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A Hybrid φ/B-OTDR for Simultaneous Vibration and Strain Measurement

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Photonic Sensors 2016年第2期6卷 121-126页

作者： Fei PENG Xuli CAO Key laboratory of Optical Fiber Sensing & communications (Ministry of Education) University of Electronic Scienceand Technology of China Chengdu 611731 China

A hybrid phase-sensitive optical time domain reflectometry （φ-OTDR） and Brillouin optical time domain reflectometry （B-OTDR） system which can realize simultaneous measurement of both dynamic vibration and static strain is proposed. Because the Rayleigh scattering light and spontaneous Brilliouin scattering light are naturally frequency-multiplexed, the heterodyne asynchronous demodulation of frequency shift keying （FSK） in optical fiber communications is utilized, and the demodulations of the two scattering signals are synchronized. In addition, the forward Raman amplification is introduced to the system, which not only makes up for the deficiency of spontaneous BriUiouin scattering based distributed fiber sensor, but also has the merit of the single end measurement of B-OTDR. The designed φ/B-OTDR hybrid system has the sensing range of 49km with 10m spatial resolution. The vibration and strain experiments show that this hybrid system has great potential for use in long-distance structural health monitoring.

关键词： Optical fiber sensor Rayleigh scattering Brillouin scattering vibration strain

Mu-Xiang-You-Fang protects PC12 cells against OGD/R-induced autophagy via AMPK/mTOR signaling pathway

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中国药理学与毒理学杂志 2019年第9期33卷 742-743页

作者： MA Hui-xia CHEN Ai-ling HOU Fan LI Ting-ting ZHU Ya-fei ZHAO Qi-peng Key laboratory of modern Hui Medicine Ningxia Medical UniversityYinchuan 750004China Department of Pharmacology Ningxia Medical UniversityYinchuan 750004China

OBJECTIVE Mu-Xiang-You-Fang(MXYF)is a classic prescription of Hui medicine,composed of five herbs,which has been used to treat ischemic stroke for many ***,the potential pharmacological mecha⁃nisms of MXYF remain *** present research is to investigate the neuroprotective effect of MXYF and its role in modulating autophagy via AMPK/mTOR signaling pathway in the PC12 oxygen-glucose deprivation and reperfusion(OGD/R)injury *** MXYF was extracted by supercritical CO2 fluid extraction ***12 OGD/R injury model was established by oxygen-glucose deprivation for 2 h and reperfusion for 24 *** effects of MXYF on the viability and cytotoxicity of PC12 cells were determined through cell counting kit(CCK-8)*** method was performed to determine the LDH leakage *** calcium concentration was determined by chemical fluorescence method and the mitochondrial membrane potential was determined through flow ***(MDC)staining was conducted to detect autophagosome *** expression of LC3,Beclin1,p62,p-AMPK,ULK1,p-mTOR and p-p70s6k proteins were determined by immunofluorescence and Western blotting *** MXYF(1,2 and 4 mg·L^-1)could significantly increase the cell viability and mitochondrial membrane potential,while decreased the release of lactate dehydrogenase(LDH)and calcium concentration in PC12 *** studies showed that MXYF reduced the LC3-II/LC3-I ratio and inhibited the expression of beclin1,p-AMPK and *** comparison,the expres⁃sion of p-mTOR,p-p70s6k and p62 were significantly *** MXYF inhibits autophagy after OGD/Rinduced PC12 cell injury through AMPK-mTOR pathway,thus MXYF might have therapeutic potential for treating the ischemic stroke.

关键词： Mu-Xiang-You-Fang PC12 cells oxygen-glucose deprivation and reperfusion autophagy AMPK/mTOR pathway

Flocking fragmentation formulation for a multi-robot system under multi-hop and lossy ad hoc networks

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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1057-1076页

作者： Silan LI Shengyu ZHANG Tao JIANG The Research Center of 6G Mobile communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Wuhan national laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

We investigate the impact of network topology characteristics on focking fragmentation for a multi-robot system under a multi-hop and lossy ad hoc network,including the network's hop count features and information's successful transmission probability(STP).Specifically,we first propose a distributed communication calculation execution protocol to describe the practical interaction and control process in the ad hoc network based multi-robot system,where focking control is realized by a discrete-time Olfati-Saber model incorporating STP-related ***,we develop a fragmentation prediction model(FPM)to formulate the impact of hop count features on fragmentation for specific focking *** model identifies the critical system and network features that are associated with *** considering general focking scenarios affected by both hop count features and STP,we formulate the flocking fragmentation probability(FFP)by a data fitting model based on the back propagation neural network,whose input is extracted from the *** FFP formulation quantifies the impact of key network topology characteristics on fragmentation *** results verify the effectiveness and accuracy of the proposed prediction model and FFP formulation,and several guidelines for constructing the multi-robot ad hoc network are concluded.

关键词： Multi-robot flocking Flocking fragmentation probability Fragmentation prediction Multi-robot communication networks

SPECTRUM HANDOFF IN COGNITIVE RADIO WITH FUZZY LOGIC CONTROL

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Journal of Electronics(China) 2010年第5期27卷 708-714页

作者： Tang Wanbin Peng Dong national Communication laboratory University of Electronic Science and Technology of China Chengdu 611731China

The secondary usage of spectrum has been investigated in Cognitive Radio(CR) network to resolving the spectrum scarcity issue in wireless *** Primary Users(PU) who own the spectrum appear,spectrum handoff is needed to maintain the communications of Secondary *** the decision making of spectrum handoff is a challenge issue for CR network,because the input of decision making,which obtain through spectrum sensing,is heterogeneous and *** this paper we will use fuzzy logic control theory to solve this issue and make use of new information for handoff operation:the probability of PU's occupancy at a certain *** new algorithm can make more intelligent decision compared to simple traditional spectrum handoff decision making and reduce the probability of spectrum handoff,also the performance of SU's communication can be enhanced.

关键词： Cognitive Radio (CR) Spectrum handoff Fuzzy logic control

Extracellular vesicles loaded dual-network bioactive sealant via immunoregulation and annulus fibrosus repair for intervertebral disc herniation

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Journal of Materials Science & Technology 2024年第17期184卷 75-87页

作者： Zetao Wang Haofei Li Huitong Luo Hao Wang Zemin Ling Dafu Chen Qi Feng Xiaodong Cao School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China national Engineering Research Centre for Tissue Restoration and Reconstruction Guangzhou 510006China School of Medicine South China University of TechnologyGuangzhou 510006China Key laboratory of Biomedical Engineering of Guangdong Province South China University of TechnologyGuangzhou 510006China Key laboratory of Biomedical Materials and Engineering of the Ministry of Education South China University of TechnologyGuangzhou 510006China Zhongshan Institute of modern Industrial Technology of SCUT Guangdong 528437China Guangdong Provincial Key laboratory of Orthopedics and Traumatology Department of Spinal SurgeryThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China laboratory of Bone Tissue Engineering Beijing Laboratory of Biomedical MaterialsBeijing Research Institute of Orthopaedics and TraumatologyBeijing JiShuiTan HospitalBeijing 100035China

Intervertebral disc herniation(IVDH)is a common manifestation of intervertebral disc degeneration(IVDD)characterized by inflammation that results in the rupture of the annulus fibrosus(AF)and her-niation of the nucleus pulposus(NP).While current clinical research primarily focuses on regulating the degenerative NP,the crucial role of the AF in maintaining the mechanical stability and metabolic balance of the intervertebral disc(IVD)has been *** immunoregulation and AF repair is im-perative to effectively prevent recurrent ***,this study introduces a bioactive sealant(OD/GM/QCS-sEVs),which combines gelatin methacryloyl(GM)and oxidized dextran(OD)with quater-nized chitosan(QCS)and incorporates small extracellular vesicles(sEVs).The developed sealant possesses injectability,self-healing capabilities,tissue adhesiveness,and mechanical stability,with an average ad-hesive strength of 109.63 *** vitro experiments demonstrate that OD/GM/QCS-sEVs effectively seal AF defects while preserving mechanical properties comparable to those of a normal ***,the sealant releases sEVs through a pH-responsive mechanism,thereby modulating macrophage polarization to the M2 phenotype via the NF-κB signaling *** mechanism facilitates immunoregulation and anti-inflammatory effects,and promotes stem cell differentiation into *** experiments confirm the ability of OD/GM/QCS-sEVs to seal defects,prevent proteoglycan loss,inhibit IVDD develop-ment,and promote AF ***,OD/GM/QCS-sEVs hold promise as an innovative bioactive sealant for recurrent herniation by resolving immunoregulation and AF regeneration.

关键词： Intervertebral disc herniation Extracellular vesicles Double-network hydrogel Sealant Immunoregulation

Analysis of the microstructural evolution and oxidation behavior of NiCoCrAlYTa coating at high temperature

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Analysis of the microstructural evolution and oxidation beha...

Nucleation growth quenching for superior cluster catalysts

第四届粤港澳大湾区真空科技创新发展论坛暨2020年广东省真空学会学术年会

作者：杨洪志 Jian-Peng Zou Qian Shi Di Wang Ming-Jiang Dai Song-Sheng Lin State Key laboratory of Powder Metallurgy Central South University The Key Lab of Guangdong for modern Surface Engineering Technology National Engineering Laboratory for Modern Materials Surface Engineering TechnologyInstitute of New MaterialsGuangdong Academy of Sciences

NiCoCrAlYTa coating was synthesized successfully onto a Ni-based superalloy by arc ion plating(AIP) *** that,the vacuum heat treatment was carried out and the coating was then subjected to isothermal oxidation in air at 1050℃ for up to 200 *** microstructural evolution and interface diffusion behavior were studied systematically using electron backscattered diffraction(EBSD),electron probe micro-analyzer(EPMA) combined with other characterization methods,such as scanning electron microscopy(SEM),X-ray diffraction(XRD) and energy-dispersive spectroscope(EDS).The results revealed that the coating was primarily composed of γ-Ni and γ’-Ni Al *** oxidation process,the oxides scale is predominantly composed of α-Al O with Y-rich oxide and Cr O irregularly *** the content of Al was gradually consumed,which contributed the microstructural change,resulting in Al-depleted zone(ADZ).The thickness of the oxides scale after oxidation for 100 h and 200 h was 1.53 μm and 3.75 pm,***,the oxidation kinetic curve of NiCoCrAlYTa coating conformed to the parabolic law,which indicating the coating has good oxidation resistance with the formation of a continuously dense α-Al O on the *** diffusion coefficient of typical elements was calculated by using Boltzmann-Matano ***,thermodynamic and oxidation kinetic analysis of NiCoCrAlYTa coating were carried out to provide in-depth understanding of the microstructure evolution and oxidation behavior.

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Nano Research 2022年第9期15卷 7933-7939页

作者： Ruyue Wang Feng Cheng Yonggang Wang Dongyu Fan Bohan Deng Yuanzheng Long Haolin Tang Kai Huang Zhaowei Qu Ming Lei Binghui Ge Hui Wu State Key laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China State Key laboratory of Information Photonics and Optical communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China State Key laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Key laboratory of Space-ground Interconnection and Convergence Beijing University of Posts and Telecommunications(BUPT)Beijing 100876China Information Materials and Intelligent Sensing laboratory of Anhui Province Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China

Cluster catalysts are rapidly growing into an important sub-field in heterogeneous catalysis,owing to their distinct geometric structure,neighboring metal sites,and unique electronic *** the thermodynamics and kinetics of the formation of nanoparticles have been largely investigated,the precise synthesis of clusters in wet chemical methods still faces great *** the study,a quenching strategy of asymmetric temperature in solution for the rapid generation of vacancy-defect rich clusters is *** quenching process can be used to synthesize multitudinous metal compound clusters,including metal oxides,fluorides,oxygen-sulfur compounds,and *** oxygen evolution reaction(OER),IrO_(2)clusters with abundant oxygen vacancies were obtained and uniformly dispersed in the *** to commercial IrO_(2),the prepared IrO_(2)cluster can be directly loaded on carbon paper and used as binder-free electrodes,which exhibit higher OER activity and long-term operational stability in alkaline *** quenching strategy provides a simple and efficient method for the synthesis of clusters,which has tremendous potential for industrial-scale preparation and application,especially can be further applied to flow electrochemical generators.

关键词： rapid-chilling cluster structure transition metal compounds binder-free electrode oxygen evolution reaction

Nanoscale materials transformations revealed by liquid phase TEM

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Nano Research 2024年第10期17卷 9152-9165页

作者： Qiubo Zhang Daewon Lee Haimei Zheng Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720USA Department of Materials Science and Engineering University of CaliforniaBerkeleyCalifornia 94720USA

Nanoscale materials often undergo structural,morphological,or chemical changes,especially in solution processes,where heterogeneity and defects may significantly impact the transformation *** phase transmission electron microscopy(TEM),allowing us to track dynamic transformations of individual nanoparticles,has become a powerful platform to reveal nanoscale materials transformation pathways and address challenging issues that are hard to approach by other *** the development of modern liquid cells,implementing advanced imaging and image analysis methods,and strategically exploring diverse systems,significant advances have been made in liquid phase TEM,including improved high-resolution imaging through liquids at the atomic level and remarkable capabilities in handling complex systems and *** the past more than a decade,we spent much effort in developing and applying liquid phase TEM to elucidate how atomic level heterogeneity and defects impact various physicochemical processes in liquids,such as growth,self-assembly of nanoparticles,etching/corrosion,electrodeposition of alkali metals,catalyst restructuring during reactions,and so *** article provides a brief review of the liquid phase TEM study of nanoscale materials transformations,focusing on the growth of nanomaterials with distinct shape/hierarchical structures,such as one-dimensional(1D)growth by nanoparticle attachment,two-dimensional(2D)growth with nanoparticles as intermediates,core-shell structure ripening,solid-liquid interfaces including those in batteries and electrocatalysis,highlighting the impacts of heterogeneity and defects on broad nanoscale transformation pathways.

关键词： liquid phase transmission electron microscopy(TEM) liquid cells nanomaterials growth transformations pathways solid-liquid interface heterogeneity and fluctuations

Review of Real-time Simulation of Power Electronics

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Journal of modern Power Systems and Clean Energy 2020年第4期8卷 796-808页

作者： Fei Li Yichao Wang Fan Wu Yao Huang Yang Liu Xing Zhang Mingyao Ma School of Electrical Engineering and Automation Hefei University of TechnologyHefeiChina national and Local Joint Engineering laboratory for Renewable Energy Access to Grid Technology HefeiChina

Real-time simulation of power electronics has been recognized by the industry as an effective tool for developing power electronic devices and *** there is no energy transfer during the course of the usage,real-time simulation has a lot of advantages in the process of development and *** the perspective of real-time simulation,this paper focuses on the main problems in modeling accuracy,system bandwidth and stability,limitations on communication interface and energy interface,and the cost of platform ***,we provide further research directions.

关键词： Hardware-in-the-loop simulation modeling and simulation of power electronics correction method power interface algorithm numerical method