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Optimization of tensile strength for new type acetone-urea-formaldehyde furan resin using uniform design

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China Foundry 2011年第1期8卷 30-35页

作者： Lin Shengjun Zhao Wei Li Yuancai tong siyi Wang Wenqing School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China Guangxi Yuchai Machinery Company Limited Yulin 537005 Guangxi China

In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design *** independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 *** 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression *** (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data *** t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,*** method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan *** investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.

关键词： acetone-urea-formaldehyde furan resin 24 h tensile strength single factor experiment uniform design stepwise regression

基于概率成像方法的装配式剪力墙地震作用下损伤演化分析

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建筑结构学报 2022年第7期43卷 72-80页

作者：王娟姜绍飞崔二江佟思逸福州大学土木工程学院福建福州350108 福建省土木工程多灾害防治重点实验室福建福州350108

为了有效监控地震作用下装配式剪力墙裂缝损伤发展过程,提出了基于压电导波的改进概率成像分析方法。通过布设阵列传感器将待检测区域划分为多个子区域,根据发射与接收信号的相干函数提取有效信号;以该有效信号为输入信号,分别计算各子... 详细信息

为了有效监控地震作用下装配式剪力墙裂缝损伤发展过程,提出了基于压电导波的改进概率成像分析方法。通过布设阵列传感器将待检测区域划分为多个子区域,根据发射与接收信号的相干函数提取有效信号;以该有效信号为输入信号,分别计算各子区域中基于信号能量特征差异系数的损伤指标,并利用概率统计方法对该损伤指标进行筛分,排除环境因素的影响;由损伤概率成像算法对检测区域内产生的所有裂缝位置进行叠加成像并提取图像阈值,从而实现装配式剪力墙在地震过程中裂缝损伤发生的判断、定位及演化分析。通过装配式框架-剪力墙结构的振动台试验验证了所提方法及裂缝损伤演化分析的有效性。所提出的改进损伤概率成像分析方法可直观有效地检测装配式剪力墙在地震作用下裂缝损伤的发生、位置及演化过程,可用于装配式结构的损伤监测。

关键词：装配式剪力墙裂缝损伤压电导波损伤指标概率成像方法

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陶粒原料对烧胀陶粒膨胀性能的影响

非金属矿 2022年第2期45卷 6-9页

作者：童思意刘玉林刘长淼中国地质科学院郑州矿产综合利用研究所河南郑州450006 国家非金属矿资源综合利用工程技术研究中心河南郑州450006 西北地质科技创新中心陕西西安7100541

采用分析纯化学试剂为原料制备陶粒,研究助熔剂K_(2)CO_(3)用量、发泡剂SiC用量、Al_(2)O_(3)用量及焙烧温度对陶粒膨胀率的影响。结果表明,助熔剂K_(2)CO_(3)用量为13%,发泡物质SiC用量为0.15%,Al_(2)O_(3)用量在9%~15%范围,焙烧温度在... 详细信息

采用分析纯化学试剂为原料制备陶粒,研究助熔剂K_(2)CO_(3)用量、发泡剂SiC用量、Al_(2)O_(3)用量及焙烧温度对陶粒膨胀率的影响。结果表明,助熔剂K_(2)CO_(3)用量为13%,发泡物质SiC用量为0.15%,Al_(2)O_(3)用量在9%~15%范围,焙烧温度在1160~1200℃范围时,可制备内部孔结构良好的膨胀陶粒。陶粒膨胀性能的影响机理为:发泡物质SiC在一定温度范围内产生气体,促进多孔形成;助熔剂K_(2)CO_(3)和Al_(2)O_(3)用量影响陶粒内液相生成温度及液相产生量,从而影响陶粒的膨胀。

关键词：烧胀陶粒原料组成焙烧温度膨胀率

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我国固体废弃物制备陶粒的研究进展

矿产保护与利用 2019年第3期39卷 140-150页

作者：童思意刘长淼刘玉林马超中国地质科学院郑州矿产综合利用研究所河南郑州450006 国家非金属矿资源综合利用工程技术研究中心河南郑州450006 西北地质科技创新中心陕西西安710054

固废大量堆存对大气、土壤、水体和生物圈产生污染和危害。陶粒是一种性能优异、应用广泛的新兴材料。部分固废与陶粒原料的契合度很高,是极佳的陶粒基体材料,利用固废制备陶粒产品可规模化消纳利用固废,同时形成良好的社会环境效益和... 详细信息

固废大量堆存对大气、土壤、水体和生物圈产生污染和危害。陶粒是一种性能优异、应用广泛的新兴材料。部分固废与陶粒原料的契合度很高,是极佳的陶粒基体材料,利用固废制备陶粒产品可规模化消纳利用固废,同时形成良好的社会环境效益和可观的经济利益。通过文献调研,汇总了陶粒的国家标准指标要求;从陶粒原料、生产工艺及其涉及的主要原理总结了陶粒制备的理论基础;列举并总结了陶粒的研究现状;总结与展望了陶粒的行业发展与市场环境现状。利用固废制备陶粒已成为规模化消纳固废、资源化获取陶粒的重要途径。

关键词：固体废弃物陶粒工艺资源化

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浙北地区国审良种‘玉铃铛’枣避雨栽培技术

安徽林业科技 2024年第5期50卷 49-51页

作者：朱静夷童思怡谢莹荣卓晶江玉新王兆成湖州职业技术学院浙江湖州313099 湖州市枣致富创意农旅工作室浙江湖州313000 湖州南浔世荣湖羊养殖家庭农场浙江湖州313000

‘玉铃铛’枣是安徽省“十二五”期间通过国家林木审定委员会审定的唯一林木良种。其丰产性强,树势健壮,枣果个大饱满、口感酥脆、含糖量高。本文介绍了‘玉铃铛’枣引种至浙北平原地区后采用的避雨设施栽培配套技术,该技术优质高效,对... 详细信息

‘玉铃铛’枣是安徽省“十二五”期间通过国家林木审定委员会审定的唯一林木良种。其丰产性强,树势健壮,枣果个大饱满、口感酥脆、含糖量高。本文介绍了‘玉铃铛’枣引种至浙北平原地区后采用的避雨设施栽培配套技术,该技术优质高效,对助力安徽省优质良种资源推广应用和浙北乡村经济发展发挥重要作用。

关键词：玉铃铛枣浙北地区避雨栽培

ARGA-Unet:Advanced U-net segmentation model using residual grouped convolution and attention mechanism for brain tumor MRI image segmentation

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虚拟现实与智能硬件（中英文） 2024年第3期6卷 203-216页

作者： siyi XUN Yan ZHANG Sixu DUAN Mingwei WANG Jiangang CHEN tong tong Qinquan GAO Chantong LAM Menghan HU Tao TAN Faculty of Applied Sciences Macao Polytechnic UniversityMacao 999078China Jinan Branch of China Telecom Co.Ltd. Jinan 250000China School of Physics and Electronics Shandong Normal UniversityJinan 250000China Department of Dardiovascular Medicine Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310000China Clinical School of Medicine Hangzhou Normal UniversityHangzhou 310000China Hangzhou Institute of Cardiovascular Diseases Hangzhou 310000China Shanghai Key Laboratory of Multidimensional Information Processing Shanghai 200000China School of Communication&Electronic Engineering East China Normal UniversityShanghai 200000China Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghai 200000China College of Physics and Information Engineering Fuzhou UniversityFuzhou 350000China

Background Magnetic resonance imaging(MRI)has played an important role in the rapid growth of medical imaging diagnostic technology,especially in the diagnosis and treatment of brain tumors owing to its non invasive characteristics and superior soft tissue ***,brain tumors are characterized by high non uniformity and non-obvious boundaries in MRI images because of their invasive and highly heterogeneous *** addition,the labeling of tumor areas is time-consuming and *** To address these issues,this study uses a residual grouped convolution module,convolutional block attention module,and bilinear interpolation upsampling method to improve the classical segmentation network *** influence of network normalization,loss function,and network depth on segmentation performance is further *** In the experiments,the Dice score of the proposed segmentation model reached 97.581%,which is 12.438%higher than that of traditional U-net,demonstrating the effective segmentation of MRI brain tumor *** In conclusion,we use the improved U-net network to achieve a good segmentation effect of brain tumor MRI images.

关键词： Brain tumor MRI U-net Segmentation Attention mechanism Deep learning

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Lu2O3基激光透明陶瓷的研究进展

人工晶体学报 2024年第12期53卷 2043-2058页

作者：赵文海陶世旭童思意唐健左传东曹永革麻朝阳松山湖材料实验室中科皓烨(东莞)材料科技有限责任公司中国科学院物理研究所

倍半氧化物Lu2O3因具有优异的热力学性能、低声子能量和强晶体场等特点,成为近红外和中红外光谱（1～3μm）范围内的宽带发射高功率激光基体材料的优秀候选者之一,近年来受到人们的广泛关注。Lu2O3的熔点高达2 450℃,单晶生长极为困难,... 详细信息

倍半氧化物Lu2O3因具有优异的热力学性能、低声子能量和强晶体场等特点,成为近红外和中红外光谱（1～3μm）范围内的宽带发射高功率激光基体材料的优秀候选者之一,近年来受到人们的广泛关注。Lu2O3的熔点高达2 450℃,单晶生长极为困难,限制了其应用发展。但Lu2O3属于立方晶系,具有光学各向同性,因此制备Lu2O3基透明陶瓷成为一种可行的方案。透明陶瓷可以在较低的温度下（晶体熔点的60%～80%）烧结制备大尺寸样品,同时烧结周期相较于晶体生长周期大幅缩减,更有利于大量生产,因此制备Lu2O3基透明陶瓷作为新型激光介质材料更有潜力被广泛应用于科学研究、工业生产和日常生活。本文总结了基于稀土离子(Nd3+、Er3+、Yb3+、Tm3+、Ho3+)掺杂的Lu2O3基激光透明陶瓷的制备工艺及其性能参数的最新研究进展。未来,Lu2O3基激光陶瓷的开发将聚焦在大尺寸、高功率输出、低散射特性、高热稳定性、复合结构设计等方面以推动高性能固体激光器的发展。

关键词：透明陶瓷 Lu2O3 激光陶瓷倍半氧化物固体激光器激光增益介质

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Genome-Wide Identification of the F-box Gene Family and Expression Analysis under Drought and Salt Stress in Barley

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 229-251页

作者： Lantian Zhang siyi Wang Yuyu Chen Mengyuan Dong Yunxia Fang Xian Zhang Tao tong Ziling Zhang Junjun Zheng Dawei Xue Xiaoqin Zhang College of Life and Environmental Sciences Hangzhou Normal UniversityHangzhou310036China

The F-box protein-encoding gene family plays an essential role in plant stress *** present study,126 non-redundant F-box genes were identified in barley(Hordeum vulgare L.,Hv).The corresponding proteins contained 165–887 amino acid residues and all were amphiphilic,except 5 *** analysis of F-box protein sequences in barley and stress-related F-box protein sequences in wheat and Arabidopsis thaliana(At)was used to classify barley F-box genes are divided into 9 subfamilies(A–I).A structure-based sequence alignment demonstrated that F-box proteins were highly conserved with a total of 10 conserved *** total,124 F-box genes were unevenly distributed on 7 chromosomes;another 2 genes have not been anchored *** gene structure analysis revealed high variability in the number of exons and introns in F-box *** analysis of expression profiles and phylogenetic tree analysis,a total of 12 F-box genes that may be related to stress tolerance in barley were *** the 12 detected F-box genes,8 and 10 were upregulated after drought and salt stress treatments,respectively,using quantitative real-time polymerase chain reaction(qRT-PCR).This study is the first systematic analysis conducted on the F-box gene family in barley,which is of great importance for clarifying this family’s bioinformatic characteristics and elucidating its function in barley stress *** results will serve as a theoretical reference for subsequent research on molecular regulation mechanisms,genetic breeding,and improvement.

关键词： Drought and salt stress barley expression analysis F-box gene family phylogenetic analysis

Instability characteristics of a co-rotating wingtip vortex pair based on bi-global linear stability analysis

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Chinese Journal of Aeronautics 2021年第5期34卷 1-16页

作者： Zepeng CHENG siyi QIU Yang XIANG Chun SHAO Miao ZHANG Hong LIU School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China Shanghai Aircraft Design and Research Institute Commercial Aircraft Corporation of China Ltd.Shanghai 201210China

The Stereo Particle Image Velocimetry(SPIV)technology is applied to measure the wingtip vortices generated by the up-down symmetrical split ***,the temporal biglobal Linear Stability Analysis(bi-global LSA)is performed on this nearly equal-strength corotating vortex pair,which is composed of an upper vortex(vortex-u)and a down vortex(vortex-d).The results show that the instability eigenvalue spectrum illustrated by(ωr,ω_(i))contains two types of branches:discrete branch and continuous *** discrete branch contains the primary branches of vortex-u and vortex-d,the secondary branch of vortex-d and coupled branch,of which all of the eigenvalues are located in the unstable half-plane ofω_(i)>0,indicating that the wingtip vortex pair is temporally *** contrast,the eigenvalues of the continuous branch are concentrated on the half-plane ofω_(i)<0 and the perturbation modes correspond to the freestream *** the primary branches of vortex-u and vortex-d,Mode P_(u) and Mode Pd are the primary perturbation modes,which exhibit the structures enclosed with azimuthal wavenumber m and radial wavenumber n,***,the results of stability curves for vortex-u and vortex-d demonstrate that the instability growth rates of vortex-u are larger than those of vortex-d,and the perturbation energy of Mode P_(u) is also larger than that of Mode ***,the perturbation energy of Mode P_(u) is up to 0.02650 and accounts for 33.56%percent in the corresponding branch,thereby indicating that the instability development of wingtip vortex is dominated by Mode P_(u).By further investigating the topological structures of Mode P_(u) and Mode Pd with streamwise wavenumbers,the most unstable perturbation mode with a large azimuthal wavenumber of m=5-6 is identified,which imposes on the entire core region of *** large azimuthal wavenumber perturbation mode can suggest the potential physical-based flow control strategy by manipulating it.

关键词： Bi-global linear stability analysis Perturbation mode SPIV Vortex flow Winglet Wingtip vortex