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国际医学放射学杂志 2024年第3期 374-374页

作者： X.Lin W.Guo d.She Y.Kang Z.Xing d.cao 孔令红

摘要目的探讨继发于自发性颈颅动脉夹层（sCCAd）的缺血性脑卒中相关因素，并评估与结局相关的初始影像学标志物。方法回顾性分析连续性sCCAd病人的初始和随访

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背景速度和波阻抗的同步反演

油气地球物理 2013年第3期11卷 69-72页

作者： d.cao 苏琴胜利油田分公司物探研究院山东东营257022

地震反射数据的全波形反演是非线性的,其原因是因为观测数据与合成地震数据之间的不对称性函数的形态是不规则的。非线性主要来源于描述地震速度的参数,完全非线性反演有另一种可选择的反演方法,就是相对于速度仍然是非线性的,但相对于... 详细信息

地震反射数据的全波形反演是非线性的,其原因是因为观测数据与合成地震数据之间的不对称性函数的形态是不规则的。非线性主要来源于描述地震速度的参数,完全非线性反演有另一种可选择的反演方法,就是相对于速度仍然是非线性的,但相对于波阻抗比却是线性的。消除非线性和线性部分之间的相互影响的传统方法是根据旅行时计算背景速度,根据波形计算波阻抗比。另一个更好的方法是通过利用单一最小二乘方范数波形失配标准同时得到地下的背景速度和波阻抗比。用一个稀疏网格将完全代表介质总特征的背景速度参数化,而用一个密集网格对波阻抗比进行参数化。对于每一个更新的速度模型来讲,波阻抗比是通过一个线性反演算法计算出来的。对于1d速度背景,用WKBJ和波恩近似法在f-k域进行反演非常有效。该方法均可对合成数据和野外数据进行很好地反演。

关键词：背景速度波阻抗反演模型函数

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

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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

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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

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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

Precipitation transformation pathway and mechanical behavior of nanoprecipitation strengthened Fe-Mn-Al-C-Ni austenitic low-density steel

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Journal of Materials Science & Technology 2024年第7期174卷 157-167页

作者： Y.F.An X.P.Chen L.Mei P.Ren d.Wei W.Q.cao College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Guangxi Engineering Research Center for Characteristic Metallic Powder Materials School of Electronic EngineeringGuangxi University of Science and TechnologyLiuzhou 545006China Central Iron&Steel Research Institute Beijing 100081China

Precipitation strengthening has been widely adopted in austenitic low-density steel owing to excellent hardened *** approach generally employs the coherentκ′carbides and non-coherent B2 *** the precipitation transformation pathway is decisive for further optimizing the microstructures under specific engineering ***,the detailed precipitation sequence of Fe-28Mn-11Al-1C-5Ni(wt%)austenitic low-density steel as well as its influence on mechanical prop-erties during aging process is systematically *** results reveal that nano-sizedκ′carbides domains(2 nm)exist in the solution-treated *** aging at 500℃for 1 h,the cuboidalκ′carbides(15-20 nm)uniformly disperse in austenite ***,after aging at 700℃for 15 min,the coarsenκ′carbides(30-35 nm)inhomogeneously distribute and align preferentially along the〈100〉***,extending the aging time to 60 min,the needle-type B2 particles replace theκ′carbides due to the enrichment of Ni elements at the phase boundaries among the austenite andκ′*** aging at 900℃,κ′carbides entirely dissolve into the austenite matrix,and the intragranular B2 particles are the sole precipitates in the austenite matrix and follow the K-S orientation relationship with *** work hardening capability seriously deteriorates due to the shearing ofκ′carbides by gliding *** the intragranular B2 particles preserve excellent work hardening rate by dislocations bow-out *** present work is meaningful for guiding the design of new generation dual-nano precipitation austenitic lightweight steel.

关键词： Lightweight steel κ′-carbides B2 particles Work hardening capability

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