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Nuclear Science and Techniques 2016年第3期27卷 68-73页

作者： Yu Cui Xiao-Feng Yang cheng Yang ye-Xin Li Guo-zhu Chen Guo-Xin Sun School of Chemistry and Chemical Engineering University of Jinan

The extraction of uranyl nitrate by novel extractants of N,N-dimethyl-N',N'-dioctylsuccinylamide(DMDOSA)and N,N-dimethyl-N',N'-didecylsuccinylamide(DMDDSA) from aqueous nitric/nitrate solutions was *** was found both the concentration of HNO_3 and extractants had an effect on the U(Ⅵ) extraction *** extraction mechanism was established,and stoichiometry of the main extracted species was confirmed to be UO_2(NO_3)_2·2DMDOSA and UO_2(NO_3)_2·2DMDDSA,*** of the extraction reactions are *** spectral study of the U(Ⅵ) extracted species was also made.

关键词：溶剂萃取二甲基环己烷 ftir光谱硝酸铀酰化学计量比 O3浓度萃取反应

Joint Analysis of Recurrent Event Data with a Dependent Terminal Event

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Journal of Systems Science & Complexity 2017年第6期30卷 1443-1458页

作者： ye Peng DAI Jiajia zhu Jun School of Statistics University of International Business and Economics School of Mathematics and Statistics Guizhou University Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences

Recurrent event data frequently occur in many longitudinal studies, and the observation on recurrent events could be stopped by a terminal event such as death. This paper considers joint modeling and analysis of recurrent event and terminal event data through a common subject-specific frailty, in which the proportional intensity model is used for modeling the recurrent event process and the additive hazards model is used for modeling the terminal event time. Estimating equation approaches are developed for parameter estimation and asymptotic properties of the resulting estimators are established. In addition, some procedures are presented for model checking. The finite sample behavior of the proposed estimators is evaluated through simulation studies, and an application to a heart failure study is provided.

关键词： Additive hazards model estimating equation frailty recurrent events terminal event

DIMENSIONS OF ATACTIC POLY(α-METHYLSTYRENE)CHAINS WITH SIDE GROUPS

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Chinese Journal of Polymer Science 2006年第1期24卷 87-93页

作者： Hai-zhu Ma Gao-xiang ye Department of Physics Zhejiang University Hangzhou 310027 China Department of Physics Zhejiang Education Institute Hangzhou 310012 China

An improved configurational-confomational statistical method is developed and the mean-square radius of gyration for atactic poly（α-methylstyrene）（PαMS） chains is studied, in which the effect of large side groups is considered. The deduced formulas, based on the rotational isomer state theory, are used to investigate the configuration-dependent properties of the atactic polymer chain, and the statistical correlation of the unperturbed polymer chain dimension and structure parameters are calculated. For the fraction of meso dyads Wm= 0.4, the dependence of the radius of gyration Rg and the intrinsic viscosity [η] on the molecule mass M are Rg = 2.63×10^-2 M^0.50 nm and [η] = 7.36 × 10^-2 M^0.497, respectively, which are in agreement with the previous experimental data for the PαMS samples. A small hump is detected in the curve of the characteristic ratio of the unperturbed mean-square radius of gyration versus the chain length for short PαMS chains. The Rg increases linearly with the temperature T, and the effects of the chain length and the tacticity on the temperature coefficient are remarkable. These are quite different from the results for PαMS chains not considering side groups or for the monosubstituted polystyrene chain.

关键词： Side groups Rotational isomeric state Radius of gyration Poly(α-methylstyrene) chain.

Unperturbed dimensions of atactic poly(dibenzyl itaconate)s

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 991-998页

作者： MA Hai-zhu ye Gao-xiang Department of Physics Zhejiang University Hangzhou 310027 China School of Science and Technology Zhejiang Education Institute Hangzhou 310012 China

The unperturbed dimension and temperature character of poly(dibenzyl itaconate)s (PDBzI) are studied by a revised rotational isomeric state (RIS) method. The improved formulas of the mean-square radius of gyration, deduced by the pseudo-stereochemical equilibrium approach, may be used to investigate the configurational-conformational properties of atactic polymers with large side groups [poly(itaconates) for instance]. The calculated results showed that poly(itaconates) have larger dimension of the molecule than other vinyl polymers. Comparison of the dimension between considering and without considering side groups showed that the effect of large side groups on the unperturbed dimension for short-chain polymers is more obvious than that of long-chain polymers and, if the dimension of side groups increases, the effect also increases. The dimension differences of PDBzI between short-chain and long-chain polymers are investigated by the relation of characteristic ratios and temperature coefficients with temperature. Moreover, the dependence between the temperature coefficients and the tacticity of chains shows that the temperature characters of the isotactic, syndiotactic and atactic PDBzI chains have remarkable difference.

关键词： Poly(dibenzyl itaconate)s Mean-square radius of gyration Temperature coefficient Tacticity

A modified Kelvin impact model for pounding simulation of base-isolated building with adjacent structures

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Earthquake Engineering and Engineering Vibration 2009年第3期8卷 433-446页

作者： ye Kun Li Li zhu Hongping College of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China

Base isolation can effectively reduce the seismic forces on a superstructure, particularly in lowto medium-rise buildings. However, under strong near-fault ground motions, pounding may occur at the isolation level between the baseisolated building （BIB） and its surrounding retaining walls. To effectively investigate the behavior of the BIB pounding with adjacent structures, after assessing some commonly used impact models, a modified Kelvin impact model is proposed in this paper. Relevant parameters in the modified Kelvin model are theoretically derived and numerically verified through a simple pounding case. At the same time, inelasticity of the isolated superstructure is introduced in order to accurately evaluate the potential damage to the superstructure caused by the pounding of the BIB with adjacent structures. The reliability of the modified Kelvin impact model is validated through numerical comparisons with other impact models. However, the difference between the numerical results from the various impact analytical models is not significant. Many numerical simulations of BIBs are conducted to investigate the influence of various design parameters and conditions on the peak inter-story drifts and floor accelerations during pounding. It is shown that pounding can substantially increase floor accelerations, especially at the ground floor where impacts occur. Higher modes of vibration are excited during poundings, increasing the inter-story drifts instead of keeping a nearly rigid-body motion of the superstructure. Furthermore, higher ductility demands can be imposed on lower floors of the superstructure. Moreover, impact stiffness seems to play a significant role in the acceleration response at the isolation level and the inter-story drifts of lower floors of the superstructure. Finally, the numerical results show that excessive flexibility of the isolation system used to minimize the floor accelerations may cause the BIB to be more susceptible to pounding under

关键词： structural pounding base-isolation near-fault ground motions Kelvin impact model nonlinear damping

Lithiophilic Cu-Li_(2)O matrix on a Cu Collector to Stabilize Lithium Deposition for Lithium Metal Batteries

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Energy & Environmental Materials 2022年第4期5卷 1270-1277页

作者： Zhe Gong cheng Lian Pengfei Wang Kai Huang Kai zhu Ke ye Jun Yan Guiling Wang Dianxue Cao Key Laboratory of Superlight Materials and Surface Technology of Ministry of Education College of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Lithium metal anode is the most ideal candidate for next-generation energy storage ***,the uncontrolled dendrite growth,infinite volume expansion,and undesired side reactions lead to serious safety issues and hinder their potential ***,a pre-lithiation strategy is proposed to construct a high-lithiophilic Cu-Li_(2)O matrix on commercial Cu *** in situ-generated Li_(2)O promises adequate nucleation sites and strengthens solid electrolyte interphase and lateral lithium ***,the existence of 3D matrix reduces the local current *** synergy effect of Li_(2)O and Cu suppresses the growth of lithium *** a result,Cu-Li_(2)O matrix reveals an enhanced lithium plating/stripping behavior with Coulombic efficiency of 98.46%after 270 *** symmetrical cell assembled by Li-plated electrodes displays a prolonged lifespan of 1400 *** work demonstrates a scalable and effective approach for modified current collectors toward stable Li metal anode.

关键词： Cu-Li_(2)O matrix current collectors Li metal anodes SEI film

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Acta Mechanica Sinica 2023年第1期39卷 1-3页

作者： Xiaoyan ye Hongyang cheng College of Civil Engineering and Mechanics Lanzhou UniversityLanzhou 730000China Department of Civil Engineering Faculty of Engineering TechnologyMESA+University of Twente7500 AE EnschedeThe Netherlands

Granular matter is the second most handled material after water in the global *** macroscopic behavior arises from a collisional to a collective motion of the constituent grains,with varying lengths and time *** fluid-like and solid-like behaviors of granular materials and their transitions[1]are relevant to many industrial problems,such as mining excavation[2],selective laser sintering and powder spreading[3],thawing-induced slope failure[4],and granular impact[1].Designing and optimizing these processes require a synergy of understandings obtained from studies of contact theories[5],particle morphology or shape representation[5,6],interparticle friction[7],and micro-tomacro[4,7,8]and discrete-to-continuum transitions[1,2].

关键词： friction transitions collective

Variation characteristics of atmospheric methane and carbon dioxide in summertime at a coastal site in the South China Sea

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Frontiers of Environmental Science & Engineering 2022年第11期16卷 165-175页

作者： Yangyan cheng ye Shan Yuhuan Xue Yujiao zhu Xinfeng Wang Likun Xue Yanguang Liu Fangli Qiao Min Zhang Key Laboratory of Marine Sciences and Numerical Modeling First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Environment Research Institute Shandong UniversityQingdao 266237China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Shandong Key Laboratory of Marine Sciences and Numerical Modeling Qingdao 266061China

Methane(CH_(4))and carbon dioxide(CO_(2))are the two most important greenhouse gases(GHGs).To examine the variation characteristics of CH_(4)and CO_(2)in the coastal South China Sea,atmospheric CH_(4)and CO_(2)measurements were performed in Bohe(BH),Guangdong,China,in summer *** using an adaptive data analysis method,the diurnal patterns of CH_(4)and CO_(2)were clearly extracted and analysed in relation to the sea breeze(SB)and land breeze(LB),*** average concentrations of CH_(4)and CO_(2)were 1876.91±31.13 ppb and 407.99±4.24 ppm during SB,and 1988.12±109.92 ppb and 421.54±14.89 ppm during LB,*** values of CH_(4)and CO_(2)during SB basically coincided with the values and trends of marine background sites,showing that the BH station could serve as an ideal site for background GHG monitoring and dynamic *** extracted diurnal variations in CH_(4)and CO_(2)showed sunrise high and sunset low patterns(with peaks at 5:00–7:00)during LB but mid-morning high and evening low patterns(with peaks at 9:00)during *** diurnal amplitude changes in both CH_(4)and CO_(2)during LB were almost two to three times those during *** direction significantly modulated the diurnal variations in CH_(4)and CO_(2).The results in this study provide a new way to examine the variations in GHGs on different timescales and can also help us gain a better understanding of GHG sources and distributions in the South China Sea.

关键词： Methane Carbon dioxide Diurnal pattern Ensemble empirical mode decomposition South China Sea Sea breeze

Synthesis and characteristic of double hydrophilic block copolymer with amine pendant chains

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Chinese Chemical Letters 2008年第3期19卷 355-358页

作者： Yue Jun zhu ye Bang Tan Xu Du Ji cheng Piao Qi Feng Zhou School of Chemistry and Chemical Engineering Shandong University Jinan 250100 China Key Laboratory of Colloid and Interface Chemistry Shandong University Ministry of Education Jinan 250100 China

Novel double hydrophilic block copolymers with amine pendant chains were synthesized by polymerization of 4-vinyl benzylamine hydrochloric salt using 4,4′-azo-bis[4-cyanopentanoate poly（ethylene glycol） ester] as macroazoinitiator. The structures of the copolymers were characterized by ^1H NMR, FTIR spectra and acid-base titration, GPC-MALS techniques.

关键词： Polyamine Macroazoinitiator Double hydrophilic block copolymer

Thermo-hydro-poro-mechanical responses of a reservoir-induced landslide tracked by high-resolution fiber optic sensing nerves

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1018-1032页

作者： Xiao ye Hong-Hu zhu Gang cheng Hua-Fu Pei Bin Shi Luca Schenato Alessandro Pasuto School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China School of Computer Science North China Institute of Science and Technology(National Safety Training Center of Coal Mines)Beijing101601China State Key Lab of Coastal and Offshore Engineering Department of Geotechnical EngineeringDalian University of TechnologyDalian116024China National Research Council-Research Institute for Geo-Hydrological Protection(CNR-IRPI) Padova35127Italy Department of Information Engineering University of PadovaPadova35131Italy

Thermo-poro-mechanical responses along sliding zone/surface have been extensively ***,it has not been recognized that the potential contribution of other crucial engineering geological interfaces beyond the slip surface to progressive ***,we aim to investigate the subsurface multiphysics of reservoir landslides under two extreme hydrologic conditions(*** and dry),particularly within sliding *** on ultra-weak fiber Bragg grating(UWFBG)technology,we employ specialpurpose fiber optic sensing cables that can be implanted into boreholes as“nerves of the Earth”to collect data on soil temperature,water content,pore water pressure,and *** Xinpu landslide in the middle reach of the Three Gorges Reservoir Area in China was selected as a case study to establish a paradigm for in situ thermo-hydro-poro-mechanical *** UWFBG-based sensing cables were vertically buried in a 31 m-deep borehole at the foot of the landslide,with a resolution of 1 m except for the pressure *** reported field measurements covering the period 2021 and 2022 and produced the spatiotemporal profiles throughout the *** show that wet years are more likely to motivate landslide motions than dry *** annual thermally active layer of the landslide has a critical depth of roughly 9 m and might move downward in warmer *** dynamic groundwater table is located at depths of 9e15 m,where the peaked strain undergoes a periodical response of leap and withdrawal to annual hydrometeorological *** interface behaviors may support the interpretation of the contribution of reservoir regulation to slope stability,allowing us to correlate them to local damage events and potential global *** paper also offers a natural framework for interpreting thermo-hydro-poro-mechanical signatures from creeping reservoir bank slopes,which may form the basis for a landslide monitoring and early warning system.

关键词： Reservoir landslide Thermo-hydro-poro-mechanical response Ultra-weak fiber bragg grating(UWFBG) subsurface evolution Engineering geological interface Geotechnical monitoring