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Sum-connectivity index of a graph

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Frontiers of Mathematics in China 2016年第1期11卷 47-54页

作者： Kinkar Ch. DAS Sumana DAS bo zhou Department of Mathematics Sungkyunkwan University Suwon 440-746 Korea School of Information and Communication Engineering Sungkyunkwan UniversitySuwon 440-746 Korea Department of Mathematics South China Normal University Guangzhou 510631 China

Let G be a simple connected graph, and let di be the degree of its i-th vertex. The sure,connectivity index of the graph G is defined as χ（G） =∑vivj∈E（G）（di＋dj）-1/*** discuss the effect onχ（G）of inserting... 详细信息

关键词： Graph Randid index sum-connectivity index minimum degree

A macro-mechanical constitutive model of shape memory alloys

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1382-1391页

作者： zhou bo LIU YanJu LENG JinSong ZOU GuangPing College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China Department of Aerospace Science and Mechanics Harbin Institute of TechnologyHarbin 150001China Center for Composite Materials and Structures Science Park of Harbin Institute of Technology(HIT)Harbin 150080China

It is of practical interest to establish a precise constitutive model which includes the equations describing the phase transformation behaviors and thermo-mechanical processes of shape memory alloy (SMA). The microscopic mechanism of super elasticity and shape memory effect of SMA is explained based on the concept of shape memory factor defined by the author of this paper. The conventional super elasticity and shape memory effect of SMA are further unified as shape memory effect. Shape memory factor is redefined in order to make clear its physical meaning. A new shape memory evolution equation is developed to predict the phase transformation behaviors of SMA based on the differential relationship between martensitic volume fraction and phase transformation free energy and the results of DSC test. It overcomes the limitations that the previous shape memory evolution equations or phase transformation equations fail to express the influences of the phase transformation peak temperatures on the phase transformation behaviors and the transformation from twinned martensite to detwinned martensite occurring in SMA. A new macro-mechanical constitutive equation is established to predict the thermo-mechanical processes realizing the shape memory effect of SMA from the expression of Gibbs free energy. It is expanded from one-dimension to three-dimension with assuming SMA as isotropic material. All material constants in the new constitutive equation can be determined from macroscopic experiments, which makes it more easily used in practical applications.

关键词： shape memory alloy shape memory factor shape memory evolution equation constitutive equation

Molecular simulation study of the adhesion work for water droplets on water monolayer at room temperature

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Chinese Physics B 2021年第10期30卷 476-480页

作者： Mengyang Qu bo zhou Chunlei Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China Zhangjiang Laboratory Interdisplinary Research CenterShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The wetting phenomenon of water droplets coexisting with the ordered water monolayer termed an unexpected phenomenon of“water that does not wet a water monolayer”at room temperature has been found on several solid *** the hydrogen bond saturation inside the monolayer can qualitatively describe this phenomenon,whether the Young-Dupre equation still holds under this unconventional wetting framework is still not *** this work,we have´calculated the contact angle values of the droplets as well as the work of adhesion between the droplets and the monolayer based on an extended phantom-wall *** results show that similar to the conventional solid-liquid interface,classical Young-Dupre equation is also applicable for the interface of liquid water and ordered water monolayer.

关键词： wetting work of adhesion contact angle water

Interaction of {11■2} twin variants in hexagonal close-packed titanium

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Journal of Materials Science & Technology 2019年第4期35卷 660-666页

作者： Xiaocui Li Jingwei Li bo zhou Mingchao Yu Manling Sui Institute of Microstructure and Property of Advanced Materials Beijing University of Technology

As multiple{11■2}twin variants are often formed during deformation in hexagonal close-packed(hcp)titanium,the twin-twin interaction structure has a profound influence on mechanical *** this paper,the twin-twin interaction structures of the{11■2}contraction twin in cold-rolled commercial purity titanium were studied by using electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM).Formation of the{11■2}twin variants was found to deviate the rank of Schmid factor,and the non-Schmid behavior was explained by the high-angle grain boundary nucleation *** the observed twin-twin pairs manifested a quilted-looking structure,which consists of the incoming twins being arrested by the obstacle ***,the quilted-looking{11■2}twin-twin boundary was revealed by TEM and high resolution TEM ***-twinning,lattice rotation and curved twin boundary were observed in the obstacle twin due to the twin-twin reaction with the impinging twin.A twin-twin interaction mechanism for the{11■2}twin variants was proposed in terms of the dislocation dissociation,which will enrich the understanding for the propagation of twins and twinning-induced hardening in hcp metals and alloys.

关键词： HCP titanium {11■2} twin-twin interaction EBSD analysis TEM observation

Magnetic circuit optimization and experimental study of new internally excited automatic balancing

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High Technology Letters 2021年第2期27卷 173-183页

作者： Li Zhaoju Chen Lifang zhou bo Yan Ziwen zhou Shuhua Key Laboralery of Engine Health Monitoring Control and Nelworking of Ministry of Educalion Beijing University of Chemical TechnologyBejjing 100029P.R.China Beijing Key L.aboratery of Health Monitoring and Self-Recovery for High-End Mechanical FEquipment Beijing University of Chemical TechnologyBeijing 100029P.R.China

Mass imbalance-induced vibration affects the rotating machinery very large,especially the highspeed ***-line balancing techniques have been widely developed for rejecting unbalance-induced vibration but do not eliminate unbalanced vibration in the working ***,multiple start-stops are required in off-line balancing ***,research on an efficient electromagnetically-driven auto-balancer is carried out in the present work,and an internal excitation actuator is designed in this *** electromagnetic characteristics of the two copper coil bobbins in the internal excitation actuator are compared and *** permanent magnets inside the actuator are simulated and analyzed with different sections of round,rectangular,and *** the results show that the elliptic type has the largest self-locking ***,the dynamic balance test is performed on a test bench equipped with a designed electromagnetic balancing actuator,and the unbalance vibration is reduced from 130.23 μm to 5.98 μm.

关键词： unbalanced vibration rotating machinery automatie balancing actuator electro-magnetic simulation

Constitutive model for epoxy shape memory polymer with regulable phase transition temperature

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International Journal of Smart and Nano Materials 2021年第1期12卷 72-87页

作者： Fei Zhao Xueyao Zheng Shichen zhou bo zhou Shifeng Xue Yi Zhang College of Pipeline and Civil Engineering China University of Petroleum(East China)QingdaoChina

The epoxy shape memory polymer(SMP)with adjustable phase transition temperature is a kind of high-performance shape mem-ory polymer,which can change its phase transition temperature and improve its mechanical properties through the process of photo *** epoxy SMP constitutive model combining phase transition and viscoelasticity is established by discretizing the epoxy SMP into several glass phase units and rubbery phase units in this *** model includes the viscoelastic constitutive equa-tions of glass phase units and rubber phase units,the parameter expression during shape memory process,and material parameter equation during photocuring *** the stress relaxation behavior of epoxy SMP at different temperatures and the change of material parameters during the photo-curing process are simu-lated numerically,and the simulation results perform consistency with the experimental *** model can not only relate shape memory effect and phase transformation in physics but also better characterize the viscoelastic properties of SMP and predict the shape memory response of SMP.

关键词： Epoxy shape memory polymer constitutive model regulable phase transition temperature photo curing

Gold-catalyzed intermolecular reaction of ynamides with 3-indolyl azides via an unexpected 1,2-alkyl migration

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Science Bulletin 2017年第17期62卷 1201-1206页

作者： bo zhou Ying-Qi Zhang Xin Liu Long-Wu Ye State Key Laboratory of Physical Chemistry of Solid Surfaces and The Key Laboratory for Chemical Biology of Fujian Province College of Chemistry and Chemical EngineeringXiamen University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A gold-catalyzed intermolecular reaction of ynamides with 3-indolyl azides via the presumable α-imino gold carbenes has been developed, providing an alternative and efficient way for the synthesis of valuable 3-amino-β-carbolines in generally good to excellent yields. Importantly, this new protocol involves an unexpected 1,2-alkyl migration pathway.

关键词： Gold Heterocycles Migration Cyclization Tandem reaction

An adaptive physics-informed deep learning method for pore pressure prediction using seismic data

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Petroleum Science 2024年第2期21卷 885-902页

作者： Xin Zhang Yun-Hu Lu Yan Jin Mian Chen bo zhou State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China College of Artificial Intelligence China University of Petroleum(Beijing)Beijing102249China PetroChina Tarim Oilfield Company KorlaXinjiang841000China

Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum *** deep learning technique has been receiving more interest due to the great potential to deal with pore pressure ***,most of the traditional deep learning models are less efficient to address generalization *** fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic ***,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss *** machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure *** CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and bowers methods is also proposed to build machine-learnable labels for solving the problem of few *** validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization *** adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data.

关键词： Pore pressure prediction Seismic data 1D convolution pyramid pooling Adaptive physics-informed loss function High generalization capability

DiastereoselectiveandEnantioselectiveSynthesisof(1S,2S)-2-Ethyl-1-aminocyclopropaneCarboxylicAcid

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Chinese Chemical Letters 2002年第10期13卷 939-941页

作者： Yi bo zhou Jun An MA Li Xin WANG Qi Lin zhou State Key Laboratoratory and Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071

Pd(0) Complex prepared from Pd(dba)(2) and chiral quinolinyl-oxazoline ligand can catalyze alkylation and cyclization reaction of 1, 4-dichlorobut-2-ene 1 with anion of N-(diphenylmethylene)amino acetonitrile 2 to provide (E)-2-ethenyl-1-N-(diphenylmethylene) amino cyclopropane carbonitrile 3 with 100% de and 20% cc. Reduction of (E)-3 by diimide followed by acidic hydrolysis afforded (1S, 2S)-2-ethyl-1-aminocyclopropanecarboxylic acid 9, a natural product coronamic acid.

关键词： Chiral Pd catalyst quinolinyl-oxazoline cyclopropanecarboxylic acid.