检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 904-914页

作者： Keke Lu Congjiang Zhang Xiaotan Yuan Hongbin Yu Weili ren Biao Ding Haibiao Lu Yunbo Zhong Zuosheng Lei Hui Wang Qiuliang Wang Peter KLiaw xuezhi Qin Lanzhang Zhou State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgyShanghai UniversityShanghai 200444China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The magnetic field is an effective means to control the solidification structure and the defects of metal and semiconductor crystals.This work investigates the effects of Cusp magnetic field(CMF)and longitudinal magnetic field(LMF)on the stray-crystal formation in the platform regions during the directional solidification of single-crystal superalloy with the different cross section sizes.The application of CMF reduces the formation of platform stray-crystal,while LMF increases its generation.As the platform size increases,the stray-crystal ratio increases regardless of whether the magnetic fields are applied or not,the effectiveness of CMF increases,while that of LMF decreases.The reason that the effects of CMF and LMF on the platform stray-crystal formation could be attributed to the change of flow structure from the distribution characteristics of the thermoelectric magnetic force and the magnetic damping force near the liquid-solid interface.

关键词： Stray-crystal Magnetic field Single-crystal superalloy Cross section change Directional solidification

Material decomposition of spectral CT images via attention-based global convolutional generative adversarial network

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2023年第3期34卷 143-153页

作者： Xiaodong Guo Peng He Xiaojie Lv xuezhi ren Yonghui Li Yuanfeng Liu Xiaohua Lei Peng Feng Hongming Shan The Key Lab of Optoelectronic Technology and Systems of the Education Ministry of China Chongqing UniversityChongqing 400044China Department of Vascular and Endovascular Surgery First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450003China Institute of Science and Technology for Brain-inspired Intelligence and MOE Frontiers Center for Brain Science Fudan UniversityShanghai 200433China Shanghai Center for Brain Science and Brain-Inspired Technology Shanghai 200031China

Spectral computed tomography(CT)based on photon counting detectors can resolve the energy of every single photon interacting with the sensor layer and be used to analyze material attenuation information under different energy ranges,which can be helpful for material decomposition studies.However,there is a considerable amount of inherent quantum noise in narrow energy bins,resulting in a low signal-to-noise ratio,which can consequently affect the material decomposition performance in the image domain.Deep learning technology is currently widely used in medical image segmentation,denoising,and recognition.In order to improve the results of material decomposition,we propose an attention-based global convolutional generative adversarial network(AGC-GAN)to decompose different materials for spectral CT.Specifically,our network is a global convolutional neural network based on an attention mechanism that is combined with a generative adversarial network.The global convolutional network based on the attention mechanism is used as the generator,and a patchGAN discriminant network is used as the discriminator.Meanwhile,a clinical spectral CT image dataset is used to verify the feasibility of our proposed approach.Extensive experimental results demonstrate that AGC-GAN achieves a better material decomposition performance than vanilla U-Net,fully convolutional network,and fully convolutional denseNet.Remarkably,the mean intersection over union,structural similarity,mean precision,PAcc,and mean F1-score of our method reach up to 87.31%,94.83%,93.22%,97.39%,and 93.05%,respectively.

关键词： Photon-counting CT Material decomposition Attention mechanism GAN

改性纳米Bi_(2)O_(3)/Eu_(2)O_(3)/EPVC基X射线屏蔽材料的制备及性能研究

在线全文

学校读者我要写书评

暂无评论

化工新型材料 2024年第2期52卷 104-109页

作者：赵娇任翼戴学志晏敏皓西南科技大学环境友好能源材料国家重点实验室绵阳621010 西南科技大学材料与化学学院绵阳621010 苏州子涵科技有限公司苏州215011

针对当前辐射防护产品日益增长的需求,研发出一种新型X射线屏蔽材料。以乙烯基三甲氧基硅烷(A-171)对纳米氧化铋(Bi_(2)O_(3))、纳米氧化铕(Eu_(2)O_(3))进行表面改性,并作为填料填充至PVC糊树脂(EPVC)基体中制备得到改性纳米复合材料Bi... 详细信息

针对当前辐射防护产品日益增长的需求,研发出一种新型X射线屏蔽材料。以乙烯基三甲氧基硅烷(A-171)对纳米氧化铋(Bi_(2)O_(3))、纳米氧化铕(Eu_(2)O_(3))进行表面改性,并作为填料填充至PVC糊树脂(EPVC)基体中制备得到改性纳米复合材料Bi_(2)O_(3)/Eu_(2)O_(3)/EPVC(简称为BEP)。采用X射线衍射仪(XRD)、傅里叶红外光谱(FT-IR)对改性前后的纳米颗粒进行表征。采用模拟计算与实验相结合的方式,通过WinXcom模拟Bi_(2)O_(3)、Eu_(2)O_(3)对X射线的屏蔽能力并计算Bi_(2)O_(3)、Eu_(2)O_(3)的最佳质量配比,通过热重分析、力学性能测试、断面扫描及X射线屏蔽性能测试研究了改性纳米填料含量对BEP性能的影响。结果表明:改性纳米Bi_(2)O_(3)、Eu_(2)O_(3)质量比为1∶1时BEP同时具备对中、低能X射线有较好的屏蔽性能,且填料基体质量比为5∶2,厚度为4mm时能达到同等厚度下最佳的X射线屏蔽效果。实际应用中,填料与EPVC基体的质量比为5∶1时具有最佳拉伸性能。BEP材料环境友好、无生物毒性,可用来替代含铅材料在X射线屏蔽中的部分功能。

关键词： X射线屏蔽辐射防护氧化铋氧化铕

用于全氟辛烷磺酸盐检测的“开启”式荧光探针

在线全文

学校读者我要写书评

暂无评论

发光学报 2024年第5期45卷 846-852页

作者：宋学智宋一凡 WONG Shiqing 张燕宁刘俊杰王婕王丽娜任相魁天津大学化工学院天津市膜科学与海水淡化技术重点实验室天津300350 天津大学浙江研究院浙江宁波315201 河北师范大学生命科学学院河北石家庄050024

全氟辛烷磺酸盐(Perfluorooctane sulfonate,PFOS)是一种持久有机污染物,具有生物毒性、高稳定性、存在范围广的特点,严重威胁人类健康安全。因此,对PFOS的检测具有重要意义。本文通过简单的合成制备了一种四苯基乙烯衍生物(TPE-py)用... 详细信息

全氟辛烷磺酸盐(Perfluorooctane sulfonate,PFOS)是一种持久有机污染物,具有生物毒性、高稳定性、存在范围广的特点,严重威胁人类健康安全。因此,对PFOS的检测具有重要意义。本文通过简单的合成制备了一种四苯基乙烯衍生物(TPE-py)用于检测PFOS。通过核磁共振谱图、荧光光谱以及紫外-可见吸收光谱等方法对其分子结构、光物理性质、检测效果和传感机理进行了研究。实验结果表明,基于静电相互作用和聚集诱导发光性质,TPE-py可实现对PFOS“开启”式的快速定量检测,检测限为0.11μmol/L。

关键词：四苯基乙烯聚集诱导发光全氟辛烷磺酸盐

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

互感式自调零正交涡流传感器设计与研究

仪表技术与传感器 2024年第5期 106-112页

作者：任学志杨明金亚曦曹军帅杨正好徐笑娟国网安徽省电力有限公司马鞍山供电公司安徽工业大学电气与信息工程学院

针对涡流检测过程中传感器易发生提离和摇晃造成缺陷误判和漏检的问题,利用电磁场理论,研究了双Pancake式线圈之间的零互感特性,提出了一种互感式正交自动调零涡流传感器;同时搭建了基于六轴机器人引导的涡流检测系统,对铝筒体轴向和环... 详细信息

针对涡流检测过程中传感器易发生提离和摇晃造成缺陷误判和漏检的问题,利用电磁场理论,研究了双Pancake式线圈之间的零互感特性,提出了一种互感式正交自动调零涡流传感器;同时搭建了基于六轴机器人引导的涡流检测系统,对铝筒体轴向和环向表面裂纹进行了相关实验研究。结果表明:相比同轴型涡流传感器,该传感器在筒体缺陷检测过程中对提离和摇晃的抑制力更佳,通过面内旋转其激励线圈至0°和90°,能够清晰地识别出铝筒体轴向和环向的表面裂纹。该传感器在不依赖高精度姿态校准前提下,有效解决了提离和摇晃造成缺陷误判和漏检的问题,对导电结构外场原位检测具有重要的应用意义。

关键词：涡流检测提离效应正交涡流传感器零互感特性铝筒体裂纹检测

中医醒脑开窍针灸法对脑卒中偏瘫患者康复期肢体功能恢复进程的影响

在线全文

学校读者我要写书评

暂无评论

医学临床研究 2024年第1期41卷 58-61页

作者：郭宝苏醒任雪芝袁晓东王茹渭南市中心医院神经内科陕西渭南714000

【目的】探讨中医醒脑开窍针灸法对脑卒中偏瘫患者康复期肢体功能恢复进程的影响。【方法】102例脑卒中后偏瘫患者,随机分为两组,每组51例。对照组患者行常规康复训练,观察组在此基础上另行中医醒脑开窍针灸治疗,治疗4周后,比较两组患... 详细信息

【目的】探讨中医醒脑开窍针灸法对脑卒中偏瘫患者康复期肢体功能恢复进程的影响。【方法】102例脑卒中后偏瘫患者,随机分为两组,每组51例。对照组患者行常规康复训练,观察组在此基础上另行中医醒脑开窍针灸治疗,治疗4周后,比较两组患者的临床疗效、中医证候积分、Brunnstrom分期、运动功能[Fugl-Meyer运动功能(FMA)评定量表、Berg平衡量表(BBS)]、神经功能和日常生活活动能力[美国国立卫生研究院卒中量表(NIHSS)、改良Rankin量表(mRS)]。【结果】观察组总有效率高于对照组(P<0.05)。治疗后,两组患者的舌质暗红、爪甲紫暗、面色晦暗、偏身麻木、手足肿胀、口唇及齿龈暗等证候评分较治疗前均下降(P<0.05),且观察组各项评分低于对照组(P<0.05)。观察组治疗后上肢、下肢、手Brunnstrom分期Ⅲ期占比高于对照组(P<0.05)。两组治疗后上肢、下肢FMA评分及BBS评分高于治疗前(P<0.05),且观察组治疗后上肢、下肢FMA评分及BBS评分高于对照组(P<0.05)。两组治疗后NIHSS评分、mRS评分较治疗前均下降(P<0.05),且观察组治疗后NIHSS评分、mRS评分低于对照组(P<0.05)。【结论】醒脑开窍针灸法能有效改善脑卒中后康复期偏瘫患者的中医证候评分,提高肢体Brunnstrom分期和肢体运动能力,改善神经功能,综合疗效较好,建议推广应用。

关键词：卒中/并发症偏瘫/并发症卒中/针灸疗法偏瘫/针灸疗法运动障碍/康复

Enhanced recycling performance of bimetallic Ir-Re/SiO_(2) catalyst by amberlyst-15 for glycerol hydrogenolysis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2022年第5期35卷 171-181页

作者： Xin ren Li Leng Yueqiang Cao Jing Zhang xuezhi Duan Xueqing Gong Jinghong Zhou Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Institute of Industrial CatalysisEast China University of Science and TechnologyShanghai 200237China

Recycling performance of heterogeneous catalysts is of crucial importance especially for a batch reaction system.In this work,we demonstrate a strategy for enhancing recycling performance of Ir-Re/SiO_(2) catalyst synergized with amberlyst-15 in glycerol hydrogenolysis to produce 1,3-propanediol.Comprehensive characterization results reveal that the Re sites in the Ir-Re/SiO_(2) catalyst undergo irreversible segregation and oxidation.These hinder the formation of active ReAOH species and thus contribute to a complete and irreversible deactivation.However,the introduction of amberlyst-15 into the reactant mixture can restrain the oxidation process of Re sites and favor the formation of ReAOH species,and thus significantly enhance the catalytic recycling performance.The results demonstrated here could guide the development of excellent bimetallic catalysts with the desirable recycling performances for the reaction.

关键词： Glycerol hydrogenolysis Ir-Re/SiO_(2)catalyst Deactivation mechanism Recycling performance Amberlyst-15 promoter

在线全文

学校读者我要写书评

暂无评论

高温与冷却方式对纤维混凝土影响研究

新型建筑材料 2024年第1期51卷 25-28页

作者：孙传武王学志任莉莉冯思源辛明贺晶晶辽宁工业大学土木建筑工程学院辽宁锦州121001 辽宁铁道职业技术学院铁道工程学院辽宁锦州121001 中国电建集团西北勘测设计研究院有限公司陕西西安710065

研究了高温对玻璃-聚丙烯混杂纤维混凝土的影响,对比了不同的冷却方式对混凝土强度的影响,基于试验结果分析了高温损伤机理和纤维增强机理。研究表明:喷水冷却对混凝土强度损伤大,玻璃纤维和聚丙烯纤维混掺掺量分别为0.4%和0.1%时,能够... 详细信息

研究了高温对玻璃-聚丙烯混杂纤维混凝土的影响,对比了不同的冷却方式对混凝土强度的影响,基于试验结果分析了高温损伤机理和纤维增强机理。研究表明:喷水冷却对混凝土强度损伤大,玻璃纤维和聚丙烯纤维混掺掺量分别为0.4%和0.1%时,能够显著提高混凝土的耐火性能,在400℃下,自然冷却时,抗压和抗折强度较基准组分别提高了15.3%和30.9%;喷水冷却时,抗压和抗折强度较基准组分别提高了21.3%和30.3%。

关键词：高温冷却方式玻璃纤维聚丙烯纤维混凝土

Nucleon momentum distribution of 56Fe from the axially deformed relativistic mean-field model with nucleon-nucleon correlations

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2021年第9期64卷 29-40页

作者： xuezhi Wang Qinglin Niu Jinjuan Zhang Mengjiao Lyu Jian Liu Chang Xu Zhongzhou ren College of Science China University of Petroleum(East China)Qingdao 266580China College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590China College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016China Department of Physics Nanjing UniversityNanjing 210093China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

Nucleon momentum distribution(NMD), particularly its high-momentum components, is essential for understanding the nucleonnucleon(NN) correlations in nuclei. Herein, we develop the studies of NMD of 56Fe from the axially deformed relativistic mean-field(RMF) model. Moreover, we introduce the effects of NN correlation into the RMF model from phenomenological models basing on deuteron and nuclear matter. For the region k kF, the high-momentum components of the RMF model are modified by the effects of NN correlation, which agree with the experimental data. Comparing the NMD of relativistic and non-relativistic mean-field models, the relativistic effects on nuclear structures in momentum space are analyzed. Finally, by analogizing the tensor correlations in deuteron and Jastrow-type correlations in nuclear matter, the behaviors and contributions of NN correlations in 56Fe are further analyzed, which helps clarify the effects of the tensor force on the NMD of heavy nuclei.

关键词： nucleon momentum distribution deformed relativistic mean-field model nucleon-nucleon correlations

The Arabidopsis catalase triple mutant reveals important roles of catalases and peroxisome-derived signaling in plant development

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2018年第7期60卷 591-607页

作者： Tong Su Pingping Wang Huijuan Li Yiwu Zhao Yao Lu Peng Dai Tianqi ren Xiaofeng Wang xuezhi Li Qun Shao Dazhong Zhao Yanxiu Zhao Changle Ma Shandong Provincial Key Laboratory of Plant Stress College of Life Sciences Shandong Normal University Department of Biological Sciences University of Wisconsin-Milwaukee

Hydrogen peroxide （H2O2） is generated in many metabolic processes. As a signaling molecule, H2O2 plays important roles in plant growth and development, as well as environmental stress response. In Arabidopsis, there are three catalase genes, CAT1, CAT2, and CAT3. The encoded catalases are predominately peroxisomal pro- teins and are critical for scavenging H2O2. Since CAT1 and CAT3 are linked on chromosome 1, it has been almost impossible to generate cat1/3 and cats1/2/3 mutants by traditional genetic tools. In this study, we constructed cat1/3 double mutants and cat1/22/3 triple mutants by CRISPR/Cas9 to investigate the role of catalases. The cat1/ 2/3 triple mutants displayed severe redox disturbance and growth defects under physiological conditionscompared with wild-type and the cat2/3 double mutants. Transcriptome analysis showed a more profound tran- scriptional response in the cat1/2/3 triple mutants compared to the cat2/3 mutants. These differentially expressed genes are involved in plant growth regulation as well as abiotic and biotic stress responses. In addition, expression of OXI1 （OXIDATIVE SIGNAL INDUCIBLE 1） and several MAPK cascade genes were changed dramatically in the catalase triple mutant, suggesting that H2O2 produced in peroxisomes could serve as a peroxisomal retrograde signal.

关键词： Cong-Ming Lu Institute of Botany CAS China