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Sodium dodecyl sulfate (SDS) as an effective corrosion inhibitor for Mg-8Li-3Al alloy in aqueous NaCl: A combined experimental and theoretical investigation

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Journal of Magnesium and Alloys 2023年第1期11卷 287-300页

作者： Honggun Song Zhidong Xu Lahouari Benabou Zheng Yin hongyu guan Hong Yan Luo Chao Zhi Hu Xudong Wang Department of Mechanical and Electrical Engineering Nanchang UniversityNanchang330031China UniversitéParis-Saclay UVSQLISV78124Vélizy-VillacoublayFrance Institute for Advanced Study Nanchang UniversityNanchang330031China

The corrosion inhibition behavior of Mg-8Li-3Al alloy in NaCl solution with sodium dodecyl sulfate(SDS)was investigated by hydrogen analysis,scanning electron microscopy(SEM),electrochemical test,scanning Kelvin probe force microscopy(SKPFM)and computational *** showed that the corrosion resistance of Mg-8Li-3Al alloy in NaCl solution was effectively improved with *** SEM and SKPFM results confirmed a dense,200 nm-thick SDS-adsorbed layer had formed on the alloy *** separation energy ΔE_(gap) and adsorption energy E_(ads) of SDS on the Mg surface were calculated by density functional theory and molecular dynamics simulations,*** the corrosion inhibition mechanism was hypothesized and described.

关键词： Mg-Li alloy Corrosion Sodium dodecyl sulfate Scanning kelvin probe force microscopy Density functional theory Molecular dynamics

Electrospinning preparation and characterization of polyoxometalate fibers

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Chinese Science Bulletin 2006年第8期51卷 906-910页

作者： YU Hongquan PENG Jun guan hongyu XIN Zhifeng PAN Yan GONG Jian SHAO Changlu DONG Baoxia Faculty of Chemistry Northeast Normal University Changchun 130024 China Faculty of Physics Northeast Normal University Changchun 130024 China

Poly(vinyl alcohol)/K7[SiW11O39Co(H3P2- O7)] hybrid fine fiber mats (PVA/SiW11Co-P2O7) were prepared through electrospinning technique. After calcinations of PVA/SiW11Co-P2O7 at 500℃ for 8 h, pure SiW11Co-P2O7 fine fibers were obtained with the Keggin structure keeping unchanged. The fiber mats were characterized by IR, ESR, PXRD and scanning electron microscopy (SEM) methods. The average diameter of the fibers is about 250 nm. The SiW11Co- P2O7 fibers showed color change when absorbing and desorbing moisture.

关键词：乳酸光纤电子自旋 PVA SiW11Co-P2O7 制备 SEM 乙烯醇

Molecular cloning and functional identification of sterol C24-methyltransferase gene from Tripterygium wilfordii

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Acta Pharmaceutica Sinica B 2017年第5期7卷 603-609页

作者： hongyu guan Yujun Zhao Ping Su Yuru Tong Yujia Liu Tianyuan Hu Yifeng Zhang Xianan Zhang Jia Li Xiaoyi Wu Luqi Huang Wei Gao School of Traditional Chinese Medicine Capital Medical University State Key Laboratory Breeding Base of Dao-di Herbs National Resource Center for Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing University of Chinese Medicine Third Affiliated Hospital

Sterol C24-methyltransferase(SMT) plays multiple important roles in plant growth and development. SMT1, which belongs to the family of transferases and transforms cycloartenol into 24-methylene cycloartenol, is involved in the biosynthesis of 24-methyl sterols. Here, we report the cloning and characterization of a cDNA encoding a sterol C24-methyltransferase from Tripterygium wilfordii(Tw SMT1). Tw SMT1(Gen Bank access number KU885950) is a 1530 bp cDNA with a 1041 bp open reading frame predicted to encode a 346-amino acid, 38.62 k Da protein. The polypeptide encoded by the SMT1 cDNA was expressed and purified as a recombinant protein from Escherichia coli(E. coli) and showed SMT activity. The expression of Tw SMT1 was highly up-regulated in T. wilfordii cell suspension cultures treated with methyl jasmonate(Me JA). Tissue expression pattern analysis showed higher expression in the phellem layer compared to the other four organs(leaf, stem, xylem and phloem), which is about ten times that of the lowest expression in leaf. The results are meaningful for the study of sterolbiosynthesis of T. wilfordii and will further lay the foundations for the research in regulating both the content of other main compounds and growth and development of T. wilfordii.

关键词： Cloning Cycloartenol C24-methyl transferase Enzymatic assay Inducible expression Tissue expression

On the technologies of Hα imaging spectrograph for the CHASE mission

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Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 29-36页

作者： Qiang Liu Hongjiang Tao Changzheng Chen Chengshan Han Zhe Chen Gui Mei Liang Yang Qinglong Hu Hongwei Xin Xiansheng Li hongyu guan Donglin Xue Mingchao Zhu Changhong Hu Qinghua Ha Yukun He Cheng Fang Chuan Li Zhen Li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory for Modern Astronomy and Astrophysics Ministry of EducationNanjing 210023China

The Hα imaging spectrograph(HIS) is the scientific payload of the first solar space mission, the Chinese Hα solar explorer(CHASE), supported by the China National Space Administration(CNSA). The CHASE/HIS achieves, for the first time in space, Hα spectroscopic observations with high spectral and temporal resolutions. Separate channels for the raster scanning mode(RSM) and continuum imaging mode(CIM) are integrated into one, and a highly integrated design is achieved through multiple folding of the optical path and ultra-light miniaturized components. The design of HIS implements a number of key technologies such as high-precision scanning of the optical field of view(FOV), high-precision integrated manufacturing inspection, a large-tolerance pre-filter window, and full-link solar radiation calibration. The HIS instrument has a pixel spectral resolution of 0.024 ? and can complete a full-Sun scanning within 46 s.

关键词： space-based telescope design and performance testing of optical systems scan imaging

Graphene-enabled electrically controlled terahertz meta-lens

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Photonics Research 2018年第7期6卷 703-708页

作者： WEIguanG LIU BIN HU ZONGDUO HUANG hongyu guan HETING LI XINKE WANG YAN ZHANG HONGXING YIN XIAOLU XIONG JUAN LIU YONGTIAN WANG Beijing Engineering Research Center for Mixed Reality and Advanced Display School of Optics and Photonics Beijing Institute of Technology Beijing Key Laboratory for Metamaterials and Devices Key Laboratory of Terahertz Optoelectronics Ministry of Educationand Beijing Advanced Innovation Center for Imaging Technology Department of Physics Capital Normal University Micro and Nanotechnology Research Center School of Physics Beijing Institute of Technology

Metasurfaces have become a new photonic structure for providing potential applications to develop integrated devices with small thickness, because they can introduce an abrupt phase change by arrays of scatterers. To be applied more widely, active metasurface devices are highly desired. Here, a tunable terahertz meta-lens whose focal length is able to be electrically tuned by ～4.45λ is demonstrated experimentally. The lens consists of a metallic metasurface and a monolayer graphene. Due to the dependence of the abrupt phase change of the metasurface on the graphene chemical potential, which can be modulated using an applied gate voltage, the focal length is changed from 10.46 to 12.24 mm when the gate voltage increases from 0 to 2.0 V. Experimental results are in good agreement with the theoretical hypothesis. This type of electrically controlled meta-lens could widen the application of terahertz technology.

关键词：散射体阵列光子结构通讯技术发展现状

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高分六号卫星甚宽视场相机的热控设计及验证

红外与激光工程 2023年第11期52卷 310-312,313-319页

作者：于善猛江帆杜春平王航关洪宇关奉伟刘巨王灵杰中国科学院长春光学精密机械与物理研究所吉林长春130033

甚宽视场相机作为高分六号卫星的核心载荷,具备65.6°视场、862 km超大幅宽和8谱段成像能力。针对其自由曲面离轴四反光学系统的结构特点和任务需求,采用复合型多层隔热组件进行热隔离、高导热率石墨膜进行热疏导及分级热控等措施进行... 详细信息

甚宽视场相机作为高分六号卫星的核心载荷,具备65.6°视场、862 km超大幅宽和8谱段成像能力。针对其自由曲面离轴四反光学系统的结构特点和任务需求,采用复合型多层隔热组件进行热隔离、高导热率石墨膜进行热疏导及分级热控等措施进行了热控设计,实现了光机结构的精密控温和高热耗/热流密度电子学设备的高效散热,并利用有限元分析软件UG12.0/Space thermal仿真分析了相机高、低温工况下的温度;通过对比热分析、热试验及卫星在轨遥测温度数据,验证了该热控方案的实际效果。在轨遥测数据显示:光机结构在轨温度水平为19.7~20.3℃,温度梯度最大不超过0.4℃,CMOS焦面组件每轨摄像12 min的情况下,温度波动在19~24℃,均满足热控指标要求,遥测数据与热分析及热试验结果偏差小于±0.5℃。表明该相机热设计正确可行,热分析及热试验过程合理可靠。

关键词：热控设计甚宽视场相机热平衡试验在轨验证

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SRGM中TE建模机制与模型比较分析

哈尔滨工业大学学报 2015年第5期47卷 32-39页

作者：张策孟凡超崔刚刘宏伟官红玉哈尔滨工业大学计算机科学与技术学院哈尔滨150001 哈尔滨工业大学(威海)计算机科学与技术学院山东威海264209

针对当前与软件可靠性增长模型SRGM(software reliability growth model)紧密相关的测试工作量TE(testing effort)的研究现状,以及全面评价测试工作量函数TEFs(testing effort function)性能的需要,对SRGM下TE相关的建模与模型比较问题... 详细信息

针对当前与软件可靠性增长模型SRGM(software reliability growth model)紧密相关的测试工作量TE(testing effort)的研究现状,以及全面评价测试工作量函数TEFs(testing effort function)性能的需要,对SRGM下TE相关的建模与模型比较问题进行深入研究.分析了近40年的TE发展历程与内容演变,对其与测试成本间关联进行剖析;对典型的TEFs进行了全面梳理与述评;研究了考虑TE的SRGM建模过程;针对8个典型的TEFs,在已发表的4组数据集上进行了深入的性能比较与评述.研究结果表明,有效的TEF可为基于SRGM的可靠性相关研究提供重要决策支持,对考虑TE的SRGM进行综合评价是后续研究的关键.

关键词：软件可靠性测试工作量测试工作量函数软件可靠性增长模型成本

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西部农村学校同伴效应对青少年近视的影响

西北农林科技大学学报（社会科学版） 2022年第1期22卷 77-87页

作者：杜康黄珏瑢关宏宇史耀疆陕西师范大学教育实验经济研究所西安710062 中国农业大学经济管理学院北京100083

我国青少年近视率居高不下,农村地区也不例外,已严重威胁我国未来人力资本水平。基于2018-2019年在西部2省9县农村地区163所学校四至九年级的实地调查数据,使用工具变量法分析了同伴效应对青少年近视的影响。研究发现班级中近视同伴比... 详细信息

我国青少年近视率居高不下,农村地区也不例外,已严重威胁我国未来人力资本水平。基于2018-2019年在西部2省9县农村地区163所学校四至九年级的实地调查数据,使用工具变量法分析了同伴效应对青少年近视的影响。研究发现班级中近视同伴比例越高,青少年的视力水平更差、近视的可能性更大。同时发现同伴效应在近视的青少年中影响更大,但该影响在戴眼镜的近视青少年中有所降低。同伴效应对女生、初中生以及住校生的视力影响更大。作用机制检验发现,同伴近视并未通过间接影响个体对于近视的态度来增大近视可能性,可能主要通过直接改变个体用眼行为产生影响。因为同伴效应的存在,近视防控亟需引起全社会的重视,让近视防控产生社会乘数效应。同时,近视防控工作需要针对不同的青少年给予差异化的关怀与帮助,积极倡导正确的用眼行为。

关键词：同伴效应近视防控青少年近视西部农村学校

无外加溶剂条件下二甲氨基硫代甲酰氯对亚砜的脱氧还原

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有机化学 2021年第8期41卷 3330-3334页

作者：王兴越许昌林关宏宇林觅黄鹏辽宁大学化学院沈阳110036 中国石油化工股份有限公司大连(抚顺)石油化工研究院辽宁大连116045

报道一种简便高效地将亚砜脱氧还原的方法.在100℃条件下,无需外加溶剂,一系列脂肪和芳香亚砜可与二甲氨基硫代甲酰氯反应,以中等到优异的产率生成相应的产物硫醚.该反应可以兼容多种官能团,并且适合克级规模合成.反应可能经过硫代亚砜... 详细信息

报道一种简便高效地将亚砜脱氧还原的方法.在100℃条件下,无需外加溶剂,一系列脂肪和芳香亚砜可与二甲氨基硫代甲酰氯反应,以中等到优异的产率生成相应的产物硫醚.该反应可以兼容多种官能团,并且适合克级规模合成.反应可能经过硫代亚砜中间体的生成和分解成硫醚和硫单质的过程.

关键词：亚砜硫醚脱氧还原硫代