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Method of evaluating interface traps in Al2O3/AlgaN/gaN high electron mobility transistors

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Chinese Physics B 2019年第6期28卷 378-383页

作者： si-Qin-gao-wa Bao Xiao-Hua Ma Wei-Wei Chen Ling Yang Bin Hou Qing Zhu Jie-Jie Zhu Yue Hao School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710071China Key Laboratory of Wide Band-gap Semiconductor Materials and Devices School of MicroelectronicsXidian UniversityXi’an 710071China School of Science Inner Mongolia University of TechnologyHohhot 010051China 4China Academy of Space Technology(Xi’an)Xi’an 710071China

In this paper, the interface states of the AlgaN/gaN metal–insulator–semiconductor(MIS) high electron mobility transistors(HEMTs) with an Al2 O3 gate dielectric are systematically evaluated. By frequency-dependent capacitance and conductance measurements, trap density and time constant at Al2 O3/AlgaN and AlgaN/gaN interface are *** experimental results reveal that the density of trap states and the activation energy at the Al2 O3/AlgaN interface are much higher than at the AlgaN/gaN interface. The photo-assisted capacitance-voltage measurements are performed to characterize the deep-level traps located near mid-gap at the Al2 O3/AlgaN interface, which indicates that a density of deep-level traps is lower than the density of the shallow-level states.

关键词： AlgaN/gaN HEMTs interface traps frequency-dependent C–V measurements photo-assisted C–V measurements

先天性心脏病儿童156例营养不良发生现状及影响因素分析

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安徽医药 2025年第1期29卷 83-86页

作者：肖瑾朱琳陈思陕西省森林工业职工医院儿童保健科陕西西安710300

目的探讨先天性心脏病儿童营养不良发生现状及影响因素。方法选取陕西省森林工业职工医院2019年6月至2022年7月收治的156例先天性心脏病病人,采用Z评分法评估病人的营养状况。根据病人营养状况将其分为营养不良组和正常组,比较两组病人... 详细信息

目的探讨先天性心脏病儿童营养不良发生现状及影响因素。方法选取陕西省森林工业职工医院2019年6月至2022年7月收治的156例先天性心脏病病人,采用Z评分法评估病人的营养状况。根据病人营养状况将其分为营养不良组和正常组,比较两组病人一般资料,采用多因素回归分析先天性心脏病病人营养不良的影响因素。结果156例先天性心脏病病人中营养不良发生率为58.97%,其中急性营养不良发生率为26.92%,慢性营养不良发生率为32.05%;营养不良组病情复杂占比(57.61%比34.37%)、家庭经济收入低占比(45.65%比21.88%)、母亲对疾病感知度不准确占比(57.61%比35.94%)、低出生体质量儿占比(38.04%比23.44%)、心脏增大占比(21.74%比9.37%)、治疗前有症状占比(73.91%比34.38%)、确诊时间≥1年占比(68.48%比29.69%)、住院次数>4次占比(33.70%比12.50%)、感染占比(70.65%比29.69%)及来自农村占比(63.04%比40.62%)均高于营养正常组(均Pgistic回归分析发现,病情复杂程度、家庭经济收入、出生体质量、确诊时间、住院次数及感染均是先天性心脏病病人发生营养不良的独立危险因素(P<0.05)。结论病情复杂程度、出生体质量、住院次数以及家庭来源均是先天性心脏病病人营养不良的独立危险因素。

关键词：先天性心脏病儿童营养不良营养状况影响因素

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Theoretical study on the mechanism of sulfur migration to gas in the pyrolysis of benzothiophene

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Frontiers of Chemical Science and Engineering 2023年第3期17卷 334-346页

作者： Ji Liu Shuang-Wei Yang Wei Zhao Yu-Long Wu Bin Hu si-Han Hu Shan-Wei Ma Qiang Lu National Engineering Research Center of New Energy Power generation North China Electric Power UniversityBeijing 102206China Suzhou Institute of North China Electric Power University Suzhou 215000China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China School of Chemistry and Chemical Engineering Xinjiang UniversityUrumqi City 830046China

The release and control of sulfur species in the pyrolysis of fossil fuels and solid wastes have attracted attention ***,thiophene derivatives are important intermediates for the sulfur gas release from organic sulfur,but the underlying migration mechanisms remain ***,the mechanism of sulfur migration during the release of sulfur-containing radicals in benzothiophene pyrolysis was explored through quantum chemistry *** C_(1)-to-C_(2)H-transfer has the lowest energy barrier of 269.9 kJ·mol-1 and the highest rate constant at low temperatures,while the elevated temperature is beneficial for C−S bond homolysis.2-Ethynylbenzenethiol is the key intermediate for the formation of S and SH radicals with the overall energy barriers of 408.0 and 498.7 kJ·mol-1 in favorable *** generation of CS radicals is relatively difficult because of the high energy barrier(551.8 kJ·mol-1).However,it can be significantly promoted by high temperatures,where the rate constant exceeds that for S radical generation above 930°***,the strong competitiveness of S and SH radicals results in abundant H2 S during benzothiophene pyrolysis,and the high temperature is more beneficial for CS2 generation from CS *** study lays a foundation for elucidating sulfur migration mechanisms and furthering the development of pyrolysis techniques.

关键词： benzothiophene sulfur migration pyrolysis density functional theory

Ion specificity in NaCl solution confined in silicon nanochannels

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Science China(Technological Sciences) 2014年第1期57卷 230-238页

作者： QIU YingHua TAN QiYan si Wei CHEN YunFei School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments Southeast University

Ion specificity of Na＋ and C1- ions for NaCI solution confined in silicon nanochannels is investigated with molecular dynamics （MD） simulations. The MD simulation results demonstrate that ion specificity for Na＋ and C1- ions exhibits clearly in na- nochannels with high surface charge density. The two types of ions show different density distributions perpendicular to the channel surface due to the ion specificity when they act as countefions near negatively and positively charged surfaces, respec- tively. Both the two counterion distributions cannot be predicted by Poisson-Boltzmann equation within 0.75 nm near the sur- face. In addition, the ion specificity is also demonstrated through affecting the water density distributions. In the nanochannel with negatively charged surfaces, the presence of the Na＋ ions reduces the number of water peaks in water density distribution profile. In comparison, when the C1- ions act as counterions near positively charged surfaces, they do not affect the number of the water peaks. Besides the influence on the water density distribution, ion specificity also exhibits through affecting the wa- ter molecule orientation in the adsorbed layer. It is found that C1- ions make the water molecules in the adsorbed layer align more orderly than Na~ ions do when the two types of ions act as the counterions near the positively and negatively charged surfaces with the same surface charge density.

关键词： ion specificity molecular dynamics simulations nanochannel Poisson-Boltzmann equation electrical double layer

沟灌不同灌溉定额对盐渍土水盐分布及油葵和产量的影响

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节水灌溉 2019年第10期 26-30页

作者：斯庆高娃内蒙古机电职业技术学院水利与土木建筑工程系

为研究沟灌对甘肃盐渍土垄顶与垄沟土壤水盐的影响,在统一起垄、沟灌的基础上,设置3个梯度的灌溉定额:6 600 m^3/hm^2(T1)、7 200 m^3/hm^2(T2)、7800 m^3/hm^2(T3)。通过田间定位试验研究不同灌溉定额对盐渍土含水率、含盐量及盐分离... 详细信息

为研究沟灌对甘肃盐渍土垄顶与垄沟土壤水盐的影响,在统一起垄、沟灌的基础上,设置3个梯度的灌溉定额:6 600 m^3/hm^2(T1)、7 200 m^3/hm^2(T2)、7800 m^3/hm^2(T3)。通过田间定位试验研究不同灌溉定额对盐渍土含水率、含盐量及盐分离子的影响。试验结果表明:沟灌有助于在垄沟内蓄积水分,将沟内表层土壤盐分控制在较低水平,0~60 cm土层垄沟内土壤含水率比垄顶平均高19.6%、土壤含盐量比垄顶平均低21.8%;随灌水定额增加土壤盐分降低明显;虽然T3处理下油葵的产量最高(2.51 t/hm^2),但T2处理下油葵的水分生产率最高(16.22 kg/m^3)。试验区地处我国西北干旱区,农业水资源有限,灌水量过多不利于提高水分生产率还会增加发生次生盐渍化的风险,因此,沟灌灌溉定额为7 200 m^3/hm^2适宜于改良该地区盐渍土。

关键词：沟灌起垄含水率含盐量产量

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基于最大流增流关键边的疏散逆向路段优化

交通运输系统工程与信息 2016年第3期16卷 194-199页

作者：高明霞洪娃艺司倩倩兰州交通大学交通运输学院兰州730070

逆向车道作为提高路网疏散通行能力的一种交通组织方法,已在疏散交通组织中得到了广泛应用.本文采用网络优化技术,研究疏散交通组织中逆向车道设置路段的选择问题.将道路网抽象为有向网络,给出网络最大流增流关键边的定义,通过寻找网络... 详细信息

逆向车道作为提高路网疏散通行能力的一种交通组织方法,已在疏散交通组织中得到了广泛应用.本文采用网络优化技术,研究疏散交通组织中逆向车道设置路段的选择问题.将道路网抽象为有向网络,给出网络最大流增流关键边的定义,通过寻找网络最大流增流关键边、次关键边等,确定路网中实行逆向车道管理的备选路段.在求解最大流问题的最大容量路算法基础上,给出了在有向网络中寻找最大流增流关键边的改进算法,通过一个数值算例进行分析,并对计算结果进行仿真验证.结果表明,在产生大量交通需求的大规模交通疏散中,通过对最大流增流关键边所对应路段进行逆向管理扩容,能够有效压缩疏散时间.

关键词：城市交通逆向路段选择最大流增流关键边交通疏散改进算法

In situ TiC/FeCrNiCu High-Entropy Alloy Matrix Composites:Reaction Mechanism,Microstructure and Mechanical Properties

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Acta Metallurgica sinica(English Letters) 2020年第8期33卷 1091-1102页

作者： Hao Wu si-Rui Huang Cheng-Yan Zhu Ji-Feng Zhang He-guo Zhu Zong-Han Xie College of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Mechanical Engineering University of AdelaideSA 5005Australia School of Engineering Edith Cowan UniversityJoondalupWA 6027Australia

In situ TiC particles-reinforced FeCrNiCu high-entropy alloy matrix composites were prepared by vacuum induction melting *** reaction mechanisms of the mixed powder(Ti,Cu and C)were analyzed,and the mechanical properties of resultant composites were ***4Tiwere formed in the reaction of Cu and Ti when the temperature rose to 1160 *** the temperature further increased to 1182 K,newly formed Cu4Tireacted with C to give rise to TiC particles as reinforcement *** apparent activation energy for these two reactions was calculated to be 578.7 kJ/mol and 1443.2 kJ/mol,*** hardness,tensile yield strength and ultimate tensile strength of the 15 vol%TiC/FeCrNiCu composite are 797.3 HV,605.1 MPa and 769.2 MPa,respectively,representing an increase by 126.9%,65.9%and 36.0%as compared to the FeCrNiCu high-entropy base alloy at room ***,the elongation-to-failure is reduced from 21.5 to 6.1%with the formation of TiC *** was revealed that Orowan mechanism,dislocation strengthening and load-bearing effect are key factors responsible for a marked increase in the hardness and strength of the high-entropy alloy matrix composites.

关键词： High-entropy alloy matrix composite TiC particle Reaction mechanism Mechanical properties Strengthening mechanism

Refractive index insensitive temperature sensor based on waist-enlarged few mode fiber bitapers

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Optoelectronics Letters 2017年第1期13卷 25-28页

作者： LIU Qiang wa.g si-wen FU Xing-hu FU guang-wei JIN wa BI Wei-hong The Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science.and Engineering Yanshan University Qinhuangdao 066004 China

A refractive index insensitive temperature sensor based on waist-enlarged few mode fiber(FMF) bitapers is presented. The first section of FMF is spliced between two single-mode fibers. In fusion process,the waist-enlarged FMF bitapers can be obtained by large current discharging repeatedly. The refractive index and temperature sensing mechanisms are analyzed. For the sensors with different sizes,the refractive index and temperature experiments have been performed. The results show that in the refractive index ranges of 1.335 0—1.346 6 and 1.348 2—1.419 3,the refractive index insensitivity is verified. In a temperature range of 31.9—90 °C,the sensor sensitivity can be up to 85.57 pm/°C. In addition,it has a compact structure. Therefore,the sensor can avoid the cross sensitivity for measuring the refractive index and temperature simultaneously.

关键词： insensitive refractive verified waist sizes enlarged cladding details interferometer repeatedly

High-efficiency plastome base editing in rice with TAL cytosine deaminase

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Molecular Plant 2021年第9期14卷 1412-1414页

作者： Riqing Li si Nian Cha Bo Liu Hua Liu Xianran Li Bing Yang Division of Plant Sciences Bond Life Sciences CenterUniversity of MissouriColumbiaMO 65211USA USDA-ARS Wheat HealthGenetics and Quality Research UnitPullmanWA 99164USA Donald Danforth Plant Science Center St.LouisMO 63132USA

Dear Editor,genome editing has been widely applied in nuclei but not so in organelles such as the mitochondria and *** challenge for organelle genome editing is the limited accessibility of editing reagents to the compartments of organelles(Zhu et al.,2020).Recently,fusion proteins of cytidine deaminase domain(DddAtox)and transcription activator-like effectors(TALEs)have been developed for DNA base editing in mitochondria of human cells and mice(Mok et al.,2020;Lee et al.,2021).

关键词： base editing organelle