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Stable nanobubbles on ordered water monolayer near ionic model surfaces 被引量:1
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作者 Luyao Huang Cheng Ling +6 位作者 Limin Zhou Wenlong Liang Yujie Huang Lijuan Zhang Phornphimon Maitarad Dengsong Zhang Chunlei Wang 《Chinese Physics B》 2025年第1期143-148,共6页
The stable nanobubbles adhered to mineral surfaces may facilitate their efficient separation via flotation in the mining industry.However,the state of nanobubbles on mineral solid surfaces is still elusive.In this stu... The stable nanobubbles adhered to mineral surfaces may facilitate their efficient separation via flotation in the mining industry.However,the state of nanobubbles on mineral solid surfaces is still elusive.In this study,molecular dynamics(MD)simulations are employed to examine mineral-like model surfaces with varying degrees of hydrophobicity,modulated by surface charges,to elucidate the adsorption behavior of nanobubbles at the interface.Our findings not only contribute to the fundamental understanding of nanobubbles but also have potential applications in the mining industry.We observed that as the surface charge increases,the contact angle of the nanobubbles increases accordingly with shape transformation from a pancake-like gas film to a cap-like shape,and ultimately forming a stable nanobubble upon an ordered water monolayer.When the solid–water interactions are weak with a small partial charge,the hydrophobic gas(N_(2))molecules accumulate near the solid surfaces.However,we have found,for the first time,that gas molecules assemble a nanobubble on the water monolayer adjacent to the solid surfaces with large partial charges.Such phenomena are attributed to the formation of a hydrophobic water monolayer with a hydrogen bond network structure near the surface. 展开更多
关键词 NANOBUBBLES molecular dynamic simulation ordered water monolayer hydrogen bond network
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Ordered Clustering-Based Semantic Music Recommender System Using Deep Learning Selection
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作者 Weitao Ha Sheng Gang +2 位作者 Yahya D.Navaei Abubakar S.Gezawa Yaser A.Nanehkaran 《Computers, Materials & Continua》 2025年第5期3025-3057,共33页
Music recommendation systems are essential due to the vast amount of music available on streaming platforms,which can overwhelm users trying to find new tracks that match their preferences.These systems analyze users... Music recommendation systems are essential due to the vast amount of music available on streaming platforms,which can overwhelm users trying to find new tracks that match their preferences.These systems analyze users’emotional responses,listening habits,and personal preferences to provide personalized suggestions.A significant challenge they face is the“cold start”problem,where new users have no past interactions to guide recommendations.To improve user experience,these systems aimto effectively recommendmusic even to such users by considering their listening behavior and music popularity.This paper introduces a novel music recommendation system that combines order clustering and a convolutional neural network,utilizing user comments and rankings as input.Initially,the system organizes users into clusters based on semantic similarity,followed by the utilization of their rating similarities as input for the convolutional neural network.This network then predicts ratings for unreviewed music by users.Additionally,the system analyses user music listening behaviour and music popularity.Music popularity can help to address cold start users as well.Finally,the proposed method recommends unreviewed music based on predicted high rankings and popularity,taking into account each user’s music listening habits.The proposed method combines predicted high rankings and popularity by first selecting popular unreviewedmusic that themodel predicts to have the highest ratings for each user.Among these,the most popular tracks are prioritized,defined by metrics such as frequency of listening across users.The number of recommended tracks is aligned with each user’s typical listening rate.The experimental findings demonstrate that the new method outperformed other classification techniques and prior recommendation systems,yielding a mean absolute error(MAE)rate and rootmean square error(RMSE)rate of approximately 0.0017,a hit rate of 82.45%,an average normalized discounted cumulative gain(nDCG)of 82.3%,and a prediction accuracy of new ratings at 99.388%. 展开更多
关键词 Music recommender system order clustering deep learning
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Excellent dielectric response and microwave absorption in magnetic field-induced magnetic ordered structures
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作者 Zheng Xiu Fei Pan +7 位作者 Kai Yao Haojie Jiang Xiao Wang Lixin Li Jingli Wang Xiaona Ma Yang Yang Wei Lu 《Journal of Materials Science & Technology》 2025年第5期241-251,共11页
Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorp-tion(EMA)at a low filler loading(FL).The construction of one-dimensional magnetic metal fibers(1D-MMFs)contributes ... Weak interactions prevent the magnetic particles from achieving excellent electromagnetic wave absorp-tion(EMA)at a low filler loading(FL).The construction of one-dimensional magnetic metal fibers(1D-MMFs)contributes to the formation of an electromagnetic(EM)coupling network,enhancing EM properties at a low FL.However,precisely controlling the length of 1D-MMFs to regulate permittivity at low FL poses a challenge.Herein,a novel magnetic field-assisted growth strategy was used to fabricate Co-based fibers with adjustable permittivity and aspect ratios.With a variety of FL changes,centimeter-level Co long fibers(Co-lf)consistently exhibited higher permittivity than Co particles and Co short fibers due to the enhancement of the effective EM coupling.The Co-lf exhibits excellent EMA performance(-54.85 dB,5.8 GHz)at 10 wt.%FL.Meanwhile,heterogeneous interfaces were introduced to increase the interfacial polarization through a fine phosphorylation design,resulting in elevated EMA performances(-51.50 dB,6.6 GHz)at 10 wt.%FL for Co_(2)P/Co long fibers.This study improves the orderliness of the particle arrangement by regulating the length of 1D-MMFs,which affects the behavior of electrons inside the fibers,providing a new perspective for improving the EMA properties of magnetic materials at a low FL. 展开更多
关键词 Cobalt micro-fiber ordered structure Hierarchical structure Electromagnetic wave absorption
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Ordered structures with Schottky heterojunction functional unit regulate immune response and osteogenesis
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作者 Peng Yu Maofei Ran +7 位作者 Heying Ran Xuebin Yang Youzhun Fan Zhengao Wang Zhengnan Zhou Jinxia Zhai Zefeng Lin Chengyun Ning 《Journal of Materials Science & Technology》 2025年第10期276-287,共12页
Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration w... Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration when designing biomedical implants. In this research, ordered structures with Schottky heterojunction functional unit (OSSH) were constructed on titanium implant surfaces for bone regeneration regulation. The Schottky heterojunction functional unit is composed of periodically distributed titanium microdomain and titanium oxide microdomain with different carrier densities and surface potentials. The OSSH regulates the M2-type polarization of macrophages to a regenerative immune response by activating the PI3K-AKT-mTOR signal pathway and further promotes osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides fundamental insights into the biological effects driven by the Schottky heterojunction functional units that can electrically modulate osteogenesis. 展开更多
关键词 ordered structures with functional unit MACROPHAGE Implant OSTEOGENESIS Electric microenvironment
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Logically ordered control of organic room-temperature long-lived supramolecular luminophors
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作者 Xinhui Fan Yonghao Fan +10 位作者 Yuli Dang Puhui Xie Xin Li Zhanqi Cao Song Jiang Lijie Liu Xin Zheng Lixia Xie Caoyuan Niu Guoxing Liu Yong Chen 《Chinese Chemical Letters》 2025年第8期303-308,共6页
Herein,a ternary supramolecular assembly(BPP-BQ?CB[8]-SCD)is successfully constructed by a bromophenylpyridine-tethered-bromoisoquinoline(BPP-BQ),cucurbit[8]uril(CB[8])and sulfonatedβ-cyclodextrin(SCD)via successive ... Herein,a ternary supramolecular assembly(BPP-BQ?CB[8]-SCD)is successfully constructed by a bromophenylpyridine-tethered-bromoisoquinoline(BPP-BQ),cucurbit[8]uril(CB[8])and sulfonatedβ-cyclodextrin(SCD)via successive assembling way,exhibiting progressively enhanced green roomtemperature phosphorescence(RTP).The self-aggregates of BPP-BQ?CB[8]-SCD accommodate an energy acceptor rhodamine B(Rh B)to form a light-harvesting system(BPP-BQ?CB[8]-SCD@Rh B)with further enhanced yellow long-lifetime luminescence with large Stokes shift based on triplet-singlet F?rster resonance energy transfer(TS-FRET).Crucially,the introduction of a photoactive diarylethene achieves the long-lived photoluminescence of BPP-BQ?CB[8]-SCD@Rh B to be switched with the efficiency of up to98%through logically ordered lowering/enhancing RTP performance of the energy donor and intercepting/restoring TS-FRET pathway,when stimulated by host-vip competition and light illumination in sequence.Moreover,BPP-BQ?CB[8]-SCD@Rh B is evenly doped into polyvinyl alcohol or polyacrylamide to obtain high-performance luminescent films with long afterglow.The abovementioned logically ordered stimulus-switched long-lived emission enables the light-harvesting system in both solution and solid state to be applied in high-security-level information encryption and transformation,and anticounterfeiting. 展开更多
关键词 Supramolecular chemistry Logically ordered control Long-lived luminescentswitch TS-FRET Stepwise assembly RTP
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Eco-friendly synthesis coupled with predictive analytics:Developing hierarchical lignin-derived ordered mesoporous carbon for advanced supercapacitors
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作者 Xiaolan Zhao Xiaoqi Wang +5 位作者 Pei Gao Peng Zhao Jingjing Wang Yingna Li Zhibin Han Boxiong Shen 《Green Energy & Environment》 2025年第6期1256-1269,共14页
Hierarchical lignin-derived ordered mesoporous carbon(HOMC)was significant for advanced supercapacitors.However,achieving controllable fabrication and optimizing electrochemical behavior were challenging.In this work,... Hierarchical lignin-derived ordered mesoporous carbon(HOMC)was significant for advanced supercapacitors.However,achieving controllable fabrication and optimizing electrochemical behavior were challenging.In this work,an eco-friendly HOMC was synthesized using lignin as carbon precursors and Zn^(2+)as cross-linking and pore-forming agents,followed by KHCO_(3)activation,eliminating the need for toxic phenolic resins and acid treatments for metal removal.Machine learning technology,specifically an Artificial Neural Network(ANN model,was utilized to assist the experimental design and prediction.The ANN model suggested an ideal hierarchical structure and optimized oxygen level,achieved through the adjustment of Zn^(2+)additive concentration,carbonization temperature,and subsequent KHCO_(3)activation to maximize capacitance.The HOMC electrode,with a micropore-to-mesopore ratio(S_(micro)/S_(meso))of 1.01 and an oxygen content of 8.81 at%,acquired a specific capacitance of 362 F·g^(-1)at 0.5 A·g^(-1)in 6 mol·L^(-1)KOH electrolyte.The assembled HOMC//HOMC supercapacitor could afford a high energy density of 33.38 Wh·kg^(-1)with a corresponding specific power density of 300 W·kg^(-1)in TEATFB PC electrolyte.Meanwhile,the long-term cycle stability of 94.33%was achieved after 20,000 cycles.This work provides an ANN assisted strategy for the synthesis of HOMC,highlighting its potential to valorize biomass and agricultural waste in sustainable energy storag solutions. 展开更多
关键词 LIGNIN Biomass Hierarchical ordered mesoporous carbon Machine learning Artificial neural network SUPERCAPACITOR
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Research Progress of Abrasive Groups Ordered Grinding Wheels
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作者 Ye Guo Bing Chen +3 位作者 Zihao Liu Shiwei Sun Guoyue Liu Bing Guo 《Chinese Journal of Mechanical Engineering》 2025年第3期177-208,共32页
Because the grinding temperature is high when grinding using conventional disordered grinding wheels,the grinding quality improvement is limited when using single abrasive ordered grinding wheels,and the wheel prepara... Because the grinding temperature is high when grinding using conventional disordered grinding wheels,the grinding quality improvement is limited when using single abrasive ordered grinding wheels,and the wheel preparation process is complex and costly when using microstructured grinding wheels,abrasive groups ordered grinding wheels are widely investigated.However,there is a paucity of systematic analyses and comprehensive reviews focused on abrasive groups ordered grinding wheels.Therefore,this paper defines abrasive groups ordered grinding wheels and classifies them,based on their unique characteristics,into groups such as abrasive blocks ordered grinding wheel,fine grain structured grinding wheel,abrasive clusters ordered grinding wheel,and abrasive fibers ordered grinding wheel.We provide an overview of the latest advances in wheel structures,preparation methods,and abrasive selection for various types of abrasive groups ordered grinding wheels.Furthermore,we conduct a comparative analysis of the existing types,significant advantages,and challenges associated with the four types of abrasive groups ordered grinding wheels.Looking ahead,given the potential of abrasive groups ordered grinding wheels in reducing grinding force and temperature,we recommend further exploration of their application in combination with special processing techniques.This could pave the way for the development of machining processes that are more environmentally friendly,energy-efficient,and precise. 展开更多
关键词 Abrasive groups ordered grinding wheels Abrasive blocks Fine grain structured Abrasive clusters Abrasive fibers
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CoFe_(2)O_(4)/CoFe loaded 3D ordered hierarchical porous N-doped carbon for efficient oxygen reduction in Zn-air battery and hydrogen evolution
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作者 Xinlun Song Juan Zhang +3 位作者 Xiaogeng Feng Yan’ou Qi Junshuo Cui Ying Xiong 《Journal of Energy Chemistry》 2025年第7期220-230,共11页
Optimizing active sites and enhancing mass transfer capability are of paramount importance for the improvement of electrocatalyst activity.On this basis,CoFe_(2)O_(4)/CoFe nanoparticles(NPs)loaded N-doped carbon(NC)th... Optimizing active sites and enhancing mass transfer capability are of paramount importance for the improvement of electrocatalyst activity.On this basis,CoFe_(2)O_(4)/CoFe nanoparticles(NPs)loaded N-doped carbon(NC)that featured with interconnected three-dimensional(3D)ordered porous hierarchies(3DOM FeCo/NC)are prepared,and its electrocatalytic activity is studied.Due to the open structure of 3D ordered macro-pores that greatly improves the mass transfer capacity of the catalytic process and enhances the utilization of active sites inside the catalyst,as well as the uniform distribution of Fe and Co bimetallic sites on the porous skeleton,3DOM FeCo/NC exhibits superior bi-functional catalytic activities for both hydrogen evolution reaction(HER)and oxygen reduction reaction(ORR).The overpotential of HER is lower than that of commercial Pt/C when performed at high current density(>235 mA cm^(-2))in1.0 M KOH,and the half-wave potential(0.896 V)of ORR in 0.1 M KOH is also superior to that of 20% commercial Pt/C and most other similar catalysts.The effective utilization and synergistic effect of CoFe_(2)O_(4)and CoFe hetero-metallic sites remarkably enhance the electrocatalytic activity.Furthermore,3DOM FeCo/NC is assembled as an air electrode in Zn-air battery,and exhibits satisfactory maximum power density,open-circuit voltage,and charge/discharge stability over benchmark Pt/C+IrO_(2).This work contributes new insights into the design of transition-metal-based multifunctional catalysts,and has great potential for energy conversion and storage. 展开更多
关键词 3D ordered macro-pores Metal organic frameworks(MOFs) Hydrogen evolution reactions(HER) Oxygen reduction reactions(ORR) Zn-air battery
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基于Ordered Probit模型的交通事故受伤人数预测 被引量:24
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作者 宗芳 许洪国 张慧永 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2012年第7期41-45,56,共6页
建立了交通事故受伤人数预测的Ordered Probit模型,应用极大似然方法进行了模型标定.应用模型分析了受伤人数的影响因素,计算了各影响因素的边际贡献,并进行了受伤人数的预测.结果表明,对受伤人数影响较大的因素有路表是否干燥、是否有... 建立了交通事故受伤人数预测的Ordered Probit模型,应用极大似然方法进行了模型标定.应用模型分析了受伤人数的影响因素,计算了各影响因素的边际贡献,并进行了受伤人数的预测.结果表明,对受伤人数影响较大的因素有路表是否干燥、是否有大中型车辆、是否在交叉口.所建模型在进行事故受伤人数预测的同时,也可用于分析各因素对受伤人数的影响方向和影响程度.文中结果可为交通管理部门迅速准确地判断事故态势并做出快速响应提供决策支持. 展开更多
关键词 交通事故 ordered PROBIT模型 受伤人数 态势预测 快速响应
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我国老年人自评健康状况及其影响因素研究——基于ordered probit模型的估计 被引量:43
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作者 胡宏伟 李玉娇 《山西财经大学学报》 CSSCI 北大核心 2011年第2期1-8,共8页
基于2006年中国健康与营养调查(CHNS)的截面数据,描述了我国老年人的健康状况,利用Ordered Probit模型分析了影响老年人健康状况的因素,如个人身体特征、社会经济特征、自身行为和医疗保险可及性等,发现不同年龄、性别和户籍的老年人健... 基于2006年中国健康与营养调查(CHNS)的截面数据,描述了我国老年人的健康状况,利用Ordered Probit模型分析了影响老年人健康状况的因素,如个人身体特征、社会经济特征、自身行为和医疗保险可及性等,发现不同年龄、性别和户籍的老年人健康状况存在差异。 展开更多
关键词 老年人 自评健康 ordered PROBIT模型
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Synthesis of three-dimensional ordered mesoporous MnO_2 and its catalytic performance in formaldehyde oxidation 被引量:21
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作者 拜冰阳 乔琦 +1 位作者 李俊华 郝吉明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期27-31,共5页
Three-dimensional(3D)ordered mesoporous MnO2 was prepared using KIT-6 mesoporous molecular sieves as a hard template.The material was used for catalytic oxidation of HCHO.The material has high surface areas and the ... Three-dimensional(3D)ordered mesoporous MnO2 was prepared using KIT-6 mesoporous molecular sieves as a hard template.The material was used for catalytic oxidation of HCHO.The material has high surface areas and the mesoporous characteristics of the template,with cubic symmetry(ia3d).It consists of a β-MnO2 crystalline phase corresponding to pyrolusite,with a rutile structure.Transmission electron microscopy and X-ray photoelectron spectroscopy showed that the 3D-MnO2 catalyst has a large number of exposed Mn4+ ions on the(110)crystal plane surfaces,with a lattice spacing of 0.311 nm; this enhances oxidation of HCHO.Complete conversion of HCHO to CO2 and H2O was achieved at 130 °C on 3D-MnO2; the same conversions on α-MnO2 and β-MnO2 nanorods were obtained at 140 and 180 °C,respectively,under the same conditions.The specific mesoporous structure,high specific surface area,and large number of surface Mn4+ ions are responsible for the catalytic activity of 3D-MnO2 in HCHO oxidation. 展开更多
关键词 Three-dimensional ordered material Mesoporous structure Manganese oxide FORMALDEHYDE Catalytic oxidation
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图书馆微服务满意度的影响因素分析研究——基于Ordered Probit模型 被引量:5
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作者 白茹莉 谭文婷 《新世纪图书馆》 CSSCI 2018年第9期60-62,76,共4页
图书馆微服务是指借助微信、微博、移动app等互联网工具产生的一种新型服务,论文通过Ordered Probit模型分析图书馆微服务的影响因素,探讨图书馆如何充分利用微服务的各项功能,提升读者的使用体验和满意度。
关键词 图书馆微服务 满意度 ordered PROBIT模型
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我国高校军民融合科研创新影响因素研究——基于Ordered Logit模型的实证分析 被引量:7
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作者 何海燕 曹华伟 《科技进步与对策》 CSSCI 北大核心 2020年第10期146-151,共6页
为研究新时代背景下高校军民融合科研创新影响因素,在分析专家访谈和实地调研资料的基础上,通过问卷调查方法收集数据资料,运用Ordered Logit模型对其影响因素进行了实证分析,并研究了各影响因素对现阶段高校军民融合科研创新发展的影... 为研究新时代背景下高校军民融合科研创新影响因素,在分析专家访谈和实地调研资料的基础上,通过问卷调查方法收集数据资料,运用Ordered Logit模型对其影响因素进行了实证分析,并研究了各影响因素对现阶段高校军民融合科研创新发展的影响程度。研究表明,军民融合创新发展的国家战略、军产学研协同创新体系、军民融合科研人才支撑、军民融合科研创新的激励政策、军民融合科研成果知识产权保护等因素对我国高校军民融合科研创新发展面临的主要问题有显著影响。 展开更多
关键词 高校科研 军民融合 科研创新 ordered LOGIT模型
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Preparation and improved photocatalytic activity of ordered mesoporous TiO_2 by evaporation induced self-assembly technique using liquid crystal as template 被引量:2
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作者 刘晨 李佑稷 +2 位作者 徐鹏 李泽时 曾孟雄 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1072-1078,共7页
Ordered mesoporous TiO2 (OMPT) was prepared by an evaporation induced self-assembly technique using liquid crystal as template. The key factors affecting the methylene blue (MB) oxidation efficiency were investiga... Ordered mesoporous TiO2 (OMPT) was prepared by an evaporation induced self-assembly technique using liquid crystal as template. The key factors affecting the methylene blue (MB) oxidation efficiency were investigated, including the initial concentration of MB, pH value and catalyst concentration. The results show that the obtained OMPT has high thermal stability and shows a 2D hexagonal mesostructure with the small particle size and high surface area, which lead to higher degradation efficiency than commercial P25 or nanoparticle TiO2 (NPT) fabricated by sol-gel process. The optimal conditions are 5 mg/L MB, pH 6 and 1.5 g/L OMPT for the fastest rate of MB degradation. Total organic carbon (TOC) analysis indicates complete mineralization of MB in 240 min by OMPT, with rate constant higher than NPT or P25. 展开更多
关键词 TITANIA ordered mesopore liquid crystal template methylene blue degradation
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Effect of atomic structure on migration characteristic and solute segregation of ordered domain interfaces formed in Ni_(75)Al_xV_(25-x) 被引量:2
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作者 张明义 陈铮 +3 位作者 王永欣 马光 卢艳丽 范晓丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第3期604-611,共8页
Based on the microscopic phase-field model, ordered domain interfaces formed between D022 (Ni3V) phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migrati... Based on the microscopic phase-field model, ordered domain interfaces formed between D022 (Ni3V) phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migration characteristic and solute segregation of interfaces were studied. It is found that the migration ability is related to the atomic structure of interfaces, and three kinds of interfaces can migrate except the interface (001)//(002) which has the characteristic of L12 (Ni3Al) structure. V atoms jump to the nearest neighbor site and substitute for Ni, and vice versa. Because of the site selectivity behaviors of jumping atoms, the number of jumping atoms during the migration is the least and the jumping distance of atoms is the shortest among all possible modes, and the atomic structures of interfaces are unchanged before and after the migration. The preferences and degree of segregation or depletion of alloy elements are also related to the atomic structure of interface. 展开更多
关键词 atomic migration characteristic solute segregation site selectivity microscopic phase-field ordered domain interface
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基于Ordered Logistic模型的居民幸福感组群差异分析 被引量:6
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作者 姚晓军 孙美平 《统计与决策》 CSSCI 北大核心 2011年第6期83-85,共3页
文章以兰州市居民幸福感调查结果为数据源,应用Ordered Logistic模型对居民幸福感在若干变量上的组群差异进行了较系统的分析。结果表明,幸福感在性别、教育程度、婚姻状况、健康状况、家庭氛围、职业稳定变量上的组群差异显著,可以认... 文章以兰州市居民幸福感调查结果为数据源,应用Ordered Logistic模型对居民幸福感在若干变量上的组群差异进行了较系统的分析。结果表明,幸福感在性别、教育程度、婚姻状况、健康状况、家庭氛围、职业稳定变量上的组群差异显著,可以认为这些变量是影响当前兰州市居民幸福感的主要因素。提出了提高兰州市居民幸福感的政策建议。 展开更多
关键词 ordered LOGISTIC模型 幸福感组群差异 政策建议
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Microstructure and mechanical properties of Mg_(94)Zn_2Y_4 extruded alloy with long-period stacking ordered structure 被引量:3
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作者 刘欢 薛烽 +2 位作者 白晶 周健 孙扬善 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3598-3603,共6页
The microstructure and mechanical properties of Mg94Zn2Y4 extruded alloy containing long-period stacking ordered structures were systematically investigated by SEM and TEM analyses. The results show that the 18R-LPSO ... The microstructure and mechanical properties of Mg94Zn2Y4 extruded alloy containing long-period stacking ordered structures were systematically investigated by SEM and TEM analyses. The results show that the 18R-LPSO structure and α-Mg phase are observed in cast Mg94Zn2Y4 alloy. After extrusion, the LPSO structures are delaminated and Mg-slices with width of 50-200 nm are generated. By ageing at 498 K for 36 h, the ageing peak is attained andβ′phase is precipitated. Due to this novel precipitation, the microhardness ofα-Mg matrix increases apparently from HV108.9 to HV129.7. While the microhardness for LPSO structure is stabilized at about HV145. TEM observations and SAED patterns indicate that the β′ phase has unique orientation relationships betweenα-Mg and LPSO structures, the direction in the close-packed planes ofβ′precipitates perpendicular to that ofα-Mg and LPSO structures. The ultimate tensile strength for the peak-aged alloy achieves 410.7 MPa and the significant strength originates from the coexistence ofβ′precipitates and 18R-LPSO structures. 展开更多
关键词 Mg94Zn2Y4 alloy long-period stacking ordered structure PRECIPITATION ageing tensile property
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基于Ordered Probit模型的区域客运通道需求层次识别 被引量:1
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作者 李莉 丁宏飞 《重庆交通大学学报(自然科学版)》 CAS 北大核心 2014年第5期124-127,共4页
为保证区域客运通道运力资源的合理配置,选取客运需求层次为因变量,个人收入、出行目的、心理偏好为控制变量,建立了客运需求层次识别的Ordered Probit模型。根据成渝客运通道的相关调查数据,利用Stata软件的oprobit命令实现参数估计,... 为保证区域客运通道运力资源的合理配置,选取客运需求层次为因变量,个人收入、出行目的、心理偏好为控制变量,建立了客运需求层次识别的Ordered Probit模型。根据成渝客运通道的相关调查数据,利用Stata软件的oprobit命令实现参数估计,并借助MATLAB软件的插值技术,描绘出该通道内控制变量对因变量的作用效果变化特征三维图。结果表明:此需求层次识别模型可以良好的表征不同影响因素下旅客的需求层级。 展开更多
关键词 交通运输 区域客运通道 ordered PROBIT模型 需求层次
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Influence of Preparation Conditions on Structural Stability of Ordered Mesoporous Carbons Synthesized by Evaporation-induced Triconstituent Co-assembly Method 被引量:1
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作者 游波 杨俊 +3 位作者 雍国平 刘少民 谢卫 苏庆德 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第3期365-372,I0004,共9页
Various ordered mesoporous carbons (OMCs) have been prepared by evaporation-induced trieonstituent co-assembly method. Their mesostructural stability under different carbon content, aging time and acidity were conve... Various ordered mesoporous carbons (OMCs) have been prepared by evaporation-induced trieonstituent co-assembly method. Their mesostructural stability under different carbon content, aging time and acidity were conveniently monitored by X-ray diffraction, transmission electron microscopy, and N2 sorption isotherms techniques. The results show mesostruetural stability of OMCs is enhanced as the carbon content increases from 36% to 46%, further increasing carbon content deteriorates the mesostructural stability. Increasing aging time from 0.5 h to 5.0 h make the mesostructural stability go through an optimum (2.0 h) and gradually reduce framework shrinkage of the OMCs. Highly OMCs can only be obtained in the acidity range of 0.2-1.2 mol/L HC1, when the acidity is near the isoelectrie point of silica, the resulting OMCs have the best mesostructure stability. Under the optimum condition, the carbon content of 46%, aging time of 2.0 h, and 0.2 mol/L HCl, the resulting OMCs have the best mesostrueture stability and the highest BET surface areas of 2281 m2/g. 展开更多
关键词 Triblock copolymer Mesostructural stability SELF-ASSEMBLY ordered mesoporous carbon
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Synthesis of K-doped three-dimensionally ordered macroporous Mn_(0.5)Ce_(0.5)O_δ catalysts and their catalytic performance for soot oxidation 被引量:7
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作者 于学华 赵震 +4 位作者 韦岳长 刘坚 李建梅 段爱军 姜桂元 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1957-1967,共11页
A series of K-doped Mn0.5Ce0.5Oδ (K-MCO) catalysts with three-dimensionally ordered macroporous (3DOM) structure and different K loadings were successfully synthesized using simple methods. These catalysts exhibi... A series of K-doped Mn0.5Ce0.5Oδ (K-MCO) catalysts with three-dimensionally ordered macroporous (3DOM) structure and different K loadings were successfully synthesized using simple methods. These catalysts exhibited well-defined 3DOM nanostructure, which consisted of extensive interconnecting networks of spherical voids. The effects of the calcination temperature and calcination time on the morphological characteristics and crystalline forms of the catalysts were systematically studied. The catalysts showed high catalytic activity for the combustion of soot. 3DOM 20% K-MCO-4h catalyst, in particular, showed the highest catalytic activity of all of the catalysts studied (e.g., Ts0 = 331 ~C and Smco2 = 95.3%). The occurrence of structural and synergistic effects among the K, Mn, and Ce atoms in the catalysts was favorable for enhancing their catalytic activity towards the combustion of diesel soot. Furthermore, the temperatures required for the complete combustion of the soot (〈400 ℃) were well within the exhaust temperature range (175-400 ℃), which means that the accumulated soot can be removed under the conditions of the diesel exhaust gas. These catalysts could therefore be used in numerous practical applications because they are easy to synthesize, exhibit high catalytic activity, and can be made from low cost materials. 展开更多
关键词 Three-dimensionally ordered macroporous structureMn0.5Ce0.5Oδ catalystPotassuim dopingSoot combustion
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