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Turbulence Statistics of Thermo-Buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： SUN Feng xie Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection *** existence of buoyancy force would lead to strongly anisotropic flow and thermal transport *** is closely related to the cooling performance of the *** elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence *** results indicated that the buoyancy and inertial force together dominated the change of turbulent ***,the spatial thermal buoyancy effect significantly suppressed the vertical velocity *** is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal *** the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,*** the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more *** thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer *** results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics

Transfer learning framework for multi-scale crack type classification with sparse microseismic networks

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International Journal of Mining Science and Technology 2024年第2期34卷 167-178页

作者： Arnold Yuxuan xie Bing QLi department of Civil and Environmental Engineering Western UniversityLondon N6A 3K7Canada

Rock fracture mechanisms can be inferred from moment tensors(MT)inverted from microseismic ***,MT can only be inverted for events whose waveforms are acquired across a network of *** is limiting for underground mines where the microseismic stations often lack azimuthal ***,there is a need for a method to invert fracture mechanisms using waveforms acquired by a sparse microseismic ***,we present a novel,multi-scale framework to classify whether a rock crack contracts or dilates based on a single *** framework consists of a deep learning model that is initially trained on 2.00000+manually labelled field-scale seismic and microseismic waveforms acquired across 692.*** learning is then applied to fine-tune the model on 300000+MT-labelled labscale acoustic emission waveforms from 39 individual experiments instrumented with different sensor layouts,loading,and rock types in *** optimal model achieves over 86%F-score on unseen waveforms at both the lab-and *** model outperforms existing empirical methods in classification of rock fracture mechanisms monitored by a sparse microseismic *** facilitates rapid assessment of,and early warning against,various rock engineering hazard such as induced earthquakes and rock bursts.

关键词： Multi-scale Fracture processes Microseismic Acoustic emission Source mechanism Deep learning

Effects of Aromatherapy on Physical and Mental Health of Cancer Patients Undergoing Radiotherapy and/or Chemotherapy: A Meta-Analysis

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Chinese Journal of Integrative Medicine 2024年第5期30卷 449-457页

作者： xie Shuang-ran MA Liang XU Xin-yu ZHOU Shu xie Hui-miao xie Chang-sheng The First Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053China department of Medical Oncology Hangzhou Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medical UniversityHangzhou 310007China department of Dermatology the Third Xiangya HospitalCentral South UniversityChangsha 410013China department of Famous Chinese Medicine Clinic the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310005China department of Medical Oncology the First Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310006China

Backgroup:Currently,aromatherapy is being increasingly utilized in clinical practice,particularly in managing the side effects associated with radiotherapy and ***,it remains to be established whether aromatherapy can effectively alleviate these ***:To investigate the effects of aromatherapy on the physical and mental health of patients with cancer undergoing radiotherapy and ***:Seven databases were researched from inception until September 2.,2.2.,including PubMed,Scopus,and Web of Science,Chinese National Knowledge Infrastructure,Wanfang database,China Biology Medicine disc and VIP Chinese Medical Journal *** Manager version 5.3 was utilized for data *** Cochrane Risk of Bias tool RoB2.was employed to evaluate the quality of the literature included in the *** quality rating was assessed using the Grading of Recommendations Assessment,Development,and Evaluation(GRADE) approach through the GRADEpro GDT online ***:Nineteen studies involving 1,541 patients were *** can alleviate nausea [relative risk(RR)=0.64,95% confidence interval(CI):0.53 to 0.78,P2.=46%;standardized mean difference(SMD)=-0.86,95% CI:-1.2. to-0.51,P2.=64%] and vomiting(RR=0.54,95% CI:0.42.to 0.69,P2.=35%;SMD=-1.2.,95% CI:-1.52.to-1.03,P2.=92.),improve sleep disorders [mean difference(MD)=-3.39,95% CI:-3.95 to-2.84,P2.=0%],relieve pain(SMD=-1.58,95% CI:-1.96 to-1.2.,P2.=0%),mitigate fatigue(SMD=-1.2.,95% CI:-2.44 to-0.11,P2.=93%) and enhance quality of life(SMD=0.50,95% CI:0.2. to 0.79,P2.=0%) in cancer patients after radiotherapy and chemotherapy,but it may not have a significant effect on *** risk of bias was high in the included studies using the Cochrane Risk of Bias tool RoB2.and no studies were considered to be of high grade according to the GRADE ***:Aromatherapy is an efficacious,safe a

关键词： aromatherapy cancer chemoradiotherapy physical psychological

Phonon-blockade-based multiple-photon bundle emission in a quadratically coupled optomechanical system

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Frontiers of physics 2024年第3期19卷 207-215页

作者： Ye-Jun Xu Hong xie Interdisciplinary Research Center of Quantum and Photoelectric Information Chizhou UniversityChizhou 247000China department of mathematics and Physics Fujian Jiangxia UniversityFuzhou 350108China

We propose a scheme to realize antibunched multiple-photon bundles based on phonon blockade in a quadratically coupled optomechanical *** adjusting the detunings to match the conditions of phonon blockade in the photon sidebands,we establish super-Rabi oscillation between zero-photon state and multiple-photon states with adjustable super-Rabi frequencies under appropriate single-phonon resonant *** the system dissipation into account,we numerically calculate the standard and generalized second-order functions of the cavity mode as well as the quantum trajectories of the state populations with Monte Carlo simulation to confirm that the emitted photons form antibunched multiple-photon ***,the desirable n-photon states are reconstructed after a direct phonon emission based on phonon blockade,and thus the single-phonon emission heralds the cascade emission of n-photon *** proposal shows that the optomechanical system can simultaneously behave as antibunched multiple-photon emitter and single-phonon *** a nonclassical source could have potential applications in quantum information science.

关键词： multiple-photon bundle emission phonon blockade optomechanical system

Maxima with random indexes

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Chinese Science Bulletin 1997年第21期42卷 1767-1771页

作者： xie shengrong{2. of mathematics, southwest China normal university, chongqing 630715, China department of mathematics Southwest China Normal University Chongqing China

LET {ξi} be a sequence of random variables and Mn = =V ξi, which connect asymptoticallysome regularly varying functions. Let {Nn} be a sequence of nonnegative integer-valued ran-dom variables. In this note the limit... 详细信息

关键词： regularly varying function maximum random index.

Visible-Light-Promoted Palladium-Catalyzed Cross-Coupling of lodocarboranes with Disulfides and Phenylselenyl Chloride

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Chinese Journal of Chemistry 2024年第2期42卷 129-134页

作者： Shimeng Li Yizhen Liu Zuowei xie Shenzhen Grubbs Institute and department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China

This work describes a general method for the synthesis of a series of sulfenylated and selenylated carboranes at room temperature using readily available iodocarboranes as starting materials via boron-centered carboranyl *** hypervalent boron radicals are generated by a visible-light-promoted Pd(O)/Pd(I)*** are useful intermediates and can be trapped by disulfides and phenylselenyl chloride for the convenient construction of B-S/Sebonds.

关键词： Carborane Sulfenylation Selenylation B-I activation Radical Photocatalysis Boron Selectivity

Mega-Constellations Based TT&C Resource Sharing: Keep Reliable Aeronautical Communication in an Emergency

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China Communications 2024年第2期21卷 1-16页

作者： Haoran xie Yafeng Zhan Jianhua Lu department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

With the development of the transportation industry, the effective guidance of aircraft in an emergency to prevent catastrophic accidents remains one of the top safety concerns. Undoubtedly, operational status data of the aircraft play an important role in the judgment and command of the Operational Control Center(OCC). However, how to transmit various operational status data from abnormal aircraft back to the OCC in an emergency is still an open problem. In this paper, we propose a novel Telemetry, Tracking,and Command(TT&C) architecture named Collaborative TT&C(CoTT&C) based on mega-constellation to solve such a problem. CoTT&C allows each satellite to help the abnormal aircraft by sharing TT&C resources when needed, realizing real-time and reliable aeronautical communication in an emergency. Specifically, we design a dynamic resource sharing mechanism for CoTT&C and model the mechanism as a single-leader-multi-follower Stackelberg game. Further, we give an unique Nash Equilibrium(NE) of the game as a closed form. Simulation results demonstrate that the proposed resource sharing mechanism is effective, incentive compatible, fair, and reciprocal. We hope that our findings can shed some light for future research on aeronautical communications in an emergency.

关键词： aeronautical emergency communication mega-constellation networked TT&C resource allocation stackelberg game

A brief review on the recent development of phonon engineering and manipulation at nanoscales

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International Journal of Extreme Manufacturing 2024年第1期6卷 177-206页

作者： Siqi xie Hongxin Zhu Xing Zhang Haidong Wang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China

Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat fow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting *** work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices,and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.

关键词： phonon engineering phononic device nanoscale

Tailoring MXene Thickness and Functionalization for Enhanced Room‑Temperature Trace NO_(2. Sensing

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Nano-Micro Letters 2024年第5期16卷 71-86页

作者： Muhammad Hilal Woochul Yang Yongha Hwang Wanfeng xie department of Physics Dongguk UniversitySeoul 04620Republic of Korea department of Control and Instrumentation Engineering Korea UniversitySejong 30019Republic of Korea School of Electronics&Information University‑Industry Joint Center for Ocean Observation and Broadband CommunicationQingdao UniversityQingdao 266071China

In this study,precise control over the thickness and termination of Ti3C2.X MXene flakes is achieved to enhance their electrical properties,environmental stability,and gas-sensing *** a hybrid method involving high-pressure processing,stirring,and immiscible solutions,sub-100 nm MXene flake thickness is achieved within the MXene film on the *** control is achieved by defunctionalizing MXene at 650℃ under vacuum and H2.gas in a CVD furnace,followed by refunctionalization with iodine and bromine vaporization from a bubbler attached to the ***,the introduction of iodine,which has a larger atomic size,lower electronegativity,reduce shielding effect,and lower hydrophilicity(contact angle:99°),profoundly affecting *** improves the surface area(36.2.cm^(2. g^(-1)),oxidation stability in aqueous/ambient environments(2. days/80 days),and film conductivity(749 S m^(-1)).Additionally,it significantly enhances the gas-sensing performance,including the sensitivity(0.1119Ωppm^(-1)),response(0.2. and 2.%to 50 ppb and 2.0 ppm NO_(2.),and response/recovery times(90/100 s).The reduced shielding effect of the–I-terminals and the metallic characteristics of MXene enhance the selectivity of I-MXene toward *** approach paves the way for the development of stable and high-performance gas-sensing two-dimensional materials with promising prospects for future studies.

关键词： Controlled MXene thickness Gaseous functionalization approach Lower electronegativity functional groups Enhanced MXene stability Trace NO_(2.sensing