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LARGE-EDDY SIMULATION OF TURBULENT FLOW CONSIDERING INFLOW WAKES IN A FRANCIS TURBINE BLADE PASSAGE

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Journal of Hydrodynamics 2007年第2期19卷 201-209页

作者： wang wen-quan ZHANG Li-xiang YAN Yan GUO Yakun Department of Engineering Mechanics Kunming University of Science and Technology Kunming 650051 China Department of Engineering University of Aberdeen Aberdeen AB24 3UE UK

Turbulent flow in a 3-D blade passage of a Francis hydro turbine was simulated with the Large Eddy Simulation （LES） to investigate the spatial and temporal distributions of the turbulence when strongly distorted wakes in the inflow sweep over the passage, In a suitable consideration of the energy exchanging mechanism between the large and small scales in the complicated passage with a strong 3-D curvature, one-coefficient dynamic Sub-Grid-Scale （SGS） stress model was used in this article. The simulations show that the strong wakes in the inflow lead to a flow separation at the leading zone of the passage, and to form a primary vortex in the span-wise direction. The primary span-wise vortex evolves and splits into smaller vortex pairs due to the constraint of no-slip wall condition, which triggers losing stability of the flow in the passage. The computed pressures on the pressure and suction sides agree with the measured data for a working test turbine model.

关键词： Large Eddy Simulation （LES） turbulent flow,numerical simulation wakes Francis hydro turbine

高质量发展观下学校德育评价的价值旨归与实践路径

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教学与管理 2024年第1期 23-26页

作者：王文权张蓉江苏省苏州市吴江高级中学江苏苏州215200

德育评价作为教育评价的重要组成,对学生的成长有着重要的意义。在新时代教育改革的宏观背景下,教育发展理念开始向高质量迈进,德育评价理念也要与时俱进,符合时代发展主题要义。立德树人倡导以人为本、多元全面的发展观,所以德育评价... 详细信息

德育评价作为教育评价的重要组成,对学生的成长有着重要的意义。在新时代教育改革的宏观背景下,教育发展理念开始向高质量迈进,德育评价理念也要与时俱进,符合时代发展主题要义。立德树人倡导以人为本、多元全面的发展观,所以德育评价也要遵循时代性、整体性和关联性等基本原则,在价值走向上实现从“机械”性向“人文”性转变,从“单一横向”向“多元纵向”转变,从简单“粗犷”式向立体“系统”式转变。基于此,尝试构建兼具科学性和人文性的高质量德育评价体系并探究其实现路径:信息化赋能德育评价,项目化推进德育评价,小组化落实德育评价,示范化助力德育评价。以期为学生成长助力赋能,为新时代人才的培养提供坚实的德育保障。

关键词：德育评价立德树人高质量发展观

STUDY ON TURBULENCE FEATURES NEAR AN OSCILLATING CURVED WALL

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Journal of Hydrodynamics 2007年第3期19卷 255-263页

作者： wang wen-quan ZHANG Li-xiang YAN Yan GUO Yakun Department of Engineering Mechanics Kunming University of Science and Technology Kunming 650051China Department of Engineering University of Aberdeen Aberdeen AB24 3UE UK

In pursuit of possibly true turbulent characters and for exploring a change in turbulence structures near an oscillating flexible wall-curved surface, a sinusoidal oscillation mode was forced to a curved wall, whose vibrations disturbed the flow with an interacting effort between the fluid and the structure. The methodology used was the Large Eddy Simulation （LES） with fluid-structure interaction. The oscillating configuration was on a Fourier sinusoidal mode from the measurements of a Francis hydro turbine blade vibration. The effects of the vibration on the skin friction coefficient, vortices, turbulent coherent structures, and other statistical quantities were studied. The results showed that the streamwise velocity gradient along the normal direction and the normal velocity gradient along the spanwise direction were considerably increased within the viscous sublayer because of the oscillating wall, which additionally caused the low speed streaks to stay away from the wall and the high-momentum flows to be toward the wall. As a result, the streamwise vortices were much more elongated along the downstream to get an energy balance, and the wall skin friction coefficient or the wall friction velocity rose up.

关键词： turbulent flow turbulent structure Large-Eddy Simulation （LES） fluid-structure interaction

Distribution patterns of the contents of five biologically activate ingredients in the root of Scutellaria baicalensis

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Chinese Journal of Natural Medicines 2017年第2期15卷 152-160页

作者： LIU Rong-Xiu SONG Guo-Hu WU Pei-Gen ZHANG Xue-wen HU Hui-Juan LIU Jia MIAO Xiao-Su HOU Zhi-Yan wang wen-quan WEI Sheng-Li School of Chinese Pharmacy Beijing University of Chinese Medicine Chengde Pharmaceutical Co. Ltd Affiliated to China National Group Corp.of Traditional & Herbal Medicine National Engineering Laboratory for Breeding of Endangered Medicinal Materials Institute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences and Peking Union Medical College

As an important herbaceous plant, Scutellaria baicalensis Georgi(Chinese skullcap) is geographically widespread and commonly used throughout the world. In the Chinese medicine market, S. baicalensis has been divided into two primary types, "Ku Qin"(WXR) and "Tiao Qin"(TST). Moreover, TST is also divided into different grades according to the diameter of roots. To explore the distribution patterns of the contents of five biologically activate ingredients(FBAI), we used six-year-old cultivated S. baicalensis and analyzed its growth characteristics as well as the quality difference among different types and diameters in roots. Throughout the entire root, we discovered that contents of the FBAI all initially increased and subsequently decreased from the top to the bottom of the roots. The baicalin content of WXR was less than that of TST. On the contrary, the contents of baicalein, wogonin, and oroxylin A in WXR were up to about two times higher than that in TST. We also found that the 0 to 40 cm part of the S. baicalensis root possessed about 87% of the root biomass and about 92% of the contents of the active ingredients.

关键词： Scutellaria baicalensis Distribution patterns Type Diameter Biologically active ingredients

MeLAZY1c基因调控木薯株型的初步研究

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作物学报 2024年第6期50卷 1514-1524页

作者：望嘉翔郁雪婷李梦桃麦伟涛陈新王文泉海南大学热带农林学院/三亚南繁研究院海南三亚572000 中国热带农业科学院热带生物技术研究所/海南热带农业资源研究院海南省热带农业生物资源保护与利用重点实验室海南海口571101 中国热带农业科学院三亚研究院海南三亚572000

IGT基因家族参与作物株型的调控,LAZY属于IGT的亚家族。以拟南芥6个LAZY成员氨基酸序列为“种子”在木薯基因组中进行比对,在木薯中共鉴定到8个LAZY基因,其中MeLAZY1c与调控分枝角度的AtLAZY1高度同源。基于此,本研究以MeLAZY1c为研究对... 详细信息

IGT基因家族参与作物株型的调控,LAZY属于IGT的亚家族。以拟南芥6个LAZY成员氨基酸序列为“种子”在木薯基因组中进行比对,在木薯中共鉴定到8个LAZY基因,其中MeLAZY1c与调控分枝角度的AtLAZY1高度同源。基于此,本研究以MeLAZY1c为研究对象,利用qRT-PCR分析发现MeLAZY1c在茎中转录水平最高,GUS染色显示pMeLAZY1c在维管束中染色较深。在MeLAZY1c启动子中发现8个光响应/调节元件,随后发现黑暗能显著抑制其表达水平。同时对MeLAZY1c进行基因编辑,获得纯合编辑株系19个,炼苗移栽后观测表型,发现melazy1c突变体植株与SC8野生型相比,其主茎呈现匍匐生长,并且弯曲部位茎外皮细胞形态扭曲变形且大小不一致,近地侧1 mm处细胞数目约是远地侧细胞数量的1.5倍,表明MeLAZY1c在木薯直立/匍匐生长建成方面发挥着重要作用。

关键词：木薯株型调控 LAZY 光响应匍匐基因编辑

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Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang wen-Qing wang Jia-Ping Lin Li-quan wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

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Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： wang Dan Dan wang An Xin ZHANG Xiao Li WEI wen Bin WU Shou Ling ZHAO Xing quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status.Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed.Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

High quality repair of osteochondral defects in rats using the extracellular matrix of antler stem cells

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World Journal of Stem Cells 2024年第2期16卷 176-190页

作者： Yu-Su wang wen-Hui Chu Jing-Jie Zhai wen-Ying wang Zhong-Mei He quan-Min Zhao Chun-Yi Li Institute of Antler Science and Product Technology Changchun Sci-Tech UniversityChangchun 130000Jilin ProvinceChina College of Chinese Medicinal Materials Jilin Agricultural UniversityChangchun 130118Jilin ProvinceChina School of Life Science Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina Department of Oral Implantology Hospital of StomatologyJilin UniversityChangchun 130000Jilin ProvinceChina

BACKGROUND Cartilage defects are some of the most common causes of arthritis.Cartilage lesions caused by inflammation,trauma or degenerative disease normally result in osteochondral defects.Previous studies have shown that decellularized extracellular matrix(ECM)derived from autologous,allogenic,or xenogeneic mesenchymal stromal cells(MSCs)can effectively restore osteochondral integrity.AIM To determine whether the decellularized ECM of antler reserve mesenchymal cells(RMCs),a xenogeneic material from antler stem cells,is superior to the currently available treatments for osteochondral defects.METHODS We isolated the RMCs from a 60-d-old sika deer antler and cultured them in vitro to 70%confluence;50 mg/mL L-ascorbic acid was then added to the medium to stimulate ECM deposition.Decellularized sheets of adipocyte-derived MSCs(aMSCs)and antlerogenic periosteal cells(another type of antler stem cells)were used as the controls.Three weeks after ascorbic acid stimulation,the ECM sheets were harvested and applied to the osteochondral defects in rat knee joints.RESULTS The defects were successfully repaired by applying the ECM-sheets.The highest quality of repair was achieved in the RMC-ECM group both in vitro(including cell attachment and proliferation),and in vivo(including the simultaneous regeneration of well-vascularized subchondral bone and avascular articular hyaline cartilage integrated with surrounding native tissues).Notably,the antler-stem-cell-derived ECM(xenogeneic)performed better than the aMSC-ECM(allogenic),while the ECM of the active antler stem cells was superior to that of the quiescent antler stem cells.CONCLUSION Decellularized xenogeneic ECM derived from the antler stem cell,particularly the active form(RMC-ECM),can achieve high quality repair/reconstruction of osteochondral defects,suggesting that selection of decellularized ECM for such repair should be focused more on bioactivity rather than kinship.

关键词： Osteochondral defect repair Mesenchymal stem cells Extracellular matrix Decellularization Antler stem cells Reserve mesenchymal cells Xenogeneic

In Situ Atomic Reconstruction Engineering Modulating Graphene-Like MXene-Based Multifunctional Electromagnetic Devices Covering Multi-Spectrum

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Nano-Micro Letters 2024年第9期16卷 247-261页

作者： Ting‑Ting Liu Qi Zheng wen‑Qiang Cao Yu‑Ze wang Min Zhang quan‑Liang Zhao Mao‑Sheng Cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China Department of Physics Beijing Technology and Business UniversityBeijing 100048People’s Republic of China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144People’s Republic of China

With the diversified development of big data,detection and precision guidance technologies,electromagnetic(EM)functional materials and devices serving multiple spectrums have become a hot topic.Exploring the multispectral response of materials is a challenging and meaningful scientific question.In this study,MXene/TiO_(2)hybrids with tunable conduction loss and polarization relaxation are fabricated by in situ atomic reconstruction engineering.More importantly,MXene/TiO_(2)hybrids exhibit adjustable spectral responses in the GHz,infrared and visible spectrums,and several EM devices are constructed based on this.An antenna array provides excellent EM energy harvesting in multiple microwave bands,with|S11|up to−63.2 dB,and can be tuned by the degree of bending.An ultra-wideband bandpass filter realizes a passband of about 5.4 GHz and effectively suppresses the transmission of EM signals in the stopband.An infrared stealth device has an emissivity of less than 0.2 in the infrared spectrum at wavelengths of 6-14μm.This work can provide new inspiration for the design and development of multifunctional,multi-spectrum EM devices.

关键词： Graphene-like MXene hybrids Multi-spectral response Multi-function antenna Ultra-wideband bandpass filter Electromagnetic device