检索结果-南通市图书馆

Journal of Harbin Institute of Technology(New Series) 2017年第6期24卷 45-51页

作者： Tie Gang yilin luan Chi Zhang State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology School of Materials Science and Engineering Heilongjiang University of Science and Technology

A feature extraction method was proposed to sectorial scan image of Ti-6Al-4V electron beam welding seam based on principal component analysis to solve problem of high-dimensional data resulting in timeconsuming in defect recognition. Seven features were extracted from the image and represented 87. 3% information of the original data. Both the extracted features and the original data were used to train support vector machine model to assess the feature extraction performance in two aspects: recognition accuracy and training time. The results show that using the extracted features the recognition accuracy of pore,crack,lack of fusion and lack of penetration are 93%,90.7%,94.7% and 89.3%,respectively,which is slightly higher than those using the original data. The training time of the models using the extracted features is extremely reduced comparing with those using the original data.

关键词： electron beam welding phased array ultrasonic sectorial scan image feature extraction principal component analysis

Interaction of fatigue crack with vibration and ultrasound in metallic rod and its use for quantitative characterization

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Chinese Journal of Acoustics 2016年第2期35卷 155-166页

作者： LIU Bin GANG Tie WAN Chuhao LUO Zhiwei luan yilin State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology School of Materials Science and Engineering Heilongjiang University of Science and Technology

According to the principle of synchronous demodulation, the modulation informa- tion in the output signal of vibro-acoustic modulation test was investigated and the nonlinear interaction of sound and vibration with the crack interface in a metallic rod was analyzed. A swept signal excitation was used to obtain a proper high frequency parameter in the test of alu- minum rod samples with different sizes of cracks and the modulation information in the output signal was analyzed. It was found that the ultrasound wave in the structure can be separated into two parts. One is the wave which passes through the crack interface modulated by the low frequency vibration, and other wave has no any changes. The nonlinear modulation model was modified and a quantitative method for crack detection was proposed. It is demonstrated by comparing with the ultrasonic C-scanning that this method can be used to estimate the fatigue crack size in the metallic rod.

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TiAl/40Cr扩散焊界面质量的超声评价

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焊接学报 2007年第5期28卷 69-72页

作者：栾亦琳刚铁哈尔滨工业大学现代焊接生产技术国家重点实验室哈尔滨150001

采用超声C扫描法对TiAl和40Cr扩散焊界面进行了检测,分别研究了界面回波幅度平均值和标准差与接头抗剪强度之间的关系,并讨论了焊接温度和试样表面粗糙度对上述关系的影响及界面气隙长度与回波幅度的关系。结果表明,当试样表面粗糙度一... 详细信息

采用超声C扫描法对TiAl和40Cr扩散焊界面进行了检测,分别研究了界面回波幅度平均值和标准差与接头抗剪强度之间的关系,并讨论了焊接温度和试样表面粗糙度对上述关系的影响及界面气隙长度与回波幅度的关系。结果表明,当试样表面粗糙度一致时,回波幅度平均值和标准差随着抗剪强度的降低而增加。表面粗糙度会影响回波幅度平均值和标准差与接头抗剪强度的关系。当空气间隙的长度小于400μm时,回波幅度与空气间隙长度近似成正比例关系。

关键词：超声波检测 C扫描扩散焊接异种材料

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搅拌摩擦焊接头抗拉强度无损表征

焊接学报 2009年第6期30卷 1-4页

作者：刚铁赵雪梅林三宝栾亦琳哈尔滨工业大学现代焊接生产技术国家重点实验室哈尔滨150001

材料的弹性模量、显微结构及相应的力学性能可用超声学来表征.对力学性能起决定性作用的显微结构与超声衰减有明显的相关性.采用接收到的斜入射透射波能量变化来表征超声波在搅拌摩擦焊接头(FSW)不同组织中的衰减,从超声C扫描图像中提... 详细信息

材料的弹性模量、显微结构及相应的力学性能可用超声学来表征.对力学性能起决定性作用的显微结构与超声衰减有明显的相关性.采用接收到的斜入射透射波能量变化来表征超声波在搅拌摩擦焊接头(FSW)不同组织中的衰减,从超声C扫描图像中提取特征,计算了接头拉伸时的净工作面积.结果表明,检测图像特征与接头实测拉伸性能之间具有良好的相关性,证明了用超声波无损表征的方法预测FSW接头抗拉强度是可行的.

关键词：无损表征抗拉强度搅拌摩擦焊超声C扫描

金属杆内疲劳裂纹与振动/超声相互作用及其定量表征

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声学学报 2016年第4期41卷 507-514页

作者：刘斌刚铁万楚豪罗志伟栾亦琳哈尔滨工业大学先进焊接与连接国家重点实验室哈尔滨150001 黑龙江科技大学材料科学与工程学院哈尔滨150022

根据同步解调的原理,考察振动声调制检测输出信号中的调制成分,对金属杆内振动/超声在裂纹面上的相互作用进行了分析.制作了含有不同尺寸裂纹的铝杆试样,以扫频激励的方式得到合适的高频激励参数,分析输出信号中的调制信息,发现工件中... 详细信息

根据同步解调的原理,考察振动声调制检测输出信号中的调制成分,对金属杆内振动/超声在裂纹面上的相互作用进行了分析.制作了含有不同尺寸裂纹的铝杆试样,以扫频激励的方式得到合适的高频激励参数,分析输出信号中的调制信息,发现工件中的高频超声可分为两部分:一部分声波通过裂纹面,受到低频振动信号的调制,另一部分则保持不变。在此基础上对非线性调制模型进行了修正,并提出了一种用于裂纹检测的定量方法。与超声C扫描检测结果对比表明,此定量方法可用于估计金属杆中疲劳裂纹尺寸。

关键词：裂纹面疲劳裂纹定量表征输出信号同步解调高频超声裂纹尺寸超声能量低频振动裂纹检测

Interaction of major facilitator superfamily domain containing 2A with the blood-brain barrier

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Neural Regeneration Research 2025年第8期20卷 2133-2152页

作者： Yilun Ma Taiwei Dong Fei luan Juanjuan Yang Feng Miao Peifeng Wei College of Pharmacy and First Clinical Medical College Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina National Drug Clinical Trial Agency The Second Affiliated Hospital of Shaanxi University of Chinese Medicine/Xixian New District Central HospitalXi′anShaanxi ProvinceChina

The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly *** major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier *** plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain ***,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain *** paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier *** comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to *** will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic *** addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier lea

关键词： blood-brain barrier(BBB) caveolin-1 central nervous system docosahexaenoic acid endothelial cells lysophosphatidylcholine major facilitator superfamily domain containing 2A(MFSD2A) transcytosis

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厚板电子束焊缝的超声扇形扫描检测

黑龙江科技大学学报 2014年第6期24卷 621-626页

作者：栾亦琳王永东黑龙江科技大学材料科学与工程学院哈尔滨150022

针对传统超声斜角探伤法检测厚板焊缝宽度受限的问题,采用超声相控阵扇形扫描方法,对55 mm厚TC4电子束焊缝进行检测研究.对相控阵波束在TC4焊缝中的偏转聚焦特性及扇形扫描进行模拟分析,采用扇形扫描与D扫描、A扫描相结合的方法分析缺... 详细信息

针对传统超声斜角探伤法检测厚板焊缝宽度受限的问题,采用超声相控阵扇形扫描方法,对55 mm厚TC4电子束焊缝进行检测研究.对相控阵波束在TC4焊缝中的偏转聚焦特性及扇形扫描进行模拟分析,采用扇形扫描与D扫描、A扫描相结合的方法分析缺陷特征,给出缺陷的三维定位.结果表明：扇形扫描角度为30°～70°,采用双面检测的方法可以实现宽度有限的厚板焊缝的检测,扇形扫描图像能够更加直观地显示缺陷.在TC4电子束焊缝中检测出气孔、裂纹、未熔合和未焊透四种缺陷.通过合理设置坐标系,可以实现焊缝缺陷的三维定位,测得缺陷距离换能器楔块前沿的距离、埋藏深度和距离扫查起始位置的水平距离.

关键词：超声相控阵扇形扫描电子束焊缺陷

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多维度评价及优化黄芪瞬时高温灭菌工艺

中国农业科技导报 2024年第7期26卷 223-233页

作者：时晓宇焦连庆于敏田义新焦安妮栾依琳吉林省中医药科学院长春130012 吉林农业大学中药材学院长春130118

为优化黄芪瞬时高温灭菌(high temperature short time,HTST)工艺参数并多维度考察其对黄芪质量的影响,基于指标相关性的权重系数(criteria importance though intercrieria correlation,CRITIC)法采用正交设计优化黄芪灭菌工艺参数,以... 详细信息

为优化黄芪瞬时高温灭菌(high temperature short time,HTST)工艺参数并多维度考察其对黄芪质量的影响,基于指标相关性的权重系数(criteria importance though intercrieria correlation,CRITIC)法采用正交设计优化黄芪灭菌工艺参数,以灭菌温度、灭菌时间、药材粉碎粒度为考察因素,以灭菌率、5种化合物含量及1,1-二苯基-2-苦基肼自由基(1,1-diphenyl-2-picrylhydrazyl,DPPH·)清除率为考察指标,通过直观及方差分析评价灭菌对3个考察指标的影响;并运用液质联用技术(liquid chromatography-mass spectrometry,LC-MS)确认指纹图谱共有峰的结构,以偏最小二乘回归分析法分析共有峰与抗氧化活性的谱效关系。结果显示,灭菌温度是具有显著影响的因素(P<0.05),最佳灭菌工艺参数为灭菌温度(170±2)℃,灭菌时间5 s,粉碎粒度50目;按优化工艺灭菌后的3批样品微生物水平均符合药典规定,5种化合物含量及DPPH·清除率与灭菌前比较无明显变化;灭菌前后指纹图谱相似度均大于0.900;谱效学分析相关性结果与化合物单体抗氧化的试验结果及其结构特点基本一致。综上所述,瞬时高温灭菌对黄芪中微生物具有明显杀灭作用且对其质量无明显影响,表明该方法适用于黄芪药材灭菌。

关键词：黄芪瞬时高温灭菌指标相关性权重系数正交设计谱效关系

维普期刊数据库博看期刊

Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development

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Neural Regeneration Research 2025年第3期20卷 900-912页

作者： Baoqi Hu Rui Wang Hanyue Zhang Xiou Wang Sijia Zhou Bo Ma Yan luan Xin Wang Xinlin Chen Zhichao Zhang Qianyan Kang Department of Ophthalmology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’anShaanxi ProvinceChina Department of Ophthalmology The First Affiliated Hospital of Northwest UniversityXi’anShaanxi ProvinceChina Institute of Neurobiology Xi’an Jiaotong University Health Science CenterXi’anShaanxi ProvinceChina

The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell ***,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development ***,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo *** this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in ***,we used SOX2 and PAX6 immunostaining to identify retinal progenitor *** then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,***-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between ***,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,*** timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant *** study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina *** findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.

关键词： bipolar cells differentiation in vivo microglia Müller glia organotypic retinal explant culture postnatal retina development proliferation retinal progenitor cells

Encapsulating perovskite quantum dots into 3D COF for visible light-driven CO2 reduction

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Science China Chemistry 2025年

作者： Xinxin Wang Yucheng Jin Xiya Yang Qingyu luan Tianyu Wang Dongdong Qi Kang Wang Jianzhuang Jiang College of Chemistry and Materials Science Anhui Normal University Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of Chemistry and Chemical Engineering School of Chemistry and Biological EngineeringUniversity of Science and Technology Beijing

Lead halide perovskite quantum dots（LHP QDs） have been revealed to possess great potential in photocatalytic applications including CO2reduction, which however suffer from poor stability. Herein, a high crystalline hydrazine-linked three-dimensional（3D） covalent organic framework, USTB-17, was fabricated from the reaction between 12-connected building block and 4-connected 3,5,7-tetrakis（4-aldophenyl）-adamantane. Post-modification with Ni2+affords the metallic framework USTB-17（Ni）followed by sequential deposition of the CH3NH2PbI3（MAPbI3） perovskite QDs into its pores, generating the USTB-17（Ni）@MAPbI3composite. Powder X-ray diffraction analysis together with theoretical simulations and transmission electron microscopy discloses the crystalline nature of USTB-17, USTB-17（Ni）, and USTB-17（Ni）@MAPbI3with an unprecedented noninterpenetrated hpt topology. The close contact of QDs inside the COF pores with the Ni catalytic site locating at the pore surface of COF allows a rapid transfer of the photogenerated electrons in QDs to the Ni catalytic sites, enhancing the photocatalytic activity for CO2reduction. This endows USTB-17（Ni）@MAPbI3with efficient photocatalysis performance for photocatalytic CO2reduction with CO generation rate of 365 μmol g-1h-1and CO selectivity up to 96% under visible-light irradiation, 7 times higher than that of USTB-17（Ni）. After four cycles of reactions, the photocatalytic CO generation rate remains almost unchanged, demonstrating its excellent cycle stability.

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