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Electrically-driven ultrafast out-of-equilibrium light emission from hot electrons in suspended graphene/hBN heterostructures

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International Journal of Extreme Manufacturing 2024年第1期6卷 328-338页

作者： Qiang Liu Wei Xu Xiaoxi Li Tongyao Zhang Chengbing qin Fang Luo Zhihong Zhu shiqiao qin Mengjian Zhu Kostya s Novoselov College of Advanced Interdisciplinary studies&Hunan Provincial Key Laboratory of Novel Nano-optoelectronic Information Materials and Devices National University of Defense TechnologyChangshaHunan 410073People’s Republic of China Nanhu Laser Laboratory National University of Defense TechnologyChangshaHunan 410073People’s Republic of China state Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006People’s Republic of China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006People’s Republic of China state Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006People’s Republic of China Institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Department of Materials science and Engineering National University of SingaporeSingapore 117575Singapore

Nanoscale light sources with high speed of electrical modulation and low energy consumption are key components for nanophotonics and optoelectronics.The record-high carrier mobility and ultrafast carrier dynamics of graphene make it promising as an atomically thin light emitter which can be further integrated into arbitrary platforms by van der Waals forces.However,due to the zero bandgap,graphene is difficult to emit light through the interband recombination of carriers like conventional semiconductors.Here,we demonstrate ultrafast thermal light emitters based on suspended graphene/hexagonal boron nitride(Gr/hBN)heterostructures.Electrons in biased graphene are significantly heated up to 2800 K at modest electric fields,emitting bright photons from the near-infrared to the visible spectral range.By eliminating the heat dissipation channel of the substrate,the radiation efficiency of the suspended Gr/hBN device is about two orders of magnitude greater than that of graphene devices supported on siO2or hBN.Wefurther demonstrate that hot electrons and low-energy acoustic phonons in graphene are weakly coupled to each other and are not in full thermal equilibrium.Direct cooling ofhigh-temperature hot electrons to low-temperature acoustic phonons is enabled by the significant near-field heat transfer at the highly localized Gr/hBN interface,resulting in ultrafast thermal emission with up to 1 GHz bandwidth under electrical excitation.It is found thatsuspending the Gr/hBN heterostructures on the siO2trenches significantly modifies the light emission due to the formation of the optical cavity and showed a~440%enhancement inintensity at the peak wavelength of 940 nm compared to the black-body thermal radiation.The demonstration of electrically driven ultrafast light emission from suspended Gr/hBNheterostructures sheds the light on applications of graphene heterostructures in photonicintegrated circuits,such as broadband light sources and ultrafast thermo-optic phase modulators.

关键词： suspended graphene ultrafast light emitter van der Waals heterostructures thermal radiation electron–phonon interaction

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Effects and mechanisms of acupuncture on women related health

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Frontiers of Medicine 2024年第1期18卷 46-67页

作者： Huichao qin Jiaxing Feng Xiaoke Wu Department of reproductive Medicine Heilongjiang Provincial HospitalHarbin Institute of TechnologyHarbin150036China Department of Obstetrics and Gynecology First Affiliated HospitalHeilongjiang University of Chinese MedicineHarbin150040China

Globally,public health interventions have resulted in a 30-year increase in women’s life expectancy.However,women’s health has not increased when socioeconomic status is ignored.Women’s health has become a major public health concern,for those women from developing countries are still struggling with infectious and labor-related diseases,and their counterparts in developed countries are suffering from physical and psychological disorders.In recent years,complementary and alternative medicine has attracted wide attentions with regards to maintaining women’s health.Acupuncture,a crucial component of traditional Chinese medicine,has been used to treat many obstetric and gynecological diseases for thousands of years due to its analgesic and anti-inflammatory effects and its effects on stimulating the sympathetic/parasympathetic nervous system.To fully understand the mechanism through which acupuncture exerts its effects in these diseases would significantly extend the list of available interventions and would allow for more reasonable advice to be given to general practitioners.Therefore,by searching PubMed and CNKI regarding the use of acupuncture in treating obstetric and gynecological diseases,we aimed to summarize the proven evidence of using acupuncture in maintaining women’s health by considering both its effectiveness and the underlying mechanisms behind its effects.

关键词： acupuncture women health clinical efficacy mechanism

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Towards data-efficient mechanical design of bicontinuous composites usinggenerative AI

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 57-64页

作者： Milad Masrouri Zhao qin Department of Civil and Environmental Engineering Syracuse UniversitySyracuseNY 13244USA Laboratory for Multiscale Material Modelling Syracuse UniversitySyracuseNY 13244USA The BioInspired Institute Syracuse UniversitySyracuseNY 13244USA

The distribution of material phases is crucial to determine the composite’s mechanical property.While the full structure-mechanics relationship of highly ordered material distributions can be studied with finite number of cases,this relationship is difficult to be revealed for complex irregular distributions,preventing design of such material structures to meet certain mechanical requirements.The noticeable developments of artificial intelligence(AI)algorithms in material design enables to detect the hidden structure-mechanics correlations which is essential for designing composite of complex structures.It is intriguing how these tools can assist composite design.Here,we focus on the rapid generation of bicontinuous composite structures together with the stress distribution in loading.We find that generative AI,enabled through fine-tuned Low rank Adaptation models,can be trained with a few inputs to generate both synthetic composite structures and the corresponding von Mises stress distribution.The results show that this technique is convenient in generating massive composites designs with useful mechanical information that dictate stiffness,fracture and robustness of the material with one model,and such has to be done by several different experimental or simulation tests.This research offers valuable insights for the improvement of composite design with the goal of expanding the design space and automatic screening of composite designs for improved mechanical functions.

关键词： Generative artificial intelligence stable diffusion Composite design Phase field model Molecular dynamics simulation

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The Coarse l^(p)-Novikov Conjecture and Banach spaces with Property(H)

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Chinese Annals of Mathematics,series B 2024年第2期45卷 193-220页

作者： Huan WANG qin WANG research Center for Operator Algebras School of Mathematical SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of MEA Ministry of Educationand Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,for 1rs show that the coarse l^(p)-Novikov conjecture holds for metric spaces with bounded geometry which are coarsely embeddable into a Banach space with Kasparov-Yu’s Property(H).

关键词： The coarse l^(p)-Novikov conjecture Banach spaces with Property(H) Coarse geometry K-Theory

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Effect of Iron on the stability of rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth science 2024年第2期35卷 504-513页

作者： Tianlei Zhai Fei qin shengxuan Huang shan qin Yu Gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing100871China school of Earth sciences and resources China University of GeosciencesBeijing100083China Beijing synchrotron radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Carbonates are viewed as the principal oxidized carbon carriers during subduction,and thus the stability of subducted carbonates has significant implications for the deep carbon cycle.Here we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to∼34 GPa by in-situ X-ray diffraction and ex-situ raman spectroscopy.At relatively low temperature below∼1500 K,MnCO_(3)breaks down into MnO and CO_(2).Upon heating to∼1800 K,however,the MnCO_(3)-Fe^(0)reactions occur with the formation of Mn_(3)O_(4),Fe^(O)and reduced carbon.A'three-stage'reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox coupling.The results suggest that Fe^(0)can serve as a reductant to greatly affect the stability of rhodochrosite,which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth's mantle conditions,particularly at depths greater than∼250 km.

关键词： deep carbon cycle rhodochrosite reduced mantle diamond formation high pressure tectonics geochemistry

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Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong Hui Li Ya‑qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic processes.We aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese cities.Methods A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in China.Height and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were assessed.results The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒2015.An apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th percentile.The total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,respectively.The total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural areas.Conclusions The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒2015.More attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity stunting

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Efficient Unsupervised Image stitching Using Attention Mechanism with Deep Homography Estimation

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Computers, Materials & Continua 2024年第4期79卷 1319-1334页

作者： Chunbin qin Xiaotian ran school of Artificial Intelligence Henan UniversityZhengzhou450000China

Traditional feature-based image stitching techniques often encounter obstacles when dealing with images lackingunique attributes or suffering from quality degradation. The scarcity of annotated datasets in real-life scenesseverely undermines the reliability of supervised learning methods in image stitching. Furthermore, existing deeplearning architectures designed for image stitching are often too bulky to be deployed on mobile and peripheralcomputing devices. To address these challenges, this study proposes a novel unsupervised image stitching methodbased on the YOLOv8 (You Only Look Once version 8) framework that introduces deep homography networksand attentionmechanisms. Themethodology is partitioned into three distinct stages. The initial stage combines theattention mechanism with a pooling pyramid model to enhance the detection and recognition of compact objectsin images, the task of the deep homography networks module is to estimate the global homography of the inputimages consideringmultiple viewpoints. The second stage involves preliminary stitching of the masks generated inthe initial stage and further enhancement through weighted computation to eliminate common stitching artifacts.The final stage is characterized by adaptive reconstruction and careful refinement of the initial stitching results.Comprehensive experiments acrossmultiple datasets are executed tometiculously assess the proposed model. Ourmethod’s Peak signal-to-Noise ratio (PsNr) and structure similarity Index Measure (ssIM) improved by 10.6%and 6%. These experimental results confirm the efficacy and utility of the presented model in this paper.

关键词： Unsupervised image stitching deep homography estimation YOLOv8 attention mechanism

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Enhanced Hybrid Equilibrium strategy in Fog-Cloud Computing Networks with Optimal Task scheduling

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Computers, Materials & Continua 2024年第5期79卷 2647-2672页

作者： Muchang rao Hang qin school of Computer science Yangtze UniversityJingzhou434000China

More devices in the Intelligent Internet of Things(AIoT)result in an increased number of tasks that require low latency and real-time responsiveness,leading to an increased demand for computational resources.Cloud computing’s low-latency performance issues in AIoT scenarios have led researchers to explore fog computing as a complementary extension.However,the effective allocation of resources for task execution within fog environments,characterized by limitations and heterogeneity in computational resources,remains a formidable challenge.To tackle this challenge,in this study,we integrate fog computing and cloud computing.We begin by establishing a fog-cloud environment framework,followed by the formulation of a mathematical model for task scheduling.Lastly,we introduce an enhanced hybrid Equilibrium Optimizer(EHEO)tailored for AIoT task scheduling.The overarching objective is to decrease both the makespan and energy consumption of the fog-cloud system while accounting for task deadlines.The proposed EHEO method undergoes a thorough evaluation against multiple benchmark algorithms,encompassing metrics likemakespan,total energy consumption,success rate,and average waiting time.Comprehensive experimental results unequivocally demonstrate the superior performance of EHEO across all assessed metrics.Notably,in the most favorable conditions,EHEO significantly diminishes both the makespan and energy consumption by approximately 50%and 35.5%,respectively,compared to the secondbest performing approach,which affirms its efficacy in advancing the efficiency of AIoT task scheduling within fog-cloud networks.

关键词： Artificial intelligence of things fog computing task scheduling equilibrium optimizer differential evaluation algorithm local search

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stages and Fracture Mechanisms of Lamellar Pearlite of 100-m-Long Differentially Hardened rails Under Long-Term Operation Conditions

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Acta Metallurgica sinica(English Letters) 2018年第12期31卷 1356-1360页

作者： A.A.Yuriev V.E.Gromov V.A.Grishunin Yu.F.Ivanov r.s.qin A.P.semin LTD Evraz-Integrated West siberian MetallurgicalCombine NovokuznetskRussia siberian state Industrial University NovokuznetskRussia National research Tomsk Polytechnic University TomskRussia Institute of High Current Electronics sD rAs TomskRussia school of Engineering and Innovation The Open UniversityWalton HallMilton Keynes MK 7 6AAUK

Using the methods of transmission electron microscopy, the carbide phase evolution in surface layers of the differentiallyquenched rails is studied after the passed tonnage of 691.8 million tons at the depth up to 10 mm along the central axis andfillet of rail head. The action of two mutual supplement mechanisms of steel carbide phase transformation in surface layersat rail operation is established：（1） cutting mechanism of cementite particles with the following departure in the volume offerrite grains or plates （in pearlite structure）; （2） cutting mechanism and following dissolution of cementite particles,transfer of carbon atoms on dislocations （in Cottrell atmospheres and dislocation cores）, transfer of carbon atoms bymoving dislocations into ferrite grains volume （or plates） with the following repeated formation of nanosized cementiteparticles. The first mechanism is accompanied by the change in linear sizes and morphology of carbide particles. Cementiteelement composition change is not essential. Carbide structure change can take place during the second mechanism.

关键词： Cementite Pearlite Fracture rails Mechanisms Operation

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The Multiple roles of Autophagy in Neural Function and Diseases

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Neuroscience Bulletin 2024年第3期40卷 363-382页

作者： Yan-Yan Li Zheng-Hong qin rui sheng Department of Pharmacology and Laboratory of Aging and Nervous Diseases Jiangsu Key laboratory of Neuropsychiatric DiseasesCollege of Pharmaceutical Sciences of Soochow UniversitySuzhou 215123China

Autophagy involves the sequestration and delivery of cytoplasmic materials to lysosomes,where proteins,lipids,and organelles are degraded and recycled.According to the way the cytoplasmic components are engulfed,autophagy can be divided into macroautophagy,microautophagy,and chaperone-mediated autophagy.recently,many studies have found that autophagy plays an important role in neurological diseases,including Alzheimer's disease,Parkinson's disease,Huntington's disease,neuronal excitotoxicity,and cerebral ischemia.Autophagy maintains cell homeostasis in the nervous system via degradation of misfolded proteins,elimination of damaged organelles,and regulation of apoptosis and inflammation.AMPK-mTOr,Beclin 1,TP53,endoplasmic reticulum stress,and other signal pathways are involved in the regulation of autophagy and can be used as potential therapeutic targets for neurological diseases.Here,we discuss the role,functions,and signal pathways of autophagy in neurological diseases,which will shed light on the pathogenic mechanisms of neurological diseases and suggest novel targets for therapies.

关键词： Autophagy Neurodegenerative diseases Cerebral ischemia AMPK mTOr Beclin 1 TP53 Endoplasmic reticulum stress

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