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采用单环微谐振器的光滤波器特性及其局限性

光电子．激光 2003年第1期14卷 12-16页

作者：杨建义江晓清王明华 ZHOU Qing-Jun chen ray t 浙江大学信息与电子工程学系浙江杭州310027 Microelectronics Research Center/Dept.of Electrical and Computer Engineering University of Texas at AustinAustin TX 78758USA

对采用单环微谐振器的光滤波器的特性进行了分析。在给出的传递函数和相关特性公式基础上 ,分析了出 /入环光耦合系数与通带带宽和通带消光比间的关系 ,指出了它们之间、以及与自由谱范围间存在的相互约束 ;分析并给出了单环光滤波器的... 详细信息

对采用单环微谐振器的光滤波器的特性进行了分析。在给出的传递函数和相关特性公式基础上 ,分析了出 /入环光耦合系数与通带带宽和通带消光比间的关系 ,指出了它们之间、以及与自由谱范围间存在的相互约束 ;分析并给出了单环光滤波器的通带带宽比例 ,带宽比例值不依赖于任何器件结构参数 ,是限制单环微谐振器作为实用光滤波器的主要因素 ;分析了存在于微环中光的损耗对单环光滤波器输出的影响 ,小的光损耗即会导致滤波响应的巨大衰减 ,大的光损耗则更是会导致带宽的展宽和带宽比例值的增大。

关键词：光滤波器光波导光微环谐振器传递函数

Efficient Removal of Phosphate from Aqueous Solutions Using Corundum-hollow-spheres Supported Caclined Hydrotalcite Porous thin Films

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Journal of Wuhan University of technology(Materials Science) 2024年第1期39卷 44-49页

作者：刘云才 ZHU chen School of Architecture and Materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHt) thin films. Mg-Al-CO3 hydrotalcite (Ht) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHt thin films were obtained by annealing of the Ht thin films at 500℃for 180 min. their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).the results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. the mechanism of nucleation and growth of the Ht thin films was fitted well with the anion coordination polyhedron growth unit model. to determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. the highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). the adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

Yttrium‐and nitrogen‐doped NiCo phosphide nanosheets for high‐efficiency water electrolysis

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Carbon Energy 2024年第8期6卷 214-231页

作者： Guangliang chen Huiyang Xiang Yingchun Guo Jun Huang Wei chen Zhuoyi chen tongtong Li Kostya(Ken)Ostrikov Department of Materials Engineering Huzhou UniversityHuzhouChina School of Materials Science and Engineering Zhejiang Sci‐Tech UniversityHangzhouChina School of Physics and Electronic Information Gannan Normal UniversityGanzhouChina School of Chemistry and Physics Centre for Materials ScienceCentre for Clean Energy Technologies and PracticesCentre for Waste−Free WorldQueensland University of Technology(QUT)BrisbaneQueenslandAustralia

Engineering high‐performance and low‐cost bifunctional catalysts for H_(2)(hydrogen evolution reaction[HER])and O_(2)(oxygen evolution reaction[OER])evolution under industrial electrocatalytic conditions remains ***,for the first time,we use the stronger electronegativity of a rare‐Earth yttrium ion(Y^(3+))to induce in situ NiCo‐layered double‐hydroxide nanosheets from NiCo foam(NCF)treated by a dielectric barrier discharge plasma NCF(PNCF),and then obtain nitrogen‐doped YNiCo phosphide(N‐YNiCoP/PNCF)after the phosphating process using radiofrequency plasma in *** obtained NYNiCoP/PNCF has a large specific surface area,rich heterointerfaces,and an optimized electronic structure,inducing high electrocatalytic activity in HER(331mV vs.2000mA cm^(−2))and OER(464mV vs.2000mA cm^(−2))reactions in 1MKOH electrolyte.X‐ray absorption spectroscopy and density functional theory quantum chemistry calculations reveal that the coordination number of CoNi decreased with the incorporation of Y atoms,which induce much shorter bonds of Ni and Co ions and promote long‐term stability of N‐YNiCoP in HER and OER under the simulated industrial ***,the CoN‐YP_(5)heterointerface formed by plasma N‐doping is the active center for overall water *** work expands the applications of rare‐Earth elements in engineering bifunctional electrocatalysts and provides a new avenue for designing highperformance transition‐metal‐based catalysts in the renewable energy field.

关键词： overall water splitting plasma etching plasma N‐doping rare‐earth electrocatalyst yttrium incorporation

Multiscale Study on Low temperature Crack Resistance Mechanism of Steel Slag Asphalt Mixture

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Journal of Wuhan University of technology(Materials Science) 2024年第3期39卷 705-715页

作者：白雪峰王岚 chen Xiunan School of Science Inner Mongolia University of TechnologyHohhot 010051China School of Civil Engineering Key Laboratory of Civil Engineering Structure and MechanicsInner Mongolia University of TechnologyHohhot 010051China Inner Mongolia traffic De-sign Institute Co.LtD Hohhot 010050China

the objective of this paper was to study low temperature crack resistance mechanism of steel slag asphalt mixture(SAM).thermal stress restrained specimen test(tSRSt)and three-point bending test were carried out to evaluate the low-temperature crack resistance of SAM and basalt asphalt mixture(BAM).Based on the digital image correlation technique(DIC),the strain field distribution and crack propagation of SAM were analyzed from the microscopic point of view,and a new index,crack length factor(C),was proposed to evaluate the crack resistance of the asphalt *** crystal phase composition and microstructure of steel slag aggregate(SA)and basalt aggregate(BA)were studied by X-ray diffraction(XRD)and scanning electron microscopy(SEM)to explore the low-temperature crack resistance mechanism of *** show that the low-temperature crack resistance of SAM is better than that of BAM;SAM has good integrity and persistent elastic deformation,and its bending failure mode is a hysteretic quasi-brittle failure;the SA surface is evenly distributed with pores and has surface *** has the composition phase of alkaline aggregate-calcite(CaCO3),so it has good adhesion to asphalt,which reveals the mechanism of excellent low-temperature crack resistance of SAM.

关键词： steel slag asphalt mixture ·low-temperature crack resistance ·strain energy density ·XRD SEM

Optimal geometrical configuration and oxidation state of cobalt cations in spinel oxides to promote the performance of Li-O_(2) battery

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Nano Research 2024年第1期17卷 221-227页

作者： Yu Zhang Shuting Zhang Mengwei Yuan Yufeng Li Rong Liu Caiyun Nan chen chen Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China X-ray diffraction Lab Analytical and Testing CenterBeijing Normal UniversityBeijing 100875China

Co_(3)O_(4) is considered as one of promising cathode catalysts for lithium oxygen(Li-O_(2))batteries,which contains both tetrahedral Co^(2+)sites(Co^(2+)td)and octahedral Co^(3+)sites(Co^(3+)Oh).It is important to reveal the effect of optimal geometric configuration and oxidation state of cobalt ion in Co_(3)O_(4) to improve the performance of Li-O_(2) ***,through regulating the synthesis process,Co^(2+)and Co^(3+)sites in Co_(3)O_(4) were replaced with Zn and Al atoms to form materials with a unique Co *** Li-O_(2) batteries based on ZnCo_(2)O_(4) showed longer cycle life than that of CoAl_(2)O_(4),suggesting that in Co_(3)O_(4),the Co^(3+)Oh site is a relatively better geometric configuration than Co^(2+)td site for Li-O_(2) *** calculations revealed that Co^(3+)Oh sites provide higher catalysis activity,regulating the adsorption energy of the intermediate LiO_(2) and accelerating the kinetics of the reaction in batteries,which further leads to the change of the morphology of the discharge product and ultimately improves the electrochemical performance of the batteries.

关键词： lithium oxygen(Li-O_(2))batteries geometrical configuration oxidation state lithium peroxide

Cation-Anion Redox Active Organic Complex for High Performance Aqueous Zinc Ion Battery

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Energy & Environmental Materials 2024年第1期7卷 60-67页

作者： Lilin Zhang Yining chen Zongyuan Jiang Jingwei chen Cong Wei Wenzhuo Wu Shaohui Li Qun Xu School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Institute of Advanced technology Zhengzhou UniversityZhengzhou 450001China School of Materials Science and Engineering Ocean University of China Qingdao 266100China

Organic redox compounds are attractive cathode materials in aqueous zinc-ion batteries owing to their low cost,environmental friendliness,multiple-electron-transfer reactions,and resource ***,the realized energy density is constrained by the limited capacity and low ***,copper-tetracyanoquinodimethane(CutCNQ),an organic charge-transfer complex is evaluated as a zinc-ion battery cathode owing to the good electron acceptation ability in the cyano groups that improves the voltage *** electrochemical activation,electrolyte optimization,and adoption of graphene-based separator,CutCNQ-based aqueous zinc-ion batteries deliver much improved rate performance and cycling stability with anti-self-discharge *** structural evolution of CutCNQ during discharge/charge are investigated by ex situ Fourier transform infra-red(Ft-IR)spectra,ex situ X-ray photoelectron spectroscopy(XPS),and in situ ultraviolet visible spectroscopy(UV-vis),revealing reversible redox reactions in both cuprous cations(Cu^(+))and organic anions(tCNQ^(x-1)),thus delivering a high voltage output of 1.0 V and excellent discharge capacity of 158 mAh g^(-1).the remarkable electrochemical performance in Zn//CutCNQ is ascribed to the strong inductive effect of cyano groups in CutCNQ that elevated the voltage output and the graphene-modified separator that inhibited CutCNQ dissolution and shuttle effect in aqueous electrolytes.

关键词： cathode materials cyano groups electrochemical activation organic charge-transfer complex zinc-ion battery

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian chen Hao-chen Song Lu-Yu Zhong Yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Structure and mechanical properties of windmill palm fiber with different delignification treatments

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Journal of Bioresources and Bioproducts 2024年第1期9卷 102-112页

作者： Changjie chen Pengfei Xu Xinhou Wang Key Laboratory of textile Science&technology(Donghua University) Ministry of EducationCollege of Textiles2999 Renmin North RoadShanghai 201620China Basalt Fiber and Composite Key Laboratory of Sichuan Province Sichuan 635000China College of Mechanical Engineering Donghua UniversityShanghai 201620China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123China Shanghai Composite technology Co.Ltd. Shanghai 201112China

the removal of lignin from natural cellulose fibers is a crucial step in preparing high-performance materials,such as compressed high-toughness *** process can eliminate non-cellulosic impurities,create abundant compressible pores,and expose a greater number of active functional *** this study,biomass waste windmill palm fiber was used as the raw mate-rial to prepare holocellulose fibers through various chemical *** structure,chemical composition,Fourier transform infrared spectroscopy analysis,X-ray diffraction analysis,ther-mal properties,and mechanical properties,particularly fatigue performance,were *** sodium chlorite treated fiber had the highest crystallinity index(61.3%)and the most complete appearance *** sodium sulfite treated fiber had the highest tensile strength(227.34±52.27)*** peroxide treatment removed most of the lignin and hemicellulose,increas-ing the cellulose content to 68.83%±0.65%.However,all the chemical treatments decreased the thermal property of the fibers.

关键词： Windmill palm fiber Delignification treatment Morphonology Mechanical property Fatigue property

the Influence of the Sun and Moon on the Observation of Very High Energy Gamma-ray Sources Using EAS Arrays

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Research in Astronomy and Astrophysics 2024年第6期24卷 245-252页

作者： tao Wen Songzhan chen Benzhong Dai School of Physics and Astronomy Yunnan UniversityKunming 650091China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China tianfu Cosmic ray Research Center Chengdu 610000China

With great advance of ground-based extensive air shower arrays,such as LHAASO and HAWC,many very high energy(VHE)gamma-ray sources have been discovered and are being monitored regardless of the day and the ***,the Sun and Moon would have some impacts on the observation of gamma-ray sources,which have not been taken into account in previous *** this paper,the influence of the Sun and Moon on the observation of very high energy gamma-ray sources when they are near the line of sight of the Sun or Moon is *** tracks of all the known VHE sources are scanned and several VHE sources are found to be very close to the line of sight of the Sun or Moon during some *** absorption of very high energy gamma rays by sunlight is estimated with detailed method and some useful conclusions are *** main influence is the block of the Sun and Moon on gamma rays and the shadow on the cosmic ray *** influence is investigated considering the detector angular resolution and some strategies on data analysis are proposed to avoid the underestimation of the gamma-ray emission.

关键词： astroparticle physics Sun:general methods:observational Sun:UV radiation