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Recent progress on nanostructured bimetallic electrocatalysts for water splitting and electroreduction of carbon dioxide

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Journal of Semiconductors 2020年第9期41卷 59-77页

作者： Can cui Xiaosong Hu Liaoyong Wen Department of Materials Science and Engineering&Institute of Materials Science University of ConnecticutStorrsConnecticut06269-3136United States of America Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China

The exploitation of renewable energy as well as the elimination of the harmful impact of excessive carbon emission are worldwide concerns for sustainable development of the ecological environment on *** address that,the technologies regarding energy conversion systems,such as water splitting and electroreduction of carbon dioxide,have attracted significant attention for a few ***,to date,the production of green fuels and/or high energy density chemicals like hydrogen,methane,and ethanol,are still suffering from many drawbacks including high energy consumption,low selectivity,and sluggish reaction *** this regard,nanostructured bimetallic materials that is capable of taking the full benefits of the coupling effects between different elements/components with structure modification in nanoscale are considered as a promising strategy for high-performance ***,this review aims to outline the important progress of these nanostructured bimetallic *** starts with the introduction of some important fundamental background knowledge about the reaction mechanism to understand how these reactions ***,we summarize the most recent progress regarding how the nanostructured bimetallic electrocatalysts manipulate the activity and selectivity of catalytic reactions in the order of bimetallic alloying effect,interface/substrate effect of bi-component electrocatalyst,and nanostructuring effect.

关键词： bimetallic electrocatalysts nanostructures water splitting electroreduction of carbon dioxide

蝴蝶兰DREB基因家族鉴定及非生物胁迫表达分析

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农业生物技术学报 2024年第8期32卷 1715-1728页

作者：胡子昂罗平辛静静崔永一浙江农林大学园艺科学学院

脱水响应元件结合蛋白(dehydration responsive element binding, DREB)基因家族在植物响应低温、干旱和高盐等非生物胁迫过程中发挥重要作用，目前对蝴蝶兰(Phalaenopsis spp.) DREB基因家族的相关研究报道较少。本研究基于阿婆蝴蝶兰(... 详细信息

脱水响应元件结合蛋白(dehydration responsive element binding, DREB)基因家族在植物响应低温、干旱和高盐等非生物胁迫过程中发挥重要作用，目前对蝴蝶兰(Phalaenopsis spp.) DREB基因家族的相关研究报道较少。本研究基于阿婆蝴蝶兰(Phalaenopsis aphrodite)基因组数据库，开展了蝴蝶兰DREB家族成员的全基因组鉴定、进化关系分析、生物信息学分析、亚细胞定位和在低温、干旱、高盐3种非生物胁迫及脱落酸(abscisic acid, ABA)处理下的基因表达模式分析。结果显示，在阿婆蝴蝶兰基因组数据库中共鉴定得到了31个DREB家族成员，分为A1～A6共6个亚组；保守基序分析表明，所有PaDREB转录因子均含有1个AP2保守结构域。阿婆蝴蝶兰转录组表达模式分析结果显示，不同PaDREBs呈现组织差异性表达，且多数基因在根部高表达。分离A1亚组4个成员，将其分别命名为：PaDREB1A、PaDREB1B、PaDREB1C和PaDREB1D，亚细胞定位结果表明，其均定位于细胞核。PaDREB1A～PaDREB1D的表达模式分析结果表明，PaDREB1A主要响应干旱、高盐和ABA处理；PaDREB1B主要响应低温和高盐处理；PaDREB1C主要响应干旱和ABA处理；PaDREB1D主要响应低温、干旱和ABA处理。上述结果提示，蝴蝶兰DREB家族在响应非生物胁迫通路中具有重要作用，本研究为后续研究蝴蝶兰DREB家族响应非生物胁迫的作用机理提供理论依据。

关键词：蝴蝶兰脱水响应元件结合蛋白(DREB)转录因子生物信息学分析亚细胞定位非生物胁迫

Variance Variation Criterion and Consistency in Estimating the Number of Significant Signals of High-dimensional PCA

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 513-531页

作者： Guan-peng WANG Heng-jian cui School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

In this paper,we propose a criterion based on the variance variation of the sample eigenvalues to correctly estimate the number of significant components in high-dimensional principal component analysis(PCA),and it corresponds to the number of significant eigenvalues of the covariance matrix for p-dimensional *** the random matrix theory,we derive that the consistent properties of the proposed criterion for the situations that the significant eigenvalues tend to infinity,as well as that the bounded significant population *** simulation shows that the probability of estimator is correct by our variance variation criterion converges to 1 is faster than that by criterion of Passemier and Yao[Estimation of the number of spikes,possibly equal,in the high-dimensional *** Anal.,(2014)](PYC),AIC and BIC under the finite fourth moment condition as the dominant population eigenvalues tend to ***,in the case of the maximum eigenvalue bounded,once the gap condition is satisfied,the rate of convergence to 1 is faster than that of PYC and AIC,especially the effect is better than AIC when the sample size is *** is worth noting that the variance variation criterion significantly improves the accuracy of model selection compared with PYC and AIC when the random variable is a heavy-tailed distribution or finite fourth moment not exists.

关键词： consistency variance variation criterion significant eigenvalues high dimension spiked model

Compact bandpass filter based on two meandered parallel-coupled lines in different lengths

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 33-36页

作者： cui Dong-nuan LIU Yuan-an LI Shu-lan YU cui-ping School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

A new compact bandpass filter based on two meandered parallel-coupled lines of different lengths in shunt is presented, using the signal-interference technique, this filter obtains a low insertion loss and sharp rejection. A set of analytical formulas and guidelines for the design of the bandpass filter are provided in two theoretical analysis methods. According to the number of attenuation poles of the reflection coefficients in the passband, it can be summed up two types of filters. To validated this topology, two wideband bandpass filters centered at 3 GHz are built to verify the theoretical prediction, the measured frequency response of the filter agrees excellently with the predicted result.

关键词： meandered parallel-coupled lines signal-interference technique attenuation poles

空中智能反射面增强的URLLC多无人机网络

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西南交通大学学报 2024年第4期59卷 907-916页

作者：崔亚平应兆朋何鹏郑玉峰吴大鹏王汝言陈烙重庆邮电大学通信与信息工程学院重庆400065 重庆邮电大学先进网络与智能互联技术重庆市高校重点实验室重庆400065 重庆邮电大学泛在感知与互联重庆市重点实验室重庆400065

在多无人机超可靠低时延通信(ultra-reliable low-latency communications,URLLC)网络中,为满足超可靠低时延要求,引入空中智能反射面(intelligent reflecting surface,IRS)辅助通信,提出一种多智能体深度确定性策略梯度(multi-agent deep deterministic policy gradient,MADDPG)方法.首先,建立URLLC多无人机系统模型,其中,多架主无人机作为空中基站为多个地面用户提供服务,一架辅无人机携带IRS作为空中无源中继,辅助主无人机与地面用户通信;然后,考虑多种信道条件和能耗,分别建立复合信道模型和总能耗模型;接着,对问题进行分析,在满足有限块长、无人机能量以及IRS相移的约束下,通过联合优化通信调度、IRS相移以及块长,达到总解码错误率最小化的目标;最后,考虑集中式训练在URLLC场景下的时延敏感限制以及分布式训练在无人机资源限制下的能量限制,设计集中式训练、分布式执行的MADDPG框架.研究结果表明:总解码错误率随着IRS反射单元的增加而急剧下降;同时,总解码错误率随着块长和发射功率的增大而减小,具体来说,块长每增加20个符号,总解码错误率减小91.1%.

关键词：多无人机智能反射面可靠性多智能体

外源AHLs培养下荧光假单胞菌qPCR内参基因的筛选

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中国食品学报 2024年第2期24卷 32-42页

作者：崔方超王芸婷王当丰檀茜倩李秋莹励建荣李婷婷渤海大学食品科学与工程学院、生鲜农产品贮藏加工及安全控制技术国家地方联合工程研究中心、中国轻工业海水鱼加工重点实验室辽宁锦州121013 大连民族大学生命科学学院辽宁大连116600

目的:荧光假单胞菌是冷藏食品的优势腐败菌,其致腐基因受到群体感应系统的调控。为了准确定量腐败基因的表达,研究群体感应调控食品腐败的机制,需筛选荧光假单胞菌的内参基因。方法:以荧光假单胞菌PF-08为研究对象,选择8个常见的内参基... 详细信息

目的:荧光假单胞菌是冷藏食品的优势腐败菌,其致腐基因受到群体感应系统的调控。为了准确定量腐败基因的表达,研究群体感应调控食品腐败的机制,需筛选荧光假单胞菌的内参基因。方法:以荧光假单胞菌PF-08为研究对象,选择8个常见的内参基因(dsbA、carA、rpsL、gyrB、atpD、rpoD、gltA、16S rRNA),添加不同类型群体感应信号分子培养后,利用实时荧光定量PCR(qPCR)技术检测其基因表达量,采用geNorm、Normfinder、BestKeeper和RefFinder综合评估候选内参基因的表达稳定性,筛选最适内参基因。结果:在不同类型外源信号分子培养下,荧光假单胞菌中Ct值变化程度最小的是gltA,16S rRNA的Ct值过低;geNorm分析表达最稳定的内参基因是atpD和rpoD,且二者联用能准确定量目的基因表达水平;Normfinder和BestKeeper的分析结果都显示gltA是最稳定的内参基因;进一步用RefFinder综合评估,内参基因中表达较稳定的是rpoD和gltA。结论:rpoD和gltA在荧光假单胞菌经不同QS信号分子处理后均稳定表达,可用于后续荧光假单胞菌腐败基因的表达研究,也可为研究其它腐败菌的QS相关基因表达提供内参基因参考。

关键词：荧光假单胞菌群体感应实时荧光定量PCR 内参基因

Corrosion Resistance of Superhydrophobic Mg-Al Layered Double Hydroxide Coatings on Aluminum Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1373-1381页

作者： Fen Zhang Chang-Lei Zhang Liang Song Rong-Chang Zeng Lan-Yue cui Hong-Zhi cui College of Materials Science and Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of Sciences

A superhydrophobic surface was successfully constructed to modify the layered double hydroxide （LDH） coatings on aluminum alloy using stearic acid. The characteristics of the coatings were investigated using SEM, XRD, FT- IR and XPS. The corrosion resistance of the prepared coatings was studied using potentiodynamic polarization and electrochemical impedance spectrum. The results revealed that the superhydrophobic surface considerably improved the corrosion-resistant performance of the LDH coatings on the aluminum alloy substrate. The formation mechanism of the superhydrophobic surface was proposed.

关键词： Aluminum alloy Layered double hydroxide Superhydrophobic Stearic acid Corrosion

积极心理健康素养量表在初中生群体中的信效度检验

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中国临床心理学杂志 2024年第4期32卷 893-897页

作者：崔艳雨王春前陈珅王玮李永鑫河南大学心理与行为研究所开封475004 郑州回民高级中学郑州450003

目的:在初中生群体中修订积极心理健康素养量表,检验其信效度。方法:选取443名初中生在时间1施测一般情况问卷、积极心理健康素养量表、专业心理求助态度问卷、简易应对方式量表、广泛性焦虑量表和简版流调中心抑郁量表,并对其中的270... 详细信息

目的:在初中生群体中修订积极心理健康素养量表,检验其信效度。方法:选取443名初中生在时间1施测一般情况问卷、积极心理健康素养量表、专业心理求助态度问卷、简易应对方式量表、广泛性焦虑量表和简版流调中心抑郁量表,并对其中的270名初中生在时间2施测积极心理健康素养量表、孤独感量表和积极心理健康量表。另外选取429名初中生施测积极心理健康素养量表,进行验证性因素分析。结果:(1)探索性因素分析和验证性因素分析均支持积极心理健康素养量表的单维结构;(2)积极心理健康素养量表的α系数和ω系数分别为0.793和0.796(样本1时间1)、0.793和0.800(样本1时间2)、0.833和0.835(样本2),重测信度为0.588(样本1);(3)T1积极心理健康素养与T1家庭经济状况(r=0.147,P<0.01)、积极应对方式(r=0.442,P<0.001)和专业心理求助态度(r=0.281,P<0.001)呈显著正相关,与T1抑郁(r=-0.457,P<0.001)和焦虑(r=-0.341,P<0.001)呈显著负相关;(4)T2积极心理健康素养与T2积极心理健康呈显著正相关(r=0.737,P<0.001),与T2孤独感呈显著负相关(r=-0.538,P<0.001);(5)T1积极心理健康素养与T2积极心理健康呈显著正相关(r=0.526,P<0.001),与T2孤独感呈显著负相关(r=-0.367,P<0.001)。结论:积极心理健康素养量表具有良好的信效度,可以用于以后的相关研究。

关键词：积极心理健康素养效度信度

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From Parametric Representation to Dynamical System: Shifting Views of the Motor Cortex in Motor Control

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Neuroscience Bulletin 2022年第7期38卷 796-808页

作者： Tianwei Wang Yun Chen He cui Center for Excellence in Brain Science and Intlligent Technology Institute of NeuroscienceChinese Academy of SciencesShanghai 200031China Shanghai Center for Brain and Brain-inspired Intelligence Technology Shanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

In contrast to traditional representational perspectives in which the motor cortex is involved in motor control via neuronal preferenceforkinetics andkinematics,a dynamical system perspective emerging in the last decade views the motor cortex as a dynamical machine that generates motor commands by autonomous temporal *** this review,we first look back at the history of the representational and dynamical perspectives and discuss their explanatory power and controversy from both empirical and computational points of ***,we aim to reconcile the above perspectives,and evaluate their theoretical impact,future direction,and potential applications in brain-machine interfaces.

关键词： Dimensionality reduction Neural network Machine learning Population decoding Brain-machine interface