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Reduction in Activity/Gene Expression of Anthocyanin Degradation Enzymes in Lychee Pericarp is Responsible for the Color Protection of the Fruit by Heat and Acid Treatment

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Journal of Integrative Agriculture 2013年第9期12卷 1694-1702页

作者： fang fang ZHANG Zhao-qi ZHANG xue-lian WU Zhen-xian YIN Hui-fang PANG xue-qun State Key Laboratory for Conservation and Utilization of Subtropical Agrobioresources/South China Agricultural University College of Life Sciences South China Agricultural University College of Horticulture South China Agricultural University

Heat and acid treatments were reported to be a promising substitute for SO2 fumigation in color protection of postharvest lychee （Litchi chinensis） fruits, but the mechanism was not clear. In the present study, hot water （70℃） dipping followed by immersion in 2% HC1 （heat-acid） substantially protected the red color of the fruit during storage at 25℃ and inhibited anthocyanin degradation while hot water dipping alone （heat） led to rapidly browning and about 90% loss in anthocyanin content. The pH values in the pericarp of the heat-acid treated fruit dropped to 3.2, while the values maintained around 5.0 in the heat-treated and control fruit. No significantly different pH values were detected among the arils of heat-acid, heat treated and control fruit. Heat-acid treatment dramatically reduced the activities of anthocyanin degradation enzyme （ADE）, peroxidase （POD） and polyphenol oxidase in the pericarp. A marked reduction in LcPOD gene expression was also detected in heat-acid treated fruit, in contrast, induction was found in heat treated fruit. The pericarp of heat-acid treated fruit exhibited significantly lower respiration rate but faster water loss than that of the untreated or heat treated fruit. Taken together, heat treatment triggered quick browning and anthocyanin loss in lychee fruit, while heat-acid treatment protected the fruit color by a great reduction in the activities/gene expression of anthocyanin degradation enzymes and acidification of lychee pericarp.

关键词： lychee fruit anthocyanin degradation enzymes color retention heat and acid treatment peroxidase geneexpression

Sb nanoparticles encapsulated in N-doped carbon nanotubes as freestanding anodes for high-performance lithium and potassium ion batteries

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Rare Metals 2023年第2期42卷 449-458页

作者： Xiao-Ping Lin fang-fang xue Zhi-Gang Zhang Qiu-Hong Li Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen361005China

Sb-based materials with high specific capacity have targeted as an alternative anode material for alkali metal ion ***,Sb nanoparticles embedded in hollow porous N-doped carbon nanotubes(Sb@N-C nanotubes)are used as freestanding anode for Li-ion batteries(LIBs)and K-ion batteries(PIBs).The Sb@N-C nanotubes demonstrate exceptional reversible capacity of643 mAh·g^(-1)at 0.1 A·g^(-1)with long cycle stability,as well as outstanding rate performance(219.6 mAh·g^(-1)at10 A·g^(-1))in *** the anode material of PIBs,they reveal impressive capacity of 325.4 mAh·g^(-1)at 0.1 A·g^(-1).The superior electrochemical properties mainly originate from the novel *** be specific,the obtained 3D connected network allows for quick ion and electron migration,and prevents the aggregation of Sb *** hollow porous nanotubes can not only accommodate the volume expansion of Sb nanoparticles during cycling,but also facilitate the infiltration of the electrolyte and reduce the ion diffusion *** work provides a new insight for designing advanced Sb-based anodes for alkali metal ion batteries.

关键词： Alkali metal ion batteries Freestanding electrode Hollow porous nanotube Sb@N-C nanotubes

Hyperbolic Metric and Normal Family

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Acta Mathematica Sinica,English Series 2014年第4期30卷 681-688页

作者： Cai Yun fang xue Cheng PANG School of Mathematical Sciences Fudan University School of Mathematical Sciences Nanjing Normal University Department of Mathematics East China Normal University

In this paper, we study the normality of the family of meromorphic functions from the viewpoint of hyperbolic metric. Then, a new sufficient and necessary condition is obtained, which can determine a given family of m... 详细信息

关键词： Hyperbolic metric normal family holomorphic function meromorphic function

Optimal Quadrature Problem on n-Information for Hardy-Sobolev Classes

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2371-2378页

作者： xue Hua LI Gen Sun fang College of Science China Agricultural University Beijing 100083 P. R. China School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

For β 〉 0 and an integer r 〉 2, denote by H∞,β those 2π-periodic, real-valued functions f on R, which are analytic in Sβ = {z ∈ C： [ImzI 〈β} and satisfy the restriction If（r）（z）[ ≤ 1, z ∈ Sβ. The optimal quadrature formulae about information composed of the values of a function and its kth （k ： 1,..., r - 1） derivatives on free knots for the classes H∞,β are obtained, and the error estimates of the optimal quadrature formulae are exactly determined.

关键词： Hardy-Sobolev class analytic function optimal quadrature formula n-information

Construction,Expression and Purification of SUMO1-GST Fusion Protein

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Chemical Research in Chinese Universities 2011年第2期27卷 245-248页

作者： QIAO Xiao-fang fang xue-dong LIU Jun The Second Hospital of Jilin University Changchun 130041 P. R.China

Sumoylation is an important protein modification discovered recently. SUMO（small ubiquitin-related modifier） pathway regulates the protein stability and transcriptional activity with a 12-kDa small molecular protein, SUMO, ligated to the target protein. The purification of SUMO proteins is a key step to reveal their function. The purpose of this study was to construct the recombinant SUMO1 gene cloned to a pGEX-4T-1 vector to express and purify the SUMO1-GST fusion protein in Escherichia coli. First, the full length DNA sequence of SUMO1 gene was amplified by PCR and was ligated to pMD18-T vector. Then the SUMO1 gene was subcloned to pGEX-4T-1 prokaryotic expression vector between BamHI and XhoI sites, and transformed in Escherichia coli DH5α cells. The right colonies were identified by restrictive enzyme digestion and sequencing. The correct rebombinant plasmid of pGEX-4T-1-SUMO1 was transformed in Escherichia coli BL21 cells and then induced by IPTG（isopropyl- β-D-1- thiogalacto-pyranoside） to express the SUMO1-GST fusion protein. The highly purified SUMO1-GST（glutathione S-transferase） fusion protein was obtained by affinity chromatography. Finally, the properties of SUMO1-GST fusion protein were confirmed by Coomassie brilliant blue strain and Western blot analysis. The recombinant plasmid of pGEX-4T-1-SUMO1 was successfully constructed, and SUMO1-GST fusion proteins were successfully expressed.

关键词： Small ubiquitin-related modifier 1 (SUMO1) Gutathione S-transferase(GST) fusion protein Affinity chromatography

Existence and Uniqueness of Positive Solutions to Three Coupled Nonlinear Schrdinger Equations

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 1021-1032页

作者： Guo-bei fang Zhong-xue L School of Mathematics and Statistics Jiangsu Normal University

In this paper, we consider existence and uniqueness of positive solutions to three coupled nonlinear SchrSdinger equations which appear in nonlinear optics. We use the behaviors of minimizing sequences for a bound to obtain the existence of positive solutions for three coupled system. To prove the uniqueness of positive solutions, we use the radial symmetry of positive solutions to transform the system into an ordinary differential system, and then integrate the system. In particular, for N = 1, we prove the uniqueness of positive solutions when 0≤ β=μ1 = μ2 =μ3 or β 〉 max{l,μ2,μ3}.

关键词： coupled nonlinear SchrSdinger equations positive solution existence uniqueness.

Lifted System Framework for Learning Control with Different Trial Lengths

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International Journal of Automation and computing 2015年第3期12卷 273-280页

作者： xue-fang Li Jian-Xin Xu Department of Electrical and Computer Engineering National University of Singapore

This paper addresses an iterative learning control(ILC) design problem for discrete-time linear systems with randomly varying trial lengths. Due to the variation of the trial lengths, a stochastic matrix and an iteration-average operator are introduced to present a unified expression of ILC scheme. By using the framework of lifted system, the learning convergence condition of ILC in mathematical expectation is derived without using λ-norm. It is shown that the requirement on classic ILC that all trial lengths must be identical is mitigated and the identical initialization condition can be also removed. In the end, two illustrative examples are presented to demonstrate the performance and the effectiveness of the proposed ILC scheme for both time-invariant and time-varying linear systems.

关键词： Iterative learning control average operator randomly varying trial lengths identical initialization condition lifted sys-tem.

Global Existence of Small Solutions for Cubic Quasi-linear Klein-Gordon Systems in One Space Dimension

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Acta Mathematica Sinica,English Series 2006年第4期22卷 1085-1102页

作者： Dao Yuan fang Ru Ying xue Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

In this paper, we consider a system of two cubic quasi-linear Klein-Gordon equations with different masses for small, smooth, compactly supported Cauchy data in one space dimension. We show that such a system has global existence when the nonlinearities satisfy a convenient null condition. Our results extend the global existence proved by Sunagawa recently under the non-resonance assumption to that under the resonance assumption.

关键词： Cubic Quasi-linear Klein-Gordon systems One space dimension Global existence Asymptotic behavior

Effect of parameters on Si plasma emission in collinear double-pulse laser-induced breakdown spectroscopy

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Frontiers of physics 2015年第5期10卷 83-90页

作者： fang-fang Chen xue-Jiao Su Wei-Dong Zhou Key Laboratory of Optical Information Detection and Display Technology of Zhejiang Zhejiang Normal University Jinhua 321004 China

Collinear dual-pulse laser-induced breakdown spectroscopy was carried out on Si crystal by using a pair of nanosecond Nd：YAG laser sources emitting at 1064 nm. The spectral intensities and signal- to-noise ratios of selected Si atomic and ionic lines were used to evaluate the optical emission. The optical emission intensity was recorded while varying the interpulse delay time and energy ratio of the two pulsed lasers. The effects of the data acquisition delay time on the line intensity and signal-to-noise ratio have been investigated as well. Based on the results, the optimal interpulse delay time, energy ratio of the two pulsed lasers, and data acquisition delay time for achieving the maximum atomic and ionic line intensities were found for generation of Si plasma with the collinear dual-pulse laser approach. The dominant mechanism for the observed line intensity variation was also discussed. In addition, the plasma temperature and electron number density at different gate delay times and different interpulse delay times were derived. A significant influence of plasma shielding on the electron temperature and electron number density at shorter interpulse delay times was observed.

关键词： laser-induced breakdown spectroscopy collinear dual-pulse plasma emission intensity