Preparation and Properties of Magnesium Oxysulfide Cement Based Foam Board Absorbing Material

In order to better solve the problem of electromagnetic pollution in the civil building cement,to improve the absorption capacity of magnesium oxysulfide cement based materials,and to better use sulfur oxide magnesium cement foamed sheet for improvement of electromagnetic industry,this paper uses the excellent microwave absorbing properties of ferrite and the modified sulfur oxide magnesium cement foam board,and discusses the microwave absorbing performance,aiming at improving the electromagnetic pollution in daily life.The effects of ferrite and silicon carbide doping on microwave absorption properties of modified magnesium oxysulfate cement were studied.At the same time,the wave absorbing properties of the corresponding samples were detected by bow method,and the causes of the corresponding phenomena were analyzed by scanning electron microscopy (SEM).The results show that the lowest reflectance of the material is-17.9 dB at 34.1 GHz and the average reflectance of the whole band is-15.9 dB under the target frequency band of 26.5-40 GHz.Under the action of external magnetic field,the absorbing particles are affected by magnetization force,magnetic dipole and resistance coupling,and play the absorbing effect in the cement base solidified completely in the electromagnetic field environment.The lowest reflectance is-17.3dB at 36.4GHz and the average reflectance is-14.3dB for the whole band.

Immobilization of Oxyanions on the Reconstructed Heterostructure Evolved from a Bimetallic Oxysulfide for the Promotion of Oxygen Evolution Reaction

Efficient and durable oxygen evolution reaction(OER)requires the electrocatalyst to bear abundant active sites,optimized electronic structure as well as robust component and mechanical stability.Herein,a bimetallic lanthanum-nickel oxysulfide with rich oxygen vacancies based on the La_(2)O_(2)S prototype is fabricated as a binder-free precatalyst for alkaline OER.The combination of advanced in situ and ex situ characterizations with theoretical calculation uncovers the synergistic effect among La,Ni,O,and S species during OER,which assures the adsorption and stabilization of the oxyanion SO_(4)^(2-)onto the surface of the deeply reconstructed porous heterostructure composed of confining Ni OOH nanodomains by La(OH)_3 barrier.Such coupling,confinement,porosity and immobilization enable notable improvement in active site accessibility,phase stability,mass diffusion capability and the intrinsic Gibbs free energy of oxygen-containing intermediates.The optimized electrocatalyst delivers exceptional alkaline OER activity and durability,outperforming most of the Ni-based benchmark OER electrocatalysts.

Laser stealth absorbent of samarium oxysulfide prepared by flux method

A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition, morphology, and reflectivity of the powders were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and ultraviolet-visible spectrophotometer （UVPC）. The results showed that pure phase of Sm202S could be obtained with Na2CO3 as flux above 950~C, and the reflectivity decreased with the calcination temperature increasing. Compared with other samarium compounds, the reflectivity at 1064 nm of Sm2O2S was the lowest. Different fluxes had great impact on the phase composition, particle morphology, and reflectivity of the products. In short, Sm2O2S was suitable as a kind of absorbent against 1064 nm laser.

Electrodeposition of Zn(O,S)(zinc oxysulfide)thin films:Exploiting its thermodynamic and kinetic processes with incorporation of tartaric acid

Zn（O,S）（zinc oxysulfide） is an important chalcogenide material recently reported to be potentially applied as electrode buffers in thin film solar cells. Both vacuum and solution approaches have enabled the fabrication of Zn（O,S） films. However they either require extreme conditions and high energy consumption for synthesis, or suffer from lack of controllability mainly due to the thermodynamic and kinetic distinction between Zn O and Zn S during film growth. Here we demonstrated an effective electrodeposition route to obtain high-quality Zn（O,S） thin films in a controllable manner. Importantly, tartaric acid was employed as a secondary complexing agent in the electrolyte to improve the film morphology, as well as to adjust other key properties such as composition and absorption. To elucidate the vital role that tartaric acid played, thermodynamic and kinetic processes of electrodeposition was investigated and discussed in detail. The accumulative contribution has shed light on further exploit of Zn（O,S） with tunable properties and optimization of the corresponding electrodeposition process, for the application in thin film solar cells.

XPS STUDIES OF LITHIUM ION CONDUCTING OXYSULFIDE GLASSES

The results of the photoelectron spectra for the oxysulfide glasses in the Li2S-B2O3 (-LiBr) spotems are discussed. The peak resolved S2p spectra show the existences of bridging and non-bridging S. The values of the binding energy of Lits indicate the chemical environmemts of Li+ ions.

Blue,green,red upconversion luminescence and optical characteristics of rare earth doped rare earth oxide and oxysulfide

The cold isostatic press pretreatment process was adopted to prepare fine rare earth oxysulfide up-conversion phosphors with spherical shape, narrow size distribution and high luminescence efficiency. The upconversion optical characteristics and brightness of the blue (Y2O2SYb,Tm), green (Y2O2S: Yb,Er), red (Y2O3Yb,Er) emitter were also investigated, and a novel method was successfully developed for the brightness measurement of upconversion luminescence (UPL). It is shown that a white color can be obtained by the appropriate mixture of these primary blue, green and red emissions components. The Er3+ ions exhibit different upconversion mechanism in Y2O2S and Y2O3 host materials. The rare earth oxysulfide is an efficient upconversion matrix. The UPL brightness of Y2O2S: Yb,Er is 6.5 times higher than that of Y2O3: Yb,Er, and Y2O2S: Yb,Er shows UPL brightness of 1100 cd/m2 under 5.56 W/cm2 power density using a 980 nm laser diode.

Synthesis and characterization of monodisperse Eu^3＋ doped gadolinium oxysulfide nanocrystals

Gd202S：Eu3＋ nanoparticles were synthesized using two step process consisting of sulfuration of basic carbonates obtained by homogenous precipitation. Annealing of lanthanide nitrates at total concentration of 5x 10^-3 mol/L in a water solution containing relatively high, three molar concentration of urea ensured the optimal conditions for the reproducible preparation of uniform and small spherical particles. During sulfuration step elemental sulfur was mixed with precursor which eliminated necessity of using an auxiliary furnace and provided sulfur-reach reaction atmosphere. Such optimized protocol afforded synthesis of spherical and non-agglomerated nanoparticles with diameter smaller than 100 nm. The precursors morphology was maintained, but particles size was reduced by 15%-20% during sulfuration. The results indicated that higher emission intensity was observed for Gd202S：Eu3＋（8%） oxysulfide sample synthesized using crystalline Gd（CO3）OH precursor, than for that obtained from amorphous Gd2（OH）2（CO3）2.H20 precursor, although some further efforts to improve morphology of the former are still required.

Synthesis and characterization of Y_2O_2S:Eu^(3+),Mg^(2+),Ti^(4+) nanorods via a solvothermal routine

Y2O2S:Eu3+,Mg2+,Ti4+ nanorods were prepared by a solvothermal procedure.Rod-like Y(OH)3 was firstly synthesized by hydrothermal method to serve as the precursor.Y2O2S:Eu3+,Mg2+,Ti4+ powders were obtained by calcinating the precursor at CS2 atmosphere.The Y2O2S:Eu3+,Mg2+,Ti4+ phosphor with diameters of 30–50 nm and lengths up to 200–400 nm inherited the rod-like shape from the precursor after calcined at CS2 atmosphere.The Y2O2S:Eu3+,Mg2+,Ti4+ nanorods showed hexagonal pure phase,good dispersion and exhibite...

Preparation of Nano Y_2O_2S∶Eu Phosphor by Ethanol Assisted Combustion Synthesis Method

Y2O2S：Eu nano crystallines were prepared by a new ethanol assisted combustion synthesis method using sulfurcontained organic fuel in an ethanol-aqueous solution. The as-prepared nanocrystallines were characterized by X-ray diffraction, transmission electron microscope, photoluminescence spectra and X-ray luminescence spectra. It is shown that the assistant fuel ethanol has the effect of decreasing the water needed, simplifying the experiment procedure by dissolving rare earth nitrate and sulfur-contained organic fuel into an even solution, and prompting the formation of rare earth oxysulfide by igniting firstly during heating that leads to combustion decomposition reaction. Y2O2S ： Eu nano crystallines with strong photoluminescence and X-ray luminescence are obtained using thioacetamide as organic fuel. Mixtures of Y2O3 ： Eu and Y2O2S ： Eu are acquired using thiourea as fuel, and the content of Y2O2S ： Eu increases until reaches to about half of the Y2O3 ： Eu with the increasing amount of thiourea. Y2O2SO4 ： Eu emerges when S/Y = 6 and increases with increasing thiourea amount.

A Novel Sr_2CuInO_3S p-type semiconductor photocatalyst for hydrogen production under visible light irradiation

A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations （DFT） and electrochem ical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocat alytic hydrogen production experiments under a visible light irradiation （A〉420 nm） were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3S and Rh was found to be the best one among the tested ones.

Long-Lasting Properties of Rare Earth-Doped Y_2O_2S Phosphors

The aim of this presentation is to report a new result of afterglow materials. The Y 2O 2S∶Ln 3+ (Ln=Sm, Tm) phosphors show bright reddish orange and orange-yellow colors when excited by UV or visible light. The main spectroscopic characterizations of Sm 3+ and Tm 3+ in yttrium oxysulfide and their long-lasting phosphorescence were measured and discussed in this presentation. Their long-lasting phosphorescence can be seen by the naked eyes clearly for about one hour in the dark room after the irradiation light sources were removed. XRD and photoluminescence (PL) spectra as well as the luminance decay were used to characterize these long-lasting phosphorescence phosphors. The results of XRD indicate that the products synthesized through the flux fusion method under 1050 ℃ for 6 h have a good crystallization without any detectable amount of impurity phase. Both the PL spectra and luminance decay results reveal that these phosphors have efficient luminescent and good long-lasting properties. We believe that the experimental data gathered in our present work will be useful in finding some new long-lasting phosphors with different colors.

Synthesis of Y_2O_2S：Eu^（3＋） Phosphor by Microwave Thermal Effectand Its Luminescent Properties

The phosphor Y2O2S:Eu3+ powder crystal has been synthesized by using the microwave thermal method.The data of X-ray powder diffraction showed that the phosphor structure belongs to hexagonal system with lattice parameters a=0.3785 nm,c=0.6590nm.The excitation spectrum of the phosphor is a broad band with peak at λ(ex)= 261 nm.The main emission peak at λ(em)=626nm and the other emission lines peak at 595,617 and 706 nm are assigned to transitions of the Eu3+ respectively.Under 254 nm excitation,the chromatic coordinates of phosphor are x=0.665, y=0.330.The relative luminescent intensity is about 62% compared with the standard phosphor Y2O3:Eu3+.Under 365nm excitation this phosphor gives rise to an intense red light.The phosphor particle size has a medium diameter of 7.3μm.

High performance n^+p-Si/Ti/NiS_xO_y photocathode for photoelectrochemical hydrogen evolution in alkaline solution

Silicon, as a promising semiconductor for fabricating photocathode toward photoelectrochemical hydrogen evolution reaction(PEC-HER), should be improved in light harvesting ability and catalytic kinetics to obtain high PEC performance. Herein, a novel amorphous Nickel Oxysulfide(NiS_xO_y) film is effectively integrated with a Ti protected n^+p-Si micropyramid photocathode by the electrodeposition method. The fabricated n^+p-Si/Ti/Ni SxOyphotocathode exhibits excellent PEC-HER performance with an onset potential of 0.5 V(at J =-0.1 mA/cm^2), a photocurrent density of-26 mA/cm^2 at 0 V vs. RHE, and long term stability of six hours in alkaline solution(pH ≈ 14). The synergy of unique n^+p-Si micropyramid architectures(omnidirectional broadband light harvesting ability), novel amorphous NiS_xO_y catalyst(high HER electrocatalytic activity and good optical transparency) results in the high performance of n^+pSi/Ti/Ni S_xO_y. This work offers a novel strategy for effectively integrating electrocatalysts with semiconductor to design efficient photoelectrode toward PEC water splitting.

Effects of Host Doping on Spectral and Long-Lasting Properties of Sm^(3+)-Doped Y_2O_2S

Gd- or Lu-doped long afterglow red phosphor Y2O2S：Sm^3＋ was synthesized using the high temperature flux fusion method. The obtained phosphors were analyzed using X-ray diffraction to determine the crystal structure, and the phase analyses show that the product is in single phase. The luminescence spectra and decay curve were measured on a Hitachi F-4500 fluorescence spectrophotometer. The decay time was determined on an ST-900PM weak light photometer. The analyses show that host doping of Lu improves both luminescence and decay time of the materials. The concentration of doped Lu and Sm was varied in order to determine the optimal condition and to synthesize the product with the best properties. The mechanism of the long afterglow was also briefly discussed.

Experimental and thermodynamic investigations on MnO-SiO_2-Al_2O_3-MnS system

MnO-SiO_2-Al_2O_3-MnS oxysulfide system has been investigated by experimental phase diagram and activity measurement coupled with thermodynamic modeling.Phase equilibria of the MnO-MnS,MnO-SiO_2-MnS, MnO-Al_2O_3-MnS and MnO-SiO_2-Al_2O_3-MnS systems under low oxygen partial pressure have been experimentally investigated for the temperature range of 1 185 to 1 500℃using equilibration and quenching techniques. Equilibrium phases were analyzed by scanning electron microscope,electron probe X-ray microanalysis(EPMA), and differential thermal analysis(DTA ).Phase diagrams were successfully constructed for the systems investigated.Two ternary compounds in the MnO-SiO_2-MnS system were found.Activities of MnO and MnS in MnO-SiO_2-Al_2O_3-MnS liquid oxysulfide solution from very low sulfur concentration to high sulfur concentration at solid MnS saturation were investigated employing gas/liquid/Pt - Mn alloy under controlled atmosphere at 1 500℃.As X(SiO_2)/(X(MnO) + X(SiO_2)) increases in liquid oxysulfide solution,activity coefficient of MnO decreases while that of MnS increases.As X(AlO_(1.5)) increases,the activity coefficient of MnS increases while no remarkable change was observed for the activity coefficient of MnO.Quantitative analysis of the thermodynamic properties of the oxysulfide solution as well as phase diagram of the system was also earned out by employing the Modified Quasichemical Model in the quadruplet approximation.In view of inclusion utilization for free - cutting steel,it might have an advantage to decrease the Al_2O_3 content and increase the MnO/SiO_2 ratio.

Fast and Low Cost X-Ray Stereoradiography Displayed on a 3D Monitor

Conventional x-ray stereoradiography based on film radiography is not practical due to its inconvenient and time-consuming procedures. In this research, an image viewing system consisted of a 30 cm × 30 cm gadolinium oxy-sulfide (GOS) fluorescent screen and a Cannon 500D digital camera were designed and constructed for real-time and near real-time x-ray imaging. The camera was connected to a laptop computer via USB port to allow remote camera setting and control as well as view image on the computer. The system was tested with x-rays generated from a Rigaku x-ray tube for its response at various camera settings and exposure times. The image brightness increased with increasing of the camera ISO setting and with the exposure time as expected. To test the system performance, two test specimens were radiographed including a video camera and a floppy disk drive as well as two simulated specimens. Each of the test specimens was also radiographed at two positions by moving the specimens approximately 6 cm from the first position. The two radiographs of each specimen were then combined to make an anaglyph image that could be viewed in 3D on a normal LCD or LED monitor by using appropriate color glasses. When the two radiographs were combined to make MPO (multiple object) file format, it could be viewed in 3D on a 3D monitor with or without 3D glasses depending on type of the monitor. The developed system could be conveniently employed for routine inspection of a specimen both in 2D and 3D within a minute.

Template-free Fabrication and Luminescent Characterization of Highly Uniform and Monodisperse Y_2O_2S:Sm^(3+) Hollow Submicrospheres

Well dispersed and homogeneous Y2O2S：Sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （SEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. Luminescence properties of the Y202S：Sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

富氧空位修饰的铋氧硫晶体用于光催化二氧化碳还原转化为甲烷

制备高效光催化剂将二氧化碳还原转化为有价值的化学品,是缓解能源危机和环境污染的有效措施.本论文通过高温焙烧法,制备了富氧空位修饰的Bi_(2)O_(2)S光催化剂,并将其用于可见光驱动的CO_(2)光还原,确定了富氧空位修饰的Bi_(2)O_(2)S光催化剂的最佳制备条件.通过一系列实验及表征,证实了BiOS-OV中丰富氧空位的存在;结合理论计算深入分析了引入的丰富氧空位对Bi_(2)O_(2)S光催化剂的内部电子结构及光化学性能等的影响.深入研究了整个体系中光催化CO_(2)还原反应的具体步骤,旨在揭示丰富氧空位的存在引起CO_(2)光还原性能提高的根本原因.

First Investigation of Nonlinear Optical Oxychalcogenide with Three-Dimensional Anionic Framework and Special Windmill-Like Functional Motifs

Oxychalcogenides have been drawn much attention to be explored as nonlinear optical(NLO)materials in recent years.To date,all the NLO oxychalcogenides crystallize in low dimensional structures.Herein,a new oxysulfide K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) was obtained via three-dimensional(3D){[Ga_(9)O_(2)S_(13)]^(3-)}_(∞)polyanionic framework.As the first oxychalcogenide with 3D NLO-acitve polyanionic framework,K_(2)Ba_(0.5)Ga_(9)O_(2)S_(13) has a wide band gap of 3.72 eV,and exhibits a high laser-induced damage threshold(LIDT,17×AgGaS_(2)).It presents moderate phase-matchable NLO response of 0.5×AgGaS_(2) at 2.1μm and 2×KH_(2)PO_(4) at 1.064μm.The theoretical calculation results indicate that the NLO response is mainly contributed from[Ga(2)S4]unit-built[Ga(2)_(3)S_(10)]windmill-like motif.This work may stimulate the exploration of more NLO oxychalcogenides with balanced performances.