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Out-of-Plane Compressive Behavior for UHMWPE/Polyurethane Composites after Hygrothermal Treatment

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Journal of Beijing Institute of Technology 2019年第1期28卷 176-183页

作者： Libao zhu Yongqing Li Xi zhu zixu zhu Department of Naval Architecture Engineering Naval University of Engineering

Quasi-static and high strain rate compressive behaviors and failure mechanisms of hygrothermal treated ultra-high molecular weight polyethylene/polyurethane(UHMWPE/PU)composites have been studied in this ***,the UHMWPE composites were immersed in water at 70℃.The out-ofplane compression test was then performed on the dry/wet state specimens at quasi-static states(0.001-0.01 s^(-1))and high strain rate states(800-2 400 s^(-1)).The split Hopkinson pressure bar(SHPB)was adopted in the dynamic tests and waveform shapers were used to smooth and control the incident *** results show that there are two platforms for the water absorption curve of UHMWPE *** absorption of moisture reduces the quasi-static compressive strength of the material while initially increasing,then decreasing the dynamic compressive *** plasticization,fiber/matrix interface degradation and void expansion are the main factors affecting the irregular change of static/dynamic compressive strength of UHMWPE composites.

关键词： ultra-high molecular weight polyethylene(UHMWPE)composite hygrothermal aging split Hopkinson pressure bar(SHPB) compression

Optomagnonically tunable whispering gallery cavity laser wavelength conversion

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Chinese Physics B 2023年第2期32卷 293-297页

作者：朱奕宁朱子虚裴安邦高永潘 International School Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

We achieve laser wavelength conversion in an optomagnonical whispering gallery cavity by adjusting the strength of the applied static magnetic field. Numerical simulations are carried out on a yttrium iron garnet(YIG) sphere under different cavity quality factors or coupling strength. It is found that a high cavity quality factor will not always mean a high cavity excitation field for Gaussian lasers with finite linewidth. On state of the art, the high cavity quality factor will always mean the higher lightwave conversion rate. In addition, we also find that increasing the mode coupling strength is beneficial to the conversion of the laser. Our study provides new insights into generation of highly precise tunable coherent light.

关键词： cavity optomagnonics YIG sphere laser modulation

Genome editing in plants with MAD7 nuclease

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Journal of Genetics and Genomics 2021年第6期48卷 444-451页

作者： Qiupeng Lin zixu zhu Guanwen Liu Chao Sun Dexing Lin Chenxiao Xue Shengnan Li Dandan Zhang Caixia Gao Yanpeng Wang Jin-Long Qiu State Key Laboratory of Plant Cell and Chromosome Engineering Center for Genome EditingInstitute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China

MAD7 is an engineered nuclease of the Class 2 type V-A CRISPR-Cas(Cas12 a/Cpf1)family with a low level of homology to canonical Cas12 a *** has been publicly released as a royalty-free nuclease for both academic and commercial ***,we demonstrate that the CRISPR-MAD7 system can be used for genome editing and recognizes T-rich PAM sequences(YTTN)in *** editing efficiency in rice and wheat is comparable to that of the widely used CRISPR-Lb Cas12 a *** develop two variants,MAD7-RR and MAD7-RVR that increase the target range of MAD7,as well as an M-AFID(a MAD7-APOBEC fusion-induced deletion)system that creates predictable deletions from 50-deaminated Cs to the MAD7-cleavage ***,we show that MAD7 can be used for multiplex gene editing and that it is effective in generating indels when combined with other CRISPR RNA *** the CRISPR-MAD7 system,we have obtained regenerated mutant rice and wheat plants with up to 65.6%efficiency.

关键词： MAD7 nuclease CRISPR-Cas12a Plant genome editing Royalty-free Commercial use

Semantic-driven method for designing 3D busbars

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Computer Aided Drafting,Design and Manufacturing 2017年第2期27卷 16-23页

作者： Shi Kanle zhu zixu Wu Zijian Zhang Hui Yong Junhai School of Software Tsinghua University Key Laboratory for Information System Security Ministry of Education of China Tsinghua National Laboratory for Information Science and Technology

Traditional busbar design is inefficient, costly, and error-prone because of frequent changes of requirements. This paper proposes a semantic-driven method for designing 3D busbars to solve this problem. The design process contains two main parts, namely, semantic-driven routing design and automatic routing segmentation. Semantic-driven routing design creates a relation table between electrical semantics and 3D modeling parameters, as well as helps designers create routings efficiently using electrical parameters as input. Automatic routing segmentation can convert routings into busbar segments that also include manufacturing information. Because the design operations are associated with one another, the resulting busbars can automatically be changed in real time when requirements are changed.

关键词： semantic-driven design busbar design busbar segmentation modeling change of requirement

夹芯复合材料耐压壳舱段仿真计算及临界环肋高度确定方法研究

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哈尔滨工业大学学报 2019年第5期51卷 155-162页

作者：朱子旭李永清朱锡朱礼宝海军工程大学舰船与海洋学院武汉430033

本文基于Abaqus有限元仿真软件,针对夹芯复合材料耐压壳舱段有效支撑的临界环肋高度问题进行了计算分析.论文首先结合相关试验结果,对仿真计算方法进行了验证.然后建立了共3个系列15个有限元模型,对在不同腹板铺层方式、不同尺寸的T型... 详细信息

本文基于Abaqus有限元仿真软件,针对夹芯复合材料耐压壳舱段有效支撑的临界环肋高度问题进行了计算分析.论文首先结合相关试验结果,对仿真计算方法进行了验证.然后建立了共3个系列15个有限元模型,对在不同腹板铺层方式、不同尺寸的T型截面舱段环肋结构支撑下的夹芯复合材料耐压壳长舱段进行了临界屈曲载荷的计算,并得到以下结论.通过设置环肋可以有效地增加夹芯复合材料耐压壳长舱段的稳定性.当环肋的支撑刚度增加到一定值时,长舱段的屈曲模态会从整体屈曲转变为被环肋边界限制在舱段范围内的的多段的单分段屈曲模态,该环肋高度称为环肋有效支撑的临界环肋高度.环肋有效支撑的临界高度可以通过屈曲载荷随腹板高度的增长趋势图中两段直线的交点位置来确定.当环肋高度大于临界环肋高度时,结构的分段屈曲载荷与环肋的属性关系不大,主要与夹芯圆柱壳自身的尺寸与材料属性有关.经计算,本文所分析的夹芯复合材料耐压壳结构其分段自身屈曲载荷可达7.0MPa.

关键词：夹芯复合材料耐压壳环肋屈曲损伤应力损伤有限元仿真

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复合材料夹芯梁屈曲破坏模式及极限承载

复合材料学报 2016年第5期33卷 991-997页

作者：陈悦朱锡李华东朱子旭海军工程大学舰船工程系武汉430033

为研究复合材料夹芯梁在轴压作用下的屈曲、后屈曲特性及承载能力,进行了试验研究与有限元仿真。首先,开展了系列复合材料夹芯梁屈曲特性试验,研究了铺层比例、梁长度、表层厚度及芯层厚度等因素对其屈曲、后屈曲破坏模式及极限承载的影... 详细信息

为研究复合材料夹芯梁在轴压作用下的屈曲、后屈曲特性及承载能力,进行了试验研究与有限元仿真。首先,开展了系列复合材料夹芯梁屈曲特性试验,研究了铺层比例、梁长度、表层厚度及芯层厚度等因素对其屈曲、后屈曲破坏模式及极限承载的影响;然后,基于非线性屈曲理论,采用三维内聚力界面单元模拟面芯脱粘,并引入初始预变形及材料损伤准则对复合材料夹芯梁在轴压下的屈曲特性及极限承载进行仿真研究。结果显示:界面脱粘是屈曲破坏的重要模式;仿真计算的极限承载与试验结果相比,误差控制在10%以内。所得结论表明该方法可有效预报复合材料夹芯梁的后屈曲路径、破坏模式及极限承载。

关键词：复合材料夹芯梁屈曲破坏模式承载能力

夹芯复合材料耐压壳工艺缺陷对承载能力的影响

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哈尔滨工程大学学报 2019年第2期40卷 260-265页

作者：朱子旭李永清朱锡陈悦海军工程大学舰船与海洋学院湖北武汉430033

为了确定工艺缺陷对夹芯复合材料耐压壳承载能力的影响程度,本文基于夹芯复合材料耐压壳静水压力试验的试验结果和数值计算结果,研究了工艺缺陷对夹芯耐压壳承载能力的影响规律。经分析发现在耐压壳成型过程中会出现三种类型的工艺缺陷... 详细信息

为了确定工艺缺陷对夹芯复合材料耐压壳承载能力的影响程度,本文基于夹芯复合材料耐压壳静水压力试验的试验结果和数值计算结果,研究了工艺缺陷对夹芯耐压壳承载能力的影响规律。经分析发现在耐压壳成型过程中会出现三种类型的工艺缺陷。结果表明:在工艺缺陷对耐压壳体的临界屈曲载荷有一定影响,但缺陷敏感度不高。本文所提出的夹心耐压壳结构制造工艺可行的。

关键词：夹芯复合材料结构耐压壳极限屈曲载荷工艺缺陷不圆度缺陷脱胶缺陷

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含面芯脱粘缺陷复合材料夹芯梁屈曲失效研究

华中科技大学学报（自然科学版） 2016年第7期44卷 40-45页

作者：陈悦朱锡李华东朱子旭海军工程大学舰船工程系湖北武汉430033

为研究面芯脱粘缺陷对复合材料夹层结构屈曲特性的影响,对含贯穿矩形面芯脱粘缺陷的复合材料夹芯梁进行了试验和仿真研究.轴向压缩试验发现:试件破坏模式为混合屈曲失效,承载过程可划分为轴向压缩、局部屈曲、混合屈曲和坍塌失效四个阶... 详细信息

为研究面芯脱粘缺陷对复合材料夹层结构屈曲特性的影响,对含贯穿矩形面芯脱粘缺陷的复合材料夹芯梁进行了试验和仿真研究.轴向压缩试验发现:试件破坏模式为混合屈曲失效,承载过程可划分为轴向压缩、局部屈曲、混合屈曲和坍塌失效四个阶段.在试验基础上,基于Abaqus非线性弧长算法,对复合材料夹芯梁的极限载荷及后屈曲路径进行模拟.采用三维内聚力单元模拟预制脱粘缺陷,从破坏模式和极限载荷两个方面与试验结果进行对比,误差为6.51%,验证了数值计算方法的可靠性.有限元分析发现:随芯层模量增加,极限荷载先非线性增长后线性增长;当缺陷因子为0.052时,极限荷载为完整结构的80%,为确保结构的承载特性,应在缺陷因子达到0.05前及时进行脱粘区域修补.

关键词：复合材料夹芯梁面芯脱粘缺陷屈曲极限荷载

含预裂缝复合材料缠绕圆柱壳轴压承载特性分析

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材料导报 2017年第7期31卷 150-154页

作者：陈悦朱锡朱子旭李华东海军工程大学舰船工程系武汉430033

为探究穿透裂缝对复合材料缠绕圆柱壳承载能力及失效模式的影响,首先开展不同壁厚含预裂缝复合材料缠绕圆柱壳轴向压缩试验。对于A系列厚壁圆柱壳,裂缝导致承载能力下降53.96%,失效模式由局部屈曲转化为裂缝扩展、脆性断裂;而B系列薄壁... 详细信息

为探究穿透裂缝对复合材料缠绕圆柱壳承载能力及失效模式的影响,首先开展不同壁厚含预裂缝复合材料缠绕圆柱壳轴向压缩试验。对于A系列厚壁圆柱壳,裂缝导致承载能力下降53.96%,失效模式由局部屈曲转化为裂缝扩展、脆性断裂;而B系列薄壁圆柱壳均发生局部屈曲,裂缝使承载能力下降12.59%。其次,采用有限元软件ABAQUS 6.14,基于非线性RIKS算法,建立轴压作用下含预裂缝复合材料圆柱壳极限承载能力计算模型,通过引入Hashin失效准则及损伤演化判据,预测结构渐进破坏模式及极限荷载。数值结果与试验数据吻合良好,最大误差为7.01%,验证了数值算法的可靠性。在此基础上,探讨裂缝方向、缠绕角度对含预裂缝复合材料圆柱壳极限承载的影响,可知:对于±55°螺旋铺层复合材料圆柱壳,随裂缝角度α增加,极限承载能力先升高再降低,当α=45°时,具备最大承载能力;对于含开缝角α=15°、45°、55°缠绕圆柱壳,随缠绕角θ增加,其承载能力呈先上升后下降趋势。且开缝角越小,缠绕角度对极限荷载的影响越大,当缠绕角θ=30°时,达到最大承载能力。

关键词：复合材料缠绕圆柱壳裂缝失效模式极限荷载