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Chinese Physics B 2018年第9期27卷 128-136页

作者： Zhi-Hua Shao Xue-Guang Qiao Feng-Yi Chen and qiang-zhou rongt School of Physics Northwest UniversityXi an 710069China

An ultrasonic sensitivity-improved fiber-optic Fabry-Perot interferometer （FPI） is proposed and employed for ultra- sonic imaging of seismic physical models （SPMs）. The FPI comprises a flexible ultra-thin gold film and the end face of a graded-index multimode fiber （MMF）, both of which are enclosed in a ceramic tube. The MMF in a specified length can collimate the diverged light beam and compensate for the light loss inside the air cavity, leading to an increased spectral fringe visibility and thus a steeper spectral slope. By using the spectral sideband filtering technique, the collimated FP1 shows an improved ultrasonic response. Moreover, two-dimensional images of two SPMs are achieved in air by recon- structing the pulse-echo signals through using the time-of-flight approach. The proposed sensor with easy fabrication and compact size can be a good candidate for high-sensitivity and high-precision nondestructive testing of SPMs.

关键词： fiber-optic sensor Fabry-Perot interferometer seismic physical model

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying Chen Yinyi Xiong Qin zhou Ling-qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive Science and Transdisciplinary Studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

Recent development in electrode design for wide-temperature supercapacitors

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Science China Chemistry 2025年第1期 96-117页

作者： Jianhong Liu qiang zhou Yuxiao Lin Xinsheng Zhao Guangmin zhou Xiaoxiao Li School of Physics and Electronic Engineering Jiangsu Normal University Tsinghua-Berkeley Shenzhen Institute & Tsinghua Shenzhen International Graduate School Tsinghua University

An ever-increasing market demand has stimulated the soaring enthusiasm of researchers to develop wide-temperature supercapacitors(SCs). The active electrode is one of the most important parts of SC, which is directly related to the energy density,power transmission and long-term cyclability of the device in the wide-temperature environment. Compared with the SC electrodes aimed for room-temperature application, the SC electrodes for operating at wide-temperature scene often face greater challenges. In this review, the main challenges of SC electrodes under various temperature conditions, including low, high and cross-fade temperatures, are summarized. The relevant performance decay and failure mechanisms of wide-temperature SC electrodes are analyzed. In addition, this review deals with the recent studies and developments in robust wide-temperature SC electrodes with respect to the rational design of electrode structures and the exploitation of advanced active materials. Finally, the future directions for exploring reliable wide-temperature SCs are also proposed.

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Exact solution for capillary interactions between two particles with fixed liquid volume

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Applied Mathematics and Mechanics(English Edition) 2016年第12期37卷 1597-1606页

作者： Fengxi zhou qiang MA School of Civil Engineering Lanzhou University of Technology

The capillary interactions, including the capillary force and capillary suction, between two unequal-sized particles with a fixed liquid volume are investigated. The cap- illary interaction model is used within the Young-Laplace framework. With the profile of the meridian of the liquid bridge, the capillary suction, and the liquid volume as state variables, the governing equations with two-fixed-point boundary axe first derived using a variable substitution technique, in which the gravity effects are neglected. The capillary suction and geometry of the liquid bridge with a fixed volume are solved with a shooting method. In modeling the capillary force, the Gorge method is applied. The effects of var- ious parameters including the distance between two particles, the ratio of particle radii, and the liquid-solid contact angles are discussed.

关键词： liquid bridge Young-Laplace equation fixed liquid volume shootingmethod

GluN2B-NMDA receptors in Alzheimer's disease:beyond synapse loss and cell death

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Neural Regeneration Research 2014年第21期9卷 1878-1879页

作者： qiang zhou School of Chemical Biology and Biotechnology Peking University Shenzhen Graduate School

Alzheimer＇s disease （AD） is one of the most devastating dis- eases affecting the life and health of aging population. Two hallmarks of AD are senile plaques and neurofibrillary tan- gles, and AD is well known for the massive loss of neurons and impaired cognitive functions especially memory loss. Despite extensive search for effective treatment, available drugs have limited efficacy without affecting the course of AD. Significant efforts have been devoted to curb the pro- duction of amyloid [3 （A[3; the major component of plaques） or enhance the clearance of it, with the aim to reduce the accumulation of plaque in the brain. Antibodies that can bind A[3 to increase their removal have received a lot of at- tention although recent clinical trial results have been largely negative and disappointing （Panza et al., 2014）. Targets that are not directly related to A[3 have also been pursued. One such target is N-methyl-D-aspartate （NMDA） receptors （NMDARs）, a subclass of glutamate receptors. The antago- nist of NMDAR memantine has been approved for treating moderate to severe AD, although the exact mechanism un- derlying its action is still in debate （Kotermanski and John- son, 2009）.

关键词： GluN2B-NMDA receptors in Alzheimer’s disease NMDA NMDAR

The area minimizing problem in conformal cones,Ⅱ

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Science China Mathematics 2020年第12期63卷 2523-2552页

作者： qiang Gao Hengyu zhou Department of Mathematics Sun Yat-sen UniversityGuangzhou 510275China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory of Analytic Mathematics and Applications Chongqing UniversityChongqing 401331China

In this paper we continue to study the connection among the area minimizing problem,certain area functional and the Dirichlet problem of minimal surface equations in a class of conformal cones with a similar motivation from[15].These cones are certain generalizations of hyperbolic *** describe the structure of area minimizing n-integer multiplicity currents in bounded C^2 conformal cones with prescribed C^1 graphical boundary via a minimizing problem of these area *** an application we solve the corresponding Dirichlet problem of minimal surface equations under a mean convex type *** also extend the existence and uniqueness of a local area minimizing integer multiplicity current with star-shaped infinity boundary in hyperbolic spaces into a large class of complete conformal manifolds.

关键词： area minimizing problem conformal cones mean curvature equation

An approach to the capsule endoscopic robot with active drive motion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 223-231页

作者： Da-qiang GU Yong zhou Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

Commercialized capsule-type endoscopes move passively by peristaltic waves (and gravity),which makes it difficult for doctors to diagnose the areas of interest more thoroughly and *** resolve this problem of passivity,it is necessary to find a special locomotion principle,which fits the gastrointestinal (GI) *** this paper,a legged locomotive mechanism with shape memory alloy (SMA) actuation based on the peristaltic principle is proposed,and then the structure of the locomotion mechanism is *** on the preliminary results,the design,modeling,and fabrication of an SMA microactuation concept for application in an endoscopic capsule are given,as well as the SMA spring and legged component design,which is the core section of the system *** used the pseudo-rigid-body model (PRBM) to analyze nonlinear and large deflections of the SMA legged ***,a prototype endoscope with an SMA spring and six legged components was designed and *** is 15 mm in diameter and 33 mm in total length,with a hollow space to house other parts needed for endoscopy such as a camera,a radio frequency (RF) module,and *** testing,the locomotive mechanism was effective in a plastic tube environment.

关键词： Capsular endoscopy Shape memory alloy (SMA) Microactuation Locomotion

Development of a filtered drag model considering effect of the solid shear rate

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Particuology 2022年第12期71卷 63-74页

作者： Lingxue Wang Ming Jiang qiang zhou School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an710049China Engineering Research Center of New Energy System Engineering and Equipment University of Shaanxi ProvinceXi'an710049China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710049China

This study investigates a 2D gas-solid fast fluidized bed of typical Geldart A particles using highly resolved simulations with two-fluid *** results show that the solid shear rate has a considerable impact on the orientation of the meso-scale structures and hence on the filtered drag *** the basis of the correlation for the filtered drag force established in the literature using the traditional markers(such as filtered solid volume fraction,filtered slip velocity and filter scale),a correction correlated with the solid shear rate in the direction of gravity is proposed for better prediction of the filtered drag *** corrected model is shown to produce improved results in posterior tests of flows in different fluidization regimes including bubbling,turbulent and fast fluidization.

关键词： Gas-solid flows Fluidization Two-fluid model Dimensionless solid shear rate Filtered drag force

Numerical study on two-phase boiling heat transfer performance of interrupted microchannel heat sinks

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Science China(Technological Sciences) 2022年第3期65卷 679-692页

作者： zhou JianHong CHEN XueMei LI qiang MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China

The conventional straight microchannel heat sinks have been reported to inadequately remove the increasing power density of *** recent years,an effective heat transfer enhancement method,flow disruptions have attracted the attention of researchers,where interrupted structures are arranged in the microchannel to enhance flow mixing and heat ***,previous numerical studies of interrupted microchannel heat sinks(I MCHS)mainly focus on single-phase flow condition,and the characteristics of the boiling heat transfer of I MCHS in two-phase flow condition have been rarely ***,the flow and heat transfer characteristics of two I MCHS based on rectangular microchannel heat sink(R MCHS)are investigated by modeling both single-phase and two-phase flow *** two interrupts consist of a combination of cavities and ribs,namely elliptical cavities and elliptical side ribs(EC-ESR),and elliptical cavities and elliptical central ribs(EC-ECR).The results show that for single-phase flow condition,the maximum Nusselt number is increased by 187%in the EC-ESR design and150%in the EC-ECR design compared with the R *** subcooled boiling(i.e.,two-phase flow)condition,the EC-ECR design is a promising structure to enhance boiling heat transfer with 6.7 K reduction of average wall temperature and 29%increment of local heat transfer coefficient when compared with those of R ***,the local heat transfer coefficient in the EC-ESR design is decreased by 22%compared with the R MCHS due to the formation of a rare flow pattern(i.e.,inverted annular flow with vapor film separation)in the *** flow pattern can induce departure from nucleate boiling(DNB),thereby deteriorating the heat transfer on the channel walls.

关键词： microchannel heat sink cavities and ribs thermal performance flow pattern boiling heat transfer flow disruptions

Web-based mixed reality video fusion with remote rendering

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Virtual Reality & Intelligent Hardware 2023年第2期5卷 188-199页

作者： qiang zhou Zhong zhou State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China

Background Mixed reality(MR)video fusion systems merge video imagery with 3D scenes to make the scene more realistic and help users understand the video content and temporal–spatial correlation between them,reducing the user′s cognitive *** video fusion are used in various applications;however,video fusion systems require powerful client machines because video streaming delivery,stitching,and rendering are computationally ***,huge bandwidth usage is another critical factor that affects the scalability of video-fusion *** Our framework proposes a fusion method for dynamically projecting video images into 3D models as *** Several experiments on different metrics demonstrate the effectiveness of the proposed *** The framework proposed in this study can overcome client limitations by utilizing remote ***,the framework we built is based on ***,the user can test the MR video fusion system with a laptop or tablet without installing any additional plug-ins or application programs.

关键词： Mixed reality Video fusion WebRTC Remote rendering