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A novel Fe-Cr-B-C-Al-Si-Mn composite coating was designed and synthesized on 2Cr13 steel substrate using laser cladding technique in this study. The microstructure evolution, microhardness and wear resistance of the composite coating were investigated. The results showed that the microstructure of the coating was mainly composed of α-(Fe,Cr,Al) martensite, retained γ-Fe, and the eutectic comprised of CrFeB, M3(C,B)2, M2(B,C) and M23(C,B)6. The average microhardness of the coating (742.1 HV0.5) was 3.95 times compared with the 2Cr13 steel substrate, and the wear resistance was enhanced by 12.5 times compared with the 2Cr13 steel substrate. The wear mechanisms were dominated by abrasive wear and oxidative wear.

The cyclic oxidation behavior of Hf/Y-doped B2 FeAl intermetallics at 1373 K was investigated. For an undoped FeAl alloy, premature spallation of the alumina film occurs due to the formation of numerous voids at the film/alloy interface and apparent shrinkage in the film. In contrast to this, doping with either Hf or Y significantly improves the interfacial adhesion between the alumina film and the alloy substrate, particularly with Hf-doping. Microstructural observation in combination with Auger electron spectroscopic analysis suggests that in addition to prohibiting interfacial void formation and alleviating film shrinkage, the addition of Hf in the FeAl alloy could consolidate the film/alloy interface by directly participating in chemical bonding across the interface as a Hf ion. This causes the spallation of alumina film from the equiaxed grains/columnar grains interface rather than the bottom of the film.

In this paper, graphene@cuprous oxide (rGO@Cu2O) nanocomposite was designed and prepared with graphene oxide, CuSO4, NaOH and L-ascorbic acid via an in-situ reaction process, and the as-prepared rGO@Cu2O nanocomposite was characterized by XRD, FT-IR, Raman spectroscopy, XPS, SEM-EDS and TEM. The results reveal that the rGO@Cu2O nanocomposite is of homogeneous distribution, and the Cu2O nanoparticles adsorbed on graphene sheets are with a fairly uniform size of 2.3 nm. The rGO@Cu2O/acrylic resin self-polishing marine antifouling paint with functional surfaces was also prepared in this work, and a series of measurements were carried out for the obtained product. The WCAs of paint is up to 113°, and the adhesive force is averaged to 3.69 MPa. After being immersed into seawater, the whole bared panels show an abundant growth of marine organisms within 90 days, but the rGO@Cu2O paint coated surfaces are hardly fouled by marine organisms within 365 days. This work demonstrates that in situ synthesis of rGO@Cu2O is a tin-free potential alternative to inhibit biofouling.

A facile method was used to prepare graphene from discarded polyethylene plastic bags in our work. In order to make high-quality graphene, PE plastic bags were ultrasonically cleaned, ball milled and microwave sintered successively. The height of the 2D band was 1.3 times that of the G band, which reveals that the layer number of as-prepared graphene was 1-2. The atomic ratio of C and O for graphene was more than 54, which indicates that it mainly consists of carbon. The size of graphene was within 4-10 μm. Bi-layer sheets were inevitably observed through high resolution imaging of graphene edges. The BET SSA and the electrical conductivity of graphene were 1521.3 m2 g-1 and 4618 S m-1, respectively. This work provides a new approach to large-scale and high-quality synthesis of graphene from waste polluting materials.

Layered adhesive structures are widely used in the aerospace field, and thus their defect detection is a critical part of quality control. Hence, this paper proposes a method to identify bonding defects relying on dynamic time warping (DTW) and simulation analysis. Based on the transfer matrix method, the propagation simulation model of the layered structure is established, and the simulation signal of the normal area and the characteristic interval of the defects are obtained. DTW is adopted to regularize the simulated and the real signals, and then the Pearson correlation coefficient is employed to calculate the regularized signals’ similarity. On this basis, the proposed scheme is considered a similarity imaging method, attaining an appealing identification error for the three- and the five-layered adhesive structure cases examined involving various defect thicknesses and glue layers. Compared to current imaging methods, the proposed one demonstrates a better and more effective imaging effect appropriate for bonding defect detection.

Anodic aluminum oxide (AAO) thin films were fabricated in phosphoric acid electrolyte solution via one-step electrochemical anodic oxidation of an Al sheet. The films displayed minimally saturated rainbow rings of structural colors, and pores with depths that decreased symmetrically outward from the center of the films. AAO thin films embedded with Co nanodots were fabricated using the one-step ac electrodeposition method. The composite films showed highly saturated rainbow rings of structural colors, which is due to the Co nanodots efficiently screening reflected light from the Al substrate. Moreover, magnetic Co nanodots were found to tune the physical properties of AAO thin film as a new degree of freedom. After determining that Co@AAO composite films possess magnetism and highly saturated rainbow rings of structural colors, their magnetic and optical properties were studied based on modification of the oxidation voltage and deposition time required to prepare the films.

B2 FeAl intermetallic compounds modified with reactive elements (REs) including Sc and Y were fabricated by vacuum arc-melting, and the isothermal oxidation behavior of the RE-doped alloys at 1373 K was investigated. Both Sc and Y single-doping significantly decrease the alumina film growth rate of the alloys. The alumina film growth rate of Sc + Y co-doped alloy even further reduces compared to that of the Sc and Y single-doped alloys. The synergistic effect produced by Sc + Y co-doping on the growth behavior of alumina was discussed. It could be anticipated that the combined additions of Sc and Y which have matched chemical properties might decrease the alumina film growth rate more effectively and provide FeAl alloys with enhanced oxidation resistance.

Hydromulching is a new mulch product which has positive effects on soil moisture conservation and the inhibition of evaporation. However, current research on its soil moisture conservation effect has mainly adopted the field fixed-point observation method, rather than revealing the soil moisture conservation mechanism from the microstructure of the hydromulching. This paper applied spectrum analysis technology to observe the structure and micromorphological features of hydromulching, which will be able to reveal the mechanism of soil moisture conservation. Three types of hydromulching, based on laboratory preparation, were used to analyze the mechanism of soil moisture, using the infrared spectrometer (FTIR) and environmental scanning electron microscope (ESEM). The results showed that −OH generates intermolecular hydrogen bonds between carboxymethylcellulose sodium (CMC) and polyvinyl alcohol (PVA); the hydrogen bonds were formatted between the molecules of the two components, strengthening their compatibility, which increased the effectiveness of the hydromulching and created a dense mesh structure. ESEM observation results showed that preparation 1's hydromulching coverage had good effects, while preparations 2 and 3 performed poorly. Therefore, we can conclude that hydromulching effectively cements soil particles. Then it can generate the soil membrane structure to reduce evaporation and improve soil moisture conservation function.

Development of high-efficiency millimeter-wave-absorbing materials is important to attenuate electromagnetic pollution occurring due to rapid development of information technology and to defend against radar detection for military stealth technology. In this study, BaTiO3 (BTO)/Co3O4 millimeter-wave absorption composite powders with hierarchical microstructures were successfully prepared by the sol–gel method. The results indicated that the Co3O4 phase was preferentially formed at low temperature of 800–900 °C and BTO was formed at high temperature of 1000–1100 °C. A composite with perfect crystallization of both constituent phases and uniform microstructure was obtained when its molar ratio of BTO/Co approached 1 and the sintering temperature was around 900 °C. Both permittivity and permeability resonances were generated typically in composites, due to which er and μr values were relatively closer and e′′ and μ′′ were high at high-frequency range of 30–40 GHz. In the composite with molar ratio of BTO/Co of 4/6 sintered at 900 °C, double absorption peaks with appropriate frequency difference were generated, and absorption intensity from −40 to −50 dB and bandwidth of 5 GHz were successfully obtained with sample matching thickness of 1.8 mm around 35 GHz. It completely covered the atmosphere window at 35 GHz, which has the strongest transparency of millimeter wave. This composite can be used as a highly efficient absorption material of millimeter-wave rays.

The accurate detection and imaging of small debonded regions in a 3-layer ceramic matrix composite (CMC) with two bonded layers is a challenge within terahertz (THz) nondestructive detection. To solve this problem, an improved imaging method for detecting bonding defects is proposed based on the statistical characteristics of variance and kurtosis to detect defects in the upper/lower adhesive layers in a multilayered CMC. The proposed method can ultimately realize a detection accuracy of 50 and 250 μm for bonding defects in the upper and lower adhesive layers, respectively, and achieve a better imaging result compared with power imaging method. Moreover, there is a corresponding relationship between the statistical characteristic value and the bonding defect size—the larger the statistical characteristic value, the larger the bonding defect size—which can be used as a reference to quantify the defect size.

We propose a THz nondestructive analysis method based on multiple echoes and feature fusion. Conventionally, it is difficult to identify the debonding defects of the glue layer (II) due to the thin adhesive layer. To this end, a THz propagation model is established, and a quantitative method for determining the thickness of debonding defects based on multiple echoes is presented. The measurement error for preset defect thickness of 500 µm was 4%. Further, for determining the area of debonding defects, a feature fusion imaging algorithm is proposed to realize the lateral recognition of defects and quantitative analysis is used to improve the recognition ability of defects.

On the basis of the density functional theory of the first-principles, we employ the plane wave pseudopotential method and local density approximation to optimize the geometrical structure of cubic boron nitride and hexagonal boron nitride; then we study their mechanical properties, electronic structures and optical properties at zero temperature and zero pressure, and the thermodynamic properties at different temperatures and different pressures. By means of geometry optimization, we systematically investigate the elastic constant, bulk modulus, shear modulus, hardness and phonon spectrum for each of cubic boron nitride and hexagonal boron nitride. The results show that both cubic boron nitride and hexagonal boron nitride are structurally stable and brittle materials. Besides, cubic boron nitride is more stable than hexagonal boron nitride and it can be used as a superhard material. However, the thermal stability of hexagonal boron nitride is poor. The research results of electrical properties show that both cubic boron nitride and hexagonal boron nitride are indirect bandgap semiconductors, and the localization of cubic boron nitride is stronger than hexagonal boron nitride. The optical studies show that both cubic boron nitride and hexagonal boron nitride have good passivity to incident light. The c-BN is more sensitive to the incident light in high energy region. Last but not least, the thermodynamic properties of cubic boron nitride at high temperature and high pressure are also investigated. The relationships of thermodynamic expansivity, heat capacity, Debye temperature and Grüneisen parameter of c-BN with temperature and pressure are obtained. And the heat capacity of cubic boron nitride is found to be close to the Dulong-Petit limit at high temperatures. In this paper the relevant properties of cubic boron nitride and hexagonal boron nitride under high pressure are described theoretically, and a relatively reliable theoretical basis is provided for relevant experimental research.

According to the constitutive relation built based on the uniaxial tensile and compression tests of ECC, we proposed the calculation theory of flexural capacity of cross section of CFRP-ECC based on plain cross-section assumption. According to the result of four-point bending test, we proved the validity of calculation theory by comparing and analyzing the result of calculation theory and test. The comparison show that result of the calculation theory of flexural capacity of cross section and test agrees well, and the maximum error is under 4%.This research result can provide reference for the structural calculation of non-metallic reinforced high toughness cementitious composites. Introduction How to increase the deformation and improve the brittleness of concrete, and these problems has caused the attention of the scholars both at home and abroad. Engineered Cementitious Composites [1-3] ,which is a short fiber reinforced cement based on fracture mechanics, microscopic physical mechanics and statistical optimization design. The fiber volume is not more than 2.5% of the total volume, and has strain hardening and fracture characteristics under tensile load. The stable tensile strain can reach above 3%,and material specimen shows that the maximum crack width can be controlled within 100 microns .Due to the material toughness and good durability can solve the above problems, both at home and abroad have been applied in practical engineering, such as the Hong Kong-Zhuhai-Macao bridge in our country and Japan yokohama, building, etc. Traditional reinforced concrete structures are easily to cause the loss of bearing capacity and eventually led to the problem of poor durability, because cracking in the process of use within the vulnerable to environmental impact and corrosion of reinforcement. In order to solve this problem, experts and scholars try using high-performance materials instead of steel so as to improve the structure durability. CFRP [4] is a high performance carbon fiber composite material composed of carbon fiber and matrix .It has light weight, high strength, corrosion resistance, fatigue resistance and other advantages. It is better to solve the problem of the durability of steel caused by corrosion instead of steel in concrete members. There is significant difference between reinforced concrete and CFRP-ECC materials in constitutive relation and ordinary reinforced concrete normal section flexural analysis theory is not applicable. Based on ECC uniaxial tensile and compressive constitutive relation, and combination of CFRP tensile stress-strain relationship, we put forward the normal section flexural bearing capacity calculation theory suitable for CFRP-ECC structure. At the same time, from the four-point bending test of CFRP-ECC specimen, we are trying to prove the correctness of the computational theory through the comparison and analysis. 2nd Annual International Conference on Advanced Material Engineering (AME 2016) © 2016. The authors Published by Atlantis Press 113 The Analysis Theory of Flexural Capacity of Cross Section The Constitutive Relation of ECC Based on the obtained experimental data of uniaxial tension and compression experiments of ECC specimens, fitting the stress-strain curve and the constitutive relations are as follows: 0 1 2 3 4 5 6 7 8 0 1 2 3 4 (to,to) (tp,tp) 3 2 (%) Fitted Curve 1  ( M P a )

The effects of atomic-level mixing are systemically investigated in a multifluid interpenetration mix model, and results are compared with the single-fluid model's simulations and experimental data. It is shown that increasing the model free parameter α, shock Mach number, and the initial density discontinuity makes the mix length and fraction of mixing particle increase, resulting in the lower shock temperatures compared with the results of single-fluid model without mixing. Recent high-compressibility direct-drive spherical implosions on OMEGA are simulated by the interpenetration mix model. The calculations with atomic mixing between fuel and shell match quite well with the observations. Without considering any mixing, the calculated neutron yields and ion temperatures are overpredicted; while inclusion of the interpenetration mix model with the adjustable parameter α could fit the simulated neutron yields and ion temperatures well with experimental data.

The control and handling of fluids is central to many applications of the lab-on-chip. This paper analyzes the basic theory of manipulating different electrolytes and finds the two-dimensional model. Coulomb force and dielectric force belonging to the body force of different electrolytes in the microchannel were analyzed. The force criterion at the interface was concluded, and testified by the specific example. Three basic equations were analyzed and applied to simulate the phenomenon. The force criterion was proved to be correct based on the simulation results.

Nanosecond-pulse discharge can produce low-temperature plasma with high electron energy and power density in atmospheric air, thus it has been widely used in the fields of biomedical science, surface treatment, chemical deposition, flow control, plasma combustion and gas diode. However, some phenomena in nanosecond-pulse discharge cannot be explained by traditional discharge theories (Townsend theory and streamer theory), thus the mechanism of pulsed gas discharge based on runaway breakdown of high-energy electrons has been proposed. Generally, the generation and propagation of runaway electrons are accompanied by the generation of X-ray. Therefore, the properties of X-ray can indirectly reveal the characteristics of high-energy runaway electrons in nanosecond-pulse discharges. In this paper, in order to explore the characteristics of runaway electrons and the mechanism of nanosecond-pulse discharge, the temporal properties of X-ray in nanosecond-pulse discharge are investigated. A nanosecond power supply VPG-30-200 (with peak voltage 0200 kV, rising time 1.2-1.6 ns, and full width at half maximum 3-5 ns) is used to produce nanosecond-pulse discharge. The discharge is generated in a tube-to-plane electrode at atmospheric pressure. Effects of the inter-electrode gap, anode thickness and position on the characteristics of X-ray are investigated by measuring the temporal X-ray via a diamond photoconductive device. The experimental results show that X-ray in nanosecond-pulse discharge has a rising time of 1 ns, a pulse width of about 2 ns and a calculated energy of about 2.310-3 J. The detected X-ray energy decreases with the increase of inter-electrode gap, because the longer discharge gap reduces the electric field and the number of runaway electrons, weakening the bremsstrahlung at the anode. When the inter-electrode gap is 50 mm, the discharge mode is converted from a diffuse into a corona, resulting in a rapid decrease in X-ray energy. Furthermore, both X-ray energies measured behind the anode and on the side of discharge chamber decrease as anode thickness increases. The X-ray energy measured on the side of the discharge chamber is one order of magnitude higher than that measured behind the anode, which is because the anode foil absorbs some X-rays when they cross the foil. In addition, the X-ray energy behind the anode significantly decreases with the increase of the thickness of anode aluminum foil. It indicates that the X-ray in nanosecond-pulse discharge mainly comes from the bremsstrahlung caused by the collision between the high-energy runaway electrons and inner surface of the anode foil. Therefore, increasing the thickness of the anode foil will reduce the X-ray energy across the anode film.

In this letter, we report a novel phenomenon of photoisomerization-induced changes in liquid crystalline azobenzene polymers P12 Langmuir-Blodgette monolayer deposited on gold film by irradiating the monolayer with UV (360 nm) and blue (450 nm) lights, which was investigated by surface plasmon resonance technique. It has been shown that it is possible to switch the refractive indices reversibly by irradiating these films with light of appropriate wavelength.

The measurement based on FFT power spectrum of pulse transient dynamic response of structural silicone sealant damage in Hidden frame supported glass curtain wall was first proposed in the paper. The signal of four testing points was gathered and FFT Power Spectrum was used to analyze. Power spectral main peak frequency of the signal in contributing proportion of the total power (i ƒO ) was taken as a dependent variable of the structural silicone sealant damage length ( a ). Experimental data were fitted to establish a functional relations between i¥ a i¦ and i¥ i ƒO i¦byGaussian function or Lorentzian function, and the small damage value of i¥ a i¦was used to be detected. Research results show that it will be helpful for the application of the structural silicone sealant damage detection technology in the hidden frame supported glass curtain wall.

We have proposed and demonstrated a novel switchable single-longitudinal-mode (SLM), dual-wavelength erbium-doped fiber laser (DWEDFL) assisted by Rayleigh backscattering (RBS) in a tapered fiber in a ring laser configuration. The RBS feedback in a tapered fiber is a key mechanism as linewidth narrowing for laser output. A compound laser cavity ensured that the EDFL operated in the SLM state and a saturable absorber (SA) is employed to form a gain grating for both filtering and improving wavelength stability. The fiber laser can output dual wavelengths simultaneously or operate at single wavelength in a switchable manner. Experiment results show that with the proper SA, the peak power drift was improved from 1–2 dB to 0.31 dB and the optical signal to noise ratio was higher than 60 dB. Under the assistance of RBS feedback, the laser linewidths are compressed by around three times and the Lorentzian 3 dB linewidths of 445 Hz and 425 Hz are obtained at 1550 nm and 1554 nm, respectively. Published version

Porous anodic alumina thin films with rainbow rings were fabricated in oxalic acid electrolyte by one-step electrochemical oxidation of Al sheet. The hole depth and aperture diminish symmetrically outward from the center of the films. The relationship between the density of rainbow rings to the oxidation voltage and the time in oxalic acid solution are discussed. Theoretical study on the formation mechanism of porous anodic alumina thin films with rainbow rings indicates that the effect of carbon rod is similar to carbon dot electrode in the process of anode electrochemical reaction. Result of the theoretical study is consistent with the experimental phenomenology.

A novel and simple pulse Dc bias test system has been established to emulate an isothermal environment for on-wafer characterization of MMIC power amplifiers. Testing results of a Ka band monolithic power amplifier with pulse dc bias show a power output capacity increase of 1.5-2dBm at the frequency of 33GHz

The single-electron capture cross sections for the impact of rare-earth ions Ce+, Ho+ on H2 are measured in the energy range 3-8 keV by `growth rate' method. The measurement also reveals that the incident ions are predominantly in ground state.

Al-Fe alloys have wide potential applications in automobile and aerospace industries due to their high specific strength,high specific stiffness,good stability of microstructure and excellent high temperature strength.However,a wide variety of metastable phases can be formed in Al-Fe binary system,such as Al(Fe) supersaturated solid solution,amorphous and intermetallic phase.In order to better understand the phase formation in Al-Fe alloys,a systematic investigation of microstructure evolution is necessary.In this work,bulk dense Al-5Fe alloys were fabricated by mechanical alloying(MA) and spark plasma sintering(SPS).The phases,microstructures and morphologies of MA powders and the corresponding sintered samples were characterized by XRD,SEM and EDS.Special attention was paid to the effects of different milling times on structural change of phases during MA-SPS process.The results showed that during the MA,the size of alloy powders increased with increasing milling time(0—10 h),and then decreased with further milling time(10—20 h).The(111)_(Al) peaks in XRD spectra of MA powders shifted to higher angles with the increase of milling time,indicating the dissolution of Fe atoms into the Al crystal lattice. Homogeneous Al(Fe) solid solutions were obtained after MA for 20 h.Bulk samples sintered from MA powders of 0 and 10 h contained Al/Al_(13)Fe_4/Al_5Fe_2/Fe layer structure intermetallic phase and tiny Al_(13)Fe_4 phase in the Al matrix.However,bulk sample sintered from MA powders of 20 h contained only relatively small Al_(13)Fe_4 phase in the Al matrix.Based on thermodynamic analysis(effective heat of formation theory) and kinetic analysis(spherical shell model),the primary phase that formed on the interfacial layer of Al/Fe was Al_(13)Fe_4,and then Al_5Fe_2 can be formed by the reaction of residual Fe and Al_(13)Fe_4 for the lower Gibbs free energy of Al_5Fe_2 compared to that of Al_(13)Fe_4,leading to the formation of Al/Al_(13)Fe_4/Al_5Fe_2/Fe layer structure intermetallic phase.The absence of Al_5Fe_2 and Fe phases in sample sintered from MA powders of 20 h were attributed to the complete reaction between relatively small Fe particles and Al melt during SPS process.

In this study, we illustrate the effective medium theories in the designs of three-dimensional composite metamaterials of both negative permittivity and negative permeability. The proposed metamaterial consists of random coated spheres with sizes smaller compared to the wavelength embedded in a dielectric host. Simple design rules and formulas following the effective medium models are numerically and analytically presented. We demonstrate that the revised Maxwell—Garnett effective medium theory enables us to design three-dimensional composite metamaterials through the assembly of coated spheres which are random and much smaller than the wavelength of the light. The proposed approach allows for the precise control of the permittivity and the permeability and guides a facile, flexible, and versatile way for the fabrication of composite metamaterials.

Fe doped TiO2 films are deposited on glass substrates using dc magnetron sputtering. The crystal structures and the magnetic properties of these films are studied. Room temperature ferromagnetism is observed in each of all the Fe doped TiO2 films. The source of magnetism is related to an exchange interaction between the transition-metal (Fe) ions and localized strapped holes. The maximal magnetization is observed in a TiO2 film with Fe concentration 7%. With the increase of Fe concentration, the crystal structure of TiO2 film transforms gradually from anatase phase to rutile phases, and magnetism in the film weakened. The changes of crystal structure and crystallization in TiO2 film resulting from Fe doping affect the change of ferromagnetism in the film.

The non-magnetic element Al and magnetic element Co doped ZnO films are prepared by dc magnetron sputtering The films were annealed first in vacuum and then in air. The crystal structures are analyzed by x-ray diffraction (XRD) and magnetic properties are measured by Physical Properties Measurement System (PPMS). The results show that annealing ambience has a great influence on structure and magnetic property of sample Al doped ZnO films annealed in vacuum show no room temperature ferromagnetism, but the ones annealed in air show room temperature ferromagnetism. The room temperature ferromagnetism may be associated with enhanced charge transfer between Al and ZnO films annealed in air. And for Co doped ZnO films annealed in air annealed, the ferromagnetism is weakened. The change of magnetism may be related to the competition between enhanced magnetism resulting from charge transfer between Al and ZnO and reduced magnetism resulting from interstitial Co atoms oxygenated.

Arrays of Ni1-xMnxFe2O4 (x = 0.0, 0.25, 0.5, 0.75) nanowires with an average diameter of about 80 nm are prepared by porous anodic aluminum oxide membrane poured sol technique. X-ray diffraction analysis shows that the nickel manganese ferrites nanowires with cubic spinel structure are synthetized. Scanning electron microscopy and transmission electron microscope images indicate that the nanowire arrays are composed of prolate spheroids with different crystal orientations. Magnetic measurements show that saturation magnetization increases and then decreases with Mn increasing. The change is related to the location and the substitution of ion in spinel structure. Compared with of block material NiFe2O4, the saturation magnetization of nickel ferrite nanowire arrays is low. This is due to the fact that the noncollinear magnetic structure in nanowire arrays become predominant.

CoxZn1−x nanorod arrays were fabricated by electrodeposition in porous anodic aluminum oxide templates at different electric potentials. X-ray diffraction and transmission electron microscopy indicate that highly-ordered and uniform nanorods have been fabricated. The amounts of Co and Zn contents are investigated using energy dispersive spectroscopy, which demonstrates that the atom ratio of the alloy nanorods changes with the deposition potential. In addition, magnetic measurements show that the magnetic isotropy Co-rich CoZn nanorods will change to magnetic anisotropy nanorods with the easy axis parallel to the rod long axis with decreasing Co content.

Using the reactive radio-frequent magnetron sputtering method, ZnO thin films were deposited on pretreated (100) sapphire substrates. The effect of substrate pretreatments on the growth of ZnO films was studied with the structural and morphological characterization using atomic force microscopy, reflection high-energy electron diffraction and X-ray diffraction. It was found that both the original substrate and the substrates annealed in vacuum (8×10-4 Pa), nitrogen atmosphere (40 Pa), and oxygen atmosphere (40 Pa) at 750℃ for 4h have the same surface structure that can be indexed to be α-Al2O3 (001). The surface morphologies of the substrates are different from each other. All the ZnO films grown on the substrates are highly c-axis textured. Their morphologies, however, are related to the pretreatment. For the substrate annealed in vacuum, the film has the morphology with -c and +c epitaxial islands, similar to ZnO grown on the untreated substrate. For the substrate annealed in nitrogen, the film has the morphology with only -c epitaxial islands and has quite large grains and surface roughness. For the substrate annealed in oxygen, the films also has the morphology with -c epitaxial islands, but the surface is much smoother. The surface roughness is as small as 15nm.

ZnO thin films were electrodeposited on glasses coated with a transparent-conductive film (InSnO) with different deposition currents. We have studied the dependence of microstructure, morphology and photoluminescence (PL) on the deposition current by X-ray diffraction, scanning electron microscopy and PL measurement at room temperature. We found that all the films show highly c-axis textured structure and the surface morphology is strongly current-dependent. The transmission spectra show that the films have a transmittance higher than 80% in the visible range. The films have an increase in thickness with the deposition current. The PL spectra exhibit two emission bands, an ultraviolet (UV) one from the exciton transition and a visible light one that might emerge from the defects in the films. The UV emission band has an obvious blueshift, which is found to be due to in doping during the deposition. With the increase of deposition current, the UV emission decreases while the visible light emission goes up.

Atomic force microscopy has been applied to study the morphological evolution o f ZnO film on Si(100) and Si(111) substrates with a native oxide layer. With dyn amic scaling of the film morphology at different growth stages, the nucleation a nd growth behavior have been studied for ZnO films deposited by radio-frequency reactive magnetron sputtering. It is found that ZnO film has three nucleation st ages, namely the stages of initial nucleation, low-rate nucleation, and seconda ry nucleation. The growth exponents of the three stages are β1=1.04 ，β2=0.25±0.01 and β3=0.74 for ZnO film on Si(100) and β1=0.51，β2=0.08±0.02 and β3=0.63 for ZnO f ilm on Si(111), respectively. In the initial nucleation stage, the intrinsic def ects on Si substrates may be responsible for the surface roughening and the dens ity of surface defects determines the nucleation density of ZnO films. The growt h behavior of ZnO film is dominated by the diffusion effect and oriented growth mechanism, as well as the coarsening mechanism induced by the lattice mismatch s tress. In the low-rate nucleation stage, few new ZnO islands are detected and t he films are roughened slowly in morphology. The deposition rate plays a role of controlling the morphological evolution and the lattice mismatch stress may be released in this stage. The secondary nucleation of ZnO films may result from th e bombardment of energetic ions or atoms on the surface of Si substrates. In the secondary nucleation stage, shadowing effect may influence the roughening of Z nO films. In the stage of steady growth, ZnO films have a roughness value much l ower than the ones in nucleation stages and grow in the form of columnar grains.

A compensated compact microstrip resonant cell (C-CMRC) with photonic band-gap (PBG) performance is presented in this paper. Two open microstrip stub-lines are added at the center of the compact microstrip resonant cell (CMRC) to compensate for the unbalanced change of inductance and capacitance in low pass band. It can significantly improve the return loss and insertion loss. Furthermore, the C-CMRC with capacitive loading leads to a stronger slow-wave and enlarged stop-band bandwidth. A low pass filter with 3 C-CMRC resonators in series has been designed according to the PBG performance. The period is only 0.15λg due to the slow-wave effect. Comparison with the general PBG period of 0.5λg, the circuit size is reduced effectively. The original CMRC and the C-CMRC with open stub lines are designed, fabricated and measured to validate the improved performance. A low pass filter with 3 C-CMRC resonators is also designed with 1.26dB insertion loss below 1.8GHz and more than 25dB stop-band from 2.6 to 9GHz.

Using the reactive radio-frequency magnetron sputtering method, ZnO films were deposited on Si (001) and quartz substrates at different pressures with a fixed flow ratio of Ar to O2. The influence of working pressure on the crystallinity and growth behavior were studied with the help of characterization of the morphology, microstructure and optical properties of the films by atomic force microscopy (AFM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and transmittance spectra,respectively. It is found that a critical working pressure can be taken as 0.5—1.0 Pa. With increasing the working pressure from 0.1 Pa up to the critical working pressure, the density of ZnO grains decreases and the films have high c-axis orientation with strong in-plane textured feature. When the working pressure exceeds the critical working pressure, the density of ZnO grains is roughtly a constant and the in-plane textured feature disappears. The influence of working pressure on the refractive index, extinction coefficient and optical energy gap is also discussed in the paper.

Bis (trimethylsiloxy) silicon naphthalocyanine (SiNc) LB films were fabricated to align nematic liquid crystals. Films obtained under different surface pressures exhibit different alignment effects. Films obtained under surface pressure of 15mN/m will induce a planar alignment, while those obtained under 30mN/m will induce a homeotropic alignment. Atomic force microscopy reveals that on films prepared under high surface pressure the SiNc molecules stack into separate monomers or aggregates to form lines of nanometer size with molecular macrocycles perpendicular to the surface of the film and the dipping direction of its formation. In addition, there are grooves of molecular size between the stacked SiNc molecular lines. Similar formation occurs in films prepared under low surface pressures, only instead of molecules all lying perpendicular to the surface, many SiNc molecules are lying obliquely to the film surface or even lying on the surface. The mechanism of the liquid crystal alignment is also discussed.

The temperature fluctuation of the stainless steel irradiated by a CW CO2 laser is studied. In the experiment, the temperature fluctuation and the temperature rise is measured by the infrared thermal imagers. It is found that the maximum amplitude of the temperature fluctuation is kept constant with the increase of the laser heating time; this is different from aluminum, low carbon steel, epoxylite and polymethylmethacrylate. This characteristic of the stainless steel is determined by the variance of thermal conductivity and thermal diffusivity with the increase of temperature. A thorough study of the effects of the material thermal properties on the temperature fluctuation is needed.