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Fluorene pendant-functionalization of poly(N-vinylcarbazole)as deep-blue fluorescent and host materials for polymer light-emitting diodes

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中国化学快报:英文版 2023年第8期34卷 484-489页

作者： Ning Sun Qin Zou Wenyu Chen Yingying Zheng Kai Sun Chunbin li Yamin Han Lubing Bai Chuanxin Wei jinyi lin Chengrong Yin Jianguo Wang Wei Huang Key Laboratory of Flexible Electronics(KLOFE)and Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing 211816China College of Chemistry and Chemical Engineering Inner Mongolia Key Laboratory of Fine Organic SynthesisInner Mongolia UniversityHohhot 010021China Centre for Molecular Systems and Organic Devices(CMSOD) Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China Shaanxi Institute of Flexible Electronics(SIFE) Northwestern Polytechnical University(NPU)Xi’an 710072China

π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance and stability of deep-blue polymer light-emitting diodes(PLEDs).Herein,considerate of“defect”carbazole(Cz)electromers in poly(N-vinylcarbazole)(PVK),a series of fluorene units are introduced into pendant segments(PVCz-DMeF,PVCz-FMeNPh and PVCz-DFMeNPh)to suppress the strongπ-electron coupling of pendant Cz units and enhance radiative transition toward fabricating sable PLEDs.Compared to PVCz-FMeNPh and PVCz-DFMeNPh,PVCz-DMeF spin-coated films show a relatively efficient deep-blue emission,completely similar to its single pendant chromophore,confirmed an extremely weak charge-transfer and electron coupling between adjacent pendant segments.Therefore,PLEDs based on PVCz-DMeF present stable and deep-blue emission with a high color purity(0.17,0.08),associated with extremely weak defect emission at 600∼700nm(induced by carbazole electromers).Finally,PLEDs based on PVCz-DMeF/F8BT blended films(1:1)also present the high maximum luminance(Lmax)of 6261 cd/m2 and current efficiency(CE_(max))of 2.03 cd/A,confirmed slightly trapped sites formation.Therefore,precisely control the arrangement and packing model of pendant units inπ-stacked polymer is an essential prerequisite for building efficient and stable emitter for optoelectronic devices.

关键词： Poly(N-vinylcarbazole) Fluorene Deep-blue emission Energy transfer Polymer light-emitting diodes

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车载全景图技术在“数字寿光”建设中的应用

北京测绘 2024年第5期38卷 692-697页

作者：全金谊崔超王辉孟祥明高明超李铭张帅帅济南市勘察测绘研究院山东济南250000 寿光市地理信息中心山东寿光262700 寿光市自然资源和规划局山东寿光262700

车载全景图技术是一种对街道场景进行深度复刻的新型城市街景地图制作方式,也是推进“数字中国”建设的前沿技术之一。本文结合智慧城市建设服务和互联网地图升级需求,探讨了由三维激光扫描设备、全景相机、卫星定位模块、惯性导航装置... 详细信息

车载全景图技术是一种对街道场景进行深度复刻的新型城市街景地图制作方式,也是推进“数字中国”建设的前沿技术之一。本文结合智慧城市建设服务和互联网地图升级需求,探讨了由三维激光扫描设备、全景相机、卫星定位模块、惯性导航装置以及车轮编码器等组成的HiScan-R轻量化车载全景技术解决方案在新型城市街景地图中的应用。在寿光市“数字赋能”建设的推动下,采用车载全景图制作技术,针对其市区街道进行实践,对车载全景移动三维测量数据采集、视频流街景轨迹融合的全过程进行了研究,并对街景地图及其兴趣点功能进行展示,为城市经济、环境及交通等的综合管理提供了重要的参考价值。

关键词：车载全景移动三维测量系统街景地图兴趣点全景技术 “数字寿光”

Ganglioside GD3 synthase(GD3S),a novel cancer drug target

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Acta Pharmaceutica Sinica B 2018年第5期8卷 713-720页

作者： jinyi liu Xiangjin Zheng Xiaocong Pang li li Jinhua Wang Cui Yang Guanhua Du Ethnic Drug Screening & Pharmacology Center Key Laboratory of Chemistry in Ethnic Medicinal Resources State Ethnic Affairs Commission & Ministry of Education Yunnan Minzu University Key Laboratory of Drug Target Research and Drug Screen Institute of Materia Medica Chinese Academy of Medical Science and Peking Union Medical College The State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Science and Peking Union Medical College

Gangliosides are a class of important glycosphingolipids containing sialic acid that are widely distributed on the outer surface of cells and are abundantly distributed in brain tissue. Disialoganglioside with three glycosyl groups(GD3) and disialoganglioside with two glycosyl groups(GD2) are markedly increased in pathological conditions such as cancers and neurodegenerative diseases. GD3 and GD2 were found to play important roles in cancers by mediating cell proliferation, migration, invasion, adhesion,angiogenesis and in preventing immunosuppression of tumors. GD3 synthase(GD3S) is the regulatory enzyme of GD3 and GD2 synthesis, and is important in tumorigenesis and the development of cancers.The study of GD3S as a drug target may be of great significance for the discovery of new drugs for cancer treatment. This review will describe the gangliosides and their roles in physiological and pathological conditions; the roles of GD3 and GD2 in cancers; the expression, functions and mechanisms of GD3S,and its potential as a drug target in cancers.

关键词： Ganglioside GD3 GD2 GD3S Drug target Cancer treatment

Early Carboniferous High Ba-Sr Granitoid in Southern Langshan of Northeastern Alxa: Implications for Accretionary Tectonics along the Southern Central Asian Orogenic Belt

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 820-844页

作者： ZHENG Rongguo li jinyi ZHANG Jin XIAO Wenjiao li Yi Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChineseAcademy of SciencesUrumqi 830011China State Key Laboratory of lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Tibetan Plateau Earth Science Chinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing 100049China China Minmetals Corporation Beijing 100010China

Voluminous granitoids are widely distributed in the Langshan region,northeast of the Alxa block,and record the evolutionary processes of the southern Central Asian Orogenic Belt.The Dabashan pluton was emplaced into the Paleoproterozoic Diebusige complex.Early Carboniferous zircon LA-ICP MS U-Pb ages were from 327 Ma to 346 Ma.The Dabashan pluton can be classified as monzogranite and syenogranite,and exhibits high K2 O contents and K2 O/Na2 O ratios,which reveal a high-K calc-alkaline nature.The samples display strongly fractionated REE patterns,and are enriched in large ion lithophile elements(liLE)relative to high field strength elements(HFSE).The Dabashan plutons display unusually high Ba(823–2817 ppm)and Sr(166–520 ppm)contents and K/Rb ratios(315–627),but low Rb/Ba ratios(0.02–0.14),and exhibit fertile zircon Hf isotopic compositions[εHf(t)=-14 to-20],which are comparable to those of typical high Ba–Sr granitoids.Based on the geochemical compositions of the samples,we suggest that subducted sediments and ancient crustal materials both played important roles in their generation.Basaltic melts were derived from partial melting of subcontinental lithophile mantle metasomatized by subducted sediment-related melts with residual garnet in the source,which caused partial melting of ancient lower crust.Magmas derived from underplating ascended and emplaced in the middle–upper crust at different depths.The resultant magmas experienced some degree of fractional crystallization during their ascent.Given these geochemical characteristics,together with regional tectonic,magmatic,and structure analysis data,an active continental margin environment is proposed for the generation of these rocks.

关键词： LA–ICP MS U–Pb Zircon Hf isotope high Ba–Sr granites CAOB Alxa

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细间距QFN器件焊接工艺设计

电子工艺技术 2024年第2期45卷 37-40页

作者：李亚飞张钧翀黄莹董姝唐盘良陈彦光马晋毅中国电子科集团公司第二十六研究所重庆400060

QFN器件体积小、质量轻、电性能及散热性能好,广泛应用于高可靠电路中。由于底部散热焊盘面积较大,极易产生焊接空洞问题。特殊的封装制程使得QFN焊端侧面裸铜,暴露空气氧化后难以爬锡。针对上述问题,从PCB焊盘设计、焊膏印刷及回流焊... 详细信息

QFN器件体积小、质量轻、电性能及散热性能好,广泛应用于高可靠电路中。由于底部散热焊盘面积较大,极易产生焊接空洞问题。特殊的封装制程使得QFN焊端侧面裸铜,暴露空气氧化后难以爬锡。针对上述问题,从PCB焊盘设计、焊膏印刷及回流焊接等方面展开试验,对比QFN器件侧面焊盘爬锡、底部焊盘空洞率等情况,优化了QFN器件组装效果,提高了QFN器件的应用可靠性。

关键词： QFN器件焊盘设计焊膏印刷回流焊

Mesozoic-Cenozoic Multi-Stage Intraplate Deformation Events in the Langshan Region and their Tectonic Implications

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 78-102页

作者： ZHANG Jin li jinyi li Yanfeng QI Wenhua ZHANG Yiping Institute of Geology Chinese Academy of Geological Sciences National Earthquake Response Support Service Institute of Geology Chinese Earthquake Administration

In the Langshan region, northwestern China, marked multi-stage intraplate deformation events have occurred since the Mesozoic, including（1） northeast-striking ductile left-lateral strike slip during the Middle-Late Triassic, which is closely related to the collision between the North China and the Yangtze plates;（2） top-to-the-southeast thrust with northwest-southeast trending maximum compression during the Late Jurassic;（3） nearly eastward detachment during the Early Cretaceous;（4） top-to-the-northwest thrust with northwest-southeast trending maximum compression during the Late Cretaceous and Early Cenozoic;（5） northeast-striking brittle left-lateral strike slip with nearly north-south trending maximum compression; and（6） northwest-southeast extension during the Middle-Late Cenozoic. All these deformation events belong to the intraplate deformation across the entire Central Asian region and respond to the tectonic events along the plate boundaries or deep tectonics. The structures developed in early events in the crust were the most important factors controlling the later deformation styles, and few new structures have later developed. Based on previous research and our results, the paleostress inversion in the Langshan region shows that the Mesozoic intraplate deformations in the study region mainly resulted from the tectonic events from the Paleo-Pacific region and have no or a weak relation to the Tethys region. During the Late Jurassic, the maximum compression from the Mongolia-Okhotsk region cannot be excluded. The Langshan region is the bridge between southern Mongolia and the western Ordos tectonic belt and is thus important to understand the nature and relationship between both regions.

关键词： Langshan,intraplate deformation,Mesozoic,Cenozoic,North China Craton,Alxa block

MELK is an oncogenic kinase essential for metastasis,mitotic progression,and programmed death in lung carcinoma

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Signal Transduction and Targeted Therapy 2021年第1期6卷 83-94页

作者： Qin Tang Wan li Xiangjin Zheng liwen Ren jinyi liu Sha li Jinhua Wang Guanhua Du The State Key Laboratory of Bioactive Substance and Function of Natural Medicines BeijingChina Key Laboratory of Drug Target Research and Drug Screen Institute of Materia MedicaChinese Academy of Medical Science and Peking Union Medical College100050 BeijingChina

Lung cancer is the fastest growth rate of morbidity and mortality in nearly a decade,and remains difficult to treat.Furthermore,the molecular mechanisms underlying its development are still unclear.In this study,bioinformatics analysis showed that MELK was highly expressed in lung cancer and negatively correlated to the survival of lung adenocarcinoma(LUAD).Immunohistochemistry analysis of LUAD patient tissues revealed there were a high level of MELK expression in LUAD.Knockdown of MELK expression inhibits the migration and invasion of LUAD cells,which may be mediated by Twist1,Slug,MMP7,and N-catenin.Overexpression of MELK promoted the growth of LUAD cells in medium,3D Matrigel,and nude mice.Inhibition of MELK by OTSSP167 arrested cycle of LUAD cells at G2/M phase via PLK1-CDC25C-CDK1 pathway,and triggered apoptosis-mediated pyroptosis.Together,these data indicate that MELK is critical for metastasis,mitotic progression,and programmed death of LUAD and may be a promising therapeutic target for LUAD.

关键词： metastasis PLK1 lung

基于知识点模块整合的情景案例教学法在急诊与灾难医学教学中的应用研究

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广西中医药大学学报 2024年第1期27卷 76-78页

作者：唐晓何锦轶伍民生陈盛奎康雪莹胡炳全李宏一梁皓广西中医药大学附属瑞康医院广西南宁530011

[目的]探讨基于知识点模块整合的情景案例教学法在急诊与灾难医学教学中的应用效果。[方法]将60名实习生按随机数字表法分为对照组和试验组各30名,对照组接受传统教学法,试验组接受基于知识点模块整合的情景案例教学法。对比两组的整体... 详细信息

[目的]探讨基于知识点模块整合的情景案例教学法在急诊与灾难医学教学中的应用效果。[方法]将60名实习生按随机数字表法分为对照组和试验组各30名,对照组接受传统教学法,试验组接受基于知识点模块整合的情景案例教学法。对比两组的整体临床实践能力评分、理论考核成绩和操作考核成绩。[结果]试验组的整体实践能力评分高于对照组(P<0.05或P<0.01),基础理论、基本知识等理论成绩均高于对照组(P<0.01),现场急救、创伤急救、疾病救治、心肺复苏、急性中毒处理、理化环境损伤处理等操作成绩均高于对照组(P<0.01)。[结论]基于知识点模块整合的情景案例教学法,可提高急诊与灾难医学的临床带教效果,有助于实习生掌握理论知识与操作技能,促进整体实践能力的提高。

关键词：急诊与灾难医学教学情景案例教学法知识点模块

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钛合金零件去应力退火热处理变形研究

热加工工艺 2024年第4期53卷 151-154页

作者：易吉豪蔡明勇李栎森唐维之叶翔宇华程康进武刘瑾怡帅仕祥刘洪廖文龙成都飞机工业(集团)有限责任公司四川成都610092 清华大学材料学院先进成形制造教育部重点实验室北京100084

利用ABAQUS软件对某钛合金框零件在去应力退火热处理过程中的变形问题进行数值模拟研究。考虑了锻造、机加等前端工序带来的残余应力对后续零件热处理变形的影响,实现了基于实际制造的连续多过程、多物理场耦合的仿真分析。同时充分考... 详细信息

利用ABAQUS软件对某钛合金框零件在去应力退火热处理过程中的变形问题进行数值模拟研究。考虑了锻造、机加等前端工序带来的残余应力对后续零件热处理变形的影响,实现了基于实际制造的连续多过程、多物理场耦合的仿真分析。同时充分考虑零件实际热处理过程中同工装的装配和接触关系,研究了工装对零件热处理变形的影响。结果表明,在考虑初始残余应力的情况下,自由放置的零件在热处理过程中伴随着内应力的释放和重新分布发生了蠕变,变形趋势同实际测量结果一致,且变形大小在同一数量级。此外,采用同材质的钛合金工装配合随形块的装夹方式能够减小热处理过程中工装对零件的影响,有效保证零件外形,从而达到控制零件热处理变形的目的。

关键词：钛合金热处理变形数值模拟