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Advances in Atmospheric Sciences 2017年第5期34卷 587-598页

作者： yihui liu Yetang WANG Minghu DING Weijun SUN Tong ZHANG Yuetong XU College of Geography and Environment Shandong Normal University Institute of Climate System Chinese Academy of Meteorological Sciences

Recent snow height measurements(2008–15) from nine automatic weather stations(AWSs) on the Ross Ice Shelf are used to examine the synoptic and seasonal variability in snow accumulation,and also to evaluate the performance of the Antarctic Mesoscale Prediction System(AMPS) for precipitation. The number of snow accumulation events varies from one station to another between 2008 and 2015,thus demonstrating geographic dependence. The interannual variability in snow accumulation is too high to determine its seasonality based on the current AWS observations with limited time *** between the AMPS and AWS snow height measurements show that approximately 28% of the AWS events are reproduced by AMPS. Furthermore,there are significant correlations between AMPS and AWS coincident event sizes at five stations(p < 0.05). This finding suggests that AMPS has a certain ability to represent actual precipitation events.

关键词： snow accumulation measurements precipitation evaluation Ross Ice Shelf

Functional ceramic support as an independent catalyst layer for direct liquid fuel solid oxide fuel cells

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Journal of Advanced Ceramics 2023年第3期12卷 474-486页

作者： Jie Luo Kai Zhao Jishi Zhao Jun Li yihui liu Dongchu Chen Qing Xu Min Chen School of Materials Science and Hydrogen Energy Foshan UniversityFoshan 528000China Guangdong Key Laboratory for Hydrogen Energy Technologies Foshan UniversityFoshan 528000China Foshan Institute of Environment and Energy Technology Foshan 528000China R&D Center of Hydrogen Energy Standardization Yunfu 527300China Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

A porous ceramic support is designed as a multi-functional independent catalyst layer for solid oxide fuel cells(SOFCs)running on liquid hydrocarbon *** layer consists of a highly porous Ce_(0.9)Ca_(0.1)O_(2−δ)ceramic backbone and active NiMo catalysts,which could be integrated into the conventional Ni metal containing the anode for internal reforming of the hydrocarbon *** to conventional catalyst layers sintered on the anodes,this independent catalyst layer could be simply assembled on top of the anode without additional sintering,thereby avoiding the mismatch of the thermal expansion coefficient between the catalyst layer and the anode and improving stability of a single ***,a current collector layer could be inserted between the catalyst and the anode to enhance current collection efficiency and electrochemical performance of the single *** 750℃,the independent catalyst layer displays high activity towards the catalytic decomposition of methanol,and the single cell could achieve the maximum power density of 400–500 mW·cm^(−2)in dry ***,by employing the independent catalyst layer,the single cell offers additional in-situ catalyst regeneration capability under the methanol operation *** 10 mL·min−1 air into an anode channel for 5 min is found to be effective to burn out carbon species in the catalyst layer,which reduces the degradation rate of the cell voltage by orders of magnitude from 2.6 to 0.024 mV·h−1 during the operation of 360 h in dry *** results demonstrate the significance of the independent catalyst layer design for direct internal reforming methanol fuel cells.

关键词： independent catalyst layer NiMo-Ce_(0.9)Ca_(0.1)O_(2−δ)catalyst internal reforming methanol solid oxide fuel cell(SOFC)

Molecular detection of porcine circovirus type 3 in Shanxi Province,China

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Animal Diseases 2021年第2期1卷 116-124页

作者： Weidong Yue yihui liu Xinrong Zhang Haili Ma Junping He College of Veterinary Medicine Shanxi Agricultural UniversityTaiguShanxi 030801People's Republic of China

Porcine circovirus type 3(PCV3),which was first detected in the United States of America in 2015,is a potential threat to the swine ***,the prevalence of PCV3 in Shanxi Province,China,is *** this research,the prevalence and genetic diversity of PCV3 were investigated in above *** tissue samples(n=491)from 19 pig slaughterhouses across 11 cities throughout Shanxi Province were analyzed for PCV3 infection by PCR in *** results showed that PCV3 positive rates in slaughterhouses and individuals were 100%(19/19)and 86.76%(426/491),***2 and PCV3 double-positive rates in slaughterhouses and individuals were 100%(19/19)and 59.27%(291/491),*** positive samples were further sequenced and 8 PCV3 isolates were *** nucleotide homology of these isolates with other PCV3 isolates in NCBI database was 97.45-99.90%.A phylogenetic analysis,based on the complete genomic sequence and ORF2,divided these PCV3 strains into 2 major *** on A24A/and R27/K amino acid mutations of capsid protein,the 8 identified PCV3 strains were separated to 2 *** was the first detailed investigation into the epidemiology of PCV3 in Shanxi *** findings enabled us to assess the possibility of widespread transmission from this ***,current findings establish a basis for further studies of genetic variations in PCV3 strains circulating in China.

关键词： Circovirus Prevalence Porcine circovirus type 3(PCV3) Phylogenetic analysis

Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics

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Journal of Integrative Agriculture 2024年第5期23卷 1749-1762页

作者： Xiabing Kong Qiusheng Chen Min Xu yihui liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu liu Xubo Zhao Jiyun Nie College of Horticulture Qingdao Agricultural University/Laboratory of Quality&Safety Risk Assessment for Fruit(Qingdao)Ministry of Agriculture and Rural Affairs/National Technology Centre for Whole Process Quality Control of FSEN Horticultural Products(Qingdao)/Qingdao Key Lab of Modern Agriculture Quality and Safety EngineeringQingdao 266109China Institute of Agricultural Product Quality Safety and NutritionTianjin Academy of Agricultural SciencesTianjin 300381China College of Food Science and Engineering Northwest A&F UniversityYangling 712100China

Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the ***,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing *** linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,*** using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,*** on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter ***,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits.

关键词： winter jujube multi-element fingerprint analysis chemometrics origin traceability

Prominent feature selection of microarray data

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Progress in Natural Science:Materials International 2009年第10期19卷 1365-1371页

作者： yihui liu School of Computer Science and Information Technology,Shandong Institute of Light Industry,Jinan 250353,China School of Computer Science and Information Technology Shandong Institute of Light Industry Jinan 250353 China

For wavelet transform,a set of orthogonal wavelet basis aims to detect the localized changing features contained in microarray *** this research,we investigate the performance of the selected wavelet features based on wavelet detail coefficients at the second level and the third *** genetic algorithm is performed to optimize wavelet detail coefficients to select the best discriminant *** are carried out on four microarray datasets to evaluate the performance of *** results prove that wavelet features optimized from detail coefficients efficiently characterize the differences between normal tissues and cancer tissues.

关键词： Microarray data Wavelet detail coefficients Feature extraction Feature selection

Doping strategy on improving the overall cathodic performance of double perovskite LnBaCo_(2)O_(5+σ)(Ln=Pr,Gd)as potential SOFC cathode materials

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Journal of Materiomics 2023年第5期9卷 825-837页

作者： Fangze Chen Dacheng Zhou Xueqing Xiong Juntao Pan Donglin Cai Ze Wei Xiyong Chen yihui liu Nengneng Luo Jialin Yan Toyohisa Fujita State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning530004GuangxiChina School of Resources Environment and MaterialsGuangxi UniversityNanning530004GuangxiChina Hubei Key Laboratory of Advanced Technology for Automotive Components&Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan430070HubeiChina

A series of single-phase double perovskite Pr1-xGdxBaCo_(2)-yFeyO_(5+σ)(x=0,0.5 and 1,0≤y≤1)materials were engineered through A/B site co-doping strategy to improve the mechanical,electrical and electrochemical properties as potential cathode materials for the application of intermediate solid oxide fuel cells(IT-SOFCs).The corresponding thermochemical stability,thermal expansion behavior,electrical conductivity and cathodic polarization resistance of the materials were systematically *** was found that the A-site dual lanthanide doped Pr_(0.5)Gd_(0.5)BaCo_(2)O_(5+σ)(PGBCO)exhibits improved electrical conductivity,reduced thermal expansion,and comparatively low electrochemical polarization resistance versus single lanthanide double perovskite,PrBaCo_(2)O_(5+σ)(PBCO)and GdBaCo_(2)O_(5+σ)(GBCO)*** investigation on the effect of B-site Fe-doping on Pr_(0.5)Gd_(0.5)BaCo_(2)-yFeyO_(5)+σ(PGBCF-y,0≤y≤1)reveals that all the PGBCF-y compositions exhibit excellent chemical stability with Gd-doped ceria(GDC)at operating temperatures not higher than 1100℃.Besides,doping of Fe in B-site can effectively reduce the thermal expansion coefficients(TECs)of the Pr_(0.5)Gd_(0.5)BaCo_(2)O_(5)+σceramics at 30e1000℃.And the electrochemical impedance spectra(EIS)results show that the PGBCF-y|GDC|PGBCF-y symmetric cells have acceptable low area specific polarization *** examination of the cathodic polarization and characteristic capacitance from the AC impedance spectra by employing the relaxation time distribution(DRT)method demonstrated that charge transfer is the dominating subprocess for the oxygen transport through the materials.

关键词： Double perovskite Electrical conductivity Thermal expansion Electrochemical polarization Thermochemical stability

Individual aortic baroreceptors are sensitive to different ranges of blood pressures

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Science China(Life Sciences) 2014年第7期57卷 502-509页

作者： CHEN MengJiao YANG MingHao HAN WenJuan AN ShuCheng liu yihui liu ZhiQiang REN Wei MOE Key Laboratory for Modern Teaching Technology and College of Life Sciences Shaanxi Normal University

Many receptors,including thermal receptors and mechanical receptors,are only activated by stimuli within a clearly defined range of *** in the receptive ranges enable individual receptors and their sensory centers to precisely detect the intensity of the stimulus and changes in *** are the sensory terminals of the *** is well understood that an increasing number of baroreceptors are recruited to produce afferent action potentials as the blood pressure increases,indicating that individual baroreceptors have different pressure *** present study revealed that individual baroreceptors could stop their afferent signals when the blood pressure exceeds a certain level,indicating that individual baroreceptors are sensitive to a specific range of blood *** receptive ranges of individual baroreceptors differ in terms of the total range,the lower threshold,and the upper *** 85 baroreceptors examined in this study,the upper thresholds for about half were within the physiological blood pressure *** results indicate that supraphysiological blood pressure is unlikely to be encoded by the recruitment of more ***,supraphysiological blood pressure levels might be signaled by an increase in the frequency of action potentials or by other *** conclusion,our results indicate that rabbit baroreceptors are activated by blood pressure levels within specific receptive *** findings should encourage further studies to examine the role of population coding of blood pressure by baroreceptors in the baroreflex.

关键词： depolarization block receptive range rabbit depressor nerve single fiber recording

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市场竞争程度、研发投入和中小科技企业创新产出一一基于风险投资调节的条件过程分析

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中国软科学 2021年第10期 182-192页

作者：宋清刘奕惠天津科技大学经济与管理学院天津300457

中小科技企业的创新发展对于促进国家创新战略的实施至关重要。风险投资作为"高能资本",是提高中小科技企业创新产出和增加研发投入的重要手段。本文以2007-2019年中小板和创业板的科技企业作为样本,使用Hayes提出的"条件过程模型"替代... 详细信息

中小科技企业的创新发展对于促进国家创新战略的实施至关重要。风险投资作为"高能资本",是提高中小科技企业创新产出和增加研发投入的重要手段。本文以2007-2019年中小板和创业板的科技企业作为样本,使用Hayes提出的"条件过程模型"替代传统的有调节的中介模型,基于风险投资的调节作用对市场竞争程度影响中小科技企业创新产出进行了条件过程分析。实证研究发现:市场竞争程度通过研发投入的中介作用对企业创新产出产生抑制作用,风险投资可以调节条件过程模型中的每一个路径来促进企业的创新产出。按地区和规模对样本进行分类研究发现,不同地区和不同规模的中小科技企业创新产出的外部因素市场竞争程度和内部因素研发投入及风险投资的影响机制是有区别的。研究结论为中小科技企业的决策、风险投资公司的投资以及国家相关政策的调整提供启示和借鉴。

关键词：中小科技企业市场竞争程度创新产出条件过程模型

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不同取向双晶粒结构材料的蠕变行为分析

航空动力学报 2022年第10期37卷 2201-2212页

作者：刘怡慧王延荣魏大盛北京航空航天大学能源与动力工程学院北京100191 北京航空航天大学江西研究院南昌330096

基于一种宏观唯象模型编写有限元子程序,模拟了双晶粒结构材料的蠕变变形行为。所选取的蠕变模型具有明确的物理意义,模型中的3项分别描述了蠕变演化过程的3个阶段。通过模拟双晶粒结构蠕变变形行为,分析了铸造结构中的偏离角、二次取... 详细信息

基于一种宏观唯象模型编写有限元子程序,模拟了双晶粒结构材料的蠕变变形行为。所选取的蠕变模型具有明确的物理意义,模型中的3项分别描述了蠕变演化过程的3个阶段。通过模拟双晶粒结构蠕变变形行为,分析了铸造结构中的偏离角、二次取向及晶界对定向结晶材料蠕变变形行为的影响;同时,利用坐标系的两次旋转,模拟材料的铸造偏离角和二次取向;通过改变晶界的倾斜角度,模拟材料的小角度倾斜晶界。结果表明:铸造偏离角会明显降低材料的蠕变性能,但二次取向对材料蠕变行为影响较小,晶界的倾斜角度使晶界附近材料的蠕变行为产生明显变化。

关键词：双晶粒结构蠕变行为铸造偏离角二次取向倾斜晶界

Co3O4/β-MnO2/C纳米复合材料的ORR性能研究

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华中科技大学学报（自然科学版） 2020年第10期48卷 57-62页

作者：魏明锐黄硕刘毅辉武汉理工大学现代汽车零部件技术湖北省重点实验室湖北武汉430070 武汉理工大学汽车零部件技术湖北省协同创新中心湖北武汉430070

分别以液相沉淀法、水热法制备Co3O4和β-MnO2,并用超声法制备复合材料Co3O4/β-MnO2/C,将其作为燃料电池阴极催化剂,在三电极体系下研究其催化氧还原反应(ORR)的性能.制备过程中形成了Co3O4纳米颗粒和β-MnO2纳米棒,在Co3O4/β-MnO2/C... 详细信息

分别以液相沉淀法、水热法制备Co3O4和β-MnO2,并用超声法制备复合材料Co3O4/β-MnO2/C,将其作为燃料电池阴极催化剂,在三电极体系下研究其催化氧还原反应(ORR)的性能.制备过程中形成了Co3O4纳米颗粒和β-MnO2纳米棒,在Co3O4/β-MnO2/C中,Co3O4附着在β-MnO2上.采用循环伏安测试(CV)和线性扫描伏安测试(LSV)研究了所制备复合材料的电化学性能,结果表明:由于Co3O4与β-MnO2的协同效应,因此Co3O4/β-MnO2/C在碱性体系中具有良好的催化活性,起始电位达0.88 V、半波电位为0.77 V,极限电流密度为52.4 A·m^-2,催化过程以4电子反应为主.

关键词：燃料电池纳米复合材料活性位点电催化剂氧还原反应