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New class of high-entropy pseudobrookite titanate with excellent thermal stability,low thermal expansion coefficient,and low thermal conductivity

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Journal of Advanced Ceramics 2022年第10期11卷 1654-1670页

作者： Jinyu WU Xiaohui MA Xiaoxia HU Liwen YAN Feng hou Jiachen LIU Anran GUO School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China

As a type of titanate,the pseudobrookite(MTi_(2)O_(5)/M_(2)TiO_(5))exhibits a low thermal expansion coefficient and thermal conductivity,as well as excellent dielectric and solar spectrum absorption ***,the pseudobrookite is unstable and prone to decomposing below 1200℃,which limits the practical application of the *** this paper,the high-entropy pseudobrookite ceramic is synthesized for the first *** pure high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5) with the pseudobrookite structure and the biphasic high-entropy ceramic composed of the highentropy pseudobrookite(Cr,Mn,Fe,Al,Ga)_(2)TiO_(5) and the high-entropy spinel(Cr,Mn,Fe,Al,Ga,Ti)_(3)O_(4) are successfully prepared by the in-situ solid-phase reaction *** comparison between the theoretical crystal structure of the pseudobrookite and the aberration-corrected scanning transmission electron microscopy(AC-STEM)images of high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5) shows that the metal ions(M and Ti ions)are disorderly distributed at the A site and the B site in high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5),leading to an unprecedentedly high configurational entropy of high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5).The bulk high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5) ceramics exhibit a low thermal expansion coefficient of 6.35×10^(−6) K^(−1) in the temperature range of 25-1400℃ and thermal conductivity of 1.840 W·m^(−1)·K^(−1) at room temperature,as well as the excellent thermal stability at 200,600,and 1400℃.Owing to these outstanding properties,high-entropy(Mg,Co,Ni,Zn)Ti_(2)O_(5) is expected to be the promising candidate for high-temperature thermal *** work has further extended the family of different crystal structures of high-entropy ceramics reported to date.

关键词： high-entropy pseudobrookite (Mg,Co,Ni,Zn)Ti_(2)O_(5) (Cr,Mn,Fe,Al,Ga)_(2)TiO_(5) high conformational entropy thermal expansion coefficient thermal conductivity

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提肛运动训练辅助治疗对混合痔术后皮瓣水肿患者的情况分析

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四川生理科学杂志 2024年第1期46卷 168-170页

作者：侯晶晶许元红朱文亚开封市中医院肛肠科河南开封475000

目的:探究混合痔术后皮瓣水肿患者应用提肛运动训练辅助治疗对炎症介质水平及肛缘水肿的影响。方法:选取我科2019年12月至2021年3月期间105例混合痔术后皮瓣水肿患者作为研究对象,均给予地奥司明片等基础治疗,对照组52例给予康复新液治... 详细信息

目的:探究混合痔术后皮瓣水肿患者应用提肛运动训练辅助治疗对炎症介质水平及肛缘水肿的影响。方法:选取我科2019年12月至2021年3月期间105例混合痔术后皮瓣水肿患者作为研究对象,均给予地奥司明片等基础治疗,对照组52例给予康复新液治疗,观察组53例增加提肛运动训练辅助治疗,1 m后,采用数字评分法(Numerical rating scale,NRS)评分评估两组患者疼痛水平,对比两组患者治疗效果包括肛门疼痛消失时间、切缘水肿消失时间、分泌物消失时间、创面愈合率、创面愈合时间、白细胞介素-6(Interleukin-6,IL-6)、肿瘤坏死因子α(Tumor necrosis factor-α,TNF-α)水平变化等,及对比两组不良反应总发生率。结果:干预1 m后,观察组患者肛缘水肿消失时间、分泌物消失时间及疼痛消失时间均少于对照组(P<0.05),干预1 m后,NRS评分低于对照组(P<0.05);干预1 m后,观察组TNF-α及IL-6水平均低于对照组(P<0.05);干预1 m后,观察组患者创面愈合时间少于对照组(P<0.05);干预1 m后,观察组患者不良反应总发生率9.43%低于对照组36.54%(P<0.05)。结论:提肛运动辅助治疗对混合痔术后患者进行干预效果明显,能够有效改善患者切缘水肿情况,有助于缩短创面愈合时间,且不良反应较少。

关键词：康复新液提肛运动训练混合痔皮瓣水肿

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Effects of proteins on magnesium degradation-static *** conditions

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Journal of Magnesium and Alloys 2023年第4期11卷 1332-1342页

作者： Ruiqing hou Frank Feyerabend Heike Helmholz Vasil M.Garamus Regine Willumeit-Römer School of Materials Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou UniversityNo.100 Science AvenueZhengzhou 450001China Institute of Metallic Biomaterials Helmholtz-Zentrum Hereon(Hereon)Max-Planck-Str.1Geesthacht 21502Germany

The interaction between organic molecules and biomaterial surfaces determines the fate of biomaterials during their service life,which is also the research hotspots in the field of *** understand the mechanism of protein interaction with magnesium(Mg)degradation,alloying elements,immersion time,protein concentration and surface conditions have been previously considered for the effect of proteins on Mg ***,fluid flow,as one of the critical factors,drew little attention in this *** the present study,the effect of bovine serum albumin(BSA)and fetal bovine serum(FBS)on Mg degradation was compared under static and dynamic *** results revealed that both BSA and FBS slightly decreased the degradation rate of Mg in Hanks’balanced salt solution(HBSS)under static immersion due to the protein adsorption and the formation of a Ca/P-rich top layer on Mg surface,whereas under dynamic flow condition the degradation of Mg was significantly accelerated in the presence of BSA or *** reasons seemed to stem from the weakened protein adsorption on Mg surface in this case and the dynamically enhanced interaction between proteins and ions/products in solutions,which largely weaken the combination of the top Ca/P-rich layer with the inner corrosion product *** results highlight the importance of testing conditions for Mg characterization in vitro and the synergistic effect between different parameters on Mg degradation.

关键词： Flow Bovine serum albumin Fetal bovine serum Protein adsorption

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参数智能优化变分模态分解的输电短路信号提取

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制造业自动化 2024年第4期46卷 87-92,101页

作者：裴东锋刘勇李勇苗靓侯帅国网河北省电力有限公司邯郸供电分公司邯郸056000 河北工程大学信息与电气工程学院邯郸056000

输电短路信号因非线性含噪难以准确提取,影响后续故障诊断正确率。为此,提出参数智能优化变分模态分解的输电短路信号提取方法。引入峰值密度实时监测粒子群种群密度,设计权重自适应更新策略,以避免种群多样性缺失导致算法陷入局部最优... 详细信息

输电短路信号因非线性含噪难以准确提取,影响后续故障诊断正确率。为此,提出参数智能优化变分模态分解的输电短路信号提取方法。引入峰值密度实时监测粒子群种群密度,设计权重自适应更新策略,以避免种群多样性缺失导致算法陷入局部最优;然后,建立变分模态分解(Variational Mode Decomposition,简称VMD)算法优化求解的适应度函数,并采用上述改进粒子群算法实现VMD参数智能优化下的输电短路信号提取。采用典型测试函数验证了改进粒子群算法具有比其他算法更好的搜索速度和稳定性,并进一步验证了提出的参数智能优化变分模态分解方法可以较好提取非线性含噪输电短路信号,可提高故障诊断正确率。

关键词：变分模态分解参数优化粒子群优化惯性权重输电短路信号提取

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Dynamics of maize grain drying in the high latitude region of Northeast China

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Journal of Integrative Agriculture 2022年第2期21卷 365-374页

作者： CHU Zhen-dong MING Bo LI Lu-lu XUE Jun ZHANG Wan-xu hou Liang-yu XIE Rui-zhi hou Peng WANG Ke-ru LI Shao-kun Agricultural College Shihezi University/Key Laboratory of Oasis Eco-AgricultureXinjiang Production and Construction CropsShihezi 832000P.R.China Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and EcologyMinistry of Agriculture and Rural AffairsBeijing 100081P.R.China Heilongjiang Bayi Agricultural University Daqing 163000P.R.China

A high grain moisture content at harvest has been an important problem in the high latitude region of Northeast China, and it is closely related to the genotypes of varieties, local meteorological factors and planting management. However, delayed harvest at a low temperature could not effectively reduce the grain moisture content. In this study, we continuously observed the grain drying during the late stage of different maturing types of maize varieties in Daqing, Heilongjiang Province, China in 2016 and 2017. A two-segment linear model was used to analyze the different stages of the drying processes: 1) Twosegment linear model fitting can divide the grain drying process of all varieties into two separate linear drying processes with different slopes. 2) During the rapid drying stage, the drying was faster at a higher temperature. The rate of slow drying was influenced by air vapor pressure. 3) The moisture content and meteorological factors when the drying rate turns from one stage into the other were not consistent between varieties and years. After entering the frost period, temperatures below 0℃ will significantly reduce the rate of grain drying. 4) Due to the short growth period of early-maturing varieties, the drying time was prolonged, and the grain moisture content was lower than that of the mid-late maturing varieties. Local meteorological conditions do not allow the drying of mid-late maturing varieties to achieve a lower moisture content. When the temperature falls below 0℃, the drying rate of grain decreases markedly. Therefore, one feasible way to solve the problem of high moisture content is to replace the early-maturing varieties and implement the corresponding cultivation techniques.

关键词： grain drying maize Northeast China two-segment linear model

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All-plasmonic optical leaky-wave antenna with a low sidelobe level

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Photonics Research 2023年第9期11卷 1500-1508页

作者： GUANG ZHU Zhou BAO-JIE CHEN GENG-BO WU SHI-WEI QU CHI hou CHAN School of Electronic Science and Engineering University of Electronic Science and Technology of China(UESTC)Chengdu 611731China State Key Laboratory of Terahertz and Millimeter Wave City University of Hong KongHong Kong 999077China Department of Electrical Engineering City University of Hong KongHong Kong 999077China

Optical antennas have received considerable attention in recent years due to their unique ability to convert localized energy to freely propagating radiation and vice *** level(SLL)is one of the most crucial parameters in antenna design.A low SLL is beneficial to minimize the antenna interference with other optical *** a plasmonic optical leaky-wave antenna with low SLL is *** spatial frequency by periodically modulating the electric-field amplitude in a plasmonic gap waveguide enables a free-space coupled wave out of the *** the same time,precise control of the aperture fields by the modulation depth allows for reducing *** results indicate that the proposed design can achieve a high directivity of 15.8 dB and a low SLL of-20 dB at the wavelength of 1550 nm.A low SLL below-15 dB is experimentally demonstrated within the wavelength range from 1527 to 1570 *** addition,the low-SLL property is further verified by comparing it with a uniformly modulated *** modulating the guided waves in the plasmonic gap waveguide in different forms,the aperture fields can be flexibly arranged to achieve arbitrary wavefront *** bridges the gap between guided and free-space waves and empowers plasmonic integrated devices to control free-space light,thus enabling various free-space functions.

关键词： antenna waveguide optical

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Effects of surface grinding for scratched alloy 690TT tube in PWR nuclear power plant:Microstructure and stress corrosion cracking

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Journal of Materials Science & Technology 2022年第18期113卷 229-245页

作者： Bin Wu Hongliang Ming Fanjiang Meng Yifeng Li Guangqing He Jianqiu Wang En-hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shanghai Nuclear Engineering Research and Design Institute Ltd.Co. Shanghai 200233China Instrumental Analysis and Research Center Shanghai UniversityShanghai 200444China Department of Materials Science Fudan UniversityShanghai 200433China Shanghai Electric Nuclear Power Equipment Co. Ltd.Shanghai 201306China

Alloy 690TT tube samples with different scratch depths were repaired by grinding treatments using abra-sive papers of two different particle *** microstructure and stress corrosion cracking(SCC)behavior were studied in *** grinding,the plastic accumulation zone vulnerable to SCC was ***,some residual slip steps remained in the scratched *** tests lasting 1000,2000,3000,and 4000 h show that the sensitivity and risk of SCC in the scratched area are decreased by *** using abrasive particles of a smaller size is more ***,deep scratches remained hazardous even after the grinding.

关键词： Alloy 690TT Scratch Surface Stress corrosion High temperature corrosion Intergranular corrosion

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星载激光雷达视轴监测系统设计

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红外与激光工程 2024年第6期53卷 61-70页

作者：万渊李蕊张扬袁金如熊恒周国威刘继桥侯霞中国科学院上海光学精密机械研究所空天激光技术与系统部上海201800 中国科学院大学材料与光电研究中心北京100049 上海卫星工程研究所上海201109

提出了一种针对星载激光雷达在轨高精度光轴监测与标定需求的多光轴监测方法,该方法基于主动激光光源。通过使用785 nm的激光,分束后分别照射到星敏感器的基准棱镜和接收望远镜的取光棱镜,反射信号被聚焦至监视相机的焦平面,实现了对接... 详细信息

提出了一种针对星载激光雷达在轨高精度光轴监测与标定需求的多光轴监测方法,该方法基于主动激光光源。通过使用785 nm的激光,分束后分别照射到星敏感器的基准棱镜和接收望远镜的取光棱镜,反射信号被聚焦至监视相机的焦平面,实现了对接收光轴及星敏光轴的精确监测。此外,监视相机还同步采集发射激光的部分能量,用于测量监测发射光轴。文中详细描述了光学系统的设计流程及关键组件的优化方案,并通过地面真空环境试验及在轨监测数据进行了验证。设计结果表明,各监视通道的成像质量达到了衍射极限,收发光轴的设计精度分别为0.09μrad和2.28μrad,关键组件取光棱镜的温控精度达到了±0.2℃。地面的真空热光试验结果进一步验证了该方案的高精度光轴监视能力,收发光轴的监测精度均优于3μrad。最后通过分析激光雷达入轨后的测量数据,确认了视轴监测系统的工作稳定性,成功实现了在轨的高精度光轴监视。该研究成果为星载激光雷达提供了一种有效的在轨高精度光轴监测与标定解决方案。

关键词：主动遥感星载激光雷达光轴监测单元光轴匹配

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结合卷积神经网络和注意力机制的LSTM采空区地表沉降预测方法

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测绘通报 2024年第6期 53-58,170页

作者：高墨通杨维芳刘祖昱曹小双张瑞琪侯宇豪兰州交通大学测绘与地理信息学院甘肃兰州730070 地理国情监测技术应用国家地方联合工程研究中心甘肃兰州730070 甘肃省地理国情监测工程实验室甘肃兰州730070 金川集团股份有限公司龙首矿甘肃金昌737100

为解决采空区地表塌陷区域时序预测中存在的监测点空间特征难以提取的问题,本文提出了一种可以提取监测点关键空间特征的CNN-Attention-LSTM组合神经网络模型。首先,增加作为特征输入的邻近监测点个数,使用卷积神经网络(CNN)提取由多个... 详细信息

为解决采空区地表塌陷区域时序预测中存在的监测点空间特征难以提取的问题,本文提出了一种可以提取监测点关键空间特征的CNN-Attention-LSTM组合神经网络模型。首先,增加作为特征输入的邻近监测点个数,使用卷积神经网络(CNN)提取由多个监测点构成的多维时间序列的空间特征;其次,将提取后的多维特征时序输入多层感知器(MLP)中计算注意力权重,并与特征输入作Hadamard积,实现特征输入的注意力权重分配;然后,利用长短期记忆神经网络(LSTM)进行回归预测;最后,通过全连接层,整合输出目标监测点的预测值。本文以龙首矿西二采区地表塌陷区域为例,给出其地表沉降监测数据预测结果,并与实际采集的数据作对比。结果表明,引入注意力机制的CNN-Attention-LSTM的组合模型比CNN-LSTM模型和LSTM模型精度更高,且增加有效特征输入能够显著提升CNN-Attention-LSTM模型的预测精度。

关键词：时间序列建模地表沉降预测深度学习注意力机制长短期记忆

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补骨脂抗肿瘤作用机制研究进展

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中草药 2024年第10期55卷 3529-3538页

作者：刘改廷勾文峰许飞飞郭江红王跃飞李祎亮侯文彬天津中医药大学天津301617 北京协和医学院&中国医学科学院放射医学研究所天津市放射医学与分子核医学重点实验室天津300192

补骨脂Psoraleae Fructus具有温肾助阳、纳气平喘、温脾止泻等功能,常用于心血管疾病、肾炎、骨质疏松症、癌症和白斑病等的治疗。现代研究表明,补骨脂中主要含有香豆素类、黄酮类、单萜酚类等多种化合物,其中含有多种抗肿瘤活性成分,... 详细信息

补骨脂Psoraleae Fructus具有温肾助阳、纳气平喘、温脾止泻等功能,常用于心血管疾病、肾炎、骨质疏松症、癌症和白斑病等的治疗。现代研究表明,补骨脂中主要含有香豆素类、黄酮类、单萜酚类等多种化合物,其中含有多种抗肿瘤活性成分,包括补骨脂素、补骨脂定、补骨脂二氢黄酮、补骨脂二氢黄酮甲醚、补骨脂查耳酮和补骨脂酚等。对乳腺癌、肝癌、肺癌、胃癌、结肠癌及前列腺癌等恶性肿瘤细胞具有较好的增殖抑制作用,其作用机制主要包括增殖凋亡、周期阻滞、氧化应激、多药耐药、自噬、迁移和侵袭。通过对补骨脂中活性成分抗肿瘤的作用机制进行综述,探讨其抗肿瘤研究现状及其开发应用前景,为补骨脂抗肿瘤的研究与发展提供有用的信息。

关键词：补骨脂抗肿瘤增殖凋亡氧化应激周期阻滞多药耐药补骨脂素补骨脂定补骨脂二氢黄酮

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