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基于Ordered Probit模型的人车冲突安全影响因素研究
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作者 裴玉龙 杜小敏 沈威宇 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第3期181-187,共7页
为探究和定量分析人车冲突严重程度的影响因素,通过采集3个信号交叉口的人车冲突视频数据,利用T-Analyst标定人车轨迹并计算冲突指标(PET),采用85%位累计频率曲线法划分人车冲突等级;从人、车、路及环境特征中选取10个因素作为变量,构建... 为探究和定量分析人车冲突严重程度的影响因素,通过采集3个信号交叉口的人车冲突视频数据,利用T-Analyst标定人车轨迹并计算冲突指标(PET),采用85%位累计频率曲线法划分人车冲突等级;从人、车、路及环境特征中选取10个因素作为变量,构建Ordered Probit模型,以确立人车冲突严重程度的显著影响因素,并通过边际效应定量分析不同显著因素的影响程度。研究结果表明:行人闯红灯情况、年龄、行人交通量、人行道占用情况、人行道起点终点、车辆速度变化及车流量是人车冲突严重程度的显著因素,相较于各自参考量,行人闯红灯、车辆加速通过冲突点、人行道起点及老年人造成严重冲突的概率分别增加8.2%,5.9%,5.1%,4.4%;相较于低流量的交通流,较高流量的车流和行人交通流使得严重冲突的概率分别增加3.7%,2.5%,但人行道占用使得严重冲突的概率下降6.8%。研究结果可为信号交叉口行人过街交通安全设施的设计和实施提供理论依据。 展开更多
关键词 信号交叉口 行人安全 人车冲突严重度 ordered Probit模型 边际效应
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基于Ordered Logit模型的民办高校科研成果转化影响因素研究
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作者 张二丽 黄静 +1 位作者 王倩 陈彬彬 《河南财政金融学院学报(自然科学版)》 2024年第2期35-41,共7页
为研究民办高校科研成果转化影响因素,在专家访谈和实地调研的基础上,对K高校、C高校、B高校、Z高校等民办高校教师发放调查问卷收集数据,应用Ordered Logit模型对其影响因素进行了实证分析。分析发现,科研经费支持力度与科研成果数量... 为研究民办高校科研成果转化影响因素,在专家访谈和实地调研的基础上,对K高校、C高校、B高校、Z高校等民办高校教师发放调查问卷收集数据,应用Ordered Logit模型对其影响因素进行了实证分析。分析发现,科研经费支持力度与科研成果数量之间呈正相关关系,高校科研平台设置与服务地方经济建设之间呈正相关关系,高校科研管理制度与科研成果转化成效之间呈正相关关系。由此得出结论:我国民办高校科研成果转化与服务地方经济能力有待提升,民办高校科研成果转化的金融支持不够灵活、公共服务平台不够健全,完善民办高校科研管理制度是提高科研成果转化效率的重要保障。 展开更多
关键词 民办高校 科研成果 转化 ordered Logit模型
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Stable immobilization of lithium polysulfides using three-dimensional ordered mesoporous Mn_(2)O_(3) as the host material in lithium-sulfur batteries 被引量:1
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作者 Sung Joon Park Yun Jeong Choi +6 位作者 Hyun-seung Kim Min Joo Hong Hongjun Chang Janghyuk Moon Young-Jun Kim Junyoung Mun Ki Jae Kim 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期99-112,共14页
Lithium-sulfur batteries(LSBs)have drawn significant attention owing to their high theoretical discharge capacity and energy density.However,the dissolution of long-chain polysulfides into the electrolyte during the c... Lithium-sulfur batteries(LSBs)have drawn significant attention owing to their high theoretical discharge capacity and energy density.However,the dissolution of long-chain polysulfides into the electrolyte during the charge and discharge process(“shuttle effect”)results in fast capacity fading and inferior electrochemical performance.In this study,Mn_(2)O_(3)with an ordered mesoporous structure(OM-Mn_(2)O_(3))was designed as a cathode host for LSBs via KIT-6 hard templating,to effectively inhibit the polysulfide shuttle effect.OM-Mn_(2)O_(3)offers numerous pores to confine sulfur and tightly anchor the dissolved polysulfides through the combined effects of strong polar-polar interactions,polysulfides,and sulfur chain catenation.The OM-Mn_(2)O_(3)/S composite electrode delivered a discharge capacity of 561 mAh g^(-1) after 250 cycles at 0.5 C owing to the excellent performance of OM-Mn_(2)O_(3).Furthermore,it retained a discharge capacity of 628mA h g^(-1) even at a rate of 2 C,which was significantly higher than that of a pristine sulfur electrode(206mA h g^(-1)).These findings provide a prospective strategy for designing cathode materials for high-performance LSBs. 展开更多
关键词 host material lithium-sulfur battery ordered mesoporous structure shuttle effect transition-metal oxides
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Transformation of long-period stacking ordered structures in Mg-Gd-Y-Zn alloys upon synergistic characterization of first-principles calculation and experiment and its effects on mechanical properties 被引量:1
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作者 Mingyu Li Guangzong Zhang +4 位作者 Siqi Yin Changfeng Wang Ying Fu Chenyang Gu Renguo Guan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1867-1879,共13页
Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process... Based on experiments and first-principles calculations,the microstructures and mechanical properties of as-cast and solution treated Mg-10Gd-4Y-xZn-0.6Zr(x=0,1,2,wt.%)alloys are investigated.The transformation process of long-period stacking ordered(LPSO)structure during solidification and heat treatment and its effect on the mechanical properties of experimental alloys are discussed.Results reveal that the stacking faults and 18R LPSO phases appear in the as-cast Mg-10Gd-4Y-1Zn-0.6Zr and Mg-10Gd-4Y-2Zn-0.6Zr alloys,respectively.After solution treatment,the stacking faults and 18R LPSO phase transform into 14H LPSO phase.The Enthalpies of formation and reaction energy of 14H and 18R LPSO are calculated based on first-principles.Results show that the alloying ability of 18R is stronger than that of 14H.The reaction energies show that the 14H LPSO phase is more stable than the 18R LPSO.The elastic properties of the 14H and 18R LPSO phases are also evaluated by first-principles calculations,and the results are in good agreement with the experimental results.The precipitation of LPSO phase improves the tensile strength,yield strength and elongation of the alloy.After solution treatment,the Mg-10Gd-4Y-2Zn-0.6Zr alloy has the best mechanical properties,and its ultimate tensile strength and yield strength are 278.7 MPa and 196.4 MPa,respectively.The elongation of Mg-10Gd-4Y-2Zn-0.6Zr reaches 15.1,which is higher than that of Mg-10Gd-4Y0.6Zr alloy.The improving mechanism of elastic modulus by the LPSO phases and the influence on the alloy mechanical properties are also analyzed. 展开更多
关键词 Mg-Gd-Y-Zn alloys Long-period stacking ordered First-principles calculations ENTHALPIES Mechanical properties
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Enhanced activation of peroxymonosulfate by Fe/N co-doped ordered mesoporous carbon with dual active sites for efficient removal of m-cresol 被引量:1
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作者 Donghui Li Wenzhe Wu +6 位作者 Xue Ren Xixi Zhao Hongbing Song Meng Xiao Quanhong Zhu Hengjun Gai Tingting Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期130-144,共15页
The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,th... The novel Fe-N co-doped ordered mesoporous carbon with high catalytic activity in m-cresol removal was prepared by urea-assisted impregnation and simple pyrolysis method.During the preparation of the Fe-NC catalyst,the complexation of N elements in urea could anchor Fe,and the formation of C3N4during urea pyrolysis could also prevent migration and aggregation of Fe species,which jointly improve the dispersion and stability of Fe.The FeN4sites and highly dispersed Fe nanoparticles synergistically trigger the dual-site peroxymonosulfate (PMS) activation for highly efficient m-cresol degradation,while the ordered mesoporous structure of the catalyst could improve the mass transfer rate of the catalytic process,which together promote catalytic degradation of m-cresol by PMS activation.Reactive oxygen species (ROS) analytic experiments demonstrate that the system degrades m-cresol by free radical pathway mainly based on SO_(4)^(-)·and·OH,and partially based on·OH as the active components,and a possible PMS activation mechanism by 5Fe-50 for m-cresol degradation was proposed.This study can provide theoretical guidance for the preparation of efficient and stable catalysts for the degradation of organic pollutants by activated PMS. 展开更多
关键词 Degradation PEROXYMONOSULFATE Fe(II)/Fe(III)/FeN4 ordered mesopores carbon Catalyst Radical
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Lottery Numbers and Ordered Statistics
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作者 Kung-Kuen Tse 《Applied Mathematics》 2024年第4期287-291,共5页
The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typica... The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typically random and unpredictable. Some people use the lottery terminal randomly generates numbers for them, some players choose numbers that hold personal significance to them, such as birthdays, anniversaries, or other important dates, some enthusiasts have turned to statistical analysis as a means to analyze past winning numbers identify patterns or frequencies. In this paper, we use order statistics to estimate the probability of specific order of numbers or number combinations being drawn in future drawings. 展开更多
关键词 LOTTERY Order Statistics Hypergeometric Distribution EXPECTATION UNIFORM
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Influence of Local Cation Order on Electronic Structure and Optical Properties of Cation-Disordered Semiconductor AgBiS_(2)
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作者 Xiaoyu Wang Muhammad Faizan +5 位作者 Yuhao Fu Kun Zhou Yilin Zhang Xin He David J.Singh Lijun Zhang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期61-69,共9页
Site disorder exists in some practical semiconductors and can significantly impact their intrinsic properties both beneficially and detrimentally.However,the uncertain local order and structure pose a challenge for ex... Site disorder exists in some practical semiconductors and can significantly impact their intrinsic properties both beneficially and detrimentally.However,the uncertain local order and structure pose a challenge for experimental and theoretical research.Especially,it hinders the investigation of the effects of the diverse local atomic environments resulting from the site disorder.We employ the special quasi-random structure method to perform first-principles research on connection between local site disorder and electronic/optical properties,using cationdisordered AgBiS_(2)(rock salt phase)as an example.We predict that cation-disordered AgBiS_(2)has a bandgap ranging from 0.6 to 0.8 eV without spin-orbit coupling and that spin-orbit coupling reduces this by approximately 0.3 eV.We observe the effects of local structural features in the disordered lattice,such as the one-dimensional chain-like aggregation of cations that results in formation of doping energy bands near the band edges,formation and broadening of band-tail states,and the disturbance in the local electrostatic potential,which significantly reduces the bandgap and stability.The influence of these ordered features on the optical properties is confined to alterations in the bandgap and does not markedly affect the joint density of states or optical absorption.Our study provides a research roadmap for exploring the electronic structure of site-disordered semiconductor materials,suggests that the ordered chain-like aggregation of cations is an effective way to regulate the bandgap of AgBiS_(2),and provides insight into how variations in local order associated with processing can affect properties. 展开更多
关键词 stability structure ordered
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The Disintegration of a Floating Ferrofluid Layer into an Ordered Drop System in a Vertical Magnetic Field
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作者 Christina Khokhryakova Konstantin Kostarev Irina Mizeva 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2205-2218,共14页
Magnetic fluids,also known as ferrofluids,are versatile functional materials with a wide range of applications.These applications span from industrial uses such as vacuum seals,actuators,and acoustic devices to medica... Magnetic fluids,also known as ferrofluids,are versatile functional materials with a wide range of applications.These applications span from industrial uses such as vacuum seals,actuators,and acoustic devices to medical uses,including serving as contrast agents for magnetic resonance imaging(MRI),delivering medications to specific locations within the body,and magnetic hyperthermia for cancer treatment.The use of a non-wettable immiscible liquid substrate to support a layer of magnetic fluid opens up new possibilities for studying various fluid flows and related instabilities in multi-phase systems with both a free surface and an interface.The presence of two deformable boundaries within a ferrofluid layer significantly reduces the critical magnetic field strength required to transform the layer into an organized system of drops or polygonal figures evolving according to the intensity,frequency and direction of the considered magnetic field.This paper experimentally investigates this problem by assuming a uniform magnetic field perpendicular to the surface.This specific subject has not been previously explored experimentally.The critical magnetic field intensity required to destabilize the ferrofluid layer is determined based on the layer’s thickness and the fluid’s initial magnetic susceptibility.It is demonstrated that the critical magnetic field strength needed to disrupt the initially continuous ferrofluid layer increases with the layer’s thickness.Conversely,an increase in the ferrofluid’s magnetic susceptibility results in a decrease in the critical magnetic field strength.The emerging droplet structures are analyzed in terms of the number of drops,their size,and the periodicity of their arrangement.The number of droplets formed depends on the initial thickness of the layer,the presence or absence of a stable rupture in the upper layer,and the rate at which the magnetic field strength is increased to the critical value.A characteristic viscous time is proposed to evaluate the decomposition of the ferrofluid layer,which depends on the duration of the magnetic field’s application.The experimental data on the instability of a ferrofluid layer on a liquid substrate are compared with the theoretical results from the study of“magnetic fluid sandwich structures”conducted by Rannacher and Engel.This comparison highlights the similarities and differences between experimental observations and theoretical predictions,providing a deeper understanding of the behavior of ferrofluid layers under the influence of magnetic fields. 展开更多
关键词 FERROFLUID liquid substrate normal field instability ordered droplet structure
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Ordered mesoporous materials for water pollution treatment:Adsorption and catalysis
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作者 Peng Zhang Mingming He +4 位作者 Wei Teng Fukuan Li Xinyuan Qiu Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1239-1256,共18页
To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environment... To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions. 展开更多
关键词 Water pollution treatment ordered mesoporous materials Toxic contaminants ADSORPTION CATALYSIS
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Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers
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作者 Kaili Wang Tingting Zhou +4 位作者 Zhen Cao Zhimin Yuan Hongyan He Maohong Fan Zaiyong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1336-1365,共30页
The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, iono... The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future. 展开更多
关键词 PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading
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Scanning transmission electron microscopy and atom probe tomography analysis of non-stoichiometry long-period-stacking-ordered structures in Mg-Ni-Y/Sm alloys
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作者 Yimeng Chen Manuel Legrée +1 位作者 Jean-Louis Bobet Alexander Kvit 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期954-965,共12页
The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg alloys.The current work employs high angle annular dark field-scanning transmission electron microscopy(... The long-period-stacking-ordered(LPSO)structure affects the mechanical,corrosion and hydrolysis properties of Mg alloys.The current work employs high angle annular dark field-scanning transmission electron microscopy(HAADF-STEM)and atom probe tomography(APT)to investigate the structural and local chemical information of LPSO phases formed in Mg-Ni-Y/Sm ternary alloys after extended isothermal annealing.Depending on the alloying elements and their concentrations,Mg-Ni-Y/Sm develops a two-phase LPSO+α-Mg structure in which the LPSO phase contains defects,hybrid LPSO structure,and Mg insertions.HAADF-STEM and APT indicate non-stoichiometric LPSO with incomplete Ni_(6)(Y/Sm)_(8) clusters.In addition,the APT quantitatively determines the local composition of LPSO and confirms the presence of Ni within the Mg bonding layers.These results provide insight into a better understanding of the structure and hydrolysis properties of LPSO-Mg alloys. 展开更多
关键词 Magnesium alloys Long-range ordering Atom probe tomography(APT) STEM HAADF Hydrolysis properties.
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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia:highly active catalysts for n-hexane combustion
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作者 Xiuqing Hao Yuxi Liu +4 位作者 Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第7期1122-1137,共16页
Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile... Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds(VOCs).In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom(Co_(1)Ni_(1)/meso-Cr_(2)O_(3))and bimetallic Co and Ni nanoparticle(Co_(NP)Ni_(NP)/mesoCr_(2)O_(3))catalysts adopting the one-pot polyvinyl pyrrolidone(PVP)-and polyvinyl alcohol(PVA)-protecting approaches,respectively.The results indicate that the Co_(1)Ni_(1)/meso-Cr_(2)O_(3)catalyst exhibited the best catalytic activity for n-hexane(C_(6)H_(14))combustion(T_(50%)and T_(90%)were 239 and 263℃ at a space velocity of 40,000 mL g^(-1)h^(-1);apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol^(-1)and 4.3×10^(-7)mol g^(-1)_(cat)s^(-1),respectively),which was associated with its higher(Cr^(5+)+Cr^(6+))amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni_(1) was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co_(1) preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen(MvK)mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→CO_x→CO_(2)and H_(2)O. 展开更多
关键词 Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt-nickel single atoms n-Hexane combustion Catalytic reaction mechanism
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Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells
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作者 Enping Wang Liuxuan Luo +12 位作者 Yong Feng Aiming Wu Huiyuan Li Xiashuang Luo Yangge Guo Zehao Tan Fengjuan Zhu Xiaohui Yan Qi Kang Zechao Zhuang Daihui Yang Shuiyun Shen Junliang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期157-165,I0005,共10页
The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction... The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts. 展开更多
关键词 Platinum Cobalt Manganese Oxygen reduction reaction ordered intermetallic L1_(2)atomic structure Proton-exchange membrane fuel cell
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Mesoporous Carbon Nanofibers Loaded with Ordered PtFe Alloy Nanoparticles for Electrocatalytic Nitrate Reduction to Ammonia
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作者 XIE Meng LUO Wei QIU Pengpeng 《Journal of Donghua University(English Edition)》 CAS 2024年第4期365-376,共12页
Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we... Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we prepared mesoporous carbon nanofibers(mCNFs)functionalized with ordered PtFe alloys(O-PtFe-mCNFs)by a composite micelle interface-induced co-assembly method using poly(ethylene oxide)-block-polystyrene(PEO-b-PS)as a template.When employed as electrocatalysts,O-PtFe-mCNFs exhibited superior electrocatalytic performance for the NO_(3RR)compared to the mCNFs functionalized with disordered PtFe alloys(D-PtFe-mCNFs).Notably,the NH_(3)production performance was particularly outstanding,with a maximum NH_(3)yield of up to 959.6μmol/(h·cm~2).Furthermore,the Faraday efficiency(FE)was even 88.0%at-0.4 V vs.reversible hydrogen electrode(RHE).This finding provides compelling evidence of the potential of ordered PtFe alloy catalysts for the electrocatalytic NO_(3)RR. 展开更多
关键词 ordered PtFe alloy mesoporous carbon nanofiber(mCNF) nitrate reduction reaction(NO3RR) ammonia(NH3)production reaction
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移动设备用户的数字素养对信息安全保护意愿和行为的影响研究——基于 Ordered Probit 模型的估计 被引量:1
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作者 曹振祥 储节旺 《情报杂志》 CSSCI 北大核心 2023年第11期199-206,F0003,共9页
[研究目的]数字素养作为数字经济时代社会公众的核心素养,为移动设备用户的信息安全保护意愿和行为的研究提供新的思路和动力。[研究方法]从理论层面探讨移动设备用户数字素养对信息安全保护意愿和行为的影响效应及其传导路径,并基于实... [研究目的]数字素养作为数字经济时代社会公众的核心素养,为移动设备用户的信息安全保护意愿和行为的研究提供新的思路和动力。[研究方法]从理论层面探讨移动设备用户数字素养对信息安全保护意愿和行为的影响效应及其传导路径,并基于实际调查数据,运用Ordered Probit模型,对影响效应和传导路径进行实证检验。[研究结论]研究发现:移动设备用户的数字素养显著促进了信息安全保护意愿和行为,在考虑内生性问题之后,研究结论依然成立,且促进效应更为明显;反应效能和自我效能在数字素养影响信息安全保护意愿和行为间起传导作用,感知威胁的传导作用则不显著;提升移动设备用户的数字素养水平能够缩小信息安全保护意愿与行为之间的差异,有助于用户将信息安全保护意愿转化为保护行为;通过更换自变量测度方式及替换估计方法进行稳健性检验,结论仍然成立。 展开更多
关键词 移动设备用户 数字素养 信息安全保护意愿 信息安全保护行为 传导机制 ordered Probit
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跨境电商出口满意度的影响研究——基于ORDERED、LOGIT方法的实证分析
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作者 谭文婷 傅智园 《江苏商论》 2023年第5期58-61,73,共5页
本文使用欧洲晴雨表(Eurobarometer)数据,运用Ordered Logit模型计量方法对跨境电商满意度的影响因素感进行了研究。实证结果表明,个体因素中年纪、收入对于跨境购物满意度没有显著影响;物流因素包邮、丢件率、物流准时送达等因素提高... 本文使用欧洲晴雨表(Eurobarometer)数据,运用Ordered Logit模型计量方法对跨境电商满意度的影响因素感进行了研究。实证结果表明,个体因素中年纪、收入对于跨境购物满意度没有显著影响;物流因素包邮、丢件率、物流准时送达等因素提高跨境购物满意度的概率;品牌认知度和互联网信任度与跨境购物满意度显著正相关;个体样本数据而言欧盟男性整体比女性对于跨境购买更满意,但涉及到收入、包邮等其他因素,丢包、物流准时送达等因素更能提高女性对跨境购物满意度的概率。因此,跨境电商的发展应该完善物流系统、尽快确立信任机制。便捷当地支付方式等措施提高跨境购物满意度,进而提高我国跨境电商的出口。 展开更多
关键词 跨境电商 满意度 有序Logit 边际效应
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Whole petroleum system and ordered distribution pattern of conventional and unconventional oil and gas reservoirs 被引量:21
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作者 Cheng-Zao Jia Xiong-Qi Pang Yan Song 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期1-19,共19页
The classical source-to-trap petroleum system concept only considers the migration and accumulation of conventional oil and gas in traps driven dominantly by buoyance in a basin,although revised and improved,even some... The classical source-to-trap petroleum system concept only considers the migration and accumulation of conventional oil and gas in traps driven dominantly by buoyance in a basin,although revised and improved,even some new concepts as composite petroleum system,total petroleum system,total composite petroleum system,were proposed,but they do not account for the vast unconventional oil and gas reservoirs within the system,which is not formed and distributed in traps dominantly by buoyancedriven.Therefore,the petroleum system concept is no longer adequate in dealing with all the oil and gas accumulations in a basin where significant amount of the unconventional oil and gas resources are present in addition to the conventional oil and gas accumulations.This paper looked into and analyzed the distribution characteristics of conventional and unconventional oil/gas reservoirs and their differences and correlations in petroliferous basins in China and North America,and then proposed whole petroleum system(WPS)concept,the WPS is defined as a natural system that encompasses all the conventional and unconventional oil and gas,reservoirs and resources originated from organic matter in source rocks,the geological elements and processes involving the formation,evolution,and distribution of these oil and gas,reservoirs and resources.It is found in the WPS that there are three kinds of hydrocarbons dynamic fields,three kinds of original hydrocarbons,three kinds of reservoir rocks,and the coupling of these three essential elements lead to the basic ordered distribution model of shale oil/gas reservoirs contacting or interbeded with tight oil/gas reservoirs and separated conventional oil/gas reservoirs from source rocks upward,which is expressed as“S\T-C”.Abnormal conditions lead to other three special ordered distribution models:The first is that with shale oil/gas reservoirs separated from tight oil/gas reservoirs.The second is that with two direction ordered distributions from source upward and downward.The third is with lateral distribution from source outside. 展开更多
关键词 Conventional and unconventional oil and gas Petroleum system Whole petroleum system Hydrocarbon reservoirs ordered distribution model Fossil energy
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Highly Ordered Thermoplastic Polyurethane/Aramid Nanofiber Conductive Foams Modulated by Kevlar Polyanion for Piezoresistive Sensing and Electromagnetic Interference Shielding 被引量:6
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作者 Kunpeng Qian Jianyu Zhou +4 位作者 Miao Miao Hongmin Wu Sineenat Thaiboonrod Jianhui Fang Xin Feng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期335-352,共18页
Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevla... Highly ordered and uniformly porous structure of conductive foams is a vital issue for various functional purposes such as piezoresistive sensing and electromagnetic interference(EMI) shielding. With the aids of Kevlar polyanionic chains, thermoplastic polyurethane(TPU) foams reinforced by aramid nanofibers(ANF) with adjustable pore-size distribution were successfully obtained via a nonsolvent-induced phase separation. In this regard, the most outstanding result is the in situ formation of ANF in TPU foams after protonation of Kevlar polyanion during the NIPS process. Furthermore, in situ growth of copper nanoparticles(Cu NPs) on TPU/ANF foams was performed according to the electroless deposition by using the tiny amount of pre-blended Ti_(3)C_(2)T_(x) MXene as reducing agents. Particularly, the existence of Cu NPs layers significantly promoted the storage modulus in 2,932% increments, and the well-designed TPU/ANF/Ti_(3)C_(2)T_(x) MXene(PAM-Cu) composite foams showed distinguished compressive cycle stability. Taking virtues of the highly ordered and elastic porous architectures, the PAM-Cu foams were utilized as piezoresistive sensor exhibiting board compressive interval of 0–344.5 kPa(50% strain) with good sensitivity at 0.46 kPa^(-1). Meanwhile,the PAM-Cu foams displayed remarkable EMI shielding effectiveness at 79.09 dB in X band. This work provides an ideal strategy to fabricate highly ordered TPU foams with outstanding elastic recovery and excellent EMI shielding performance, which can be used as a promising candidate in integration of satisfactory piezoresistive sensor and EMI shielding applications for human–machine interfaces. 展开更多
关键词 Highly ordered conductive foams MXene NANOFIBER Thermoplastic Kevlar polyanion Piezoresistive sensing Electromagnetic interference shielding
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Ultrasmall NiS_(2)Nanocrystals Embedded in Ordered Macroporous Graphenic Carbon Matrix for Efficiently Pseudocapacitive Sodium Storage 被引量:1
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作者 Zhaozhao Liu Jiang Wang +7 位作者 Ran Bi Pinyi Zhao Mengqian Wu Xinyu Liu Likun Yin Chengyang Wang Mingming Chen Kemeng Ji 《Transactions of Tianjin University》 EI CAS 2023年第2期89-100,共12页
Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance betw... Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance between slow Na^(+)reaction kinetics of battery-type anodes and rapid ion adsorption/desorption of capacitive cathodes is a significant challenge.Here,we propose the high-rate-performance NiS_(2)@OMGC anode material composed of monodispersed NiS_(2) nanocrystals(8.8±1.7 nm in size)and N,S-co-doped graphenic carbon(GC).The NiS_(2)@OMGC material has a three-dimensionally ordered macroporous(3DOM)morphology,and numerous NiS_(2) nanocrystals are uniformly embedded in GC,forming a core-shell structure in the local area.Ultrafine NiS_(2) nanocrystals and their nano-microstructure demonstrate high pseudocapacitive Na-storage capability and thus excellent rate performance(355.7 mAh/g at 20.0 A/g).A SIHC device fabricated using NiS_(2)@OMGC and commercial activated carbon(AC)cathode exhibits ultrahigh energy densities(197.4 Wh/kg at 398.8 W/kg)and power densities(43.9 kW/kg at 41.3 Wh/kg),together with a long life span.This outcome exemplifies the rational architecture and composition design of this type of anode material.This strategy can be extended to the design and synthesis of a wide range of high-performance electrode materials for energy storage applications. 展开更多
关键词 Sodium-ion battery Sodium-ion hybrid capacitor Three-dimensionally ordered macroporous structure Graphenic carbon NiS_(2)nanocrystals
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Unitariness in Ordered Semigroups
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作者 Michael Tsingelis 《Applied Mathematics》 2023年第8期531-543,共13页
We introduce the concepts of unitary, almost unitary and strongly almost unitary subset of an ordered semigroup. For the notions of almost unitary and strongly almost unitary subset of an ordered semigroup, we use the... We introduce the concepts of unitary, almost unitary and strongly almost unitary subset of an ordered semigroup. For the notions of almost unitary and strongly almost unitary subset of an ordered semigroup, we use the notion of translational hull of an ordered semigroup. If (S,⋅,≤) is an ordered semigroup having an element e such that e ≤ e<sup>2</sup> and U is a nonempty subset of S such that u ≤ eu, u ≤ ue for all u ∈ U, we show that U is almost unitary in S if and only if U is unitary in . Also if (S,⋅,≤) is an ordered semigroup, e ∉ S, U is a nonempty subset of S, S<sup>e</sup>:= S ∪ {e} and U<sup>e</sup>:= U ∪ {e}, we give conditions that an (“extension” of S) ordered semigroup and the subset U<sup>e</sup> of S<sup>e</sup> must satisfy in order for U to be almost unitary or strongly almost unitary in S (in case U is strongly almost unitary in S, then the given conditions are equivalent). 展开更多
关键词 Left (Right) Translation of an ordered Semigroup Bitranslation of an ordered Semigroup Translational Hull of an ordered Semigroup Unitary Subset of an ordered Semigroup Almost Unitary Subset of an ordered Semigroup Strongly almost Unitary Subset of an ordered Semigroup
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