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Improving Ultrasonic Testing by Using Machine Learning Framework Based on Model Interpretation Strategy

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 174-186页

作者： Siqi shi shijie jin Donghui Zhang jingyu Liao Dongxin Fu Li Lin NDT&E Laboratory Dalian University of TechnologyDalian 116024China China Nuclear Industry 23 Construction Co. Ltd.Beijing 101300China

Ultrasonic testing(UT)is increasingly combined with machine learning(ML)techniques for intelligently identifying *** signifcant features from UT data is essential for efcient defect ***,the hidden physics behind ML is unexplained,reducing the generalization capability and versatility of ML methods in *** this paper,a generally applicable ML framework based on the model interpretation strategy is proposed to improve the detection accuracy and computational efciency of ***,multi-domain features are extracted from the UT signals with signal processing techniques to construct an initial feature ***,a feature selection method based on model interpretable strategy(FS-MIS)is innovatively developed by integrating Shapley additive explanation(SHAP),flter method,embedded method and wrapper *** most efective ML model and the optimal feature subset with better correlation to the target defects are determined *** proposed framework is validated by identifying and locating side-drilled holes(SDHs)with 0.5λcentral distance and different *** ultrasonic array probe is adopted to acquire FMC datasets from several aluminum alloy specimens containing two SDHs by *** optimal feature subset selected by FS-MIS is set as the input of the chosen ML model to train and predict the times of arrival(ToAs)of the scattered waves emitted by adjacent *** experimental results demonstrate that the relative errors of the predicted ToAs are all below 3.67%with an average error of 0.25%,signifcantly improving the time resolution of UT *** this basis,the predicted ToAs are assigned to the corresponding original signals for decoupling overlapped pulse-echoes and reconstructing high-resolution FMC *** imaging resolution is enhanced to 0.5λby implementing the total focusing method(TFM).The relative errors of hole depths and central distance are no more than 0.51%and 3.57%,***

关键词： Ultrasonic testing Machine learning Feature extraction Feature selection Shapley additive explanation

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父母年龄和先天性唇(腭)裂患儿之间的关系

科学技术与工程 2024年第3期24卷 957-962页

作者：焦建军柴丛娜靳书滨石光马超邯郸市中心医院口腔颌面外科邯郸056000

为分析出唇(腭)裂疾病的发生概率和其父母年龄的关系,通过采用Logistic回归分析675例非综合征性唇(腭)裂患者,包括404例唇(腭)裂(cleft lip with/without cleft palate,CL±P),271例腭裂(isolated cleft palate,CP),并记录父母生育年龄... 详细信息

为分析出唇(腭)裂疾病的发生概率和其父母年龄的关系,通过采用Logistic回归分析675例非综合征性唇(腭)裂患者,包括404例唇(腭)裂(cleft lip with/without cleft palate,CL±P),271例腭裂(isolated cleft palate,CP),并记录父母生育年龄。根据裂隙的严重程度分为两组:唇(腭)裂(CL±P)及腭裂(CP)。单侧裂分为左侧裂及右侧裂。研究发现在唇(腭)裂(CL±P)中,父母双方年龄都大时,后代患唇(腭)裂(CL±P)的风险要比父母双方都年轻的高很多。在腭裂(CP)中,父母年龄大比父母年轻的后代更易患腭裂,但是无统计学意义。同时分析父母年龄和左右侧裂之间的关系,发现父母年龄和左右侧裂统计学无意义。随着父母年龄的增长,后代患唇(腭)裂的风险越大,进一步的分析表明,只有当父母双方的年龄都很高时,这种风险才会增加。

关键词：腭裂唇(腭)裂左右侧裂父母年龄回顾性研究

Catalytic Asymmetric Diastereodivergent Synthesis of 2-Alkenylindoles Bearing both Axial and Central Chirality

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Precision Chemistry 2024年第5期2卷 208-220页

作者： Shuang Yang Jia-Bo Huang Da-Hua Wang Ning-Yi Wang Yu-Yu Chen Xin-Yan Ke Hao Chen Shao-Fei Ni Yu-Chen Zhang Feng shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China Department of Chemistry Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Otolaryngology Xuzhou First People’s HospitalAffiliated Xuzhou Municipal Hospital of Xuzhou Medical UniversityXuzhou 221002China School of Petrochemical Engineering Changzhou UniversityChangzhou 213164China

The catalytic asymmetric diastereodivergent synthesis of axially chiral 2-alkenylindoles was established via chiral phosphoric acid-catalyzed addition reactions of C3-unsubstituted 2-alkenylindoles with o-hydroxybenzyl alcohols under different reaction *** this strategy,two series of 2-alkenylindoles bearing both axial and central chirality were synthesized in a diastereodivergent fashion with moderate to high yields and good stereoselectivities(up to 99%yield,95:5 er,>95:5 dr).Moreover,theoretical calculations were performed on the key transition states leading to different stereoisomers,which provided an in-depth understanding of the origin of the observed stereoselectivity and diastereodivergence of the products under different reaction *** importantly,these 2-alkenylindoles were utilized in asymmetric catalysis as chiral organocatalysts and in medicinal chemistry for evaluation of their cytotoxicity,which demonstrated their potential *** study has not only established the catalytic atroposelective synthesis of axially chiral 2-alkenylindoles,but also provided an efficient strategy for catalytic asymmetric diastereodivergent construction of indole-based scaffolds bearing both axial and central chirality.

关键词： 2-Alkenylindole Axial chirality Central chirality Diastereodivergent synthesis Chiral phosphoric acid

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雅鲁藏布江中游末端河段洲滩的时空变化特征

中国农村水利水电 2024年第2期 172-177,185页

作者：王珂赵庆绪史红玲王党伟杨靖中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100048 中国水利水电科学研究院水利部泥沙科学与北方河流治理重点实验室北京100048 雅江清洁能源科学技术研究(北京)有限公司北京100048

扎西绕登乡-派镇河段位于雅鲁藏布江中游末端,是中游宽谷最后一段典型的辫状河道,其洲滩演变对当地生态有重要的影响。基于1986-2022年21幅11月的Landsat遥感影像,提取并统计了雅鲁藏布江中游末端扎西绕登乡-派镇辫状河段内洲滩的特征参... 详细信息

扎西绕登乡-派镇河段位于雅鲁藏布江中游末端,是中游宽谷最后一段典型的辫状河道,其洲滩演变对当地生态有重要的影响。基于1986-2022年21幅11月的Landsat遥感影像,提取并统计了雅鲁藏布江中游末端扎西绕登乡-派镇辫状河段内洲滩的特征参数,并结合洲滩的形态指数和破碎度指数对洲滩的面积特征和平面形态变化进行了分析。结果表明:研究河段内80%的洲滩面积小于1 km^(2),且洲滩面积差异较大。1986-2022年间,洲滩的数量及洲滩面积整体变幅不大。雅鲁藏布江干流与尼洋河汇合口上游河段内洲滩分布更加细碎,主要为小面积心滩,且多年来洲滩的分布及形态变化较小。而下游河段内的洲滩分布相对集中,主要为大面积边滩,且多年来洲滩的分布及形态变化相对较大。

关键词：雅鲁藏布江辫状河道遥感影像洲滩特征

乙酸胍表面处理提高纯红光钙钛矿发光二极管性能

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发光学报 2024年第4期45卷 637-643页

作者：师明明江季张兴旺中国科学院半导体研究所半导体材料科学重点实验室北京100083 中国科学院大学材料科学与光电技术学院北京100049

金属卤化物钙钛矿材料由于具有优异的光电性质可被用于制作发光二极管,近年来备受关注。钙钛矿表面和钙钛矿/传输层的界面处存在大量的缺陷,严重影响器件的性能和稳定性,而对表/界面进行有效的钝化处理是减少界面缺陷、提升器件性能的... 详细信息

金属卤化物钙钛矿材料由于具有优异的光电性质可被用于制作发光二极管,近年来备受关注。钙钛矿表面和钙钛矿/传输层的界面处存在大量的缺陷,严重影响器件的性能和稳定性,而对表/界面进行有效的钝化处理是减少界面缺陷、提升器件性能的可行途径。本文报道了一种在萃取剂中添加乙酸胍的表面处理策略,可有效地减少钙钛矿层表面缺陷,改善薄膜形貌,进而将钙钛矿薄膜的荧光量子产率从64%提升到79%。基于乙酸胍表面处理的钙钛矿薄膜制备的发光二极管,最大效率可达11.66%,最大亮度达1285 cd·m^(-2),明显优于未处理的参考器件(6.69%,689 cd·m^(-2)),同时也展现出更好的稳定性。该研究提供了一种有效的钙钛矿表面处理策略,可以提高钙钛矿发光二极管的性能和稳定性。

关键词：钙钛矿发光二极管表面处理准二维缺陷钝化

城市土壤和地表灰尘重金属污染研究进展与展望

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环境科学 2024年第5期45卷 2926-2938页

作者：王晓雨刘恩峰杨祥梦王碧莲林锦阔颜梦霞毕世杰山东师范大学地理与环境学院济南250358

随着城市化和工业化的不断推进,城市土壤和地表灰尘重金属污染日趋严重,对城市环境和人类健康构成威胁,已成为国内外城市环境研究的热点问题.从重金属污染水平及其时空特征、污染源解析方法、生态和健康风险这3个主要方面,对国内外城市... 详细信息

随着城市化和工业化的不断推进,城市土壤和地表灰尘重金属污染日趋严重,对城市环境和人类健康构成威胁,已成为国内外城市环境研究的热点问题.从重金属污染水平及其时空特征、污染源解析方法、生态和健康风险这3个主要方面,对国内外城市土壤和地表灰尘重金属研究成果进行了梳理和归纳.分析了当前研究存在的不足,并对未来研究进行了展望,即研究土壤和地表灰尘重金属在不同条件下的相互影响机制,通过丰富验证方法加强重金属来源解析模型结果的可靠性研究,加强来源驱动下重金属化学形态差异和地表灰尘短期累积污染过程的研究,完善暴露参数并深入探究重金属的化学形态对其生态和健康风险的影响,以提高风险预测水平.

关键词：城市土壤和地表灰尘重金属时空变异来源分析风险评价

Protein Changes in Response to Pyrene Stress in Maize （Zea mays L.） Leaves

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Journal of Integrative Plant Biology 2007年第2期49卷 187-195页

作者： Sheng-You Xu Ying-Xu Chen wei-Xiang Wu Shao-Jian Zheng Sheng-Guo Xue shi-Ying Yang Yi-jin Peng Department of Environmental Engineering Zhejiang University Hangzhou 310029 China Department of Resource and Environment Huangshan University Huangshan 245000 China College of Environmental Science and Engineering Ocean University of China Qingdao 266003 China

Phytoremedlation is a relatively new approach to remove polycyclic aromatic hydrocarbons （PAHs） from the environment. When plants are grown under pyrene treatment, they respond by synthesizing a set of protective proteins. To learn more about protein changes in response to pyrene treatment, we extracted total proteins from the leaves of maize （Zea mays L.） 1 week after pyrene treatment. The proteins extracted were separated with twodimensional gel electrophoresis. In total, approximately 54 protein spots were found by comparing gels from treated and control groups. According to the Isoelectric point, molecular weight, and abundance of these protein spots, 20 pyrene-lnduced proteins were found to have changed abundance. Of these, 15 protein spots were Increased and five protein spots were newly appeared in pyrene-treated plant leaves. Six model upregulated protein spots of different molecular weights were excised from the gels and subjected to trypsin digestion followed by peptide separation using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Peptlde masses were used to search the matrix-science database for protein Identification. Two of the proteins were Identified on the basis of the homology of their peptide profiles with existing protein sequences as pyruvate orthophosphate diklnase and the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunlt. These proteins are Involved in the regulation of carbohydrate and energy metabolism. The present study gives new Insights into the pyrene stress response In maize leaves and demonstrates the power of the proteomlc approach in phytoremedlation of PAHs.

关键词： maize mass spectrometry proteomic pyrene stress.

D53 represses rice blast resistance by directly targeting phenylalanine ammonia lyases

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Journal of Integrative Plant Biology 2024年第9期66卷 1827-1830页

作者： Haitao Ye Qingqing Hou Haitao Lv Hui shi Duo Wang Yujie Chen Tangshuai Xu Mei Wang Min He Junjie Yin Xiang Lu Yongyan Tang Xiaobo Zhu Lijuan Zou Xuewei Chen Jiayang Li Bing Wang jing Wang State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Yazhouwan National Laboratory Sanya 572024China

Phytohormones play important roles in orchestrating plantimmune responses to pathogen ***(SLs),a group of carotenoid-derived phytohormones,modulate diverse biological processes in plants,including shoot branching,plant height,root architecture,leaf senescence,seed germination of parasitic plants,and symbiosis of arbuscular mycorrhizal fungi(Burger and Chory,2020).Recently,increasing evidence has indicated potential roles for SLs in regulating responses against biotic stresses,including defense responses against certain pathogenic fungi and bacteria in roots and leaves(Yi et al.,2023).

关键词： ammonia resistance branching

柠檬酸钠对碱激发粉煤灰滤液中钢筋的阻锈机制

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硅酸盐学报 2024年第2期52卷 603-613页

作者：周霄骋李曼施锦杰东南大学材料科学与工程学院江苏省土木工程材料重点实验室南京211189

碱激发粉煤灰是一种兼具低碳与环保优势的建筑材料,具备应用于海洋等氯盐侵蚀环境的潜力。作为一种典型的羧酸盐阻锈剂,柠檬酸钠可进一步保障碱激发粉煤灰中钢筋的耐蚀性。然而,柠檬酸钠对碱激发粉煤灰体系中钢筋的阻锈机制尚未明确。... 详细信息

碱激发粉煤灰是一种兼具低碳与环保优势的建筑材料,具备应用于海洋等氯盐侵蚀环境的潜力。作为一种典型的羧酸盐阻锈剂,柠檬酸钠可进一步保障碱激发粉煤灰中钢筋的耐蚀性。然而,柠檬酸钠对碱激发粉煤灰体系中钢筋的阻锈机制尚未明确。基于此,本研究通过电化学测试、钝化膜表征技术和腐蚀形貌及产物分析方法研究了氯盐侵蚀作用下柠檬酸钠对碱激发粉煤灰滤液中钢筋腐蚀行为的影响,并揭示了其阻锈机制。结果表明:虽然柠檬酸钠会一定程度上影响碱激发粉煤灰体系中钢筋钝化膜的稳定性,但其不仅能与氯离子产生竞争吸附效应,还能在钢筋表面形成吸附膜,从而有效提高钢筋的耐氯盐侵蚀能力。

关键词：碱激发粉煤灰钢筋柠檬酸钠钝化膜阻锈机制