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Proton Conductivity of Ni, Y Co-Doped BaZrO<sub>3</sub>
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作者 Hiroya Morishita Yumiko Ikebe Eriko Ban 《Journal of Materials Science and Chemical Engineering》 2018年第6期19-27,共9页
Dense sintered bodies of proton conducting BaZrO3 (BZ) and Y-doped BaZrO3 (BZ-Y) were obtained at 1600℃ for a short sintering time of 5 hours, by the addition of NiO as a sintering promotion agent. The relative densi... Dense sintered bodies of proton conducting BaZrO3 (BZ) and Y-doped BaZrO3 (BZ-Y) were obtained at 1600℃ for a short sintering time of 5 hours, by the addition of NiO as a sintering promotion agent. The relative density and grain growth of samples, Ni-doped BaZrO3 (BZ-N) and Ni, Y co-doped BaZrO3 (BZ-NY), were increased with increasing Ni addition. The sinterability of BZ-NY was greatly improved just to add only 0.6 mol% Ni and the relative density of this sample was more than 98%, in contrast to that of 60% at most for BZ-Y without Ni addition. Electrical conductivity of BZ-NY added Ni 1.0 mol%, BaZr0.91Ni0.01Y0.08O3-α, was more than 10-3 S.cm-2 at 900℃?in a wet 1% hydrogen atmosphere, which value was 10 times higher than that of BZ-Y. In addition, the kind of electrical conduction carrier and an ionic transport number were also examined by employing various concentration cells. It was found that the proton conduction was dominant for both BZ-N and BZ-NY samples, although BZ-NY showed scarcely oxygenion conduction approximately 10% in a high temperature range higher than 800℃. From these results, as mall amount of Ni addition found to be effective for improvement of both the sinterability and the electrical conductivity. 展开更多
关键词 Proton Conducting Oxide Barium ZIRCONATE NI Y CO-DOPING Electrical Con-ductivity Ionic Transport Number
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The SPH approach to the process of container filling based on non-linear constitutive models 被引量:3
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作者 Tao Jiang Jie Ouyang +1 位作者 Lin Zhang Jin-Lian Ren 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第2期407-418,共12页
In this work, the transient free surface of con- tainer filling with non-linear constitutive equation's fluids is numerically investigated by the smoothed particle hydrody- namics (SPH) method. Specifically, the fi... In this work, the transient free surface of con- tainer filling with non-linear constitutive equation's fluids is numerically investigated by the smoothed particle hydrody- namics (SPH) method. Specifically, the filling process of a square container is considered for non-linear polymer fluids based on the Cross model. The validity of the presented SPH is first verified by solving the Newtonian fluid and Oldroyd- B fluid jet. Various phenomena in the filling process are shown, including the jet buckling, jet thinning, splashing or spluttering, steady filling. Moreover, a new phenomenon of vortex whirling is more evidently observed for the Cross model fluid compared with the Newtonian fluid case. 展开更多
关键词 non-linear. SPH Free surface Navier-Sto- kes FILLING
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Comparative Study of Linear and Non-Linear Controls of Three-Phase Shunt Active Filters for Improving the Quality of Electrical Energy
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作者 Mamane Adamou Nabil Alkassoum +1 位作者 André Foulani Amadou Seidou Maiga 《Energy and Power Engineering》 2019年第3期149-166,共18页
The aim of this work is to comparatively study two types of control of a three-phase shunt active filter (TSAF) in order to realize a system of depollution of electrical networks so as to improve the quality of electr... The aim of this work is to comparatively study two types of control of a three-phase shunt active filter (TSAF) in order to realize a system of depollution of electrical networks so as to improve the quality of electrical energy. We used two TSA control models which differ in the method of disturbed currents detection, one linear and the other non-linear. The results show that the non-linear control method, although with high calculation blocks, gives more promising results than the linear control method. When connecting a non-linear load (televisions, lamps, variable speed drives, etc.) directly to the public distribution network, the non-linear nature of the load causes the source current to be deformed due to the presence of harmonic currents and voltages. These harmonics thus generate a high reactive power, and therefore considerable electrical losses in the network. One of the solutions to reduce losses on the electricity grid is to incorporate an electronic circuit called a filter into the electricity grid. This work carried out a comparative study of two types of control of a three-phase shunt active filter (TSAF) in order to carry out a system for cleaning up electricity networks in order to improve the quality of electrical energy. We used two TSA control models that differ in the method of detecting disturbed currents, one linear and the other non-linear. The results show that the non-linear control method, although with high calculation blocks, gives better results than the linear control method. 展开更多
关键词 Power QUALITY Active THREE-PHASE SHUNT Filter non-linear CONTROL LINEAR CONTROL
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Impacts of LUCC processes on potential land productivity in China in the 1990s 被引量:22
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作者 LIU Jiyuan XU Xinliang +1 位作者 ZHUANG Dafang GAO Zhiqiang 《Science China Earth Sciences》 SCIE EI CAS 2005年第8期1259-1269,共11页
Using meteorological data and RS dynamic land-use observation data set, the po-tential land productivity that is limited by solar radiation and temperature is estimated and the impacts of recent LUCC processes on it a... Using meteorological data and RS dynamic land-use observation data set, the po-tential land productivity that is limited by solar radiation and temperature is estimated and the impacts of recent LUCC processes on it are analyzed in this paper. The results show that the influence of LUCC processes on potential land productivity change has extensive and unbal-anced characteristics. It generally reduces the productivity in South China and increases it in North China, and the overall effect is increasing the total productivity by 26.22 million tons. The farmland reclamation and original farmlands losses are the primary causes that led potential land productivity to change. The reclamation mostly distributed in arable-pasture and arable-forest transitional zones and oasises in northwestern China has made total productivity increase by 83.35 million tons, accounting for 3.50% of the overall output. The losses of original farmlands driven by built-up areas invading and occupying arable land are mostly distributed in the regions which have rapid economic development, e.g. Huang-Huai-Hai plain, Yangtze River delta, Zhu-jiang delta, central part of Gansu, southeast coastal region, southeast of Sichuan Basin and Urumqi-Shihezi. It has led the total productivity to decrease 57.13 million tons, which is 2.40% of the overall output. 展开更多
关键词 land-use change potential LAND productivity PHOTOSYNTHETIC productivity PHOTOSYNTHETIC THERMAL pro-ductivity total PHOTOSYNTHETIC THERMAL productivity.
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Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network
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作者 YÜNKÜL Kaan KARAÇOR Fatih +1 位作者 GÜRBÜZ Ayhan BUDAK TahsinÖmür 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3108-3122,共15页
This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results... This study aims to predict the undrained shear strength of remolded soil samples using non-linear regression analyses,fuzzy logic,and artificial neural network modeling.A total of 1306 undrained shear strength results from 230 different remolded soil test settings reported in 21 publications were collected,utilizing six different measurement devices.Although water content,plastic limit,and liquid limit were used as input parameters for fuzzy logic and artificial neural network modeling,liquidity index or water content ratio was considered as an input parameter for non-linear regression analyses.In non-linear regression analyses,12 different regression equations were derived for the prediction of undrained shear strength of remolded soil.Feed-Forward backpropagation and the TANSIG transfer function were used for artificial neural network modeling,while the Mamdani inference system was preferred with trapezoidal and triangular membership functions for fuzzy logic modeling.The experimental results of 914 tests were used for training of the artificial neural network models,196 for validation and 196 for testing.It was observed that the accuracy of the artificial neural network and fuzzy logic modeling was higher than that of the non-linear regression analyses.Furthermore,a simple and reliable regression equation was proposed for assessments of undrained shear strength values with higher coefficients of determination. 展开更多
关键词 Undrained shear strength Liquidity index Water content ratio non-linear regression Artificial neural networks Fuzzy logic
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Experimental study on electrical conductivity of dunite at high temperature and pressure——The evidence of electrical conductivity of cold mantle in the Gaize-Lugu area 被引量:5
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作者 WANG Duojun LI Heping +5 位作者 LIU Congqiang ZHAO Zhidan MO Xuanxue GUO Tieying SU Gengli DING Dongye 《Chinese Science Bulletin》 SCIE EI CAS 2001年第24期2089-2092,共4页
The electrical conductivities of the dunite from the Qinghai-Xizang (Tibetan) Plateau were measured with the impedance spectra method at 1.0-4.0 GPa and 643-1093 K. The experimental results indicated that activation e... The electrical conductivities of the dunite from the Qinghai-Xizang (Tibetan) Plateau were measured with the impedance spectra method at 1.0-4.0 GPa and 643-1093 K. The experimental results indicated that activation enthalpies of the dunite are smaller than 0.9 eV, the conduction mechanism in dunite may be attributed to the mixed electrical conduction involving grain interiors and boundaries. On the basis of the results of this experiment, we can deduce that there exists cold mantle in the area of Gaize-Lugu in the Qinghai-Xizang (Tibetan) Plateau by reverse methods from the magnetotelluric sounding data (conductivity-depths profile) available for western Tibet. The result provides the present cold mantle viewpoint with strong proof on the basis of high temperature and pressure experiments. 展开更多
关键词 high temperature and PRESSURE DUNITE electrical con- ductivity conduction mechanism COLD mantle.
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Microsphere femtosecond laser sub-50 nm structuring in far field via non-linear absorption 被引量:6
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作者 Zhenyuan Lin Kuan Liu +1 位作者 Tun Cao Minghui Hong 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第6期8-17,共10页
Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere... Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere femtosecond laser irradi-ation in far field.By varying laser fluence and scanning speed,nano-feature sizes can be flexibly tuned.Such small patterns are attributed to the co-effect of microsphere focusing,two-photons absorption,top threshold effect,and high-repetition-rate femtosecond laser-induced incubation effect.The minimum feature size can be reduced down to~30 nm(λ/26)by manipulating film thickness.The fitting analysis between the ablation width and depth predicts that the feature size can be down to~15 nm at the film thickness of~10 nm.A nano-grating is fabricated,which demonstrates desirable beam diffraction performance.This nano-scale resolution would be highly attractive for next-generation laser nano-lithography in far field and in ambient air. 展开更多
关键词 non-linear effect MICROSPHERE femtosecond laser far field
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Stochastic Models to Mitigate Sparse Sensor Attacks in Continuous-Time Non-Linear Cyber-Physical Systems
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作者 Borja Bordel Sánchez Ramón Alcarria Tomás Robles 《Computers, Materials & Continua》 SCIE EI 2023年第9期3189-3218,共30页
Cyber-Physical Systems are very vulnerable to sparse sensor attacks.But current protection mechanisms employ linear and deterministic models which cannot detect attacks precisely.Therefore,in this paper,we propose a n... Cyber-Physical Systems are very vulnerable to sparse sensor attacks.But current protection mechanisms employ linear and deterministic models which cannot detect attacks precisely.Therefore,in this paper,we propose a new non-linear generalized model to describe Cyber-Physical Systems.This model includes unknown multivariable discrete and continuous-time functions and different multiplicative noises to represent the evolution of physical processes and randomeffects in the physical and computationalworlds.Besides,the digitalization stage in hardware devices is represented too.Attackers and most critical sparse sensor attacks are described through a stochastic process.The reconstruction and protectionmechanisms are based on aweighted stochasticmodel.Error probability in data samples is estimated through different indicators commonly employed in non-linear dynamics(such as the Fourier transform,first-return maps,or the probability density function).A decision algorithm calculates the final reconstructed value considering the previous error probability.An experimental validation based on simulation tools and real deployments is also carried out.Both,the new technology performance and scalability are studied.Results prove that the proposed solution protects Cyber-Physical Systems against up to 92%of attacks and perturbations,with a computational delay below 2.5 s.The proposed model shows a linear complexity,as recursive or iterative structures are not employed,just algebraic and probabilistic functions.In conclusion,the new model and reconstructionmechanism can protect successfully Cyber-Physical Systems against sparse sensor attacks,even in dense or pervasive deployments and scenarios. 展开更多
关键词 Cyber-physical systems sparse sensor attack non-linear models stochastic models security
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The Existence of Meromorphic Solutions to Non-Linear Delay Differential Equations
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作者 Mingyue Wu 《Open Journal of Applied Sciences》 2023年第12期2329-2342,共14页
In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational c... In this paper, we study the existence of the transcendental meromorphic solution of the delay differential equations , where a(z) is a rational function, and are polynomials in w(z) with rational coefficients, k is a positive integer. Under the assumption when above equations own transcendental meromorphic solutions with minimal hyper-type, we derive the concrete conditions on the degree of the right side of them. Specially, when w(z)=0 is a root of , its multiplicity is at most k. Some examples are given here to illustrate that our results are accurate. 展开更多
关键词 non-linear Delay Differential Equations Painlevé Type Equations Nevanlinna Theory Meromorphic Function Solutions Minimal Hypertype
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滨海黏质盐渍土饱和泥浆与不同土水比土壤浸提液电导率的响应关系分析
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作者 王璐 胡鑫慧 +4 位作者 张岸清 郭洪海 郭徽 刘振林 贾曦 《山东农业科学》 北大核心 2024年第6期152-158,共7页
为统一和精准判定耐盐作物种植地块的土壤盐渍化程度,并针对饱和泥浆制备时饱和点的不确定性及其电导率测定的不稳定性等问题,本试验采用室内化验与统计分析方法,系统研究饱和泥浆与饱和土壤溶液两者间含水量和电导率的响应关系,以及饱... 为统一和精准判定耐盐作物种植地块的土壤盐渍化程度,并针对饱和泥浆制备时饱和点的不确定性及其电导率测定的不稳定性等问题,本试验采用室内化验与统计分析方法,系统研究饱和泥浆与饱和土壤溶液两者间含水量和电导率的响应关系,以及饱和泥浆电导率、全盐含量与土水比1∶0.5、1∶1、1∶2.5、1∶3.5、1∶5土壤浸提液电导率与全盐含量的响应和换算关系。结果表明:在滨海黏质盐渍土区,利用计算田间土壤孔隙度得到的饱和土壤溶液含水量、电导率不能直接代替饱和泥浆含水量、电导率,尽管二者的响应关系达到极显著水平;饱和泥浆电导率、全盐含量分别与土水比1∶1和1∶0.5土壤浸提液的数值差异最小,且与土水比1∶0.5~1∶5间各处理土壤浸提液的相应指标均呈极显著的响应关系;饱和泥浆电导率与土水比1∶5土壤浸提液的电导率、饱和泥浆全盐含量与土水比1∶1土壤浸提液全盐含量相关性最高,可分别用最佳拟合线性模型进行换算,模型分别为ECe(mS/cm)=5.406EC1∶5-0.284 4,TSe(g/kg)=0.836 4TS1∶1-0.135 9。 展开更多
关键词 黏质盐渍土 土水比 饱和泥浆 土壤浸提液 电导率 全盐含量
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从科技创新看全球经济前景——基于长周期视角
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作者 苏剑 杨盈竹 《南方经济》 CSSCI 北大核心 2024年第7期1-11,共11页
科技创新是扩大优质需求的根本方式,是驱动新一轮康波周期开启的关键力量。近年来,全球涌现了众多革命性的科技成果,包括星链系统、智能机器人、太空产业、量子计算、核聚变、室温超导等,带来生产力与生产方式的巨大变革,是未来推动全... 科技创新是扩大优质需求的根本方式,是驱动新一轮康波周期开启的关键力量。近年来,全球涌现了众多革命性的科技成果,包括星链系统、智能机器人、太空产业、量子计算、核聚变、室温超导等,带来生产力与生产方式的巨大变革,是未来推动全球经济持续繁荣的关键引擎。经济运行呈现周期性波动,根据周期长短可以划分为短周期、中周期和长周期,短周期主要受供给和需求影响,而长周期则依赖于创新驱动。因此,尽管短期内全球经济面临下行压力,但长期看全球经济将逐步进入新的经济长周期。新质生产力是生产力的高级形态,明确了新科技革命和产业变革的发展方向,培育新质生产力就是引导中国经济进入长周期,是经济高质量发展的必然要求。当前中国在新能源技术、人工智能技术和量子计算技术等领域已经取得显著优势,需要抓住本轮科技革命机遇加快培育新质生产力,依靠科技创新,特别是颠覆性、原创性创新,着眼于新制造、新服务、新业态,打造中国经济增长新动能、新优势,以科技创新驱动经济高质量发展。 展开更多
关键词 高质量发展 全球经济 长周期 科技创新 新质生产力
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Graphite Carbone Structure
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作者 Lahbib Abbas Lahcen Bih +3 位作者 Khalid Yamni Abderrahim Elyahyaouy Abdelmalik El Attaoui Zahra Ramzi 《Crystal Structure Theory and Applications》 2024年第1期1-10,共10页
Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-di... Carbon graphite is a crystalline form of carbon consisting of layers of hexagonal carbon atoms arranged in a two-dimensional “graphene” structure. Graphene layers are stacked on top of each other, forming a three-dimensional structure with a high degree of anisotropy. The carbon atoms within each layer are linked together by strong covalent bonds, creating a strong, stable lattice structure. However, the layers themselves are held together by weak van der Waals forces, enabling them to slide easily over each other. The properties of carbon graphite are highly dependent on the orientation and alignment of the graphene layers. When the layers are aligned parallel to each other, the material exhibits high strength and stiffness along the alignment direction, but is weaker and more flexible in other directions. Carbon graphite is used in a variety of applications where high strength, rigidity and electrical conductivity are required. Some common applications include electrical contacts, electric motor brushes, and as a structural material in aerospace and defense applications. The aim of our work is to describe the structure of graphite, its physical and chemical properties and its applications. 展开更多
关键词 GRAPHITE GRAPHENE Hexagonal Structure HARDNESS RIGIDITY Electrical Con-ductivity
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安全事业协同低空经济共赢新质生产力的理论研究
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作者 吴超 《安全》 2024年第11期52-61,共10页
为保障低空经济与安全事业协同发展,采用文献调查、历史分析、逻辑思辨、相似比较和预测分析等方法,对低空经济与安全事业的协同关系开展深入研究。简述低空经济的由来,梳理低空经济新技术在13个安全领域中的应用,阐述低空经济活动及其... 为保障低空经济与安全事业协同发展,采用文献调查、历史分析、逻辑思辨、相似比较和预测分析等方法,对低空经济与安全事业的协同关系开展深入研究。简述低空经济的由来,梳理低空经济新技术在13个安全领域中的应用,阐述低空经济活动及其技术带来的安全问题,提出有效的安全对策。研究结果表明:低空经济与安全事业关系重大,低空经济协同发展安全事业大有可为,安全工作者应尽快投入其中;低空经济新技术对各领域安全事业发展利大于弊,安全发展低空经济同时也发展了安全技术新质生产力;低空经济活动在安全管理方面可借鉴地面和民航的安全管理经验;从完善安全管理体系、夯实安全基础设施、培养安全人才及开办相关新专业方面提出低空经济安全发展的重要对策。 展开更多
关键词 低空经济 安全问题 安全事业 协同共赢 安全发展 新质生产力 无人机
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The ridgelet transform with non-linear threshold for seismic noise attenuation in marine carbonates 被引量:5
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作者 张恒磊 宋双 刘天佑 《Applied Geophysics》 SCIE CSCD 2007年第4期271-275,共5页
Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coeffici... Wavelet transforms have been successfully used in seismic data processing with their ability for local time - frequency analysis. However, identification of directionality is limited because wavelet transform coefficients reveal only three spatial orientations. Whereas the ridgelet transform has a superior capability for direction detection and the ability to process signals with linearly changing characteristics. In this paper, we present the issue of low signal-to-noise ratio (SNR) seismic data processing based on the ridgelet transform. Actual seismic data with low SNR from south China has been processed using ridgelet transforms to improve the SNR and the continuity of seismic events. The results show that the ridgelet transform is better than the wavelet transform for these tasks. 展开更多
关键词 Ridgelet transform DENOISE marine strata south China non-linear threshold
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Microstructure evolution of Al-Zn-Mg-Cu alloy during non-linear cooling process 被引量:3
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作者 李红英 刘蛟蛟 +2 位作者 余伟琛 赵辉 李德望 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第5期1191-1200,共10页
The microstructure evolution and properties of an Al-Zn-Mg-Cu alloy were investigated under different non-linear cooling processes from the solution temperature, combined with in-situ electrical resistivity measuremen... The microstructure evolution and properties of an Al-Zn-Mg-Cu alloy were investigated under different non-linear cooling processes from the solution temperature, combined with in-situ electrical resistivity measurements, selected area diffraction patterns (SADPs), transmission electron microscopy (TEM), and tensile tests. The relative resistivity was calculated to characterize the phase transformation of the experimental alloy during different cooling processes. The results show that at high temperatures, the microstructure evolutions change from the directional diffusion of Zn and Mg atoms to the precipitation of S phase, depending on the cooling rate. At medium temperatures, q phase nucleates on A13Zr dispersoids and grain boundaries under fast cooling conditions, while S phase precipitates under the slow cooling conditions. The strength and ductility of the aged alloy suffer a significant deterioration due to the heterogeneous precipitation in medium temperature range. At low temperatures, homogeneously nucleated GP zone, η′ and η phases precipitate. 展开更多
关键词 Al-Zn-Mg-Cu alloy microstructure evolution non-linear cooling electrical resistivity mechanical property
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Numerical Analysis of the Magnetic Dipole Effect on a Radiative Ferromagnetic Liquid Flowing over a Porous Stretched Sheet 被引量:1
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作者 G.Dharmaiah F.Mebarek-Oudina +1 位作者 K.S.Balamurugan N.Vedavathi 《Fluid Dynamics & Materials Processing》 EI 2024年第2期293-310,共18页
The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidflowing over a stretched surface in the presence of Brownian motion and thermophoresis are investigated.By means of a similarity t... The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidflowing over a stretched surface in the presence of Brownian motion and thermophoresis are investigated.By means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)method.The impact of various parameters,namely the velocity,temperature,concentration,is presented graphically.It is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanofluid and,consequently,the heat transfer.Comparison with earlier studies indicates high accuracy and effectiveness of the numerical approach.An increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary layer.The skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number. 展开更多
关键词 Brownian motion thermo-phoresis radiation magnetic dipole BVP4C non-linear
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以新质生产力推进共同富裕:逻辑机理与实现路径 被引量:5
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作者 杨二美 《党政研究》 北大核心 2024年第4期37-49,125,共14页
新质生产力是以创新为引力,以数智为驱动的新型生产力形态,其与共同富裕所要求的物质与精神财富极大增长、全体人民共同创造和分享财富的理念不谋而合。以新质生产力推动共同富裕,有助于生产力在规模、质量以及分配上实现新的突破。其一... 新质生产力是以创新为引力,以数智为驱动的新型生产力形态,其与共同富裕所要求的物质与精神财富极大增长、全体人民共同创造和分享财富的理念不谋而合。以新质生产力推动共同富裕,有助于生产力在规模、质量以及分配上实现新的突破。其一,新质生产力有利于推进共同富裕的物质积累机制;其二,新质生产力有利于推进共同富裕的精神文明引领机制;其三,新质生产力有利于推进共同富裕的普惠共享机制。未来需要进一步健全宏观调控机制、完善技术人才支撑体系、加快推动产业转型以及强化制度保障,将新质生产力与共同富裕紧密结合起来,通过发展新质生产力加快推进共同富裕。 展开更多
关键词 新质生产力 共同富裕 生产关系 生产力三要素 精神富裕
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交通运输用导电铝合金的应用现状及研究进展
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作者 王志琪 薛昊 +3 位作者 李佳铭 白俊源 赵志浩 秦高梧 《现代交通与冶金材料》 CAS 2024年第1期11-29,共19页
随着经济社会的不断发展,城市轨道交通建设以及电动汽车、新能源交通工具的逐渐普及,铝合金导线在交通运输网络的电力传输和交通装备运行等方面的用量日益增多,但铝合金导线因其本征的电阻在电力传输过程中仍存在着很大程度的能源损耗,... 随着经济社会的不断发展,城市轨道交通建设以及电动汽车、新能源交通工具的逐渐普及,铝合金导线在交通运输网络的电力传输和交通装备运行等方面的用量日益增多,但铝合金导线因其本征的电阻在电力传输过程中仍存在着很大程度的能源损耗,如何提升导电率的同时保证铝合金导体材料的强度是研究的长期难点。本文结合导电铝合金的发展现状及主要合金体系,探讨了铝合金导体材料的强度-电导率制约关系,总结了当前协同改善强度和导电率、制备高强高导铝合金的研究进展,归纳了几类主流的改善方法,即微合金化、热处理工艺优化、大塑性变形制备超细晶、制备铝基复合材料、熔体净化和提纯、沿平行电流方向引入细长晶等,最终展望了高强高导铝合金的未来发展。 展开更多
关键词 导电铝合金 微合金化 铝基复合材料 强度 电导率 细长晶
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蒙古沙冬青功能性状对土壤水分的响应
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作者 刘彤 唐逸芸 +2 位作者 杨宏玉 李蕾 石莎 《中央民族大学学报(自然科学版)》 2024年第1期28-35,共8页
植物功能性状是资源分配和生存繁殖的重要量化指标,反映了其对环境变化的响应与适应机制。本文通过测定固定沙地、砾质沙地两种生境下蒙古沙冬青(Ammopiptanthus mongolicus)个体形态特征、叶片功能性状以及花数量和花部结构特征,探究... 植物功能性状是资源分配和生存繁殖的重要量化指标,反映了其对环境变化的响应与适应机制。本文通过测定固定沙地、砾质沙地两种生境下蒙古沙冬青(Ammopiptanthus mongolicus)个体形态特征、叶片功能性状以及花数量和花部结构特征,探究其生长发育与繁殖过程中资源分配对不同土壤水分的响应规律。结果显示:(1)由于土壤水分含量的差异,砾质沙地上蒙古沙冬青的基径、冠幅、地上生物量显著大于固定沙地(P<0.05)。(2)不同土壤水分条件下,蒙古沙冬青叶面积、叶体积、叶组织密度具有显著差异性(P<0.05);比叶面积、叶鲜重、叶干重具有极显著差异性(P<0.01)。(3)土壤水分含量低的生境下,植株比叶面积与叶面积、叶体积显著正相关(P<0.05),与叶组织密度极显著负相关(P<0.001);土壤水分充足条件下,叶形指数与叶面积显著负相关(P<0.01)。异质生境下,叶干物质含量均与叶片含水量显著负相关(P<0.05),而与水分饱和亏、叶面积极显著正相关(P<0.001)。(4)土壤水分含量低的生境下,蒙古沙冬青花数量、花瓣长度与花萼大小均减小;异质生境下,花数量均与冠幅、地上生物量极显著正相关(P<0.001)。综上所述,蒙古沙冬青通过降低个体大小,减小叶面积和增加比叶面积、叶组织密度以及减少花数量适应干旱环境,功能性状与植物对资源的获取和利用密切相关,反映了其在异质生境下的生活史适应策略。 展开更多
关键词 蒙古沙冬青 土壤水分 个体大小 叶片功能性状 繁殖分配 生活史策略
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Assessing the effects of model parameter assumptions on surface-wave inversion results
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作者 Xuezhen Zhang Xiaodong Song 《Earthquake Science》 2024年第6期529-545,共17页
Surface-wave inversion is a powerful tool for revealing the Earth's internal structure.However,aside from shear-wave velocity(v_(S)),other parameters can influence the inversion outcomes,yet these have not been sy... Surface-wave inversion is a powerful tool for revealing the Earth's internal structure.However,aside from shear-wave velocity(v_(S)),other parameters can influence the inversion outcomes,yet these have not been systematically discussed.This study investigates the influence of various parameter assumptions on the results of surface-wave inversion,including the compressional and shear velocity ratio(v_(P)/v_(S)),shear-wave attenuation(Q_(S)),density(ρ),Moho interface,and sedimentary layer.We constructed synthetic models to generate dispersion data and compared the obtained results with different parameter assumptions with those of the true model.The results indicate that the v_(P)/v_(S) ratio,Q_(S),and density(ρ) have minimal effects on absolute velocity values and perturbation patterns in the inversion.Conversely,assumptions about the Moho interface and sedimentary layer significantly influenced absolute velocity values and perturbation patterns.Introducing an erroneous Mohointerface depth in the initial model of the inversion significantly affected the v_(S) model near that depth,while using a smooth initial model results in relatively minor deviations.The assumption on the sedimentary layer not only affects shallow structure results but also impacts the result at greater depths.Non-linear inversion methods outperform linear inversion methods,particularly for the assumptions of the Moho interface and sedimentary layer.Joint inversion with other data types,such as receiver functions or Rayleigh wave ellipticity,and using data from a broader period range or higher-mode surface waves,can mitigate these deviations.Furthermore,incorporating more accurate prior information can improve inversion results. 展开更多
关键词 shear-wave velocity model surface-wave inversion Moho interface sedimentary layer non-linear inversion
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