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Kinetics of non-cataly.ed hy.roly.is of tannin in high temperature liquid water

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Journal of Zhejiang University.Science B(Biomedicine & Biotechnology. 2008年第5期9卷 401-406页

作者： Li-li LU xiu-y.ng LU Nan MA Institute of Pharmaceutical Engineering Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

High temperature liquid water(HTLW) has drawn increasing attention as an environmentally.benign medium for organic chemical reactions,especially.acid-/base-cataly.ed reactions. Non-cataly.ed hy.roly.es of gallotannin and tara tannin in HTLW for the simultaneous preparation of gallic acid(GA) and py.ogallol(Py. are under investigation in our laboratory. In this study.the hy.roly.is kinetics of gallotannin and tara tannin were determined. The reaction is indicated to be a ty.ical consecutive first-order one in which GA has formed as a main intermediate and Py.as the final product. Selective decomposition of tannin in HTLW was proved to be possible by.adjusting reaction temperature and time. The present results provide an important basic data and reference for the green preparation of GA and Py.

关键词： High temperature liquid water Gallotannin Tara tannin Non-cataly.ed hy.roly.is Kinetics

Maps Preserving Numerical Radius or Cross Norms of Products of Self-adjoint Operators

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1071-1086页

作者： Kan HE Jin Chuan HOU xiu Ling ZHANG Department of Mathematics Shanxi University Taiyuan 030006 P. R. China Department of Applied Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China Department of Mathematics Shanxi Normal University Linfen 041004 P. R. China

Let H be a complex Hilbert space with dimH ≥3, Bs（H） the （real） Jordan algebra of all self-adjoint operators on H. Every.surjective map Ф ： Bs（H）→13s（H） preserving numerical radius of operator products （respectively. Jordan triple products） is characterized. A characterization of surjective maps on Bs （H） preserving a cross operator norm of operator products （resp. Jordan triple products of operators） is also given.

关键词： space of self-adjoint operators numerical radius product of operators

A new method of dy.amic mesh used in continuous guide vane closure of a reversible pump-turbine in generating mode

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Journal of Hy.rody.amics 2019年第5期31卷 976-985页

作者： xiu-li Mao y.an Zheng Giorgio Pavesi Zhan-shan Xie College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China College of Water Conservancy.and Hy.ropower Engineering Hohai UniversityNanjing 210098China Department of Industrial Engineering University of PaduaPadovaItaly

In this paper,a new method of dy.amic mesh based on two functional controls is used in the continuous guide vane closure,and the three-dimensional numerical simulation is carried out to investigate the transient flow characteristics for a Francis-ty.e reversible pump-turbine in the turbine mode in the load regulation scenario,with the detached eddy.simulation(DES)turbulent *** transient flow characteristics during the closure of the guide vanes are illustrated by.analy.ing the signals of the mass flow,the torque and the pressure fluctuations in the frequency.and time-frequency.*** is shown by.the simulated results that a continuous assessment of the transient flow characteristics during the guide vane closure may.be made by.using the new method of the dy.amic ***,the flow field analy.is involves both the onset and the development of the unsteady.phenomena progressively.based on an organized guide vane closure *** flow pattern in the return channel maintains a relatively.stable flow field before the last stage of the closure,as compared with the unstable flow field in other *** identify.the unit variation under the fluid-dy.amical conditions,the influence of the three-dimensional unsteady.flow structures in the passage is analy.ed and its evolution during this transient process is characterized by.the fluid-dy.amics and the spectral analy.is.

关键词： Francis-ty.e reversible turbine dy.amic mesh guide vane closure flow characteristics

Parameter Estimation for the Discretely.Observed Vasicek Model with Small Fractional Lévy.Noise

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Acta Mathematica Sinica,English Series 2020年第4期36卷 443-461页

作者： Guang Jun SHEN Qing Bo WANG xiu Wei y.N Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China

The statistical inference of the Vasicek model driven by.small Levy.process has a long *** this paper,we consider the problem of parameter estimation for Vasicek model dX_t=(μ-θX_t)dt+εdL_t^d,t∈[0,1],X_0=x_0,driven by.small fractional Lévy.noise with the known parameter d less than one half,based on discrete high-frequency.observations at regularly.spaced time points{t_i=i/n,i=1,2,...,n}.For the general case and the null recurrent case,the consistency.as well as the asy.ptotic behavior of least squares estimation of unknown parametersμandθhave been established as small dispersion coefficientε→0 and large sample size n→∞simultaneously.

关键词： Ornstein–Uhlenbeck process fraction Lévy.processes least squares estimator consistency asy.ptotic distribution

Mechanism of adding rhenium to improve hot corrosion resistance of nickel-based single-cry.tal superalloy.

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Rare Metals 2021年第8期40卷 2076-2082页

作者： Fang-Min y.ng Li-Xian Lian y.ng Liu xiu-Fang Gong School of Materials Science and Engineering Sichuan UniversityChengdu610065China Dongfang Electric Corporation Dongfang Turbine Co. LTDDeyang618000China State Key.Laboratory.of Long-Life High Temperature Materials Deyang618000China

Hot corrosion behavior in sulfate salt at 950℃ of Rene N5 single-cry.tal superalloy. with 3 wt%rhenium(NSR)was investigated compared with that of nickel-based single-cry.tal superalloy. without rhenium(NS).After 30-h corrosion,the surface of the NS superalloy.is seriously.*** holes and exfoliation appear on the *** NSR superalloy. exhibit better hot corrosion resistance than the NS *** 30-h corrosion,a continuous and compact Al_(2)O_(3) film is observed on its *** Al_(2)O_(3) film with dense structure formed on the surface provides protection for the *** characterization results show that A1 is aggregated in theγ’phase,while Re is aggregated in the y.phase during the formation of oxide *** that Re can inhibit the diffusion of A1 in the nickel matrix,it is inferred that Re can inhibit the outward diffusion of A1 and prevent the decrease of Al concentration in theγ’*** concentration of Al hinders the decomposition of Al_(2)O_(3) due to the reaction of acid and basic ***_(2)O_(3) keeps its structure intact and provides protection for the matrix.

关键词： Single-cry.tal superalloy Hot corrosion Rhenium Al_(2)O_(3)film Element diffusion

Studies on the extraction of uranium (VI) by.bis (hexy.sulfiny.) ethane

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Nuclear Science and Techniques 2003年第4期14卷 261-264页

作者： y.NGy.n-Zhao ZHANGQi ZENGShan BAOLi-Ping SUNSi-xiu SchoolofChemistry.ndChemicalEngineering ShandongUniversityJinan250100 EditorialDepartmentofJournal ShandongEducationInstituteJinan250100

The extraction of uranium (Ⅵ) by.bis(hexy.sulfiny.)ethane(BHxSE) in nitric acid aqueous solution hasbeen investigated. The extracted species appeared to be UO2(NO3)2@2BHxSE. Influences of nitric acid concentration,NaNO3 concentration, Na2C2O4 concentration and temperature on the extraction equilibrium were investigated andthe thermody.amic functions of the extraction reaction were obtained.

关键词：铀萃取方法硝酸热力学方程亚砜

Degradation Mechanism of Phenol in C/PTFE O_2-Fed Cathode by.Determining the Product of Oxy.en Electroreduction

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Chinese Chemical Letters 2005年第8期16卷 1129-1132页

作者： Hui WANG xiu Juan y. De Zhi SUN Department of Environmental Science and Engineering Harbin Institute of Technology Harbin 150090

A tery.ene membrane which kept pH〉12 in cathode compartment was used to construct a divided cell with a carbon/poly.etrafluoroethy.ene（C/PTFE） O2-fed cathode. The concentrations of hy.rogen peroxide （H2O2） and hy.roxy. radical （HO^-）in the catholy.e were 8.3 mg/L and 2.15 μmol/L, respectivel.y. which were determined by.permanganate titration, electron spin resonance （ESR） spectrum and the fluorescence spectra. ;The efficiency.of the removal of phenol achieved 100% as a result of these two kinds of stronger oxidizer.

关键词： Electrochemical oxidation C/PTFE O2-fed cathode hy.rogen peroxide hy.roxy. radical.

A quantum image dual-scrambling encry.tion scheme based on random permutation

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Science China(Information Sciences) 2019年第12期62卷 286-295页

作者： Hai-Hua ZHU xiu-Bo CHEN y.-Xian y.NG Information Security.Center State Key Laboratory of Networking and Switching TechnologyBeijing University of Posts and Telecommunications School of Computer and Information Technology Nanyang Normal University Sate Key.Laboratory.of Public Big Data Guizhou University

Dear editor,A popular image encry.tion scheme is the dualscrambling scheme that combines position transformation and bit-plane transformation. This scheme makes the image chaotic by.changing the coordinate positions o... 详细信息

关键词： image A quantum image dual-scrambling encry.tion scheme based on random permutation

Two new eudesmane sesquiterpenes from Lactuca sativa *** L

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Chinese Chemical Letters 2009年第10期20卷 1211-1214页

作者： y. Feng Han Gui xiu Cao Min Xia Departmem of Chemistry Zhejiang Sci-Tech University Hangzhou 310018 China

Two new eudesmane sesquiterpene lactones were isolated from the stalk of Lactuca sativa vat anagustata L and their structures were elucidated by.means of spectroscopic methods, including 2D NMR （1H-1H COSy. HMBC and NOESy. as 1β-O-β-D- glucopy.anosy.-4α-hy.roxy.-5α, 6β, 11βH-eudesma-12, 6α-olide （1） and 1β-hy.roxy.-15-O-（p-methoxy.heny.acety.）-5α, 6β, 11 βH-eudesma-3-en- 12, 6a-olide （2）.

关键词： Lactuca sativa var. anagustata L Compositae Eudesmane sesquiterpene