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多级冷压合与高温蠕变应力松弛TC4钛合金微观组织演变机理研究

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塑性工程学报 2024年第10期31卷 109-115页

作者：刘彦绮安大勇李细锋陈军上海交通大学塑性成形技术与装备研究院上海200030

采用多级冷压合与高温蠕变应力松弛成形工艺制备TC4钛合金薄壁构件,研究了不同蠕变工艺参数对微观组织的影响规律。通过光学显微镜和电子背散射衍射技术分析了晶粒尺寸及取向、位错密度和裂纹萌生扩展。结果表明,在低塑性变形条件下,较... 详细信息

采用多级冷压合与高温蠕变应力松弛成形工艺制备TC4钛合金薄壁构件,研究了不同蠕变工艺参数对微观组织的影响规律。通过光学显微镜和电子背散射衍射技术分析了晶粒尺寸及取向、位错密度和裂纹萌生扩展。结果表明,在低塑性变形条件下,较高的蠕变温度可以促进α相晶粒长大。然而在大塑性变形条件下,微观组织受到蠕变温度和塑性变形共同影响。较高的温度加快位错回复,引起位错密度降低,从而减小了晶粒生长的驱动力,最终导致在较高的蠕变温度下α相晶粒反而更小。与600℃蠕变工艺相比,750℃蠕变后的TC4板材出现更多的裂纹,可能是β相粗化所致。

关键词： TC4钛合金蠕变成形微观组织应力松弛裂纹扩展

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Durable dual-state duplex Si-HfO_(2)with excellent oxi.ation and cracking resistance

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Journal of Advanced Ceramics 2024年第3期13卷 388-401页

作者： Lin Chen Jing-Chuan Luo Wen-Qi Yang Chang-Jiu Li Guan-jun Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China xi.an Aerospace Engine Company Limited in CASC Xi’an 710065China

The lifetime of Si bond coatings in environmental barrier coatings is constrained by phase-transition-induced cracking of the SiO_(2)*** this study,Si-HfO_(2)dual-state duplex composite materials are proposed to address this issue by partially forming HfSiO_(4)and minimizing the SiO_(2)*** as-prepared composite exhibited a structure comprising discrete HfO_(2)“bricks”embedded in a continuous Si“mortar”,while the oxi.ized state transformed into discrete HfSiO_(4)“bricks”within continuous thin SiO_(2)“mortars”.The results indicate that continuous thin SiO_(2)contributes to reducing the oxi.ation rate to a level comparable to that of pure Si,and discrete HfSiO_(4)particles aid in relieving phase transition-induced stress and inhibiting crack propagation,thereby enhancing oxi.ation and cracking resistance ***,the composite with 20 mol%HfO_(2)and a mean particle size of~500 nm at 1370℃exhibited a service lifetime 10 times greater than that of pure *** research provides valuable insights for designing Si-based bond coatings with improved service lifetime.

关键词： oxi.ation environmental barrier coatings(EBCs) phase transition cracking bond coatings

Recent progress on fabrication, spectroscopy properties, and device applications in Sn-doped CdS micro-nano structures

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Journal of Semiconductors 2024年第9期45卷 7-27页

作者： Bo Cao Ye Tian Huan Fei Wen Hao Guo xi.oyu Wu Liangjie Li Zhenrong Zhang Lai Liu Qiang Zhu jun Tang jun Liu State Key Laboratory of Dynamic Measurement Technology School of Semiconductors and PhysicsNorth University of ChinaTaiyuan 030051China Shanxi.Province Key Laboratory of Quantum Sensing and Precision Measurement North University of ChinaTaiyuan 030051China School of Instrument Science and Technology Xi'an Jiaotong UniversityXi'an 710049China

One-dimensional semiconductor materials possess excellent photoelectric properties and potential for the construction of integrated nanodevices. Among them, Sn-doped CdS has different micro-nano structures, including nanoribbons,nanowires, comb-like structures, and superlattices, with rich optical microcavity modes, excellent optical properties, and a wide range of application fields. This article reviews the research progress of various micrometer structures of Sn-doped CdS, systematically elaborates the effects of different growth conditions on the preparation of Sn-doped CdS micro-nano structures, as well as the spectral characteristics of these structures and their potential applications in certain fields. With the continuous progress of nanotechnology, it is expected that Sn-doped CdS micro-nano structures will achieve more breakthroughs in the field of optoelectronics and form cross-integration with other fields, jointly promoting scientific, technological, and social development.

关键词： Sn-doped CdS micro-nano structure superlattices optical microcavity

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生态困境的理性论根源及其消解

自然辩证法研究 2024年第7期40卷 39-46页

作者：赵若玺赵建军中国国土勘测规划院北京100035 中共中央党校/国家行政学院北京100091

“无限理性”和“有限理性”作为经济学、决策理论及心理学等领域的重要概念,影响已远超其提出的特定视域。从更广义的哲学社会科学视角来看,无限理性表征着理性主义至上的价值观念和实践原则,这种强势理性观一直塑造着人类解释世界对... 详细信息

“无限理性”和“有限理性”作为经济学、决策理论及心理学等领域的重要概念,影响已远超其提出的特定视域。从更广义的哲学社会科学视角来看,无限理性表征着理性主义至上的价值观念和实践原则,这种强势理性观一直塑造着人类解释世界对待自然的狂妄姿态,是造成人与自然冲突引发生态困境的内在根源。有限理性则在批判反思前者的基础上追问人类理性活动的限度,重塑着我们理解对待自然的方式。有限理性的现实建构将为生态困境的消解,实现人与自然和谐共生提供有益的价值遵循和实践进路。

关键词：理性无限理性有限理性生态困境

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发展长江水利新质生产力的几点思考

长江科学院院报 2024年第9期41卷 1-7页

作者：许全喜许继军长江科学院武汉430010

发展水利新质生产力,是破解长江新老水问题、提升流域安全保障能力、推动长江经济带高质量发展的内在要求和重要着力点。结合长江治理保护新阶段特征和面临的挑战,基于新质生产力概念,从生态水利科技创新、生产要素数字智能化、产业绿... 详细信息

发展水利新质生产力,是破解长江新老水问题、提升流域安全保障能力、推动长江经济带高质量发展的内在要求和重要着力点。结合长江治理保护新阶段特征和面临的挑战,基于新质生产力概念,从生态水利科技创新、生产要素数字智能化、产业绿色转型升级等方面,探讨长江水利新质生产力的形成路径和原则要求,并提出加强近自然水工程、数字孪生、节水减污降碳、流域现代管理等方面的科技创新建议,以促进长江生态化、智慧化、绿色化和现代化发展。

关键词：新质生产力长江流域水利现代化高质量发展科技创新

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基于聚类算法和图神经网络的短时交通流预测

吉林大学学报（工学版） 2024年第6期54卷 1593-1600页

作者：张玺君余光杰崔勇尚继洋兰州理工大学计算机与通信学院兰州730050

针对现有预测模型未充分利用交通流数据时空相关性的问题,本文提出了一种深度学习模型,将聚类算法、图神经网络(GNN)和门控循环单元(GRU)相结合。首先,利用聚类算法将预处理后的数据划分为不同类型的流量模式;其次,采用GNN提取复杂路网... 详细信息

针对现有预测模型未充分利用交通流数据时空相关性的问题,本文提出了一种深度学习模型,将聚类算法、图神经网络(GNN)和门控循环单元(GRU)相结合。首先,利用聚类算法将预处理后的数据划分为不同类型的流量模式;其次,采用GNN提取复杂路网交通流的空间相关性,结合道路的皮尔逊相关性分析和节点的局部聚类系数,挖掘潜在的节点连接关系;再次,使用GRU提取交通流数据之间的时间相关性,通过自注意力机制捕获数据之间的相互依赖关系;最后,通过残差连接将GRU和GNN的输出与原始输入结合,经过全连接层得出最终的预测结果。多组实验结果证明,本文提出的模型预测精度优于其他基线模型及对比的模型。

关键词：交通流预测图神经网络聚类算法门控循环单元皮尔逊相关系数局部聚类系数

The energy response of LaBr_(3)(Ce),LaBr_(3)(Ce,Sr),and NaI(Tl)crystals for GECAM

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Nuclear Science and Techniques 2024年第2期35卷 110-122页

作者： Pei-Yi Feng xi.Lei Sun Zheng-Hua An Yong Deng Cheng-Er Wang Huang Jiang jun-Jie Li Da-Li Zhang xi.-Qiao Li Shao-Lin xi.ng Chao Zheng Ke Gong Sheng Yang xi.o-Jing Liu Min Gao xi.ng-Yang Wen Ya-Qing liu Yan-Bing Xu xi.o-Yun Zhao Jia-Cong Liu Fan Zhang Hong Lu Particle and Astrophysics Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Experimental Physics Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Nuclear Science and Technology University of South ChinaHengyang 421001China National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.and General Research Institute for Nonferrous MetalsBeijing 100088China

The GECAM series of satellites utilizes LaBr_(3)(Ce),LaBr_(3)(Ce,Sr),and NaI(Tl)crystals as sensitive materials for gamma-ray detectors(GRDs).To investigate the nonlinearity in the detection of low-energy gamma rays and address the errors in the calibration of the E-C relationship,comprehensive tests and comparative studies of the three aforementioned crystals were conducted using Compton electrons,radioactive sources,and mono-energetic *** nonlinearity test results of the Compton electrons and X-rays demonstrated substantial differences,with all three crystals presenting a higher nonlinearity for X/-rays than for Compton *** the LaBr_(3)(Ce)and LaBr_(3)(Ce,Sr)crystals having higher absolute light yields,they exhibited a noticeable nonlinear decrease in the light yield,especially at energies below 400 *** NaI(Tl)crystal demonstrated an"excess"light output in the 6-200 keV range,reaching a maxi.um"excess"of 9.2%at 30 keV in the X-ray testing and up to 15.5%at 14 keV during Compton electron testing,indicating a significant advantage in the detection of low-energy gamma ***,we explored the underlying causes of the observed nonlinearity in these *** study not only elucidates the detector responses of GECAM,but also initiates a comprehensive investigation of the nonlinearity of domestically produced lanthanum bromide and sodium iodide crystals.

关键词： LaBr_(3)(Ce)detector LaBr_(3)(Ce,Sr)detector NaI(Tl)detector GECAM Energy response Light yield nonlinearity

Colorectal Cancer Segmentation Algorithm Based on Deep Features from Enhanced CT Images

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Computers, Materials & Continua 2024年第8期80卷 2495-2510页

作者： Shi Qiu Hongbing Lu jun Shu Ting Liang Tao Zhou School of Biomedical Engineering Fourth Military Medical UniversityXi’an710119China Department of Radiology Xijing HospitalFourth Military Medical UniversityXi’an710032China Department of Radiology The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710061China School of Computer Science and Engineering North Minzu UniversityYinchuan750030China

Colorectal cancer,a malignant lesion of the intestines,significantly affects human health and life,emphasizing the necessity of early detection and *** segmentation of colorectal cancer regions directly impacts subsequent staging,treatment methods,and prognostic *** colonoscopy is an effective method for detecting colorectal cancer,its data collection approach can cause patient *** address this,current research utilizes Computed Tomography(CT)imaging;however,conventional CT images only capture transient states,lacking sufficient representational capability to precisely locate colorectal *** study utilizes enhanced CT images,constructing a deep feature network from the arterial,portal venous,and delay phases to simulate the physician’s diagnostic process and achieve accurate cancer *** innovations include:1)Utilizing portal venous phase CT images to introduce a context-aware multi-scale aggregation module for preliminary shape extraction of colorectal cancer.2)Building an image sequence based on arterial and delay phases,transforming the cancer segmentation issue into an anomaly detection problem,establishing a pixel-pairing strategy,and proposing a colorectal cancer segmentation algorithm using a Siamese *** with 84 clinical cases of colorectal cancer enhanced CT data demonstrated an Area Overlap Measure of 0.90,significantly better than Fully Convolutional Networks(FCNs)at *** research will explore the relationship between conventional and enhanced CT to further reduce segmentation time and improve accuracy.

关键词： Colorectal cancer enhanced CT multi-scale siamese network segmentation

血清铁蛋白、叶酸、维生素B_(12)在硼替佐米联合化疗治疗多发性骨髓瘤中的价值研究

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中国实验血液学杂志 2024年第5期32卷 1427-1431页

作者：王丽发朱熙君宣城市人民医院血液内科安徽宣城242000

目的:探讨血清铁蛋白、叶酸、维生素B_(12)在硼替佐米联合化疗治疗多发性骨髓瘤(MM)中的价值。方法:回顾性分析宣城市人民医院在2020年1月至2022年8月收治的40例MM患者和同期40例血液科门诊患者的临床资料,全部MM患者采用硼替佐米联合... 详细信息

目的:探讨血清铁蛋白、叶酸、维生素B_(12)在硼替佐米联合化疗治疗多发性骨髓瘤(MM)中的价值。方法:回顾性分析宣城市人民医院在2020年1月至2022年8月收治的40例MM患者和同期40例血液科门诊患者的临床资料,全部MM患者采用硼替佐米联合化疗治疗。运用ROC曲线分析血清铁蛋白、叶酸、维生素B_(12)对MM的诊断效能。比较MM患者治疗前后血清铁蛋白、叶酸、维生素B_(12)水平的变化。根据血清铁蛋白、叶酸、维生素B_(12)水平的均值将患者分为高低表达组,对比分析组间患者的生存情况。结果:MM患者治疗前的血清铁蛋白、维生素B_(12)水平明显高于对照组,叶酸明显低于对照组(均P<0.001)。铁蛋白、叶酸、维生素B_(12)诊断MM患者的AUC分别为0.928、0.843、0.867,特异度分别为100%、67.50%、72.50%,敏感度分别为80.00%、95.00%、87.50%。经4个化疗周期后,40例MM患者CR 9例,VGPR 19例,PR 6例,SD 4例,PD 2例。CR组治疗后的铁蛋白、维生素B_(12)水平较治疗前降低,叶酸较治疗前升高(均P<0.05)。铁蛋白、维生素B_(12)低表达组患者的OS均明显优于高表达组,叶酸高表达组患者的OS明显优于低表达组(均P<0.01)。Cox多因素回归分析结果显示,铁蛋白是MM患者预后的独立影响因素(HR=8.850,95%CI:2.267-34.553,P=0.002)。结论:血清铁蛋白、叶酸、维生素B_(12)对MM的诊断和疗效评估均具有一定辅助价值,其中铁蛋白是MM预后的独立影响因素。

关键词：铁蛋白叶酸维生素B_(12) 多发性骨髓瘤