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Investigation on the width-to-depth ratio effect on turbulent flows in a sharp meandering channel with periodic boundaries using large eddy simulations

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Journal of Hydrodynamics 2024年第4期36卷 662-677页

作者： Bing-chang Zhang dong Xu chun-ning Ji Qi-hua Ran Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China Oceans Graduate School The University of Western AustraliaPerthAustralia State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin300350China

As one of the most common river patterns in nature,meandering river has very complex flow structures in its curved channel bends,including secondary flow structure and primary flow velocity *** date,most of the studies have been carried out on the flow structures in channel bends with unavoidable influences from inlet and outlet boundaries,while a streamwise periodic boundary can overcome this shortcoming *** this paper,large eddy simulations(LES)are employed to investigate the complex flow structures in periodically continuous sharp sine-generated *** influence of width-to-depth ratios and dimensionless curvature radiuses are *** results highlight two additional vortex structures beyond the commonly known secondary currents:The recirculation zone(RZ)and the inner bank cell(IBC).The width-to-depth ratio shows the determining effect on the recirculation *** size of recirculation zone is usually bigger in sine-generated-curve(SGC)channel with large width-to-depth *** biggest recirculation zones appear between the zero-curvature section and the apex *** inner bank cell only forms in SGC channels with small width-to-depth ratios and low *** SGC channel with large width-to-depth ratios,only one circulation cell is observed near the inner *** spatial variations of turbulent features are also revealed by statistical analysis based on the LES sampling *** highlight remarkable effect of width-to-depth ratio and dimensionless curvature radius on the turbulent kinetic energy(TKE)and bed shear stress in SGC channels.

关键词： Sine-generated bend large width-to-depth ratio Reynolds number large eddy simulation(LES) turbulent structure

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Synthesis, Characterization and Properties of Bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} and Crystal Structure of Bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}

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Chemical Research in Chinese Universities 2003年第2期19卷 174-179页

作者： YIN Han dong WANG Chuan hua WANG Yong MA chun lin Department of Chemistry Liaocheng UniversityLiaocheng 252059P.R.China

A series of bis{oxo bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} complexes {[(PhCH 2) 2Sn· (O 2CR)] 2O} 2[where R=2 furyl, 2 (2 furyl)vinyl, 2 (5 tert butyl)furyl, 2 thiophenyl, 2 pyridinyl, 3 pyridinyl , 4 pyridinyl, 3 indolyl, 3 indolylmethyl, 3 indolylpropyl] was synthesized by the reactions of heteroaromatic carboxylic acids with dibenzyltin(Ⅳ) oxide. All the complexes were characterized by elemental analysis, IR, and NMR spectra. The complexes were tested against two human tumour cell lines: MCF 7 and WiDr. The results show that they have higher activities in vitro . The crystal structure of bis{oxo bis[2 furylcarboxylatodibenzyltin(Ⅳ)]}(1) was determined by X ray diffraction. The crystal belongs to monoclinic space group P2 1/n, a =1 6641(2) nm, b =1 25073(18) nm, c =1 7193(3) nm, β= 101 951(2)° , Z=2, R 1=0 0446, wR 2=0 1100. Complex 1 is of a centrosymmetric dimer structure with a four membered central endo cyclic Sn 2O 2 unit in which the bridged oxygen atoms are tri coordinated. Each bridged oxygen atom also connects with an exo cyclic tin atom. The tin atoms are six coordinated and have a coordination geometry of a distorted octahedron. The exo cyclic tin atoms are five coordinated and have a coordination geometry of a monocapped trigonal bipyramid with a very similarly distorted mode. Four carboxylate ligands are divided into two types. The two of the four carboxylate ligands are bidentate and bridged to each pair of exo and endo cyclic tin atoms by using both the oxygen atoms. The other two are monodentate and bridged to each pair of exo and endo cyclic tin atoms but each utilizes one O atom only.

关键词： Dibenzyltin(Ⅳ) Heteroaromatic carboxylate Biological activity Crystal structure

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Preparation and evaluation of a water-in-oil nanoemulsion drug delivery system loaded with salidroside

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Chinese Journal of Natural Medicines 2021年第3期19卷 231-240页

作者： LIANG chun-Xia QI dong-Li ZHANG Li-Na LU Peng LIU Zhi-dong State Key Laboratory of Component-based Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Engineering Research Center of Modern Chinese Medicine Discovery and Preparation Technique Ministry of EducationTianjin University of Traditional Chinese MedicineTianjin 301617China

Salidroside(SAL)is a phenolic substance with high solubility and low permeability,which make it easy to cause the efflux effect of P-glycoprotein and degradation of intestinal flora,resulting in lower *** aim of this study was to develop and optimize a water-in-oil nanoemulsion of SAL(w/o SAL-N)to explore its suitability in oral drug delivery *** this work,SAL-N was successfully prepared by water titration method at K_(m)=1 to construct the pseudo-ternary phase *** characterization including the average viscosity,pH,refractive index,particle size,PDI,TEM,DSC,the content of SAL,and stability study were *** was evaluated for drug release in vitro and pharmacokinetic studies in *** optimized nanoemulsion formulation consisted of Labrafil M 1944 CS(63%),Span-80/Tween-80/EtOH(27%)and 200 mg·mL^(-1) SAL solution(SAL-SOL)(10%).Low viscosity and suitable pH were expected for the *** spherical morphology and nanoscale size of SAL-N enhanced the stability of the nanoemulsion *** vitro drug release showed that SAL-N had a better controlled release property than SAL-SOL at earlier time *** pharmacokinetic studies exhibited that SAL-N had significantly higher in t_(1/2)(2.11-fold),AUC_(0-48 h)(1.75-fold)and MRT0-48 h(2.63-fold)than SAL-SOL(P<0.01).The w/o SAL-N prepared in this work can be effectively delivered via the oral *** can be seen w/o nanoemulsion is a strategy for the drug with polyphenols to delay the release,enhance oral absorption and reduce metabolic rate.

关键词： Salidroside Water-in-oil nanoemulsion Polyphenol Drug release Pharmacokinetics Bioavailability

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Equilibrium Crystallization Temperature of Syndiotactic Polystyrene γ Form

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Chinese Journal of Polymer Science 2018年第6期36卷 749-755页

作者： Hai Wang chun-Ji Wu dong-Mei Cui Yong-Feng Men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The crystallization behavior of syndiotactic polystyrene（s PS） γ form undergoing annealing at various temperatures was investigated using the thermodynamic phase diagram based on Strobl＇s crystallization theory. On the basis of the differential scanning calorimetric results, it was observed that γ form melt-recrystallization occurred at a higher temperature with the increasing lamellar thickness, which resulted from the pre-annealing at the elevating temperature after acetone induced crystallization. Further temperature dependent small-angle X-ray scattering（SAXS） measurement revealed the evolution of the γ form lamellae upon heating until phase transition, involving three different regimes： lamellae stable region（25-90 °C）, melt-recrystallization region（90-185 °C） and pre-phase transition region（185-195 °C）. As a result, recrystallization line, equilibrium recrystallization line and melting line were developed for the s PS γ form crystallization process. Since the melt of γ form involved a γ-to-α/β form phase transition, the melting line was also denoted as the phase transition line in this special case. Therefore, the equilibrium crystallization temperature and melting（phase transition） temperatures were determined at around 390 and 220 °C on the basis of the thermodynamic phase diagram of the s PS γ form.

关键词： Syndiotactic polystyrene γ form Crystallization behavior Equilibrium crystallization temperature Equilibrium melting temperature

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Long-term Visual Tracking: Review and Experimental Comparison

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Machine Intelligence Research 2022年第6期19卷 512-530页

作者： Chang Liu Xiao-Fan Chen chun-Juan Bo dong Wang School of Information and Communication Engineering Dalian University of TechnologyDalian 116024China Dalian Minzu University Dalian 116600China

As a fundamental task in computer vision,visual object tracking has received much attention in recent *** studies focus on short-term visual tracking which addresses shorter videos and always-visible ***,long-term visual tracking is much closer to practical applications with more complicated *** exists a longer duration such as minute-level or even hour-level in the long-term tracking task,and the task also needs to handle more frequent target disappearance and *** this paper,we provide a thorough review of long-term tracking,summarizing long-term tracking algorithms from two perspectives:framework architectures and utilization of intermediate tracking *** we provide a detailed description of existing benchmarks and corresponding evaluation ***,we conduct extensive experiments and analyse the performance of trackers on six benchmarks:VOTLT2018,VOTLT2019(2020/2021),OxUvA,LaSOT,TLP and the long-term subset of ***,we discuss the future prospects from multiple perspectives,including algorithm design and benchmark *** our knowledge,this is the first comprehensive survey for long-term visual object *** relevant content is available at https://***/wangdongdut/Long-term-Visual-Tracking.

关键词： Visual object tracking long-term tracking short-term tracking re-detection online update

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Three-microRNA signature identified by bioinformatics analysis predicts prognosis of gastric cancer patients

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World Journal of Gastroenterology 2018年第11期24卷 1206-1215页

作者： Cheng Zhang chun-dong Zhang Ming-hui Ma dong-qiu dai Department of Gastroenterological Surgery the Fourth Affiliated Hospital of China Medical University

AIM To identify multiple micro RNAs(mi RNAs) for predicting the prognosis of gastric cancer(GC) patients by bioinformatics *** The original microarray dataset GSE93415,which included 20 GC and 20 tumor adjacent normal gastric mucosal tissues,was downloaded from the Gene Expression Omnibus database and used for screening differentially expressed mi RNAs(DEMs).The cutoff criteria were P *** addition,we acquired the mi RNA expression profiles and clinical information of 361 GC patients from The Cancer Genome Atlas database to assess the prognostic role of the *** target genes of mi RNAs were predicted using Target Scan,mi RDB,mi RWalk,and DIANA,and then the common target genes were selected for functional enrichment *** A total of 110 DEMs including 19 up-regulated and 91 down-regulated mi RNAs were identified between 20 pairs of GC and tumor adjacent normal tissues,and the Kaplan-Meier survival analysis found that a threemi RNA signature(mi R-145-3 p,mi R-125 b-5 p,and mi R-99 a-5 p) had an obvious correlation with the survival of GC ***,univariate and multivariate Cox regression analyses indicated that the three-mi RNA signature could be a significant prognostic marker in GC *** common target genes of the three mi RNAs are added up to 108 and used for Gene Functional Enrichment *** Process and Molecular Function analyses showed that the target genes are involved in cell recognition,gene silencing and nucleic acid binding,transcription factor activity,and transmembrane receptor *** Component analysis revealed that the genes are portion of nucleus,chromatin silencing complex,and TORC1/2 *** Pathway analysis indicated that the genes participate in several cancer-related pathways,such as the focal adhesion,PI3 K,and m TOR signaling *** This study justified that a three-mi RNA signature could play a role in predicting the surviv

关键词： Gene functional enrichment Prognosis Bioinformatic analysis Differentially expressed miRNAs Gastric cancer

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Microstructure and magnetic properties of SmCo_(5) sintered magnets

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Rare Metals 2020年第11期39卷 1295-1299页

作者： dong-Tao Zhang Rong-chun Zhu Ming Yue Wei-Qiang Liu College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

SmCo_(5)sintered magnets with good thermal stability are mainly used in high-temperature *** this study,two types of SmCo_(5) powders with different nominal z values were mixed and synthesized into SmCo_(5) magnets by the traditional powder metallurgy *** magnetic properties of the SmCo_(5) sintered magnet are maximum energy product of(BH)_(max)=172.29 kJ·m^(-3),remanence of B_(r)=7.47×10^(5)A·m^(-1)and coercivity of H_(ci)=2.42 *** results show that there are three coexisting phases in the magnet,which are SmCo_(5)phase,Sm_(2)Co_(7)phase and Sm_(2)O_(3)*** microstructural observation indicates that the average grain size in the magnet is about 8μm,and the high coercivity of this magnet is attributed to these fine grains.X-ray diffraction(XRD)and electron backscatter diffraction(EBSD)results indicate that the magnet has a well-aligned(00l)orientation texture.

关键词： SmCo_(5) Sintered magnets Magnetic properties

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Signal transducer and activator of transcription is involved in the expression regulation of ecdysteroid-induced insulin-like growth factor-like peptide in the pupal wing disc of silkworm, Bombyx mori

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Insect Science 2020年第6期27卷 1186-1197页

作者： Xiao-Juan Zhang dong-dong Li Guan-Feng Xu Ya-Qing Chen Si-chun Zheng Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina Guangzhou Key Laboratory of Insect Development Regulation and Applied Research Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina

In insects,20-hydroxyecdysone(20E)and insulin-like growth factor-like peptides(IGFLPs)regulate the development o f imaginal ***,how IGFLPs are up-regulated to impact the development of the pupal wing disc is still *** this study,we investigated the expression regulation of IGFLP in the pupal wing disc of silkworm,Bombyx *** confirmed that *** IGFLP(BmIGFLP)was mainly expressed in the pupal wing disc and the expression of BmIGFLP could be significantly induced by *** analysis of BmIGFLP promoter sequence revealed three m-regulation elements(CREs)of signal transducer and activator of transcription(STAT),which is a key component in the Janus-activated kinase/STAT *** activity assays showed that two CREs enhanced the transcriptional activity o f *** mobility shift and chromatin immunoprecipitation assays demonstrated that BmSTAT proteins in the nuclear extracts o f *** pupal wing discs and BmN cells could only bind to the STAT CRE3,indicating that STAT CRE3 activated by BmSTAT enhances BmIGFLP expression at pupal *** 20E could not enhance the expression of BmSTAT,20E enhanced the nucleus translocation o f BmSTAT to bind with the STAT CRE3 in the BmIGFLP *** increase of transcriptional activity of the STAT CRE3 by overexpression of BmSTAT and addition o f 20E in BmN cells confirmed this *** together,all data indicate that BmSTAT is one o f the transcription factors activating 20E-induced BmIGFLP expression in the pupal wing disc.

关键词： Bombyx mori expression regulation IGFLP 20-hydroxyecdysone STAT

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First-Order System Least-Squares Methods for a Flux Control Problem by the Stokes Flow

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Communications in Computational Physics 2010年第4期7卷 738-758页

作者： Soorok Ryu Sang dong Kim Hyung-chun Lee Department of Industrial and Applied Mathematics Kyungpook National UniversityDaegu 702-701Korea Department of Mathematics Kyungpook National UniversityDaegu 702-701Korea Department of Mathematics Ajou UniversitySuwon 443-749Korea

This article deals with a first-order least-squares approach to the solution of an optimal control problem governed by Stokes *** with our earlier work on a velocity control by the Stokes flow in[***,H.-*** and ***,SIAM ***.,47(2009),pp.1524-1545],we recast the objective functional as a H1 seminorm in the velocity control *** introducing a velocity-flux variable and using the Lagrange multiplier rule,a first-order optimality system is *** show that the least-squares principle based on L2 norms applied to this system yields the optimal discretization error estimates for each variable in H1 norm,including the velocity *** numerical tests,multigrid method is employed to the discrete algebraic system,so that the velocity and flux controls are obtained.

关键词： Optimal control optimization least-squares finite element methods Lagrange multiplier Stokes equations.

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The effect of amylose on kernel phenotypic characteristics,starch-related gene expression and amylose inheritance in naturally mutated high-amylose maize

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Journal of Integrative Agriculture 2020年第6期19卷 1554-1564页

作者： ZHANG Xu-dong GAO Xue-chun LI Zhi-wei XU Lu-chun LI Yi-bo ZHANG Ren-he XUE Jiquan GUO dong-wei Key Laboratory of Biology and Genetic Improvement of Maize in Arid Area of Northwest Region Ministry of Agriculture and Rural Affairs/College of AgronomyNorthwest A&F UniversityYa ng ling 712100P.R.China Institute of Crop Science Quality of Plant ProductsUniversity of HohenheimStuttgart 70599Germany

High-amylose maize starch has great pote ntial for widespread in dustrial use due to its ability to form strong gels and film and in the food processi ng field,thus servi ng as a resista nt starch ***,there is still a substa ntial shortage of high-amylose maize due to the limitation of natural germplasm resources,although the well-known amylose extender(ae)gene mutants have bee n found to produce high-amylose maize lines since *** this con text,high-amylose maize lines(13 inbreds and 18 hybrids)originating from a natural amylose mutant in our testing field were utilized to study the correlation between amylose content(AC)and phenotypic traits(kernel morphology and endosperm glossiness),grain filling characteristics,gene expression,and amylose *** results showed that AC was negatively correlated with total starch con tent but was not correlated with grain phe no types,such as kernel full ness,kernel morphology and endosperm *** lines with higher amylose had a greater grain filling rate than that of the controI(B73)during the first 20 days after pollination(DAP).Both starch debranching enzyme(DBE)groups and starch branching enzyme lib(SBEIIb)groups showed a greater abundance in the control(B73)than in the high-amylose maize *** parents directly predicted AC of Fv which was moderately positively correlated with the F2 generation.

关键词： starch biosynthesis amylose inheritance high-amylose maize grain filling rate

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