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基于三维激光点云的固体火箭发动机喷管零部件尺寸测量方法研究

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固体火箭技术 2024年第2期47卷 278-284页

作者：马智睿朱金薇耿靖源王玉平乔娅婷昝文媛袁玉华陕西电器研究所固体火箭发动机先进检测技术中心西安710025 陕西中天火箭技术股份有限公司西安710025

为实现固体发动机喷管小型零部件尺寸高效、精确的非接触式测量,采用三维激光扫描技术测量喷管的上支耳尺寸,通过点云粗配准和精配准将其正反两面的点云数据精准拼接,在传统的ICP(Iterative Closest Point)迭代最近点的配准方式上结合Oc... 详细信息

为实现固体发动机喷管小型零部件尺寸高效、精确的非接触式测量,采用三维激光扫描技术测量喷管的上支耳尺寸,通过点云粗配准和精配准将其正反两面的点云数据精准拼接,在传统的ICP(Iterative Closest Point)迭代最近点的配准方式上结合Octree算法,优化了搜索过程并排除了异常匹配点对,最后将配准后的点云模型导入Geomagic ControlX中进行测量。结果表明,与三坐标测量值相比较,36只不同上支耳的三维激光扫描精度基本保持在±0.05 mm范围内;测量15次单件上支耳获取测量结果的平均时间4.98 s,重复性小于2%,测量精度和重复性的满足工艺规程和要求。

关键词：喷管小型零部件三维激光扫描尺寸测量点云数据点云配准

Single-molecule imaging of dinitrogen molecule adsorption on individual iron phthalocyanine

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Nano Research 2020年第9期13卷 2393-2398页

作者： Chengding Gu Jia Lin Zhang Jian Qiang Zhong Qian Shen Xiong Zhou Kaidi Yuan Shuo Sun Xu Lian zhirui ma Wei Chen Department of Chemistry National University of SingaporeSingapore 117543Singapore Department of Physics National University of SingaporeSingapore 117542Singapore Department of Interface Science Fritz-Haber-Institut der Max-Planck-GesellschaftBerlin 14195Germany Institute of Advanced materials Nanjing Tech UniversityNanjing 210009China BNLMS College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School of Physical Science and Technology Shanghai Tech UniversityShanghai 200031China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China National University of Singapore(Suzhou)Research Institute Suzhou 215123China

Nitrogen fixation is a vital process for both nature and *** the nitrogenase can reduce nitrogen in ambient environment in nature,the industrialized Haber-Bosch process is a high temperature and high-pressure *** the discovery of the first dinitrogen complex in 1965,many dinitrogen complexes are prepared in a homogeneous solution to mimic the nitrogenase enzyme in ***,studies of the heterogeneous process on surface are rarely ***,molecular scale characterization for such dinitrogen complex is ***,we present a simple model system to investigate,at the single-molecule level,the binding of dinitrogen on a surface confined iron phthalocyanine(FePc)monolayer through the combination of in-situ low-temperature scanning tunneling microscopy(LT-STM)and X-ray photoelectron spectroscopy(XPS)*** iron center in FePc molecule deposited on Au(111)and highly oriented pyrolytic graphite(HOPG)surface can adsorb dinitrogen molecule at room temperature and low pressure.A comparative study reveals that the adsorption behaviors of FePc on these two different substrates are *** bond is formed between the dinitrogen and the Fe atom in the FePc molecule,which greatly modifies the electronic structure of *** bonding is reversible and can be manipulated by applying bias using a STM tip or by thermal annealing.

关键词： single-molecule dinitrogen iron phthalocyanine axial coordination

Pressure-dependent band-bending in ZnO:A near-ambient-pressure X-ray photoelectron spectroscopy study

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Journal of Energy Chemistry 2021年第9期30卷 25-31页

作者： zhirui ma Xu Lian Kaidi Yuan Shuo Sun Chengding Gu Jia Lin Zhang Jing Lyu Jian-Qiang Zhong Lei Liu Hexing Li Wei Chen Department of Physics Hangzhou Normal UniversityHangzhou 310036China Department of Chemistry National University of Singapore3 Science Drive 3117543 Singapore Center for Advanced 2D materials National University of Singapore117546 Singapore School of Physical Science and Technology ShanghaiTech University201210 ShanghaiChina State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsChinese Academy of SciencesNo.3888 Dongnanhu RoadChangchun 130033China Key Laboratory of Resource Chemistry of Ministry of Education College of Chemistry and Materials ScienceShanghai Normal University200234 ShanghaiChina Department of Physics National University of Singapore2 Science Drive 3117542 Singapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

ZnO-based catalysts have been intensively studied because of their extraordinary performance in lower olefin synthesis,methanol synthesis and water-gas shift ***,how ZnO catalyzes these reactions are still not well ***,we investigate the activations of CO_(2),O_(2)and CO on single crystalline ZnO polar surfaces at room temperature,through in-situ near-ambient-pressure X-ray photoelectron spectroscopy(NAP-XPS).It is revealed that O_(2)and CO_(2)can undergo chemisorption on ZnO polar surfaces at elevated *** the ZnO(0001)surface,molecular CO_(2)(O_(2))can chemically interact with the top layer Zn atoms,leading to the formation of CO_(2)^(δ-)(O_(2)^(δ-))or partially dissociative atomic oxygen(O-)and hence the electron depletion layer in ***,an apparent upward band-bending in ZnO(0001)is observed under the CO_(2)and O_(2)*** the ZnO(0001)surface,the molecular chemisorbed CO_(2)(O_(2))mainly bond to the surface oxygen vacancies,which also results in an upward bandbending in ZnO(0001).In contrast,no band-bending is observed for both ZnO polar surfaces upon CO *** electron-acceptor nature of the surface bounded molecules/atoms is responsible for the reversible binding energy shift of Zn 2 p_(3/2)and O 1 s in *** findings can shed light on the fundamental understandings of CO_(2)and O_(2)activation on ZnO surfaces,especially the role of ZnO in heterogeneous catalytic reactions.

关键词： Near-ambient-pressure X-ray photoelectron spectroscopy Zinc oxide Carbon dioxide and oxygen activation Band-bending

An in-situ spectroscopy investigation of alkali metal interaction mechanism with the imide functional group

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Nano Research 2020年第12期13卷 3224-3229页

作者： Xu Lian zhirui ma Zhonghan Zhang Jinlin Yang Shuo Sun Chengding Gu Yuan Liu Honghe Ding Jun Hu Xu Cao Junfa Zhu Shuzhou Li Wei Chen Department of Chemistry National University of SingaporeSingapore117543Singapore Centre for Advanced 2D materials National University of SingaporeSingapore117546Singapore School of materials Science and Engineering Nanyang Technological UniversitySingapore639798Singapore National University of Singapore(Suzhou)Research Institute Suzhou215123China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou350207China National Synchrotron Radiation Laboratory Department of Chemical PhysicsUniversity of Science and Technology of ChinaHefei230029China Department of Physics National University of SingaporeSingapore117542Singapore

Organic anode materials have attracted considerable interest owing to their high tunability by adopting various active functional ***,the interaction mechanisms between the alkali metals and the active functional groups in host materials have been rarely studied ***,a widely used organic semiconductor of perylene-3,4,9,10-tetracarboxylic diimide(PTCDI)was selected as a model system to investigate how alkali metals interact with imide functional groups and induce changes in chemical and electronic structures of *** interaction at the alkali/PTCDI interface was probed by in-situ X-ray photoelectron spectroscopy(XPS),ultraviolet photoelectron spectroscopy(UPS),synchrotron-based near edge X-ray absorption fine structure(NEXAFS),and corroborated by density functional theory(DFT)*** results indicate that the alkali metal replaces the hydrogen atoms in the imide group and interact with the imide nitrogen of *** transfer induced gap states and downward band-bending like effects are identified on the alkali-deposited PTCDI *** was found that Na shows a stronger electron transfer effect than *** a model study of alkali insertion/intercalation in PTCDI gives insights for the exploration of the potential host materials for alkali storage applications.

关键词： perylene-3,4,9,10-tetracarboxylic diimide(PTCDI) lithium storage organic anode imide electron transfer

利用SCGE技术对植物盐胁迫下DNA损伤的研究

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衡水学院学报 2024年第1期26卷 22-26页

作者：郭晓丽刘芯瑜刘思萌马志蕊左亮罗博张旭衡水学院生命科学学院河北衡水053000

以北斗七星蚕豆为试验材料,分别采用0,6,12,18,24,30g/L的6个质量浓度的NaCl溶液处理蚕豆根尖,利用SCGE技术对蚕豆根尖细胞在不同质量浓度盐胁迫下DNA的损伤进行检测,探讨逆境胁迫对植物细胞DNA的损伤效应,并以此建立快速准确的植物DNA... 详细信息

以北斗七星蚕豆为试验材料,分别采用0,6,12,18,24,30g/L的6个质量浓度的NaCl溶液处理蚕豆根尖,利用SCGE技术对蚕豆根尖细胞在不同质量浓度盐胁迫下DNA的损伤进行检测,探讨逆境胁迫对植物细胞DNA的损伤效应,并以此建立快速准确的植物DNA损伤检测流程。结果表明,盐胁迫会对蚕豆根尖细胞DNA造成损伤,并且随着盐胁迫质量浓度的升高,细胞拖尾加剧,30 g/L盐胁迫下的细胞拖尾最明显;此外,当NaCl溶液质量浓度大于18 g/L时,随着NaCl溶液质量浓度的增加,蚕豆根尖细胞拖尾率逐渐增大,根尖细胞损伤概率增加。通过利用多种比较分析细胞尾部DNA发现,随着盐胁迫质量浓度的增加,细胞的彗星尾长增加显著,同时利用软件分析可增加对DNA损伤的直观检测,具有较好的应用效果。最后,通过对实验过程中涂层琼脂糖溶液和包埋凝胶溶液的制备、载玻片涂胶处理方法等均进行了合理的改良,为后续大批量开展植物逆境胁迫条件的评估提供便利。

关键词： SCGE 盐胁迫根尖细胞 DNA损伤

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V型调节球阀阀盖内壁气-固冲蚀的数值模拟

科学技术创新 2024年第9期 221-224页

作者：马志锐李福宝霍英妲王张勇狄军涛吴恒王悦沈阳工业大学化工装备学院辽宁辽阳上海纽京阀门有限公司上海

调节球阀工作时,其阀盖内壁处容易受到介质冲蚀而被穿透,结合阀盖内流场特征与阀盖受损情况,采用数值模拟的方法研究这一冲蚀过程。在流场模拟基础上,又进一步探究了阀球旋转角度分别取30°、50°、70°情况下阀盖内壁的冲蚀磨损情况,借... 详细信息

调节球阀工作时,其阀盖内壁处容易受到介质冲蚀而被穿透,结合阀盖内流场特征与阀盖受损情况,采用数值模拟的方法研究这一冲蚀过程。在流场模拟基础上,又进一步探究了阀球旋转角度分别取30°、50°、70°情况下阀盖内壁的冲蚀磨损情况,借助Fluent对阀盖壁面冲蚀磨损状况进行仿真分析。最后,通过改变阀座入口处的通道宽度来计算模拟出最佳的通道尺寸,并且对阀盖内壁进行加固处理,使得阀壁处受介质冲蚀影响最小。

关键词： V型调节球阀冲蚀磨损数值模拟气固两相流仿真分析

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双层透孔-平纹角链锁立体机织物的开发

上海纺织科技 2017年第2期45卷 31-33页

作者：马智瑞汉中出入境检验检疫局陕西汉中723000

以555.6 dtex的涤纶长丝为原料,设计开发以双层透孔-平纹组织为基础的角链锁立体机织物。织物外观呈现三层角链锁立体结构,表层六枚透孔组织透孔均匀、平整,底层平纹组织结构紧密、挺括,中层六枚透孔组织分别与上下两层进行接结。此类... 详细信息

以555.6 dtex的涤纶长丝为原料,设计开发以双层透孔-平纹组织为基础的角链锁立体机织物。织物外观呈现三层角链锁立体结构,表层六枚透孔组织透孔均匀、平整,底层平纹组织结构紧密、挺括,中层六枚透孔组织分别与上下两层进行接结。此类织物用于生产帐篷基布,具有优良的物理机械性能,且可以在红外保暖与红外隐身方面取得良好效果。试验结果认为,双层透孔-平纹角链锁立体机织物可以在传统织机与剑杆织机上批量生产,具有一定的经济效益与实际应用价值。

关键词：平纹组织双层织物涤纶六枚透孔组织角链锁

广义SBM模型及其在医疗机构效率分析中的应用

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内蒙古大学学报（自然科学版） 2023年第5期54卷 537-547页

作者：曹莉马智瑞马占新吴悦欣内蒙古医科大学计算机信息学院呼和浩特010110 山西医科大学公共卫生学院太原030001 内蒙古大学经济管理学院呼和浩特010021

SBM模型是一种重要的DEA模型,由于其考虑到了各指标的松弛量,因此,在实践中得到广泛应用。然而,该方法也存在不足之处:(1)原有的DEA生产可能集由所有决策单元构成,但实际上决策单元的参考集可能包含更多的形式。(2)对决策单元的数据按... 详细信息

SBM模型是一种重要的DEA模型,由于其考虑到了各指标的松弛量,因此,在实践中得到广泛应用。然而,该方法也存在不足之处:(1)原有的DEA生产可能集由所有决策单元构成,但实际上决策单元的参考集可能包含更多的形式。(2)对决策单元的数据按年度分组计算DEA效率的方法可能缺乏传递性。(3)SBM模型无法测算残缺的面板数据。为了解决这些问题,本文提出了可以依据多种生产前沿面,对带有非期望产出的非平衡面板数据进行评价的基于广义参考集的SBM模型,并应用该模型分析了内蒙古地区三甲医院的效率状况。

关键词：多目标决策综合评价数据包络分析 SBM模型医疗机构

低温冷冻对桑蚕丝纤维表面结构和染色性能的影响

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丝绸 2014年第1期51卷 20-25页

作者：蓝海啸马智瑞庞互强汉中出入境检验检疫局陕西汉中723000

针对桑蚕丝纤维进行低温冷冻处理,利用扫描电镜和原子力显微镜对冷冻前后纤维表面结构的变化进行表征;采用活性染料兰纳素蓝3G对桑蚕丝纤维进行染色,测试了不同冷冻条件下桑蚕丝纤维的上染率、固着率和总固着率,分析了冷冻处理对桑蚕丝... 详细信息

针对桑蚕丝纤维进行低温冷冻处理,利用扫描电镜和原子力显微镜对冷冻前后纤维表面结构的变化进行表征;采用活性染料兰纳素蓝3G对桑蚕丝纤维进行染色,测试了不同冷冻条件下桑蚕丝纤维的上染率、固着率和总固着率,分析了冷冻处理对桑蚕丝纤维表面结构和染色性能的影响。试验结果表明:经过低温冷冻处理后,桑蚕丝纤维表面结构发生变化,桑蚕丝纤维的染色性能得到改善,在回潮率40%,温度-86℃,冷冻时间48 h的冷冻处理条件下,桑蚕丝纤维上染率、固着率和总固着率分别提高27%、14%和35.3%。

关键词：低温冷冻桑蚕丝表面结构染色性能