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Comparative utility of vestibular function tests in patients with peripheral and central vestibular dysfunction

journal of Otology 2024年第1期19卷 5-9页

作者： Cameron B.fattahi Christopher Zaro janice j.Chung Richard f.Lewis Divya A.Chari Department of Otolaryngology-Head and Neck Surgery UMASS Memorial Medical CenterUniversity of Massachusetts Chan Medical SchoolWorcesterMAUSA jenks Vestibular Physiology Laboratory Massachusetts Eye and EarBostonMAUSA Department of Otolaryngology-Head and Neck Surgery Massachusetts Eye and EarHarvard Medical SchoolBostonMAUSA Department of Neurology Harvard Medical SchoolBostonMAUSA

Background: Bithermal caloric irrigation, video head impulse test(vHIT), and rotational testing are commonly used to assess peripheral vestibular function, but the relative clinical utility of each test in differentiating patients with peripheral vestibulopathy is debated.Objectives: To determine whether(1) the combination of two or more vestibular tests enhances diagnostic utility over a single test;(2) abnormal test results on vestibular tests correlate with one another.Methods: Retrospective analysis of data collected from multidisciplinary vestibular clinics at two academic medical centers from 2016 to 2022.Results: 150 patients(54.10 ± 15.09 years, 88 females) were included. No individual test was significantly better at predicting the presence of peripheral vestibular damage(p > 0.05). vHIT test results improved significantly when combined with either the caloric test(p = 0.007) or rotary chair test(p = 0.039). Caloric and rotational testing had high sensitivity(74.65% and 76.06%, respectively) and specificity(83.54% and 78.48%, respectively). vHIT demonstrated excellent specificity(89.87%) but poor sensitivity(47.89%). Caloric, vHIT, and rotary chair tests results did not correlate with one another(p > 0.05).Conclusions: Vestibular function tests have comparable diagnostic utility, yet each offers unique advantages. Caloric and rotational testing may be best suited for screening peripheral damage and vHIT may function ideally as a confirmatory test.

关键词： vestibular patients specificity

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White light emission in 0D halide perovskite[(CH_(3))_(3)S]_(2)SnCl_(6)·H_(2)O crystals through variation of doping ns^(2) ions

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frontiers of Optoelectronics 2024年第1期17卷 57-66页

作者： Yitong Lin Yu Zhong Yangpeng Lin jiawei Lin Lei Pang Zhilong Zhang Yi zhao Xiao‑Ying Huang Ke‑zhao Du fujian Provincial Key Laboratory of Advanced Materials Oriented Chemical Engineering Collage of Chemistry and Material ScienceFujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Qinghai Environmental Monitoring Center Xining 810000China Strait Institute of flexible Electronics(SIfE Future Technologies)Fujian Normal University and Strait Laboratory of Flexible Electronics(SLoFE)Fuzhou 350007China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

With the rapid development of white LEDs,the research of new and efficient white light emitting materials has attracted increasing attention.Zero dimensional(0D)organic–inorganic hybrid metal halide perovskites with superior luminescent property are promising candidates for LED application,due to their abundant and tailorable structure.Herein,[(CH_(3))_(3)S]_(2)SnCl_(6)・H_(2)O is synthesized as a host for dopant ions Bi^(3+)and Sb^(3+).The Sb^(3+)doped,or Bi^(3+)/Sb^(3+)co-doped,[(CH_(3))3S]_(2)SnCl_(6)・H_(2)O has a tunable optical emission spectrum by means of varying dopant ratio and excitation wavelength.As a result,we can achieve single-phase materials suitable for emission ranging from cold white light to warm white light.The intrinsic mechanism is examined in this work,to clarify the dopant effect on the optical properties.The high stability of title crystalline material,against water,oxygen and heat,makes it promising for further application.

关键词： 0D Metal halide White light Perovskite Ions doping Excitation dependent

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Stochastic seismic inversion and Bayesian facies classification applied to porosity modeling and igneous rock identification

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Petroleum Science 2024年第2期21卷 918-935页

作者： fábio júnior Damasceno fernandes Leonardo Teixeira Antonio fernando Menezes freire Wagner Moreira Lupinacci Exploratory Interpretation and Reservoir Characterization Group(GIECAR) Department of Geology and GeophysicsFederal Fluminense UniversityNiter oiRJ24210-346Brazil Petrobras Rio de JaneiroRJ20231-030Brazil National Institute of Science and Technology of Petroleum Geophysics(INCT-GP/CNPQ) Niter oiRJ24210-346Brazil

We apply stochastic seismic inversion and Bayesian facies classification for porosity modeling and igneous rock identification in the presalt interval of the Santos Basin. This integration of seismic and well-derived information enhances reservoir characterization. Stochastic inversion and Bayesian classification are powerful tools because they permit addressing the uncertainties in the model. We used the ES-MDA algorithm to achieve the realizations equivalent to the percentiles P10, P50, and P90 of acoustic impedance, a novel method for acoustic inversion in presalt. The facies were divided into five: reservoir 1,reservoir 2, tight carbonates, clayey rocks, and igneous rocks. To deal with the overlaps in acoustic impedance values of facies, we included geological information using a priori probability, indicating that structural highs are reservoir-dominated. To illustrate our approach, we conducted porosity modeling using facies-related rock-physics models for rock-physics inversion in an area with a well drilled in a coquina bank and evaluated the thickness and extension of an igneous intrusion near the carbonate-salt interface. The modeled porosity and the classified seismic facies are in good agreement with the ones observed in the wells. Notably, the coquinas bank presents an improvement in the porosity towards the top. The a priori probability model was crucial for limiting the clayey rocks to the structural lows. In Well B, the hit rate of the igneous rock in the three scenarios is higher than 60%, showing an excellent thickness-prediction capability.

关键词： Stochastic inversion Bayesian classification Porosity modeling Carbonate reservoirs Igneous rocks

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Modelling dynamic pantograph loads with combined numerical analysis

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Railway Engineering Science 2024年第1期32卷 81-94页

作者： f.f.jackson R.Mishra j.M.Rebelo j.Santos P.Antunes j.Pombo H.Magalhaes L.Wills M.Askill School of Computing and Engineering University of HuddersfieldHuddersfieldUK School of Computing and Engineering Institute of Railway ResearchUniversity of HuddersfieldHuddersfieldUK IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal ISEL Instituto Politecnico de LisboaLisbonPortugal Hitachi Rail Newton AycliffeUK Wabtec/Brecknell Willis ChardUK

Appropriate interaction between pantograph and catenary is imperative for smooth operation of electric trains.Changing heights of overhead lines to accommodate level crossings,overbridges,and tunnels pose significant challenges in maintaining consistent current collection performance as the pantograph aerodynamic profile,and thus aerodynamic load changes significantly with operational height.This research aims to analyse the global flow characteristics and aerodynamic forces acting on individual components of an HSX pantograph operating in different configurations and orientations,such that the results can be combined with multibody simulations to obtain accurate dynamic insight into contact forces.Specifically,computational fluid dynamics simulations are used to investigate the pantograph component loads in a representative setting,such as that of the recessed cavity on a Class 800 train.from an aerodynamic perspective,this study indicates that the total drag force acting on non-fixed components of the pantograph is larger for the knuckle-leading orientation rather than the knuckle-trailing,although the difference between the two is found to reduce with increasing pantograph extension.Combining the aerodynamic loads acting on individual components with multibody tools allows for realistic dynamic insight into the pantograph behaviour.The results obtained show how considering aerodynamic forces enhance the realism of the models,leading to behaviour of the pantograph-catenary contact forces closely matching that seen in experimental tests.

关键词： Pantograph-catenary interaction Pantograph aerodynamics Computational fluid dynamics Pantograph loads Current collection performance

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In-situ construction of epitaxial phase for boosting zinc nucleation on three-dimensional interface

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Progress in Natural Science:Materials International 2024年第3期34卷 578-584页

作者： Xin He Zhe Zhu Xiaoqiao Liao Kai Yang Yixue Duan Linfeng Lv Chuan zhao Wei zhao jibing Chen Peng Tian Xiaoyu Liu Liang He School of Mechanical Engineering State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Sichuan University School of Chemistry Faculty of Science University of New South Wales School of Materials Science and Engineering Sichuan University of Science & Engineering School of Mechanical Engineering Wuhan Polytechnic University Med+X Center for Manufacturing West China Hospital Sichuan University Yibin Industrial Technology Research Institute of Sichuan University Yibin R&D Park of Sichuan University

Interface modification of zinc（Zn） metal anode with conductive three-dimensional（3D） structure is widely utilized in zinc ion batteries. However, the uniformity of zinc nucleation on surface microstructure is rarely investigated which exacerbates the tip effect and raises unstable risk. Herein, a strategy via the initial copper（Cu）alloying and following sulfurization treatment is reported to accomplish boosted uniform nucleation of zinc on the modified layer with dense microstructures. This epitaxial sulfide phase not only improves the wetting area to revitalize the microstructural surface, but also forms a bifunctional zincophilic Cu2S/CuZn alloy interface layer,which combines the merits of guided local ions diffusion and improved zinc nucleation environment. As a result, a homogeneous growth of zinc on the 3D structural substrate can be realized, and cycling stability of the achieved Cu2S/CuZn electrode with a practical capacity of 1 mAh cm-2under 1 mA cm-2or amplified current density of 10 mA cm-2is significantly enhanced. This work provides an epitaxial strategy in constructing a bifunctional zincophilic interface layer for boosting zinc nucleation, and offers a new perspective on the modification of 3D surface structure for stabilization of zinc anode.

关键词： CuZn alloy Hydrophilicity Sulfide Zn anode Zn metal battery

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Superhydrophilic nickel hydroxide ultrathin nanosheets enable high-performance asymmetric supercapacitors

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Rare Metals 2024年第1期43卷 138-147页

作者： Yi-Ran Wang fei Zhang jian-Min Gu Xiao-Yu zhao Ran zhao Xing Wang Tian-Hui Wu jing Wang ji-Dong Wang De-Song Wang State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryYanshan UniversityQinhuangdao 066004China Department of food and Pharmaceutical Engineering Suihua UniversitySuihua 152000China School of Chemical Science and Engineering Tongji UniversityShanghai 200092China School of Sciences Hebei University of Science and TechnologyShijiazhuang 050018China

Superhydrophilic surfaces have been applied for supercapacitor;however,during energy storage reaction,how the wettability affects the process of electrochemical reaction specifically is still unclear.Herein,we demonstrate superhydrophilic surface for promotion of electrochemical reactions by liquid affinity and further explain the mechanism,where the transition of the wettability state caused by the change in surface free energy is the main reason for the obvious increase in specific capacitance.Through citric acid assistance strategy,an intrinsically hydrophobic Ni(OH)_(2)thick nanosheets(HNHTNs,16 nm)can be transitioned into superhydrophilic Ni(OH)_(2)ultrathin nanosheets(SNHUNs,6.8 nm),where the water contact angle was 0°and the surface free energy increased from 8.6to 65.8 mN·m^(-1),implying superhydrophilicity.Compared with HNHTNs,the specific capacitance of SNHUNs is doubled:from 1230 f·g^(-1)(HNHTNs)to 2350 f·g^(-1)(2A·g^(-1))and,even at 20 A·g^(-1),from 833 f·g^(-1)(HNHTNs)to 1670 f·g^(-1).The asymmetric capacitors assembled by SNHUNs and activated carbon show 52.44 Wh·kg^(-1)at 160W·kg^(-1)and excellent stability with~90%retention after5000 cycles(~80%retention after 9500 cycles).The promotion of electrochemical performances is ascribed to the change of surface wettability caused by surface free energy,which greatly increase affinity of electrode to the surrounding liquid environment to reduce the interface resistance and optimize the electron transport path.

关键词： Asymmetric supercapacitor Superhydrophilic interface Transition metal hydroxides Ultrathin nanosheets High specific capacitance

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Revealing Al-O/Al-f reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments:A reactive molecular dynamics study meshing together experimental validation

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Defence Technology（防务技术） 2024年第4期34卷 313-327页

作者： Gang Li Chuande zhao Qian Yu fang Yang jie Chen Institute of Chemical Materials China Academy of Engineering Physics(CAEP)P.O.Box 919-311Mianyang 621900SichuanChina

Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing environments.for instance,Al-O reaction is the most common pathway to release limited energy while Al-f reaction has received much attentions to enhance Al combustion efficiency.However,microscopic understanding of the Al-O/Al-f reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion efficiency.In this work,for the first time,Al-O/Al-f reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion experiments.Three RMD simulation systems of Al core/O_(2)/Hf,n-Al/O_(2)/Hf,and n-Al/O_(2)/Cf4 with oxygen percentage ranging from 0%to 100%have been performed.The n-Al combustion in mixed O_(2)/Cf_4 environments have been conducted by constant volume combustion experiments.RMD results show that Al-O reaction exhibits kinetic benefits while Al-f reaction owns thermodynamic benefits for n-Al combustion.In n-Al/O_(2)/Hf,Al-O reaction gives faster energy release rate than Al-f reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/Hf and n-Al/O_(2)/Cf_4,respectively.In combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion heat.Importantly,Al-O reaction prefers to occur on the surface regions while Al-f reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-f reactions.The synergistic effect of Al-O/Al-f reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.

关键词： Al-O/Al—f reaction Kinetic benefits Thermodynamic benefits Molecular dynamics Combustion

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Effect of phase transition during roasting of Mountain Pass rare earth concentrate on leaching efficiency of rare earths

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journal of Rare Earths 2024年第2期42卷 409-414,I0006页

作者： Yanyan zhao Xu Sun Deliang Meng Xiangsheng Liu Qiang Zhong Zongyu feng National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.Beijing0088China Rare Earth functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiongan071700China General Research Institute for Nonferrous Metals Beijing100088China

To find a greener and more economical approach for treating the Mountain Pass rare earth concentrate(MPREC),a novel "Combination Method",including the processes of oxidizing roasting,HCI leaching and sulfuric acid roasting,is proposed in this research.In this paper,the effect of phase transition behavior in hydrochloric acid leaching during oxidative roasting at 450-600℃ was studied.During roasting,the bastnasite in MPREC is decomposed into CeLa_(2)O_(3)f_(3) and(Ce_(0.33),La_(0.33),Ca_(0.33))O_(1.5).As the CeLa_(2)O_(3)f_(3) phase has the fluorine-fixation effect,the generated CeLa_(2)O_(3)f_(3) phase can not be dissolved by HCI after roasting at 500 and 550℃,but it can be decomposed by HCI after roasting at over 600℃,resulting in the improvement of the leaching rate of total f element.The maximum leaching efficiency of rare earth elements(REEs) can reach 70.32 wt% at the roasting temperature of 550℃.After roasting at over 600℃,some f^-ions in the solution combined with RE^(3+) to form REf_(3) precipitate and enter the leaching residue,and the others are in the form of [Cef_(3)]^+ in the leaching solution during leaching,therefore,the leaching efficiency of non-ce rium REEs decreases while that of cerium element increases.This work provides basic research for optimizing the actual production process of MPREC.

关键词： Mountain pass rare earth mine Roasting Phase change Rare earths

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Nano-effect enhanced cooperative luminescence of Yb^(3+) clusters in bulk materials

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journal of Rare Earths 2024年第3期42卷 473-478,I0002页

作者： Daguang Li jiahao Cui Yanhui Dong Hao Cui Dan zhao Weiping Qin State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun130012China

In order to improve the multi-ion cooperative transition, we proposed and exploited a novel nanoscale effect, namely the nanoshell effect in bulk materials. Based on the effect, an optimal material structure was designed by coating the surfaces of Ca f_(2):Yb^(3+)micron size particles with ZrO_(2). An about 2 times higher intensity of cooperative luminescence is observed upon laser excitation at 980 nm. Dynamical analysis exhibits that the novel effect plays a key role in improving the performance of cooperative transitions. Our results also suggest that the nanoshell effect in bulk materials is likely to be significant in some special cases, which have not been reported yet in the literature.

关键词： Yb^(3+)cluster ZrO_(2) Nanoshell Enhancement Cooperative luminescence Rare earths

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Recent research progress in the mechanism and suppression of fusion welding-induced liquation cracking of nickel based superalloys

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International journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1072-1088页

作者： Zongli Yi jiguo Shan Yue zhao Zhenlin Zhang Aiping Wu Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China College of Engineering China Agricultural UniversityBeijing 100091China State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China School of Material Science and Engineering Southwest Jiaotong UniversityChengdu 610031China

Nickel-based superalloys are extensively used in the crucial hot-section components of industrial gas turbines,aeronautics,and astronautics because of their excellent mechanical properties and corrosion resistance at high temperatures.fusion welding serves as an effective means for joining and repairing these alloys;however,fusion welding-induced liquation cracking has been a challenging issue.This paper comprehensively reviewed recent liquation cracking,discussing the formation mechanisms,cracking criteria,and remedies.In recent investigations,regulating material composition,changing the preweld heat treatment of the base metal,optimizing the welding process parameters,and applying auxiliary control methods are effective strategies for mitigating cracks.To promote the application of nickel-based superalloys,further research on the combination impact of multiple elements on cracking prevention and specific quantitative criteria for liquation cracking is necessary.

关键词： nickel-based superalloy fusion welding liquation cracking cracking mechanism cracking suppression

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