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Coaxial boron nitride nanotubes as interfacial dielectric layers to lower interface trap density in carbon nanotube transistors

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Nano Research 2023年第11期16卷 12840-12848页

作者： Keigo otsuka Taiki Sugihara Taiki Inoue Weijie Jia Satoru Matsushita Takanobu Saito Minhyeok Lee Takashi Taniguchi Kenji Watanabe Gregory Pitner Ming-Yang Li tzu-ang Ch.o Rong Xiang Shohei Chiashi Shigeo Maruyama Department of Mechanical Engineering The University of TokyoTokyo 113-8656Japan Department of Applied Physics Osaka UniversityOsaka 565-0871Japan Research Center for Materials Nanoarchitectonics National Institute for Materials ScienceTsukuba 305-0044Japan Research Center for Electronic and optical Materials National Institute for Materials ScienceTsukuba 305-0044Japan Corporate Research Taiwan Semiconductor Manufacturing CompanySan JoseCA 95134USA Corporate Research Taiwan Semiconductor Manufacturing CompanyHsinchu 30078

A semiconductor/dielectric interface is one of the dominant factors in device characteristics,and a variety of oxides with high dielectric constants and low interface trap densities have been used in carbon nanotube *** the crystal structure of nanotubes with no dangling bonds,there remains room to investigate unconventional dielectric ***,we fabricate carbon nanotube transistors with boron nitride nanotubes as interfacial layers between channels and gate dielectrics,where a single semiconducting nanotube is used to focus on switching behaviors at the subthreshold *** subthreshold swing of 68 mV·dec^(−1)is obtained despite a 100-nm-thick Sio_(2)dielectric,corresponding to the effective interface trap density of 5.2×10^(11)cm^(−2)·eV^(−1),one order of magnitude lower than those of carbon nanotube devices without boron nitride *** interfacial layers also result in the mild suppression of threshold voltage variation and *** achieve ohmic contacts th.ough the selective etching of boron nitride nanotubes with XeF2 gas,overcoming the trade-off imposed by wrapping the inner *** impacts of fluorinating carbon nanotubes on device performances are also confirmed as long as the etching is applied exclusively at source/drain *** results represent an important step toward nanoelectronics that exploit the advantage of one-dimensional van der Waals heterostructures.

关键词： carbon nanotubes hexagonal boron nitride van der Waals interfaces field-effect transistors subthreshold swing selective etching

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三种马鲛鱼快速检测方法的建立及应用

食品安全导刊 2024年第7期 67-72页

作者：杨健琪李昂柳淑芳大连海洋大学水产与生命学院辽宁大连116023 中国水产科学研究院黄海水产研究所农业农村部海洋渔业可持续发展重点实验室山东青岛266071

为了准确快速鉴定马鲛鱼样品,本研究分别以线粒体Cytb和D-loop为靶基因,筛选出康氏马鲛、蓝点马鲛与斑点马鲛的特异性PCR扩增引物,建立了3种马鲛鱼的快速检测方法,并对检测方法的特异性、重复性和灵敏性进行了验证,随后运用该方法对市... 详细信息

为了准确快速鉴定马鲛鱼样品,本研究分别以线粒体Cytb和D-loop为靶基因,筛选出康氏马鲛、蓝点马鲛与斑点马鲛的特异性PCR扩增引物,建立了3种马鲛鱼的快速检测方法,并对检测方法的特异性、重复性和灵敏性进行了验证,随后运用该方法对市售马鲛鱼及其加工制品进行检测。结果表明,马鲛鱼的快速检测方法具有良好的特异性和重复性,灵敏性检测限低于2.000 ng·μL^(-1) DNA,运用该方法能快速检测出原料及加工产品中的马鲛鱼成分,整个过程最短用时2 h。本研究建立的3种马鲛鱼PCR快速检测方法,可实现马鲛鱼物种鉴定,满足日常检测需求,对防止水产品掺假、维护消费者权益、规范市场秩序具有重要意义。

关键词：聚合酶链式反应(PCR) 马鲛鱼快速检测物种鉴定

星际分子1-氰基-1,3-丁二烯的气相合成机制研究

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华东师范大学学报（自然科学版） 2024年第4期 57-64页

作者：郑慧敏白西林龚起昂杨涛华东师范大学精密光谱科学与技术国家重点实验室上海200241

为深入了解星际有机腈分子的动力学生成机制,结合同步辐射真空紫外光电离实验和量子化学计算,研究了高温星际环境中氰甲基自由基(·Ch_(2)CN)与丙炔(C_(3)h_(4))的反应机制.通过分析光电离质谱与光电离效率图,发现反应可能主要产生1-氰... 详细信息

为深入了解星际有机腈分子的动力学生成机制,结合同步辐射真空紫外光电离实验和量子化学计算,研究了高温星际环境中氰甲基自由基(·Ch_(2)CN)与丙炔(C_(3)h_(4))的反应机制.通过分析光电离质谱与光电离效率图,发现反应可能主要产生1-氰基-1,3-丁二烯开链异构体.继而,在B3LYP/cc-pVTZ水平上计算了反应势能面,发现氰甲基自由基可无势垒地加成到丙炔上,主要产生gauche-E-1-氰基-1,3-丁二烯和E-1-氰基-1,3-丁二烯这两种产物,而热力学上更稳定的产物吡啶的生成概率较小.

关键词：反应动力学 1-氰基-1,3-丁二烯星际分子

基于CoRS网数据的河南“7·20”特大暴雨期间大气水汽分布特征分析

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华北水利水电大学学报（自然科学版） 2024年第1期45卷 21-30页

作者：李慧张亚豪朱丹彤高旭昂华北水利水电大学河南郑州450046

河南“7·20”特大暴雨导致了严重的城市内涝和多起地质灾害。大气水汽是发生极端降雨的主要驱动力之一,分析“7·20”特大暴雨期间大气水汽的时空变化,有助于提高对降雨-水汽区域性作用机制的认识。利用河南CoRS网中8个GNSS测站的观测... 详细信息

河南“7·20”特大暴雨导致了严重的城市内涝和多起地质灾害。大气水汽是发生极端降雨的主要驱动力之一,分析“7·20”特大暴雨期间大气水汽的时空变化,有助于提高对降雨-水汽区域性作用机制的认识。利用河南CoRS网中8个GNSS测站的观测数据,反演了暴雨前后(7月17—24日)时间分辨率为5 min的PWV数据,在此基础上与基于ERA-5再分析数据通过积分求得的PWV值进行了对比,并结合实际降雨量分析了暴雨期间水汽的时空分布特征。结果表明:GNSS-PWV的偏差和均方根误差分别为0.4、2.3 mm;暴雨前3 d内PWV值呈现快速上升趋势,并在暴雨前3 h达到最大值,在7月22日后逐渐减少到正常范围;GNSS-PWV的变化趋势与实际降雨过程基本符合。研究结果可为基于GNSS观测数据的实时全天候气象预警工作提供一定的理论基础。

关键词： GNSS 大气水汽再分析数据 “7·20”特大暴雨

Precise Rates in the Law of the Logarithm for the Moment Convergence in hilbert Spaces

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Acta Mathematica Sinica,English Series 2009年第2期25卷 191-208页

作者： Ke ang FU Li Xin Zhang Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China Sch.ol of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310035 P. R. China

Let （X, Xn; n ≥1） be a sequence of i.i.d, random variables taking values in a real separable hilbert space （h, ｜｜·｜｜） with covariance operator ∑. Set Sn = X1 ＋ X2 ＋ ... ＋ Xn, n≥ 1. We prove that, for b 〉 -1, lim ε→0 ε^2（b＋1） ∞ ∑n=1 （logn）^b/n^3/2 E{｜｜Sn｜｜-σε√nlogn}=σ^-2（b＋1）/（2b＋3）（b＋1） B｜｜Y｜^2b＋3holds if EX=0,and E｜｜X｜｜^2（log｜｜x｜｜）^3bv（b＋4）〈∞ where Y is a Gaussian random variable taking value in a real separable hilbert space with mean zero and covariance operator ∑, and σ^2 denotes the largest eigenvalue of ∑.

关键词： the law of the logarithm moment convergence tail probability strong approximation

Development of a Compact Photoacoustic Tomography Imaging System with Dual Single-Element Transducers for Image Enhancement

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Current Medical Science 2021年第6期41卷 1151-1157页

作者： Yong-jian Zh.o Xiao-long ZhU Pei-yu LUo ang LI Wei XIAo Xiao XIAo Li LIU Max Q.-h.MENG Department of Electronic and Electrical Engineering the Southern University of Science and TechnologyShenzhen 518055China Department of Electronic Engineering The Chinese University of Hong KongHong Kong 999077China Shenzhen Research Institute of The Chinese University of hong Kong in Shenzhen Shenzhen 518172China

objective:This paper proposes a new photoacoustic computed tomography(PACT)imaging system employing dual ultrasonic transducers with different *** imaging complex biological tissues,photoacoustic(PA)signals with multiple frequencies are produced simultaneously;however,due to the limited bandwidth.of a single-frequency transducer,the received PA signals with specific frequencies may be missing,leading to a low imaging ***:In contrast to our previous work,the proposed system has a compact volume as well as specific selection of the detection center frequency of the transducer,which can provide a comprehensive range for the detection of PA *** this study,a series of numerical simulation and phantom experiments were performed to validate the efficacy of the developed PACT ***:The images generated by our system combined the advantages of both high resolution and ideal brightness/***:The interchangeability of transducers with different frequencies provides potential for clinical deployment under the circumstance where a single frequency transducer cannot perform well.

关键词： photoacoustic tomography dual transducers image enhancement signal responding range

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赤子爱胜蚓油脂的提取及脂肪酸组成分析

中国油脂 2024年第7期49卷 118-123,152页

作者：王珂欣贾京华刘薇刘蓬宇张博毅高昂天津中医药大学公共卫生与健康科学学院天津300000 天津民生生物工程股份有限公司天津300000

为促进蚯蚓蛋白粉加工副产物的开发与利用,以赤子爱胜蚓渣料为原料,采用超声辅助水酶法结合酸水解法提取蚯蚓油,研究酶种类、酶解时间和加酶量对蚯蚓油得率的影响,通过正交实验确定最佳酶解条件。同时,对提取的蚯蚓油理化指标及脂肪酸... 详细信息

为促进蚯蚓蛋白粉加工副产物的开发与利用,以赤子爱胜蚓渣料为原料,采用超声辅助水酶法结合酸水解法提取蚯蚓油,研究酶种类、酶解时间和加酶量对蚯蚓油得率的影响,通过正交实验确定最佳酶解条件。同时,对提取的蚯蚓油理化指标及脂肪酸组成进行分析。结果表明:超声辅助水酶法结合酸水解法提取蚯蚓油的最佳酶解条件为使用胃蛋白酶(适宜温度50℃、ph 2.0)、酶解时间2.0 h、加酶量4%,在此条件下蚯蚓油得率为11.45%;蚯蚓原油为浅棕色,稍有浑浊,稍有蚯蚓特有的土腥味,略带有油脂酸败味;蚯蚓油由24种脂肪酸构成,其中饱和脂肪酸含量较高,占总脂肪酸的82.381%,主要为硬脂酸、月桂酸,单不饱和脂肪酸占总脂肪酸的8.565%,主要为油酸、棕榈油酸,多不饱和脂肪酸占总脂肪酸的8.995%,主要为亚油酸,另外蚯蚓油奇数碳脂肪酸含量为13.867%。综上,超声辅助水酶法结合酸水解法对于提取蚯蚓渣料中的油脂有一定效果,具备实际应用的潜力,且得到的蚯蚓油含有丰富的奇数碳脂肪酸,营养价值较高。

关键词：蚯蚓油水酶法提取工艺脂肪酸组成

大型基础设施系统设计中的风险及概率(英文)

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重庆交通大学学报（自然科学版） 2011年第A2期30卷 1084-1089,1232页

作者： A.h-S.ang 加利福尼亚大学埃文校区美国加利福尼亚

在大型基础设施系统中,不可避免地会出现重大的不确定性,因而,无法确保已建系统的安全性和可靠性。有功能失效甚至破坏的可能,同时也有相应的规避风险的措施。从实用角度出发,不确定性可以分为两大类:数据型(又称偶然型)不确定性和知识... 详细信息

在大型基础设施系统中,不可避免地会出现重大的不确定性,因而,无法确保已建系统的安全性和可靠性。有功能失效甚至破坏的可能,同时也有相应的规避风险的措施。从实用角度出发,不确定性可以分为两大类:数据型(又称偶然型)不确定性和知识型(又称认知型)不确定性。前者可以通过对数据的观察来评估,而后者则需要主观判断。系统地分析了这两类不确定性,得到有关风险预测的信息,为大型基础设施设计提供基于安全(即规避风险)的建议;对在地震荷载下大型基础设施进行了安全设计;以韩国某斜拉桥为例,对其进行了数值化评估及最低生命周期成本设计。

关键词：风险概率不确定性安全性可靠性基础设施桥梁设计

Modeling and flapping vibration suppression of a novel tailless flapping wing micro air vehicle

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Chinese Journal of Aeronautics 2022年第3期35卷 309-328页

作者： Siqi Wang Bifeng SoNG ang ChEN Qiang FU Jin CUI Sch.ol of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Sch.ol of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

This paper establishes and analyzes a high-fidelity nonlinear time-periodic dynamic model and the corresponding state observer for flapping vibration suppression of a novel tailless Flapping Wing Micro Air Vehicle(FWMAV),named ***,a complete modeling of NPU-Tinybird is determined,including the aerodynamic model based on the quasi-steady method,the kinematic and dynamic model about the mechanism of flapping and attitude control,combined with the single rigid body dynamic *** on this,a linearized longitudinal pitch dynamic cycle-averaged model is obtained and analyzed th.ough the methods of neural network fitting and system identification,preparing for the design of flapping vibration suppression *** vibration is an inherent property of the tailless FWMAV,which arises from the influence of time-periodic aerodynamic forces and *** can be captured by attitude and position sensors on the plane,which impairs the flight performance and efficiency of flight controller and *** deal with this problem,a novel state observer for flapping vibration suppression is designed.A robust optimal controller based on the linear quadratic th.ory is also designed to stabilize the closed-loop *** results are given to verify the performance of the observer,including the closed loop responses combined with robust optimal controller,the comparison of different parameters of observer and the comparison with several classic methods,such as Kalman filter,h-infinity filter and low-pass filter,which prove that the novel observer owns a fairly good suppression effect on flapping vibration and benefits for the improvement of flight performance and control efficiency.

关键词： Flapping vibration Flapping wing Linear quadratic th.ory Robust control State observer