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Cyclin D1在黄芪甲苷诱导BMSCs向神经元样细胞分化中的表达

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神经药理学报 2024年第1期14卷 11-17页

作者：王晓寅王会芳罗强张辉张晓丽河北北方学院附属第二医院张家口075000 河北北方学院生命科学研究中心张家口075000

目的:研究黄芪甲苷诱导骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)分化的特点和诱导过程中Cyclin D1的表达特点。方法:采用100 mg·L^(-1)黄芪甲苷诱导BMSCs分化,在1、12、24 h倒置显微镜观察细胞形态变化,免疫细胞... 详细信息

目的:研究黄芪甲苷诱导骨髓间充质干细胞(bone marrow mesenchymal stem cells,BMSCs)分化的特点和诱导过程中Cyclin D1的表达特点。方法:采用100 mg·L^(-1)黄芪甲苷诱导BMSCs分化,在1、12、24 h倒置显微镜观察细胞形态变化,免疫细胞化学方法观察巢蛋白(Nestin)、神经元特异性烯醇化酶(neuron specific enolase,NSE)、Cyclin D1的表达,RT-PCR检测Cyclin D1 mRNA的表达。结果:收集获得的骨髓细胞采用原代和传代培养,至第3代BMSCs细胞基本纯化。经100 mg·L^(-1)黄芪甲苷作用后,部分细胞自胞体长出突起,形态似神经元样细胞且表达Nestin和NSE抗体,Nestin的表达时相早于NSE且表达强度高于NSE(P0.05)。结论:黄芪甲苷可能首先通过调整细胞周期,延长了G1期向S期转变的时间,从而启动了BMSCs的分化程序,诱导BMSCs向神经干细胞分化。在黄芪甲苷的营养作用下,细胞的突起进一步生长并向神经元分化。

关键词：黄芪甲苷 BMSCs 分化神经元样细胞 Cyclin D1

Ng-Perron单位根检验在径流序列非平稳性分析中的应用

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中国农村水利水电 2024年第8期 105-111,119页

作者：王慧方赵雪花郭秋岑武茜茜任智晶太原理工大学水利科学与工程学院山西太原030024

在全球气候变化和高强度人类活动的共同影响下,许多流域天然水循环过程受到破坏。径流序列呈现明显的非平稳特性,给水资源规划、管理、预测和调控带来一定的挑战。揭示径流序列的非平稳特性可以有效应对全球气候变化下的复杂水问题,对... 详细信息

在全球气候变化和高强度人类活动的共同影响下,许多流域天然水循环过程受到破坏。径流序列呈现明显的非平稳特性,给水资源规划、管理、预测和调控带来一定的挑战。揭示径流序列的非平稳特性可以有效应对全球气候变化下的复杂水问题,对降低水文分析难度和提高径流预测精度具有十分重要的意义。研究以汾河上游兰村站为研究对象,分析该站1958-2016年年径流和月径流序列是否平稳。首先从随机水文学角度,采用Mann-Kendall检验法和小波分析法识别径流序列的趋势、突变和周期特征。在此基础上,从统计水文学角度引入Ng-Perron单位根检验方法。通过Mann-Kendall趋势检验和散点图法选择合适的检验方程,对径流序列进行广义最小二乘法(Generalized Least Squares,GLS)退势,并利用修正的信息准则(Modified information criterion,MIC)计算最优时间滞后阶数,判别径流序列是否具有非平稳性。结果显示,径流序列存在趋势、突变和周期成分,为非平稳径流序列。同时Ng-Perron单位根检验表明,该站年、月径流序列在1%显著性水平上具有非平稳特性。相较传统单位根检验方法,Ng-Perron单位根检验采用更为稳健的修正检验统计量,显著调整小样本情况下水平扭曲的现象,具有更好检验水平和功效,因而可以得到更合理的检验结果。研究成果为径流序列非平稳性检验理论的进一步改进及径流预测模型发展与应用提供参考。

关键词：非平稳 Ng-Perron单位根检验径流序列修正的信息准则

维普期刊数据库博看期刊

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不同烤烟品种在咸阳旬邑烟区的适宜性评价

安徽农业科学 2024年第17期52卷 30-33,54页

作者：王慧芳张希王智慧袁华恩来苗赵铭钦郭创江杨照咸阳市烟草公司旬邑分公司陕西咸阳711300 陕西中烟工业有限责任公司技术中心陕西西安710065 安康市烟草公司陕西安康711600 河南农业大学烟草学院河南郑州450046

为筛选出适宜旬邑烟区生态环境的烤烟新品种,为其优质烟叶生产和利用提供依据,于2022年以旬邑烟区主栽品种秦烟99为对照,采用大田试验方法,研究秦烟99、秦烟96、秦烟201、中烟100、豫烟13和Y2001这6个品种的大田生育期、植物学性状、农... 详细信息

为筛选出适宜旬邑烟区生态环境的烤烟新品种,为其优质烟叶生产和利用提供依据,于2022年以旬邑烟区主栽品种秦烟99为对照,采用大田试验方法,研究秦烟99、秦烟96、秦烟201、中烟100、豫烟13和Y2001这6个品种的大田生育期、植物学性状、农艺性状、田间自然发病率、经济性状、常规化学成分含量、烤后烟外观质量和感官质量的差异。结果表明,不同烤烟品种的生育期差异较小,为142~155 d;秦烟96和Y2001田间生长势强,抗病性强,产量、产值和中上等烟比例较高,外观质量和感官质量表现优异,化学成分协调性好,可作为旬邑烟区储备品种进行推广种植。

关键词：烤烟品种咸阳旬邑烟区产质量适宜性评价

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Structure and 2p decay mechanism of^(18)Mg

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Nuclear Science and Techniques 2024年第6期35卷 145-154页

作者： Long Zhou De-Qing fang Si-Min wang hui Hua Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China

The recently discovered,extremely proton-rich nuclide 18 Mg exhibits ground-state decay via two sequential two-proton(2p)emissions through the intermediate nucleus,*** study investigates the structure and the initial 2p decay mechanism of^(18)Mgby examining the density and correlations of the valence protons using a three-body Gamow coupled-channel *** results show that the ground state of^(18)Mgis significantly influenced by the continuum,resulting in a significant s-wave ***,based on the current framework,this does not lead to a significant deviation in mirror symmetry in either the structure or spectroscopy of the 18Mg-18C ***,the time evolution analysis of the^(18)Mgground state suggests a simultaneous 2p emission during the first step of *** observed nucleon-nucleon correlations align with those of the light-mass 2p emitters,indicating a consistent decay behavior within this nuclear region.

关键词： Structure of^(18)Mg Two-proton decay Proton-proton correlation

Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure

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China Ocean Engineering 2024年第1期38卷 1-17页

作者： DING Xiao-de ZHANG Jian wang fang JIAO hui-feng wang Ming-lu School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Engineering Research Center of Marine Renewable Energy College of Engineering Science and Technol-ogyShanghai Ocean UniversityShanghai 201306China China Ship Scientific Research Center Wuxi 214082China

The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater ***,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape *** critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s *** numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were *** results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical *** formula can be extended to estimate the buckling capacity of water-drop-shaped pressure *** addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping ***,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical *** experimental results were consistent with the numerical *** results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt *** paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories.

关键词： buckling pressure hull water drop underwater observatory

Adhesion property of AlCrNbSiTi high-entropy alloy coating on zirconium:experimental and theoretical studies

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Nuclear Science and Techniques 2024年第8期35卷 79-91页

作者： Bao‑Liang Zhang Wen‑Guan Liu Meng‑He Tu Can fang Yan Liu Yu‑hui wang Yong Hu hui wang China Institute of Atomic Energy Beijing 102413China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

Experimental scratch tests and first-principles calculations were used to investigate the adhesion property of AlCrNbSiTi high-entropy alloy(HEA)coatings on zirconium *** HEA and Cr coatings were deposited on Zr alloy substrates using multi-arc ion plating technology,and scratch tests were subsequently conducted to estimate the adhesion property of the *** results indicated that Cr coatings had better adhesion strength than HEA coatings,and the HEA coatings showed *** special quasi-random structure approach was used to build HEA models,and Cr/Zr and HEA/Zr interface models were employed to investigate the cohesion between the coatings and Zr substrate using first-principles *** calculated interface energies showed that the cohesion between the Cr coating and the Zr substrate was stronger than that of the HEA coating with *** contrary to Al or Si in the HEA coating,Cr,Nb,and Ti atoms binded strongly with Zr *** on the calculated elastic constants,it was found that low Cr and high Al content decreased the mechanical performances of HEA ***,this study demonstrated the utilization of a combined approach involving first-principles calculations and experimental studies for future HEA coating development.

关键词： High-entropy alloy coating Cr coating Adhesion property Scratch test First-principles calculation

Overcoming the Na-ion conductivity bottleneck for the cost-competitive chloride solid electrolytes

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Journal of Energy Chemistry 2024年第8期95卷 1-8,I0001页

作者： Lv Hu hui Li fang Chen Yating Liu Jinzhu wang Cheng Ma Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026AnhuiChina National Synchrotron Radiation Laboratory Hefei 230026AnhuiChina

Chloride solid electrolytes possess multiple advantages for the construction of safe,energy-dense allsolid-state sodium batteries,but presently the chlorides with sufficiently high cost-competitiveness for commercialization almost all exhibit low Na-ion conductivities of around 10^(-5)S cm^(-1)or ***,we report a chloride solid electrolyte,Na_(2.7)ZFCl_(5.3)O_(0.7),which reaches a Na-ion conductivity of 2.29×10^(-4)S cm^(-1)at 25℃without involving overly expensive raw materials such as rare-earth chlorides or Na_(2)*** addition to the efficient ion transport,Na_(2.7)ZrCl_(5.3)O_(0.7)also shows an excellent deformability surpassing that of the widely studied Na_(3)PS_(4),Na_(3)SbS_(4),and Na_(2)ZrCl_(6)solid *** combination of these advantages allows the all-solid-state cell based on Na_(2.7)ZrCl_(5.3)O_(0.7)and NaCrO_(2)to realize stable room-temperature cycling at a much higher specific current than those based on other non-viscoelastic chloride solid electrolytes in literature(120 mA g^(-1)vs.12-55 mA g^(-1));after 100 cycles at such a high rate,the Na_(2.7)ZFCl_(5.3)O_(0.7)-based cell can still deliver a discharge capacity of 80 mAh g^(-1)at25℃.

关键词： All-solid-state sodium batteries Ionic conductivities Solid electrolytes Chlorides High voltage stability

Time-optimal Trajectories for a Car-like Robot

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自动化学报 2008年第4期34卷 445-452页

作者： wang hui-fang CHEN Yang-Zhou College of Electronic Information and Control Engineering Bei-jing University of Technology Beijing 100022 P.R. China

这份报纸为完成时间最佳的轨道的足够的家庭在基于几何最佳的控制理论歧管的 3-dimensional 连接机器人的任何二种配置提供一个新几何方法。我们为分析非线性的问题的这种特殊类型提供一个新观点。从 Pontryagin 的最小的原则(PMP ) 和... 详细信息

这份报纸为完成时间最佳的轨道的足够的家庭在基于几何最佳的控制理论歧管的 3-dimensional 连接机器人的任何二种配置提供一个新几何方法。我们为分析非线性的问题的这种特殊类型提供一个新观点。从 Pontryagin 的最小的原则(PMP ) 和谎言代数学基于切换的功能和他们的衍生物的结构的特征，我们造一个特殊坐标系统并且介绍新向量。我们发现在这新向量的旋转轨道和最佳的控制轨道之间的一对一的印射。而且，我们定义表示位置和这向量的旋转方向的切换的向量，并且得出一个结论规定起始、最后的切换的向量能特别地决定一条最佳的轨道。另外，它是能直接被使用选择一条时间最佳的轨道的一个条件被提供的第一次。

关键词：汽车机器人最优化设计自动化系统

2D–3D dual carbon layer confined ultrasmall VN nanoparticles for improving lithium-ion storage in hybrid capacitors

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Rare Metals 2024年第1期43卷 65-75页

作者： Zhao-Wei Hu hui-fang Li Peng wang Wan-Li wang Lei Yang Xiao-Jun wang Zhi-Ming Liu College of Electromechanical Engineering Shandong Engineering Laboratory for Preparation and Application of High-Performance Carbon-MaterialsQingdao University of Science&TechnologyQingdao 266061China Research Center for Intelligent and Wearable Technology College of Textiles and ClothingQingdao UniversityQingdao 266071China

Lithium-ion capacitors(LICs) of achieving high power and energy density have garnered significant attention. However, the kinetics unbalance between anode and cathode can impede the application of LICs. Vanadium nitride(VN) with a high theoretical specific capacity(~ 1200 m Ah·g^(-1)) is a better pseudocapacitive anode to match the response of cathode in LICs. However, the insertion/extraction of Li-ions in VN's operation results in significant volume expansion. Herein, the VN/N-r GO-5composite that three-dimentional(3D) dicyandiamidederived-carbon(DDC) tightly wrapped VN quantum dots(VN QDTs) on two-dimentional(2D) reduced graphene oxid(r GO) was prepared by a facile strategy. The VN QDTs can reduce ion diffusion length and improve charge transfer kinetics. The 2D r GO as a template provides support for nanoparticle dispersion and improves electrical conductivity. The 3D DDC tightly encapsulated with VN QDTs mitigates agglomeration of VN particles as well as volume expansion. Correspondingly, the LICs with VN/Nr GO-5 composite as anode and activated carbon(AC) as cathode were fabricated, which exhibits a high energy density and power density. Such strategy provides a perspective for improving the electrochemical properties of LIC anode materials by suppressing volume expansion and enhancing conductivity.

关键词： Vanadium nitride(VN)quantum dots Reduced graphene oxide(rGO)nanosheets Dicyandiamide-derived-carbon 2D–3D dual carbon layer Lithium-ion capacitors