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Numerical simulation of gap effect in supersonic flows 被引量:1
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作者 Song Mo Haiming Huang +2 位作者 Guo Huang Xiaoliang Xu Zimao Zhang 《Theoretical & Applied Mechanics Letters》 CAS 2014年第4期65-69,共5页
The gap effect is a key factor in the design of the heat sealing in super- sonic vehicles subjected to an aerodynamic heat load. Built on S-A turbulence model and Roe discrete format, the aerodynamic environment aroun... The gap effect is a key factor in the design of the heat sealing in super- sonic vehicles subjected to an aerodynamic heat load. Built on S-A turbulence model and Roe discrete format, the aerodynamic environment around a gap on the surface of a supersonic aircraft was simulated by the finite volume method. As the presented results indicate, the gap effect depends not only on the attack angle, but also on the Mach number. 展开更多
关键词 gap effect supersonic flow numerical simulation thermal protection
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Influence of social capital on farmer household income gap:total effect and structural effect 被引量:1
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作者 Geling Wang Qian Lu 《Chinese Journal of Population,Resources and Environment》 2016年第1期30-37,共8页
Based on the survey data of typical villages in Shaanxi Province,China,the effect of social capital on the income gap of farmers' households was analyzed using the Shapley value of the total amount of social capit... Based on the survey data of typical villages in Shaanxi Province,China,the effect of social capital on the income gap of farmers' households was analyzed using the Shapley value of the total amount of social capital and the social capital structure.The results show the following:first,social capital can expand the household income gap,and the effect of this index on the household income gap is 7.54%.Second,the indexes of the social capital dimension can expand the household income gap,and the structural effects of the household income gap on social networks,social trust,and social participation are 3.17%,3.64%,and 0.65%,respectively.Third,no dimension of the path is the same as the effect on the household income gap. 展开更多
关键词 Income gap social capital structural effect total effect
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Pharmacological Effects of Statins Related to Gap Junction Modulation 被引量:1
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作者 Lili Qu Jiandong Jiang Weijia Kong 《Pharmacology & Pharmacy》 2014年第4期319-331,共13页
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, or “statins”, are widely using cholesterol-lowering drugs with pleiotropic pharmacological effects. In this review, we summarized the pharmacolog... 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, or “statins”, are widely using cholesterol-lowering drugs with pleiotropic pharmacological effects. In this review, we summarized the pharmacological effects of statins related to gap junction modulation. The main function of cellular gap junctions, which are composed of trans-membrane proteins named connexins (Cxs), is to mediate direct cell-to-cell communication through material exchange. Statins could rectify the disturbed expression, distribution, or phosphorylation of Cxs and thus modify the functions of gap junctions in a variety of tissues like the aorta, cardiomyocytes, or tumors. The effects of statins on Cxs and gap junctions were associated with their pharmacological activities against atherosclerosis, arrhythmias, and tumors. Despite some evidences suggested that the anti-inflammatory or HMG-CoA reductase inhibiting effects of statins may contribute in part to the modulation of Cxs and gap junctions, the detailed underlying mechanisms are largely unrevealed and merit further investigation. In addition, it is likely that the modulating effects of statins on gap junctions may also contribute to their pharmacological activities against some diabetic complications. Future studies of these issues will help to provide scientific evidences for the appropriate clinical application of statins. 展开更多
关键词 STATIN CONNEXIN gap JUNCTION ATHEROSCLEROSIS ARRHYTHMIA BYSTANDER effect
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Tunable Band Gap in Piezoelectric Composite Rod Based on the Inter-Coupling Effect
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作者 Ze-Qun Fang Zhi-Lin Hou 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期60-64,共5页
The longitudinal wave propagating in one-dimensional periodic piezoelectric composite rod with inter-coupling between different piezoelectric segments is investigated. The analytical formulae for such a structure are ... The longitudinal wave propagating in one-dimensional periodic piezoelectric composite rod with inter-coupling between different piezoelectric segments is investigated. The analytical formulae for such a structure are shown and the dispersion relation is calculated. The results show that, by introducing the inter-coupling between the different piezoelectric segments, which is accomplished by serially connecting every n piezoelectric segment into supercells, some tunable Bragg band gaps can accordingly be opened in the low frequency region. The investigation could provide a new guideline for the tunable phononic crystal under passive control. 展开更多
关键词 UUT Tunable Band gap in Piezoelectric Composite Rod Based on the Inter-Coupling effect TP BG TN
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Improved photovoltaic effects in Mn-doped BiFeO3 ferroelectric thin films through band gap engineering
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作者 阎堂柳 陈斌 +7 位作者 刘钢 牛瑞鹏 尚杰 高双 薛武红 金晶 杨九如 李润伟 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期401-405,共5页
As a low-bandgap ferroelectric material, BiFeO3 has gained wide attention for the potential photovoltaic applications,since its photovoltaic effect in visible light range was reported in 2009. In the present work, Bi... As a low-bandgap ferroelectric material, BiFeO3 has gained wide attention for the potential photovoltaic applications,since its photovoltaic effect in visible light range was reported in 2009. In the present work, Bi(Fe, Mn)O3thin films are fabricated by pulsed laser deposition method, and the effects of Mn doping on the microstructure, optical, leakage,ferroelectric and photovoltaic characteristics of Bi(Fe, Mn)O3 thin films are systematically investigated. The x-ray diffraction data indicate that Bi(Fe, Mn)O3 thin films each have a rhombohedrally distorted perovskite structure. From the light absorption results, it follows that the band gap of Bi(Fe, Mn)O3 thin films can be tuned by doping different amounts of Mn content. More importantly, photovoltaic measurement demonstrates that the short-circuit photocurrent density and the open-circuit voltage can both be remarkably improved through doping an appropriate amount of Mn content, leading to the fascinating fact that the maximum power output of ITO/BiFe(0.7)Mn(0.3)O3/Nb-STO capacitor is about 175 times higher than that of ITO/BiFeO3/Nb-STO capacitor. The improvement of photovoltaic response in Bi(Fe, Mn)O3 thin film can be reasonably explained as being due to absorbing more visible light through bandgap engineering and maintaining the ferroelectric property at the same time. 展开更多
关键词 band gap engineering BIFEO3 Mn doping FERROELECTRIC photovoltaic effect
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Study on Stack Effect of Stairwell by Numerical Model of Leakage Flow through Gap of Door
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作者 Jung-Yup Kim Ji-Seok Kim 《Open Journal of Fluid Dynamics》 2013年第4期241-247,共7页
Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an anal... Since stack effect that occurs in high-rise buildings has an effect on the indoor environment of the buildings, energy loss and smoke control in case of a fire, there is a need to conduct research on this. For an analysis of the stack effect, analysis methods on the leakage flow through gap of interior door shall be formulated. Until now, studies related to the gap leakage flow in buildings have mainly analyzed flow field and pressure in the buildings one-dimensionally using pressure difference-leakage flowrate relations of Orifice Equation and a network numerical analysis algorithm that as- sumes each compartment in the buildings as a single point. In this study, the Momentum Loss Model which enables pressure drop to be proportional to the flow velocity through the gap of door in computational domain of 3-dimensional numerical analysis was proposed to reflect the gap flow phenomenon effectively in 3-dimensional numerical analysis. Using the proposed model, 3-dimensional numerical analysis of the stack effect on the stairs in buildings was performed, and the effects of separation door and lobby between stair and accommodation on the stack effect were investigated. 展开更多
关键词 STACK effect LEAKAGE Flow gap of DOOR MOMENTUM Loss Model Separation DOOR NUMERICAL Analysis
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One-dimensional theoretical analysis on charged-particle transports in a decaying plasma with an initial plasma-electrode gap
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作者 Xin-Li Sun Yao-Ting Wang +5 位作者 Lan-Yue Luo Zi-Ming Zhang Meng-Long Zhang He-Ping Li Dong-Jun Jiang Ming-Sheng Zhou 《Chinese Physics B》 2025年第11期447-459,共13页
An analytical model for describing the charged-particle transport in a wall-confined laser-induced decaying plasma is established under an external electrostatic field,focusing on the effects of the initial plasma-ele... An analytical model for describing the charged-particle transport in a wall-confined laser-induced decaying plasma is established under an external electrostatic field,focusing on the effects of the initial plasma-electrode gap(IPEG)that exists in applications such as laser isotope separation.This newly developed analytical model is validated by particle-in-cell simulations and the experimental scaling relation,and can also be reduced to its previously published counterpart that did not consider IPEGs.Based on this analytical model,the influences of different IPEG spacings on the characteristics of the whole ion extraction process are studied.The results show that the ion extraction ratios at the endpoints of the first and second stages both decrease with increasing IPEG spacing,while the corresponding time durations for the first two stages show a non-monotonous variation trend.The specific ion extraction time,defined as the ion extraction time per unit mass to comprehensively characterize the ion extraction efficiency,increases generally with the increase of IPEG spacing.This study not only provides further insight into the fundamental physical processes in a wall-bounded decaying plasma under an externally applied electrostatic field,but also offers useful theoretical guidance for optimal designs of geometrical and operating parameters in laser isotope separation processes. 展开更多
关键词 decaying plasma charged-particle transport effect of plasma-electrode gap theoretical analysis PIC simulation
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Effects of Hydroxyl Radicals on Introduced Organisms of Ship's Ballast Water Based Micro-Gap Discharge 被引量:2
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作者 白敏冬 张芝涛 +2 位作者 白敏菂 杨波 白希尧 《Plasma Science and Technology》 SCIE EI CAS CSCD 2007年第2期206-210,共5页
With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship's ballast water.... With the physical method of micro-gap gas discharge, OH. radicals were produced by the ionization of O2 in air and H2O in the gaseous state, in order to explore more effective method totreat the ship's ballast water. The surface morphology of Al2O3 dielectric layer was analysed using Atomic Force Microscopy (AFM), where the size of Al2O3 particles was in the range of 2 μm to 5 μm. At the same time, the biochemical effect of hydroxyl radicals on the introduced organisms and the quality of ship's ballast water were studied. The results indicate that the main reasons of cell death are lipid peroxide and damage of the antioxidant enzyme system in Catalase (CAT), Peroxidase (POD) and Superoxide dismutase (SOD). In addition, the quality of the ballast water was greatly improved. 展开更多
关键词 micro-gap discharge α-Al2O3 dielectric layers introduced organisms hydroxyl radical biochemistry effect
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城市间技术互补、资本非对称流动与区域差距收敛
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作者 白雪洁 王欣悦 《经济问题探索》 北大核心 2026年第2期136-154,共19页
促进资本自由流动和合理配置是构建全国统一大市场、实现区域协调发展的重要举措。本文利用2011—2022年中国沪深A股上市公司母子公司地理区位信息,从规模和方向两个维度检验城市间技术互补对资本流动的影响及其在缩小区域差距中的作用... 促进资本自由流动和合理配置是构建全国统一大市场、实现区域协调发展的重要举措。本文利用2011—2022年中国沪深A股上市公司母子公司地理区位信息,从规模和方向两个维度检验城市间技术互补对资本流动的影响及其在缩小区域差距中的作用。研究发现,城市间技术互补有利于推动资本跨区域流动,并促使资本更多地从技术互补获益低的城市流向获益高的城市,表现为资本流动的非对称性。机制分析发现,城市间技术互补通过增强异地投资企业的创新能力和促进知识流动提升资本跨区域流动规模,技术互补收益在城市间分配的非均等性会通过提供差异化的政策激励和市场规模扩张效应促进资本非对称流动。拓展分析发现,技术互补有利于增强资本流动的“扩散效应”,显著缩小城市间劳动生产率差异、创新鸿沟和经济发展差距。本文以技术互补为抓手提出破解“卢卡斯悖论”的新路径,为引导资本布局弱势地区、落实区域协调发展战略提供重要的决策启示。 展开更多
关键词 技术互补 资本流动 卢卡斯悖论 扩散效应 区域差距
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益气活血中药对脑出血大鼠GAP-43和Arc的影响 被引量:3
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作者 李艳青 谢荃 《中医临床研究》 2016年第30期77-78,共2页
目的:观察益气活血中药制剂对脑出血大鼠脑组织GAP-43和Arc的影响。方法:用自体血注入法建立大鼠脑出血模型,分空白组、阳性组和实验组。阳性组造模1 d后开始腹腔注射神经节苷脂;实验组造模1 d后用益气活血中药制剂灌胃。分别于干预后1 ... 目的:观察益气活血中药制剂对脑出血大鼠脑组织GAP-43和Arc的影响。方法:用自体血注入法建立大鼠脑出血模型,分空白组、阳性组和实验组。阳性组造模1 d后开始腹腔注射神经节苷脂;实验组造模1 d后用益气活血中药制剂灌胃。分别于干预后1 d、3 d、7 d处死大鼠,用定量PCR法检测各组大鼠脑组织GAP-43和Arc的水平。结果:干预后第7天阳性组与实验组大鼠脑组织GAP-43和Arc含量均高于空白组,差异有统计学意义;第3天实验组GAP-43含量高于阳性组,与阳性组比较差异有统计学意义。结论:益气活血中药制剂对大鼠脑出血损伤后神经结构重建有促进作用,但具体作用机制尚需进一步研究。 展开更多
关键词 中医内科学 益气活血 gap-43 ARC 影响
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多维开放、技术扩散与城乡居民消费差距
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作者 邹洋 徐靖文 《统计与信息论坛》 北大核心 2026年第2期81-96,共16页
在对外开放从“以市场换技术”向“以制度引创新”转型时期,通过深化多维开放带动资源要素向农村有序流动,是弥合城乡居民消费差距、推进共同富裕的关键。首先构建包含城市、农村部门和代表性家庭的一般均衡模型,分析多维开放对城乡居... 在对外开放从“以市场换技术”向“以制度引创新”转型时期,通过深化多维开放带动资源要素向农村有序流动,是弥合城乡居民消费差距、推进共同富裕的关键。首先构建包含城市、农村部门和代表性家庭的一般均衡模型,分析多维开放对城乡居民消费差距的影响及技术扩散在其中发挥的作用机制。进一步,在测算中国30个省份的多维开放和技术扩散水平的基础上,通过构建计量模型实证检验多维开放、技术扩散与城乡居民消费差距之间的关系。研究发现,多维开放有助于缩小城乡居民消费差距。机制检验表明,多维开放可以通过技术扩散缩小城乡居民消费差距。异质性分析表明,多维开放各维度中,贸易开放、投资开放和旅游开放的城乡居民消费缩距效果显著,但劳务开放对城乡居民消费差距的影响在统计上不显著;多维开放对城乡居民消费差距的缩小效果仅在东部、产业结构高级化程度高和数字普惠金融水平较高的省份显著。进一步分析表明,多维开放对技术扩散和城乡居民消费差距的影响存在显著的空间溢出效应。因此,应优化多维开放的涉农服务,深化农业国际合作双向联动;推动各类主体对接国际先进技术,强化技术扩散的示范引领与人力资本支撑作用;统筹开放性资源调配与区域差异化策略,构建跨省域技术协作与物流网络。 展开更多
关键词 多维开放 城乡居民消费差距 技术扩散 空间溢出效应 共同富裕
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85MeV^(19)F离子辐照GaP的正电子湮没研究
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作者 王荣 徐勇军 +1 位作者 黄龙 朱升云 《核技术》 CAS CSCD 北大核心 2001年第4期274-276,共3页
用正电子湮没寿命技术研究了 2 .4× 10 15 cm2 和 2 .2× 10 16 cm2 85MeV19F离子辐照GaP的辐照效应。结果表明 ,辐照在GaP中产生浓度较高的单空位 。
关键词 辐照效应 正电子湮没 抗辐射性能 磷化镓半导体 氟19离子辐照
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温度和拉伸速率对硝酸酯增塑的GAP/CL–20固体推进剂拉伸力学行为的影响 被引量:1
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作者 周水平 吴芳 +1 位作者 唐根 庞爱民 《化学推进剂与高分子材料》 CAS 2016年第5期48-52,共5页
通过单轴拉伸实验获得了聚叠氮缩水甘油醚(GAP)/六硝基六氮杂异伍兹烷(CL–20)推进剂在–40-70℃和0.5-5 000 mm/min的拉伸速率(ν)下的应力–应变曲线。GAP/CL–20推进剂的力学性能呈现明显的温度(t)和拉伸效应,温度和拉伸的... 通过单轴拉伸实验获得了聚叠氮缩水甘油醚(GAP)/六硝基六氮杂异伍兹烷(CL–20)推进剂在–40-70℃和0.5-5 000 mm/min的拉伸速率(ν)下的应力–应变曲线。GAP/CL–20推进剂的力学性能呈现明显的温度(t)和拉伸效应,温度和拉伸的“耦合”作用,使推进剂的力学性能发生显著的变化。初始弹性模量和最大拉伸强度σm随t的降低与ν的升高逐渐增加,σm与lnν呈线性关系。与模量和强度相比,最大伸长率εm和断裂伸长率εb的变化规律较为复杂:低温时,推进剂的εm和εb与lnν呈二次方关系,并随t的上升,先上升后下降;高温时,推进剂的εm和εb与lnν呈线性关系,随t的上升显著下降。 展开更多
关键词 gap/CL-20推进剂 力学性能 耦合效应 拉伸速率 温度
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税优型个人养老金增大还是减小了收入差距?——基于共同富裕视角
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作者 马笑月 周延 《中央财经大学学报》 北大核心 2026年第1期61-77,共17页
完善分配制度是妥善解决收入差距问题、促进共同富裕的必然手段。为探究税优型第三支柱个人养老金政策对收入分配的影响,本文从共同富裕视角出发,区分中高收入群体与低收入群体,构建两期动态一般均衡模型,探讨个人养老金政策对于收入差... 完善分配制度是妥善解决收入差距问题、促进共同富裕的必然手段。为探究税优型第三支柱个人养老金政策对收入分配的影响,本文从共同富裕视角出发,区分中高收入群体与低收入群体,构建两期动态一般均衡模型,探讨个人养老金政策对于收入差距的影响。研究发现,第三支柱个人养老金缴费率以及收益率的提升会恶化收入分配与再分配状况;而适当提高领取税率则可能改善收入再分配状况。进一步研究发现,第三支柱个人养老金缴费率对于收入分配与再分配的影响最大,收益率次之。基于上述结论,本文提出差异化税收模式等政策建议,旨在降低低收入群体提取养老金时的税收负担,同时保留对高收入群体养老金收入的适度调节,从而在提升制度公平性的同时,兼顾财政可持续性。 展开更多
关键词 税优型个人养老金 经济效应 一般动态均衡 收入差距
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数字新质生产力对山区城乡收入差距的影响
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作者 陆雨 孔凡斌 徐彩瑶 《中国农业大学学报》 北大核心 2026年第1期253-275,共23页
为厘清数字新质生产力对山区城乡收入差距的影响,基于浙江省2011—2022年山区26县的面板数据,利用双向固定效应模型、中介效应模型和门槛效应模型,分析数字新质生产力与山区城乡收入差距的影响及作用机制。结果表明:1)数字新质生产力能... 为厘清数字新质生产力对山区城乡收入差距的影响,基于浙江省2011—2022年山区26县的面板数据,利用双向固定效应模型、中介效应模型和门槛效应模型,分析数字新质生产力与山区城乡收入差距的影响及作用机制。结果表明:1)数字新质生产力能够显著缩小山区城乡收入差距,且对农村居民收入的提升作用更显著;2)该影响存在区域和时间异质性,在生态发展县和发展深化期,其缩小城乡收入差距的作用更显著,而在跨越发展县和发展初期作用不显著;3)林业产业发展与就业结构是数字新质生产力影响城乡收入差距的主要机制路径,其中林业发展主要提升农村居民收入,而优化就业结构对城镇居民收入带动更强;4)信息化水平存在显著门槛效应,在信息化水平较低时,数字新质生产力的正向效应有限,甚至可能扩大城乡收入差距;在信息化水平较高时,数字新质生产力显著缩小山区城乡收入差距。应因地制宜推动数字新质生产力与林业产业融合发展,完善信息基础设施与就业支持机制,增强欠发达地区收入提升能力,促进山区城乡协调发展。 展开更多
关键词 数字新质生产力 林业产业发展 城乡收入差距 山区 门槛效应
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数字普惠金融影响城乡收入差距的效果研究——基于双固定空间杜宾模型的实证分析
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作者 何再秋 王全意 《中国商论》 2026年第2期105-109,共5页
随着数字普惠金融发展水平的日益提升,数据要素不断深化与其他生产要素的协同联动机制,将对城乡收入格局产生深远影响。本文基于我国2011—2023年31个省市面板数据,测算城乡收入泰尔指数,采用双固定空间杜宾模型进行实证检验。研究发现:... 随着数字普惠金融发展水平的日益提升,数据要素不断深化与其他生产要素的协同联动机制,将对城乡收入格局产生深远影响。本文基于我国2011—2023年31个省市面板数据,测算城乡收入泰尔指数,采用双固定空间杜宾模型进行实证检验。研究发现:(1)31个省市的数字普惠金融发展水平和城乡收入差距具有空间相关性,且数字普惠金融的发展总体上会显著扩大城乡收入差距;(2)异质性分析发现,西部地区数字普惠金融的发展会显著扩大城乡收入差距,而在东部地区和中部地区则起到一定程度的改善城乡收入不平等的作用;(3)机制检验表明,数字普惠金融通过影响数字发展水平和人力资本水平,进而缩小城乡收入差距。基于此,本文提出相关策略建议,以供参考。 展开更多
关键词 数字普惠金融 城乡收入差距 空间溢出效应 空间杜宾模型 高质量发展
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Gap效应对搜索目标显著性和绩效的影响 被引量:2
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作者 徐新然 郭肖亚 于瑞峰 《工业工程》 北大核心 2021年第1期117-122,共6页
探究了gap效应对视觉搜索任务中搜索目标的显著性和搜索绩效的影响。采用gap值(11种时间值)×极性(正极性和负极性)×角度(30°/60°,20°/70°)3因子组内设计实验,18名被试在不同gap值、极性和角度组合条件下... 探究了gap效应对视觉搜索任务中搜索目标的显著性和搜索绩效的影响。采用gap值(11种时间值)×极性(正极性和负极性)×角度(30°/60°,20°/70°)3因子组内设计实验,18名被试在不同gap值、极性和角度组合条件下完成一系列视觉搜索任务,测量指标为发现目标物的概率和反应时间。结果表明,gap值、角度及二者的交互作用对搜索目标的显著性有显著影响,gap值和极性对反应时间有显著影响,即gap效应对视觉搜索任务中搜索目标的显著性和搜索绩效均有显著影响。 展开更多
关键词 视觉搜索 显著性 gap效应 显示极性 人因工程
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东北三省农业企业集聚对城乡收入差距的影响
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作者 韩文瑞 吕国玮 周晓芊 《农业与技术》 2026年第1期234-242,共9页
缩小城乡收入差距是实现共同富裕的重要目标,农业企业集聚则是推进农业现代化的重要途径。研究农业企业集聚对城乡收入差距的影响,促进城乡均衡发展。基于东北三省34个地级及以上城市2001—2020年的企业注册大数据和面板数据,测度农业... 缩小城乡收入差距是实现共同富裕的重要目标,农业企业集聚则是推进农业现代化的重要途径。研究农业企业集聚对城乡收入差距的影响,促进城乡均衡发展。基于东北三省34个地级及以上城市2001—2020年的企业注册大数据和面板数据,测度农业企业集聚和城乡收入差距的时空演化特征,利用空间计量模型探索农业企业集聚对城乡收入差距的影响及空间效应。研究表明:东北三省的农业企业数量整体呈增长趋势,表现为“西南多、东北少”的空间集聚分布特征;城乡收入差距整体呈缩小趋势;集聚对城乡收入差距的影响存在空间溢出和滞后效应;大型、种植业企业集聚缩小本地的城乡收入差距,大型企业滞后期为3年;小微型或辅助活动企业滞后期分别是1年、4年,显著缩小邻近地区的城乡收入差距。因此,应优先引导种植业和大型农业企业集聚,促进向农村转移,释放外部效应;带动农业生产效率和农村产业产值提升,提高农民收入,实现共同富裕和区域协调发展。 展开更多
关键词 城乡收入差距 农业企业集聚 集聚效应 空间溢出 东北地区
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Study on Axial Flux Hysteresis Motors Considering Airgap Variation 被引量:1
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作者 Mohammad Modarres Abolfazl Vahedi Mohammadreza Ghazanchaei 《Journal of Electromagnetic Analysis and Applications》 2010年第4期252-257,共6页
Axial flux hysteresis motor (AFHM) is self-starting synchronous motor that uses the hysteresis characteristics of magnetic materials. It is known that the magnetic characteristics of hysteresis motor could be easily a... Axial flux hysteresis motor (AFHM) is self-starting synchronous motor that uses the hysteresis characteristics of magnetic materials. It is known that the magnetic characteristics of hysteresis motor could be easily affected by air gap and structure dimensions variation. Air gap length plays an important role in flux distribution in hysteresis ring and influences the output torque, terminal current, efficiency and even optimal value of other structural parameters of AFHM. Regarding this issue, in this study effect of air gap variation on performance characteristics of an axial flux hysteresis motor and effect of air gap length on hysteresis ring thickness and stator winding turns is investigated. Effect of air gap length on electrical circuit model is perused. Finally, simulation of AFHM in order to extract the output values of motor and sensitivity analysis on air gap variation is done using 3D-Finite Element Model. Hysteresis loop in the shape of an inclined ellipse is adopted. This study can help designers in design approach of such motors. 展开更多
关键词 HYSTERESIS LOOP AXIAL FLUX HYSTERESIS MOTOR 3D-FEM Model Complex PERMEABILITY Air gap effect
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LiF/GAP协同作用改善硼粉的燃烧性能
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作者 伍双艳 王吉权 +4 位作者 邵建 刘俊 陈九玉 朱宝忠 孙运兰 《火炸药学报》 EI CAS CSCD 北大核心 2024年第3期279-286,I0006,共9页
以氟化锂/缩水甘油叠氮化物聚合物(LiF/GAP)为界面层对微米硼进行改性,研究LiF/GAP协同作用对硼粉热行为、燃烧性能和凝聚相燃烧产物的影响。结果表明,通过硅烷偶联剂处理后,硼粉表面黏结性得以提高,LiF能够较好地包覆在硼粉表面;GAP在... 以氟化锂/缩水甘油叠氮化物聚合物(LiF/GAP)为界面层对微米硼进行改性,研究LiF/GAP协同作用对硼粉热行为、燃烧性能和凝聚相燃烧产物的影响。结果表明,通过硅烷偶联剂处理后,硼粉表面黏结性得以提高,LiF能够较好地包覆在硼粉表面;GAP在400℃之前抑制了LiF与硼表面氧化膜的反应,使LiF的除膜效应延后至硼粉氧化增重阶段,从而将更多的活性硼暴露在空气中发生氧化,促进了硼粉的燃烧;LiF和GAP协同作用显著改善了硼粉的燃烧性能,尤其当LiF和GAP质量分数均为10%时,作用效果最为明显。此外,LiF和GAP协同作用有效抑制了燃烧过程中硼粉团聚,使其凝聚相燃烧产物粒径降低。 展开更多
关键词 物理化学 硼颗粒 LiF/gap协同作用 燃烧特性 团聚抑制 燃烧机理
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