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Use of HPHT Autoclave to Determine Corrosion Inhibition Effect of Poly(methyl methacrylate-co-N-vinyl-2-pyrrolidone) on Carbon Steels in 3.5% NaCl Solution Saturated with CO_2

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Chinese Journal of Polymer Science 2015年第2期33卷 339-348页

作者： Ambrish Singh 林元华 Chun-yang Zhu yuan-peng wu Eno E.Ebenso State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Department of Chemistry School of Civil Engineering LFTS Lovely Professional University School of Material Science and Engineering (Southwest Petroleum University) Department of Chemistry School of Mathematical & Physical Sciences North-West University(Mafikeng Campus)

The influence of poly（methylmethacrylate-co-N-vinyl-2-pyrrolidone）, P（MMA-co-VP）, on corrosion of carbon steels（J55, N80, P110 SS and C110 steels） in 3.5 wt% NaCl solution saturated with CO2 was evaluated using static high pressure and high temperature（HPHT） autoclave. The surface was further evaluated by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and contact angle measurements. Quantum chemical calculations have been used to evaluate the structural, electronic and reactivity parameters of the inhibitor on the steels surface. SEM, XRD and contact angle measurement studies reveal that the surface of metals are quite unaffected after use of inhibitor in 3.5% NaCl solution saturated with CO2.

关键词： Polymer NMR Autoclave SEM XRD

Self-healing,Stretchable,Temperature-Sensitive and Strain-Sensitive Hydrogel-based Flexible Sensors

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Chinese Journal of Polymer Science 2023年第3期41卷 334-344,I0005页

作者： Chun-Xia Zhao Min Guo Jie Mao Yun-Tao Li yuan-peng wu Hua Guo Dong Xiang Hui Li School of Materials Science and Engineering Southwest Petroleum UniversityChengdu 610500China The Center of Functional Materials for Working Fluids of Oil and Gas Field Sichuan Engineering Technology Research Center of Basalt Fiber Composites Development and ApplicationSouthwest Petroleum UniversityChengdu 610500China State Key Lab of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

Flexible hydrogels have shown promise as strain sensors in medical monitoring,human motion detection and intelligent *** a hydrogel strain sensor,certain challenges need to be urgently addressed for practical applications,such as the damage caused by external effects,leading to equipment failure,and the inability to perceive ambient temperature,resulting in single ***,a stretchable,self-healing and dual temperature-strain sensitive hydrogel,with a physically-crosslinked network,is designed by constructing multiple dynamic reversible *** oxide(GO)and iron ions(Fe^(3+))act as dynamic bridges in the cross-linked network and are mediated by the covalent and hydrogen bonding,rendering excellent stretchability to the *** reversible features of coordination interactions and hydrogen interactions endow excellent recoverability and self-healing ***,the incorporated N-isopropyl acrylamide(NIPAM)provides excellent temperature responsiveness to the hydrogel,facilitating the detection of external temperature ***,the hydrogels exhibited strain-sensitivity,with a wide working range of 1%-300%,fast response and electrical stability,which can be used as flexible sensors to monitor body motions,e.g.,speaking and the bending of finger,wrist,elbow and ***,the hydrogel possesses dual sensory capabilities,combining external temperature and strain,for potential applications in wearable multifunctional sensing devices.

关键词： Hydrogel sensor Self-healing Dual temperature-strain sensitive Monitor body motions

BDSec:Security Authentication Protocol for BeiDou-Ⅱ Civil Navigation Message

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China Communications 2024年第6期21卷 206-218页

作者： wu Zhijun Zhang yuan Yang Yiming Wang peng Yue Meng School of Safety Science and Engineering Civil Aviation University of ChinaTianjin 300300China School of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

Due to the lack of authentication mechanism in BeiDou navigation satellite system(BDS),BD-Ⅱ civil navigation message(BDⅡ-CNAV) are vulnerable to spoofing attack and replay *** solve this problem,we present a security authentication protocol,called as BDSec,which is designed by using China’s cryptography Shangyong Mima(SM) series algorithms,such as SM2/4/9 and Zu Chongzhi(ZUC)*** BDSec protocol,both of BDⅡ-CNAV and signature information are encrypted using the SM4 algorithm(Symmetric encryption mechanism).The encrypted result is used as the subject authentication *** protocol applies SM9 algorithm(Identity-based cryptography mechanism) to protect the integrity of the BDⅡ-CNAV,adopts the SM2 algorithm(Public key cryptosystem) to guarantee the confidentiality of the important session information,and uses the ZUC algorithm(Encryption and integrity algorithm) to verify the integrity of the message authentication serial number and initial information and the information in authentication initialization sub-protocol *** results of the SVO logic reasoning and performance analysis show that BDSec protocol meets security requirements for the dual user identity authentication in BDS and can realize the security authentication of BDⅡ-CNAV.

关键词： BDII civil navigation messages(BDIICNAV) BeiDou navigation satellite system(BDS) identity-based cryptography mechanism navigation message authentication protocol(BDSec)

MOF glass foam: a blueprint to porous membrane scaling-up

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Science China Chemistry 2024年第3期67卷 746-748页

作者： yuan peng Weishen Yang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

In comparison with conventional energy-intensive separation technologies, such as distillation and crystallization,membrane separation is labelled as an advanced technology with low energy consumption, a small carbon footprint,continuous operation, etc. Metal-organic frameworks(MOFs) are a burgeoning category of crystalline materials consisting of metal ions/clusters coordinated with organic ligands.

关键词： separation porous distillation

Elucidating and manipulating pressure-induced water intrusion–extrusion in tunable hydrophobic Co/Zn bimetallic ZIFs:Roles of pore size and hydrogen bond

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Nano Research 2024年第1期17卷 344-353页

作者： Diyi Fang Chuanlei Liu Yu Chen Qilong peng Kongguo wu Yuxiang Chen Hao Jiang yuan wu Benxian Shen Qiumin wu Di wu Hui Sun International Joint Research Center of Green Energy Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Alexandra Navrotsky Institute for Experimental Thermodynamics The Gene and Linda Voiland School of Chemical Engineering and BioengineeringMaterials Science and Engineeringand Department of ChemistryWashington State UniversityWashington 99163USA

Porous heterogeneous lyophobic systems(HLSs)find potential applications in energy restoring,dissipating,and ***,the development of controllable HLSs still lacks rational structure design of nanoporous materials matching the molecular sizes of adopted *** that,thoroughly understanding the underlying transportation mechanism in the confined nano channels is greatly *** this work,a series of Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs)with tunable structures were synthesized via regulating the Co to Zn ratios and employed to investigate the intrusion–extrusion of liquid water in confined *** characterizations confirm the heterometallic coordination in the Co/Zn-doped *** intrusion–extrusion experiments unlock the relationship between the intrusion pressure and the nanopore size and realize the evolution of the HLSs between molecular spring and *** addition,cycling tests indicate the reversible structure change of Co/Zn ZIFs encountering pressure-induced water *** combination with molecular dynamics simulations,we present that the water multimers intrude into nanopores of ZIFs in chain-like forms along with dissociation of hydrogen bonds(HBs).Water molecules in the pre-intrusion state exhibit reduced HBs in response to the increase of pressure and linear structure with 1.6–3.0 HBs on *** transition to the post-intrusion situation,the associative configuration of water tends to exhibit the tetrahedral ***,we highlight the roles of pore size and HB in synergically dominating the pressure-induced intrusion–extrusion of liquid water in hydrophobic ***,the present work can also guide the development of functional guest–host systems based on porous architectures.

关键词： heterometallic zeolitic imidazolate frameworks nanopore intrusion hydrogen bonds

Dynamics of iron and aluminum storages in a subtropical forest headwater stream

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Journal of Mountain Science 2024年第7期21卷 2193-2205页

作者： YI Qiumeng MA Diting peng Yan ZHAO Zemin yuan Chaoxiang yuan Ji NI Xiangyin wu Fuzhong YUE Kai AN Nannan Key Laboratory of Humid Subtropical Eco-geographical Processes of Ministry of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350117China Fujian Sanming Forest Ecosystem National Observation and Research Station Sanming 365002China

The forest headwater streams are important hubs for connecting terrestrial and aquatic ecosystems,with plant litter and sediments as the major carriers for material migrations;however,until now we knew little about the dynamics of trace elements such as iron(Fe)and aluminum(Al)in forest headwater ***,we quantitatively identified the spatiotemporal dynamics of Fe and Al storages in plant litter and sediments and their influencing factors in a subtropical forest headwater stream,and assessed the potential pollution *** results showed that:(1)the mean concentrations of Fe and Al in plant litter(sediments)were 5.48 and 8.46(7.39 and 47.47)g·kg^(-1),and the mean storages of Fe and Al in plant litter(sediments)were 0.26 and 0.43(749.04 and 5030.90)g·m^(-2),respectively;(2)the storages of Fe and Al in plant litter and sediments significantly fluctuated from January to December,and showed a decreasing pattern from the source to mouth;and(3)storages of Fe and Al had no significant correlation with riparian forest type and the present of tributary and the Fe and Al storages in plant litter were mainly affected by water temperature and water alkalinity,and their storages in sediments were mainly affected by water temperature and frequency of rainfall;and(4)there were no anthropogenic pollution in Fe and Al in the forest headwater *** study revealed the primary factors of concentrations and storages of Fe and Al in plant litter and sediments in a forest headwater stream,which will improve our understanding of the role of headwater streams in forest nutrient storage and cycling along with hydrological processes.

关键词： Plant litter Sediments Storage Forest headwater stream Stream characteristics Trace element

Resource Allocation to Minimize the Makespan with Multi-Resource Operations

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Journal of Systems Science & Complexity 2024年第5期37卷 2054-2070页

作者： WENG wuyan CHU Chengbin wu peng School of Economics and Management Fuzhou UniversityFuzhou 350108China Univ Gustave Eiffel ESIEE Paris&COSYS-GRETTIAF-77454 Marne-la-ValléeFrance

This paper investigates a new resource-allocation problem involving multi-resource operations,where completing an operation requires simultaneous use of multiple(renewable)resources,probably of different *** goal of the study is to provide a solution method that minimizes the *** authors formulate the problem into a novel mixed-integer linear program(MILP)*** efficiently solve practical-sized instances,an exact Benders decomposition algorithm is *** algorithm divides the original problem into a master problem of allocating resources and a subproblem of calculating the makespan,and both are linked via Benders *** convergence is sped up by improving the mathematical model and embedding the variable neighborhood search *** with CPLEX,a commonly used MILP solver,the computational results demonstrate that the proposed algorithm provides tighter upper and lower bounds in most *** particular,compared with CPLEX,the proposed method can on average improve the upper and lower bounds by 4.76%and 4.39%,respectively,in solving practical-sized instances.

关键词： Benders decomposition multi-resources operations resource allocation

L vector spaces and L fields

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Science China Mathematics 2024年第10期67卷 2195-2216页

作者： Yinhe peng Liuzhen wu Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

We construct in ZFC(the Zermelo-Fraenkel system with choice) an L topological vector space—a topological vector space that is an L space—and an L field—a topological field that is an L space. This generalizes earli... 详细信息

关键词： minimal walk topological vector space topological eld L space L vector space L eld

Development of component stiffness equations for thread-fixed one-side bolt connections to an enclosed rectangular hollow section column under tension

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-Wei wu yuan-Qi LI Department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation