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Role of micro-Ca/In alloying in tailoring the microstructural characteristics and discharge performance of dilute Mg-Bi-Sn-based alloys as anodes for Mg-air batteries

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Journal of Magnesium and Alloys 2024年第1期12卷 251-266页

作者： Fei-er Shangguan wei-li cheng Yu-hang Chen Ze-qin Cui Hui Yu Hong-xia Wang li-fei Wang Hang li Hua Hou School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are evaluated.The grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing alloy.Note that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing alloy.The electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical activity.Using In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca alloying.The micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly improved.The In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery.

关键词： Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors Discharge properties

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熔体过热和脉冲磁场协同处理对Mn_(5)Si_(3)增强Cu-35Zn-3Al合金显微组织、力学和耐磨性能的影响

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Transactions of Nonferrous Metals Society of China 2024年第3期34卷 918-934页

作者：李航牛冬涛张忠涛杨帆王红霞程伟丽太原理工大学材料科学与工程学院太原030024 金龙精密铜管有限公司重庆404100

研究熔体过热和脉冲磁场协同处理对Mn_(5)Si_(3)增强Cu-35Zn-3Al合金显微组织、力学和耐磨性能的影响。研究结果表明,协同处理促进了熔体中的溶质迁移以及Mn_(5)Si_(3)晶体生长的吸附动力学,抑制了六棱柱形貌Mn_(5)Si_(3)颗粒上孔洞的... 详细信息

研究熔体过热和脉冲磁场协同处理对Mn_(5)Si_(3)增强Cu-35Zn-3Al合金显微组织、力学和耐磨性能的影响。研究结果表明,协同处理促进了熔体中的溶质迁移以及Mn_(5)Si_(3)晶体生长的吸附动力学,抑制了六棱柱形貌Mn_(5)Si_(3)颗粒上孔洞的形成。协同处理后热锻态合金的抗拉强度和伸长率分别提高了9.0%和66.5%,这是由于拉伸变形过程中不含孔洞的Mn_(5)Si_(3)颗粒断裂强度提高,产生的应力集中减小,因此失效方式由脆性解理断裂转变为从基体中拔出,颗粒和基体间的载荷传递作用增强。在承受摩擦时,协同处理后合金的磨损亚表层中Mn_(5)Si_(3)颗粒不易发生剪切断裂,抑制了裂纹扩展和材料剥落,因而产生的剥层磨损减小,合金耐磨性显著提高。

关键词：复杂黄铜 Mn_(5)Si_(3)相脉冲磁场强化机理耐磨性

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数字化助推中国式教育现代化的核心要义及实践策略

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教学与管理 2024年第21期 27-31页

作者：宋述光姜付高李承伟曲阜师范大学教育学院山东曲阜273165 中国石油大学(华东)体育教学部山东青岛266580 曲阜师范大学体育学部山东曲阜273165

随着技术革命快速发展,数字化业已成为助推中国式教育现代化的重要手段。重塑现代教育的关系及要素,将对教育治理、教育功能、教育理念、教育形式等产生直接影响,形成全新的教育生态。然而,数字技术快速发展,也为中国式教育现代化带来... 详细信息

随着技术革命快速发展,数字化业已成为助推中国式教育现代化的重要手段。重塑现代教育的关系及要素,将对教育治理、教育功能、教育理念、教育形式等产生直接影响,形成全新的教育生态。然而,数字技术快速发展,也为中国式教育现代化带来潜在风险,教育体系过度数字化导致学生发展异化,影响学生社交、思维等全面发展,且存在隐私泄露风险。同时,数字鸿沟及教师数字素养的差异进一步加剧教育不公平,因此,享受数字技术为教育体系带来便利与高效的同时,需重新审视现代教育与数字逻辑的抵牾及对峙,打造中国式教育现代化新范式、规范数字教育制度、平衡数字教育资源、提升教师数字素养成为数字化背景下教育现代化发展的中国方案。

关键词：教育数字化教育强国中国式教育现代化教育高质量发展

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Challenges and strategies for ultrafast aqueous zinc-ion batteries

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Rare Metals 2021年第2期40卷 309-328页

作者： Qiao-Nan Zhu Zhen-Ya Wang Jia-wei Wang Xiao-Yu liu Dan Yang li-wei cheng Meng-Yao Tang Yu Qin Hua Wang School of Chemistry Beihang UniversityBeijing100191China College of Applied Science and Technology Beijing Union UniversityBeijing100012China Faculty of Science Engineering and TechnologySwinburne University of TechnologyHawthorn3122VICAustralia Institute of Chemistry Henan Academy of SciencesZhengzhou450002China

With the rising demand for fast-charging technology in electric vehicles and portable devices,significant efforts have been devoted to the development of the highrate batteries.Among numerous candidates,rechargeable aqueous zinc-ion batteries(ZlBs)are a promising option due to its high theoretical capacity,low redox potential of zinc metal anode and inherent high ionic conductivity of aqueous electrolyte.As the strong electrostatic interaction between Zn^(2+)and host generally leads to sluggish electrode kinetics,many strategies have been proposed to enhance fast(dis)charging performance.Herein,we review the state-of-the-art ultrafast aqueous ZIBs and focus on the rational electrode-designing strategies,such as crystal structure engineering,nanostructuring and morphology controlling,conductive materials introducing and organic molecule designing.Recent research directions and future perspectives are also proposed in this review.

关键词： Aqueous zinc-ion battery Cathode materials Energy density Energy storage Rate capacity Ultrafast

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Molecular simulation study on the evolution process of hydrate residual structures into hydrate

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Chinese Journal of Chemical Engineering 2024年第5期69卷 79-91页

作者： liwei cheng Yunfei li Jinlong Cui Huibo Qin Fulong Ning Bei liu Guangjin Chen Faculty of Engineering China University of GeosciencesWuhan 430074China State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China College of Science Nanchang Institute of TechnologyNanchang 330099China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China National Center for International Research on Deep Earth Drilling and Resource Development China University of Geosciences(Wuhan)Wuhan 430074China

The clathrate hydrate memory effect is a fascinating phenomenon with potential applications in carbon capture,utilization and storage(CCUS),gas separation,and gas storage as it can accelerate the secondary formation of clathrate hydrate.However,the underlying mechanism of this effect remains unclear.To gain a better understanding of the mechanism,we conducted molecular dynamic simulations to simulate the initial formation and reformation processes of methane hydrate.In this work,we showed the evolution process of hydrate residual structures into hydrate cages.The simulation results indicate that the residual structures are closely related to the existence of hydrate memory effect,and the higher the contribution of hydrate dissociated water to the hydrate nucleation process,the faster the hydrate nucleation.After hydrate dissociation,the locally ordered structures still exist after hydrate dissociation and can promote the formation of cluster structures,thus accelerating hydrate nucleation.Additionally,the nucleation process of hydrate and the formation process of clusters are inseparable.The size of clusters composed of cup-cage structures is critical for hydrate nucleation.The residence time at high temperature after hydrate decomposition will affect the strength of the hydrate memory effect.Our simulation results provide microscopic insights into the occurrence of the hydrate memory effect and shed light on the hydrate reformation process at the molecular scale.

关键词： Memory effect Molecular simulation Hydrate reformation Residual structures

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秸秆还田和水旱轮作模式对稻季土壤温室气体排放的影响

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植物营养与肥料学报 2024年第2期30卷 268-278页

作者：邓姣李心雨朱杰杨伟李成伟蒋梦蝶朱波聂江文刘章勇长江大学农学院主要粮食作物产业化湖北省协同创新中心湖北荆州434200 湖北省襄阳市农业科学院湖北襄阳441100

【目的】探究不同水旱轮作模式下,冬季作物秸秆还田对后茬水稻季作物产量和温室气体排放的影响,为长江中游稻田选择适宜的秸秆还田方式和农业可持续生产提供科学依据。【方法】田间试验在湖北荆州进行,设置水稻–小麦(稻麦)、水稻–油菜... 详细信息

【目的】探究不同水旱轮作模式下,冬季作物秸秆还田对后茬水稻季作物产量和温室气体排放的影响,为长江中游稻田选择适宜的秸秆还田方式和农业可持续生产提供科学依据。【方法】田间试验在湖北荆州进行,设置水稻–小麦(稻麦)、水稻–油菜(稻油)和水稻–紫云英(稻肥)3种水旱轮作模式,每个模式下设置冬季作物收获后秸秆还田和不还田处理。在秸秆还田后的水稻季,采用静态暗箱—气相色谱法连续监测稻田中甲烷(CH_(4))和氧化亚氮(N_(2)O)排放量,在水稻分蘖期、抽穗期、成熟期采集0—5、5—10、10—20 cm土层样品,测定微生物量碳(MBC)、可溶性有机碳(DOC)、铵态氮(NH_(4)^(+)-N)和硝态氮(NO_(3)^(-)-N)含量,收获期测定水稻产量。【结果】秸秆还田和不同轮作模式对后茬水稻产量均无显著影响。与稻肥轮作相比,在秸秆还田条件下稻油和稻麦轮作水稻季土壤CH_(4)和N_(2)O排放分别高出44%~58%和17%~30%,在秸秆不还田条件下则分别高出58%~72%和15%~22%。与秸秆不还田相比,秸秆还田条件下3种轮作模式平均CH_(4)和N_(2)O排放分别增加26%~39%和20%~29%。秸秆还田条件下,稻油和稻麦轮作稻季土壤全球增温潜势(GWP)和温室气体排放强度(GHGI)分别比稻肥轮作高出14%~19%和12%~19%,秸秆不还田条件下分别高出18%~23%和15%~24%。与秸秆不还田相比,秸秆还田条件下3种轮作模式稻季土壤平均GWP和GHGI高出31%和32%,同时土壤硝态氮、微生物量碳和可溶性有机碳含量均显著提高。此外,稻麦轮作土壤微生物量碳和可溶性有机碳含量显著高于稻肥、稻油轮作。相关性分析表明,秸秆还田条件下,CH_(4)和N_(2)O排放与NO_(3)^(-)-N呈极显著正相关(P<0.01),而秸秆不还田条件下CH_(4)排放与NO_(3)^(-)-N呈极显著正相关(P<0.01),N_(2)O排放与NH_(4)^(+)-N呈极显著正相关(P<0.01)。【结论】水稻季土壤CH_(4)和N_(2)O的排放与土壤可利用性碳氮浓度的升高密切相关。前茬作物秸秆还田导致水稻季温室气体排放显著增加,与稻麦、稻油轮作相比,水稻–紫云英轮作稻季土壤的温室气体排放量最低,是较为生态环境友好型的种植制度。

关键词：轮作模式秸秆还田增温潜势排放强度土壤可溶性有机碳微生物量碳有效氮

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Tissue distribution of deoxynivalenol in piglets following intravenous administration

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Journal of Integrative Agriculture 2015年第10期14卷 2058-2064页

作者： DENG Xian-bai DIN Huan-zhong HUANG Xian-hui MA Yong-jiang FAN Xiao-long YAN Hai-kuo LU Pei-cheng li wei-cheng ZENG Zhen-ling College of Veterinary Medicine South China Agricultural University

Contamination of deoxynivalenol（DON） in grains is common worldwide and pigs are particularly susceptible to this mycotoxin. The distribution of DON in porcine tissues following intravenous administration was investigated in this study. Fifteen pigs were randomly divided into three groups. Animals in groups A and B were administrated with DON at the dose of 250 and 750 μg kg–1 body weight, respectively, while group C served as blank control. Plasma, bile and 27 tissues were collected at 30 min post-administration. DON concentrations in all samples were tested using high-performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）. To observe the distribution of DON in tissues, these samples were further subjected to the immunohistochemical analyses. Totally, the bile and 13 tissues were sampled for DON-based detection, including kidney, mesenteric lymph nodes, muscle, stomach, jejunum, colon, plasma, spleen, rectum, cecum, liver, ileum, and duodenum. No significant difference was observed for the concentrations of DON in duodenum, ileum and liver samples between groups A and B; while the DON concentrations in cecum and rectum of group B were significantly higher（P-value 〈0.05） than those in group A. In addition, the DON concentrations in stomach, jejunum, colon, mesenteric lymph nodes, muscle, kidney, spleen, bile, and plasma of group B were remarkably higher than those of group A（P-value〈0.01）. Levels of DON in other 14 tissues including medulla oblongata, midbrain, diencephalon, pons, tip and tongue body, tongue, soft palate, tonsils, pharyngeal mucosa, oral buccal mucosa, thymus, thyroid, esophagus and adrenal gland were all below the limit of detection. The results of immunohistochemistry showed that 11 tissue samples（medullaoblongata, tonsil, adrenal medulla, thyroid gland, thyroid, stomach, duodenum, jejunum, kidney, spleen, and mesenteric lymph nodes） were positive and DON was mainly distributed around blood vessels in these tissues. Therefore, we believed that concentrations of DON in tissues dif

关键词： deoxynivalenol,tissue distribution,immunohistochemical staining,HPLC-MS/MS,swine

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Unveiling the twinning and dynamic recrystallization behavior and the resultant texture evolution in the extruded Mg-Bi binary alloys during hot compression

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Journal of Materials Science & Technology 2022年第10期105卷 274-285页

作者： Yu-qin Zhang wei-li cheng Hui Yu Hong-xia Wang Xiao-feng Niu li-fei Wang Hang li School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China

The twinning behavior, dynamic recrystallization(DRX) mechanism and the resultant texture evolution of the extruded Mg-xBi(x=0.5 wt.%, 2.0 wt.%) alloys were systematically investigated during hot compression at the strain rate of 10 s^(-1) and temperature of 200℃. The results indicate that the types and intensities of the texture are greatly dependent on the twining behavior and DRX mechanism. At the initial stage, the evolution of texture is mainly domination by the formation and variation of {1012} extension twins, which is benefcial to the compression direction(CD)-tilted basal texture. With an increase in the strain, the texture evolution is more greatly regulated by the DRX mechanism. Besides, the pyramidal slip and basal slip are activated during the compression process, resulting in the Schmid factors(SF) of pyramidal slip remain at ~0.4 and the average SFs for basal slip increase from 0.2 to0.34 as the strain increase. These fndings provide a new insight into controlling the texture of wrought Mg-Bi-based alloys during hot deformation processing.

关键词： Wrought Mg-Bi alloys Hot deformation Twinning Dynamic recrystallization Dislocation slip Texture

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Effect of droplet characteristics on liquid-phase distribution in spray zone of internal mixing air-mist nozzle

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China Foundry 2024年第2期21卷 185-196页

作者： wei-li Wu Chang-gui cheng Yang li Shi-fa wei De-li Chen The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081China Technology Center Fushun Special Steel Co.Ltd.Fushun 113001LiaoningChina

In continuous casting production,droplet characteristics are important parameters for evaluating the nozzle atomization quality,and have a significant impact on the secondary cooling effect and the slab quality.In order to study the behavior of atomized droplets after reaching the slab surface and to optimize the spray cooling effect,the influence of droplet diameter and droplet velocity on the migration behavior of droplets in the secondary cooling zone was analyzed by FLUENT software.Results show that the droplets in the spray zone and on the slab surface are mainly concentrated in the center,thus,the liquid volume fraction in the center is higher than that of either side.As the droplet diameter increases,the region of high liquid volume fraction on the slab surface becomes wider,and the liquid phase distribution in the slab width direction becomes uneven.Although increasing the droplet velocity at the nozzle exit has little effect on droplet diffusion in the spray zone,the distribution becomes more uneven due to more liquid reaches the slab surface per unit time.A prediction formula of the maximum water flow rate on the slab surface for specific droplet characteristics was proposed based on dimensionless analysis and validated by simulated data.A nozzle spacing of 210 mm was recommended under the working conditions in this study,which ensures effective coverage of the spray water over the slab surface and enhances the distribution uniformity of water flow rate in the transverse direction.

关键词： continuous casting secondary cooling zone internal mixing air-mist nozzle droplet characteristics liquid phase distribution water flow rate

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Classification of complete 3-dimensional self-shrinkers in the Euclidean space R^(4)

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Science China Mathematics 2024年第4期67卷 873-882页

作者： Qing-Ming cheng Zhi li Guoxin wei Department of Applied Mathematics Faculty of ScienceFukuoka UniversityFukuoka 814-0180Japan College of Mathematics and Information Science Henan Normal UniversityXinxiang 453007China School of Mathematical Sciences South China Normal UniversityGuangzhou 510631China

In this paper,we completely classify 3-dimensional complete self-shrinkers with the constant norm S of the second fundamental form and the constant f3in the Euclidean space R^(4),where hij’s are components of the sec... 详细信息

关键词： mean curvature ow self-shrinker the generalized maximum principle

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