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A Lower Semicontinuity Result for Some Integral Functionals in the Space SBD

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Acta Mathematicae Applicatae Sinica 2008年第2期24卷 297-304页

作者： Zhong-xue lu Xiao-ping Yang Min-ling Zheng School of Mathematical Science Xuzhou Normal University Xuzhou 221116 China School of Science Nanjing University of Science and Technology Nanjing 210094 China School of Science Huzhou Teacher College Huzhou 313000 China

In this paper, we obtain a lower semicontinuity result with respect to the strong L1-convergence of the integral functionals F（u,Ω）=Ωf（x,u（x）,εu（x））dx defined in the space SBD of special functions with bounded deformation. Here Su represents the absolutely continuous part of the symmetrized distributional derivative Eu. The integrand f satisfies the standard growth assumptions of order p 〉 1 and some other conditions. Finally, by using this result,we discuss the existence of an constrained variational problem.

关键词： SBD space integral functionals lower semicontinuity

Photoluminescence Properties of Nanocrystalline 3C-SiC Films

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Chinese Journal of Aeronautics 2006年第B12期19卷 215-219页

作者： YUWei lu xue-qin lu Wan-bing HAN Li FU Guang-sheng College of Physics Science and Technology Hebei University Baoding 071002 China

Nanocrystalline （nc） 3C-SiC films on the Si substrate were prepared by the helicon wave plasma enhanced chemical vapor deposition （HW-PECVD） technique. With the SiH4-CH4 gas flow ratio changing, the films exhibit different photoluminescence （PL） characteristics. Under the stoichiometric condition, the PL peak redshift from 470 nm to 515 nm is detected with the increase of excitation wavelength, which can be attributed to the quantum confinement effect radiation of 3C-SiC nanocrystals of different sizes. However, the appearance of an additional PL band at 436 nm in Si-rich film might be sourced back to the excess of Si defect centers in it. This is also the case for C-rich film for its PL band lying at 570 nm. The results above quoted indicate an important influence of gas flow ratio on the PL properties of the SiC films providing an effective guidance for analyzing the luminescence mechanism and exploring the high-efficiency light emission of the SiC films.

关键词： SiC film photoluminescence quantum confinement effect defect

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高等教育数字化转型与教育理念的关系研究

教育教学论坛 2024年第31期 29-32页

作者：燕小斌顾玉芬卢学峰兰州理工大学材料科学与工程学院甘肃兰州730050

随着数字技术在高等教育领域的广泛应用和深度融合,高等教育必然面临着数字化转型的新机遇,通过对当今高等教育教学中不同层次的数字化转型实践与发展现状进行系统分析,主要对数字化转型实践中所呈现出的新型教学关系背后的教育理念进... 详细信息

随着数字技术在高等教育领域的广泛应用和深度融合,高等教育必然面临着数字化转型的新机遇,通过对当今高等教育教学中不同层次的数字化转型实践与发展现状进行系统分析,主要对数字化转型实践中所呈现出的新型教学关系背后的教育理念进行深入分析与探讨,分析研究表明高等教育教学的数字化转型解构了以知识传授为先的传统教育理念,助推了契合信息时代的以学为中心的高等教育理念的重塑与构建,因此,高等教育的数字化转型是信息时代里高等教育高质量发展值得深入推进的重要路径和新方向。

关键词：高等教育数字化转型以学为中心

INVESTIGATION OF AIRSHIP AEROELASTICITY USING FluID- STRUCTURE INTERACTION

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Journal of Hydrodynamics 2008年第2期20卷 164-171页

作者： LIU Jian-min lu Chuan-jing xue Lei-ping Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200240 China

Due to the flexibility of the envelope of large stratosphere airships, the aerodynamic solution of such airship is closely related to its shape and the external aerodynamic forces which lead to the structural deformation. It is essentially one of the Fluid-Structure Interaction （FSI） problems. This article aims at the numerical investigation of nonlinear airship aeroelasticity in consideration of aerodynamics and structure coupling, using an iteration method. The three-dimensional flow around the airship was numerically studied by means of the SIMPLE method based on the finite volume method. Nonlinear finite element analysis was employed for geometrically nonlinear deformation of the airship shape. Comparison of aerodynamic parameters and the pressure distribution between rigid and aeroelastic models was conducted when an airship is in a trimmed flight state in specified flight conditions. The effect ofaeroelasticity on the airship aerodynamics was detailed.

关键词： airship three-dimensional flow elastic deformation fluid-structure interaction

The Mechanisms of Brassinosteroids＇ Action： From Signal Transduction to Plant Development

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Molecular Plant 2011年第4期4卷 588-600页

作者： Cang-Jin Yang Chi Zhang Yang-Ning lu Jia-Qi Jin xue-lu Wang State Key Laboratory of Genetic Engineering and Institute of Plant Biology School of Life Sciences Fudan University Shanghai 200433 People's Republic of China

Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid （BR） biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating the importance of both BR biosynthesis and the signaling pathway in regulating these biological processes. Recently, using genetics, proteomics, genomics, cell biology, and many other approaches, more components involved in the BR signaling pathway were identified. Furthermore, the physiological, cellular, and molecular mechanisms by which BRs regulate various aspects of plant development, are being discovered. These include root development, anther and pollen development and formation, stem elongation, vasculature differentiation, and cellulose biosynthesis, suggesting that the biological functions of BRs are far beyond promoting cell elongation, This review will focus on the up-to-date progresses about regulatory mechanisms of the BR signaling pathway and the physiological and molecular mechanisms whereby BRs regulate plant growth and development.

关键词： Arabidopsis brassinosteroid cross-talk phosphorylation plant development signaling pathway stresses.

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智慧管网对标策略研究

标准科学 2024年第4期 21-25页

作者：薛鲁宁李莉陈钻崔秀国侯学瑞国家管网集团浙江省天然气管网有限公司国家石油天然气管网集团有限公司科学技术研究总院分公司国家管网集团东部原油储运有限公司

本文在分析智慧管网建设关键技术的基础上,结合对标管理的一般方法,提出了智慧管网对标的基本策略。智慧管网对标涵盖管理和技术两方面内容,管理对标包括智慧系统的定义内涵、发展战略、建设目标、智慧化水平评价、企业组织架构改革、... 详细信息

本文在分析智慧管网建设关键技术的基础上,结合对标管理的一般方法,提出了智慧管网对标的基本策略。智慧管网对标涵盖管理和技术两方面内容,管理对标包括智慧系统的定义内涵、发展战略、建设目标、智慧化水平评价、企业组织架构改革、科研投入、投资收益以及标准体系等内容;技术对标包括物联网技术、数字孪生技术和知识库建设技术3类通用技术和智能化提升技术。对于管理对标和通用技术对标以一般性对标和行业对标为主,辅以竞争性对标,对于智能化提升技术对标,以竞争性对标为主,辅以一般性对标和行业对标。

关键词：智慧管网对标物联网数字孪生知识库

In Situ Variation of Interpenetrating Polymer Network Topology using a Photolabile Connector

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Chinese Journal of Polymer Science 2022年第11期40卷 1317-1322页

作者： Xin-Hong Xiong lu-lu xue Sheng Wang Shi-Fang Zhao Xiang Guo Mei Li Jia-Xi Cui Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China Department of Bioengineering University of PennsylvaniaPhiladelphiaPennsylvania19104USA College of Chemistry and Molecular Engineering Peking UniversityBeijing100871China School of medicine Shaoxing UniversityShaoxing312000China School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610054China

A photo-controlled approach is developed to regulate the interpenetrating polymer network(IPN)topology by varying the connecting structure between the first and second *** approach is based on multifunctional inimer(Vinyl-o NB-Br)possessing three moieties,i.e.,an acrylate-based double bond for incorporation within a polymer network,a Br group for grafting polymerization to get connectIPN(c-IPN),and an o-nitrobenzyl spacer for photocleaving to convert the c-IPN to disconnected-IPN(d-IPN)with UV light *** design allows for finely controlling the connection degree between two networks.A systematic study on the mechanical property of a series of samples with different connection degrees thus can be *** results reveal that decreasing the connecting degree between two networks of IPN made a negligible contribution to materials'mechanical properties.

关键词： Interpenetrating polymer network Network topology o-Nitrobenzyl Inimer Mechanical property

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屏幕阅读与纸上阅读的差异研究探析

乐山师范学院学报 2024年第4期39卷 86-93,123页

作者：谢继红卢雪姚凤珠张海霞天水师范学院教师教育学院甘肃天水741001

屏幕阅读与纸上阅读是两种基于不同信息媒介的阅读形式。根据以往研究发现,个体对屏幕阅读和纸上阅读的态度偏好没有统一的定论,屏幕阅读和纸上阅读的过程差异研究结论也不一致,屏幕阅读的测验成绩低于纸上阅读的测验成绩。两种阅读成... 详细信息

屏幕阅读与纸上阅读是两种基于不同信息媒介的阅读形式。根据以往研究发现,个体对屏幕阅读和纸上阅读的态度偏好没有统一的定论,屏幕阅读和纸上阅读的过程差异研究结论也不一致,屏幕阅读的测验成绩低于纸上阅读的测验成绩。两种阅读成绩差异的原因可以用认知负荷理论、浅层加工假说、认知地图建构模型及媒介的物质特性学理论进行解释。未来需要进一步探讨两种阅读成绩差异的原因;研究两种阅读成绩差异的影响因素;使用探究阅读过程的研究方法,统一测量工具以及开展提升屏幕阅读成绩的应用研究。

关键词：屏幕阅读纸上阅读阅读成绩阅读过程

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昆虫先天免疫调控机制的研究进展

寄生虫与医学昆虫学报 2024年第2期31卷 115-122页

作者：包顺才卢雪侯晓晖遵义医科大学基础医学院细胞生物学教研室贵州遵义563099

在自然环境中,昆虫会和微生物病原体发生广泛的接触。其中,媒介昆虫携带的病毒等病原会导致严重的人类疾病或动物疫病。而昆虫主要通过先天免疫系统来应对病原体的感染。昆虫先天免疫按照其组织和作用方式的不同主要分为细胞和体液免疫... 详细信息

在自然环境中,昆虫会和微生物病原体发生广泛的接触。其中,媒介昆虫携带的病毒等病原会导致严重的人类疾病或动物疫病。而昆虫主要通过先天免疫系统来应对病原体的感染。昆虫先天免疫按照其组织和作用方式的不同主要分为细胞和体液免疫。细胞免疫指由血细胞介导的吞噬、集结和包囊反应。而体液免疫则主要依靠脂肪体细胞所分泌的免疫蛋白,通过抗菌肽或黑化反应来抵御病原体。抗菌肽的激活转录,离不开相应的免疫信号通路的参与,如:Toll、IMD、JAK/STAT等。昆虫先天免疫的研究会促进新方法的开发以保护人类和动物宿主免受媒介传播病原的威胁。

关键词：昆虫免疫先天免疫途径细胞免疫体液免疫黑化反应