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Transportation Safety and Environment 2024年第2期6卷 96-103页

作者： Chaoqun Xiang Ziyin Fan songyang jiang Xinan Zhang Shu Cheng School of Traffic and Transportation Engineering Central South UniversityChangsha 410075HunanChina CRRC Dalian Electric Traction R&D Center Co. LtdDalian 116200LiaoningChina School of Engineering The University of Western AustraliaPerthWA 6009Australia

The four-level active neutral point clamped(ANPC)inverter has become increasingly widely used in the renewable energy indus-try since it offers one more voltage level without increasing the total number of active switches compared to the three-level ANPC *** model predictive current control(MPCC)is a promising control method for multi-level ***,the conven-tional MPCC suffers from high computational complexity and tedious weighting factor tuning in multi-level inverter applications.A low-complexity MPCC without weighting factors for a four-level ANPC inverter is proposed in this *** computational burden and voltage vector candidate set are reduced according to the relationship between voltage vector and neutral point voltage *** proposed MPCC shows excellent steady-state and dynamics performances while ensuring the neutral point voltage *** efficacy of the proposed MPCC is verified by simulation and experimental results.

关键词： four-level active neutral point clamped(ANPC)inverter model predictive current control(MPCC) low complexity without weighting factors

Ethynylene-Linked Oligomers Based on Benzodithiophene:Synthesis and Photoelectric Properties

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Chinese Journal of Chemistry 2014年第4期32卷 298-306页

作者： songyang jiang Yuwen Ma Yingyi Wang Chengyun Wang Yongjia Shen Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and TechnologyShanghai 200237China

Two conjugated ethynyl-linked oligomers,oligo(benzodithiophene-ethynylene-benzothiadiazole)(O1)and oligo(benzodithiophene-ethynylene-carbazole)(O2),were synthesized by Sonogashira coupling *** de-grees of polymerization were 7 and 10,*** photophysical and electrochemical properties were in-vestigated.O1 exhibitd two strong absorption bands at 404 nm and 483 nm,and O2 at 401 nm and 429 *** re-sults of UV-Vis,cyclic voltammetry(CV)and theoretical calculations showed that O1 has a narrower band gap than *** conductivities of O1 and O2 were 1.05×10^(−15) and 6.98×10^(−16) S/cm,respectively,and would increase to 1.23×10^(−10) and 1.05×10^(−10) S/cm after doping with iodine.

关键词： benzodithiophene conjugated polymer Sonogashira reaction photoelectric property conductivity

胰岛素样生长因子2-MRNA结合蛋白2与口腔黏膜黑色素瘤患者病理特征和预后的关系

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中华实验外科杂志 2023年第12期40卷 2570-2573页

作者：蒋松阳驻马店市中心医院口腔颌面外科驻马店463000

目的探讨胰岛素样生长因子2-MRNA结合蛋白2(IGF2BP2)表达变化及其与患者临床病理特征和预后的关系。方法选取驻马店市中心医院收治的口腔黏膜黑色素瘤患者75例,取病理检测的肿瘤组织和癌旁正常组织,采用免疫组织化学法检测IGF2BP2蛋白表... 详细信息

目的探讨胰岛素样生长因子2-MRNA结合蛋白2(IGF2BP2)表达变化及其与患者临床病理特征和预后的关系。方法选取驻马店市中心医院收治的口腔黏膜黑色素瘤患者75例,取病理检测的肿瘤组织和癌旁正常组织,采用免疫组织化学法检测IGF2BP2蛋白表达,分析肿瘤组织IGF2BP2蛋白表达与患者临床临床病理学的关系。随访3年,统计生存情况,分析肿瘤组织IGF2BP2蛋白表达水平与患者3年生存率的关系。计数资料比较采用卡方检验。结果癌旁组织IGF2BP2蛋白表达阳性率[17.33%(13/75)]明显低于口腔黏膜黑色素瘤组织[82.67%(62/75)],差异有统计学意义(χ^(2)=15.254,P0.05)。年龄≥40岁患者IGF2BP2蛋白表达阳性率[80.49%(33/41)]与女性患者肿瘤组织[82.35%(28/34)]比较,差异无统计学意义(χ^(2)=0.807,P>0.05)。肿瘤直径≥4 cm患者IGF2BP2蛋白表达阳性率[81.40%(35/43)]与肿瘤直径0.05)。发病于牙龈患者IGF2BP2蛋白表达阳性率[80.85%(38/47)]与女性患者肿瘤组织[85.71%(24/28)]比较,差异无统计学意义(χ^(2)=0.681,P>0.05)。Ⅰ~Ⅱ期患者IGF2BP2蛋白表达阳性率[76.19%(32/42)]低于Ⅲ~Ⅳ期患者肿瘤组织[90.91%(30/33)]比较,差异有统计学意义(χ^(2)=4.281,P<0.01)。未淋巴结转移患者IGF2BP2蛋白表达阳性率[70.27%(26/37)]与女性患者肿瘤组织[94.74%(36/38)]比较,差异有统计学意义(χ^(2)=8.991,P<0.01)。IGF2BP2低表达患者3年生存率[84.61%(11/13)]明显高于IGF2BP2高表达患者[54.84%(34/62)],差异有统计学意义(χ^(2)=12.984,P<0.01)。单因素回归分析结果显示临床分期、淋巴结转移和IGF2BP2表达水平与口腔黏膜黑色素瘤患者预后有关(r=0.254、0.514、0.198,P均<0.05)。多因素Cox回归模型结果显示IGF2BP2表达水平高表达是口腔黏膜黑色素瘤患者不良预后的危险因素(P<0.05)。结论口腔黏膜黑色素瘤组织中IGF2BP2蛋白高表达,与肿瘤临床分期和淋巴结转移等临床病理学特征和预后密切相关。

关键词：胰岛素样生长因子2-MRNA结合蛋白2 口腔黏膜黑色素瘤临床病理特征预后

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虚拟零矢量的三相四开关中点电位不平衡研究

铁道科学与工程学报 2018年第2期15卷 497-505页

作者：姜宋阳成庶向超群中南大学信息科学与工程学院湖南长沙410075

三相四开关逆变为三相六开关是逆变的一种低成本控制方案,而三相四开关逆变器存在转矩脉动大、中点电位不平衡的问题。国内外学者对于三相四开关提出了很多控制方法,能够有效地减小电机的转矩脉动问题,但都未能有效地解决电容中点电位... 详细信息

三相四开关逆变为三相六开关是逆变的一种低成本控制方案,而三相四开关逆变器存在转矩脉动大、中点电位不平衡的问题。国内外学者对于三相四开关提出了很多控制方法,能够有效地减小电机的转矩脉动问题,但都未能有效地解决电容中点电位的问题。若不考虑电容中点电位补偿问题,则会导致SVM DTC效果变差,影响三相电流的平衡性,增大电机的转矩脉动,严重情况下还会导致停机。从三相四开关逆变器的基本矢量分析,提出一种新的电容电压补偿方案,并与目前的补偿算法进行比较分析和仿真与实验验证,表明通过本文算法补偿后的电机运行具有较好的性能。

关键词：三相四开关逆变器 SVM DTC 中点电位补偿

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电力机车牵引变流器接地检测电路优化

铁道科学与工程学报 2022年第6期19卷 1786-1793页

作者：姜宋阳任宝珠周鹏李韵楠中车大连电力牵引研发中心有限公司辽宁大连116200

针对现有电力机车接地检测回路,当出现牵引变压器二次侧同名端接地的故障工况时,在主断路器闭合及牵引变流器启动前,电力机车的牵引变流器直流母线会出现异常充电现象,形成严重的安全隐患。为解决该故障工况下的直流母线异常充电问题,... 详细信息

针对现有电力机车接地检测回路,当出现牵引变压器二次侧同名端接地的故障工况时,在主断路器闭合及牵引变流器启动前,电力机车的牵引变流器直流母线会出现异常充电现象,形成严重的安全隐患。为解决该故障工况下的直流母线异常充电问题,在牵引控制单元发脉冲前,通过对该故障工况下的接地检测回路进行电路原理分析,查找直流母线异常充电的原因。针对直流母线异常充电的原因,对现有牵引变流器的接地检测回路进行电路优化。搭建半实物仿真平台,将优化后的接地检测回路通过半实物仿真平台进行验证,监控直流母线在该故障工况下是否出现异常充电现象。经过半实物仿真验证,优化后的电力机车接地检测回路在该故障工况下不会出现直流母线异常充电的现象,且使用该接地检测优化电路,牵引控制单元的接地检测算法无需更改。接地检测回路的优化改造,能够有效地解决电力机车直流母线异常充电问题,有效地提高牵引变流器的安全性和稳定性,并且该优化电路结构简单、易于实现,具备较高的推广应用价值。

关键词：牵引变流器接地检测回路异常充电半实物仿真

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

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Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao LI Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

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Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun Ye Weiheng Chen Zhong-Jie jiang Zhongqing jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation

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Communications in Theoretical Physics 2024年第5期76卷 33-48页

作者： DongZhu jiang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 01022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is *** and rogue waves can be obtained from this determinant,*** to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different *** addition,the form of the obtained solutions is summarized.

关键词： double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： Hao DING Weiping jiang School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophysical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify and analyze the unidentified decadal signals inherent in the GPS displacements. In this research, we employ the optimal sequence estimation method to effectively detect an about 13.6-year oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy that this signal demonstrates a consistent spatial pattern characterized by the spherical harmonic Y_(2,-2). We conduct a comparative analysis with the 13.6-year oscillation observed in length-of-day variations(and geomagnetic records), finding that they are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hydrological records, we suggest that the 13.6-year GPS signal may come from the internal motions within the Earth. However, the specific excitation source and the detailed physical mechanism remain uncertain. Additionally, we develop a mathematical displacement model to explain the 13.6-year signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity effects of 0.63 mm/yr(for U-component) at maximum. These results underscore the necessity of incorporating this 13.6-year signal into the construction and maintenance of a dynamic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-year oscillation Displacement model Dynamic reference frame