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Chinese Journal of Aeronautics 2023年第3期36卷 63-79页

作者： Shuhua ZENG Zhenyu YUAN wenwen zhao Weifang CHEN School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China

To predict aeroheating performance of hypersonic vehicles accurately in thermochemical nonequilibrium flows accompanied by rarefaction effect,a Nonlinear Coupled Constitutive Relations(NCCR)model coupled with Gupta’s chemical models and Park’s two-temperature model is firstly proposed in this *** typical cases are intensively investigated for further validation,including hypersonic flows over a two-dimensional cylinder,a RAM-C II flight vehicle and a type HTV-2 flight *** results predicted by NCCR solution,such as heat flux coefficient and electron number densities,are in better agreement with those of direct simulation Monte Carlo or flight data than Navier-Stokes equations,especially in the extremely nonequilibrium regions,which indicates the potential of the newly-developed solution to capture both thermochemical and rarefied nonequilibrium *** comparisons between the present solver and NCCR model without a two-temperature model are also conducted to demonstrate the significance of vibrational energy source term in the accurate simulation of high-Mach flows.

关键词： Hypersonic flow Nonlinear coupled constitutive relations Rarefied gas Thermochemical nonequilibrium effect Vibrational excitation

Neocryptotanshinone inhibits lipopolysaccharide-induced inflammation in RAW264.7 macrophages by suppression of NF-κB and iNOS signaling pathways

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Acta Pharmaceutica Sinica B 2015年第4期5卷 323-329页

作者： Chuanhong Wu wenwen zhao Xuenong Zhang Xiuping Chen State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of Macao

Neocryptotanshinone(NCTS) is a natural product isolated from traditional Chinese herb Salvia miltiorrhiza Bunge. In this study, we investigated its anti-inflammatory effects in lipopolysaccharide(LPS)-stimulated mouse macrophage(RAW264.7) cells. MTT results showed that NCTS partly reversed LPS-induced cytotoxicity. Real-time PCR results showed that NCTS suppressed LPS-induced mRNA expression of inflammatory cytokines, including tumor necrosis factor α(TNFα), interleukin-6(IL-6) and interleukin-1β(IL-1β). Moreover, NCTS could decrease LPS-induced nitric oxide(NO)production. Western blotting results showed that NCTS could down-regulate LPS-induced expression of inducible nitric oxide synthase(iNOS), p-IκBα, p-IKKβ and p-NF-κB p65 without affecting cyclooxygenase-2(COX-2). In addition, NCTS inhibited LPS-induced p-NF-κB p65 nuclear *** conclusion, these data demonstrated that NCTS showed anti-inflammatory effect by suppression of NF-κB and iNOS signaling pathways.

关键词： Neocryptotanshinone Inflammation NF-κB Inducible nitric oxide synthase

Tobacco control challenges in China: Big data analysis of online tobacco marketing information

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International Journal of Nursing Sciences 2020年第S01期7卷 52-60页

作者： Xiuli Wang Ying Xiong wenwen zhao School of New Media Peking UniversityDirector of Center for Social Media ResearchBeijingChina

Objective:To develop tobacco control strategies by analyzing online tobacco marketing information in ***:Using web-crawler software,this study acquired 106,485 pieces of online tobacco marketing information published on 11 different Internet platforms including Weibo,WeChat,Baidu,etc.,from January-June *** data were used to investigate the characteristics and social networks of online tobacco marketing via content and social network ***:The total volume of online tobacco marketing during the study period was high,showing a positive *** all the marketing subjects,those involving"flavor capsule","Marlboro",and"Esse"were the most *** Weibo platform had the highest volume of online tobacco marketing information as well as the largest proportion of explicit marketing *** was followed by other social media platforms such as Baidu Search,Baidu Tieba,and Xiaohongshu,where implicit marketing information *** overall network structure of tobacco websites exhibited a significant centralization feature,where traditional and novel tobacco websites formed two clusters with almost no *** China Tobacco Science and Education Website(http://***/)and E-Cigarette Home(http://***/)were the two nodes of the highest degree centrality within the respective"circle",while the China Tobacco Monopoly Bureau Website(http://***/)was the node with the highest closeness *** contrast,Baidu Tieba's overall network structure was more decentralized,and the degree of correlation between different nodes was relatively ***:Online tobacco marketing demonstrated high volumes and wide coverage,and an intertwined network,thereby creating major obstacles for tobacco *** address this issue,the government should strengthen network supervision of tobacco marketing and revise its current ***,Internet platforms should improve self-regulation by compre

关键词： Big data China Internet Marketing Social media Social networking Tobacco Tobacco products

Data-driven nonlinear constitutive relations for rarefied flow computations

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Advances in Aerodynamics 2021年第1期3卷 540-558页

作者： wenwen zhao Lijian Jiang Shaobo Yao Weifang Chen School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027People’s Republic of China

To overcome the defects of traditional rarefied numerical methods such as the Direct Simulation Monte Carlo(DSMC)method and unified Boltzmann equation schemes and extend the covering range of macroscopic equations in high Knudsen number flows,data-driven nonlinear constitutive relations(DNCR)are proposed first through the machine learning *** on the training data from both Navier-Stokes(NS)solver and unified gas kinetic scheme(UGKS)solver,the map between responses of stress tensors and heat flux and feature vectors is established after the training *** the obtained off-line training model,new test cases excluded from training data set could be predicated rapidly and accurately by solving conventional equations with modified stress tensor and heat ***,conventional one-dimensional shock wave cases and two-dimensional hypersonic flows around a blunt circular cylinder are presented to assess the capability of the developed method through various comparisons between DNCR,NS,UGKS,DSMC and experimental *** improvement of the predictive capability of the coarsegraining model could make the DNCR method to be an effective tool in the rarefied gas community,especially for hypersonic engineering applications.

关键词： Data-driven method Shock wave structure Hypersonic flow Rarefied gas dynamics

Combustion synthesis and characterizations of Sm2O3 doped zirconolite-rich waste forms with CuO as oxidant

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Journal of Rare Earths 2019年第12期37卷 1359-1365页

作者： Kuibao Zhang Dan Yin Zongsheng He Jiali Xue wenwen zhao Haibin Zhang State Key Laboratory of Environment-friendly Energy Materials Southwest University of Science and TechnologyMianyang 621010China National Defense Key Discipline Lab of Nuclear Waste and Environmental Safety Southwest University of Science and TechnologyMianyang 62W10China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

Zirconolite is one of the most important matrix materials for nuclear waste *** this study,Sm was employed as the surrogate of trivalent ***-doped zirconolite-rich waste forms were readily prepared by combustion synthesis(CS)using CuO as the *** different schemes with or without Al2O3 as the charge compensator were carried out *** results demonstrate that Al2O3 addition results in complex phase *** the other hand,the samples without Al2O3 addition show desirable products of zirconolite and *** EDX analysis shows that Sm is concurrently incorporated into the Ca and Zr sites of zirconolite,which transforms to pyrochlore structure with high Sm2O3 *** aqueous durability of representative Sm-doped sample(Sm-0.6)was *** 42 days normalized leaching rate of Sm is as low as 6.41×10-7 g/(m2 d),which exhibits high durability of Sm-doped sample.

关键词： Combustion synthesis Sm2O3 Zirconolite Pyrochlore Aqueous durability Rare earths

Electrospun radially oriented berberine-PHBV nanofiber dressing patches for accelerating diabetic wound healing

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Regenerative Biomaterials 2024年第5期3卷 135-148页

作者： Qiuyu Wang Sai Zhang Jiayi Jiang Shaojuan Chen Seeram Ramakrishna wenwen zhao Fan Yang Shaohua Wu College of Textiles&Clothing Qingdao UniversityQingdao 266071China College of Textile and Clothing Dezhou UniversityDezhou 253023China State Key Laboratory of Bio-Fibers and Eco-Textiles Qingdao UniversityQingdao 266071China Department of Mechanical Engineering Center for Nanotechnology&SustainabilityCollege of Design and EngineeringNational University of SingaporeSingapore 117576Singapore School of Basic Medicine Qingdao UniversityQingdao 266071China

A dressing patch made of radially oriented poly(3-hydroxybutyrateco-3-hydroxyvalerate)(PHBV)nanofibers was successfully manufactured with a modified electrospinning *** aselectrospun PHBV radially oriented nanofiber dressing patch exhibited uniform and bead-free nanofibrous morphology and innovative radially oriented arrangement,which was demonstrated to possess obviously improved mechanical property,increased surface hydrophilicity and enhanced biological properties compared to the PHBV nanofiber dressing patch control with traditionally randomly oriented ***,it was found that the radially oriented pattern could induce the cell migration from the periphery to the center along the radially oriented nanofibers in a rapid *** further improve the biofunction of PHBV radially oriented nanofiber dressing patch,berberine(Beri,an isoquinoline alkaloid)with two different concentrations were encapsulated into PHBV nanofibers during electrospinning,which were found to present a sustained drug release behavior for nearly one ***,the addition of Beri could impart the dressing patch with excellent anti-inflammatory property by significantly inhibiting the secretion of pro-inflammatory factors of M1 macrophages,and also showed an additive influence on promoting the proliferation of human dermal fibroblasts(HDFs),as well as inhibiting the growth of ***,*** and ***,compared with the Beri-free dressing *** the animal studies,the electrospun PHBV radially oriented nanofiber dressing patch loading with high Beri content was found to obviously accelerate the healing process of diabetic mouse full-thickness skin wound with shortened healing time(100%wound closure rate after 18 days’treatment)and improved healing quality(improved collagen deposition,enhanced re-epithelialization and neovascularization and increased hair follicles).In all,this study reported an innovative therapeutic strategy integrating the excellent phys

关键词： electrospinning radial alignment drug delivery wound dressing diabetic wound

Efficient Stabilization of Na Storage Reversibility by Ti Integration into O′3-Type NaMnO_(2)

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Energy Material Advances 2021年第1期2021卷 143-154页

作者： Takuro Sato Kazuki Yoshikawa wenwen zhao Tokio Kobayashi Hongahally Basappa Rajendra Masao Yonemura Naoaki Yabuuchi Department of Chemistry and Life Science Yokohama National University79-5 TokiwadaiHodogaya-kuYokohamaKanagawa 240-8501Japan Department of Applied Chemistry Tokyo Denki UniversityAdachiTokyo 120-8551Japan Elements Strategy Initiative for Catalysts and Batteries Kyoto Universityf1-30 Goryo-OharaNishikyo-kuKyoto 615-8245Japan Institute of Materials Structure Science High Energy Accelerator Research OrganizationTsukubaIbaraki 305-0801Japan Department of Materials Structure Science Sokendai(The Graduate University for Advanced Studies)203-1 ShirakataTokaiIbaraki 319-1106Japan Advanced Chemical Energy Research Center Yokohama National University79-5 TokiwadaiHodogaya-kuYokohamaKanagawa 240-8501Japan

The development of an energy storage system with abundant elements is a key challenge for a sustainable society,and the interest of Na intercalation chemistry is extending throughout the research ***,the impact of Ti integration into NaMnO2 in a binary system of x NaMnO2–(1–x)TiO2(0:5≤x≤1)is systematically examined for rechargeable Na battery *** NaMnO2,which is classified as an in-plane distorted O′3-type layered structure,delivers a large initial discharge capacity of approximately 200 mAhg-1,but insufficient capacity retention is observed,most probably associated with dissolution of Mn ions on electrochemical ***-substituted samples show highly improved electrode performance as electrode ***,the appearance of a sodium-deficient phase,Na4Mn4Ti5O18 with a tunnel-type structure,is observed for Ti-rich *** the samples in this binary system,Na0.8Mn0.8Ti0.2O2(x=0:8),which is a mixture of a partially Ti-substituted O′3-type layered oxide(Na0.88Mn0.88Ti0.12O2)and tunnel-type Na4Mn4Ti5O18 as a minor phase elucidated by Rietveld analysis on both neutron and X-ray diffraction patterns,shows good electrode performance on the basis of energy density and *** phases are electrochemically active as evidenced by in situ X-ray diffraction study,and the improvement of reversibility originates from the suppression of Mn dissolution on electrochemical *** these results,the feasibility of Mn-based electrode materials for high-energy rechargeable Na batteries made from only abundant elements is discussed in detail.

关键词： electrode system Storage

Political Skill, Gender, and Social Network Positioning of Chinese Employees

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Frontiers of Business Research in China 2015年第3期9卷 400-419页

作者： Jun Yang Chao Liu Qianghong Zhang wenwen zhao Chenxi Wang 1. School of Business Renmin University of China Beijing 100872 China2. School of Business Renmin University of China Beijing 100872 China3. School of Business Renmin University of China Beijing 100872 China4. School of Business Renmin University of China Beijing 100872 China5. School of Business Renmin University of China Beijing 100872 China

We collected data from 156 Chinese hospital employees to investigate how political skill and gender affect their advice and friendship network positioning. We found employees with high levels of political skill are more likely to proactively seek friendship ties, while political skill does not affect employees＇ advice networks overall. In addition, results show that for men, those with high levels of political skill have lower in-degree centrality in advice and friendship networks than those with less political skill. Political skill does not affect women＇s network positions.

关键词： political skill gender social networks Chinese organizations

Theoretical study on S-, N-doped anatase TiO2:the visible-light-driven photocatalysts

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Theoretical study on S-, N-doped anatase TiO2:the visible-li...

第二届国际计算科学与工程国际学术研讨会

作者： wenwen zhao FengHui Tian Xiaobin Wang Linhuan zhao Linhua Xia ChengBu Liu Institute of Computational Science and Engineering Laboratory of New Fiber Materials and Modern Textile The Growing Base for State Key Laboratory Qingdao University Institute of Theoretical Chemistry Shandong University

Density functional theory （DFT） calculations are used to characterize the doping effect of S, N elements substituting for oxygen in anatase TiO 2 . Three cases, including pure, S-doped and N-doped TiO 2 , were treated. For the two doping cases, DFT calculations show that the doping elements could lower the band gap of TiO 2 effectively. Excitations from the extended valence band to the conduction band may be responsible for the red shift of absorption edge observed in S, N-doped TiO 2 . Band gap obtained in TiO 2-x S x was narrower than that in TiO 2-x N x . Both Mulliken population and geometry structure analysis indicated that the carriers should have larger mobility in TiO 2-x S x . It is expected that TiO 2-x S x might be a good photocatalyst comparable to TiO 2-x N x .

关键词： Anionic doped anatase TiO 2 TiO 2-x N x TiO 2-x S x Density functional theory Visible-light-driven photocatalyst

来源： cnki会议评论

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基于流量优化的可靠服务功能链部署方法

系统工程与电子技术 2021年第10期43卷 3017-3025页

作者：阳勇孟相如康巧燕赵文文空军工程大学信息与导航学院陕西西安710077

针对网络功能虚拟化环境中服务功能链部署的资源开销问题,提出一种基于流量优化的可靠服务功能链部署方法。首先,根据虚拟链路流量变化对虚拟网络功能进行聚合,使带宽需求大的虚拟链路部署到底层网络后,其流量变为服务器的内部流量。其... 详细信息

针对网络功能虚拟化环境中服务功能链部署的资源开销问题,提出一种基于流量优化的可靠服务功能链部署方法。首先,根据虚拟链路流量变化对虚拟网络功能进行聚合,使带宽需求大的虚拟链路部署到底层网络后,其流量变为服务器的内部流量。其次,综合考虑可靠性、综合时延以及拓扑属性,利用离差最大化的多指标决策算法对物理节点进行评价,并使用链路约束降低流量的乒乓效应。最后,采用k-最短路径算法将虚拟链路部署到满足带宽需求的物理链路上。仿真实验表明,所提方法在保证服务功能链可靠性的基础上,对长期收益开销比、映射成功率、端到端时延以及带宽开销有较大优化。

关键词：网络功能虚拟化服务功能链部署资源开销乒乓效应拓扑与时延感知