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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi Yi Wan yongqiang zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Improving strength-ductility synchronously of Electron beam welded Ti600/Ti2AlNb joint through isothermal forging

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Progress in Natural Science:Materials International 2024年第3期34卷 532-539页

作者： yongqiang zhang Xiangyi Xue Guoming Zheng Jingli zhang Huiming Li Shewei Xin State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an Qin Ti Intelligent Manufacturing Technologies Co.Ltd. Northwest Institute for Nonferrous Metal Research Xi'an University of Science and Technology Avic Xi'an Aircraft Industry Group Company Ltd.

Different alloys can be flexibly combined to meet the performance needs of different parts of the compressor disc by welding process. However, achieving a good combination of dissimilar alloys with different mechanical properties has always been a research difficulty. In this work, a Ti600/Ti2AlNb joint was fabricated through electron beam welding and an isothermal forging was used to optimized its microstructure and mechanical performance. The isothermal forging process increases the ultimate tensile strength（UST） and yield strength（YS）of the Ti600/Ti2AlNb joint by ～18 %, while ～2.5 times the ductility. It is indicated that before forging, the Ti600/Ti2AlNb joint exhibits a much lower strength than that of Ti600 matrix, whereas the opposite is true after isothermal forging. The isothermal forging broken the coarse columnar grains of Ti600/Ti2AlNb joint and render to an equiaxed B2 structure in which the acicular α2and O phase are precipitated, resulting a synchronous enhancement of strength and ductility. This work may pave an effective routine for improving the comprehensive mechanical properties of dissimilar metal welding joint.

关键词： Electron beam welding Isothermal forging Mechanical performance Ti600/Ti2AlNb joint

Tumor immunological phenotype-derived gene classification predicts prognosis,treatment response,and drug candidates in ovarian cancer

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Genes & Diseases 2024年第5期11卷 94-97页

作者： Chengbin Guo Yuqin Tang Zhihai Liu a Chuanliang Chen Xun Hu yongqiang zhang Guangzhou Women and Children’s Medical Center Guangzhou Medical UniversityGuangzhouGuangdong 510623China Clinical Bioinformatics Experimental Center Henan Provincial People’s HospitalPeople’s Hospital of Zhengzhou UniversityZhengzhouHenan 450003China School of Pharmacy Macao University of Science and TechnologyTaipaMacao 999078China Clinical Research Center The Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310003China Biorepository State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuan 610041China West China School of Medicine West China HospitalSichuan UniversityChengduSichuan 610041China

The high recurrence and low responsiveness to immunotherapy make ovarian cancer(OC)the most lethal gynecological *** microenvironment is critical in risk stratification and the discovery of molecular *** developed a prognostic classification for OC,which could also predict the prognosis of other gynecological cancers including breast cancer,endometrial cancer,and cervical *** mutation,hallmark pathways,and immune landscapes were *** analysis of immune checkpoints and multiple immune signatures revealed the low-risk group responds better to immune checkpoint inhibitors,which was validated by an external immunotherapeutic cohort(IMvigor210).Singlecell RNA sequencing(scRNA-seq)confirmed the high expression of SERPINB1 and SERPINB9 in dendritic cells,and AlphaFold2 was used to infer their 3D protein *** molecular compounds binding to SERPINB1/SERPINB9 were predicted by virtual screening.

关键词： prognosis cancer treatment

Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis

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Neural Regeneration Research 2024年第3期19卷 642-649页

作者： Xiuling Tang Tao Yan Saiying Wang Qingqing Liu Qi Yang yongqiang zhang Yujiao Li Yumei Wu Shuibing Liu Yulong Ma Le Yang Precision Pharmacy&Drug Development Center Department of PharmacyTangdu HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Clinical Pharmacy Jinling HospitalMedical School of Nanjing UniversityNanjingJiangsu ProvinceChina Department of Pharmacology School of PharmacyAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Anesthesiology The First Medical Center of Chinese PLA General HospitalBeijingChina Department of Anatomy Histology and Embryology and K.K.Leung Brain Research CentreAir Force Medical UniversityXi’anShaanxi ProvinceChina

β-Sitosterol is a type of phytosterol that occurs naturally in *** studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic *** we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced *** investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic *** addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its *** conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways.

关键词： apoptosis blood-brain barrier β-sitosterol cerebral ischemia/reperfusion injury cholesterol overload cholesterol transport endoplasmic reticulum stress ischemic stroke molecular docking NPC1L1

Few-Shot Named Entity Recognition with the Integration of Spatial Features

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Wuhan University Journal of Natural Sciences 2024年第2期29卷 125-133页

作者： LIU Zhiwei HUANG Bo XIA Chunming XIONG Yujie ZANG Zhensen zhang yongqiang College of Electrical and Electronic Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Zhongyu Academy of Industrial Internet Shanghai 201620China AIoT Manufacturing Solutions Technology Co. Ltd.Hefei 230000AnhuiChina

The few-shot named entity recognition(NER)task aims to train a robust model in the source domain and transfer it to the target domain with very few annotated ***,some approaches rely on the prototypical network for ***,these approaches often overlook the spatial relations in the span boundary matrix because entity words tend to depend more on adjacent *** propose using a multidimensional convolution module to address this limitation to capture short-distance spatial ***,we uti-lize an improved prototypical network and assign different weights to different samples that belong to the same class,thereby enhancing the performance of the few-shot NER *** experimental analysis demonstrates that our approach has significantly improved over baseline models across multiple datasets.

关键词： named entity recognition prototypical network spatial relation multidimensional convolution

不同惰性调控离子对钕掺杂氟磷酸锶透明陶瓷微观结构和光谱性能的影响

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硅酸盐学报 2024年第3期52卷 899-905页

作者：张永强梅炳初武汉理工大学材料复合新技术国家重点实验室武汉430070

采用传统热压烧结法制备了不同惰性调控离子掺杂的Nd:Sr_(5)(PO_(4))_(3)F (Nd:S-FAP)透明陶瓷,研究了陶瓷相组成对微观结构、光谱性能的影响规律。结果表明:所制备的S-FAP透明陶瓷为纯相,无杂相生成,晶格常数随着掺杂离子与Sr离子半径... 详细信息

采用传统热压烧结法制备了不同惰性调控离子掺杂的Nd:Sr_(5)(PO_(4))_(3)F (Nd:S-FAP)透明陶瓷,研究了陶瓷相组成对微观结构、光谱性能的影响规律。结果表明:所制备的S-FAP透明陶瓷为纯相,无杂相生成,晶格常数随着掺杂离子与Sr离子半径差异的增大而减小;所制备的样品在1μm处透过率为70%,在500 nm处为40%;掺入惰性调控离子后,Nd:S-FAP透明陶瓷的发射强度及荧光寿命存在增大的趋势,其中掺入Y离子后调控作用更为有效。通过共掺惰性离子,打破了钕离子在S-FAP基质材料中的团簇现象,提升了钕离子的发光性能。

关键词：钕掺杂氟磷酸锶透明陶瓷微观结构光谱性能

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航空发动机多源异构信息融合诊断新方法

振动．测试与诊断 2024年第1期44卷 186-192,206页

作者：张永强顾晓华杨杰中国航发商发制造测试中心上海201306 华南理工大学土木与交通学院广州510641

针对航空发动机实际工作中主要监测的气路、油路和机械振动3类参数,建立了全机故障方程,改进了现有技术仅考虑单类别发动机监测参数与故障模式的简单方法。在考虑同类别监测参数与故障模式的前提下,兼顾不同类别监测参数与不同类别故障... 详细信息

针对航空发动机实际工作中主要监测的气路、油路和机械振动3类参数,建立了全机故障方程,改进了现有技术仅考虑单类别发动机监测参数与故障模式的简单方法。在考虑同类别监测参数与故障模式的前提下,兼顾不同类别监测参数与不同类别故障模式之间的耦合关系,实现了多源异构监测数据的有效融合,解决了同型号多台发动机/单台发动机监测参数得到的同一故障模式的结果差异或矛盾的精化处理问题,给出了一种提高发动机故障诊断结果精度的新方法。

关键词：航空发动机多源异构信息数据融合故障诊断

隔震支座布置对地铁上盖多塔楼隔震结构的抗震性能影响分析

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结构工程师 2024年第2期40卷 91-100页

作者：张永强中铁第一勘察设计院集团有限公司西安710043

隔震支座的布置方式影响整隔震层的刚度,从而影响隔震效果。基于铅芯橡胶支座刚度占比和偏心率,确定了隔震支座的布置方式,研究了不同隔震支座布置方式对地铁上盖多塔楼隔震结构地震响应的影响。研究了隔震结构的减震系数、楼层加速度... 详细信息

隔震支座的布置方式影响整隔震层的刚度,从而影响隔震效果。基于铅芯橡胶支座刚度占比和偏心率,确定了隔震支座的布置方式,研究了不同隔震支座布置方式对地铁上盖多塔楼隔震结构地震响应的影响。研究了隔震结构的减震系数、楼层加速度、层间位移角、楼层位移和楼层剪力的变化规律。研究结果表明,铅芯橡胶支座刚度占比在一定范围内变化,对于隔震层及盖上结构,减震系数增大,楼层加速度、楼层位移、层间位移角和楼层剪力减小;对于盖下结构,减震系数和楼层剪力增大,楼层加速度和层间位移角减小,楼层位移几乎不变;偏心率在一定范围内变化,对于隔震层及盖上结构,减震系数和楼层加速度增大,楼层位移、层间位移角和楼层剪力减小;对于盖下结构,减震系数增大,层间位移角和楼层剪力减小;楼层加速度和楼层位移几乎没有变化。

关键词：地铁上盖开发多塔楼结构隔震结构铅芯橡胶支座刚度比偏心率

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基于物联网技术的智慧教室系统研究与设计

湖南邮电职业技术学院学报 2024年第2期23卷 15-19,38页

作者：张永强黎明职业大学福建泉州362000

物联网技术迅速发展,万物互联已成为不可逆转的趋势,教师如能充分利用这些技术的优势,将极大提升学校的信息化管理水平,改善学生的学习体验。针对传统多媒体教室的管理瓶颈,结合智慧教室的定义和系统功能需求,提出基于物联网技术的智慧... 详细信息

物联网技术迅速发展,万物互联已成为不可逆转的趋势,教师如能充分利用这些技术的优势,将极大提升学校的信息化管理水平,改善学生的学习体验。针对传统多媒体教室的管理瓶颈,结合智慧教室的定义和系统功能需求,提出基于物联网技术的智慧教室系统四层架构,智能设备的部署、数据传输、移动小程序等核心模块设计,以及门窗控制、照面控制、通风及温湿度控制、多媒体设备控制、消防系统控制等核心模块的系统实现,最后对系统使用维护给出了建议。

关键词：多媒体教室智慧教室物联网技术

井中永置式套管外三分量光纤MEMS地震检波器研究

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石油物探 2024年第1期63卷 149-160页

作者：梁兴李东明刘帅张永强中国石油天然气股份有限公司浙江油田分公司浙江杭州311100 中国船舶集团有限公司第七一五研究所浙江杭州310023

针对非常规油气井套管外永置式微振动监测,研制了一种基于光纤法布里帕罗(F-P)干涉原理和微机电(MEMS)技术的三分量光纤MEMS地震检波器,将微地震信号转化为F-P腔长的变化,通过超快光谱探测技术和动态白光干涉解调技术实现高速解调。设... 详细信息

针对非常规油气井套管外永置式微振动监测,研制了一种基于光纤法布里帕罗(F-P)干涉原理和微机电(MEMS)技术的三分量光纤MEMS地震检波器,将微地震信号转化为F-P腔长的变化,通过超快光谱探测技术和动态白光干涉解调技术实现高速解调。设计并理论仿真了μm/g量级的高灵敏度MEMS加速度芯片,突破大深度双面套刻工艺完成芯片样品制造。采用高集成度小型化结构设计、无胶封装工艺设计和陶瓷微加工工艺实现25 mm微型外径,满足套管外永置式安装要求,提高了高温检测精度。在实验室完成了检波器与标准电学加速度计的性能对比测试,结果表明:检波器可耐受175 MPa高压和180℃高温,灵敏度分别为1.2382,1.2590,1.0862μm/g,工作频带为0~350 Hz,量程为±5 g,线性度误差<0.01%,抗横向串扰能力<5%。研制的检波器耐高温高压、尺寸小巧、灵敏度高、线性度良好,在非常规油气井储层压裂改造和采油气生产过程中,永置式套管外的三分量光纤MEMS地震检波器可以发挥重要的监测作用。

关键词：光纤F-P传感永置式套管外三分量地震检波器 MEMS芯片耐高温高压

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