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Effect of phosphorus content on interfacial heat transfer and film deposition behavior during the high-temperature simulation of strip casting

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1016-1025页

作者： Wanlin Wang Cheng Lu Liang Hao jie zeng Lejun Zhou Xinyuan Liu Xia Li Chenyang Zhu School of Metallurgy and Environment Central South UniversityChangsha 410083China National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083China Institute of Research of Iron and Steel ShasteelJiangsu ProvinceZhangjiagang 215625China

The interfacial wettability and heat transfer behavior are crucial in the strip casting of high phosphorus-containing steel.A hightemperature simulation of strip casting was conducted using the droplet solidification technique with the aims to reveal the effects of phosphorus content on interfacial wettability,deposited film,and interfacial heat transfer *** showed that when the phosphorus content increased from 0.014wt%to 0.406wt%,the mushy zone enlarged,the complete solidification temperature delayed from1518.3 to 1459.4℃,the final contact angle decreased from 118.4°to 102.8°,indicating improved interfacial contact,and the maximum heat flux increased from 6.9 to 9.2 MW/*** the phosphorus content from 0.081wt%to 0.406wt%also accelerated the film deposition rate from 1.57 to 1.73μm per test,resulting in a thickened naturally deposited film with increased thermal resistance that advanced the transition point of heat transfer from the fifth experiment to the third experiment.

关键词： strip casting interfacial heat transfer interfacial wettability naturally deposited film phosphorus content

Evolution of interfacial heat transfer,contact behavior and microstructure during sub-rapid solidification of molten steel with different hydrogen contents

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Journal of Iron and Steel Research(International) 2024年第1期31卷 215-223页

作者： Cheng Lu Wan-lin Wang Chen-yang Zhu jie zeng Xin-yuan Liu Hua-long Li School of Metallurgy and Environment Central South UniversityChangsha410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha410083HunanChina Institute of Research of Iron and Steel ShasteelZhangjiagang215625JiangsuChina

Typical Q235 low-carbon steel samples with different hydrogen contents(0.0004,0.0008,and 0.0013 wt.%)were prepared by adjusting the environment humidity and *** effects of hydrogen on interfacial heat transfer,contact behavior,and microstructure evolution were investigated using a novel droplet solidification *** results revealed that when the hydrogen content increases from 0.0004 to 0.0013 wt.%,the maximum heat flux between the molten steel and cooling substrate decreases from 8.01 to 6.19 MW/m^(2),and the total heat removed in the initial 2 s reduces from 10.30 to 8.27 MJ/m^(2).Moreover,the final contact angle between the molten steel and substrate increases from 103.741°to 113.697°,and the number of pores on the droplet bottom surface increases significantly from 21 to 210 with the increase in *** surface roughness of the droplet bottom surface increases from 20.902 to 49.181 *** addition,the average grain size of the droplet increases from 14.778 to 33.548 pm with the increase in the hydrogen *** interfacial contact condition becomes worse due to the escape of hydrogen from the steel matrix during the cooling process,which leads to the reduction in the interfacial heat transfer and the increase in the grain size.

关键词： Strip casting Hydrogen content Interfacial heat transfer behavior Contact behavior Microstructure evolution

Slope-climbing of cropland and its effects in China

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Journal of Mountain Science 2024年第8期21卷 2754-2769页

作者： CHEN Wanxu XIE Youping YUAN Jintao zeng jie YANG Liyan GU Tianci LEI Fan Hubei Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China Key Laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region Ministry of Natural ResourcesChangsha 410118China Yunnan Key Laboratory of Plateau Geographic Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China

In recent decades,the spatio-temporal patterns of China’s croplands have been reshaped by disturbances from anthropogenic activities,with complex changes in the topographic characteristics of ***-climbing of croplands(SCCL)is an important issue that threatens sustainable agricultural *** providing land with prominent location advantages,SCCL weakens the water and fertilizer retention capacity for cropland,intensifies various geological disasters,and adversely affects the ecological environment and food yield of these *** is crucial to determine the spatio-temporal variation features and effects of SCCL in China to formulate more accurate cropland protection policies and to maintain food security;however,the current lack of relevant studies is detrimental for capturing trends in cropland resources and sustainable cropland *** this study,we constructed a multi-scale slope spectrum for cropland and total terrain to explore the spatial differences and trends of SCCL from a three-dimensional *** evaluated the natural and socioeconomic effects of SCCL in China from multiple *** indicate that the proportion of cropland with slopes below 2°,5°,and 6°in China decreased by 0.43%,0.47%,and 0.50%from 1980 to 2020,*** became apparent during 1980-1990 and 2010-2020,especially over the recent *** cropland climbing index(CCI)and upper limited slope change(ULSC)to measure the spatio-temporal pattern of SCCL were 0.99%and 1.17°,respectively,during *** the agricultural regional scale,the SCCL was also concentrated in 1980-1990 and 2010-2020,and it is more pronounced in the southern *** proportion of provinces and prefecture-level cities with high-intensity SCCL during 1980-2020 were 87.10%and 49.73%,*** was comparatively more pronounced and broader from 2010 to *** this period,17.84%of prefecture-level cities had no SCCL,and the average CCI for all prefecture-level citi

关键词： Croplands Slope spectrum Slope-climbing Three-dimensional perspective Multi-scale China

Reversible Mn^(2+)/Mn^(4+)double-electron redox in P3-type layer-structured sodium-ion cathode

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Journal of Energy Chemistry 2024年第2期89卷 79-88,I0004页

作者： jie zeng Jian Bao Ya Zhang Xun-Lu Li Cui Ma Rui-jie Luo Chong-Yu Du Xuan Xu Zhe Mei Zhe Qian Yong-Ning Zhou Department of Materials Science Fudan UniversityShanghai 200433China Shanghai Xuanyi New Energy Development Co. LtdShanghai 201800China Global Institute of Future Technology Shanghai Jiao Tong UniversityShanghai 200240China

The balance between cationic redox and oxygen redox in layer-structured cathode materials is an important issue for sodium batteries to obtain high energy density and considerable cycle *** redox can contribute extra capacity to increase energy density,but results in lattice instability and capacity fading caused by lattice oxygen gliding and oxygen *** this work,reversible Mn^(2+)/Mn^(4+)redox is realized in a P3-Na_(0.65)Li_(0.2)Co_(0.05)Mn_(0.75)O_(2)cathode material with high specific capacity and structure stability via Co *** contribution of oxygen redox is suppressed significantly by reversible Mn^(2+)/Mn^(4+)redox without sacrificing capacity,thus reducing lattice oxygen release and improving the structure *** X-ray techniques reveal that P3 phase is well maintained in a wide voltage window of 1.5-4.5 V ***^(+)/Na even at 10 C and after long-term *** is disclosed that charge compensation from Co/Mn-ions contributes to the voltage region below 4.2 V and O-ions contribute to the whole voltage *** synergistic contributions of Mn^(2+)/Mn^(4+),Co^(2+)/Co^(3+),and O^(2-)/(O_n)^(2-)redox in P3-Na_(0.65)Li_(0.2)Co_(0.05)Mn_(0.75)O_(2)lead to a high reversible capacity of 215.0 m A h g^(-1)at 0.1 C with considerable cycle *** strategy opens up new opportunities for the design of high capacity cathode materials for rechargeable batteries.

关键词： Sodium batteries Cathode materials Layered structure Co substitution

Prognostic relevance of ventricular arrhythmias in surgical patients with gastrointestinal tumors

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1787-1795页

作者： Jiao-jie Xue Su-Tian Hu Chong-Chong Wang Zhi-Chong Chen Shi-Yao Cheng Shu-Qi Yu Hua-Jing Peng Yi-Tao Zhang Wei-jie zeng Department of Cardiovascular Internal Medicine Sun Yat-sen University Sixth Affiliated HospitalGuangzhou 510655Guangdong ProvinceChina Department of Cardiovascular Internal Medicine The Fifth Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510700Guangdong ProvinceChina Department of Ultrasound Fuwai HospitalChinese Academy of Medical Sciences ShenzhenShenzhen 518052Guangdong ProvinceChina Department of Kidney Internal Medicine Sun Yat-sen University First Affiliated HospitalGuangzhou 510062Guangdong ProvinceChina

BACKGROUND Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular *** which,ventricular arrhythmia is a prevalent clinical *** suggests that ventricular arrhythmias may have predictive value in the prognosis of patients with gastrointestinal *** To explore the prognostic value of ventricular arrhythmias in patients with gastrointestinal tumors receiving *** We retrospectively analyzed data from 130 patients undergoing gastrointestinal tumor *** patients were evaluated by a 24-h ambulatory electrocardiogram(ECG)at the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to June ***,41 general healthy age-matched and sexmatched controls were *** were categorized into survival and non-survival *** primary endpoint was all-cause mortality,and secondary endpoints included major adverse cardiovascular events(MACEs).RESULTS Colorectal tumors comprised 90%of *** ambulatory ECG monitoring revealed that among the 130 patients with gastrointestinal tumors,100(76.92%)exhibited varying degrees of premature ventricular contractions(PVCs).Ten patients(7.69%)manifested non-sustained ventricular tachycardia(NSVT).The patients with gastrointestinal tumors exhibited higher PVCs compared to the healthy controls on both conventional ECG[27(21.3)vs 1(2.5),P=0.012]and 24-h ambulatory ECG[14(1.0,405)vs 1(0,6.5),P35/24 h to all-cause mortality,and NSVT was associated with ***,neither PVC burden nor NSVT independently predicted outcomes according to multivariate *** Patients with gastrointestinal tumors exhibited elevated ***>35/24 h and NSVT detected by 24-h ambulatory ECG were prognos

关键词： Ventricular arrhythmia Gastrointestinal tumor Major adverse cardiovascular events Prognostic Surgery

川西北地区中二叠统栖霞组白云岩形成机理——以车家坝剖面为例

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石油实验地质 2024年第2期46卷 288-298页

作者：曾杰董少峰西南石油大学地球科学与技术学院成都610500

以岩石学观察为基础,结合稳定同位素与团簇同位素分析,探讨了川西北地区中二叠统栖霞组白云岩形成机理。川西北车家坝剖面白云岩集中发育于栖霞组上段,可识别出基质白云石与白云石胶结物2种不同类型的白云石。基质白云岩呈灰白色,与灰... 详细信息

以岩石学观察为基础,结合稳定同位素与团簇同位素分析,探讨了川西北地区中二叠统栖霞组白云岩形成机理。川西北车家坝剖面白云岩集中发育于栖霞组上段,可识别出基质白云石与白云石胶结物2种不同类型的白云石。基质白云岩呈灰白色,与灰岩接触界线截然,呈指状交错接触;白云石胶结物呈乳白色,局限分布于溶蚀孔洞的边缘。镜下可进一步划分为3种类型基质白云石,即漂浮状细晶直面自形—半自形基质白云石(Md1)、细—中晶直面自形—半自形基质白云石(Md2)、中—粗晶它形曲面基质白云石(Md3),以及一种鞍形白云石胶结物(Sd)。Md1沿缝合线呈漂浮状分布于灰泥基质中,可能为浅埋藏环境下压溶作用的产物。Md2与Md3具有与宿主灰岩相似的δ^(13)C、δ^(18)O和^(87)Sr/^(86)Sr同位素特征,指示白云石化流体主要来源于二叠纪同期海水,而相对较高的成岩温度说明受二叠纪末大规模火山活动的影响显著。鞍形白云石及其后的方解石胶结物具有明显偏负的δ^(18)O值和放射性^(87)Sr/^(86)Sr值,说明它们形成于高温外源富放射性锶的白云石化流体中,可能为来自或穿过碎屑岩地层的深部热流体。川西北地区栖霞组白云岩的形成受原始沉积相与断裂活动的双重控制,热流体的注入使原始滩相地层发生白云石化作用,形成大量溶洞与晶间溶孔,对储层的改造起到了积极的建设性作用。

关键词：热流体稳定同位素团簇同位素白云岩栖霞组中二叠统川西北地区

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高阶网络统计指标综述

Synergistic effect of heterogeneous single atoms and clusters for improved catalytic performance

物理学报 2024年第12期73卷 60-77页

作者：刘波曾钰洁杨荣湄吕琳媛电子科技大学基础与前沿研究院成都 610054 电子科技大学长三角研究院(湖州) 湖州 313001 电子科技大学基础与前沿研究院成都 610054 中国科学技术大学网络空间安全学院合肥 230026 电子科技大学基础与前沿研究院成都 610054 电子科技大学长三角研究院(湖州) 湖州 313001

复杂网络是描述和理解现实世界中复杂系统的有力工具.近年来,为了更准确地描述复杂网络中的交互关系,或者从高阶视角分析成对交互作用网络,许多学者开始使用高阶网络进行建模,并在研究其动力学过程中发现了与成对交互作用网络不同的新现... 详细信息

复杂网络是描述和理解现实世界中复杂系统的有力工具.近年来,为了更准确地描述复杂网络中的交互关系,或者从高阶视角分析成对交互作用网络,许多学者开始使用高阶网络进行建模,并在研究其动力学过程中发现了与成对交互作用网络不同的新现象.然而,与成对交互作用网络相比,高阶网络的研究相对较少;而且,高阶网络结构相对复杂,基于结构的统计指标定义较为分散且形式不统一,这些都给描述高阶网络的拓扑结构特征带来了困难.鉴于此,本文综述了两种最常见的高阶网络——超图和单纯形网络——常用的统计指标及其物理意义.本文有助于加深对高阶网络的理解,促进对高阶网络结构特征的定量化研究,也有助于研究者在此基础上开发更多适用于高阶网络的统计指标.

关键词：高阶网络超图单纯形网络统计指标

来源：博看期刊评论

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中国科学技术大学学报 2024年第6期54卷 34-40,I0010页

作者： Long Liu Wenting Gao Yiling Ma Kainan Mei Wenlong Wu Hongliang Li Zhirong Zhang jie zeng Hefei National Research Center for Physical Sciences at the Microscale Key Laboratory of Strongly Coupled Quantum Matter Physics of Chinese Academy of SciencesKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesDepartment of Chemical PhysicsUniversity of Science and Technology of ChinaHefei 230026China School of Chemistry&Chemical Engineering Anhui University of TechnologyMa’anshan 243002China

Electrocatalytic water splitting provides an efficient method for the production of *** electrocatalytic water splitting,the oxygen evolution reaction(OER)involves a kinetically sluggish four-electron transfer process,which limits the efficiency of electrocatalytic water ***,it is urgent to develop highly active OER catalysts to accelerate reaction *** single atoms and clusters in one system is an innovative approach for developing efficient catalysts that can synergistically optimize the adsorption and configuration of intermediates and improve catalytic ***,research in this area is still ***,we constructed a heterogeneous single-atom cluster system by anchoring Ir single atoms and Co clusters on the surface of Ni(OH)_(2)*** single atoms and Co clusters synergistically improved the catalytic activity toward the ***,Co_(n)Ir_(1)/Ni(OH)_(2)required an overpotential of 255 mV at a current density of 10 mA·cm^(−2),which was 60 mV and 67 mV lower than those of Co_(n)/Ni(OH)_(2)and Ir1/Ni(OH)_(2),*** turnover frequency of Co_(n)Ir_(1)/Ni(OH)_(2)was 0.49 s^(−1),which was 4.9 times greater than that of Co_(n)/Ni(OH)_(2)at an overpotential of 300 mV.

关键词： single-atom cluster catalysts synergistic effect oxygen evolution reaction

Thiol Ligand-Modified Au for Highly Efficient Electroreduction of Nitrate to Ammonia

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Precision Chemistry 2024年第3期2卷 112-119页

作者： Yuheng Wu Xiangdong Kong Yechao Su Jiankang Zhao Yiling Ma Tongzheng Ji Di Wu Junyang Meng Yan Liu Zhigang Geng jie zeng Hefei National Research Center for Physical Sciences at the Microscale Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of SciencesKey Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education InstitutesDepartment of Chemical PhysicsUniversity of Science and Technology of ChinaHefeiAnhui 230026P.R.China School of Chemistry&Chemical Engineering Anhui University of TechnologyMa’anshanAnhui 243002P.R.China

Electroreduction of nitrate(NO_(3)-)to ammonia(NH_(3))is an environmentally friendly route for NH_(3)production,serving as an appealing alternative to the Haber-Bosch ***,various noble metal-based electrocatalysts have been reported for electroreduction of NO_(3)-.However,the application of pure metal electrocatalysts is still limited by unsatisfactory performance,owing to the weak adsorption of nitrogen-containing intermediates on the surface of pure metal *** this work,we report thiol ligand-modified Au nanoparticles as the effective electrocatalysts toward electroreduction of NO_(3)-.Specifically,three mercaptobenzoic acid(MBA)isomers,thiosalicylic acid(ortho-MBA),3-mercaptobenzoic acid(meta-MBA),and 4-mercaptobenzoic acid(para-MBA),were employed to modify the surface of the Au *** the NO_(3)-electroreduction,para-MBA modified Au(denoted as para-Au/C)displayed the highest catalytic activity among these Au-based ***-1.0 V versus reversible hydrogen electrode(vs RHE),para-Au/C exhibited a partial current density for NH_(3)of 472.2 mA cm^(-2),which was 1.7 times that of the pristine Au ***,the Faradaic efficiency(FE)for NH_(3)reached 98.7%at-1.0 V vs RHE for para-Au/*** modification of para-MBA significantly improved the intrinsic activity of the Au/C catalyst,thus accelerating the kinetics of NO_(3)-reduction and giving rise to a high NH_(3)yield rate of para-Au/C.

关键词： Ammonia synthesis NO_(3)-electroreduction Au nanoparticles thiol ligand modification electronic structure