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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： n.IQBAL J.CHOI S.F.SHAH C.LEE S.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline ni-rich LinixMnyCo_(z)O_(2)(x≥0.8)(nMC)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary nMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of nMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation ni-rich LinixMnyCo_(z)O_(2)(x>0.8)(nMC)

The interaction of the structure-directing agent with the zeolite framework determines germanium distribution in SCM-15 germanosilicate

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 105-114页

作者： Stoyan P.Gramatikov Petko St.Petkov Zhendong Wang Weimin Yang Georgi n.Vayssilov Faculty of Chemistry and Pharmacy University of Sofia1126 SofiaBulgaria State Key Laboratory of Green Chemical Engineering and Industrial Catalysis Sinopec Shanghai Research Institute of Petrochemical Technology Co.Ltd.Shanghai 201208China

We report results from computational modeling of the relative stability of germanosilicate SCM-15 structure due to different distribution of germanium heteroatoms in the double four-member rings(D4Rs)of the framework and the orientation of the structure directing agent(SDA)molecules in the as-synthesized *** calculated relative energies of the bare zeolite framework suggest that structures with germanium ions clustered in the same D4Rs,e.g.,with large number of Ge–O-Ge contacts,are the most *** simulations of various orientations of the SDA in the pores of the germanosilicate zeolite show different stability order-the most stable models are the structures with germanium spread among all ***,for SCM-15 the stabilization due to the presence of the SDA and their orientation,is thermodynamic factor directing both the formation of specific framework type and Ge distribution in the framework during the *** relative stability of bare structures with different germanium distribution is of minor *** differs from SCM-14 germanosilicate,reported earlier,for which the stability order is preserved in presence of ***,even for zeolites with the same chemical composition and SDA,the characteristics of their framework lead to different energetic preference for germanium distribution.

关键词： zeolite density functional theory structure-directing agent SCM-15

Output feedback adaptive super twisting sliding mode control for quadrotor UAVs

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Control Theory and Technology 2024年第1期22卷 92-105页

作者： Oscar Salas-Peña Jesus DeLeón-Morales Susana V.Gutiérrez-Martínez École Centrale de nantes-LS2n UMR 6004 CNRS44300NantesFrance Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo León66451San Nicolás de Los GarzaMexico

In this paper, a sliding mode control with adaptive gain combined with a high-order sliding mode observer to solve the tracking problem for a quadrotor UAV is addressed, in presence of bounded external disturbances and parametric uncertainties. The high order sliding mode observer is designed for estimating the linear and angular speed in order to implement the proposed scheme. Furthermore, a Lyapunov function is introduced to design the controller with the adaptation law, whereas an.analysis of finite time convergence towards to zero is provided, where sufficient conditions are obtained. Regarding previous works from literature, one important advan.age of proposed strategy is that the gains of control are parameterized in terms of only one adaptive parameter, which reduces the control effort by avoiding gain overestimation. numerical simulations for tracking control of the quadrotor are given to show the performance of proposed adaptive control–observer scheme.

关键词： Adaptive super twisting controller High-order sliding modes observer UAV

Current considerations for the surgical management of gallbladder adenomas

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1507-1512页

作者： Efstathios T Pavlidis Ioannis n Galanis Theodoros E Pavlidis The Second Department of Propaedeutic Surgery Hippokration General HospitalSchool of MedicineAristotle University of ThessalonikiThessaloniki 54642Greece

Gallbladder adenomas are rare lesions(0.5%)associated with potential malignant transformation,particularly with gallbladder adenomas that are≥1 cm in *** detection and management are crucial for preventing lethal carcinoma *** polyps can often be distinguished from the more often nonneo-plastic cholesterol pseudopolyps(5%-10%),which are *** is the first-line tool for initial diagnosis and follow-up when *** question is whether cholecystectomy is always necessary for all *** manage-ment of gallbladder adenomas is determined according to the size of the tumor,the growth rate of the tumor,the patient’s symptoms and whether risk factors for malignancy are ***≥1 cm in size,an.age>50 years and a familial history of gallbladder carcinoma are indications for immediate laparoscopic ***,ultrasound follow-up is *** adenomas 6-9 mm in size,the absence of≥2 mm growth at 6 months,one year,and two years,as well as an.adenoma sizedng risk factors indicates that no further surveillance is ***,it would be preferable to individualize the management in doubtful *** interventional modalities for preserving the gallbladder need further evaluation,especially to determine the long-term outcomes.

关键词： Biliary diseases True neoplastic polyps Gallbladder adenomas Benign bi-liary tumors Gallbladder polyps Extrahepatic biliary neoplasms

An Involution over Dyck Paths Related with Stirling Statistics

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Journal of Mathematical Research with Applications 2024年第4期44卷 437-443页

作者： Peng CAO Joan.a n.CHEn College of Science Tianjin University of Technology

We construct an involution over Dyck paths, which implies the distribution of statistics “the number of peak”, “the number of returns” and “the height of the last peak”. As an.application, equidistributions of s...

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Fungal infections in immunocompromised critically ill patients

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Journal of Intensive Medicine 2024年第3期4卷 299-306页

作者： JoséGarnacho-Montero Irene Barrero-García Cristina León-Moya Unidad Clínica de Cuidados Intensivos Hospital Universitario Virgen MacarenaSevillaSpain

Diverse pathogenic fungi can produce severe infections in immunocompromised patients, thereby justifying intensive care unit (ICU) admissions. In some cases, the infections can develop in immunocompromised patients who were previously admitted to the ICU. Aspergillus spp., Pneumocystis jirovecii, Candida spp., and Mucorales are the fungi that are most frequently involved in these infections. Diagnosis continues to be challenging because symptoms and signs are unspecific. Herein, we provide an in-depth review about the diagnosis, with emphasis on recent advances, and treatment of these invasive fungal infections in the ICU setting.

关键词： Invasive aspergillosis Immunocompromised patient Critically ill patient Antifungal Invasive candidiasis Pneumocystis jirovecii

Optimum Profiles of Endwall Contouring for Enhanced net Heat Flux Reduction and Aerodynamic Performance

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Journal of Harbin Institute of Technology(new Series) 2024年第2期31卷 80-92页

作者： Arjun K S Tide P S Biju n Division of Mechanical Engineering School of EngineeringCochin University of Science&TechnologyKalamassery 682022India

Successfully utilized non-axisymmetric endwalls to enhance turbine efficiencies(aerodynamic and turbine inlet temperatures)by controlling the characteristics of the secondary flow in a blade *** is accomplished by steady-state numerical hydrodynamics and deep knowledge of the field of *** of the interaction between mainstream and purge flow contributing supplementary losses in the stage,non-axisymmetric endwalls are highly susceptible to the inception of purge flow exit compared to the flat and any advan.age rapidly *** conclusions reveal that the supreme endwall pattern could yield a lowering of the gross pressure loss at the design stage and is related to the size of the top-loss location being productively *** has led to diminished global thermal exchange lowered in the passage of the vane *** reverse flow adjacent to the suction side corner of the endwall is migrated farther from the vane surface,as the deviated pressure spread on the endwall accelerates the flow and progresses the reverse flow core still *** depleted association between the tornado-like vortex and the corner vortex adjacent to the suction side corner of the endwall is the dominant mechanism of control in the contoured end *** this publication,we show that the non-axisymmetric endwall contouring by selective numerical shape change method at most prominent locations is advan.ageous in lowering the thermal load in turbines to augment the net heat flux reduction as well as the aerodynamic performance using multi-objective optimization.

关键词： endwall contouring turbine vane heat transfer phantom cooling coolant injection net heat flux reduction aerodynamic performance

Deep optics preconditioner for modulation-free pyramid wavefront sensing

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Photonics Research 2024年第2期12卷 301-312页

作者： FELIPE GUZMÁn JORGE TAPIA CAMILO WEInBERGER nICOLÁS HERnÁnDEZ JORGE BACCA BEnOIT nEICHEL ESTEBAn VERA School of Electrical Engineering Pontificia Universidad Católica de Valparaı´soValparaı´soChile Department of Systems Engineering Universidad Industrial de SantanderBucaramangaColombia Laboratoire d’Astrophysique de Marseille MarseilleFrance

The pyramid wavefront sensor(PWFS)can provide the sensitivity needed for demanding adaptive optics applications,such as imaging exoplanets using the future extremely large telescopes of over 30 m of diameter(D).However,its exquisite sensitivity has a limited linear range of operation,or dynamic range,although it can be extended through the use of beam modulation—despite sacrificing sensitivity and requiring additional optical *** by artificial intelligence techniques,this work proposes to train an optical layer—comprising a passive diffractive element placed at a conjugated Fourier plane of the pyramid prism—to boost the linear response of the pyramid sensor without the need for cumbersome *** develop an end-2-end simulation to train the diffractive element,which acts as an optical preconditioner to the traditional least-square modal phase estimation *** results with a large range of turbulence conditions show a noticeable improvement in the aberration estimation performance equivalent to over 3λ∕D of modulation when using the optically preconditioned deep PWFS(DPWFS).Experimental results validate the advan.ages of using the designed optical layer,where the DPWFS can pair the performance of a traditional PWFS with 2λ∕D of *** and adding an optical preconditioner to the PWFS is just the tip of the iceberg,since the proposed deep optics methodology can be used for the design of a completely new generation of wavefront sensors that can better fit the demands of sophisticated adaptive optics applications such as ground-to-space and underwater optical communications and imaging through scattering media.

关键词： process optics pyramid

Turbine Passage Secondary Flow Dynamics and Endwall Heat Transfer Under Different Inflow Turbulence

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Journal of Harbin Institute of Technology(new Series) 2024年第3期31卷 51-62页

作者： Arjun K S Tide P S Biju n Division of Mechanical Engineering School of EngineeringCochin University of Science&TechnologyKalamassery 682022India

This study presents endwall hydrodynamics and heat transfer in a linear turbine cascade at Re 5×105 at low and high intensities of *** are numerically predicted using the stan.ard SST model and Reθ-γtransition model as well as using the high-resolution LES *** major secondary flow components,comprising the horseshoe,corner,and passage vortices are recognized and the impact on heat or mass transfer is *** complicated behavior of turbine passage secondary flow generation and establishment are impacted by the perspective of boundary layer attributes and inflow *** passage vortex concerning the latest big leading-edge vane is generated by the enlargement of the circulation developed at the first instance adjacent to the pressure side becomes powerful and mixes with other vortex systems during its migration towards the suction *** study conclusions reveal that substantial enhancements are attained on the endwall surface,for the entire spanwise blade extension on the pressure surface,and in the highly 3-D region close to the endwall on the suction *** forecasted suction surface thermal exchange depicts great conformity with the measurement values and precisely reproduces the enhanced thermal exchange owing to the development and lateral distribution of the secondary flows along the midspan of the blade passage *** impacts of the different secondary flow structures on the endwall thermal exchange are described in depth.

关键词： turbine vane heat transfer endwall turbulence secondary flow

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.Bilen B.Birol M.n.Saridede S.S.Kaplan M.S.Sonmez Department of Metallurgical and Materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and Materials Science Stevens Institute of TechnologyNew JereyUSA Department of Metallurgical and Materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s *** can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth *** the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent *** the yields were *** the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HnO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were *** highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 *** energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction ***,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed ***,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method