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Journal of Materials Science & Technology 2024年第6期173卷 218-224页

作者： l.Y.Hao E.g.Fu State Key laboratory of Nuclear Physics and Technology Department of Technical PhysicsSchool of PhysicsPeking UniversityBeijing 100871China

Superconducting materials with high critical temperature have the potential to revolutionize many fields,including military,electronic communications,and power ***,scientists around the world have been tirelessly working with the ultimate goal of achieving high-temperature *** 2023,a preprint by lee et *** South Korea claimed the discovery of ultra-high-temperature superconductivity with a critical temperature of up to 423 K in Cu-doped lead-apatite(lK-99)(arXiv:2307.12008,arXiv:2307.12037),which caused a worldwide sensation and ***,the electronic structures,phonon dynamics,and electrical conductivities of lK-99 and its parent compound lead-apatite have been calculated using first-principles *** results show that the lead-apatite compound and the lK-99 compound are insulator and half-metal *** flat band characteristic is consistent with previous *** electrical conductivity of the lK-99 compound shows two extreme points,and the electrical conductivity along the C-axis increases significantly after 400 *** phonon dispersion spectra of the compounds were investigated,demonstrating their dynamic instability.

关键词： Superconductivity lK-99 lead-apatite First-principles calculation

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite Buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： l.Iniya B.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a Bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process

Combustion characteristics of low-quality lignite for different bed material sphericities in a circulating fluidized bed boiler:A numerical study

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Particuology 2024年第7期90卷 364-382页

作者： Barış gürel gülşah Karaca Dolgun Osman İpek Ali Keçebaş Department of Mechanical Engineering Engineering FacultySüleyman Demirel UniversityÇünürIspartaTurkey Department of Energy Systems Engineering Technology FacultyMuğla SıtkıKoçman UniversityKötekliMenteşeMuğlaTurkey

This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key ***,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of glI-Tunçbilek *** levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure *** combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole *** NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing.l.w.NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and ***,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.

关键词： Circulating fluidized bed boiler Computational particle fluid dynamics method Particle sphericity ratios NO_(x)and SO_(2)emissions Energy production efficiency

Origins of perturbations in dayside equatorial ground magnetograms

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Earth and Planetary Physics 2024年第1期8卷 215-221页

作者： Syau-Yun w.Hsieh David g.Sibeck The Johns Hopkins University Applied Physics laboratory LaurelMarylandUSA NASA goddard Space Flight Center GreenbeltMarylandUSA

To determine the cause(s)of perturbations seen in dayside equatorial ground magnetograms,we conducted a systematic survey of simultaneous ground-based and geosynchronous satellite-based observations during the 90-day period from December 1,2020 to February 28,*** examined Huancayo ground magnetometer observations from 14:00:00 to 20:00:00 UT each day,during which Huancayo passed through local *** those data we chose perturbation events selected on the basis of large(>20 nT)event amplitude and classified the selected events as responding primarily to solar wind pressure,or to variations in the north/south component of the interplanetary magnetic field(IMF Bz),or perhaps in part to *** results show that an equivalent number of events were identified for each model during this 90-day *** in the lagged solar wind dynamic pressure routinely correspond to nearly simultaneous sudden impulses recorded at both geosynchronous orbit and on the *** in IMF Bz produce erosion signatures at geosynchronous orbit and can correspond to ground events if lag times for reconnection to enhance convection in the magnetosphere are taken into account.

关键词： dayside magnetosphere dayside equatorial ionosphere geosynchronous magnetic field

Creep-induced redistribution of alloying elements in CZ1 zirconium alloys

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Journal of Materials Science & Technology 2024年第6期173卷 31-44页

作者： w.T.lin Q.Y.lv D.Jiao l.B.Zhang J.Tan g.Sha J.Hu China Nuclear Power Technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission electron microscopy(TEM)and atom probe tomography(APT)investigations to address creep-induced redistribution of alloying elements in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at dislocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： Zirconium alloy Thermal creep grain boundary segregation Dislocation segregation Cu-rich nanoclusters

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： C.g.PAVITHRA B.J.gIREESHA M.l.KEERTHI Department of Pg Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field

Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment

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Journal of Renewable Materials 2024年第10期12卷 1791-1810页

作者： Martha l.Sánchez g.Capote Universidad Militar Nueva granada Programa de Ingeniería CivilBogotá110111Colombia Facultad de Ciencias Departamento de FísicaUniversidad Nacional de ColombiaBogotá111321Colombia

The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional *** production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable *** this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction *** the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were *** fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and Salix viminalis *** improve their compatibility with the castor oil resin,a cold argon plasma treatment was *** effect of the treatment on the properties of the fibers and the panels was *** density,water absorption capacity,and swelling percentage were ***,compression,static bending,and linear buckling tests were carried *** study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage *** made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness *** models were constructed using commercial finite element *** comparing the numerical results with the experimental ones,differences of less than 15%were seen,demonstrating that the models allow adequately predicting the analyzed *** comparing the values obtained with the characteristic values of oriented strand board,the results suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particles and other composite materials in several applications in th

关键词： Unconventional materials nonstructural panels plantﬁbers surface treatment physical properties mechanical properties

Efficient fidelity estimation:alternative derivation and related applications

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Communications in Theoretical Physics 2024年第9期76卷 16-20页

作者： Diego S Starke Marcos l w Basso Jonas Maziero Physics Department Center for Natural and Exact SciencesFederal University of Santa MariaRoraima Avenue 1000Santa MariaRS97105-900Brazil Center for Natural and Human Sciences Federal University of ABCAvenue of the StatesSanto AndréSão Paulo09210-580Brazil

In[***.A 107012427(2023)],Baldwin and Jones prove that Uhlmann–Jozsa’s fidelity between two quantum statesρandσ,i.e.,F(ρ,σ)=(Tr√√ρσ√ρ)^(2),can be written in a simplified form as F(ρ,σ)=(Tr√ρσ)^(2).In this article,we give an alternative proof of this result,using a function power series expansion and the properties of the trace *** approach not only reinforces the validity of the simplified expression but also facilitates the exploration of novel dissimilarity functions for quantum states and more complex trace functions of density operators.

关键词： Ulhmann–Jozsa fidelity Rényi entropy efficient fidelity estimation Chebyshev polynomials

Tumor necrosis factor-alpha, transforming growth factor-beta, degree of lower urinary tract symptoms as predictors of erectile dysfunction in benign prostatic hyperplasia patients

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Asian Journal of Urology 2024年第2期11卷 280-285页

作者： gede w.K.Duarsa Yeremia g.Kusumah Ronald Sugianto Pande M.w.Tirtayasa Tjokorda g.B.Mahadewa Department of Urology Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia Department of general Surgery Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia Medical Doctor Study Program Faculty of MedicineUniversitas UdayanaBaliIndonesia Department of Urology Faculty of MedicineUniversitas UdayanaUniversitas Udayana Teaching HospitalBaliIndonesia Department of Neurosurgery Faculty of MedicineUniversitas UdayanaProf.Dr.I.G.N.G Ngoerah General HospitalBaliIndonesia

Objective: Erectile dysfunction (ED) is a condition of insufficient penile erection, consistently or recurrently, for sexual activity. Tumor necrosis factor-alpha (TNF-α) induces transforming growth factor-beta (TgF-β), which causes the transition of epithelial cells into mesenchymal cells that affect ED. This study aimed to evaluate the roles of TNF-α, TgF-β, degree of lower urinary tract symptoms, and prostatic volume for the presence of ED in benign prostatic hyperplasia (BPH) ***: Our study performed an analytic observational retrospective cohort study using secondary data from four hospitals in Bali, Indonesia, including medical records and other administrative data. The sample was BPH patients with several history ***: Our sample was 83 respondents, ranging from 50 years to 80 years, 61 respondents with ED and 22 with non-ED. The International Prostate Symptom Score showed a significant result, which indicates that ED is more common in patients with higher International Prostate Symptom Score (p=0.002). Moreover, the TNF-α of ≥43.9 pg/mg and TgF-β of ≥175.8 pg/ml were significantly associated with the presence of ED in BPH patients (plts, prostate volume is not significant with ED (p=0.947).Conclusion: TNF-α, TgF-β, and lower urinary tract symptoms severity can predict the occurrence of ED in BPH, while prostatic volume was not significant.

关键词： Prostate enlargement Biomarker Erectiledysfunction Riskfactor

A multi-sensor appiproach to calving detection

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Information Processing in Agriculture 2024年第1期11卷 45-64页

作者： Anita Z.Chang David l.Swain Mark g.Trotter Institute for Future Farming Systems School of HealthMedicaland Applied SciencesCentral Queensland UniversityRockhamptonQueensland 4700Australia

The advent of remote livestock monitoring systems provides numerous possibilities for improving on-farm productivity,efficiency,and *** potential application for these systems is for the detection of calving *** study describes the integration of data from multiple sensor sources,including accelerometers,global navigation satellite systems(gNsS),an accelerometer-derived rumination algorithm,a walk-over-weigh unit,and a weather station for parturition detection using a support vector machine *** best performing model utilised data from gNsS,the ruminating algorithm,and weather stations to achieve 98.6%accuracy,with 88.5%sensitivity and 100%*** topranking features of this model were primarily gNSS *** study provides an overview as to how various sensor systems could be integrated on-farm to maximise calving detection for improved production and welfare outcomes.

关键词： Accelerometer gNSS gPS Rumination Sensor wOw