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中国激光 1993年第10期20卷 725-728页

作者：柴燕杰张汉一谢世钟孙波周炳琨清华大学电子工程系北京100084

本文分析了强反馈外腔半导体激光器的宽带频率调谐特性,得到了最大频率调谐范围公式,利用1.5μm外腔半导体激光器实现了1.45μm至1.57μm范围内的波长宽带调谐(120nm调谐范围)。

关键词：可调谐激光器半导体激光器激光器

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船舶移动式柴油应急消防泵性能与应用

机电设备 2023年第4期40卷 22-25页

作者：马东芝周林强谢彦杰武警海警学院机电管理系浙江宁波315801 92569部队海南三亚572000 中国海警局直属第五局海南三亚572000

介绍船舶某型便携式移动式柴油应急消防泵基本结构和工作原理,结合试验数据对其性能进行分析,阐述该型移动式柴油应急消防泵的标准启动流程,并针对使用过程中出现的问题提出使用注意事项,有效减少该型设备的故障发生率并延长应急消防泵... 详细信息

介绍船舶某型便携式移动式柴油应急消防泵基本结构和工作原理,结合试验数据对其性能进行分析,阐述该型移动式柴油应急消防泵的标准启动流程,并针对使用过程中出现的问题提出使用注意事项,有效减少该型设备的故障发生率并延长应急消防泵的使用周期。

关键词：船舶移动式柴油机应急消防泵

基于平均法的余弦激励分数阶振子系统动力学分析

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工程数学学报 2024年第4期41卷 623-641页

作者：师玮郭蓉解加全张彦杰王涛黄庆学太原理工大学机械与运载工程学院太原030024 金属成形技术与重型装备全国重点实验室太原030024 先进金属复合材料成形技术与装备教育部工程研究中心太原030024 中北大学理学院太原030051

提出了一种求解余弦激励下分数阶振子系统位移响应的解析和数值算法。其中解析方法是用平均法来求出系统的稳态响应解和瞬态响应解,总位移响应解即为稳态解和瞬态解的总和。提出一种数值方法,利用Grunwald-Letnikov分数阶导数的定义将... 详细信息

提出了一种求解余弦激励下分数阶振子系统位移响应的解析和数值算法。其中解析方法是用平均法来求出系统的稳态响应解和瞬态响应解,总位移响应解即为稳态解和瞬态解的总和。提出一种数值方法,利用Grunwald-Letnikov分数阶导数的定义将系统中的分数阶微分项进行离散化处理,降低了原系统阶数。在一般的周期激励下,系统的近似响应解可以采用傅里叶级数展开法和线性系统叠加原理得到。最后,利用数值模拟对所提方法的有效性和可行性进行了验证,并对分数阶阶次、线性阻尼系数和分数阶导数系数对系统稳态响应振幅和总位移响应的影响进行了分析。

关键词：平均法分数阶振子系统 Grunwald-Letnikov分数阶导数位移响应

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坡度X70管线钢全自动外焊接头组织与性能

中国石油大学学报（自然科学版） 2024年第3期48卷 145-153页

作者：韩彬高建章周聪贾彦杰刘雪光谢斐牛盛源李立英中国石油大学(华东)材料科学与工程学院山东青岛266580 国家管网集团西南管道有限责任公司四川成都610095 海洋石油工程股份有限公司天津300461

采用全自动外焊工艺对坡度为25°的X70管线钢进行焊接,利用光学显微镜和背散射电子衍射(EBSD)对焊接接头组织进行观察,并对焊接接头进行拉伸、弯曲、硬度、冲击和裂纹尖端张开位移(CTOD)等试验。结果表明:上下坡口的粗晶区宽度和焊接残... 详细信息

采用全自动外焊工艺对坡度为25°的X70管线钢进行焊接,利用光学显微镜和背散射电子衍射(EBSD)对焊接接头组织进行观察,并对焊接接头进行拉伸、弯曲、硬度、冲击和裂纹尖端张开位移(CTOD)等试验。结果表明:上下坡口的粗晶区宽度和焊接残余应力不同,上坡口粗晶区宽、残余应力大;焊接位置明显影响内表面熔合线冲击功,平焊和立焊位置内表面熔合线冲击功远低于仰焊位置,是接头的韧性薄弱区;焊缝冲击功较高而CTOD值较低,建议评定焊接接头韧性应同时考虑冲击功和CTOD值;根焊区是焊接接头的危险区,易引起环焊缝失效,建议采用等强或高强匹配,焊接工艺评定应区分山区和平原地区,对山区条件下接头进行焊接工艺评定时一定要重点关注根焊区。

关键词：大坡度 X70管线钢全自动焊显微组织韧性

维普期刊数据库博看期刊

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南宁市红棕象甲发生情况初步调查及防治对策

热带林业 2009年第2期37卷 40-41,31页

作者：覃连红欧善生谢彦洁王小欣申晓萍广西农业职业技术学院广西南宁530007

文章简要描述了红棕象甲的形态特征及为害特点,通过调查得到,红棕象甲在南宁市的寄主有大王椰子等7个树种。在各发生点中,苗圃的寄主植物种类较多,受害严重;行道、公园等则寄主种类少,受害较轻。最后,文章就调查结果进行了讨论,并对该... 详细信息

文章简要描述了红棕象甲的形态特征及为害特点,通过调查得到,红棕象甲在南宁市的寄主有大王椰子等7个树种。在各发生点中,苗圃的寄主植物种类较多,受害严重;行道、公园等则寄主种类少,受害较轻。最后,文章就调查结果进行了讨论,并对该虫提出了植物检疫、日常管理等三方面的防治措施。

关键词：红棕象甲棕榈科植物检疫

低体质量新生儿血浆氨基酸代谢谱和肠道菌群与临床结局的关系

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中国微生态学杂志 2024年第4期36卷 457-461页

作者：李延峰张杨帆孙雪韩彦洁王献伟谢佳良石家庄市人民医院输血科河北050000 石家庄市人民医院检验科河北050000 石家庄市第四医院输血科

目的探究低体质量新生儿血浆氨基酸代谢谱和肠道菌群变化及其与临床结局的关系,为该类患儿的治疗提供参考。方法选取2015年1月至2022年12月石家庄市第四医院收治的150例低体质量新生儿作为研究对象,根据临床结局分为结局良好组(117例... 详细信息

目的探究低体质量新生儿血浆氨基酸代谢谱和肠道菌群变化及其与临床结局的关系,为该类患儿的治疗提供参考。方法选取2015年1月至2022年12月石家庄市第四医院收治的150例低体质量新生儿作为研究对象,根据临床结局分为结局良好组(117例)与结局不良组(33例),比较两组患儿血浆氨基酸水平和肠道菌群数量。结果结局不良组患儿死亡3例、败血症5例、贫血5例、支气管肺发育不良9例、视网膜病变6例、先天性心脏病3例、高胆红素血症1例、呼吸窘迫综合征1例。结局不良组患儿出生体质量[(1368.56±150.73)g]低于结局良好组[(1563.78±184.95)g],差异有统计学意义(t=5.561,P<0.05)。结局不良组患儿血浆精氨酸、瓜氨酸、半胱氨酸、苏氨酸水平均高于结局良好组(均P<0.05),而天冬氨酸、谷氨酸、甘氨酸、亮氨酸、缬氨酸水平均低于结局良好组(均P<0.05)。结局不良组新生儿粪便中双歧杆菌、乳杆菌数量均低于结局良好组(均P<0.05)。结论低体质量新生儿血浆氨基酸代谢水平和肠道菌群与临床不良结局有一定的关系。

关键词：低体质量新生儿氨基酸代谢肠道菌群临床结局

A micro-scale strain rosette for residual stress measurement by SEM Moiré method

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Science China(Physics,Mechanics & Astronomy) 2014年第4期57卷 716-722页

作者： ZHU RongHua xie HuiMin ZHU JianGuo LI yanjie CHE ZhiGang ZOU ShiKun Key Laboratory of Applied Mechanics (AML) Department of Engineering Mechanics Tsinghua University School of Civil Engineering and Architecture University of Jinan Beijing Aeronautical Manufacturing Technology Research Institute

In this paper,a new method combining focused ion beam(FIB)and scanning electron microscope(SEM)Moirétechnique for the measurement of residual stress at micro scale is *** FIB is employed to introduce stress relief like the macro ring-core method and fabricate gratings with a frequency of 5000 lines/mm on the measured area of the sample *** groups of gratings in different radial directions are manufactured in order to form a micro-scale strain *** milling ring-core by FIB,the deformation incurred by relief of the stress will be recorded with the strain *** displacement/strain field can be measured using SEM scanning Moiréwith random phase-shifting *** this study,the Nickel alloy GH4169 sample(which was processed by laser shock peening)is selected as a study object to determine its residual *** results showed that the components of the in-plane principal stresses were-359 MPa and-207 MPa,respectively,which show good agreement with the results obtained from the available literature.

关键词： residual stress focused ion beam SEM Moiré method ring-core method random phase-shifting

The Residual Strain Measurement of Thin Conductive Metal Wire after Electrical Failure with SEM Moir

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Acta Mechanica Solida Sinica 2016年第4期29卷 371-378页

作者： yanjie Li Huimin xie Qinghua Wang Mengmeng Zhou Manqiong Xu Qiang Luo Changzhi Gu AML Department of Engineering Mechanics Tsinghua University School of Civil Engineering and Architecture University of Jinan National Institute of Advanced Industrial Science and Technology Institute of Physics Chinese Academy of Sciences

In this study, the residual strain of a thin conductive metal wire on a polymer substrate after electrical failure is measured with SEM moir′e. Focused ion beam(FIB) milling is applied to fabricate micron moir′e gratings on the surfaces of constantan wires and the random phase shifting technique is used to process moir′e fringes. The virtual strain method is briefly introduced and used to calculate the real strain of specimens. In order to study the influence of a defect on the electrical failure of the constantan wire, experiments were conducted on two specimens, one with a crack, while the other one without any crack. By comparing the results, we found that the defect makes the critical beam current of electrical failure decrease. In addition, the specimens were subjected to compression after electrical failure, in agreement with the observed crack closure of the specimen. The successful results demonstrate that the moir′e method is effective to characterize the full-field deformation of constantan wires on the polymer membrane, and has a good potential for further application to the deformation measurement of thin films.

关键词： SEM moir′e residual strain metal wire focused ion beam(FIB)

Coronas around Olivine in the Miaowan Olivine Norite, Yangtze Craton, South China

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Journal of Earth Science 2019年第5期30卷 924-937页

作者： Shuhua Fan Zhaochong Zhang Changqian Ma Qiuhong xie Lianxun Wang yanjie Li Yuzhe Zhang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China College of Desert Control Science and Engineering Inner Mongolia Agricultural University Hohhot 010018 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China School of Earth Sciences Lanzhou University Lanzhou 730000 China

Coronitic microstructures have been used to interpret the late-stage solidification history of igneous rocks and to constrain the corresponding chemical and/or physical changes. Coronas with three shells were also recognized in the Miaowan olivine norite, Yangtze Craton, South China. In our study, orthopyroxene intergrowth with vermicular magnetite in the inner shell is in optical continuity with magnetite-free orthopyroxene in the middle shell. In the outer shell of brown amphibole remaining magnetite-free orthopyroxene inclusions sporadically occur. Meanwhile Mg# values of orthopyroxene(76–80) in the inner and middle shells are basically consistent with olivine(78–81). In this paper, we propose a multi-stage genetic model for the formation of coronas in the Miaowan olivine norite. In the first stage, the magnetite-free orthopyroxene shell formed through reaction between primocrystal olivine with the residual Si-rich melt at 990–1 053 ℃ and 6.2–6.5 kbar. In the second stage, the orthopyroxene-magnetite symplectite shell formed when primocrystal olivine reacted with the late-stage residual Fe-rich melt promoted by high oxygen fugacity condition at 927–1 035 ℃ and 6.0–6.5 kbar. In the third stage, the brown amphibole shell formed as the presence of residual hydrous melt and replaced the middle shell at 821–900 ℃ and 5.5–6.0 kbar.

关键词： Yangtze Craton Miaowan olivine norite coronas orthopyroxene-magnetite symplectite magmatic origin

A novel random phase-shifting digital holographic microscopy method

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Science China(Technological Sciences) 2009年第7期52卷 2048-2053页

作者： HuiMin xie ZhenXing Hu FuLong Dai yanjie Li PengWan Chen QingMing Zhang FengLei Huang Applied Mechanics Laboratory (AML) Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing 100084 China State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China

This paper proposes a new method that reconstructs the information of specimen by using random phase shift step in digital holographic microscopy (DHM). The principles of the method are described and discussed in detail. In practical experiment, because the phase shifter is neither perfectly linear nor calibrated, digital holograms with inaccurate phase shift step are recorded by the charge-coupled device (CCD). The phase could be accurately reconstructed from the recorded digital holograms by using the random phase-shifting algorithm, which makes up for reconstructed phase error caused by ordinary phase-shifting algorithm. The phase aberration compensation is also discussed. In order to verify the flexibility of the proposed method, numerical simulation of random phase-shifting DHM was carried out. The simulation results illustrated that the presented method is effective when the phase shift step is unknown or random in DHM.

关键词： digital holographic microscopy phase-shifting aberration compensation