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Microvascular alterations of the ocular surface and retina in connective tissue disease-related interstitial lung disease
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作者 Li-Ming Chen Min Kang +12 位作者 Jun-Yi Wang San-Hua Xu Cheng Chen Hong Wei Qian Ling Liang-Qi He Jie Zou Yi-Xin Wang Xu Chen Ping Ying Hui Huang Yi Shao Rui Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第10期1869-1879,共11页
AIM:To examine the disparities in macular retinal vascular density between individuals with connective tissue disease-related interstitial lung disease(CTD-ILD)and healthy controls(HCs)by optical coherence tomography ... AIM:To examine the disparities in macular retinal vascular density between individuals with connective tissue disease-related interstitial lung disease(CTD-ILD)and healthy controls(HCs)by optical coherence tomography angiography(OCTA)and to investigate the changes in microvascular density in abnormal eyes.METHODS:For a retrospective case-control study,a total of 16 patients(32 eyes)diagnosed with CTD-ILD were selected as the ILD group.The 16 healthy volunteers with 32 eyes,matched in terms of age and sex with the patients,were recruited as control group.The macular retina’s superficial retinal layer(SRL)and deep retinal layer(DRL)were examined and scanned using OCTA in each individual eye.The densities of retinal microvascular(MIR),macrovascular(MAR),and total microvascular(TMI)were calculated and compared.Changes in retinal vascular density in the macular region were analyzed using three different segmentation methods:central annuli segmentation method(C1-C6),hemispheric segmentation method[uperior right(SR),superior left(SL),inferior left(IL),and inferior right(IR)],and Early Treatment Diabetic Retinopathy Study(ETDRS)methods[superior(S),inferior(I),left(L),and right(R)].The data were analyzed using Version 9.0 of GraphPad prism and Pearson analysis.RESULTS:The OCTA data demonstrated a statistically significant difference(P<0.05)in macular retinal microvessel density between the two groups.Specifically,in the SRL and DRL analyses,the ILD group exhibited significantly lower surface density of MIR and TMI compared to the HCs group(P<0.05).Furthermore,using the hemispheric segmentation method,the ILD group showed notable reductions in SL,SR,and IL in the superficial retina(P<0.05),as well as marked decreases in SL and IR in the deep retina(P<0.05).Similarly,when employing the ETDRS method,the ILD group displayed substantial drops in superficial retinal S and I(P<0.05),along with notable reductions in deep retinal L,I,and R(P<0.05).In the central annuli segmentation method,the ILD group exhibited a significant decrease in the superficial retinal C2-4 region(P<0.05),whereas the deep retina showed a notable reduction in the C3-5 region(P<0.05).Additionally,there was an observed higher positive likelihood ratio in the superficial SR region and deep MIR.Furthermore,there was a negative correlation between conjunctival vascular density and both deep and superficial retinal TMI(P<0.001).CONCLUSION:Patients with CTD-ILD exhibits a significantly higher conjunctival vascular density compared to the HCs group.Conversely,their fundus retinal microvascular density is significantly lower.Furthermore,CTD-ILD patients display notably lower superficial and deep retinal vascular density in comparison to the HCs group.The inverse correlation between conjunctival vascular density and both superficial and deep retinal TMI suggests that detecting subtle changes in ocular microcirculation could potentially serve as an early diagnostic indicator for connective tissue diseases,thereby enhancing disease management. 展开更多
关键词 connective tissue disease‑related interstitial lung disease optical coherence tomography angiography microvessel density ocular surface RETINA
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Dual-channel fiber-optic surface plasmon resonance sensor with cascaded coaxial dual-waveguide D-type structure and microsphere structure 被引量:1
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作者 李玲玲 魏勇 +4 位作者 刘春兰 任卓 周爱 刘志海 张羽 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期201-208,共8页
To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-typ... To address the restriction of fiber-optic surface plasmon resonance(SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-type structure and microsphere structure is proposed in this paper. The fiber sidepolishing technique converts the coaxial dual-waveguide fiber into a D-type one, and the evanescent wave in the ring core leaks, generating a D-type sensing region;the fiber optic fused ball push technology converts the coaxial dual waveguides into microspheres, and the stimulated cladding mode evanescent wave leaks, producing the microsphere sensing region. By injecting light into the coaxial dual-waveguide middle core alone, the sensor can realize single-stage sensing in the microsphere sensing area;it can also realize dual-channel sensing in the D-type sensing area and microsphere sensing area by injecting light into the ring core. The refractive index measurement ranges for the two channels are 1.333–1.365 and 1.375–1.405, respectively, with detection sensitivities of 981.56 nm/RIU and 4138 nm/RIU. The sensor combines wavelength division multiplexing and space division multiplexing technologies, presenting a novel research concept for multi-channel fiber SPR sensors. 展开更多
关键词 coaxial dual-waveguide optical fiber D structure optical fiber microsphere structure dual-channel fiber-optic surface plasmon resonance(SPR)sensor
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Optical Surface Monitoring系统跟踪运动靶区的位置精度和剂量精度验证 被引量:3
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作者 靳怀志 石俊田 +1 位作者 戴振晖 王学涛 《中国医学物理学杂志》 CSCD 2019年第6期641-646,共6页
目的:评估Optical Surface Monitoring System(OSMS)测量靶区运动的几何精度和使用OSMS跟踪运动靶区放疗时的剂量精度。方法:①分别使用OSMS与锥形束CT监测腹部模体的位置,通过移动治疗床使模体产生位移和旋转,对比二者对模体位置的测... 目的:评估Optical Surface Monitoring System(OSMS)测量靶区运动的几何精度和使用OSMS跟踪运动靶区放疗时的剂量精度。方法:①分别使用OSMS与锥形束CT监测腹部模体的位置,通过移动治疗床使模体产生位移和旋转,对比二者对模体位置的测量结果;②用呼吸运动平台搭载MatriXX二维电离室阵列,测量不同跟踪阈值时模体内相对剂量,分别与计划剂量分布对比,分析不同跟踪阈值时计划验证的gamma通过率。结果:OSMS和锥形束CT系统对模体平移和旋转预设偏移的测量结果差异很小,使用OSMS门控技术时OSMS的阈值越小gamma通过率越高,相对剂量分布与计划剂量的一致性也越好。结论:OSMS系统对模体表面位置监测精度高,可以应用到实际放射治疗的辅助摆位。使用OSMS门控技术跟踪运动靶区可以提高靶区的剂量精度,而且对患者不附加任何电离辐射,适合应用于分次间的辅助摆位和分次内的靶区跟踪。 展开更多
关键词 optical surface MONITORING SYSTEM 锥形束CT 运动跟踪 模体 放射剂量 位置精度
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Surface roughness prediction model in ultrasonic vibration assisted grinding of BK7 optical glass 被引量:9
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作者 ZHAO Pei-yi ZHOU Ming +1 位作者 ZHANG Yuan-jing QIAO Guo-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期277-286,共10页
Pre-knowledge of machined surface roughness is the key to improve whole machining efficiency and meanwhile reduce the expenditure in machining optical glass components.In order to predict the surface roughness in ultr... Pre-knowledge of machined surface roughness is the key to improve whole machining efficiency and meanwhile reduce the expenditure in machining optical glass components.In order to predict the surface roughness in ultrasonic vibration assisted grinding of brittle materials,the surface morphologies of grinding wheel were obtained firstly in the present work,the grinding wheel model was developed and the abrasive trajectories in ultrasonic vibration assisted grinding were also investigated,the theoretical model for surface roughness was developed based on the above analysis.The prediction model was developed by using Gaussian processing regression(GPR)due to the influence of brittle fracture on machined surface roughness.In order to validate both the proposed theoretical and GPR models,32sets of experiments of ultrasonic vibration assisted grinding of BK7optical glass were carried out.Experimental results show that the average relative errors of the theoretical model and GPR prediction model are13.11%and8.12%,respectively.The GPR prediction results can match well with the experimental results. 展开更多
关键词 surface roughness prediction model ultrasonic vibration optical glass GPR regression
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Position-resolved Surface Characterization and Nanofabrication Using an Optical Microscope Combined with a Nanopipette/Quartz Tuning Fork Atomic Force Microscope 被引量:2
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作者 Sangmin An Baekman Sung +6 位作者 Haneol Noh Corey Stambaugh Soyoung Kwon Kunyoung Lee Bongsu Kim Qhwan Kim Wonho Jhe 《Nano-Micro Letters》 SCIE EI CAS 2014年第1期70-79,共10页
In this work, we introduce position-resolved surface characterization and nanofabrication using an optical microscope(OM) combined with a nanopipette-based quartz tuning fork atomic force microscope(nanopipette/QTF-AF... In this work, we introduce position-resolved surface characterization and nanofabrication using an optical microscope(OM) combined with a nanopipette-based quartz tuning fork atomic force microscope(nanopipette/QTF-AFM) system. This system is used to accurately determine substrate position and nanoscale phenomena under ambient conditions. Solutions consisting of 5 nm Au nanoparticles, nanowires, and polydimethylsiloxane(PDMS) are deposited onto the substrate through the nano/microaperture of a pulled pipette. Nano/microscale patterning is performed using a nanopipette/QTF-AFM, while position is resolved by monitoring the substrate with a custom OM. With this tool, one can perform surface characterization(force spectroscopy/microscopy) using the quartz tuning fork(QTF) sensor. Nanofabrication is achieved by accurately positioning target materials on the surface, and on-demand delivery and patterning of various solutions for molecular architecture. 展开更多
关键词 surface characterization Nanopipette QTF-AFM optical microscope
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The determination of the thickness and the optical dispersion property of gold film using spectroscopy of a surface plasmon in the frequency domain 被引量:2
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作者 黄妍 叶红安 +1 位作者 李松权 窦寅丰 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期419-425,共7页
We propose to use wavelength modulation approach,i.e.,the spectroscopy of a surface plasmon in the frequency domain,to characterize the optical dispersion property of gold film.Using this method,we determine the dispe... We propose to use wavelength modulation approach,i.e.,the spectroscopy of a surface plasmon in the frequency domain,to characterize the optical dispersion property of gold film.Using this method,we determine the dispersion relationship of gold film in a wavelength range from 537.12 nm to 905.52 nm,and our results accord well with the reported results by other authors.This method is particularly suited for studying the optical dispersion properties of thin metal films,because a series of dielectric constants over a wide spectral range can be determined simultaneously via only a single scan of the incident angle,thereby avoiding the repeated measurements required when using the angular modulation approach. 展开更多
关键词 surface plasmon polaritons(SPPs) optical dispersion property gold film
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Polar interface and surface optical vibration spectra in multi-layer wurtzite quantum wires: transfer matrix method 被引量:1
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作者 张立 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期1101-1109,共9页
The polar interface optical (IO) and surface optical (SO) phonon modes and the corresponding Froehlich electron phonon-interaction Hamiltonian in a freestanding multi-layer wurtzite cylindrical quantum wire (QWR... The polar interface optical (IO) and surface optical (SO) phonon modes and the corresponding Froehlich electron phonon-interaction Hamiltonian in a freestanding multi-layer wurtzite cylindrical quantum wire (QWR) are derived and studied by employing the transfer matrix method in the dielectric continuum approximation and Loudon's uniaxial crystal model. A numerical calculation of a freestanding wurtzite GaN/AlN QWR is performed. The results reveal that for a relatively large azimuthal quantum number m or wave-number kz in the free z-direction, there exist two branches of IO phonon modes localized at the interface, and only one branch of SO mode localized at the surface in the system. The degenerating behaviours of the IO and SO phonon modes in the wurtzite QWR have also been clearly observed for a small kz or m. The limiting frequency properties of the IO and SO modes for large kz and m have been explained reasonably from the mathematical and physical viewpoints. The calculations of electron-phonon coupling functions show that the high-frequency IO phonon branch and SO mode play a more important role in the electron phonon interaction. 展开更多
关键词 interface and surface optical phonons multi-layer cylindrical heterostructures wurtzite quantum wires
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Research on automatic inspection system for defects on precise optical surface based on machine vision 被引量:1
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作者 王雪 《Journal of Chongqing University》 CAS 2006年第2期89-93,共5页
In manufacture of precise optical products, it is important to inspect and classify the potential defects existing on the products’ surfaces after precise machining in order to obtain high quality in both functionali... In manufacture of precise optical products, it is important to inspect and classify the potential defects existing on the products’ surfaces after precise machining in order to obtain high quality in both functionality and aesthetics. The existing methods for detecting and classifying defects all are low accuracy or efficiency or high cost in inspection process. In this paper, a new inspection system based on machine vision has been introduced, which uses automatic focusing and image mosaic technologies to rapidly acquire distinct surface image, and employs Case-Based Reasoning(CBR)method in defects classification. A modificatory fuzzy similarity algorithm in CBR has been adopted for more quick and robust need of pattern recognition in practice inspection. Experiments show that the system can inspect surface diameter of 500mm in half an hour with resolving power of 0.8μm diameter according to digs or 0.5μm transverse width according to scratches. The proposed inspection principles and methods not only have meet manufacturing requirements of precise optical products, but also have great potential applications in other fields of precise surface inspection. 展开更多
关键词 optical surface defect inspection: machine vision CBR
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3D automatic segmentation method for retinal optical coherence tomography volume data using boundary surface enhancement 被引量:1
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作者 Yankui Sun Tian Zhang +1 位作者 Yue Zhao Yufan He 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2016年第2期41-58,共18页
With the introduction of spectral-domain optical coherence tomography(SD-OCT),much larger image datasets are routinely acquired compared to what was possible using the previous generation of time-domain OCT.Thus,there... With the introduction of spectral-domain optical coherence tomography(SD-OCT),much larger image datasets are routinely acquired compared to what was possible using the previous generation of time-domain OCT.Thus,there is a critical need for the development of three-dimensional(3D)segmentation methods for processing these data.We present here a novel 3D automatic segmentation method for retinal OCT volume data.Brie°y,to segment a boundary surface,two OCT volume datasets are obtained by using a 3D smoothingfilter and a 3D differentialfilter.Their linear combination is then calculated to generate new volume data with an enhanced boundary surface,where pixel intensity,boundary position information,and intensity changes on both sides of the boundary surface are used simultaneously.Next,preliminary discrete boundary points are detected from the A-Scans of the volume data.Finally,surface smoothness constraints and a dynamic threshold are applied to obtain a smoothed boundary surface by correcting a small number of error points.Our method can extract retinal layer boundary surfaces sequentially with a decreasing search region of volume data.We performed automatic segmentation on eight human OCT volume datasets acquired from a commercial Spectralis OCT system,where each volume of datasets contains 97 OCT B-Scan images with a resolution of 496512(each B-Scan comprising 512 A-Scans containing 496 pixels);experimental results show that this method can accurately segment seven layer boundary surfaces in normal as well as some abnormal eyes. 展开更多
关键词 optical coherence tomography boundary surface enhancement retinal layer segmentation OCT volume data
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Investigation on the Effect of Film Thickness on the Surface Morphology, Electrical and Optical Properties of E-Beam Deposited Indium Tin Oxide (ITO) Thin Film 被引量:1
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作者 Golam Saklayen Shahinul Islam +1 位作者 Ferdous Rahman Abu Bakar Ismail 《Advances in Materials Physics and Chemistry》 2014年第10期194-202,共9页
The following article has been retracted due to the fact that the authors practise fraud. The scientific community takes a very strong view on this matter, and the Advances in Materials Physics and Chemistry treats al... The following article has been retracted due to the fact that the authors practise fraud. The scientific community takes a very strong view on this matter, and the Advances in Materials Physics and Chemistry treats all unethical behavior seriously. This paper published in Vol. 4 No. 10 194-202, 2014 has been removed from this site. ? Title: Investigation on the Effect of Film Thickness on the Surface Morphology, Electrical and Optical Properties of E-Beam Deposited Indium Tin Oxide (ITO) Thin Film ? Authors: Golam Saklayen, Shahinul Islam, Ferdous Rahman, Abu Bakar 展开更多
关键词 E-BEAM Deposition surface Morphology Thin Films EDX ATOMIC Force MICROSCOPY SEM ANNEALING Electrical and optical Properties
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Impact of Surface Passivation on the Electronic Structure and Optical Properties of the Si1-xGex Nanowires 被引量:1
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作者 赖信 张析 +1 位作者 张依兮 向钢 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第2期119-122,共4页
The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires (NWs) passivated with different functional groups (-H, -F and-OH) are investigated by using first-principles calculations. ... The electronic structures and optical properties of the [llO]-oriented Sil-xGex nanowires (NWs) passivated with different functional groups (-H, -F and-OH) are investigated by using first-principles calculations. The results show that surface passivation influences the characteristics of electronic band structures significantly: the band gap widths and types (direct or indirect) of the Si1-xGe, NWs with different terminators show complex and robust variations, and the effective masses of the electrons in the NWs can be modulated dramatically by the terminators. The study of optical absorption shows that the main peaks of the parallel polarization component of Si1-x Gex NWs passivated with the functional groups exhibit prominent changes both in height and position, and are red-shifted with respect to those of corresponding pure Si NWs, indicating the importance of both the terminators and Ge concentrations. Our results demonstrate that the electronic and optical properties of Si1-xGex NWs can be tuned by utilizing selected functional groups as well as particular Ge concentrations for customizing purposes. 展开更多
关键词 110 OH x)Ge_x Nanowires Impact of surface Passivation on the Electronic Structure and optical Properties of the Si Ge
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Optical Surface Tilt Measurement with Sub-Second Accuracy
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作者 孙东松 邓桦 +2 位作者 乔立杰 李助朋 蔡喜平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期12-15,共4页
This paper presents a coherent resolved heterodyne interferometer used for recognition of surfaces of optical systems with resort to a short coherence length light source and a position sensitive detection(PSD), and i... This paper presents a coherent resolved heterodyne interferometer used for recognition of surfaces of optical systems with resort to a short coherence length light source and a position sensitive detection(PSD), and its special features of surface sensitivity, high resolution and short measuring time. 展开更多
关键词 HETERODYNE INTERFEROMETER position sensitive detector optical surface mesaurement
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Band structure,Fermi surface,elastic,thermodynamic,and optical properties of AlZr3,AlCu3,and AlCu2Zr:First-principles study
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作者 Parvin R Parvin F +1 位作者 Ali M S Islam A K M A 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期103-112,共10页
The electronic properties(Fermi surface,band structure,and density of states(DOS)) of Al-based alloys AlM3(M=Zr and Cu) and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method w... The electronic properties(Fermi surface,band structure,and density of states(DOS)) of Al-based alloys AlM3(M=Zr and Cu) and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method within the generalized gradient approximation(GGA).The structural parameters and elastic constants are evaluated and compared with other available data.Also,the pressure dependences of mechanical properties of the compounds are studied.The temperature dependence of adiabatic bulk modulus,Debye temperature,specific heat,thermal expansion coefficient,entropy,and internal energy are all obtained for the first time through quasi-harmonic Debye model with phononic effects for T = 0 K-100 K.The parameters of optical properties(dielectric functions,refractive index,extinction coefficient,absorption spectrum,conductivity,energy-loss spectrum,and reflectivity) of the compounds are calculated and discussed for the first time.The reflectivities of the materials are quite high in the IR-visible-UV region up to ~ 15 eV,showing that they promise to be good coating materials to avoid solar heating.Some of the properties are also compared with those of the Al-based Ni3 Al compound. 展开更多
关键词 first principle calculations Fermi surface elastic moduli ENTROPY and internal energy optical properties
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Difference scattering field properties between periodic defect particles and three-dimensional slightly rough optical surface
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作者 葛城显 吴振森 +1 位作者 白靖 巩蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期140-147,共8页
Based on the practical situation of nondestructive examination, the calculation model of the composite scattering is established by using a three-dimensional half-space finite difference time domain, and the Monte Car... Based on the practical situation of nondestructive examination, the calculation model of the composite scattering is established by using a three-dimensional half-space finite difference time domain, and the Monte Carlo method is used to solve the problem of the optical surface with roughness in the proposed scheme. Moreover, the defect particles are observed as periodic particles for a more complex situation. In order to obtain the scattering contribution of defects inside the optical surface, a difference radar cross section is added into the model to analyze the selected calculations on the effects of numbers, separation distances, different depths and different materials of defects. The effects of different incident angles are also discussed. The numerical results are analyzed in detail to demonstrate the best position to find the defects in the optical surface by detecting in steps of a fixed degree for the incident angle. 展开更多
关键词 light scattering difference scattering field periodic particles rough optical surface
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Electronic, optical properties, surface energies and work functions of Ag_8SnS_6: First-principles method
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作者 卢春林 张林 +2 位作者 张云望 刘慎业 梅杨 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期477-483,共7页
Ternary metal chalcogenide semiconductor Ag8 Sn S6, which is an efficient photocatalyst under visible light radiation,is studied by plane-wave pseudopotential density functional theory. After geometry optimization, th... Ternary metal chalcogenide semiconductor Ag8 Sn S6, which is an efficient photocatalyst under visible light radiation,is studied by plane-wave pseudopotential density functional theory. After geometry optimization, the electronic and optical properties are studied. A scissor operator value of 0.81 e V is introduced to overcome the underestimation of the calculation band gaps. The contribution of different bands is analyzed by virtue of total and partial density of states. Furthermore, in order to understand the optical properties of Ag8 Sn S6, the dielectric function, absorption coefficient, and refractive index are also performed in the energy range from 0 to 11 e V. The absorption spectrum indicates that Ag8 Sn S6has a good absorbency in visible light area. Surface energies and work functions of(411),(4 13),(21 1), and(112) orientations have been calculated. These results reveal the reason for an outstanding photocatalytic activity of Ag8 Sn S6. 展开更多
关键词 density functional theory Ag8Sn S6 optical properties surface energy
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The Diagnosis of Plasma Parameters in Surface Alloying Technique by Optical Emission Spectrometry
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作者 付亚波 张跃飞 +4 位作者 陈强 张广秋 高原 王建忠 隗晓云 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第4期461-463,共3页
Electron density (Ne) in a glow discharge plasma for the surface alloying technique is diagnosed by optical emission spectrometry (OES). With CH4 as the feeding gas, Ne is obtained by comparing the Hβ spectrum ac... Electron density (Ne) in a glow discharge plasma for the surface alloying technique is diagnosed by optical emission spectrometry (OES). With CH4 as the feeding gas, Ne is obtained by comparing the Hβ spectrum according to the Stark broadening effect. It is noticed that Ne varies with the working pressures (30 Pa to 70 Pa) and cathode voltages (500 V to 1000 V), respectively. Due to an abnormal glow discharge, Ne is between 1. 71 × 10^15 /cm^3 to 6.64 × 10^15 /cm^3 and increases rapidly with working gas pressures and cathode voltages. The results show that OES is a useful method to measure the plasma parameters in a surface alloying glow discharge plasma. 展开更多
关键词 surface alloying technique optical emission spectrometry electron density
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Surface defect gap solitons in two-dimensional optical lattices
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作者 孟云吉 刘友文 唐宇煌 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期314-319,共6页
We investigate the existence and stability of surface defect gap solitons at an interface between a defect in a two-dimensional optical lattice and a uniform saturable Kerr nonlinear medium. The surface defect embedde... We investigate the existence and stability of surface defect gap solitons at an interface between a defect in a two-dimensional optical lattice and a uniform saturable Kerr nonlinear medium. The surface defect embedded in the two-dimensional optical lattice gives rise to some unique properties. It is interestingly found that for the negative defect, stable surface defect gap solitons can exist both in the semi-infinite gap and in the first gap. The deeper the negative defect, the narrower the stable region in the semi-infinite gap will be. For a positive defect, the surface defect gap solitons exist only in the semi-infinite gap and the stable region localizes in a low power region. 展开更多
关键词 surface defect gap soliton optical lattice saturable Kerr nonlinear media
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Influence on Multimode Rectangular Optical Waveguide Propagation Loss by Surface Roughness
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作者 Chuanlu Deng Li Zhao +3 位作者 Zhe Liu Nana Jia Fufei Pang Tingyun Wang 《ZTE Communications》 2014年第4期49-53,共5页
Optical scattering loss coefficient of muhimode rectangular waveguide is analyzed in this work. First, the effective refrac tive index and the mode field distribution of waveguide modes are obtained using the Marcatil... Optical scattering loss coefficient of muhimode rectangular waveguide is analyzed in this work. First, the effective refrac tive index and the mode field distribution of waveguide modes are obtained using the Marcatili method. The influence on scattering loss coefficient by waveguide surface roughness is then analyzed. Finally, the mode coupling efficiency for the SMFOpticalWaveguide (SOW) structure and MMFOptical Waveguide (MOW) structure are presented. The total scatter ing loss coefficient depends on modes scattering loss coeffi cients and the mode coupling efficiency between fiber and waveguide. The simulation results show that the total scatter ing loss coefficient for the MOW structure is affected more strongly by surface roughness than that for the SOW struc ture. The total scattering loss coefficient of waveguide decreas es from 3.97 x 10^-2 dB/cm to 2.96 x 10^-4 dB/cm for the SOW structure and from 5.24 - 10^-2 dB/cm to 4.7 x 10^-4 dB/ cm for the MOW structure when surface roughness is from 300nm to 20nm and waveguide length is 100cm. 展开更多
关键词 optical interconnect surface roughness optical waveguide scattering loss coefficient
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SYNTHESIS, SURFACE POTENTIAL AND NONLINEAR OPTICAL PROPERTIES OF NEW AMPHIPHILIC PORPHYRINS
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作者 Xue Qun ZHANG Dong XIAO +2 位作者 Yu WEI (Laboratory of molecular and biomolecular electronics,Southeast University, Nanjing, 210018)Xuan Jie WU Gui Guang XIONG (Chemistry Department, Wuhan University,Wuhan,430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第6期541-542,共2页
A new kind of amphiphilic porphyrin containing only one carboxyl on the β point of porphyrin ring was synthesized. The surface potential and SHG (Second Harmonic Generation) efficiency of monolayer were measured and ... A new kind of amphiphilic porphyrin containing only one carboxyl on the β point of porphyrin ring was synthesized. The surface potential and SHG (Second Harmonic Generation) efficiency of monolayer were measured and the relationship between the surface potential,SHG and the structure of molecule was discussed. 展开更多
关键词 surface AND NEW NONLINEAR OF optical PORPHYRINS POTENTIAL PROPERTIES AMPHIPHILIC
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Volume added surface barrier discharge plasma excited by bipolar nanosecond pulse power in atmospheric air: optical emission spectra influenced by gap distance
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作者 Zilu ZHAO Dezheng YANG +3 位作者 Wenchun WANG Hao YUAN Li ZHANG Sen WANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第11期84-89,共6页
In this paper, volume barrier discharge with different gap distances is added on the discharge border of high-voltage electrode of annular surface barrier discharge for generating volume added surface barrier dischar... In this paper, volume barrier discharge with different gap distances is added on the discharge border of high-voltage electrode of annular surface barrier discharge for generating volume added surface barrier discharge (V-SBD) excited by bipolar nanosecond high-voltage pulse power in atmospheric air. The excited V-SBDs consist of surface barrier discharge (d = 0 mm) and volume added surface barrier discharges (d = 2 mm and 3 mm). The optical emission spectra are recorded for calculating emission intensities of N2 (C3 ∏u → B3∏g) and N2+ (B2 ∑u+ → X2 ∑g+), and simulating rotational and vibrational temperatures. The influences of gap distance of V-SBD on emission intensity and plasma temperature are also investigated and analyzed. The results show that d = 0 mm structure can excite the largest emission intensity of N2 (C3 ∏u → B3 ∏g), while the existence of volume barrier discharge can delay the occurrence of the peak value of the emission intensity ratio of N2 + (B2 ∑u+ → X2 ∑+g)/N2 (C3 ∏u → B3 ∏g) during the rising period of the applied voltage pulse and weaken it during the end period. The increasing factor of emission intensity is effected by the pulse repetition rate. The d = 3 mm structure has the highest threshold voltage while it can maintain more emission intensity of N2 (C3 ∏u→ B3∏g) than that of d = 2 mm structure. The structure of d = 2 mm can maintain more increasing factor than that of the d = 3 mm structure with varying pulse repetition rate. Besides, the rotational temperatures of three V-SBD structures are slightly affected when the gap distance and pulse repetition rate vary. The vibrational temperatures have decaying tendencies of all three structures with the increasing pulse repetition rate. 展开更多
关键词 surface barrier discharge (SBD) volume barrier discharge (VBD) nanosecond pulsed discharge optical emission spectra atmospheric discharge
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