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Journal of Integrative Agriculture 2024年第7期23卷 2164-2177页

作者： Bingli Jiang Wei Gao Yating Jiang shengnan yan Jiajia Cao Litian Zhang Yue Zhang Jie Lu Chuanxi Ma Cheng Chang Haiping Zhang Key Laboratory of Wheat Biology and Genetic Improvement on Southern Yellow&Huai River Valley Ministry of Agriculture and Rural Affairs/College of AgronomyAnhui Agricultural UniversityHefei 230036China

The P-type plasma membrane(PM)H^(+)-ATPases(HAs)are crucial for plant development,growth,and defense.The HAs have been thoroughly characterized in many different plants.However,despite their importance,the functions of HAs in germination and seed dormancy(SD)have not been validated in wheat.Here,we identified 28 TaHA genes(TaHA1-28)in common wheat,which were divided into five subfamilies.An examination of gene expression in strong-and weak-SD wheat varieties led to the discovery of six candidate genes(TaHA7/-12/-14/-16/-18/-20).Based on a single nucleotide polymorphism(SNP)mutation(C/T)in the TaHA7 coding region,a CAPS marker(HA7)was developed and validated in 168 wheat varieties and 171 Chinese mini-core collections that exhibit diverse germination and SD phenotypes.We further verified the roles of the two allelic variations of TaHA7 in germination and SD using wheat mutants mutagenized with ethyl methane sulphonate(EMS)in‘Jimai 22’and‘Jing 411’backgrounds,and in transgenic Arabidopsis lines.TaHA7 appears to regulate germination and SD by mediating gibberellic acid(GA)and abscisic acid(ABA)signaling,metabolism,and biosynthesis.The results presented here will enable future research regarding the TaHAs in wheat.

关键词： wheat P-type plasma membrane H^(+)-ATPase seed dormancy abscisic acid gibberellin

Study on S-shaped region of pump turbine based on Omega vortex analysis method and entropy production theory

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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 102-109,F0003页

作者： Zhenggui Li Hongji Zeng Kun Wang Xiaodong Peng shengnan yan Qin Zhao Key Laboratory of Fluid and Power Machinery Ministry of Education(Xihua University)Chengdu 610039China Key Laboratory of Fluid Machinery and Engineering of Sichuan Province Xihua UniversityChengdu 610039China

In order to comprehensively analyze the operation instability of the pump turbine S-shaped region,this paper uses DDES turbulence model to calculate the model pump turbine from the perspective of the evolution law of runner vortex and draft tube vortex rope and entropy production rate,combined with experiments.The results show that the numerical simulation is in good agreement with the experiment.Omega vortex analysis method is more accurate than other vortex recognition methods because it is not affected by the threshold value.The vortices at the runner region under the runaway condition and the turbine brake condition develop towards the vaneless space and the blade pressure surface respectively,which will cause the flow obstruction and blade separation.The overall vorticity of the reverse pump condition is the largest.The vortex rope of the draft tube under runaway and turbine brake conditions is columnar in shape and has very high rotational strength.The vortex rope under reverse pump conditions is prone to fracture and form scattered vortices,impeding the normal movement of the fluid.The entropy production rate of the spanwise surface near the upper ring and the lower crown is greater than the middle spanwise surface due to the boundary layer effect.And the energy dissipation in the runner under reverse pump conditions is characterized by high at both ends of the runner and low in the middle.The energy dissipation near the wall of the straight cone section of the draft tube is large due to the squeezing effect of the vortex rope on the flow.

关键词： pump turbine S-shaped region vortex analysis method vortex evolution entropy production rate

Ultrafast photocarrier and coherent phonon dynamics in type-II Dirac semimetal PtTe2 thin films probed by optical spectroscopy

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Photonics Research 2022年第3期10卷 653-661页

作者： Peng Suo shengnan yan Ruihua Pu Wenjie Zhang Di Li Jiaming Chen Jibo Fu Xian Lin Feng Miao Shi-Jun Liang Weimin Liu Guohong Ma Department of Physics Shanghai UniversityShanghai 200444China National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

We report the ultrafast photocarrier dynamics and coherent phonon excitation in type-II Dirac semimetal platinum ditelluride(PtTe2)thin films via femtosecond(fs)pump-probe spectroscopy at room temperature.Quantitative analysis revealed that the incoherent electronic relaxation consists of two components:a subpicosecond fast relaxation process and a slow component with a time constant of hundreds of picoseconds(ps).Furthermore,the launch of a coherent acoustic phonon(CAP)in the 20 nm film but absence in the 6.8 nm film uncovers the dominant role of temperature gradient in producing a strain wave.The sound velocity and Young’s modulus in the thick PtTe_(2) are determined to be 1.736 km/s and 29.5 GPa,respectively.In addition,the coherent optical phonon(COP)with a frequency of 4.7 THz corresponding to Te atoms out-of-plane A1g vibration has been well resolved in all films,which is ascribed to displacive excitation of coherent phonon(DECP).The observation of a strong probe-wavelength dependent COP amplitude reveals the resonant feature of the optical excitation-induced atomic displacement in PtTe2.Our findings provide deep insight into the excitation and dynamics of CAP and COP as well as the photocarriers’recovery pathway and lifetimes in PtTe_(2).Our study also demonstrates that the COP spectroscopy is a powerful tool to reveal the modulation of frequency-dependent optical constants induced by atomic vibrations,which may find applications in the fields of optoelectronics and ultrafast photonics.

关键词： coherent phonon excitation

Rotation characteristic and granular temperature analysis in a bubbling fluidized bed of binary particles

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Particuology 2015年第1期13卷 76-88页

作者： Tianyu Wang Yurong He shengnan yan Dong Rip Kim Department of Power Engineering Harbin Institute of Technology Department of Mechanical Engineering Hanyang University

In this work, a discrete particle model （DPM） was applied to investigate the dynamic characteristics in a gas-solid bubbling fluidized bed of binary solid particles. The solid phase was simulated by the hard- sphere discrete particle model. The large eddy simulation （LES） method was used to simulate the gas phase. To improve the accuracy of the simulation, an improved sub-grid scale （SGS） model in the LES method was also applied. The mutative Smagorinsky constant case was compared with the previously published experimental data. The simulation by the mutative Smagorinsky constant model exhibited better agreement with the experimental data than that by the common invariant Smagorinsky constant model. Various restitution coefficients and different compositions of binary solids were investigated to determine their influences on the rotation characteristics and granular temperatures of the particles. The particle translational and rotational characteristic distributions were related to certain simulation parameters.

关键词： Smagorinsky constant Rotational characteristics Binary mixture particles Large eddy simulation Discrete hard sphere mode

Anisotropic metal–insulator transition in strained VO_(2)(B) single crystal

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Chinese Physics B 2024年第6期33卷 56-61页

作者：马泽成闫胜楠刘增霖徐涛陈繁强陈思成曹天俊孙立涛程斌梁世军缪峰 Institute of Brain-Inspired Intelligence National Laboratory of Solid State MicrostructuresSchool of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjing 210096China Institute of Interdisciplinary of Physical Sciences School of ScienceNanjing University of Science and TechnologyNanjing 210094China

Mechanical strain can induce noteworthy structural and electronic changes in vanadium dioxide, imparting substantial scientific importance to both the exploration of phase transitions and the development of potential technological applications. Unlike the traditional rutile(R) phase, bronze-phase vanadium dioxide [VO_(2)(B)] exhibits an in-plane anisotropic structure. When subjected to stretching along distinct crystallographic axes, VO_(2)(B) may further manifest the axial dependence in lattice–electron interactions, which is beneficial for gaining insights into the anisotropy of electronic transport.Here, we report an anisotropic room-temperature metal–insulator transition in single-crystal VO_(2)(B) by applying in-situ uniaxial tensile strain. This material exhibits significantly different electromechanical responses along two anisotropic axes.We reveal that such an anisotropic electromechanical response mainly arises from the preferential arrangement of a straininduced unidirectional stripe state in the conductive channel. This insulating stripe state could be attributed to the in-plane dimerization within the distorted zigzag chains of vanadium atoms, evidenced by strain-modulated Raman spectra. Our work may open up a promising avenue for exploiting the anisotropy of metal–insulator transition in vanadium dioxide for potential technological applications.

关键词： vanadium dioxide strain anisotropy electrical transport

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磁性液体性能及运行工况对密封耐压值的影响

润滑与密封 2024年第5期49卷 129-135页

作者：陈芳张杰李正贵李望旭邓波闫盛楠颜招强西华大学能源与动力工程学院四川成都610039 西华大学流体及动力机械教育部重点实验室四川成都610039 自贡兆强密封制品实业有限公司四川自贡643020

为研究不同种类磁性液体及密封工况对密封效果的影响,以Fe_(3)O_(4)为磁性颗粒,以链状氟醚油为基液,制备一系列不同颗粒含量、基液分子量的磁性液体,对磁性颗粒及磁性液体的结构、性能进行表征,在搭建的密封试验台上测试磁性液体种类及... 详细信息

为研究不同种类磁性液体及密封工况对密封效果的影响,以Fe_(3)O_(4)为磁性颗粒,以链状氟醚油为基液,制备一系列不同颗粒含量、基液分子量的磁性液体,对磁性颗粒及磁性液体的结构、性能进行表征,在搭建的密封试验台上测试磁性液体种类及运行工况对密封耐压效果的影响。结果表明:制备的磁性颗粒粒径为纳米级,呈近球形形貌,具有较高的饱和磁化强度,磁性液体具有较好的分散稳定性;随颗粒含量增加、基液分子量增大,密封耐压值先增大后减小;在颗粒质量分数为30%、基液分子量为4600 g/mol时,密封耐压值最高;随主轴转速增大,密封耐压值逐渐减小;随密封时间延长,密封耐压值先减小后趋于稳定。

关键词：磁性液体密封耐压值饱和磁化强度密封寿命分散稳定性

神经外科患者术后谵妄发生率及危险因素的Meta分析

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中国护理管理 2024年第6期24卷 892-897页

作者：陈丽玲康月明严胜男杨辛茹方艳林蓉金福建医科大学附属第一医院神经外科福州市350005 福建医科大学附属第一医院护理部福州市350005 福建医科大学护理学院

目的:通过Meta分析明确神经外科患者术后谵妄的发生率及相关危险因素,为临床早期识别和术后谵妄预防提供依据。方法:计算机检索中、英文数据库中关于神经外科术后谵妄发生率及影响因素的文献,检索时限为建库至2023年6月。对文献进行质... 详细信息

目的:通过Meta分析明确神经外科患者术后谵妄的发生率及相关危险因素,为临床早期识别和术后谵妄预防提供依据。方法:计算机检索中、英文数据库中关于神经外科术后谵妄发生率及影响因素的文献,检索时限为建库至2023年6月。对文献进行质量评价,数据提取后采用Stata 15.0软件进行统计分析。结果:共纳入24篇文献,提取出20项影响因素进行Meta合并。Meta分析结果显示,神经外科患者术后谵妄发生率为24%。年龄、性别、焦虑或抑郁、肿瘤直径、肿瘤性质、高血压史、术前脑缺血、术后GCS评分、术后双额积气、低蛋白血症、低血氧饱和度、发热、睡眠障碍、额下入路术式、使用苯二氮卓类药物及身体约束是神经外科术后谵妄发生的危险因素。结论:神经外科患者术后谵妄发生率较高,临床医护人员应加强对谵妄的监测和管理,根据相关危险因素早期识别高危人群并进行有针对性的预防和控制。

关键词：神经外科术后谵妄危险因素 Meta分析

Chemical vapor deposition synthesis of two-dimensional freestanding transition metal oxychloride for electronic applications

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Science China(Information Sciences) 2019年第12期62卷 149-163页

作者： shengnan yan Pengfei WANG Chen-Yu WANG Tao XU Zhuan LI Tianjun CAO Moyu CHEN Chen PAN Bin CHENG Litao SUN Shi-Jun LIANG Feng MIAO National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced Microstructures Nanjing University Key Laboratory of MEMS of Ministry of Education Southeast University

Two-dimensional transition metal oxychlorides(MOCl, M = Fe, Cr, V, Ti, Sc) with the metaloxygen plane sandwiched by two layers of chloride ions possess many exotic physical properties. Nevertheless,it is of great challenge to grow two-dimensional single-crystal MOCl because polyvalent nature of transition metal elements usually gives rise to mixed oxyhalides compounds with distinct physical properties. Here, we take VOCl as an example to present a solution for synthesizing 2 D freestanding MOCl with various thicknesses through chemical vapor deposition(CVD) method. The single crystal and elementary composition as well as elements ratio of as-grown samples have been characterized through measurements of X-ray diffraction, X-ray photoelectron spectroscopy and energy-dispersive spectroscopy, respectively. Furthermore, we demonstrate that 2 D VOCl-based memristive devices show low power consumption and excellent device reliability due to the layered-structure and electrically insulating properties of 2 D VOCl flakes. Besides, we utilize the feature of multilevel resistive switching that memristive devices exhibit to emulate depression and potentiation of synaptic plasticity. This method developed in this study may open up a new avenue for the growth of 2 D MOCl with single crystal and pave the way for high-performance electronic applications.

关键词： transition metal oxychlorides chemical vapor deposition freestanding memristive device neuromorphic computing

The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model

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Food Science and Human Wellness 2024年第2期13卷 748-764页

作者： Ruonan yan Chi-Tang Ho yanan Liu shengnan Zhan Zufang Wu Xin Zhang Department of Food Science and Engineering Ningbo UniversityNingbo 315211China Department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08901USA

The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state imbalance.After fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic cells.Our results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health.

关键词： Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism

Development of a multi-component drug from turmeric using central composite design

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Frontiers of Chemical Science and Engineering 2014年第3期8卷 362-368页

作者： Xiaohang ZHANG shengnan HAN yan LI Jianlan JIANG Key Laboratory of Systems Bioengineering Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

A methodology drugs based on traditional to develop multi-component Chinese medicines has been developed using central composite design. Several active components from the traditional Chinese medicine turmeric were chosen for use in a multi-component antitumor drug. Response surface methodology based on a central composite design was applied to determine the quantitative composition-activity relationships in order to optimize the amount of each component in the drug. An MTT （3-（4,5- dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide） assay was used to measure the pharmacological activity as the response value. The experimental antitumor activity of the optimum combination was 92.85% in the MTT assay and superior to the activities of each single component. These results demonstrate that response surface methodology based on a central composite design is suitable for the design of multi-component drugs.

关键词： multi-component drug development centralcomposite design turmeric curcuminoids