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China Foundry 2024年第2期21卷 101-115页

作者： Hao-ran Zhou Hao yang huai-qian Li Ying-chun Ma Sen Yu Jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

一种基于超像素和改进U-net的多模态脑部肿瘤图像分割方法

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小型微型计算机系统 2022年第1期43卷 91-97页

作者：胡春燕司明明陈玮上海理工大学光电信息与计算机工程学院上海200093

针对多模态脑部肿瘤图像分割难度较大和对脑部肿瘤边缘区域的分割不足等问题,本文将多模态脑部肿瘤图像分割任务分成两部分解决.第一部分是对脑部肿瘤轮廓区域的分割,先用超像素分割算法对图像进行预处理简化图像的表示形式,再提取每个... 详细信息

针对多模态脑部肿瘤图像分割难度较大和对脑部肿瘤边缘区域的分割不足等问题,本文将多模态脑部肿瘤图像分割任务分成两部分解决.第一部分是对脑部肿瘤轮廓区域的分割,先用超像素分割算法对图像进行预处理简化图像的表示形式,再提取每个超像素区域的灰度直方图,通过皮尔逊相关系数计算每个超像素区域的相似度,最后用均值漂移算法对剩余的直方图进行迭代运算,完成对脑部肿瘤图像轮廓区域的分割.通过在2D脑部肿瘤图像LGG数据集上的大量实验分析,本文的肿瘤轮廓分割模型可以很好的分割出肿瘤轮廓.第二部分用本文改进的U-net算法对脑部肿瘤图像轮廓区域进行精细的多模态分割.在多模态脑部肿瘤图像数据库Brats2019进行大量的实验,结果表示本文算法能够很好的细分出脑部肿瘤区域.

关键词：脑肿瘤 MRI图像分割超像素均值漂移 3D U-net

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Mechanical and damping performances of TPMS lattice metamaterials fabricated by laser powder bed fusion

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China Foundry 2024年第4期21卷 327-333页

作者： yan-peng Wei huai-qian Li Jing-jing Han Ying-chun Ma Hao-ran Zhou Jing-chang Cheng Jian Shi Zhi-quan Miao Bo Yu Feng Lin National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China

Lattice metamaterials based on three-period minimum surface(TPMS)are an effective means to achieve lightweight and high-strength materials which are widely used in various fields such as aerospace and ***,its vibration and noise reduction,and damping properties have not been fully ***,in this study,the TPMS structures with parameterization were designed by the method of surface migration,and the TPMS structures with high forming quality was manufactured by laser powder bed fusion(LPBF).The mechanical properties and energy absorption characteristics of the beam and TPMS structures were studied and compared by quasi-static *** modal shapes of the beam lattice structures and TPMS structures were obtained by the free modal analysis,and the damping properties of two structures were obtained by modal *** the two structures after heat treatment with the same porosity of 70%,the yield strength of the beam lattice structure reaches 40.76 MPa,elastic modulus is 20.38 GPa,the energy absorption value is 32.23 MJ·m^(-3),the damping ratio is 0.52%.The yield strength,elastic modulus,energy absorption value,and damping ratio of the TPMS structure are 50.74 MPa,25.37 GPa,47.34 MJ·m^(-3),and 0.99%,*** results show that TPMS structures exhibit more excellent mechanical properties and energy absorption,better damping performance,and obvious advantages in structural load and vibration and noise reduction compared with the beam lattice structures under the same porosity.

关键词： lattice metamaterials TPMS energy absorption damping laser powder bed fusion

紫茎泽兰对大鼠肠道结构和肠道黏膜免疫屏障的影响

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草业学报 2022年第6期31卷 211-220页

作者：崔玉晶高佩文娟 OKYERE Kumi Samuel 胡延春四川农业大学动物医学院四川成都611130

为探究紫茎泽兰对动物肠道损伤及致毒机制,本试验选取16只7周龄雄性SD大鼠经7 d适应期后随机分为对照组(饲喂不含紫茎泽兰饲料,10 g·100 g^(-1)BW)与试验组(饲喂含30%紫茎泽兰饲料,10 g·100 g^(-1)BW),试验周期为14 d,试验结束后取各... 详细信息

为探究紫茎泽兰对动物肠道损伤及致毒机制,本试验选取16只7周龄雄性SD大鼠经7 d适应期后随机分为对照组(饲喂不含紫茎泽兰饲料,10 g·100 g^(-1)BW)与试验组(饲喂含30%紫茎泽兰饲料,10 g·100 g^(-1)BW),试验周期为14 d,试验结束后取各肠段(取十二指肠、空肠、回肠、盲肠、结肠和直肠)组织样品,观察结构损伤,计数免疫细胞,测定sIgA(secretory immunoglobulin A,sIgA)和炎性细胞因子分泌量。结果表明:与对照组相比,紫茎泽兰可使十二指肠绒毛出血及顶端轻度坏死脱落,肠绒毛高度、隐窝深度及其比值极显著增加(P<0.01);空肠充血并伴有绒毛顶端糜烂性坏死脱落,绒毛高度及绒毛高度与隐窝深度比值极显著增加(P<0.01);回肠大量肠绒毛顶端凝固性坏死,并伴有出血与炎性浸润,绒毛高度、隐窝深度及其比值极显著增加(P<0.01);盲肠水肿及充血;结肠淋巴细胞增多、直肠大量淋巴细胞浸润及淋巴细胞增生,其中以回肠和直肠机械损伤最为严重,回肠评分增加722.36%,直肠评分增加976.00%;试验组各肠段上皮内淋巴细胞(intestinal intraepithelial lymphocytes,IELs)、固有层淋巴细胞(lamina propria lymphocytes,LPLs)和杯状细胞(goblet cells,GCs)数量极显著增加(P<0.01),同时还可极显著增加sIgA的分泌量(P<0.01),极显著增加促炎因子IL-1β、IL-2、TNF-α和IFN-γ的表达量(P<0.01),极显著降低抑炎因子IL-4、IL-10的表达(P<0.01),激活肠道炎症反应,从而破坏肠道黏膜免疫屏障,造成肠道损伤。

关键词：紫茎泽兰肠道结构肠道黏膜免疫

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Serum Alanine Aminotransferase Is Associated with Metabolic Syndrome and 10-year Risk of Cardiovascular Disease

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Biomedical and Environmental Sciences 2019年第2期32卷 121-125页

作者： MA Li Na DU Rui CHENG Di LIN Lin WU Xue yan hu chun yan DAI Meng XU Yu XU Min JIANG Lei LI Mian LU Jie Li BI Yu Fang WANG Wei Qing NING Guang Rui Jin Hospital Shanghai Jiao Tong University School of Medicine Shanghai Institute of Endocrine and Metabolic Diseases

Metabolic syndrome(MetS) is a cluster of metabolic disorders including obesity, hypertension, hyperglycemia, elevated triglyceride levels, and low high-density lipoprotein cholesterol(HDL-C) levels. In recent years, t... 详细信息

关键词： ALT HDL CVD LDL SBP BMI

Effect of ellagitannin metabolites ellagic acid and urolithins A-D on the non-enzymatic glycation of human serum albumin and inhibiting mechanisms

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Food Science and human Wellness 2024年

作者： Lu Zhang chun-yan Peng Wen-na Zhou Fei-yan Lu Lin-ju Xu Qing-hui Wen Xing Xie Zong-cai Tu National R&D Center of Freshwater Fish Processing College of Life Science Jiangxi Normal University State Key Laboratory of Food Science and Resources Nanchang University

Effect of ellagitannins gut microbiota metabolites ellagic acid (EA) and urolithin A-urolithin D (UroA-UroD) on human serum albumin (HSA) glycation were firstly evaluated in this research. The inhibition mechanisms were investigated by methylglyoxal (MGO) trapping and radical scavenging ability assays， docking studies and Nano LC-Orbitrap-MS/MS technology. Results indicated that the inhibition of urolithins on HSA glycation was highly positive correlated with the number of phenolic hydroxy groups. Addition of UroD and EA could effectively enhance the content of free amino group， suppress dicarbonyl compounds and advanced glycation end-products (AGEs) formation， alleviated tryptophan and protein oxidation， inhibited HSA amyloid-like aggregation. They could also trap MGO and scavenge DPPH· and ABTS·+. Molecular docking indicated that EA and UroA-UroD interact with HSA mainly through hydrogen bound and hydrophobic interaction， among which two or three hydrogen bonds were formed. The number of glycation sites were reduced from 11 to 10， 10， 7， and 10， respectively， when 90 μmol/L of EA， UroA， UroC and UroD were added. However， weak inhibition was observed on UroA and UroB. These findings can provide scientific evidence for the application of ellagitannins-rich foods in alleviating diabetic complications.

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Variation Characteristics of Root Traits of Different Alfalfa Cultivars under Saline-Alkaline Stress and their Relationship with Soil Environmental Factors

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 29-43页

作者： Tian-Jiao Wei Guang Li yan-Ru Cui Jiao Xie Xing-Ai Gao Xing Teng Xin-Ying Zhao Fa-chun Guan Zheng-Wei Liang Northeast Agricultural Research Center of China Jilin Academy of Agricultural SciencesChangchun130033China Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun130102China

Soil salinization is the main factor that threatens the growth and development of plants and limits the increase of *** is of great significance to study the key soil environmental factors affecting plant root traits to reveal the adaptation strategies of plants to saline-alkaline-stressed soil *** this study,the root biomass,root morphological parameters and root mineral nutrient content of two alfalfa cultivars with different sensitivities to alkaline stress were analyzed with black soil as the control group and the mixed saline-alkaline soil with a ratio of 7:3 between black soil and saline-alkaline soil as the saline-alkaline treatment *** the same time,the correlation analysis of soil salinity indexes,soil nutrient indexes and the activities of key enzymes involved in soil carbon,nitrogen and phosphorus cycles was carried *** results showed that compared with the control group,the pH,EC,and urease(URE)of the soil surrounding the roots of two alfalfa cultivars were significantly increased,while soil total nitrogen(TN),total phosphorus(TP),organic carbon(SOC),andα-glucosidase activity(AGC)were significantly decreased under saline-alkaline *** was no significant difference in root biomass and root morphological parameters of saline-alkaline tolerant cultivar GN under saline-alkaline *** number of root tips(RT),root surface area(RS)and root volume(RV)of AG were reduced by 61.16%,44.54%,and 45.31%,respectively,compared with control *** ratios of K^(+)/Na^(+),Ca^(2+)/Na^(+)and Mg^(2+)/Na^(+)of GN were significantly higher than those of AG(p<0.05).The root fresh weight(RFW)and dry weight(RDW),root length(RL),RV and RT of alfalfa were positively regulated by soil SOC and TN,but negatively regulated by soil pH,EC,and URE(p<0.01).Root Ca^(2+)/Na+ratio was significantly positively correlated with soil TN,TP and SOC(p<0.01).The absorption of Mg and Ca ions in roots is significantly negatively regulated by soilβ-glucosidase ac

关键词： Saline-alkaline stress alfalfa root traits soil environmental factors correlation analysis

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低频率射频辉光放电的研究

质谱学报 2021年第6期42卷 1156-1164页

作者：郭长娟胡帆胡春燕朱辉华南师范大学化学学院广东广州510006 广州禾信仪器股份有限公司广东广州510663

辉光放电电离源可用来检测固态、液态及气态样品,目前主要用于无机固体样品的元素分析和定量检测。本研究将低频率射频辉光放电(Lf-RFGD)与飞行时间质谱仪(TOF MS)联用用于分析液体和气体样品。研究了电离腔真空度、进样管尺寸、辅助气... 详细信息

辉光放电电离源可用来检测固态、液态及气态样品,目前主要用于无机固体样品的元素分析和定量检测。本研究将低频率射频辉光放电(Lf-RFGD)与飞行时间质谱仪(TOF MS)联用用于分析液体和气体样品。研究了电离腔真空度、进样管尺寸、辅助气压力、放电频率及电极板压差对电离效率的影响。最优分析条件为:电离腔真空度约30 Pa,进样管长150 mm、内径0.25 mm,辅助气压强约1.0 MPa,放电频率2 MHz,电极板压差约100 V。在此条件下,放电功率约20 W,对液体样品的检出限约0.1 pg、对挥发性样品的检出限约20 mg/m^(3),检测半峰分辨率约3000(FWHM)。将Lf-RFGD TOF MS应用于实际药品溶液和挥发性有机物(VOCs)的检测。本仪器对药品溶液的检测灵敏度与常用检测仪器相比无优势,但对挥发性有机物的检测效果较好,为开发低成本的VOCs检测仪器提供了有吸引力的选择。

关键词：低频率射频辉光放电(GD) 飞行时间质谱(TOF MS)

气膜孔分布对DD6单晶高温合金高周疲劳断裂行为的影响

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材料工程 2017年第4期45卷 84-89页

作者：胡春燕刘新灵陶春虎曹春晓北京航空材料研究院北京100095 航空材料检测与评价北京市重点实验室北京100095

利用带不同电液束加工气膜孔分布的DD6单晶气冷叶片模拟试样,研究其在常温下的高周疲劳性能,并对试样断口及断口侧面形貌进行宏观与微观观察。结果表明:在相同的实验条件下,气膜孔的存在对试样高周疲劳寿命的影响较大,无孔试样的平均寿... 详细信息

利用带不同电液束加工气膜孔分布的DD6单晶气冷叶片模拟试样,研究其在常温下的高周疲劳性能,并对试样断口及断口侧面形貌进行宏观与微观观察。结果表明:在相同的实验条件下,气膜孔的存在对试样高周疲劳寿命的影响较大,无孔试样的平均寿命约为带3排孔试样的4倍,但是气膜孔布局对疲劳寿命的影响相对较小。通过断口宏观与微观观察发现,无孔试样呈线源特征,而1~3排孔试样裂纹均从气膜孔附近起源,呈多源特征。根据断口和晶体学理论推测,对于无孔、1排孔和多排孔试样的中间部位,裂纹沿{001}滑移面扩展;而对于多排孔试样的上下2排孔孔周的裂纹沿{111}滑移面扩展。采用有限元方法分析4种不同试样孔边应力场的分布规律,数值模拟分析结果与试样的断裂位置及形貌吻合。

关键词： DD6单晶高温合金气冷叶片气膜孔疲劳性能断裂行为

气膜孔分布对DD6单晶高温合金持久性能及断裂行为的影响

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材料工程 2016年第5期44卷 93-100页

作者：胡春燕刘新灵陶春虎曹春晓北京航空材料研究院北京100095 航空材料检测与评价北京市重点实验室北京100095

研究在980℃/300MPa条件下不同气膜孔分布对DD6单晶气冷叶片模拟试样持久性能及断裂行为的影响。结果表明:在相同的温度和应力条件下,气膜孔的分布是影响模拟试样持久寿命的主要因素;随着气膜孔排数的增加,持久寿命呈规律性下降,而带1... 详细信息

研究在980℃/300MPa条件下不同气膜孔分布对DD6单晶气冷叶片模拟试样持久性能及断裂行为的影响。结果表明:在相同的温度和应力条件下,气膜孔的分布是影响模拟试样持久寿命的主要因素;随着气膜孔排数的增加,持久寿命呈规律性下降,而带1排孔、2排孔试样的持久寿命与不带孔的持久寿命略长。通过断口微观和金相组织观察发现,不带孔试样的断裂方式为微孔聚集型断裂,断口上分布着大量方形小平面特征,断口附近纵剖面上可见明显的心部裂纹;而带气膜孔试样的持久变形主要出现在气膜孔区域,断口整体氧化较严重,方形小平面特征减少,韧窝特征明显增加,断口附近纵剖面上气膜孔处均可见裂纹及氧化形貌。基于晶体塑性理论分析了不同孔分布下孔边应力的分布规律,模拟结果显示在气膜孔周边存在应力集中和应力重分布,数值模拟分析结果与试样的断裂位置及形貌吻合。

关键词： DD6单晶高温合金气冷叶片气膜孔持久性能断裂行为