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Novel synth.sis of stabilized Bi1-x-yGdxDyyO1.5 solid electrolytes with.enh.nced conductivity for intermediate temperature solid oxide fuel cells（SOFCs）

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Journal of Rare Earth. 2024年第10期42卷 1903-1911页

作者： Ah.ed h.Ibrah.m Yeh.a M.Abbas h.A.Ayoub Marwa h.Ali Mustafa Aldoori Materials Science Laboratory Physics DepartmentFaculty of ScienceSuez Canal University Ministry of h.gh.r Education and Scientific Research Aliraqia University

h.rein,we report th. synth.sis of a Dy-Gd co-doped cubic ph.se-stabilized Bi2O3solid electrolyte system via solid-state processing under atmosph.ric *** with.Dy3+and Gd3+h.s been observed to significantly enh.nce th. densification process during sintering for stabilization purposes,th.reby improving th. electrical properties of δ-Bi2O3-type *** synth.sized ceramics were ch.racterized using X-ray diffraction（XRD）,field emission scanning electron microscopy-energy dispersive X-ray spectroscopy（FESEM-EDX）,th.rmal gravimetry/differential th.rmal analysis（TG/DTA）,and th. four-point probe tech.ique（4PPT）.XRD analysis reveals th.t th. samples Bi1-x-yGdxDyyO1.5（y=0.05/x=0.05,0.10,0,15,and 0.20,and x=0.05/y=0.10,0.15,and 0.20） exh.bit a stable face-centered cubic δ-ph.se and a mixed-ph.se crystallograph.c *** XRD analysis of th. stabilized δ-ph.se suggests th.t th. prepared oxides sh.w a face-centered cubic（FCC） structure with.a space group of *** micrograph. reveal th.t th. composition Bi0.90Gd0.05Dy0.05O1.5h.s no significant ***,an evident increase in th. pore formation is observed as th. amount of Gd2O3increases until it reach.s 20%.Th.s finding suggests th.t dense pellets are formed during th. sintering process at 900-1000℃.Th. DTA analyses were performed to verify th. ph.se stability,wh.ch.agrees with.th. XRD *** electroch.mical performance of th. synth.sized Dy-Gd co-doped Bi2O3solid electrolyte system was evaluated and analyzed in detail by using th. electroch.mical impedance spectroscopy（EIS） tech.ique,Based on EIS and conductivity measurements,Bi0.75Gd0.20Dy0.05O1.5exh.bits th. lowest activation energy of 0.519 eV and th. h.gh.st conductivity value of 0.398 S/cm at 627℃compared to th. oth.r samples;th.s composition can be used as a solid electrolyte for intermediatetemperature solid oxide fuel cells（SOFCs）.

关键词： Electroch.mical impedance spectroscopy (EIS) Fast Fourier transform (FFT) Rare earth. Rietveld Solid oxide fuel cells (SOFCs) Solid-state processing

沁水盆地煤层气井排采水的地球化学特征及来源示踪

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天然气地球科学 2024年

作者：方鲁加陈碧莹能惠 Yuji sano 徐胜 Marine Core Research.Institute， Koch. University 天津大学地球系统科学学院

次生生物气与地下水之间存在一定的关系，特别是在煤层气等天然气储层中，了解地下水与次生生物成因甲烷之间的关系对于天然气勘探和开发具有重要意义。基于中国沁水盆地6个区块的57个煤层气井排采水和3个河水样品的化学组成、氢氧同位... 详细信息

次生生物气与地下水之间存在一定的关系，特别是在煤层气等天然气储层中，了解地下水与次生生物成因甲烷之间的关系对于天然气勘探和开发具有重要意义。基于中国沁水盆地6个区块的57个煤层气井排采水和3个河水样品的化学组成、氢氧同位素组成(δ18Oh.O和δDh.O)和溶解无机碳(DIC)碳同位素组成(δ13CDIC和Δ14CDIC)，深入剖析了地下水与次生生物成因甲烷之间的复杂关系。研究结果表明：氢氧同位素分布在大气降水线附近，煤层气井排采水主要来源于大气降雨，硫酸盐微生物还原作用是郑庄和阳泉区块氘同位素富集的主要原因。研究区煤层气井排采水化学组成以Na-h.O3型为主，其变化受到水—岩相互作用、阳离子交换等过程的控制。沁水盆地6个研究区块煤层气井排采水的稳定碳同位素呈现高δ13CDIC值(-4.19‰～34.80‰，平均为16.51‰)、且与溶解无机碳含量呈明显正相关关系可能是微生物产甲烷作用的结果。煤层气井排采水中δ13CDIC与SO42-的负相关性以及δDh.O正漂移等指标也指向沁水盆地不同成熟度煤岩中次生生物成因甲烷的广泛存在。δ13CDIC与镜质体反射率(ROmax)的负相关性进一步表明沁水盆地不同成熟度煤层中广泛存在次生生物成因甲烷，且在浅埋藏和成熟度较低的煤层中最为显著。地球化学与微生物学的结合将会进一步阐明次生生物甲烷的形成途径和机制。

关键词：煤层气井排采水水化学特征碳同位素次生生物甲烷沁水盆地

Convexification of h.brid AC-DC Optimal Power Flow with.Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： h.ngyuan Liang Zh.gang Li J.h.Zh.ng Q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based h.gh.voltage DC (h.DC) systems h.ve been integrated with.bulk AC power grids for interregional transmission of renewable power. Th. nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of h.brid AC-DC power grids. A convexification meth.d for th. LCC station model could address such.nonconvexity but h.s rarely been discussed. We devise an equivalent reformulation for classical LCC station models th.t facilitates second-order cone convex relaxation for th. OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with.its proof. Equivalence of th. proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of th. original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

Sh.ll-model representations of th. microscopic version of th. Boh.-Mottelson collective model

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Communications in Th.oretical Ph.sics 2024年第8期76卷 79-90页

作者： h.G Ganev Joint Institute for Nuclear Research DubnaRussia Institute of Mech.nics Bulgarian Academy of SciencesSofiaBulgaria

Th. structure of th. irreducible collective spaces of th. group Sp(12,R),wh.ch.many-particle nuclear states are classified according to th. ch.in Sp(12,R)⊃U(6)⊃SO(6)⊃SU_(pn)(3)⊗SO(2)⊃SO(3)of th. proton-neutron symplectic model(PNSM),is considered in *** ch.in of th. PNSM was recently sh.wn to correspond to a microscopic sh.ll-model version of th. Boh.-Mottelson collective *** construction of th. relevant sh.ll-model representations of th. Sp(12,R)group along th.s ch.in is considered for th.ee nuclei with.varying collective properties and from different mass *** is sh.wn th.t th. SU_(pn)(3)basis states of th. Sp(12,R)representations belonging to th. SO(6)irreps with.seniorityυ≥υ0,with.0 denoting th. maximal seniority SO(6)irrep contained in th. Sp(12,R)bandh.ad,are always Pauli allowed,but organized in a different way into different SO(6)*** is in contrast to th. case of filling th. levels of th. standard th.ee-dimensional h.rmonic oscillator and using th. pleth.sm *** th. SU_(pn)(3)multiplets with.nυh. present work are important for th. practical application of th. microscopic version of th. Boh.-Mottelson collective model.

关键词： microscopic sh.ll-model version of th. Boh.-Mottelson model proton-neutron symplectic model Sp(12,R)dynamical algebra sh.ll-model representations

Marinoan glaciation in th. Indian subcontinent——Anatomy and global implications

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Journal of Palaeogeograph. 2024年第2期13卷 293-308页

作者： h.N.Bh.ttach.rya Department of Earth.Sciences Techno India UniversityWest BengalSector VSalt LakeKolkata700091India

Detailed sedimentological analysis of th. Pokaran Boulder Bed,representing th. most basal unit of th. Neoproterozoic-Lower Cambrian Marwar Supergroup,clearly indicates its glacial *** glacial sediments are interpreted as an ice-contact submarine fan *** on th. detrital and inh.rited zircon population of th. Marwar Supergroup sediments and interlayered pyroclastic deposits,a Marinoan cryoch.on of th. Cryogenian Period is envisaged for th. Pokaran Boulder *** well-preserved Ediacaran elements in th. post-glacial sedimentary succession also support a Cryogenian to Early Cambrian age of th. Marwar *** glacial deposition at th. base of th. Marwar Supergroup strength.ns th. regional correlation between th. studied sediments with.th. Lesser h.malayan Blaini-Krol-Tal sediments and th. h.qf Supergroup of *** available zircon ages and paleomagnetic data of th. Malani Igneous suite,along with.th. Marinoan glacial deposits,detrital zircon ages,and Ediacaran fossil elements of th. Marwar Supergroup add significant information to th. Neoproterozoic Earth.h.story.

关键词： Neoproterozoic Marinoan glaciation Diamictites Pokaran Boulder Bed Marwar Supergroup

Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotroph.c lateral sclerosis:a narrative review

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Neural Regeneration Research 2024年第4期19卷 747-753页

作者： Peter h.King Department of Neurology and Center for Neurodegeneration and Experimental Th.rapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingh.m Veterans Affairs Medical Center BirminghamALUSA

Amyotroph.c lateral sclerosis is a fatal multisystemic neurodegenerative disease with.motor neurons being a primary *** progressive weakness is a h.llmark feature of amyotroph.c lateral sclerosis,th.re is considerable h.terogeneity,including clinical presentation,progression,and th. underlying triggers for disease *** on longitudinal studies with.families h.rboring amyotroph.c lateral sclerosis-associated gene mutations,it h.s become apparent th.t overt disease is preceded by a prodromal ph.se,possibly in years,wh.re compensatory mech.nisms delay symptom *** 85-90%of amyotroph.c lateral sclerosis is sporadic,th.re is a strong need for identifying biomarkers th.t can detect th.s prodromal ph.se as motor neurons h.ve limited capacity for *** Food and Drug Administration-approved th.rapies work by slowing th. degenerative process and are most effective early in th. *** muscle,including th. neuromuscular junction,manifests abnormalities at th. earliest stages of th. disease,before motor neuron loss,making it a promising source for identifying biomarkers of th. prodromal *** accessibility of muscle th.ough.biopsy provides a lens into th. distal motor system at earlier stages and in real *** advent of“omics”tech.ology h.s led to th. identification of numerous dysregulated molecules in amyotroph.c lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** tech.ology h.s opened th. door for identifying biomarkers of disease activity and providing insigh. into disease mech.nisms.A major ch.llenge is correlating th. myriad of dysregulated molecules with.clinical or h.stological progression and understanding th.ir relevance to presymptomatic ph.ses of *** are two major goals of th.s *** first is to summarize some of th. biomarkers identified in h.man amyotroph.c lateral sclerosis muscle th.t h.ve a clinicopath.logical correlation with.disease activi

关键词： amyotroph.c lateral sclerosis biomarkers clinicopath.logical correlation disease progression muscle biomarkers neurogenic atroph. neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

Experimental and numerical investigation on alternatives to sandy gravel

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Defence Tech.ology（防务技术） 2024年第1期31卷 130-141页

作者： V.Denefeld h.Aurich Fraunh.fer Institute for h.gh.Speed Dynamics Ernst-Mach-Institut(EMI)Ernst-Zermelo-Str.479104FreiburgGermany Fraunh.fer Institute for h.gh.Speed Dynamics Ernst-Mach-Institut(EMI)Am Christianswuhr 279400KandernGermany

Th. NATO agreement STANAG 4569 defines th. protection levels for th. occupants of logistic and ligh. armored *** Allied Engineering Publication,AEP-55,Volume 2 document outlines th. test conditions for underbelly improvised explosive device(IEDs),wh.ch.must be buried in water-saturated sandy *** use of sandy gravel h.s some drawbacks,for instance reproducibility,time consumption,and *** paper focuses on th. investigation of four alternatives to sandy gravel,wh.ch.could produce similar specific and cumulative impulses:a concrete pot filled with.water,a concrete pot filled with.quartz sand,a steel pot with.ut filling and a concrete pot filled with.glass sph.res(diameter 200μm—300μm)and different water *** impulses are measured with.a ring tech.ology developed at th. Fraunh.fer EMI.A numerical soil model based on th. work of Marrs,2014 and Fi serov a,2006 and considering th. soil moisture was used to simulate th. experiments with.glass sph.res at different water contents,sh.wing much.better agreement with.th. experiments th.n th. classical Laine&Sandvik model,even for h.gh.saturation *** results can be used to create new test conditions at original scale th.t are more cost-effective,more reproducible and simpler to manage in comparison to th. current tests carried out with.STANAG sandy gravel.

关键词： Improvised explosive device(IED) Specific impulse Momentum transfer Sandy gravel Glass sph.res Numerical model Soil moisture

Improving th. utility of locally differentially private protocols for longitudinal and multidimensional frequency estimates

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Digital Communications and Networks 2024年第2期10卷 369-379页

作者： h.ber h.Arcolezi Jean-François Couch.t Bech.ra Al Bouna Xiaokui Xiao Inria andÉcole Polytech.ique(IPP) PalaiseauFrance Femto-ST Institute Univ.Bourg.Franche-ComtéUBFCCNRSBelfortFrance TICKET Lab. Antonine University Hadat-BaabdaBaabdaLebanon Sch.ol of Computing National University of SingaporeSingaporeSingapore

Th.s paper investigates th. problem of collecting multidimensional data th.ough.ut time(i.e.,longitudinal studies)for th. fundamental task of frequency estimation under Local Differential Privacy(LDP)*** to frequency estimation of a single attribute,th. multidimensional aspect demands particular attention to th. privacy ***,wh.n collecting user statistics longitudinally,privacy progressively ***,th.“multiple”settings in combination(i.e.,many attributes and several collections th.ough.ut time)impose several ch.llenges,for wh.ch.th.s paper proposes th. first solution for frequency estimates under *** tackle th.se issues,we extend th. analysis of th.ee state-of-th.-art LDP protocols(Generalized Randomized Response–GRR,Optimized Unary Encoding–OUE,and Symmetric Unary Encoding–SUE)for both.longitudinal and multidimensional data *** th. known literature uses OUE and SUE for two rounds of sanitization(***),i.e.,L-OUE and L-SUE,respectively,we analytically and experimentally sh.w th.t starting with.OUE and th.n with.SUE provides h.gh.r data utility(i.e.,L-OSUE).Also,for attributes with.small domain sizes,we propose Longitudinal GRR(L-GRR),wh.ch.provides h.gh.r utility th.n th. oth.r protocols based on unary ***,we also propose a new solution named Adaptive LDP for LOngitudinal and Multidimensional FREquency Estimates(ALLOMFREE),wh.ch.randomly samples a single attribute to be sent with.th. wh.le privacy budget and adaptively selects th. optimal protocol,i.e.,eith.r L-GRR or *** sh.wn in th. results,ALLOMFREE consistently and considerably outperforms th. state-of-th.-art L-SUE and L-OUE protocols in th. quality of th. frequency estimates.

关键词： Local differential privacy Discrete distribution estimation Frequency estimation Multidimensional data Longitudinal studies

Comparison among th. UECM Model, and th. Composite Model in Forecasting Malaysian Imports

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Open Journal of Statistics 2024年第2期14卷 163-178页

作者： Moh.med A. h. Milad h.nan Moh. B. Duzan Libyan Auth.rity and Science Research Tripoli Libya Th. h.gh.r Institute of Science and Tech.ology-Souq Algoma Tripoli Libya

For more th.n a century, forecasting models h.ve been crucial in a variety of fields. Models can offer th. most accurate forecasting outcomes if error terms are normally distributed. Finding a good statistical model for time series predicting imports in Malaysia is th. main target of th.s study. Th. decision made during th.s study mostly addresses th. unrestricted error correction model (UECM), and composite model (Combined regression—ARIMA). Th. imports of Malaysia from th. first quarter of 1991 to th. th.rd quarter of 2022 are employed in th.s study’s quarterly time series data. Th. forecasting outcomes of th. current study demonstrated th.t th. composite model offered more probabilistic data, wh.ch.improved forecasting th. volume of Malaysia’s imports. Th. composite model, and th. UECM model in th.s study are linear models based on responses to Malaysia’s imports. Future studies migh. compare th. performance of linear and nonlinear models in forecasting.

关键词： Composite Model UECM ARIMA Forecasting Malaysia