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Study on an automatic multi-pin insertion system for preparing Z-pin composite laminates

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Chinese Journal of Aeronautics 2014年第2期27卷 413-419页

作者： Song qinghua Li Yong qi junwei Wen Liwei Xiao Jun Ni Jinhui College of Material Science and Technology Nanjing University of Aeronautics and Astronautics

As a three-dimensional layer enhancement technology, the Z-pin technology is suitable for manufacturing composite prepreg laminates and can also effectively improve their interlaminar properties. In order to manufacture Z-pin composite parts efficiently, this paper proposes a transi- tional insertion system, and according to the technical requirements of the transitional insertion process and the functional requirements of the transitional insertion platform, proposes a transition insertion plan which can insert multiple Z-pins into a carrier. A prototype machine has been designed and made, and a series of function debugging and verification experiments have been car- ried out on the machine. Some problems show up during the experiments, but based on the analysis of the reasons, this paper provides lots of solutions, and finally demonstrates the feasibility and practical value of the system. The results show that the system meets all technical requirements of the Z-pin insertion process. It is capable to insert multiple Z-pins into a foam carrier; as a result, the system is as much as 5 times more efficient than existing equipment, and the deviation for the insertion distance can be controlled within 0.3 mm. This Z-pin transitional insertion platform pro- motes the use of Z-pins in national defense and lays the foundation for commercializing the Z-pin technology.

关键词： Composite materialsInsertion Multi-pin Three-dimensional Z-pin

Electrospun nanofibrous membranes with antimicrobial activity for air filtration

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Chinese Chemical Letters 2024年第10期35卷 147-157页

作者： Guangyao Wang Zhitong Xu Ye qi Yueguang Fang Guiling Ning junwei Ye State Key Laboratory of Fine Chemicals and School of Chemical Engineering Dalian University of TechnologyDalian 116012China Engineering Laboratory of Boric and Magnesic Functional Material Preparative and Applied Technology Dalian 116024China

Air pollution,including airborne pathogens and particulate matter(PM),has become a prominent issue affecting human health and *** air filtration materials do not meet the requirements for efficient PM capture or do not instantly kill pathogens,leading to increased risk of direct/indirect contact transmission and infection due to the accumulation of pathogens during *** nanofibrous membranes have emerged as a promising platform due to their rich porous structure,finer fiber diameters,good internal connectivity,and the ability to easily incorporate active chemicals for antimicrobial *** this review,antimicrobial mechanisms of nanofibrous membranes for air filtration and PM capture mechanisms of nanofibers were firstly investigated,and various types of electrospun nanofibrous membranes with different antimicrobial agents for efficient air filtration were described in detail,including organic antimicrobial agents,inorganic antimicrobial agents and metal-organic *** hope this work could provide a better practical insight for designing novel electrospun nanofibrous membranes with antimicrobial efficacy for efficient air filtration.

关键词： Electrospinning Nanofibrous membrane Antimicrobial Particulate matter Airfiltration

Selenocysteine methyltransferase SMT catalyzed the synthesis of Se-methylselenocysteine to regulate the accumulation of glucosinolates and sulforaphane in broccoli

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Horticultural Plant Journal 2024年第5期10卷 1151-1164页

作者： qi Wu junwei Wang Yuxiao Tian Chunyan Zhou Shuxiang Mao qiuyun Wu Ke Huang College of Horticulture Hunan Agricultural UniversityChangshaHunan 410128China Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding Ministry of EducationChangshaHunan 410128China Key Laboratory for Vegetable Biology of Hunan Province ChangshaHunan 410128China

Selenocysteine methyltransferase(SMT)is a key enzyme involved in the Se metabolism pathway,and it is responsible for the catalysis of Se-methylselenocysteine(SeMSC)compound *** studies showed that selenium treatment activated SMT expression and promoted the accumulation of glucosinolates(GSLs)and sulforaphane,but the roles and functional mechanisms of SMT in mediating GSLs and sulforaphane synthesis remain *** this study,we identified the BoSMT gene in broccoli and uncovered its roles in mediating GSLs *** assays revealed that BoSMT is involved in SeMSC biosynthesis in *** importantly,the contents of GSLs and sulforaphane were significantly increased in the BoSMT-overexpressing broccoli lines but decreased in the knockdown lines,suggesting that BoSMT played a positive role in regulating GSLs and sulforaphane *** evidence indicated that BoSMT-mediated overaccumulation of GSLs and sulforaphane might be due to the increase in the endogenous SeMSC *** with the mock(water)treatment,selenite-induced significantly increases of the SeMSC content in the BoSMT-knockdown plants partially compensated the phenotype of GSLs and sulforaphane *** with the mock treatment,exogenous SeMSC treatment significantly increased the contents of GSL and sulforaphane and activated GSL synthesis-related gene expression,suggesting that SeMSC acted as a positive regulator for GSL and sulforaphane *** findings provided novel insights into selenium-mediated GSLs and sulforaphane *** genetic manipulation of BoSMT might be a useful strategy for improving the dietary nutritional values of broccoli.

关键词： Selenocysteine methyltransferase Transgenic broccoli Se-methylselenocysteine Glucosinolate sulforaphane Selenium

BoMyrosinase plays an essential role in sulforaphane accumulation in response to selenite treatment in broccoli

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Horticultural Plant Journal 2024年第2期10卷 488-502页

作者： qiuyun Wu qi Wu Yuxiao Tian Chunyan Zhou Shuxiang Mao junwei Wang Ke Huang College of Horticulture Hunan Agricultural UniversityChangshaHunan 410128China Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding Ministry of EducationChangshaHunan 410128China Key Laboratory for Vegetable Biology of Hunan Province ChangshaHunan 410128China Key Laboratory for Evaluation and Utilization of Gene Resources of Horticultural Crops Ministry of Agriculture and Rural Affairs of ChinaChangshaHunan 410128China

Sulforaphane, a naturally specialized metabolite, plays significant roles in human disease prevention and plant defense. Myrosinase(MY) is a key gene responsible for the catalysis of sulforaphane formation, but the molecular mechanisms through which MY regulates sulforaphane biosynthesis in plants remains largely unknown. Here, we discovered that the change of sulforaphane content in broccoli sprouts caused by exogenous selenite treatments is positively related to BoMY expression. BoMY overexpression in the Arabidopsis thaliana tgg1 mutants could dramatically increase myrosinase activity and sulforaphane content in the rosette leaves of 35S::BoMY/tgg1 and rescue its ***, an obvious increase of myrosinase activity and sulforaphane content was displayed in transgenic BoMY-overexpressed broccoli *** addition, a 2 033 bp promoter fragment of BoMY was isolated. Yeast one-hybrid(Y1H) library screening experiment uncovered that one bHLH transcription factor, BoFAMA, could directly bind to BoMY promoter to activate its expression, which was further evidenced by Y1H assay and dual-luciferase reporter assay. BoFAMA is a selenite-responsive transcription factor that is highly expressed in broccoli leaves;its protein is solely localized to nucleus. Additionally, genetic evidence suggested that the knockdown of FAMA gene in Arabidopsis thaliana could significantly decrease sulforaphane yield by inhibiting the expression of myrosinase genes. Interestingly, exogenous selenite supply could partially restore the low level of sulforaphane content in transgenic Arabidopsis FAMA-silencing plants. Our findings uncover a novel function of FAMAMY module in the regulation of selenite-mediated sulforaphane synthesis and provide a new insights into the molecular mechanism by which selenite regulates the accumulation of sulforaphane in plants.

关键词： Brassica oleracea var.italica Myrosinase BoMY Sulforaphane Selenite treatment

Study on the Influence of Airgun Excitation Conditions on Airgun Signals and Travel Time Variation Measurements

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Earthquake Research in China 2019年第2期33卷 336-353页

作者： XIANG Ya YANG Runhai WANG Bin ZHOU Yunyao LU Yongqing WU Huan qi junwei PENG Jing Key Laboratory of Earthquake Geodesy Institute of SeismologyCEAWuhan 430071China Yunnan Earthquake Agency Kunming 650224China

Because of the different excitation conditions of the airgun source,there will be subtle differences in airgun *** time variation of airgun signals often mix into source information which can’t fully reflect the evolution of the *** article uses the airgun signals from the Binchuan Transmitting Seismic Station to analyze the airgun signal′s characteristics of phase and *** conducted a comparative analysis of the effects of the pair difference method and the deconvolution method on eliminating the influence of the excitation conditions in travel time *** results show that:(1)The pressure pulse and its subsequent wave of airgun source wavelet are less affected by excitation conditions that we can use it to obtain high-precision excitation moments.(2)Deconvolution can improve the correlation of the airgun signal.(3)The pair difference method can’t eliminate the influence of excitation conditions in travel time *** can reduce excitation condition interference and the influence of the excitation condition in the travel time variation after deconvolution of the vertical signal is significantly reduced.

关键词： Airgun source Pair difference Deconvolution Travel time variation Correlation

Analysis of blocking slurry diffusion parameters for a new self-starting drainage anchor cable

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Journal of Earth Science 2024年

作者： WANG Xu GE qi Lü Chengcheng SHU junwei SUN Hongyue Sino-Italy Ningbo Ecological Park Holding Group Co.，Ltd Ocean College， Zhejiang University College of Civil Engineering and Architecture， Zhejiang University School of Civil Engineering， Nanjing Forestry University

A new self-starting drainage anchor that combines prestressed anchor cables with self-starting drainage is proposed. The novelty of the self-starting drainage method is the realization of the drainage and anchoring in the one inclined borehole. Reduction in the number of boreholes can greatly decrease the construction cost and duration of the project. The adverse effect of drilling construction disturbance on the slope is reduced. To tackle the possible blockage of the drainage cavity due to slurry leakage during the solidification process after finishing grouting in the blocking section. To this end， a theoretical equation for the slurry diffusion radius under slurry self-weight pressure boundary conditions is deduced. The result is verified for precision through comparison with numerical simulation. The findings reveal that the permeability coefficient of rock and soil mass makes the most significant impact on the slurry diffusion radius， succeeded by the length of the grouting blocking section， slurry initial setting time， and drilling inclination in descending order of influence. With the 5% mass ratio of a "711" type slurry quick-setting agent， the maximum slurry diffusion radius can be reduced from 0.925m to 0.449m， a reduction of 0.476m， which is comparatively more recommended.

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预浸料先进拉挤成型的固化传热过程数值模拟

复合材料学报 2020年第6期37卷 1496-1504页

作者：姜碧羽齐俊伟刘小林南京航空航天大学材料科学与技术学院南京210001 上海飞机制造有限公司航空制造技术研究所上海200135

对M21C碳纤维/环氧树脂复合材料预浸料在先进拉挤成型过程中的温度与固化度曲线进行了研究。使用DSC测得M21C预浸料在升温与恒温状态下的固化反应动力学方程,用于树脂固化反应的计算。基于有限元软件,结合有限差分法与体积控制法编写脚... 详细信息

对M21C碳纤维/环氧树脂复合材料预浸料在先进拉挤成型过程中的温度与固化度曲线进行了研究。使用DSC测得M21C预浸料在升温与恒温状态下的固化反应动力学方程,用于树脂固化反应的计算。基于有限元软件,结合有限差分法与体积控制法编写脚本解决热传导与树脂固化反应的计算,从而得到温度与固化度曲线,并在先进拉挤生产中测得实际的温度与固化度曲线,结果表明计算与实测曲线基本吻合,因此验证了算法的可行性。改变先进拉挤的工艺参数(加热温度区间、拉挤速度)再进行模拟计算,通过计算结果优化工艺参数,得到帽形梁先进拉挤三区间加热的理想工艺参数:模具加热温度区间为160-180-200℃;拉挤速度为1 cm/60 s。

关键词：先进拉挤固化有限差分法体积控制法热传导

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基于降维算法和等效杆长的可展结构精度分析

航空学报 2017年第6期38卷 143-150页

作者：祁俊威王春洁丁建中北京航空航天大学机械工程及自动化学院北京100083 北京航空航天大学北京市数字化设计与制造重点实验室北京100083

考虑铰链间隙和杆件尺寸误差的不确定性并通过概率统计方法对其进行研究,提出了一种基于单变量降维算法(UDRM)和等效杆长模型的可展结构精度分析方法。利用UDRM将可展结构的精度性能函数解耦为多个杆件尺寸误差的独立作用形式,建立精度... 详细信息

考虑铰链间隙和杆件尺寸误差的不确定性并通过概率统计方法对其进行研究,提出了一种基于单变量降维算法(UDRM)和等效杆长模型的可展结构精度分析方法。利用UDRM将可展结构的精度性能函数解耦为多个杆件尺寸误差的独立作用形式,建立精度分析模型。引入等效杆长模型,等效杆件替代原杆件进行精度计算。将铰链间隙与原始杆件尺寸误差合并到等效杆件的尺寸误差中,同时证明了等效杆长尺寸误差近似服从正态分布。以某卫星可展开天线为算例,结合高斯求积公式求解展开状态下精度指标的分布期望和方差。通过与蒙特卡罗模拟(MCS)和一次二阶矩(FOSM)法计算结果的对比验证了本文精度分析方法的正确性和高效性。

关键词：铰链间隙尺寸误差可展开结构精度分析降维算法等效杆长

复合材料固化工艺的直热模具温度场均匀性分析

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复合材料学报 2021年第9期38卷 2946-2955页

作者：陆阳齐俊伟肖军石甲琪南京航空航天大学材料科学与技术学院南京210001

针对复合材料固化成型工艺的直热模具温度场均匀性进行了研究。建立模具温度场和复合材料固化反应温度场的耦合传热学模型,并对该模型进行有限元建模仿真分析。针对影响模具表面温度均匀性的主要因素,即电加热管的间距和功率,设计正交... 详细信息

针对复合材料固化成型工艺的直热模具温度场均匀性进行了研究。建立模具温度场和复合材料固化反应温度场的耦合传热学模型,并对该模型进行有限元建模仿真分析。针对影响模具表面温度均匀性的主要因素,即电加热管的间距和功率,设计正交试验优化,优化后模具表面最大温差为3.5℃,达到行业标准。此外,对影响温度场均匀性的其他因素,即加热管与模具的接触热阻、复合材料层合板厚度进行了探讨,接触热阻的存在使得模具表面最大温差达到7.24℃,模具加热到指定温度多用时800 s,降低了效率。研究层合板对模具温度均匀性的影响时发现未加入复合材料时模具表面最大温差为4.44℃,加入层合板耦合后最大温差为3.5℃;厚度为毫米级时,层合板对直热模具表面温度均匀性影响不大。

关键词：复合材料直热模具温度场均匀性固化反应动力学温度场耦合数值模拟正交试验优化