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Influence of Local Cation Order on Electronic Structure and Optical Properties of Cation-Disordered Semiconductor AgBiS_(2)

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Chinese Physics Letters 2024年第10期41卷 61-69页

作者： Xiaoyu Wang Muhammad Faizan Yuhao Fu Kun Zhou Yilin Zhang Xin He David J.singh Lijun Zhang State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China Department of Physics and Astronomy University of MissouriColumbiaMissouri 65211-7010USA

Site disorder exists in some practical semiconductors and can significantly impact their intrinsic properties both beneficially and ***,the uncertain local order and structure pose a challenge for experimental and theoretical ***,it hinders the investigation of the effects of the diverse local atomic environments resulting from the site *** employ the special quasi-random structure method to perform first-principles research on connection between local site disorder and electronic/optical properties,using cationdisordered AgBiS_(2)(rock salt phase)as an *** predict that cation-disordered AgBiS_(2)has a bandgap ranging from 0.6 to 0.8 ev without spin-orbit coupling and that spin-orbit coupling reduces this by approximately 0.3 *** observe the effects of local structural features in the disordered lattice,such as the one-dimensional chain-like aggregation of cations that results in formation of doping energy bands near the band edges,formation and broadening of band-tail states,and the disturbance in the local electrostatic potential,which significantly reduces the bandgap and *** influence of these ordered features on the optical properties is confined to alterations in the bandgap and does not markedly affect the joint density of states or optical *** study provides a research roadmap for exploring the electronic structure of site-disordered semiconductor materials,suggests that the ordered chain-like aggregation of cations is an effective way to regulate the bandgap of AgBiS_(2),and provides insight into how variations in local order associated with processing can affect properties.

关键词： stability. structure ordered

FEA-based Geometrical Modification of Switched reluctance Motor for radial Force reduction

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Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： rani S Jayapragash r School of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

Switched reluctance motors(SrMs)are becoming increasingly popular in the automotive sector owing to their robust ***,SrMs are preferred particularly for ev applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of SrM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the SrM.A geometry-based modification of the SrM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 SrM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the SrM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANSYS to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 SrM radial force modal analysis FEA analysis natural frequencies SrM with windows

Non-thermal atmospheric-pressure positive pulsating corona discharge in degradation of textile dye reactive Blue 19 enhanced by Bi_(2)O_(3) catalyst

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Plasma Science and Technology 2024年第2期26卷 104-113页

作者： Milica PETrOVIC Dragan rADIVOJevIC Sasa rANCev Nena VELINOV Milos KOSTIC Danijela BOJIC Aleksandar BOJIC Department of Chemistry Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia Department of Physics Faculty of Sciences and MathematicsUniversity of NisNis 18000Serbia

In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona *** research focused on the interaction of the plasma-generated species and the catalyst,as well as the role of the catalyst in the degradation *** decomposition of the anthraquinone reactive dye reactive Blue 19(rB 19) was performed in a selfmade reactor ***_(2)O_(3) was prepared by electrodeposition followed by thermal treatment,and characterized by x-ray diffraction,scanning electron microscopy and energy-dispersive xray *** was observed that the catalyst promoted decomposition of plasma-generated H_(2)O_(2) into ·OH radicals,the principal dye-degrading reagent,which further attacked the dye *** catalyst improved the decolorization rate by 2.5 times,the energy yield by 93.4%and total organic carbon removal by 7.1%.Excitation of the catalyst mostly occurred through strikes by plasma-generated reactive ions and radical species from the air,accelerated by the electric field,as well as by fast electrons with an energy of up to 15 ev generated by the streamers reaching the liquid *** strikes transferred the energy to the catalyst and created the electrons and holes,which further reacted with H_(2)O_(2) and water,producing ·OH *** was indentified as the primary role of the catalyst in this *** reactions followed pseudo first-order *** of H_(2)O_(2) and the dye degradation rate increased with increase in the input *** optimal catalyst dose was 500 mg·dm^(-3).The decolorization rate was a little lower in river water compared with that in deionized water due to the side reactions of ·OH radicals with organic matter and inorganic ions dissolved in the river water.

关键词： corona rB 19 Bi_(2)O_(3) catalyst degradation

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina evgenii K.Golubev Maria D.evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Flat-footed Females and Missing Males:A New Genus and Species of Pleciofungivoridae(Diptera:Bibionomorpha)represents the First record of the Family from Mid-Cretaceous Kachin amber

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 541-547页

作者： ZHANG Qingqing Wiesław KrZEMINSKI Jan SevCIK Vladimir BLAGODErOV Agnieszka SOSZYNSKA Kornelia SKIBINSKA Yunnan Key Laboratory for Palaeobiology Institute of PalaeontologyYunnan UniversityKunming 650500China MEC International Joint Laboratory for Palaeobiology and Palaeoenvironment Yunnan UniversityKunming 650500China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Institute of Systematics and evolution of Animals Polish Academy of Sciences52551 KrakówPoland University of Ostrava Faculty of ScienceDepartment of Biology and EcologyChittussiho 10CZ-71000 OstravaCzech Republic National Museums Scotland EdinburghUK Natural History Museum LondonUK University of Lodz Faculty of Biology and Environmental ProtectionDepartment of Invertebrate Zoology and HydrobiologyBanacha 12/1690-237ŁódźPoland

A new genus and species,Cretopleciofungivora simpsoni *** ***.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin ***,this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower *** of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper *** new species has a unique structure of fore tarsus,with lobed and extended tarsal segments Ⅱ to Ⅳ,a feature hitherto known only in a few species of extant *** not particularly rare,the new species is currently known only from female *** reasons for this phenomenon,very unusual in Sciaroidea,are briefly discussed,including parthenogenesis as a potentially plausible hypothesis.

关键词： fungus gnats Sciaroidea Upper Cretaceous Burmese amber swollen tarsomeres

Excellent photoluminescence and electrochemical properties of Sm^(3+) doped Ca_(2)MgSi_(2)O_(7) nanophosphor:Display and electrochemical sensor applications

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Journal of rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： r.B.Basavaraj K.Sureshkumar D.P.Aarti M.B.Madhusudana reddy G.Nagaraju T.ramakrishnappa G.r.Navyashree K.r.Venkatesha Babu K.S.Hemalatha Department of Physics BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials researchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi Department of Physics Govt.Science CollegeBengaluru560001India Department of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase purity of the samples were confirmed by the powder X-ray diffraction(PXrD)*** single-phase tetragonal structure is observed from the PXrD results with no additional impurity *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(DrS)and is found to be in the range of 4.01-5.98 ev.A high resolution scanning electron microscope(SEM)was used to study the morphological behaviour of the ***-like structures are observed from the SEM *** particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm(^(4)G_(5/2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photoluminescent concentration quenching is noticed above 5 mol%Sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.Sm^(3+)incorporated Ca_(2)MgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： Green combustion Photoluminescence Orange-red emission Color purity Sensors rare earths

Mo_(2)P Monolayer as a Superior Electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

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Energy & Environmental Materials 2024年第1期7卷 207-214页

作者： Dongxu Jiao Zhongxu Wang Yuejie Liu Qinghai Cai Jingxiang Zhao Carlos r.Cabrera Zhongfang Chen College of Chemistry and Chemical Engineering and Key Laboratory of Photonic and Electronic Bandgap Materials Ministry of EducationHarbin Normal UniversityHarbin 150025China Modern Experiment Center Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold region Ecological Safety Harbin 150025China Department of Chemistry and Biochemistry The University of Texas at El PasoEl Paso TX 79968USA Department of Chemistry University of Puerto RicoRio Piedras CampusSan JuanPuerto Rico 00931USA

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2)and CO_(2)molecules remains rather ***,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea *** results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic ***,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 ev)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side *** outstanding catalytic activity of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active *** findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

关键词： C-N coupling density functional theory Mo_(2)P monolayer urea synthesis

First-principles calculations to investigate structural,electronic,magnetic,optical and thermodynamic properties of rE_(2)rh_(3)Ge(rE=Pr,Sm)

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Journal of rare Earths 2024年第7期42卷 1385-1393,I0007页

作者： A.Ezaier r.Masrour M.Hamedoun J.Kharbach A.rezzouk A.Hourmatallah N.Benzakour K.Bouslykhane Laboratory of Solid Physics Faculty of Sciences Dhar El MehrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco Equipe de Physique du Solide LaboratoiresLIPIEcole Normale SupérieureBensoudaFèsMorocco

In this paper,we analyzed the physical characteristics of the ternary alloys rE_(2)rh_(3)Ge(rE=Pr and Sm)using the first principles calculation based on functional density theory integrated in the Wien2k *** calculated formation energies of Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge are−5.3827 and−5.2782 ev/atom,respectively,showing that these alloys may exist *** results of the band structure and density of states indicate that all of the compounds tested are magnetic metals,and their magnetism is mostly related to the contribution of Pr and Sm *** total magnetic moments of Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge are 4.07245 and 11.16161μB/f.u,*** parameters such as heat capacity at constant pressure,entropy,Debye temperature,lattice volume,compressibility coefficients,and Grüneisen parameter alloys were calculated using the Gibbs algorithm and studied in depth over a large temperature range of 0-900 *** Debye temperature increases with increasing pressure and decreases with decreasing ***,the Debye temperatures calculated at p=0 GPa and T=300 K are equal to be 342 and 322 K for Pr_(2)rh_(3)Ge and Sm_(2)rh_(3)Ge,*** optical characteristics such as the real and imaginary portions of the dielectric function,the absorption coefficient,the energy-loss function,and the refractive index were investigated and discussed in more depth.

关键词： Magnetic metals Functional density theory Density of states Magnetic moment Optical and thermodynamic properties rare earths

Structural,Transport and Optical Properties of Boron-doped Zinc Oxide Nanocrystalline

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Journal of Materials Science & Technology 2011年第6期27卷 481-488页

作者： Vinod Kumar r.G.singh L.P.Purohit r.M.Mehra Department of Physics Gurukula Kangri University Department of Electronic Science University of Delhi South Campus Maharaja Agrasen College University of Delhi 110 096 India School of Engineering & Technology Sharda University

The paper has reported the structural,transport and optical properties of boron doped zinc oxide（ZnO：B） thin films grown on glass substrate by sol-gel spin coating *** is observed from the analysis of the X-ray diffraction（XrD） results that the crystalline quality of the films is improved with increasing B concentration.A crystallite size of ～17 nm is obtained for B doped films.A minimum resistivity of 7.9×10-4 Ω.cm is obtained at 0.6 at.% of B concentration in the ZnO：B *** and intragrain cluster scattering are found to dominate the scattering mechanism in ZnO：B *** interference pattern in transmittance spectra shows good homogeneity with a transparency of ～88% in the visible *** band gap of the films is increased from 3.24 to 3.35 ev with increasing B *** gap widening is analyzed in terms of Burstein-Moss *** origin of the broad band photoluminescence（PL） spectra is explained in terms of the intragrain cluster scattering.

关键词： Zinc oxide Boron Photoluminescence Intragrain B-M shift