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Numerical simulation of swirling flow effect on the first stage vane film cooling distribution

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第3期7卷 319-337页

作者： hong yin Electric Power Research Institute of Guangdong Power Grid Corporation Guangzhou Guangdong ProvinceP.R.China

In advanced gas turbine technology,lean premixed combustion is an effective strategy to reduce peak temperature and thus,NOX *** swirler is adopted to establish recirculation flow zone,enhancing mixing and stabilizing the ***,the swirling flow is dominant in the combustor flow field and has impact on the *** paper mainly investigates the swirling flow effect on the turbine first stage vane cooling system by conducting a group of numerical ***,the numerical methods of turbulence modeling using RANS and LES are *** computational model of one single swirl flow field is *** the RANS and LES results give reasonable recirculation zone *** comparing the velocity distribution,the RANS results generally match the experimental data but fail to at some local *** LES modeling gives better results and more detailed unsteady flow *** the second step,the RANS modeling is incorporated to investigate the vane film cooling performance under the swirling inflow boundary *** to the numerical results,the leading edge film cooling is largely altered by the swirling flow,especially for the swirl core-leading edge aligned *** to the pressure side,the suction side film cooling is more sensitive to the swirling ***,the film cooling jet is lifted and turned by the strong swirling flow.

关键词： Gas turbine swirling flow combustor simulator film cooling

Synthesis of Terpyridine Derivatives Containing β-Cyclodextrin

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Chinese Chemical Letters 2003年第5期14卷 445-447页

作者： Xian hong yin Department of Chemistry Guangxi University for NationalitiesNanning 530006

A novel b-cyclodextrin-based terpyridine derivatives has been prepared by the coupling of 4-(4-bromomethyl phenyl)- 2, 2:6, 2-terpyridine with mono-6-hydroxy permethylated b- cyclodextrin. The cyclodextrin dimmer appending a 4-phenyl-2,2:6,2- terpyridine spacer on the primary faces was synthesized by reaction of 4-phenyl-2,2:6,2-terpyridine-6,6-dicarbonitrile with an excess of 6-deoxy-6-O-tosyl-b-cyclodextrin.

关键词： Cyclodextrin terpyridine synthesis.

Characteristics of extreme temperature and precipitation in China in 2017 based on ETCCDI indices

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Advances in Climate Change Research 2018年第4期9卷 218-226页

作者： yin hong SUN ying Laboratory for Climate Studies National Climate Center China Meteorological Administration Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Nanjing 210044 China

Based on the homogenized daily data in 2419 stations in China from 1961 to 2017, we calculated 26 extreme temperature and precipitation indices as defined by the Expert Team on Climate Change Detection and Indices (ETCCDI), and analyzed the characteristics of extreme temperature and precipitation in China in 2017. For China average, all the high temperature indices were above the 30-year average of 1961e1990 and the extreme low temperature indices are lower than their corresponding 1961e1990 average. The most extreme precipitations in 2017 were within the range of one standard deviation of precipitation change during 1961e2017. The annual minima of daily maximum temperature (TXn) and daily minimum temperature (TNn) reached the recorded highest level, while the number of cold nights (TN10p), cold days (TX10p), and cold spell duration index (CSDI) reached the recorded lowest values. Some indices were ranked at the second or third place since 1961, including annual maxima of daily maximum temperature (TXx) and of daily minimum temperature (TNx), warm nights (TN90p), frost days (FD), icing days (ID), summer days (SU), and growing season length (GSL). Other extreme temperature indices were ranked in the top 10 since 1961. Meanwhile, for the averaged extreme precipitation indices in China, seven out of the 10 extreme precipitation indices in 2017 were located within the range of one standard deviation, indicating a normal situation for extreme precipitation in 2017.

关键词： Climate warming Extreme temperature Extreme precipitation 2017

Molecular phylogeny of Pamphagidae （Acridoidea, Orthoptera） from China based on mitochondrial cytochrome oxidase II sequences

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Insect Science 2011年第2期18卷 234-244页

作者： Dao-Chuan Zhang hong-Yan Han hong yin Xin-Jiang Li Zhan yin Xiang-Chu yin College of Life Sciences Hebei University Baoding Hebei Province College of Plant Protection Shandong Agncultural University Taian Shandong Province China

Phylogenetic relationships of Pamphagidae were examined using cytochrome oxidase subunit II （COIl） mtDNA sequences （684 bp）. Twenty-seven species of Acridoidea from 20 genera were sequenced to obtain mtDNA data, along with four species from the GenBank nucleotide database. The purpose of this study was analyzing the phylogenetic relationships among subfamilies within Pamphagidae and interpreting the phylogenetic position of this family within the Acridoidea superfamily. Phylogenetic trees were reconstructed using neighbor-joining （NJ）, maximurn parsimony （MP） and Bayesian inference （BI） methods. The 684 bp analyzed fragment included 126 parsimony informative sites. Sequences diverged 1.0%-11.1% between genera within subfamilies, and 8.8%-12.3% between subfamilies. Amino acid sequence diverged 0-6.1% between genera within subfamilies, and 0.4%-7.5% between subfamilies. Our phylogenetic trees revealed the monophyly of Pamphagidae and three distinct major groups within this family. Moreover, several well supported and stable clades were found in Pamphagidae. The global clustering results were similar to that obtained through classical morphological classification： Prionotropisinae, Thrinchinae and Pamphaginae were monophyletic groups. However, the current genus Filchnerella （Prionotropisinae） was not a monophyletic group and the genus Asiotmethis （Prionotropisinae） was a sister group of the genus Thrinchus （Thrinchinae）. Further molec- ular and morphological studies are required to clarify the phylogenetic relationships of the genera Filchnerella and Asiotmethis.

关键词： Acridoidea cytochrome oxidase II gene molecular phylogeny mtDNA,Pamphagidae subfamily

Influence of climatic factors on tree-ring maximum latewood density of Picea schrenkiana in Xinjiang, China

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Frontiers of Earth Science 2016年第1期10卷 126-134页

作者： Yu SUN Lili WANG hong yin Key Laboratory of Land Surface Pattem and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China National Climate Center China Meteorological Administration Beijing 100081 China

The influence of temperature and precipitation on maximum latewood density （MXD） was mainly discussed in this paper, based on the samples of Picea schrenkiana from the Manas River Basin, Xinjiang, China. The correlation analysis between MXD and instrumental records from the Shihezi Meteorological Station showed that the MXD was positively related to the mean maximum temperature throughout the growing season at high elevations. Comparatively, the ring-width at low altitudes was limited by the precipitation in May-June. The composite chronology by MXD sequences was highly correlated with the mean maximum temperature in July- August （r = 0.54,p 〈 0.001）, which was then reconstructed by the composite chronology. The comparative analysis on the reconstructed temperatures, observed values, and drought indices （Is） revealed that precipitation would affect MXD when the absolute value of Is was greater than 1.5a （i.e., ｜Is｜〉 2.5） in the period of 1953-2008 A.D. or close to 1.5σ for 2-3 consecutive years. The response characteristics are linked with the semiarid climate in the study area. In a single year or consecutive years of extreme dryness, the lack of precipitation would limit the thickening oflatewood cell walls and thus impact the MXD. All in all, if a MXD chronology is aimed to reconstruct temperature history, the moisture conditions at the sampling site should be considered prudently.

关键词： Picea schrenkiana tree-ring maximum late-wood density air temperature precipitation

Model Predictive Control for Vapor Compression Cycle of Refrigeration Process

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International Journal of Automation and computing 2018年第6期15卷 707-715页

作者： Xiao-hong yin Shao-Yuan Li Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education of China

A model predictive controller based on a novel structure selection criterion for the vapor compression cycle （VCC） of refrigeration process is proposed in this paper. Firstly, those system variables are analyzed which exert significant influences on the system performance. Then the structure selection criterion, a trade-off between computation complexity and model performance, is applied to different model structures, and the results are utilized to determine the optimized model structure for controller design. The controller based on multivariable model predictive control （MPC） strategy is designed, and the optimization problem for the reduced order models is formulated as a constrained minimization problem. The effectiveness of the proposed MPC controller is verified on the experimental rig.

关键词： Vapor compression refrigeration cycle model structure structure selection criterion model reduction model predictive control.

The Global Convergence of Self-Scaling BFGS Algorithm with Nonmonotone Line Search for Unconstrained Nonconvex Optimization Problems

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Acta Mathematica Sinica,English Series 2007年第7期23卷 1233-1240页

作者： hong Xia yin Dong Lei DU Chinese Academy of Sciences Research Center on Data Technology and Knowledge Economy Department of Mathematics Graduate University of the Chinese Academy of Sciences Faculty of Administration University of New Brunswick

The self-scaling quasi-Newton method solves an unconstrained optimization problem by scaling the Hessian approximation matrix before it is updated at each iteration to avoid the possible large eigenvalues in the Hessian approximation matrices of the objective function. It has been proved in the literature that this method has the global and superlinear convergence when the objective function is convex （or even uniformly convex）. We propose to solve unconstrained nonconvex optimization problems by a self-scaling BFGS algorithm with nonmonotone linear search. Nonmonotone line search has been recognized in numerical practices as a competitive approach for solving large-scale nonlinear problems. We consider two different nonmonotone line search forms and study the global convergence of these nonmonotone self-scale BFGS algorithms. We prove that, under some weaker condition than that in the literature, both forms of the self-scaling BFGS algorithm are globally convergent for unconstrained nonconvex optimization problems.

关键词： nonmonotone line search self-scaling BFGS method global convergence

The Closed Orbits of a Class of Cubic Vector Fields in R^(3)

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Acta Mathematica Sinica,English Series 2020年第12期36卷 1429-1440页

作者： hong Yan yin Da ZHOU Xing An ZHANG School of Mathematics and Statistics Central China Normal UniversityWuhan 430079P.R.China School of Mathematics and Statistics South-Central University for NationalitiesWuhan 430074P.R.China School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,we investigate the isolated closed orbits of two types of cubic vector fields in R^3 by using the idea of central projection transformation,which sets up a bridge connecting the vector field X(x)in R^3 with the planar vector *** have proved that the cubic vector field in R^3 can have two isolated closed orbits or one closed orbit on the invariant *** an application of this result,we have shown that a class of 3-dimensional cubic system has at least 10 isolated closed orbits located on 5 invariant cones,and another type of 3-dimensional cubic system has at least 26 isolated closed orbits located on 13 invariant cones or 26 invariant cones.

关键词： Closed orbit central projection transformation tangent vector field invariant cone

Kinetics of water–isocyanate reaction in N,N-dimethylformamide

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1435-1441页

作者： Zhirong Chen Weitao Yang hong yin Shenfeng Yuan College of Chemical and Biologlical Engineering Zhejiang University Hangzhou 310027 China

The uncatalyzed reaction of p-tolyl isocyanate(p-TI)with water in N,N-dimethylformamide(DMF)was investigated by high performance liquid chromatography(HPLC).The reactions were carried out at different temperatures from 293 K to 323 K,using various molar ratios of water to ***,as a special amide,was proved to be an efficient catalyst for water–isocyanate *** the reaction conditions in this study,substituted urea was the only final product *** appreciable amount of intermediate p-toluidine was *** of the isocyanate group as well as the amine and urea were determined as a function of *** kinetic equations were deduced for each of the substance on the basis of a multistep mechanism,instead of a simple second order reaction as *** constants were calculated using the software ***,the effects of temperature and concentrations of reactants on the reaction rate and amine content were *** activation energy of each step was also determined.

关键词： Kinetics Isocyanate Polyurethane Catalysis HPLC Kinetic modeling