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Pt nanodendrites with a PtIr alloy surface structure exhibit excellent stability toward acidic hydrogen evolution reaction

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Nano Research 2024年第6期17卷 4844-4849页

作者： Chang Liu Zongnan wei Minna cao Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

The development of effective and stable electrocatalysts for the hydrogen evolution reaction(HER)in acidic electrolytes is a significant *** this work,homogeneous Pt nanodendrites(Pt Nds)with a PtIr shell were successfully synthesized by a two-step wet chemical *** open three-dimensional(3d)dendritic structure exhibited exceptional electrocatalytic characteristics,exposing as many active sites as ***,by alloying Ir with Pt on the surface,catalytic activity was greatly enhanced while ensuring extremely high *** surface-enriched platinum nanodendritic catalysts(Pt@PtIr Nds)outperformed the control samples and the commercial *** acidic HER test,Pt@PtIr Nds had a lower overpotential(22 mV)than Pt Nds(26 mV)and commercial Pt/C(31 mV)at 10 mA/cm^(2),and the activity of Pt@PtIr Nds remained consistent even after undergoing a continuous durability test for at least 168 h,which was much superior to the performance of commercial Pt/C(10 h)under identical test *** study revealed that the application of 3d Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER.

关键词： Pt nanodendrites iridium high stability hydrogen evolution reaction alloy

Preparation and characterization of pH-responsive metal-polyphenol structure coated nanoparticles

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Food Science and Human wellness 2024年第3期13卷 1303-1310页

作者： Qile Xia Yan Liang Ailing cao Yan cao Luyun Cai Key Laboratory of Post-Harvest Handling of Fruits Food Science InstituteZhejiang Academy of Agricultural SciencesHangzhou 310021China Ningbo Research Institute College of Biosystems Engineering and Food ScienceZhejiang UniversityNingbo 315100China School of Biological and Chemical Engineering Zhejiang Engineering Research Center for Intelligent Marine Ranch EquipmentNingboTech UniversityNingbo 315100China College of Food Science and Engineering Bohai UniversityJinzhou 121013China Hangzhou Customs district Hangzhou 310007China

In this paper,tannic acid(TA)and Fe~(3+)were added to form a layer of metal-polyphenol network structure on the surface of the nanoparticles which were fabricated by zein and carbon quantum dots(CQds)encapsulating phlorotannins(PTN).pH-Responsive nanoparticles were prepared successfully(zein-PTN-CQds-Fe-~Ⅲ).Further,the formation of composite nanoparticles was confirmed by a series of characterization *** zeta-potential and Fourier transform infrared spectroscopy data proved that electrostatic interaction and hydrogen bonding are dominant forces to form *** encapsulation efficiency(EE)revealed that metal-polyphenol network structure could improve the EE of *** analysis and differential scanning calorimetry experiment indicated the thermal stability of zein-PTN-CQds-Fe~Ⅲnanoparticles increased because of metal-polyphenol network *** pH-responsive nanoparticles greatly increased the release rate of active substances and achieved targeted release.

关键词： Metal Phlorotannins Nanoparticles pH-Responsive Characterization

Reinforcing effects of polypropylene on energy absorption and fracturing of cement-based tailings backfill under impact loading

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 650-664页

作者： Jiajian Li Shuai cao Erol Yilmaz School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines of Ministry of Education University of Science and Technology BeijingBeijing 100083China department of Civil Engineering Geotechnical DivisionRecep Tayyip Erdogan UniversityFenerRize TR53100Turkey

Polypropylene(PP)fiber-reinforced cement-based tailings backfill(FRCTB)is a green compound material with superior crack resistance and has good prospects for application in underground ***,FRCTB exhibits susceptibility to dynamic events,such as impact ground pressure and blast *** paper investigates the energy and crack distribution behavior of FRCTB under dynamic impact,considering the height/diameter(H/d)*** Hopkinson pressure bar,industrial computed tomography scan,and scanning electron microscopy(SEM)experiments were carried out on six types of *** outcomes confirmed fiber aggregation at the bottom of *** H/d was less than 0.8,the proportion of PP fibers distributed along theθangle direction of80°-90°*** the total energy,all samples presented similar energy absorption,reflectance,and ***,a rise in H/d may cause a rise in the energy absorption rate of FRCTB during the peak phase.A positive correlation existed between the average strain rate and absorbed energy per unit *** increase in H/d resulted in a decreased crack volume fraction of *** the H/d was greater than or equal to 0.7,the maximum crack volume fraction of FRCTB was observed close to the incidence *** cracks were present only in the FRCTB with an H/d ratio of *** with H/d ratios of 0.5 and 0.6 showed similar distributions of weakly and heavily damaged *** fibers can limit the emergence and expansion of cracks by influencing their *** observations revealed considerable differences in the bonding strengths between fibers and the *** that adhered particularly well to the substrate were attracted together with the hydration products adhering to *** results show that FRCTB is promising as a sustainable and green backfill for determining the design properties of mining with backfill.

关键词： cement-based tailings fiber-reinforced backfills fracture energy absorption impact loading

Adsorption limitation investigation on olefins for Cu–BTC

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Friction 2024年第4期12卷 606-617页

作者： Xiao YANG Yunbo wANG weihua cao Ruizheng JIANG Guoxin XIE Yuying cao Xiaowen QI School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Key Laboratory of Self-Lubricating Spherical Plain Bearing Technology of Hebei Province Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Aviation Key Laboratory of Science and Technology on Generic Technology of Self-Lubricating Spherical Plain Bearing Yanshan UniversityQinhuangdao 066004China

To utilize Cu-benzene-1,3,5-tricarboxylate(Cu-BTC)adsorbed lubricant oils in the self-lubricating field,the adsorption properties of Cu-BTC on different 1-olefins must be *** this work,1-hexene,1-octene,1-nonene,1-decene,1-undecene,and 1-dodecene were studied by the Monte Carlo method and *** adsorption limit of Cu-BTC for n-olefins was determined as 1-undecene by the adsorption *** suggested a limit for even straight-chain molecules to the adsorption of *** maximum ratio of the olefin length of the largest pore diameter(L/d)of Cu-BTC was approximately ***,theoretical calculations(radial distribution function(RdF))and experiments(infrared(IR)spectra)confirmed the interaction of n-olefin adsorbates and the Cu-BTC framework occurred between the-CH=of olefins and the Cu and O atoms of the Cu-BTC *** work adds to the understanding and investigation of the adsorption of liquid lubricants using Cu-BTC as a metal-organic framework(MOF).

关键词： metal-organic framework(MOF) Cu-benzene-1,3,5-tricarboxylate(Cu-BTC) Monte Carlo method adsorption properties 1-olefins

distributed Heterogeneous Multi-Agent Optimization with Stochastic Sub-Gradient

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Journal of Systems Science & Complexity 2024年第4期37卷 1470-1487页

作者： HU Haokun MO Lipo cao Xianbing School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China Research Centre for Agri-Product Quality Traceability Beijing Technology and Business UniversityBeijing 100048China School of Computer and Artificial Intelligence Beijing Technology and Business UniversityBeijing 100048China China Food Flavor and Nutrition Health Innovation Center Beijing Technology and Business UniversityBeijing 100048China

This paper studies the optimization problem of heterogeneous networks under a timevarying *** agent only accesses to one local objective function,which is *** improved algorithm with noisy measurement of local objective functions' sub-gradients and additive noises among information exchanging between each pair of agents is designed to minimize the sum of objective functions of all *** weaken the effect of these noises,two step sizes are introduced in the control *** graph theory,stochastic analysis and martingale convergence theory,it is proved that if the sub-gradients are uniformly bounded,the sequence of digraphs is balanced and the union graph of all digraphs is joint strongly connected,then the designed control protocol can force all agents to find the global optimal point almost *** last,the authors give some numerical examples to verify the effectiveness of the stochastic sub-gradient algorithms.

关键词： Communication noises distributed stochastic optimization heterogeneous networks subgradient measurement noises

Fatigue-resistant Hydrogels

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Chemical Research in Chinese Universities 2024年第1期40卷 64-77页

作者： LI Luofei LEI Hai cao Yi Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructureDepartment of PhysicsNanjing UniversityNanjing 210093P.R.China department of Physics Zhejiang UniversityHangzhou 310027P.R.China

Hydrogels have been extensively studied for applications in various fields, such as tissue engineering and soft robotics, as determined by their mechanical properties. The mechanical design of hydrogels typically focuses on the modulus, toughness, and deformability. These characteristics play important roles and make great achievements for hydrogel use. In recent years, a growing body of research has concentrated on the fatigue property of hydrogels, which determines their resistance to crack propagation in the networks during cyclic mechanical loads for applications. However, knowledge of hydrogel fatigue behavior remains notably deficient. Here, we present a brief overview of the fatigue behavior of hydrogels, encompassing the general experimental methods to measure the fatigue property and fundamental theoretical calculation models. Then, we highlight multiple strategies to enhance the fatigue resistance of hydrogels. Finally, we present our perspectives on fatigue-resistant hydrogels, outstanding challenges and potential directions for future research.

关键词： Hydrogel Fatigue-resistant Fracture

Formal Verification of data Modifications in Cloud Block Storage Based on Separation Logic

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Chinese Journal of Electronics 2024年第1期33卷 112-127页

作者： Bowen ZHANG Zhao JIN Hanpin wANG Yongzhi cao Key Laboratory of High Confidence Software Technologies (MOE) School of Computer Science Peking University School of Computer and Artificial Intelligence Zhengzhou University School of Computer Science and Cyber Engineering Guangzhou University

Cloud storage is now widely used, but its reliability has always been a major concern. Cloud block storage(CBS) is a famous type of cloud storage. It has the closest architecture to the underlying storage and can provide interfaces for other types. data modifications in CBS have potential risks such as null reference or data *** verification of these operations can improve the reliability of CBS to some extent. Although separation logic is a mainstream approach to verifying program correctness, the complex architecture of CBS creates some challenges for verifications. This paper develops a proof system based on separation logic for verifying the CBS data modifications. The proof system can represent the CBS architecture, describe the properties of the CBS system state, and specify the behavior of CBS data modifications. Using the interactive verification approach from Coq, the proof system is implemented as a verification tool. with this tool, the paper builds machine-checked proofs for the functional correctness of CBS data modifications. This work can thus analyze the reliability of cloud storage from a formal perspective.

关键词： Cloud computing Behavioral sciences Reliability Formal verification

The Investigation of data Voting Algorithm for Train Air-Braking System Based on Multi-Classification SVM and ANFIS

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Chinese Journal of Electronics 2024年第1期33卷 274-281页

作者： Juhan wANG Ying GAO Yuan cao Tao TANG School of Electronics and Information Engineering Beijing Jiaotong University Graduate department China Academy of Railway Science National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University

The pressure data of the train air braking system is of great significance to accurately evaluate its operation state. In order to overcome the influence of sensor fault on the pressure data of train air braking system, it is necessary to design a set of sensor fault-tolerant voting mechanism to ensure that in the case of a pressure sensor fault, the system can accurately identify and locate the position of the faulty sensor, and estimate the fault data according to other normal data. A fault-tolerant mechanism based on multi-classification support vector machine(SVM) and adaptive network-based fuzzy inference system(ANFIS) is introduced. Multi-classification SVM is used to identify and locate the system fault state, and ANFIS is used to estimate the real data of the fault sensor. After estimation, the system will compare the real data of the fault sensor with the ANFIS estimated data. If it is similar,the system will recognize that there is a false alarm and record it. Then the paper tests the whole mechanism based on the real data. The test shows that the system can identify the fault samples and reduce the occurrence of false alarms.

关键词： Support vector machines Fault diagnosis Pressure sensors Fuzzy logic Fault tolerance Adaptive systems Fault tolerant systems

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery