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Chinese Physics Letters 2011年第11期28卷 261-263页

作者： MA Feng WANG Shi-Rong LI Xiang-Gao yan dong-hang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072 State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022

We demonstrate n-type organic thin film transistors(OTFTs)employing copper hexadecafluorophthalocyanine(CuPcF16)as the active layer and para-hexaphenyl(p-6p)as the inducing *** with the CuPcF16-based OTFTs without the𝑝p-6p inducing layer,the performance of the CuPcF16/𝑝p-6p OTFTs is greatly *** charge carrier field-effect mobilityμ,on-off current ratio𝐼Ⅰon/Ⅰoff and threshold voltage𝑉VT of the CuPcF16/p-6p OTFTs are 0.07 cm^(2)/V・s,1.61×105 and 6.28 V,respectively,approaching the level of a single crystal *** improved performance is attributed to the introduction of𝑝p-6p to form a highly oriented and continuous film of CuPcF16 with the molecularπ–πstack direction parallel to the substrate.

关键词： film approaching phthalocyanine

Significant Improvement of Organic Thin-Film Transistor Mobility Utilizing an Organic Heterojunction Buffer Layer

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Chinese Physics Letters 2011年第7期28卷 323-326页

作者： PAN Feng QIAN Xian-Rui HUANG Li-Zhen WANG Hai-Bo yan dong-hang State Key Laboratory of Polymer Chemistry and Physics Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 Graduate School of Chinese Academy of Sciences Beijing 100039

High-mobility vanadyl phthalocyanine(VOPc)/5,5"'−bis(4-fluorophenyl)-2,2':5',2":5",2"'−quaterthiophene(F2-P4T)thin-film transistors are demonstrated by employing a copper hexadecafluorophthalocyanine(F16CuPc)/copper phthalocyanine(CuPc)heterojunction unit,which are fabricated at different substrate temperatures,as a buffer *** highest mobility of 4.08 cm^(2)/Vs is achieved using a F16CuPc/CuPc organic heterojunction buffer layer fabricated at high substrate *** with the random small grain-like morphology of the room-temperature buffer layer,the high-temperature organic heterojunction presents a large-sized fiber-like film morphology,resulting in an enhanced *** the contact resistance of the transistor is significantly reduced and an obvious improvement in device mobility is obtained.

关键词： heterojunction temperature mobility

Adaptive multi-channel Bayesian graph attention network for IoT transaction security

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Digital Communications and Networks 2024年第3期10卷 631-644页

作者： Zhaowei Liu dong yang Shenqiang Wang hang Su School of Computer and Control Engineering Yantai UniversityYantai264005China Department of Electronics Information and BioengineeringPolitecnico di MilanoMilan20133Italy

With the rapid advancement of 5G technology,the Internet of Things(IoT)has entered a new phase of appli-cations and is rapidly becoming a significant force in promoting economic *** to the vast amounts of data created by numerous 5G IoT devices,the Ethereum platform has become a tool for the storage and sharing of IoT device data,thanks to its open and tamper-resistant ***,Ethereum account security is necessary for the Internet of Things to grow quickly and improve people's *** modeling Ethereum trans-action records as a transaction network,the account types are well identified by the Ethereum account classifi-cation system established based on Graph Neural Networks(GNNs).This work first investigates the Ethereum transaction ***,experimental metrics reveal that the Ethereum transaction network is neither optimal nor even satisfactory in terms of accurately representing transactions per *** flaw may significantly impede the classification capability of GNNs,which is mostly governed by their *** work proposes an Adaptive Multi-channel Bayesian Graph Attention Network(AMBGAT)for Ethereum account clas-sification to address this *** uses attention to enhance node features,estimate graph topology that conforms to the ground truth,and efficiently extract node features pertinent to downstream *** extensive experiment with actual Ethereum transaction data demonstrates that AMBGAT obtains competitive performance in the classification of Ethereum accounts while accurately estimating the graph topology.

关键词： Internet of things Graph representation learning Node classification Security mechanism

Spatially selective p-type doping for constructing lateral WS_(2) p-n homojunction via low-energy nitrogen ion implantation

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Light(Science & Applications) 2024年第6期13卷 1159-1169页

作者： Yufan Kang Yongfeng Pei dong He hang Xu Mingjun Ma Jialu yan Changzhong Jiang Wenqing Li Xiangheng Xiao School of Physics and Technology Key Lab of Artificial Micro-and Nano-Structures of Ministry of EducationWuhan UniversityWuhanChina

The construction of lateral p-n junctions is very important and challenging in two-dimensional(2D)semiconductor manufacturing *** researches have demonstrated that vertical p-n junction can be prepared simply by vertical stacking of 2D ***,interface pollution and large area scalability are challenges that are difficult to overcome with vertical stacking *** 2D lateral p-n homojunction is an effective strategy to address these *** selective p-type doping of 2D semiconductors is expected to construct lateral p-n *** this work,we have developed a low-energy ion implantation system that reduces the implanted energy to 300 ***-energy implantation can form a shallow implantation depth,which is more suitable for modulating the electrical and optical properties of 2D ***,we utilize low-energy ion implantation to directly dope nitrogen ions into few-layer WS_(2) and successfully realize a precise regulation for WS_(2) with its conductivity type transforming from n-type to bipolar or even p-type ***,the universality of this method is demonstrated by extending it to other 2D semiconductors,including WSe_(2),SnS_(2) and MoS_(2).Based on this method,a lateral WS_(2) p-n homojunction is fabricated,which exhibits significant rectification characteristics.A photodetector based on p-n junction with photovoltaic effect is also prepared,and the open circuit voltage can reach to 0.39 *** work provides an effective way for controllable doping of 2D semiconductors.

关键词： implantation doping Spatial

Random gradient-free method for online distributed optimization with strongly pseudoconvex cost functions

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Control Theory and Technology 2024年第1期22卷 14-24页

作者： Xiaoxi yan Cheng Li Kaihong Lu hang Xu School of Electrical and Information Engineering Jiangsu UniversityZhenjiang212013JiangsuChina College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao266590ShandongChina

This paper focuses on the online distributed optimization problem based on multi-agent systems. In this problem, each agent can only access its own cost function and a convex set, and can only exchange local state information with its current neighbors through a time-varying digraph. In addition, the agents do not have access to the information about the current cost functions until decisions are made. Different from most existing works on online distributed optimization, here we consider the case where the cost functions are strongly pseudoconvex and real gradients of the cost functions are not available. To handle this problem, a random gradient-free online distributed algorithm involving the multi-point gradient estimator is proposed. Of particular interest is that under the proposed algorithm, each agent only uses the estimation information of gradients instead of the real gradient information to make decisions. The dynamic regret is employed to measure the proposed algorithm. We prove that if the cumulative deviation of the minimizer sequence grows within a certain rate, then the expectation of dynamic regret increases sublinearly. Finally, a simulation example is given to corroborate the validity of our results.

关键词： Multi-agent system Online distributed optimization Pseudoconvex optimization Random gradient-free method

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang Jiang Hui-ting Zheng Fei Liu Hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Predicting the evolution of electrochemical trepanning for inner blisks with a chamfer structure at blade tip

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 560-576页

作者： Jiao, Erhao Zhu, dong Wang, Penghui Zuo, hang Chen, Liyong Nanjing Univ Aeronaut & Astronaut Coll Mech & Elect Engn Nanjing 210016 Peoples R China

Electrochemical trepanning (ECTr) is an effective electrochemical machining (ECM) technique that can be used to manufacture the integral components of aero-engine compressors. This study focused on the dynamic evolution of ECTr for production of inner blisks (bladed disks) with a special chamfer structure at blade tip. Due to the existence of chamfer, the ECTr process of inner blades is in a non-equilibrium state during the early stages, and the physical field changes in the machining gap are complex, making it difficult to predict the forming process. In this paper, a dynamic evolution model (DEM) of inner blade ECTr with a special chamfer at blade tip structure is proposed, and an ECTr multi-physical fields simulation study was carried out. The evolution of the chamfer at blade tip was analyzed and data related to chamfer were predicted based on the dependence of anode boundary properties with machining time and feed rate. In addition, the distributions of current density, electrolyte flow rate, bubble volume fraction, temperature rise, and electrolyte conductivity in the machining area at different times were obtained by combining them with the multi-physical fields simulation results. Subsequently, a series of ECTr experiments were conducted, in which, as the feed rate increased, the surface quality and machining accuracy of the inner blades were improved. Compared with the simulation results, the error in machining accuracy of the chamfer profile is controlled within +/- 2%, and the machining accuracy of the blade full profile was controlled within +/- 0.2 mm, indicating that the model proposed in this study was effective in predicting the evolution of inner blades ECTr with chamfer structures at blade tip. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Chamfer structure Inner blisk Electrochemical trepanning (ECTr) Dynamic evolution model Forming prediction Multiphysics Machining quality MATERIAL REMOVAL PROCESS CONVEX STRUCTURE SIMULATION MANUFACTURE PART

Numerical simulation of formaldehyde distribution characteristics in the high-speed train cabin

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Building Simulation 2024年第2期17卷 285-300页

作者： Fan Wu hang dong Chao Yu Hengkui Li Qingmin Cui Renze Xu Key Laboratory of Traffic Safety on Track Ministry of EducationSchool of Traffic&Transportation EngineeringCentral South UniversityChangshaHunan410075China Joint International Research Laboratory of Key Technologies for Rail Traffic Safety ChangshaHunan410075China National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle ChangshaHunan410075China School of Software Henan University of EngineeringZhengzhouHenan451191China

The global concern over indoor air pollution in public vehicles has grown *** a focus on enhancing passengers’comfort and health,this study endeavors to investigate the distribution characteristics of formaldehyde within a high-speed train cabin by employing a computational fluid dynamics(CFD)model which is experimentally validated in a real cabin *** research focuses on analyzing the impact of air supply modes,temperature,relative humidity,and fresh air change rate on the distribution and concentration of *** results demonstrate that the difference in average formaldehyde concentration between the two air supply modes is below 1.3%,but the top air supply mode leads to a higher accumulation of formaldehyde near the sidewalls,while the bottom air supply mode promotes a more uniform distribution of ***,the temperature,relative humidity,and fresh air change rate are the primary factors affecting formaldehyde concentration levels,but they have modest effects on formaldehyde’s distribution pattern within the *** the temperature and relative humidity increase,the changes in formaldehyde concentrations in response to variations in these factors become more ***,the formaldehyde concentration may surpass the standard limit of 0.10 mg/m^(3)if the fresh air change rate falls below 212 m^(3)/*** research provides a systematic approach and referenceable results for exploring formaldehyde pollution in high-speed train cabins.

关键词： indoor air pollution formaldehyde CFD simulation high-speed train ventilation

Helicobacter pylori mediated niche environment aberrations promote the progression of gastric cancer

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Genes & Diseases 2024年第5期11卷 113-116页

作者： Teng yan hang Sun Yuhui Liao Jiajian Zhou Nanfang Hospital The First School of Clinical MedicineSouthern Medical UniversityGuangzhouGuangdong 510515China Dermatology Hospital Southern Medical UniversityGuangzhouGuangdong 510091China

Intestinal metaplasia(IM)is a key stage in the tumorigenic Correa cascade from gastritis to final intestinal-type gastric cancer(GC).1 Helicobacter pylori(***)infection is the most common trigger of IM,and it promotes GC progression through induction of gastric epithelial transition.2 Currently,the mechanism by which *** infection promotes tumorigenesis in IM patients is poorly *** et *** a single-cell transcriptomic atlas on premalignant lesions and identified biomarkers of gastric early-malignant cells,providing an opportunity to explore the molecular mechanism of GC progression at the molecular level.

关键词： gastric pylori Helicobacter

Pannexins in the musculoskeletal system:new targets for development and disease progression

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Bone Research 2024年第2期12卷 255-269页

作者： yan Luo Shengyuan Zheng Wenfeng Xiao hang Zhang Yusheng Li Department of Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China Department of Clinical Medicine Xiangya Medicine SchoolCentral South UniversityChangshaHunan 410008China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

During cell differentiation,growth,and development,cells can respond to extracellular stimuli through communication ***(Panx)family and connexin(Cx)family are two important types of channel-forming *** family contains three members(Panx1-3)and is expressed widely in bone,cartilage and *** there is no sequence homology between Panx family and Cx family,they exhibit similar configurations and *** to Cxs,the key roles of Panxs in the maintenance of physiological functions of the musculoskeletal system and disease progression were gradually revealed ***,we seek to elucidate the structure of Panxs and their roles in regulating processes such as osteogenesis,chondrogenesis,and muscle *** also focus on the comparison between Cx and *** a new key target,Panxs expression imbalance and dysfunction in muscle and the therapeutic potentials of Panxs in joint diseases are also discussed.

关键词： skeletal diseases system