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先进射频封装技术发展面临的挑战

电子与封装 2016年第5期16卷 1-6页

作者：夏雨楠陈宇宁许丽清戴洲李华新程凯南京电子器件研究所南京210016

随着射频技术的广泛应用和发展,射频封装已经呈现出更高密度功能集成、更高功率、更高频率和更低成本的发展要求。在这些要求下,3D封装、大功率射频器件集成、多种信号混合集成、硅中道工艺顺应而出。相对于传统射频封装,基于硅中道工... 详细信息

随着射频技术的广泛应用和发展,射频封装已经呈现出更高密度功能集成、更高功率、更高频率和更低成本的发展要求。在这些要求下,3D封装、大功率射频器件集成、多种信号混合集成、硅中道工艺顺应而出。相对于传统射频封装,基于硅中道工艺的先进射频封装面临结构、热管理、信号完整性和工艺等多方面的挑战。

关键词：射频中介层 3D封装氮化镓

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杉木人工林更新木荷及荷杉混交林调查研究

南方林业科学 2017年第4期45卷 32-36页

作者：欧斌王建皓朱江华刘华新李畅欧述荣江西环境工程职业学院江西赣州341000 崇义林业股份有限公司江西崇义341500 赣州市森源科技种苗场江西安远342100

通过对杉木人工林采伐后更新造林不同类型林分的调查研究,对比分析其生长量及趋势变化,旨在探究不同清山处理方式下,南方地区杉木人工林更新模式。调查点设在赣州市崇义林业股份有限公司高坌林场,在炼山和不炼山(捡带)两种清山方式处理... 详细信息

通过对杉木人工林采伐后更新造林不同类型林分的调查研究,对比分析其生长量及趋势变化,旨在探究不同清山处理方式下,南方地区杉木人工林更新模式。调查点设在赣州市崇义林业股份有限公司高坌林场,在炼山和不炼山(捡带)两种清山方式处理下,分别设置类型Ⅰ杉木人工林更新杉木纯林(炼山)、类型Ⅱ杉木人工林更新杉木纯林(不炼山)、类型Ⅲ杉木人工林更新木荷纯林(炼山)、类型Ⅳ杉木人工林更新木荷纯林(不炼山)、类型Ⅴ杉木人工林更新荷杉混交林(炼山)5种更新造林模式。采用随机样圆地为标准地调查,对杉木人工林更新造林不同类型林分立木生长量、材积、直径生长规律进行调查。造林9~13 a林分,不炼山清山方式后更新造林各类型林分立木生长量均比炼山清山方式后更新造林林分立木生长量好;不同造林类型林分在树高、胸径、冠幅及材积生长量上都有一定差异;造林9 a的类型Ⅴ林分杉木树高生长量较造林11 a类型Ⅰ林分杉木树高生长量高出0.58 m;造林9 a的类型Ⅴ林分木荷的胸径和冠幅生长量要好于造林13 a类型Ⅲ林分木荷的胸径和冠幅生长量,分别高出0.40 cm、0.26 m;类型Ⅴ林分内,杉木材积为0.0546 m^3,木荷材积为0.0381 m^3;造林9 a的类型Ⅴ林分木荷材积生长量略高于造林13 a类型Ⅲ林分木荷材积生长量,但差异不显著。类型Ⅴ中,木荷直径年平均生长量呈递增趋势,前10 a内均比杉木直径生长好,第10年后,木荷直径年均生长放缓,木荷直径连年生长量在前7 a均呈现持续增长的趋势,显著区别于其他4个类型,在第7年时达到最大,为1.17 cm;杉木直径连年生长量从第9年开始持续增长,第11年左右达到最大值,为1.45 cm。杉木人工林采伐杉木后,不炼山(捡带)清山方式处理下造林林分生长显著好于炼山清山方式;类型Ⅴ杉木人工林更新荷杉混交林是较好的杉木人工林更新方式,木荷树种直径年均生长量有显著提高,直径连年生长量持续增长,2个树种间可形成较好的生长促进作用,可作为杉木人工林更新造林优选模式之一。

关键词：杉木人工林木荷人工林更新造林方式

Interface characterization of the discontinuously reinforced metal matrix composites based on wavelet analysis of acoustic emission behaviour

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Chinese Science Bulletin 1998年第9期43卷 791-792页

作者： Cui, Yan li, Xiaoli Peng, huaxin Yao, Zhongkai National Key Laboratory of Advanced Composites Beijing Institute of Aeronautical Materials Beijing China Harbin Institute of Technology Harbin China Beijing Science and Technology University Beijing China

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激光衍射法测定西格列他钠粒径分布

中国药物警戒 2024年第2期21卷 147-151页

作者：郭宁子刘丽岳瑞齐冯慧庆杨化新魏宁漪陈华中国食品药品检定研究院北京102629 国家药典委员会北京100061 马尔文帕纳科有限公司北京100040

目的建立西格列他钠的粒径分布测定方法,为药物粒径测定的方法开发和质量控制提供参考。方法采用MALVERN Mastersizer 3000激光衍射粒度仪和AEROS干法进样器建立西格列他钠的粒径分布方法。背景测量持续时间7 s;样品测量持续时间7 s;遮... 详细信息

目的建立西格列他钠的粒径分布测定方法,为药物粒径测定的方法开发和质量控制提供参考。方法采用MALVERN Mastersizer 3000激光衍射粒度仪和AEROS干法进样器建立西格列他钠的粒径分布方法。背景测量持续时间7 s;样品测量持续时间7 s;遮光度0.5%~5%;样品分散气压0.4 MPa;进样速度60%;文丘里管类型为高能文丘里管;料斗间隙2.5 mm。结果3批样品粒径分布特征值d(0.1)在1.02~1.17μm,d(0.5)在5.94~6.69μm,d(0.9)在20.70~22.40μm,平均标准偏差(RSD)均小于1%。结论建立了西格列他钠的粒度测定方法,可为其他易引湿药物的干法粒径测定方法开发提供参考。

关键词：激光衍射法西格列他钠粒径分布易引湿药物干法测定

Effect of Rejuvenators on Performance and Microstructure of Aged Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 341-345页

作者：况栋梁余剑英 CHEN huaxin FENG Zhengang li Rui YANG Hui Engineering Research Central of Pavement Materials Ministry of Education Chang'an University State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology School of Highway Chang'an University

A composite rejuvenator was used for the rejuvenation of aged asphalt in comparison with the common rejuvenator. The effects of the rejuvenators on the performance and microstructure of the aged asphalt were investigated by physical properties tests, dynamic shear rheometer and atomic force microscopy. The results indicate that the physical and rheological properties of the aged asphalt are restored more significantly by the composite rejuvenator than the common rejuvenator, which can be ascribed to the effective recovery of microstmcture of the aged asphalt. The composite rejuvenator has the potential to be used for the rejuvenation of severely aged asphalt since it can restore the colloidal structure of the aged asphalt effectively through composition regulation and chemical reactions between the composite rejuvenator and asphaltenes.

关键词： composite rejuvenator aged asphalt rejuvenation microstructure physical and rheological properties

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基准误差修正的弯管测量方法

汽车实用技术 2019年第13期45卷 94-96页

作者：张龙岗史鑫鹏贾婉侠左都宾李华新曹楠陕西重型汽车有限公司质量管理部陕西西安710200 陕西重型汽车有限公司汽车工程研究院陕西西安710200 陕西万方汽车零部件有限公司技术中心陕西西安710200

在空间弯管的测量中,为了减少坐标系的基准误差对测量结果的影响,首先对弯管的基准误差进行分类讨论,根据坐标系建立的步骤,针对不同的基准误差找出相应的修正方法,最后通过某排气管的实例测量来进行验证,证明了基准误差修正后的坐标系... 详细信息

在空间弯管的测量中,为了减少坐标系的基准误差对测量结果的影响,首先对弯管的基准误差进行分类讨论,根据坐标系建立的步骤,针对不同的基准误差找出相应的修正方法,最后通过某排气管的实例测量来进行验证,证明了基准误差修正后的坐标系可以提高测量结果的准确性。

关键词：基准误差弯管测量三坐标测量

Risk assessment and analysis of Traditional Chinese Medicine intervention in coronavirus disease

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Journal of Traditional Chinese Medicine 2022年第3期42卷 472-478页

作者： ZHAO Yufeng PANG huaxin LüLanting ZHOU Pei WANG Kaining CAI Shengxing ZHANG Huifeng li Kun Data Center of Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijing 100700China School of Computer and Information Technology Beijing Jiaotong UniversityBejing 100044China School of Public Administration and Policy Renmin University of ChinaBejing 100872China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100700China Vice President China Academy of Chinese Medical SciencesBeijing 100700China

OBJECTIVE:To explore the advantages of Traditional Chinese Medicine(TCM)in"prevention"and"control"of coronavirus disease 2019(COVID-19)***:In this paper,we wish to estimate the effect on the virus transmission of scenarios assuming TCM were used to build the first defense line at the very early stage of the spread in *** therefore first developed a classic susceptible infected removed(susceptible infected removed,SIR)transmission model based on the national data in China and then updated it to a TCM-SIR model to assess the potential impact of such assumptions,*** underlying risk of lives lost and social economy ***:(a)With the nationwide community lockdown,the risk value was from 90000 to 250000 without TCM intervention and the risk value was from 70000 to 220000 with TCM intervention;(b)Based the risk assessment method,we forecasted that the infections peak would be 58016 without TCM intervention,which happened on February ***,the infections peak would be 45713 with TCM intervention,which happened on 16 February ***:The adoption of nationwide community lockdown is conducive to timely control the epidemic and protect people’s lives and *** the same time,we can get lower infections if TCM intervention can be *** can also get the benefits from TCM prevention of COVID-19 pandemic by the basic number of infections.

关键词： COVID-19 medicine,Chinese traditional risk assessment public health

Simultaneous passivation of bulk and interface defects through synergistic effect of anion and cation toward efficient and stable planar perovskite solar cells

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Journal of Energy Chemistry 2021年第12期30卷 452-460,I0011页

作者： Cong Zhang huaxin Wang Haiyun li Qixin Zhuang Cheng Gong Xiaofei Hu Wensi Cai Shuangyi Zhao Jiangzhao Chen Zhigang Zang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Chongqing UniversityChongqing 400044.China

Bulk and interface carrier nonradiative recombination losses impede the further improvement of power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs).It is highly necessary to develop multifunctional strategy to minimize surface and interface nonradiative recombination ***,we report a bulk and interface defect passivation strategy via the synergistic effect of anions and cations,where multifunctional potassium sulphate(K_(2)SO_(4))is incorporated at SnO_(2)/perovskite *** find that K^(+)ions in K_(2)SO_(4)diffuse into perovskite layer and suppress the formation of bulk defects in perovskite films,and the SO_(4)^(2-)ions remain located at interface via the strong chemical interaction with SnO_(2)layer and perovskite layer,*** this synergistic modification strategy,effective defect passivation and improved energy band alignment are achieved *** beneficial effects are translated into an efficiency increase from 19.45%to 21.18%with a low voltage deficit of0.53 V mainly as a result of boosted open-circuit voltage(V_(oc))after K_(2)SO_(4)*** addition,the K_(2)SO_(4)modification contributes to ameliorated *** present work provides a route to minimize bulk and interface nonradiative recombination losses for the simultaneous realization of PCE and stability enhancement by rational anion and cation synergistic engineering.

关键词： Perovskite solar cells Interface engineering K_(2)SO_(4) Defect passivation Energy band alignment

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3D-ASL在急性缺血性脑卒中的研究进展

世界复合医学 2022年第1期8卷 195-198页

作者：李华鑫李瑞雄右江民族医学院研究生学院广西百色533000 附属梧州医院暨梧州市人民医院放射科广西梧州543000

三维动脉自旋标记(three-dimensional arterial spin labeling,3D-ASL)是近年来兴起的一项以自身动脉血中的水分子作为内源性示综剂,完全无创、可重复、安全的灌注技术,在关于急性缺血性脑卒中的诊断中起着重要作用。该文就3D-ASL脑灌... 详细信息

三维动脉自旋标记(three-dimensional arterial spin labeling,3D-ASL)是近年来兴起的一项以自身动脉血中的水分子作为内源性示综剂,完全无创、可重复、安全的灌注技术,在关于急性缺血性脑卒中的诊断中起着重要作用。该文就3D-ASL脑灌注技术进行介绍,并对其在急性缺血性脑卒中关于侧支循环、缺血半暗带、动脉闭塞、出血转化的临床应用展开综述,并分析其现存的局限性及展望,以期3D-ASL灌注更好地应用于临床与科研。

关键词：三维动脉自旋标记急性缺血性脑卒侧支循环缺血半暗带出血转化

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