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Coherent structures over riblets in turbulent boundary layer studied by combining time-resolved particle image velocimetry(TRPIV),proper orthogonal decomposition(POD),and finite-time Lyapunov exponent(FTLE)

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Chinese Physics B 2018年第10期27卷 395-404页

作者： shan Li nan Jiang Shaoqiong yang Yongxiang Huang Yanhua Wu School of Mechanical Engineering Tianjin University Tianjin 300072 China Xiamen University Xiamen 361102 China nanyang Technological University Singapore 639798 Republic of Singapore

Time-resolved particle image velocimetry（TRPIV） experiments are performed to investigate the coherent structure＇s performance of riblets in a turbulent boundary layer（TBL） at a friction Reynolds number of 185. To visualize the energetic large-scale coherent structures（CSs） over a smooth surface and riblets, the proper orthogonal decomposition（POD） and finite-time Lyapunov exponent（FTLE） are used to identify the CSs in the TBL. Spatial-temporal correlation is implemented to obtain the characters and transport properties of typical CSs in the FTLE fields. The results demonstrate that the generic flow structures, such as hairpin-like vortices, are also observed in the boundary layer flow over the riblets, consistent with its smooth counterpart. Low-order POD modes are more sensitive to the riblets in comparison with the high-order ones,and the wall-normal movement of the most energy-containing structures are suppressed over riblets. The spatial correlation analysis of the FTLE fields indicates that the evolution process of the hairpin vortex over riblets are inhibited. An apparent decrease of the convection velocity over riblets is noted, which is believed to reduce the ejection/sweep motions associated with high shear stress from the viscous sublayer. These reductions exhibit inhibition of momentum transfer among the structures near the wall in the TBL flows.

关键词： turbulent boundary layer riblets proper orthogonal decomposition finite-time Lyapunov exponent

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光学相干断层扫描血管成像量化分析糖尿病患者黄斑区毛细血管参数

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国际眼科杂志 2024年第1期24卷 10-17页

作者：陆楠杨冬妮谷愉刘健杨世琳郭莹单志明刘丽赵伟秦皇岛市第一医院眼科中国河北省秦皇岛市066000 东北大学秦皇岛分校控制工程学院中国河北省秦皇岛市066004

目的:应用光学相干断层扫描血管成像技术(OCTA)量化2型糖尿病患者黄斑区毛细血管的早期变化。方法:回顾性病例研究。分别纳入49名健康受试者、52例无视网膜病变的2型糖尿病患者(noDR)和43例轻度非增殖性糖尿病视网膜病变(mNPDR)患者,并... 详细信息

目的:应用光学相干断层扫描血管成像技术(OCTA)量化2型糖尿病患者黄斑区毛细血管的早期变化。方法:回顾性病例研究。分别纳入49名健康受试者、52例无视网膜病变的2型糖尿病患者(noDR)和43例轻度非增殖性糖尿病视网膜病变(mNPDR)患者,并得到在黄斑区3 mm×3 mm浅层毛细血管丛和深层毛细血管丛的OCTA图像。去除大血管后分别计算毛细血管灌注密度、血管长度密度(VLD)和平均血管直径(AVD)并进行比较。应用受试者工作特征曲线评估该参数监测2型糖尿病患者视网膜微血管早期改变的能力。结果:比较三组间VLD和AVD,差异均有统计学意义(P<0.001)。与健康受试者相比,noDR组的AVD均显著增加(P<0.05)。mNPDR组患者深层及浅层的VLD较noDR组显著下降(均P<0.01)。深层AVD鉴别noDR组与健康受试者的曲线下面积(AUC)为0.796,鉴别mNPDR组和健康受试者的AUC最高为0.920,其次为深层VLD(AUC=0.899),显著高于其他参数。结论:在糖尿病视网膜病变的临床前阶段,2型糖尿病患者的深层及浅层AVD均显著高于健康人,VLD均显著高于mNPDR患者。与健康人相比,深度AVD较其他参数更能检出noDR患者早期视网膜毛细血管的变化。

关键词：糖尿病视网膜病变光学相干断层扫描血管成像(OCTA) 灌注密度血管长度密度血管直径

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含炔键的聚合物给体材料设计合成及在有机太阳能电池中的性能研究

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高分子学报 2024年第1期55卷 48-57页

作者：李大伟马雪晴崔新悦陈亚男魏楠言行李翠红刘玉强刘亚辉薄志山北京师范大学化学学院能量转换与存储材料北京市重点实验室北京100875 青岛大学纺织服装学院生物多糖纤维成形与生态纺织国家重点实验室青岛266071

利用结构简单、成本低廉的初始原料,设计合成了主链含炔键的聚合物给体材料PBEA-F和PBEA.由于炔键的强吸电子能力,分子的最高占有轨道能级(HOMO)得以降低,使得聚合物的带隙变宽.同时,引入炔键的聚合物给体材料与受体小分子材料BTP-eC9-4... 详细信息

利用结构简单、成本低廉的初始原料,设计合成了主链含炔键的聚合物给体材料PBEA-F和PBEA.由于炔键的强吸电子能力,分子的最高占有轨道能级(HOMO)得以降低,使得聚合物的带隙变宽.同时,引入炔键的聚合物给体材料与受体小分子材料BTP-eC9-4F共混制备有机太阳能电池器件,可实现较低的非辐射能量损失与高的开路电压(open circuit voltage,Voc).最终基于PBEA的器件可得到0.91 eV的Voc、20.70 mA/cm^(2)的短路电流密度(short-circuit current density,Jsc)和10.39%的能量转化效率(power conversion efficiency,PCE),远高于PBEA-F器件的PCE (5.50%).

关键词：有机太阳能电池炔键给体材料简单易合成

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A Potential Chinese Medicine Granule Suppressing ARDS of COVID-19: Keguan-1

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Chinese Journal of Integrative Medicine 2020年第11期26卷 803-804页

作者： ZHONG nan-shan yang Zi-feng JIANG Mei LIANG Jing-yi State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory Healththe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou(510120)China

Recently,a well-designed,exploratory clinical trial on the management of patients with coronavirus disease 2019(COVID-19)by a Chinese medicine(CM)Keguan-1 has been conducted by *** Xiao-he and his colleagues.(1)For the emergency of COVID-19 treatment,conventional new vaccine and new drug development is a money consuming and time demanding process.

关键词： vaccine process. clinical

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Primary pancreatic paraganglioma harboring lymph node metastasis: A case report

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World Journal of Clinical Cases 2021年第27期9卷 8071-8081页

作者： Cui-nan Jiang Xiao Cheng Jing shan Mei yang Yu-Qing Xiao Department of Hepatopancreatobiliary Surgery Chengdu Third People’s HospitalChengdu 610031Sichuan ProvinceChina Department of Pathology Chengdu Third People’s HospitalChengdu 610031Sichuan ProvinceChina Department of Gastroenterology Chengdu Third People’s HospitalChengdu 610031Sichuan ProvinceChina

BACKGROUND Primary pancreatic paragangliomas are extremely rare *** by the diagnostic efficacy of histopathological examination,their malignant behavior is thought to be associated with local invasion or metastasis,with only four malignant cases reported in the literature to *** pancreatic paragangliomas share similar imaging features with other types of pancreatic neuroendocrine neoplasms,they are difficult to diagnose accurately without the support of pathological *** primary pancreatic paragangliomas are rare,especially those accompanied by lymph node metastasis,there is currently no consensus on ***,we report a case of primary pancreatic paraganglioma with lymph node *** SUMMARY A mass located in the pancreatic body was incidentally discovered on computed tomography in a 41-year-old Tibetan *** pancreatectomy was subsequently performed and a 4.1 cm×4.2 cm tumor was found embedded in the body of the pancreas during *** examination confirmed the characteristics of paraganglioma in which the neoplastic chief cells were arranged in a classic Zellballen pattern under hematoxylin-eosin ***,immunohistochemistry demonstrated that the sustentacular cells in the tumor tissue were positive for S-100 protein,and neoplastic cells and pancreatic draining lymph nodes were positive for chromogranin A and synaptophysin;thus,the presence of lymph node metastasis(two of the eight resected pancreatic draining lymph nodes)was also confirmed.A diagnosis of primary pancreatic paraganglioma with lymph node metastasis was finally *** patient remained disease-free for 1 year after the *** A definite diagnosis of pancreatic paraganglioma mainly depends on postoperative histopathological and immunohistochemical *** resection may be the first treatment of choice for patients with primary pancreatic paraganglioma that has metastasized to the lymph nodes.

关键词： Paraganglioma Pancreas Lymph node metastasis Distal pancreatectomy Case report

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Two new ursane-type nortriterpenes from Lonicera macranthoides and their iNOS-inhibitory activities

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Chinese Journal of Natural Medicines 2019年第1期17卷 27-32页

作者： MEI Yu-Dan ZHANG nan ZHANG Wei-yang TANG Jin-shan ZHOU Hua YU yang YAO Xin-Sheng Institute of Traditional Chinese Medicine&Natural Products College of Pharmacy and Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchJinan University XiangXue Academician workstation Xiangxue Pharmaceutical Co.Ltd. College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Faculty of Chinese Medicine Macao University of Science and Technology and State Key Laboratory of Quality Research in Chinese Medicine(Macao University of Science and Technology)

The flower buds of Lonicera macranthoides(shan Yin-Hua), represent an important traditional Chinese medicine and food ingredient. A phytochemical investigation of the 70% EtOH extract of the flower buds of L. macranthoides resulted in the isolation of 12 triterpenoids(1-12), including two new ursane-type nortriterpenes, 2α, 24-dihydroxy-23-nor-ursolic acid(1) and 2α, 4α-dihydroxy-23-nor-ursolic acid(2). Their structures were established by multiple spectroscopic methods and comparison with literature data. All isolated compounds were evaluated for their anti-inflammatory effects in LPS-activated RAW264.7 cells. Compounds 1 and 2 exhibited inhibitory effects on iNOS at the concentration of 30 μmol·L^(-1).

关键词： Lonicerae Flos Lonicera macranthoides Ursane-type nortriterpenes Anti-inflammation iNOS

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Regularization of mathematical model for chip flow angle catastrophe

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Advances in Manufacturing 2021年第4期9卷 568-579页

作者： Shao-nan Zhang Dong-Dong Cheng Liang-shan Xiong School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

The chip flow angle(CFA)catastrophe in double-edged cutting results in a significant reduction in the cutting force,which can benefit the ***,established potential functions(i.e.,cutting power calculation functions)of mathematical models for the CFA catastrophe are presented in the form of transcendental functions with two control parameters and one state parameter,which are extremely complex.A method is proposed herein to realize the regularization of the potential functions and establish mathematical models in a standard form and with complete content for the CFA *** this method,the potential function of the CFA catastrophe is expanded into a k-order Taylor polynomial at each midpoint of N end-to-end equally partitioned intervals of the state parameter using the Taylor function provided in *** potential function after piecewise Taylor expansion is transformed into the same form as the potential function of the standard cusp catastrophe model by truncating the first five terms of the Taylor polynomial and eliminating the third-order term of the state parameter with elementary ***,the regularization of potential function is ***,the regularization of equilibrium surface and bifurcation set can be realized based on the conclusions of the catastrophe *** errors of the potential function,equilibrium surface,and bifurcation set are defined to evaluate the effectiveness of this regularization *** problem of calculating regularization errors is regarded as an optimization ***‘‘simulannealbnd’’function provided in MATLAB is used to solve the *** the proposed method,the regularization of a mathematical model for the CFA catastrophe established by the predecessor is completed;a mathematical model(i.e.,standard cusp catastrophe model)in a standard form and with complete content for the CFA catastrophe is established;and the corresponding regularization errors

关键词： Chip flow angle(CFA)catastrophe Mathematical model Regularization Potential function Catastrophe theory Cusp catastrophe model

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Strategies for reopening in the forthcoming COVID-19 era in China

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National Science Review 2022年第3期9卷 5-6页

作者： Wei-jie Guan nan-shan Zhong State Key Laboratory of Respiratory Disease National Clinical Research Center for Respiratory Disease Guangzhou Institute of Respiratory Health The First Affiliated Hospital of Guangzhou Medical University Guangzhou Medical University Department of Thoracic Surgery Guangzhou Institute for Respiratory Health The First Affiliated Hospital of Guangzhou Medical University Guangzhou Medical University Department of Respiratory and Critical Care Medicine Foshan Second People's HospitalAffiliated Foshan Hospital of Southern Medical University

The transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the culprit pathogen of coronavirus disease 2019 (COVID-19), has resulted in more than 0.43 billion cases and 6 million deaths globally. Compared with other existing variants of concern, the Omicron variant is characterized by significantly greater infectivity (Ro≈6),greater tropism of the upper respiratory tract and lower severity of human infections [1].These characteristics of the Omicron variant are the basis upon which several developed countries are considering reopening.

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大吨位高强高导铜材料的连续化绿色生产

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西安交通大学学报 2024年第5期58卷 19-30页

作者：王亚平王学亮仝毅刚单历元南福东张兆瑞魏帆李小阳杨博黄婧王婷婷西安交通大学物理学院西安710049 西安交通大学教育部物质非平衡合成与调控重点实验室西安710049 西安陕煤启远科技有限公司西安710100 西安交通大学能源与动力工程学院西安710049 西安交通大学热流科学与工程教育部重点实验室西安710049 浙江大学浙江省软体机器人与智能器件研究重点实验室杭州310027

系统研究了高强高导铜材料的强化机理和制造技术,提出了“增强强化相”(提高弥散强化相强度)、“超饱和固溶”(提高基体中弥散强化相浓度)、“柔性包裹铜晶界”(提高材料高温强度等新型强化机制)的创新思路,为同时具有高强度和高导电、... 详细信息

系统研究了高强高导铜材料的强化机理和制造技术,提出了“增强强化相”(提高弥散强化相强度)、“超饱和固溶”(提高基体中弥散强化相浓度)、“柔性包裹铜晶界”(提高材料高温强度等新型强化机制)的创新思路,为同时具有高强度和高导电、高导热的铜基材料成份和显微组织设计提供了理论基础,并在材料学科权威期刊发表相关论文20余篇。发展出高强高导铜的大吨位、连续化、绿色制造技术,实现了全真空大吨位铬锆铜材料的规模生产,具有工艺简单、流程短,所制备的材料结构全致密、显微组织无偏析、性能均匀一致等优点。高强高导铜材料生产项目技术评估价为1500万元,采用混合实施模式(支付西安交通大学300万元现金,发明人技术入股1200万元),与陕煤集团合作成立了发明人技术入股、骨干团队现金参股的混合所有制企业。建成了一期千吨量级生产线,产品在多个国家龙头企业获得规模应用,并即将建设万吨量级生产线,对于国家高铁、芯片、发动机等多个领域关键材料的升级换代具有重要意义。

关键词：高强高导铜强化机制绿色生产技术转化

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Double dehydrogenation of carbocyclic β-dicarbonyl compounds:Koser's reagent can do what iodine(V) reagents can

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Science China Chemistry 2019年第5期62卷 597-601页

作者： shan-shan Liu Li Wang Ya-nan Duan Ao Yu Chi Zhang State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)College of ChemistryNankai University Department of Chemical Engineering and Safety Binzhou University Central Laboratory College of ChemistryNankai University

Koser's reagent is found to be effective in the oxidative double dehydrogenation of various carbocyclic β-dicarbonyl compounds,which constitutes the first example on dehydrogenation reactivity of hypervalent iodine(Ⅲ) reagents for carbocyclic carbonyl compounds. DFT calculations reveal that the rate-determining step is the electrophilic addition of PhI+OH onto enolate of monodehydrogenated product.

关键词： Koser’s reagent double dehydrogenation hypervalent twisting 2,3-benzotropone DFT calculations

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