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Unipolar Resistive Switching Effects Based on Al/ZnO/P^(++)-Si Diodes for Nonvolatile Memory Applications

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Chinese Physics Letters 2012年第8期29卷 205-208页

作者： SHI Wei TAI Qiang XIA Xian-hai YI Ming-Dong xie ling-hai FAN Qu-Li WANG Lian-Hui WEI Ang HUANG Wei Key Laboratory for Organic Electronics&Information Displays and Institute of Advanced Materials Nanjing University of Posts&TelecommunicationsNanjing 210046 Jiangsu-Singapore Joint Research Center for Organic/Bio Electronics&Information Displays Nanjing 210046

Al/ZnO/P^(++)-Si diodes exhibit typical unipolar resistive switching *** electroforming-free characteristics are observed after annealing the ZnO thin film at 400℃ in *** ON/OFF ratios of the resistance are in the range of 104–105 at a very low operation voltage of 0.1 V,and the devices show good endurance characteristics of over 400 cycles with negligible ***,the memory mechanisms of the diodes are proposed on the basis of the current-voltage and resistance-voltage *** results indicate that Al/ZnO/P^(++)-Si devices have potential applications in nonvolatile memory devices.

关键词： diodes Switching resistance

Flow variability along a vegetated natural stream under various sediment transport rates

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Journal of Mountain Science 2018年第11期15卷 2347-2364页

作者： WANG hai-zhou Xu Ze-xing Yu hai-ti WANG xie-kang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The influence of vegetation and sediment on flow characteristics in open channels cannot be neglected. To study the flow variability under the effects of the instream natural vegetation and sediment supply, experiments were conducted with varied water and sediment supply in a movable bed of a river prototype. The instantaneous threedimensional velocities near two types of vegetation patches(the shrub and the weed) and along the centerline of the main channel with vegetation belts were measured using a 3-D side-looking acoustic Doppler velocimetry. The experimental results show that both the instream vegetation and sediment supply strongly affect the flow and turbulence characteristics. In the case of vegetation patches, both the shrub and weed have a considerable influence on the distribution of the streamwise velocity and turbulence intensity of their surrounding water. The streamwise velocity distribution followed as J-shape and linear shape around the weed and shrub under different experimental conditions. The turbulence intensity was large at the top of the weed and shrub;the shrub had its greatest influence on the downstream water flow. In the case of vegetation belts,the streamwise velocity along the centerline of the main channel exhibited an S-shape, J-shape and linear shape at different locations under varied water,vegetation structures and riverbed *** turbulence intensity along the centerline of the main channel ranged from 0.0 to 0.1. The upstream turbulence intensity was affected considerably by a sediment supply, while the downstream turbulence intensity changed with the varied vegetation characteristics and riverbed topography. The second flow coefficient M-value increased longitudinally and was almost positive along the centerline of the main channel, implying that the rotational direction of the secondary current cell was clockwise.

关键词： Natural vegetation Sediment supply Velocity profile Turbulence intensity Secondary flow Movable bed

Nitrogen-doped graphene nanosheets as reactive water purification membranes

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Nano Research 2016年第7期9卷 1983-1993页

作者： Yanbiao Liu ling Yu Choon Nam Ong Jianping xie NUS Environmental Research Institute National University of Singapore 117411 Singapore Department of Chemical and Biomolecular Engineering National University of Singapore 117585 Singapore

Oxidation of organic pollutants by sulfate radicals produced via activation of persulfate has emerged as a promising advanced oxidation technology to address various challenging environmental issues. The development of an effective, environmentally-friendly, metal-free catalyst is the key to this technology. Additionally, a supported catalyst design is more advantageous than conventional suspended powder catalysts from the point of view of mass transfer and practical engineering applications （e.g. post-use separation）. In this study, a metal-free N-doped reduced graphene oxide （N-rGO） catalyst was prepared via a facile hydrothermal method. N-rGO filters were then synthesized by facile vacuum filtration, such that water can flow through nanochannels within the filters. Various advanced characterization techniques were employed to obtain structural and compositional information of the as-synthesized N-rGO filters. An optimized phenol oxidative flux of 0.036 ＋_ 0.002 mmol.h ~ was obtained by metal-flee catalytic activation of persulfate at an influent persulfate concentration of 1.0 mmol-L 1 and filter weight of 15 rag, while a N-free rGO filter demonstrated negligible phenol oxidation capability under similar conditions. Compared to a conventional batch system, the flow-through design demonstrates obviously enhanced oxidation kinetics （0.036 vs. 0.010 retool-h-I）, mainly due to the liquid flow through the filter leading to convection-enhanced transfer of the target molecule to the filter active sites. Overall, the results exemplified the advantages of organic compound removal by catalytic activation of persulfate using a metal-free catalyst in flow- through mode, and demonstrated the potential of N-rGO filters for practical environmental applications.

关键词： persulfate activation nitrogen-doped graphene phenol oxidation convective flow batch system

Penicillin G acylase-responsive near-infrared fluorescent probe:Unravelling biofilm regulation and combating bacterial infections

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Chinese Chemical Letters 2024年第11期35卷 423-429页

作者： Yang Liu Leilei Zhang Kaixuan Liu ling-ling Wu hai-Yu Hu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Beijing Key Laboratory of Active Substance Discovery and Druggability EvaluationInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Antibiotic resistance poses a critical threat to human healthcare,largely driven by bacterial *** biofilms resist the immune system and antibiotics,rendering enclosed microbial cells 10-1000times more antibiotic-resistant than planktonic cells,leading to severe ***,there is an urgent need to develop innovative tools for investigating biofilm regulators and devising novel antibacterial *** this study,we developed Cy-NEO-PA,a near-infrared(NIR)fluorescent probe responsive to penicillin G acylase(PGA),with bacteria-targeting *** probe was designed to visualize the influence of environmental factors on biofilm formation in Acinetobacter baumannii(***).Our findings demonstrated that glucose suppressed PGA production,leading to enhanced biofilm formation,whereas phenylacetic acid(PAA)stimulated PGA production and inhibited biofilm formation in *** observations highlight the remarkable capability of Cy-NEO-PA to accurately measure PGA dynamics,shedding light on the critical role of PGA in biofilm ***,Cy-NEO-PA exhibited excellent biocompatibility,potent reactive oxygen species(ROS)generation,efficient photothermal conversion,and bacteria-targeting abilities,making it a promising agent for combating bacterial infections and promoting wound healing through photothermal(PTT)/photodynamic(PDT)*** discoveries emphasize the significant role of PGA in antibacterial therapy and offer valuable insights for the design of effective strategies targeting PGA to combat biofilm-associated infections.

关键词： Penicillin G acylase Phototherapy Biofilm regulation Wound healing Photothermal Photodynamic

Study on the Synthesis and Antitumor Activity of New Indolocarbazole Compounds

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Chinese Journal of Structural Chemistry 2016年第2期35卷 205-211页

作者： ZHAO ling-ling Zhai Fu-Min xie Ming-Chao QI Ganga Department of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China Jiangsu Wanquan Pharmaceutical Biotechnology Company Taizhou 225300China Binhai County Safety Supervision Bureau Yancheng 224500China

A series of new antitumor compounds having indolecarbazole structures were designed and synthesized. The methoxy substituted indolecarbazole parent nucleus, which was firstly synthesized, is condensed with bromine substituted amino acid methyl ester to produce the target compounds. The target compounds were performed with methylthiazolyldiphenyl-tetrazolium bromide（MTT） in vitro cytotoxin activity test and the results showed that compounds CZ-1, CZ-3 and CZ-6 have higher activity against human colon cancer（HT-29） and（HCT-8）, hepatocellular carcinoma（Bel-7402）, NSCLC（A549） and breast cancer（MCF-7） cells as compared to the positive control JDC-108.

关键词： indolecarbazole antitumor activity cytotoxin activity

Study on the System for Separating Sulfurfrom Flue Gas and Dust

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Journal of Systems Engineering and Electronics 2000年第4期11卷 73-79页

作者： Guo Jinji Zhan Sheng Chen hai xie Xushi Dept. of Applied Mechanics and Engineering Zhongshan UniversityGuangzhou 510275 P. R. China

This paper describes the structure of the system for separating sulfur from flue gas and dust. In the paper, the velocities of turbulent flow and laminar flow inside the tower, the total of liquid membrance, and the additional flow of rotation fogged fluid are calculated, and the separation of rotation air-solid affected by tower is analyzed. The velocity distribution in quasi free vortex area is obtained from experiment. The minimum separated particle diameter is computed. The paper also studies the chemical reactions of flue gas containing sulfide with the dynamic fogged sulfur separating agent and discusses the main factors related to the effect of separating sulfur and dust. At last, the applications of separating sulfur in industrial stove and collecting dust in environmental engineering are introduced.

关键词： Dust Flue gases Laminar flow Liquid membranes Particle size analysis Separation Turbulent flow

A review on co-pyrolysis of coal and oil shale to produce coke

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Frontiers of Chemical Science and Engineering 2020年第4期14卷 504-512页

作者： Xiangchun Liu Ping Cui Qiang ling Zhigang Zhao Ruilun xie Anhui Key Laboratory of Coal Clean Conversion and Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa'anshanAnhui 243002China

It has become the top priority for coking industry to rationally use and enlarge coking coal resources because of the shortage of the *** review focuses on the potential utilization of oil shale(OS)as a feedstock for coal-blending coking,in which the initial and basic step is ***,OS has a high ash *** such OS is directly used for coal-blending coking,the coke product will not meet market ***,this review firstly summarizes separation and beneficiation techniques for organic matter in OS,and provides an overview on coal and OS pyrolysis through several viewpoints(e.g.,pyrolysis process,phenomena,and products).Then the exploratory studies on co-pyrolysis of coal with OS,including co-pyrolysis phenom-ena and process mechanism,are ***,co-pyrolysis of different ranks of coals with OS in terms of coal-blending coking,where further research deserves to be performed,is suggested.

关键词： coal oil shale co-pyrolysis coal blending coking coke

A Novel Wake Oscillator Model for Vortex-Induced Vibrations Prediction of A Cylinder Considering the Influence of Reynolds Number

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China Ocean Engineering 2018年第2期32卷 132-143页

作者： GAO Xi-feng xie Wu-de XU Wan-hai BAI Yu-chuan ZHU hai-tao State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Collaborative Innovation Centre for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

It is well known that the Reynolds number has a significant effect on the vortex-induced vibrations(VIV) of cylinders. In this paper, a novel in-line(IL) and cross-flow(CF) coupling VIV prediction model for circular cylinders has been proposed, in which the influence of the Reynolds number was comprehensively considered. The Strouhal number linked with the vortex shedding frequency was calculated through a function of the Reynolds number. The coefficient of the mean drag force was fitted as a new piecewise function of the Reynolds number, and its amplification resulted from the CF VIV was also taken into account. The oscillating drag and lift forces were modelled with classical van der Pol wake oscillators and their empirical parameters were determined based on the lock-in boundaries and the peak-amplitude formulas. A new peak-amplitude formula for the IL VIV was developed under the resonance condition with respect to the mass-damping ratio and the Reynolds number. When compared with the results from the experiments and some other prediction models, the present model could give good estimations on the vibration amplitudes and frequencies of the VIV both for elastically-mounted rigid and long flexible cylinders. The present model considering the influence of the Reynolds number could generally provide better results than that neglecting the effect of the Reynolds number.

关键词： vortex-induced vibrations Reynolds number wake oscillator model cylinder

Seismic response and correlation analysis of a pile-supported wharf to near-fault pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 883-897页

作者： Wang Jianfeng Su Lei xie Libo ling Xianzhang Ju Peng School of Civil Engineering Qingdao University of TechnologyQingdao 266500China School of Civil Engineering Harbin Institute of TechnologyHarbin 150006China No.2 Engineering Company Ltd.of CCCC First Harbor Engineering Company Ltd Qingdao 266071China

Earthquake investigations have shown that near-fault pulse-like(NF-P)ground motions have unique characteristics compared to near-fault non-pulse-like(NF-NP)and far-field(FF)ground *** is necessary to study the seismic response of pile-supported wharf(PSW)structures under NF-P ground *** this study,a three-dimensional finite element numerical model is created to simulate a *** imparting three types of ground motion,the engineering demand parameters(EDPs)of PSW under NF-P ground motions were analyzed and compared,in which EDPs are the maximum displacement and bending moment of the *** intensity measures(IMs)were selected to characterize the properties of ground *** correlation between IMs and EDPs was *** results show that the piles present larger displacement and bending moment under NF-P ground motions compared to NF-NP and FF ground *** of the IMs have a high correlation with EDPs under NF-P ground motions,and these IMs are more applicable to FF ground *** correlation coefficients between EDPs and IMs under three types of ground motion were obtained,which will provide a valuable reference for the seismic design of PSWs.

关键词： pile-supported wharf correlation analysis near-fault pulse-like ground motion intensity measure seismic response