of an applied external electric field. The two-beam coupling gain coefficient was measured to reach a value as high as 140 cm-1 in the absence of an external applied electric field and a value of 470 cm-1 at a poling dc electric field of 25V/µm.

The plasticity of material is associated closely with the movement and proliferation of dislocation. Therefore, in the deformation and plasticity theory the dislocation kinetics is an important topic. In the case of no magnetic field, the conventional dislocation kinetics normally focuses on the dislocation microstructure, nucleation and mobility, and the inherent relationship between electron spin and plasticity is seldom concerned. As a matter of fact, the electron rotation is directionless and unordered in the absence of magnetic field, so the electron behavior will not take an apparent effect on the microstructure and properties of material. Nevertheless, in the presence of magnetic field the case is different. The magnetic field will influence the electron spin and, therefore, atomic rearrangement. The dislocation behavior and plasticity will also be affected by the magnetic field, which is called the magnetoplastic effect. In this paper, on the basis of magnetoplastic effect the dislocation kinetics involving dislocation stress, mobility and others is discussed both qualitatively and quantitatively. It has rarely reported currently in the literature. The pulsed magnetic field is first utilized to process solid nanometer alumina particulates reinforced aluminum matrix composites. The experimental results demonstrate that the dislocation density increases with magnetic induction intensity increasing from zero to 3 T. The phenomenon reveals the characteristic of plastic deformation in a processed sample. The further theoretical analysis displays that the generated magnetic force is not large enough to activate the dislocation movement. The fundamental reason lies in the magnetoplastic effect, that is, the magnetic field brings about the transition of electron spin in the radical pairs between paramagnetic dislocation cores and obstacles. The radical pairs tend to be conversed from the singlet state with high bonding energy to the triplet state with low bonding energy, therefore, the prerequisite energy for dislocation to surmount the obstacles will be lowed and the depinning tendency will be apparent. In a period of dislocation movement, the rate limiting consists in the dislocation stopping at the obstacle; on the contrary, the electron excitation and atomic arrangement governed by the magnetic field take negligible time. Hence, it can be seen that the performance of magnetic field is highly efficient. The critical magnetic induction intensity is calculated to be 3 T. That is, when the intensity is lower than 3 T, the magnetoplastic effect becomes strong with the increase of magnetic induction intensity and action time; when the intensity is higher than 3 T, the effect changes gently. Under this critical magnetic induction intensity, the dislocation velocity is deduced to be on the order of 10-3 m/s. Moreover, the dislocation length will be increased by two orders of magnitude. The displacement of dislocation is proportional to the square of magnetic induction intensity and action time of magnetic field. To sum up, the magnetic field treatment has been proved to be an efficient approach to improve the plasticity of material. The prospective research will focus on the mechanical properties of alloys or composites subjected to magnetic field, together with tensile stress so as to acquire the effect of magnetic field parameters of macro plasticity of materials.

In this paper, we introduce a new type of gain guided and index antiguided (GG-IAG) large mode area (LMA) fiber structure, basic theory and its important applications in fiber laser fields. We draw a conclusion that the side pump technology is the most appropriate scheme for GG-IAG LMA fiber after comprehensively analyzing the laser output characteristics and the thermal effect of the fiber under different pump conditions. The theoretical simulations of GG-IAG fiber side pump technology and the side pump experiment process are performed by the V groove technology, which is conducible to the experiment research in relevant fields. Finally, the suggestion of how to reduce the difference between the experimental results and the theoretical results is made and its relevant reason is also discussed.

For aluminum matrix composite, the introduced particles will strengthen the matrix, but as the obstacles, the heterogeneous particles will hinder the dislocation movement, generate uneven material structure, and may become a source of stress concentration. Therefore, they are detrimental severely to the elongation and plasticity of composite. It is known that dislocations exhibit a paramagnetic behavior because they contain paramagnetic centers including localized electrons, holes, triplet excitons, ion radicals, etc. The initial radical pair of the dislocation-obstacle S (spin angular momentum) = ± 1/2 is in a singlet state, and the total spin of the radical pair is 0 and in the antiparallel spin direction, offsetting a magnetism of the radical pair. The magnetic field can change the spin direction from singlet state to triplet state. In the triplet state the electron spin is 1 and in the same spin direction. A strong bond of the dislocation-obstacle is formed only in the singlet state when the spins of the two electrons are antiparallel. So an obstacle is able to pin a dislocation only if the radical pair is in the singlet state. Under the condition of high pulsed magnetic field treatment (HPMFT) the conversion of electronic spin will be a fundamental cause of dislocation motion along a glide plane. The movement of pinned dislocations will change the material microstructure and influence the performance of material. By comparing the microstructural evolutions and the residual stresses of samples subjected to HPMFT with different values of magnetic induced density (B), the positive influence of magnetoplastic effect on the plasticity of aluminum matrix composite is investigated in this paper. The results show that the dislocation density is significantly increased when B changes from 2 T to 4 T. When B=4 T the dislocation density is enhanced by 3.1 times compared with that of the sample without HPMFT. Moreover, the residual stress is reduced apparently from 41 MPa (B=0) to -1 MPa (B=3 T). In the view of atomic scale, the high magnetic field leads to a magnetoplastic effect which contributes to the dislocation movement and promotes the dislocation depinning, thereafter, the number of movable dislocations increases up. From the viewing of the internal structure of composite, the magnetic field accelerates the releasing rate of internal stress and lowers the residual stress in material, which is beneficial to improving the plasticity of aluminum matrix composite.

The influences of atomic number and shape on Debye temperature, surface energy, surface pressure and lattice are studied by means of Me-lennard jones potential, then the influences of anharmonicity and shape on surface character are discussed. The result shows that (1) the Debye temperature and surface energy increase as atomic number increases, and that of rod nanodiamond is lower than that of cubic one. (2) The surface pressure and the variation of lattice parameter at low temperature decrease with the atom number decreasing, and the rod sample change is more apparent. The harmonic atomic surface pressure is smaller than the anharmonic one. (3) The above case is obvious when less atom number is small.

A novel mutual injection phase-locking fiber laser combining technique is proposed， based on a corner-cube and a beam splitter with reflectivity of 50% at 45°， and the mutual injection phase-locking principle is introduced. Mutual injection phase-locking of two individual double clad fiber lasers is experimentally realized, steady interference stripes with high contrast ratio（about 0.57）are observed and more than 10W output power is obtained, which indicates that the power combining efficiency is 76%. Successful attempts of phase lock show that this mutual injection-locking method is a promising technology in the field of fiber laser coherent and the output power can be further scaled.

The relation of Debye temperature with the interaction potential of atoms, the r elation of the mean coordination number with the shape and atomicity are deduce d. Through applying the theory of statistical physics, the variation law of the surface energy of rectangular nanocrystals along with the temperature, atomicit y and shape is obtained, and taking Ar nanocrystal as an example, the influence of shape and atomicity on the surface energy of the nanocrystal is discussed.

The(Ni79Fe21)1-xNbx(5nm)/(Ni79Fe21) (20nm)/Ta(3nm) films are prepared with the (Ni79Fe21)1-xNbx seed layers. The grain size, hyste resis loops and surface roughness of samples are measured and the variations of hysteresis loops with the Nb atomic concentration in the seed layers are analyze d. The results show the microstructure of the permalloy films grown on the seed layers is improved. The coercivity and the (B·H)m in the hysteresis loop is minimal at x=23%. The influence of seed layers on the hysteresis loops is partly duc to the different excitation energy of different seed layers, which result in different roughness of the surface of the seed layers film, hence the different microstructure of the permalloy films.

The photonic band of a set of quasi_fractal photonic crystals, which have similar structure and include idealized metal, is computed by finite-differ ence time_domain method. The result shows that there are photonic band gaps in t his kinds of quasi-fractal photonic crystals. It is found that, with increasing fractal series, the width of the photonic band gap is enlarged, the frequency of the photonic band totally trends to high frequency quickly, at the same time, the photonic band is quickly hauled to line and become a energy level.