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A continuous-discontinuous cellular automaton method for cracks growth and coalescence in brittle material

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Acta Mechanica Sinica 2014年第1期30卷 73-83页

作者： Fei yan Xia-Ting Feng Peng-Zhi Pan Shao-jun Li State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Science

A method of continuous-discontinuous cellular automaton for modeling the growth and coalescence of multiple cracks in brittle material is presented. The method uses the level set to track arbitrary discontinuities, and calculation grids are independent of the discontinuities and no remeshing are required with the crack growing. Based on Grif- fith fracture theory and Mohr-Coulumb criterion, a mixed fracture criterion for multiple cracks growth in brittle mate- rial is proposed. The method treats the junction and coales- cence of multiple cracks, and junction criterion and coales- cence criterion for brittle material are given, too. Besides, in order to overcome the tracking error in the level set ap- proximation for crack junction and coalescence, a dichotomy searching algorithm is proposed. Introduced the above the- ories into continuous-discontinuous cellular automaton, the present method can be applied to solving multiple crack growth in brittle material, and only cell stiffness is needed and no assembled global stiffness is needed. Some numerical examples are given to shown that the present method is efficient and accurate for crack junction, coalescence and percolation problems.

关键词： Continuous-discontinuous cellular automatonmethod Multiple crack growth Discontinuous cellular au-tomaton junction criterion - Coalescence criterion

Application of grey relational analysis in sheet metal forming for multi-response quality characteristics

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 805-811页

作者： XIE yan-min YU Hu-ping CHEN jun RUAN Xue-yu National Die ＆ Mold CAD Engineering Research Center Shanghai Jiao Tong University Shanghai 200030 China

The theory of grey systems is a new technique for performing prediction, relational analysis and decision making in many areas. In this paper, the use of grey relational analysis for optimizing the square hole flanging process parameters with considerations of the multiple response (the average flanging height, regular flanging and maximum strain) is introduced. Various flanging parameters, such as the blank inner radius rb, blank inner width B0, are considered. An orthogonal array is used for the experimental design. Multiple response values are obtained using finite element analysis (FEA). Optimal process parameters are determined by the grey relational grade obtained from the grey relational analysis for multi-performance characteristics (flanging height, regular flanging and maximum strain). Analysis of variance (ANOVA) for the grey relational grade is implemented. The results showed good agreement with the experiment result. Grey relational analysis can be applied in multiple response optimi-zation designs.

关键词： Grey relational analysis Flanging Multiple response Optimization design

Creation and erasure of polar bubble domains in PbTiO_(3)films by mechanical stress and light illuminations

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Journal of Materiomics 2023年第4期9卷 626-633页

作者： Xingchen Zhang Hongying Chen Guo Tian Wenda yang Zhen Fan Zhipeng Hou Deyang Chen Min Zeng Minghui Qin Jinwei gao Xingsen gao jun-Ming Liu Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials and Institute for Advanced Materials South China Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou510006China Laboratory of Solid-State Microstructures and Innovation Center of Advanced Microstructures Nanjing UniversityNanjing210093China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringJiangsu Key Laboratory of Artificial Functional MaterialsNanjing UniversityNanjing210093China

The controllable manipulation of polar topological structures(*** bubble)in ferroelectric materials have been considered as a cornerstone for future programmable ***,we present the effective creation and erasure of polar bubble states PbTiO_(3)(PTO)multilayers trigged by mechanical stress and light illumination,*** was found that applying atomic force microscope(AFM)tip force can induced formation of nanoscale bubble domains from the initial monodomain ***,the created bubble domain can be eliminated by exposure to ultraviolet or infrared light *** above results can be understood by modulation of depolarization screening charges and bias fields,as reflected by scanning Kelvin potential microscopic(SKPM)observations,whereby the flexoelectric effect from the tip force tends to remove the screening charges on top surface and modulate the bias field that favors the formation of bubble state while light illumination tends to recover the screen charges and favor the monodomain *** results provide a good example for multi-field manipulation of polar topologies,which might create a new avenue towards the immerging new concept electronic devices.

关键词： Ferroelectric films Polar topologies Piezoresponse force microscopy

基于血清mirnas差异性表达分析糖尿病高危足的风险因素分析

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医学研究与战创伤救治 2024年第1期37卷 42-48页

作者：李秀贞王丛香王猛闫会霞杨越高娟娟张鹏河北省沧州中西医结合医院(沧州市二医院)内分泌糖尿病一科沧州061000 河北省沧州中西医结合医院(沧州市二医院)ICU科沧州061000

目的评估糖尿病(T2D)患者和T2D高危足患者以及非糖尿病患者的血清样本中的miRNAs表达模式。方法收集2021年6月至2022年6月期间在河北省沧州中西医结合医院内分泌科住院的92例T2D患者。其中46例被诊断为高危足但没有足部溃疡,为T2D高危足... 详细信息

目的评估糖尿病(T2D)患者和T2D高危足患者以及非糖尿病患者的血清样本中的miRNAs表达模式。方法收集2021年6月至2022年6月期间在河北省沧州中西医结合医院内分泌科住院的92例T2D患者。其中46例被诊断为高危足但没有足部溃疡,为T2D高危足组;其余患者为T2D组。选择在本院接受体检的46例糖耐量正常的健康人作为对照组。从所有参与者收集血液样本,采用了基于RT-qPCR的TLDA芯片血清样品的miRNA谱,并通过RT-qPCR对其中差异表达的miRNA进行验证。结果TLDA分析结果显示,在评估的754个miRNAs中,与对照组相比,两组T2D患者中有25个上调,118个下调。RT-qPCR验证显示,与对照组相比,包括miR-23、miR-195-5p、miR-205-5p、miR-203在内的4个miRNA的水平在T2D组和T2D高危足组患者中均显著增加(P<0.05)。此外,T2D高危足组患者的上述4个血清miRNA的水平高于T2D组患者(P<0.05)。在多变量分析中,以对照组为参考类别时,仅miR-195-5p(OR=6.9,95%CI:2.0~24.2,P=0.003)和miR-205-5p(OR=7.2,95%CI:1.6~32.0,P=0.009)与单纯T2D独立相关,和miR-195-5p(OR=6.9,95%CI:2.0~24.2,P<0.001)、miR-205-5p(OR=11.0,95%CI:2.8~43.2,P=0.001)与T2D高危足独立相关。当T2D组被作为参考类别时,仅miR-195-5p(OR=3.0,95%CI:1.6~5.7,P=0.001)和miR-205-5p(OR=2.3,95%CI:1.2~4.2,P=0.012)与T2D高危足独立相关。miR-195-5p和miR-205-5p在区分T2D组和对照组时的ROC曲线下面积(AUC)分别为0.74和0.70,在区分T2D高危足组和对照组时的AUC为0.87和0.84,在区分T2D组和T2D高危足组时的AUC为0.65和0.62。结论miR-195-5p、miR-205-5p可能成为T2D及高危足的新型风险指标,并可能在T2D及高危足的发病机制和进展中发挥重要作用。

关键词：糖尿病高危足血清 miRNAs 表达模式

Static softening behaviors of 7055 alloy during the interval time of multi-pass hot compression

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Rare Metals 2013年第3期32卷 241-246页

作者： Liang-Ming yan Jian Shen jun-Peng Li Bai-Ping Mao School of Materials Science and Engineering Innermongolia University of Technology Department of Processing Business General Research Institute for Nonferrous Metals Science and Technology Department Aluminum Corporation of China Limited

Multipass plain strain compression test of 7055 alloy was carried out on Gleeble 1500D thermomechanical simulator to study the effect of interval time on static softening behavior between two passes. Microstructural features of the alloy deformed with delay times varying from 0 to 180 s after achieving a reduction of ,-~52 % in the 13 stages was investigated through TEM and EBSD observations. The 14th pass of peak stresses after different delay times were gained. The peak stress decreases with the interstage delay time increasing, but the decreasing trend is gradually slower. Static recovery, metadynamic recrystallization, and/or static recrystallization can be found in the alloy during two passes. The recovery and recrystallization degree increases with longer interstage delay time. The static recovery is the main softening mechanism. Subgrain coalescence and subgrain growth together with particle-stimulated nucleation are the main nucleation mechanisms for static recrystallization.

关键词： 7055 aluminum alloy Hot compression Microstructure Interval time

Noonan Syndrome患儿临床特征及致病基因分析

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中国听力语言康复科学杂志 2024年第1期22卷 99-102页

作者：周虹段宏高建军郭刚内蒙古医科大学附属医院耳鼻咽喉头颈外科呼和浩特010000

努南综合征(Noonan syndrome,NS)为常染色体显性遗传病,临床特征上可有多系统损害,如独特的面部畸形、先天性心脏缺陷、身材矮小、隐睾、淋巴畸形、出血性疾病和骨骼畸形等,部分患者有听力障碍。临床上已有报道Noonan综合征是感音神经... 详细信息

努南综合征(Noonan syndrome,NS)为常染色体显性遗传病,临床特征上可有多系统损害,如独特的面部畸形、先天性心脏缺陷、身材矮小、隐睾、淋巴畸形、出血性疾病和骨骼畸形等,部分患者有听力障碍。临床上已有报道Noonan综合征是感音神经性聋的罕见病因。本文描述了1名双侧严重听力损失的Noonan综合征患者,成功行双侧人工耳蜗植入。2019年该患儿因神经性耳聋、特殊面容及生长发育问题就诊于首都医科大学附属儿童医院,通过全外显子组测序检测到PTPN11基因存在c.417G>C致病性变异,确诊为Noonan综合征1型。本研究的成功实施,有助于进一步明确NSPTPN11致病基因,为家族成员的遗传咨询及未来的优生优育咨询提供理论依据。

关键词： Noonan综合征感音神经性聋 PTPN11基因人工耳蜗植入

Reversible switching of Kondo resonance in a single-molecule junction

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Nano Research 2022年第2期15卷 1466-1471页

作者： Yuqing Xing Hui Chen Bin Hu Yuhan Ye Werner AHofer Hong-jun gao Institute of Physics Chinese Academy of Sciences and University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

The control of the Kondo effect is of great interest in single-molecule junction due to its potential applications in spin based ***,we demonstrate that the Kondo effect is reversibly switched on and off in an iron phthalocyanine(FePc)single-molecule junction by using a superconducting Nb *** a scanning tunneling microscope-based Nb-insulator-FePc-Au junction,we achieve a reversible switching between the Kondo dip and inelastic electronic tunneling spectra by simply adjusting the tip-sample distance to tune the tunnel coupling at low *** approaching the tip leads to the picking up of the molecule to the tip apex,which transfers the geometry of the single-molecule junction into a Nb-FePc-insulator-Au *** the molecule forms an effective magnetic impurity embedded into the superconducting ground states of the Nb tip,the out-gap Kondo dip switched to an in-gap Yu-Shiba-Rusinov *** results open up a new route for manipulating the Kondo effect within a single-molecule junction.

关键词： iron phthalocyanine(FePc) scanning tunneling microscope superconducting tip Kondo resonance inelastic electron tunneling Yu-Shiba-Rusinov states

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聚乳酸纳米填料增强复合材料的应用研究进展

现代纺织技术 2024年第1期32卷 130-139页

作者：邵烨华高召阳王龙飞田伟戚栋明严小飞浙江理工大学纺织科学与工程学院(国际丝绸学院) 杭州310018 浙江省现代纺织技术创新中心绍兴312000

随着环境污染问题逐渐严峻,自然资源消耗严重,生物基可降解材料不断被开发来替代传统石油基塑料,文章主要对生物基可降解材料聚乳酸(PLA)及纳米填料增强复合材料进行了综述。介绍了直接法和间接法合成聚乳酸的过程以及不同化学结构聚乳... 详细信息

随着环境污染问题逐渐严峻,自然资源消耗严重,生物基可降解材料不断被开发来替代传统石油基塑料,文章主要对生物基可降解材料聚乳酸(PLA)及纳米填料增强复合材料进行了综述。介绍了直接法和间接法合成聚乳酸的过程以及不同化学结构聚乳酸的物理和力学性能,阐述了不同形态纳米填料增强增韧聚乳酸的研究进展,以及在包装材料、生命医药、纺织等领域的主要应用以及存在的问题,并对聚乳酸及其纳米填料增强复合材料的未来应用进行展望,为其进一步研究和应用提供思路。

关键词：聚乳酸合成方法可降解纤维纳米填料复合材料

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姚沛雨基于“虚劳干血”辨治慢性心力衰竭

深圳中西医结合杂志 2024年第13期34卷 60-63页

作者：樊艳艳马永明高言歌开封市中医院河南开封475000

慢性心力衰竭是心系难治性疾病,姚沛雨教授临证40余年,在治疗心血管疾病方面经验丰富,从中医经典理论“虚劳干血”探讨慢性心力衰竭中医诊疗模式,总结本病为虚实夹杂,以虚为本,以实为标,病性为“虚”“瘀”“热”,病机为“干血形成”,... 详细信息

慢性心力衰竭是心系难治性疾病,姚沛雨教授临证40余年,在治疗心血管疾病方面经验丰富,从中医经典理论“虚劳干血”探讨慢性心力衰竭中医诊疗模式,总结本病为虚实夹杂,以虚为本,以实为标,病性为“虚”“瘀”“热”,病机为“干血形成”,治疗上以“缓中补虚”为准则,以“润络和血、虫动其瘀、清热防变”为治则,以期提高患者的生活质量。本文附验案一则。

关键词：慢性心力衰竭虚劳干血辨治思路