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3D printing of poly(ethyleneimine)-functionalized Mg-Al mixed metal oxide monoliths for direct air capture of CO_(2)
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作者 Qingyang Shao Zhuozhen Gan +4 位作者 Bingyao Ge Xuyi Liu Chunping Chen Dermot O’Hare Xuancan Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期491-500,共10页
Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from t... Direct air capture(DAC)of CO_(2)plays an indispensable role in achieving carbon-neutral goals as one of the key negative emission technologies.Since large air flows are required to capture the ultradilute CO_(2)from the air,lab-synthesized adsorbents in powder form may cause unacceptable gas pressure drops and poor heat and mass transfer efficiencies.A structured adsorbent is essential for the implementation of gas-solid contactors for cost-and energy-efficient DAC systems.In this study,efficient adsorbent poly(ethyleneimine)(PEI)-functionalized Mg-Al-CO_(3)layered double hydroxide(LDH)-derived mixed metal oxides(MMOs)are three-dimensional(3D)printed into monoliths for the first time with more than 90%adsorbent loadings.The printing process has been optimized by initially printing the LDH powder into monoliths followed by calcination into MMO monoliths.This structure exhibits a 32.7%higher specific surface area and a 46.1%higher pore volume,as compared to the direct printing of the MMO powder into a monolith.After impregnation of PEI,the monolith demonstrates a large adsorption capacity(1.82 mmol/g)and fast kinetics(0.7 mmol/g/h)using a CO_(2)feed gas at 400 ppm at 25℃,one of the highest values among the shaped DAC adsorbents.Smearing of the amino-polymers during the post-printing process affects the diffusion of CO_(2),resulting in slower adsorption kinetics of pre-impregnation monoliths compared to post-impregnation monoliths.The optimal PEI/MeOH ratio for the post-impregnation solution prevents pores clogging that would affect both adsorption capacity and kinetics. 展开更多
关键词 3d printing Mixed metal oxides Amine functionalization Structured adsorbent direct air capture
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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong Ding Wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3d pose reconstruction assessment of movement function plane of features of human motion
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Electrostatic Attraction and Repulsion Explained and Modelled Mathematically Using Classical Physics—A Detailed Mechanism Based on Particle Wave Functions
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1050-1062,共13页
The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has... The phenomenon of electrical attraction and repulsion between charged particles is well known, and described mathematically by Coulomb’s Law, yet until now there has been no explanation for why this occurs. There has been no mechanistic explanation that reveals what causes the charged particles to accelerate, either towards or away from each other. This paper gives a detailed explanation of the phenomena of electrical attraction and repulsion based on my previous work that determined the exact wave-function solutions for both the Electron and the Positron. It is revealed that the effects are caused by wave interactions between the wave functions that result in Electromagnetic reflections of parts of the particle’s wave functions, causing a change in their momenta. 展开更多
关键词 ELECTrOSTATIC Electron POSITrON COULOMB Force ATTrACTION rEPULSION Wave function Electric Magnetic radiation Pressure Shell THEOrEM 3d Computer Model Quantum
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTrON POSITrON Wave function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3d Model Schrödinger Equation rMS KLEIN GOrdON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field density Phase Flow Attraction rEPULSION Shell Theorem Ehrenfest VIrIAL Normalization Harmonic Oscillator
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2型糖尿病患者维生素D水平与血清CRP、自身免疫抗体及甲状腺功能的相关性
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作者 姚莉敏 付士玲 郎少磊 《河南医学研究》 CAS 2024年第16期2988-2992,共5页
目的研究2型糖尿病患者维生素D水平与血清C反应蛋白(CRP)、自身免疫抗体及甲状腺功能的相关性。方法选取2018年1月至2019年1月于信阳职业技术学院附属医院就诊的150例2型糖尿病患者为研究组,同期选取50例健康体检者作为对照组。检测血清... 目的研究2型糖尿病患者维生素D水平与血清C反应蛋白(CRP)、自身免疫抗体及甲状腺功能的相关性。方法选取2018年1月至2019年1月于信阳职业技术学院附属医院就诊的150例2型糖尿病患者为研究组,同期选取50例健康体检者作为对照组。检测血清CRP、血清25-羟维生素D[25(OH)D]、胰岛自身免疫抗体和甲状腺功能指标水平并比较两组差异;按血清25(OH)D水平将研究组分为正常组(34例)、不足组(37例)、缺乏组(39例)和严重缺乏组(40例)4个亚组,比较组间血清CRP、胰岛自身免疫抗体阳性率和甲状腺功能指标水平差异;对血清25(OH)D与CRP、胰岛自身免疫抗体阳性率及甲状腺功能指标水平的相关性进行Pearson和Spearman相关性分析;随访3 a,统计甲状腺功能障碍发生率,并绘制受试者工作特征(ROC)曲线分析2型糖尿病患者血清25(OH)D对甲状腺功能障碍的预测效能。结果与对照组比较,研究组血清25(OH)D、TSH水平较低,CRP水平和胰岛自身免疫抗体阳性率较高(P<0.05)。正常组、不足组、缺乏组和严重缺乏组的血清CRP、胰岛自身免疫抗体阳性率和TSH水平比较差异有统计学意义,其中血清CRP、TSH水平逐渐上升(P<0.05)。2型糖尿病患者血清25(OH)D水平与CRP(r=-0.714)、胰岛自身免疫抗体阳性率(r=-0.397)和TSH(r=-0.410)水平均呈负相关(P<0.001)。2型糖尿病患者甲状腺功能障碍发生率为25.33%(38/150),绘制ROC曲线分析血清25(OH)D预测甲状腺功能障碍发生的AUC为0.916。结论2型糖尿病患者血清维生素D与CRP、自身免疫抗体阳性率以及甲状腺功能指标水平存在负相关关系,且对甲状腺功能障碍的发生有一定预测价值。 展开更多
关键词 2型糖尿病 C反应蛋白 维生素d 自身免疫抗体 甲状腺功能
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维生素D不足的老年糖尿病患者胼胝体的MRI影像改变与其认知功能的关系研究
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作者 董俊杰 张玲 马丽 《脑与神经疾病杂志》 CAS 2024年第6期350-354,共5页
目的 研究维生素D摄入不足的老年2型糖尿病(T2DM)患者胼胝体的磁共振(MRI)影像改变与其认知功能的关系。方法 选择新疆维吾尔自治区人民医院干部保健中心一病区收治的127例维生素D摄入不足的老年T2DM患者为研究对象,均进行胼胝体MRI检查... 目的 研究维生素D摄入不足的老年2型糖尿病(T2DM)患者胼胝体的磁共振(MRI)影像改变与其认知功能的关系。方法 选择新疆维吾尔自治区人民医院干部保健中心一病区收治的127例维生素D摄入不足的老年T2DM患者为研究对象,均进行胼胝体MRI检查,并采用蒙特利尔认知评估量表(MoCA)评估其认知功能,根据MoCA评分结果将患者分为认知功能正常组与认知障碍组,对比两组胼胝体的MRI影像表现,探讨患者胼胝体的MRI影像改变与其认知功能的关系。结果 127例维生素D不足的老年T2DM患者中,MoCA评分≥26分者89例(认知功能正常组),MoCA评分<26分者38例(认知功能障碍组)。认知功能障碍组空腹血糖(FBG)、糖化血红蛋白(HbAlc)水平均高于认知功能正常组(P<0.05),维生素D水平低于认知功能正常组(P <0.05)。认知功能障碍组胼胝体压部与胼胝体膝部N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、NAA/肌酸(Cr)、Cho/Cr均低于认知功能正常组(P<0.05),Cr与认知功能正常组比较差异无统计学意义(P> 0.05)。认知功能障碍组胼胝体压部与胼胝体膝部FA值均低于认知功能正常组(P<0.05),表现砚散系数(ADC)值均高于认知功能正常组(P<0.05)。Pearson相关性分析显示,认知功能障碍组胼胝体压部NAA、NAA/Cr与患者MoCA评分均呈正相关(P<0.05),胼胝体膝部NAA、Cho、NAA/Cr、Cho/Cr与患者MoCA评分均表现为正相关性(P<0.05)。认知功能障碍组胼胝体压部、胼胝体膝部FA值与患者MoCA评分均表现为正相关性(P<0.05),胼胝体压部、胼胝体膝部ADC值与患者MoCA评分均呈负相关(P <0.05)。结论 维生素D摄入不足的老年T2DM患者MRI影像改变与其认知功能存在明显相关性,1H-MRS和DTI参数有利于评估维生素D不足的老年T2DM患者认知功能损害情况。 展开更多
关键词 2型糖尿病 老年 维生素d摄入不足 胼胝体MrI 认知功能
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云南省R&D经费投入结构动态研究 被引量:1
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作者 张和平 钟翔 +1 位作者 段江涛 贺新华 《中国科技资源导刊》 2024年第1期92-99,共8页
为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。... 为研究云南省“十二五”以来R&D经费投入结构变化,分析R&D经费投入现状,并与全国,东、中、西部地区及临近省份进行了对比;从资金来源和资金配置视角,运用Cobb-Douglas效用函数及其修正模型对R&D经费投入结构展开动态分析。结果表明:云南省R&D经费投入结构不尽合理,资金来源中政府资金占比较低且呈下降趋势,资金配置中基础研究和应用研究投入不足,与最优结构偏离程度较大。针对存在的问题,提出持续加大政府R&D经费投入力度、围绕产业链提升基础研究和应用研究比重的建议。 展开更多
关键词 r&d经费 政府r&d投入 资源配置 活动类型 云南省 Cobb-douglas效用函数
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政府R&D资助对OFDI逆向绿色创新的影响机制研究 被引量:1
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作者 韩先锋 刘娟 李勃昕 《运筹与管理》 CSCD 北大核心 2024年第1期158-164,共7页
应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会... 应用中国分省区层面数据并采用面板门槛模型,实证考察了政府R&D资助影响OFDI逆向绿色创新的动态效应。研究发现,OFDI对国内绿色创新产生了显著的驱动效应,但这种影响呈现出明显的先负后正的“U”型动态演化特征;政府R&D资助会正向调节OFDI逆向绿色创新溢出,且存在最适宜于OFDI逆向绿色创新的政府R&D资助区间(0.366,0.428],过高或过低强度的政府R&D资助均会在一定程度上造成OFDI逆向绿色创新的红利损失;政府R&D资助调节下OFDI对绿色创新的动态影响具有显著时空异质性,即在时空维度上存在“激励效应”与“挤出效应”交替演化的鲜明特征。 展开更多
关键词 政府r&d资助 对外直接投资 绿色创新
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A methodology for damage evaluation of underground tunnels subjected to static loading using numerical modeling 被引量:1
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作者 Shahriyar Heidarzadeh Ali Saeidi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1993-2005,共13页
We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensiti... We have proposed a methodology to assess the robustness of underground tunnels against potential failure.This involves developing vulnerability functions for various qualities of rock mass and static loading intensities.To account for these variations,we utilized a Monte Carlo Simulation(MCS)technique coupled with the finite difference code FLAC^(3D),to conduct two thousand seven hundred numerical simulations of a horseshoe tunnel located within a rock mass with different geological strength index system(GSIs)and subjected to different states of static loading.To quantify the severity of damage within the rock mass,we selected one stress-based(brittle shear ratio(BSR))and one strain-based failure criterion(plastic damage index(PDI)).Based on these criteria,we then developed fragility curves.Additionally,we used mathematical approximation techniques to produce vulnerability functions that relate the probabilities of various damage states to loading intensities for different quality classes of blocky rock mass.The results indicated that the fragility curves we obtained could accurately depict the evolution of the inner and outer shell damage around the tunnel.Therefore,we have provided engineers with a tool that can predict levels of damages associated with different failure mechanisms based on variations in rock mass quality and in situ stress state.Our method is a numerically developed,multi-variate approach that can aid engineers in making informed decisions about the robustness of underground tunnels. 展开更多
关键词 Fragility curves Underground tunnels Vulnerability functions Brittle damage FLAC3d Numerical modeling
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R&D资本化背景下我国TFP增长率再测算
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作者 杜瑶 许永洪 《统计研究》 北大核心 2024年第1期33-45,共13页
研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前... 研究与试验发展(R&D)资本对经济增长和科技创新作用日益凸显,但对于R&D资本的核算亟待完善。本文基于SNA2008和CSNA2016框架,将R&D支出作为资本形成,对我国各省份物质资本存量和R&D资本存量进行规范化测算,使用随机前沿分析法重新估算1991—2019年间的全要素生产率(TFP)增长率。研究发现:第一,我国R&D资本存量规模呈总体递增和地区聚集趋势;第二,1991—2019年间,我国广义TFP增长率年平均增幅为2.10%,对经济增长存在正向作用;第三,将TFP增长率分解为技术进步、前沿技术效率和规模效应,发现技术进步对TFP增长率的贡献最大,是推动我国TFP增长的主导力量,但却呈现逐年递减的趋势;第四,随着我国对R&D投入的不断增加与重视,R&D对我国广义TFP增长率的贡献呈现递增的趋势,R&D的贡献逐渐成为推动我国科技进步的主要力量。 展开更多
关键词 r&d资本化 r&d资本存量 TFP增长率 随机前沿分析
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Databases of 2D material-substrate interfaces and 2D charged building blocks
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作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2d material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
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An adaptive physics-informed deep learning method for pore pressure prediction using seismic data
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作者 Xin Zhang Yun-Hu Lu +2 位作者 Yan Jin Mian Chen Bo Zhou 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期885-902,共18页
Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the g... Accurate prediction of formation pore pressure is essential to predict fluid flow and manage hydrocarbon production in petroleum engineering.Recent deep learning technique has been receiving more interest due to the great potential to deal with pore pressure prediction.However,most of the traditional deep learning models are less efficient to address generalization problems.To fill this technical gap,in this work,we developed a new adaptive physics-informed deep learning model with high generalization capability to predict pore pressure values directly from seismic data.Specifically,the new model,named CGP-NN,consists of a novel parametric features extraction approach(1DCPP),a stacked multilayer gated recurrent model(multilayer GRU),and an adaptive physics-informed loss function.Through machine training,the developed model can automatically select the optimal physical model to constrain the results for each pore pressure prediction.The CGP-NN model has the best generalization when the physicsrelated metricλ=0.5.A hybrid approach combining Eaton and Bowers methods is also proposed to build machine-learnable labels for solving the problem of few labels.To validate the developed model and methodology,a case study on a complex reservoir in Tarim Basin was further performed to demonstrate the high accuracy on the pore pressure prediction of new wells along with the strong generalization ability.The adaptive physics-informed deep learning approach presented here has potential application in the prediction of pore pressures coupled with multiple genesis mechanisms using seismic data. 展开更多
关键词 Pore pressure prediction Seismic data 1d convolution pyramid pooling Adaptive physics-informed loss function High generalization capability
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Ultrathin poly(cyclocarbonate-ether)-based composite electrolyte reinforced with high-strength functional skeleton 被引量:1
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作者 Xiaojiao Zheng Da Xu +1 位作者 Ning Fu Zhenglong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期603-612,I0013,共11页
Composite polymer electrolytes(CPEs)are considered to be the most promising to break through the performance and safety limitations of traditional lithium-ion batteries because of their excellent electrochemical and m... Composite polymer electrolytes(CPEs)are considered to be the most promising to break through the performance and safety limitations of traditional lithium-ion batteries because of their excellent electrochemical and mechanical properties.Aiming at the performance limitations of the most common polyether matrix such as poly(ethylene oxide)(PEO),a novel poly(cyclocarbonate-ether)polymer matrix was prepared by in-situ thermal curing,the weaker interaction between its C=O bond and Li^(+)can promote the rapid transport of Li^(+).Adding ionic liquid and active filler LLZTO to the matrix can synergistically reduce the crystallinity of matrix and promote the dissociation of lithium salts.In addition,a 3D functional skeleton made of polyacrylonitrile(PAN)and lithium fluoride(LiF)can greatly improve the mechanical strength of polymer matrix after cold pressing,and Li F is also conducive to interface stability.The thickness of the optimal sample(VP6L/CPL)was only 25μm,and its ionic conductivity,lithium ion transference number,and electrochemical stability window were as high as 7.17×10^(-4)S cm^(-1)(25℃),0.54 and 5.4 V,respectively,while the mechanical strength reaches 6.1 MPa,which can fully inhibit the growth of lithium dendrites.The excellent electrochemical performance and mechanical strength enable the assembled Li|VP6L/CPL|Li battery to be continuously charged for over 200 h and cycled stably for more than 2300 h,and Li|VP6L/CPL|LFP battery can be stably cycled for more than 400 and 550 cycles at 1 C(40℃)and 0.5 C(25℃),respectively. 展开更多
关键词 Composite polymer electrolytes Polymer matrix 3d functional skeleton PLASTICIZATION Synergistic effect
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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine d3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUrOMOdULATION Parkinson’s disease primary motor cortex
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Petrographic, Geochemical and Metallogenical Context of the Geological Formations of the Goumere Region (North-East of Cote D’Ivoire): Implication to the Knowledge of Gold Mineralization
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作者 Fossou Jean-Luc Hervé Kouadio Alain Nicaise Kouamelan +1 位作者 Topka Kakeu Lionel Boya Roger Nicaise Kanga 《International Journal of Geosciences》 CAS 2024年第2期180-203,共24页
The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for stu... The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for studies using petrographic, geochemical and metallogenic methods. The study of macroscopic and microscopic petrography made it possible to highlight two major lithological units: 1) a volcano-plutonic unit, formed of gabbros, basalt, volcaniclastics and rhyodacite;2) a sedimentary unit (microconglomerate). From a geochemical point of view, the results obtained indicate that the plutonites are gabbro and gabbro diorite while the volcanics have compositions of basaltic andesites, rhyolite and dacites. The sediments have a litharenitic to sublitharenitic character. The metallogenic study made it possible to highlight hydrothermal alterations and metalliferous paragenesis on the formations studied. Hydrothermal alteration is characterized by the presence of carbonation, silicification, sericitization, sulfidation and to a lesser degree chloritization. Metalliferous paragenesis consists of pyrite, chalcopyrite, hematite and magnetite. 展开更多
关键词 PETrOGrAPHY GEOCHEMISTrY METALLOGENY Gouméré Côte d’Ivoire
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政府采购对企业R&D投入的影响
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作者 张士博 赵雪键 +1 位作者 岳松森 李连伟 《山东工商学院学报》 2024年第1期46-56,107,共12页
针对政府采购对企业R&D投入激励的有效性问题,基于2011—2013年中国上市中小企业政府采购数据,采用倾向得分匹配法,研究政府采购、公司内部治理与企业R&D投入之间的关系。研究结果表明,政府采购能够有效促进企业R&D投入,且... 针对政府采购对企业R&D投入激励的有效性问题,基于2011—2013年中国上市中小企业政府采购数据,采用倾向得分匹配法,研究政府采购、公司内部治理与企业R&D投入之间的关系。研究结果表明,政府采购能够有效促进企业R&D投入,且这种影响因公司治理结构的不同而表现出明显的差异;政府采购对国有性质、股权分散、股权制衡及董事会规模较小的企业R&D投入的促进效应更加显著。 展开更多
关键词 政府采购 r&d投入 公司内部治理 倾向得分匹配法
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基于Tobit模型的河南省R&D投入产出影响因素分析
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作者 王新 《河南科技》 2024年第10期144-148,共5页
【目的】科技创新能力是地区综合实力的重要标志之一,科学地识别影响科技资源投入产出的因素,是实现经济跨越式发展和可持续发展的关键。【方法】基于Tobit模型对近十年河南省R&D投入产出面板数据进行相关检验,分析得出各变量对河南... 【目的】科技创新能力是地区综合实力的重要标志之一,科学地识别影响科技资源投入产出的因素,是实现经济跨越式发展和可持续发展的关键。【方法】基于Tobit模型对近十年河南省R&D投入产出面板数据进行相关检验,分析得出各变量对河南省R&D投入产出产生的不同影响。【结果】企业研发机构投入和高水平人才比例与河南省R&D投入产出效率呈显著正相关,而政府支持力度和对外开放程度则对R&D投入产出效率的作用不显著。【结论】建议河南省通过转换政府职能、注重人才引进、加强对外交流、改善区域环境等方式,优化R&D投入产出,更好地提升科技效能。 展开更多
关键词 r&d 影响因素 TOBIT模型
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Comparison of R and Excel in the Field of Data Analysis
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作者 Jue Wang 《Journal of Electronic Research and Application》 2024年第3期178-184,共7页
This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and i... This research paper compares Excel and R language for data analysis and concludes that R language is more suitable for complex data analysis tasks.R language’s open-source nature makes it accessible to everyone,and its powerful data management and analysis tools make it suitable for handling complex data analysis tasks.It is also highly customizable,allowing users to create custom functions and packages to meet their specific needs.Additionally,R language provides high reproducibility,making it easy to replicate and verify research results,and it has excellent collaboration capabilities,enabling multiple users to work on the same project simultaneously.These advantages make R language a more suitable choice for complex data analysis tasks,particularly in scientific research and business applications.The findings of this study will help people understand that R is not just a language that can handle more data than Excel and demonstrate that r is essential to the field of data analysis.At the same time,it will also help users and organizations make informed decisions regarding their data analysis needs and software preferences. 展开更多
关键词 EXCEL r language data analysis Open source COMPArE data management Advantages disadvantages function
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R&D投入对企业绩效影响的统计研究
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作者 蓝志清 汪洋 《河南科技》 2024年第3期154-157,共4页
【目的】对R&D投入与企业绩效的影响关系进行统计研究,为江西省上市公司进行R&D投入合理规划、提升企业绩效和促进创新驱动发展提供建议。【方法】基于江西省2019—2021年上市公司的面板数据,构建面板门槛回归模型,分析了R&... 【目的】对R&D投入与企业绩效的影响关系进行统计研究,为江西省上市公司进行R&D投入合理规划、提升企业绩效和促进创新驱动发展提供建议。【方法】基于江西省2019—2021年上市公司的面板数据,构建面板门槛回归模型,分析了R&D投入对企业绩效的门槛效应。【结果】单一门槛、双重门槛、三重门槛均通过了显著性检验,在不同门槛值区间时,R&D投入对企业绩效的边际系数符号及其显著性存在明显差异。【结论】企业应根据自身所处的R&D投入区间合理制定相应的研发计划,当企业R&D投入处于低区间时,应当加大R&D投入;当R&D投入上升至一定区间时,则需重点关注R&D投入效率问题,以避免R&D投入对企业绩效的抑制作用。 展开更多
关键词 r&d投入 企业绩效 面板门槛回归模型
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An Analysis of Liberia’s Vulnerability to Climate Change in the Context of Least Developed Countries (LDCs): A Review
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作者 Charles Flomo Togbah 《American Journal of Climate Change》 2024年第2期230-250,共21页
Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation c... Climate change is an alarming global challenge, particularly affecting the least developed countries (LDCs) including Liberia. These countries, located in regions prone to unpredictable temperature and precipitation changes, are facing significant challenges, particularly in climate-sensitive sectors such as mining and agriculture. LDCs need more resilience to adverse climate shocks but have limited capacity for adaptation compared to other developed and developing nations. This paper examines Liberia’s susceptibility to climate change as a least developed country, focusing on its exposure, sensitivity, and adaptive capacity. It provides an overview of LDCs and outlines the global distribution of carbon dioxide emissions. The paper also evaluates specific challenges that amplify Liberia’s vulnerability and constrain sustainable adaptation, providing insight into climate change’s existing and potential effects. The paper emphasizes the urgency of addressing climate impacts on Liberia and calls for concerted local and international efforts for effective and sustainable mitigation efforts. It provides recommendations for policy decisions and calls for further research on climate change mitigation and adaptation. 展开更多
关键词 Least developed Countries LIBErIA Climate Change VULNErABILITY POVErTY HUNGEr disease research and development (r&d) Adaptation
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