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Photonics Research 2022年第1期10卷 I0008-I0013页

作者： XIAODONG SHI JINGJING ZHANG WEICHEN FAN YAOQIN LU nianhua peng KARSTEN ROTTWITT AND HAIYAN OU DTU Fotonik Technical University of DenmarkDK-2800 LyngbyDenmark Institute of Mirco/Nano Optoelectronic and Terahertz Technology Jiangsu UniversityZhenjiang 212013China Surrey Ion Beam Centre Surrey UniversityGuildfordGU27XHUK

The polarization beam splitter is a key component for polarization manipulation in photonic integrated circuits,but it is challenging to design for low-refractive-index optical materials,due to the low birefringence of the *** propose what we believe is a novel compact vertical-dual-slot waveguide-based coupling scheme for silicon carbide,enabling efficient low-birefringence polarization splitting by extensively modulating the transverse-magnetic mode *** numerically and experimentally demonstrate the device in the 4H-siliconcarbide-on-insulator integrated platform,with a small footprint of 2.2 μm × 15 μ*** device,easy to fabricate via a single lithography process as other components on the chip,exhibits low insertion loss of 13 dB,over 80 nm wavelength range.

关键词： polarization waveguides waveguide

An automatic isotropic/anisotropic hybrid grid generation technique for viscous flow simulations based on an artificial neural network

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Chinese Journal of Aeronautics 2022年第4期35卷 102-117页

作者： peng LU nianhua WANG Xinghua CHANG Laiping ZHANG Yadong WU School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China School of Intelligent Manufacturing Engineering Chongqing University of Arts and ScienceChongqing 402160China Stake Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Unmanned Systems Research Center National Innovation Institute of Defense TechnologyBeijing 100071China School of Computer Science and Technology Sichuan University of Science&EngineeringYibin 644005China

Based on the author’s previous research, a novel hybrid grid generation technique is developed by introducing an Artificial Neural Network(ANN) approach for realistic viscous flow simulations. An initial hybrid grid over a typical geometry with anisotropic quadrilaterals in the boundary layer and isotropic triangles in the off-body region is generated by the classical mesh generation method to train two ANNs on how to predict the advancing direction of the new point and to control the grid size. After inputting the initial discretized fronts, the ANN-based Advancing Layer Method(ALM) is adopted to generate the anisotropic quadrilaterals in boundary layers. When the high aspect ratio of the anisotropic grid reaches a specified value, the ANN-based Advancing Front Method(AFM) is adopted to generate isotropic triangles in the off-body computational *** initial isotropic triangles are smoothed to further improve the grid quality. Three typical cases are tested and compared with experimental data to validate the effectiveness of grids generated by the ANN-based hybrid grid generation method. The experimental results show that the two ANNs can predict the advancing direction and the grid size very well, and improve the adaptability of the isotropic/anisotropic hybrid grid generation for viscous flow simulations.

关键词： Advancing front method Advancing layer method Anisotropic quadrilateral grid generation Artificial neural network Isotropic triangular grid generation Machine learning

Adjacent acid sites cooperatively catalyze fructose to 5-hydroxymethylfurfural in a new, facile pathway

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Journal of Energy Chemistry 2020年第8期29卷 112-117,I0004页

作者： Xia Yu Yueying Chu Lei Zhang Hui Shi Mingjiang Xie Luming peng Xuefeng Guo Wei Li nianhua Xue Weiping Ding Key Lab of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Center for Magnetic ResonanceWuhan Institute of Physics and Mathematicsthe Chinese Academy of SciencesWuhan 430071HubeiChina Institute of Theoretical and Computational Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina Department of Chemistry and Catalysis Research Center Technische Universitat MiinchenLichtenbergstr.4.85747 GarchingGermany

To study the effect of adjacent hydroxyl to the active sites, several acid catalysts, i.e. substituted benzoic acids with adjacent carboxyl are employed in the fructose dehydration to 5-hydroxymethylfurfural(HMF).Experimental results reveal that Br?nsted acid sites with adjacent carboxyl present higher catalytic ability than isolated ones. Computational results suggest that the adjacent sites lead to co-interaction on fructose, corresponding more stable transition state and faster HMF formation rate. Based on the enhancement from the adjacent sites, a novel ordered mesoporous carbon(OMC) full of carboxyls in surface is prepared and turns out to be an effective solid catalyst for HMF production from fructose derived from biomass.

关键词： Fructose dehydration Adjacent sites Cooperative catalysis 5-Hydroxymethylfurfural

Genetic and Molecular Characterization of H9N2 Avian Influenza Viruses Isolated from Live Poultry Markets in Hubei Province, Central China, 2013–2017

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Virologica Sinica 2021年第2期36卷 291-299页

作者： Zhibin Hu Fuhu peng Zhenghui Xiong Wanpo Zhang Tingting Li Yuejun Shi Jun Xie Xin Jin Jingjing Huang Hongde Xiao Dingren Bi nianhua Song Zili Li College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070China Hubei Center for Animal Disease Control and Prevention Wuhan 430070China

H9N2 subtype avian influenza virus(AIV)is an influenza A virus that is widely spread throughout Asia,where it jeopardizes the poultry industry and provides genetic material for emerging human *** better understand the epidemicity and genetics of H9 subtype AIVs,we conducted active surveillance in live poultry markets(LPMs)in Hubei Province from 2013 to 2017.A total of 4798 samples were collected from apparent healthy poultry and *** RT-PCR revealed that the positivity rate of influenza A was 26.6%(1275/4798),of which the H9 subtype accounted for 50.3%(641/1275)of the positive *** the 132 H9N2 viral strains isolated,48 representative strains were subjected to evolutionary analysis and *** analysis revealed that all H9N2 viral genes had 91.1%–100%nucleotide homology,clustered with genotype 57,and had high homology with human H9N2 viruses isolated from2013 to 2017 in *** a nucleotide divergence cutoff of 95%,we identified ten distinct H9N2 genotypes that continued to change over *** analysis demonstrated that six H9N2 isolates had additional potential glycosylation sites at position 218 in the hemagglutinin protein,and all isolates had I155 T and Q226 L ***,44 strains had A558 V mutations in the PB2 protein and four had E627 V mutations,along with H9N2 human infection strains A/Beijing/1/2016 and A/Beijing/1/*** results emphasize that the H9N2 influenza virus in Hubei continues to mutate and undergo mammalian adaptation changes,indicating the necessity of strengthening the surveillance of the AIV H9N2 subtype in LPMs.

关键词： Avian influenza H9N2 Genetic variation Phylogenetic analysis Live poultry markets(LPMs)

Exclusively catalytic oxidation of toluene to benzaldehyde in an O/W emulsion stabilized by hexadecylphosphate acid terminated mixed-oxide nanoparticles

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Chinese Journal of Catalysis 2020年第2期41卷 341-349页

作者： Changshun Deng Mengxia Xu Zhen Dong Lei Li Jinyue Yang Xuefeng Guo Luming peng nianhua Xue Yan Zhu Weiping Ding Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093JiangsuChina Luoyang R&D Center of Technology Sinopec Engineering(Group)Co.Ltd.Luoyang 471003HenanChina

A series of hexadecylphosphate acid(HDPA) terminated mixed-oxide nanoparticles have been investigated to catalyze the oxidation of toluene exclusive to benzaldehyde under mild conditions in an emulsion of toluene/water with the catalysts as stabilizers. With the HDPA-Fe2 O3/Al2 O3 as the basic catalyst, a series of transition metals, such as Mn, Co, Ni, Cu, Cr, Mo, V, and Ti, was respectively doped to the basic catalyst to modify the performance of the catalytic system, in expectation of influencing the mobility of the lattice oxygen species in the oxide catalysts. Under normally working conditions of the catalytic system, the nanoparticles of catalysts located themselves at the interface between the oil and water phases, constituting the Pickering emulsion. Both the doped iron oxide and its surface adsorbed hexadecylphosphate molecules were essential to the catalytic system for excellent performances with high toluene conversions as well as the exclusive selectivity to benzaldehyde. Under optimal conditions, ~83% of toluene conversion and >99% selectivity to benzaldehyde were obtained, using molecular oxygen as oxidant and HDPA-(Fe2 O3-Ni O)/Al2 O3 as the catalyst. This process is green and low cost to produce high quality benzaldehyde from O2 oxidation of toluene.

关键词： Toluene oxidation Benzaldehyde Hexadecylphosphate acid Molecular oxygen Pickering

基于机器学习的非结构网格阵面推进生成技术初探

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力学学报 2021年第3期53卷 740-751页

作者：王年华鲁鹏常兴华张来平中国空气动力研究与发展中心空气动力学国家重点实验室四川绵阳621000 西南科技大学信息工程学院四川绵阳621010 重庆文理学院智能制造工程学院重庆402160 国防科技创新研究院无人系统技术研究中心北京100071

网格生成和自适应是制约计算流体力学未来发展的瓶颈问题之一,网格生成自动化和智能化仍是一个需要持续研究的领域.随着高性能计算算力的提升和大数据时代的到来,以机器学习为代表的人工智能方法已经成功应用于包括流体力学在内的多个领... 详细信息

网格生成和自适应是制约计算流体力学未来发展的瓶颈问题之一,网格生成自动化和智能化仍是一个需要持续研究的领域.随着高性能计算算力的提升和大数据时代的到来,以机器学习为代表的人工智能方法已经成功应用于包括流体力学在内的多个领域,革命性地推动了这些领域的发展.本文首先简要综述机器学习方法在非结构网格生成领域的研究进展,分析基于机器学习进行非结构网格生成的关键问题;其次,设计非结构网格样本数据格式并实现了样本数据集的自动提取,通过结合人工神经网络和阵面推进法,初步发展了一种基于人工神经网络的二维非结构网格阵面推进生成方法;最后,采用新发展的方法生成了几个典型二维各向同性非结构三角形网格(二维圆柱、二维NACA0012翼型和30p30n三段翼型),进一步采用合并法生成了相应的三角形/四边形混合网格,并测试了网格质量和生成耗时,结果显示本文方法生成的网格质量可以达到商业软件的水平,且生成效率较传统阵面推进法提高30%.

关键词：机器学习人工神经网络计算流体力学网格生成阵面推进法

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基于人工神经网络的非结构网格尺度控制方法

力学学报 2021年第10期53卷 2682-2691页

作者：王年华鲁鹏常兴华张来平邓小刚中国空气动力研究与发展中心空气动力学国家重点实验室四川绵阳621000 西南科技大学信息工程学院四川绵阳621010 重庆文理学院智能制造工程学院重庆402160 国防科技创新研究院无人系统技术研究中心北京100071 军事科学院北京100091

网格自动化生成和自适应是制约计算流体力学发展的瓶颈问题之一,网格生成质量、效率、灵活性、自动化程度和鲁棒性是非结构网格生成的关键问题.在非结构网格生成中,网格空间尺度分布控制至关重要,直接影响网格生成质量、效率和求解精度... 详细信息

网格自动化生成和自适应是制约计算流体力学发展的瓶颈问题之一,网格生成质量、效率、灵活性、自动化程度和鲁棒性是非结构网格生成的关键问题.在非结构网格生成中,网格空间尺度分布控制至关重要,直接影响网格生成质量、效率和求解精度.采用传统的背景网格法进行空间尺度分布控制需要在背景网格上求解微分方程得到背景网格上的尺度分布,再将网格尺度从背景网格插值到真实空间点,过程十分繁琐且耗时.本文从效率和自动化角度提出两种网格尺度控制方法,首先发展了基于径向基函数(RBF)插值的网格尺度控制方法,通过贪婪算法实现边界参考点序列的精简,提高了RBF插值的效率.同时,还采用人工神经网络进行网格尺度控制,初步引入相对壁面距离和相对网格尺度作为神经网络输入输出参数,建立人工神经网络训练模型,采用商业软件生成二维圆柱和二维翼型非结构三角形网格作为训练样本,通过训练和学习建立起相对壁面距离和相对网格尺度的神经网络关系.进一步实现了二维圆柱、不同的二维翼型的尺度预测,RBF方法和神经网络方法的效率与传统背景网格法相比提高了5~10倍,有助于提高网格生成的效率.最后,将方法推广应用于各向异性混合网格尺度预测,得到的网格质量满足要求.

关键词：人工神经网络网格生成网格尺度背景网格法径向基函数

基于巨噬细胞极化研究“赤芍-附片”治疗慢加急性肝衰竭的作用机制

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中国实验方剂学杂志 2022年第15期28卷 35-41页

作者：谭年花曹钰楠唐陈琴彭杰陈斌湖南中医药大学长沙410208 湖南中医药大学第一附属医院长沙410007

目的:研究赤芍-附片对慢加急性肝衰竭(ACLF)大鼠的治疗作用及其对M1/M2型巨噬细胞极化的影响。方法:将SD雄性大鼠随机分为正常组、模型组、乳果糖组(乳果糖1.8 g·kg^(-1))、中药组(赤芍-附片5.85 g·kg^(-1)),每组6只。采用牛血清白蛋... 详细信息

目的:研究赤芍-附片对慢加急性肝衰竭(ACLF)大鼠的治疗作用及其对M1/M2型巨噬细胞极化的影响。方法:将SD雄性大鼠随机分为正常组、模型组、乳果糖组(乳果糖1.8 g·kg^(-1))、中药组(赤芍-附片5.85 g·kg^(-1)),每组6只。采用牛血清白蛋白皮下及尾静脉注射联合腹腔注射D-半乳糖+脂多糖急性攻击建立ACLF模型,并予以相应药物灌胃1周,空白组和模型组予以蒸馏水灌胃。利用苏木素-伊红(HE)染色观察肝组织病理变化,实时荧光定量聚合酶链式反应(Real-time PCR)、蛋白免疫印迹法(Western blot)、免疫组化等方法比较各组大鼠肝组织CD86、诱导型一氧化氮合酶(iNOS)、CD206、精氨酸酶1(Arg1)mRNA和蛋白表达水平。结果:与正常组比较,模型组大鼠肝组织假小叶形成,肝细胞形态变化、坏死,伴大量炎性细胞浸润,CD86、iNOS mRNA及蛋白表达均显著上调(P<0.01);与模型组比较,各给药组肝组织坏死及炎性浸润均改善,CD86、iNOS mRNA及蛋白表达下调(P<0.01),而CD206、Arg1 mRNA及蛋白表达上调(P<0.05,P<0.01),与乳果糖组比较,中药组上调CD206、Arg1作用更优(P<0.01)。结论:ACLF大鼠存在M1/M2型巨噬细胞极化失衡,失衡向M1方向偏移,赤芍-附片通过促进肝脏巨噬细胞向M2方向极化,抑制M1型巨噬细胞活化,减轻肝衰竭炎症反应.

关键词：慢加急性肝衰竭赤芍附片巨噬细胞极化炎症

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不同时相HBV-ACLF患者外周血Treg/Th17细胞变化及与HBV-DNA相关性研究

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中国病原生物学杂志 2024年第10期19卷 1117-1122页

作者：杜珊谭年花彭杰曾孟晖陈斌湖南中医药大学第一附属医院湖南长沙410007 湖南中医药大学

目的研究不同时相乙肝相关性慢加急性肝衰竭(HBV-ACLF)患者外周血Treg/Th17细胞表达差异,以及与HBV-DNA水平的相关性。方法 60例HBV-ACLF患者分为不同时相,即进展期(Adv-ACLF)28例和平台期(Pla-ACLF)32例,同时纳入慢性乙型肝炎(CHB)患... 详细信息

目的研究不同时相乙肝相关性慢加急性肝衰竭(HBV-ACLF)患者外周血Treg/Th17细胞表达差异,以及与HBV-DNA水平的相关性。方法 60例HBV-ACLF患者分为不同时相,即进展期(Adv-ACLF)28例和平台期(Pla-ACLF)32例,同时纳入慢性乙型肝炎(CHB)患者、健康志愿者(NC)各20例作为对照。流式细胞仪检测各组受试者外周血Treg、Th17细胞频率并计算Treg/Th17比值,流式细胞微球芯片捕获技术(CBA)检测细胞因子转化生长因子(TGF-β)、白介素-10(IL-10)、肿瘤坏死因子(TNF-α)、白介素-17A(IL-17A)、白介素-23(IL-23)水平,实时荧光定量RT-PCR法检测Treg、Th17细胞特异性转录因子FoxP3、ROR-γt mRNA表达;进一步分析不同时相患者Treg、Th17细胞频率及Treg/Th17细胞比值与HBV-DNA水平的相关性。结果与NC组、CHB组比较,HBV-ACLF进展期及平台期患者炎症指标TNF-α、IL-17A、IL-23水平以及ROR-γtmRNA表达明显升高(P<0.01),Th17细胞频率升高、Treg/Th17值下降(P<0.01),Treg/Th17细胞失衡向Th17方向偏移,与平台期比较进展期更严重(P<0.05);进展期HBV-ACLF患者外周血Treg、Th17细胞频率与HBV-DNA水平呈正相关(Treg r=0.516,P=0.005;Th17 r=0.420,P=0.026),但Treg/Th17比值与HBV-DNA水平无相关性。平台期HBV-ACLF患者外周血Treg、Th17细胞频率以及Treg/Th17比值均与HBV-DNA水平无相关性。结论 HBV-ACLF进展期、平台期患者均存在Treg/Th17细胞失衡,进展期患者Treg/Th17失衡较平台期更严重。进展期HBV-ACLF患者Treg、Th17细胞频率与HBV-DNA水平呈正相关。

关键词：肝衰竭 Treg细胞 Th17细胞炎症反应

病例为主导临床血液学检验综合实验教学模式的建立

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实验技术与管理 2016年第8期33卷 181-183页

作者：刘双凤彭克军邓念华成都医学院检验医学院四川成都610500

以临床血液学检验教学为例,对实验教学模式进行改革,在加强基础技能培训的基础上引入病例主导综合实验模式,全面提高学生临床沟通能力、合理选择检验项目、准确操作实验、自我实验质量控制等多方面能力,解决传统教学中重检验轻临床、重... 详细信息

以临床血液学检验教学为例,对实验教学模式进行改革,在加强基础技能培训的基础上引入病例主导综合实验模式,全面提高学生临床沟通能力、合理选择检验项目、准确操作实验、自我实验质量控制等多方面能力,解决传统教学中重检验轻临床、重理论轻实践的问题,也可避免学生孤立学习单一实验项目,提高学生分析问题、解决问题的能力。

关键词：临床血液学检验实验教学综合实验模式