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Homogeneous distributed natural pyrite-derived composite induced by modified graphite as high-performance lithium-ion batteries anode

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International Journal of Minerals,Metallurgy and Materials 2023年第7期30卷 1353-1362页

作者： Juan Yu Yinbo Wei Bicheng Meng Jiaxin peng Kai Yang Tianxing Chen Naixing Yang xiuyun Chuan School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China School of Earth and Space Sciences Peking UniversityBeijing 100871China Shaanxi Key Laboratory of Nano-Materials and Technology School of Mechanical and Electrical EngineeringXi’an University of Architecture and TechnologyXi’an 710055China School of Resources Engineering Xi’an University of Architecture TechnologyXi’an 710055China

Natural minerals-based energy materials have attracted enormous attention because of the advantages of good materials consistency,high production,environmental friendliness,and low cost.The uniform distribution of grains can effectively inhibit the aggregation of active materials,improving lithium storage performance.In this work,natural graphite is modified by polyvinylpyrrolidone to obtain modified graphite with reduced size and better dispersion.Natural pyrite composite polyvinylpyrrolidone-modified graphite(pyrite/PG)material with uniform particle distribution is obtained by the ball milling process.The subsequent calcination process converts pyrite/PG into Fe_(1-x)Scompounded with polyvinylpyrrolidone-modified graphite(Fe_(1-x)S/PG).The homogeneous grain distributions of active material can facilitate the faster transfer of electrons and promote the efficient utilization of active materials.The as-prepared Fe_(1-x)S/PG electrode exhibits a remarkably reversible specific capacity of 613.0 mAh·g^(-1)at 0.2 A·g^(-1)after 80 cycles and an excellent rate capability of 523.0 mAh·g^(-1)at 5 A·g^(-1).Even at a higher current density of 10 A·g^(-1),it can deliver a specific capacity of 348.0 mAh·g^(-1).Moreover,the dominant pseudocapacitance in redox reactions accounts for the impressive rate and cycling stability.This work provides a low-cost and facile method to fabricate natural mineral-based anode materials and apprise readers about the impact of uniform particle distribution on lithium storage performance.

关键词： natural pyrite modified graphite anode lithium-ion batteries homogeneous grain distributions

TWO-VALUED RESPONSE TECHNIQUE OF POLYCHOTOMOUS SENSITIVE QUESTION

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Journal of Systems Science & Complexity 2011年第6期24卷 1193-1203页

作者： xiuyun peng Zaizai YAN Science College Inner Mongolia University of Technology Hohhot 010051 China Management College Inner Mongolia University of Technology Hohhot 010051 China

当收集敏感信息时，使随机化的反应(RR ) 技术是一个有效调查方法。这份报纸与 polychotomous 为调查采样建议一个新非使随机化的反应模型敏感问题：两价的反应技术。没有代替并且与代替图案，敏感属性和它的评估者变化的比例在简单随... 详细信息

当收集敏感信息时，使随机化的反应(RR ) 技术是一个有效调查方法。这份报纸与 polychotomous 为调查采样建议一个新非使随机化的反应模型敏感问题：两价的反应技术。没有代替并且与代替图案，敏感属性和它的评估者变化的比例在简单随机的采样下面被估计。在效率和隐私的保护之间的关系被讨论。结果显示效率在与在新建议模型的隐私的保护的冲突，它在 RR 技术与那一样，但是新技术比 RR 技术在社会学的实践方面有更好的特征，因为它具有低费用，节省的时间并且容易被操作。

关键词：技术社会学敏感信息二值简单随机抽样随机响应隐私保护响应模型抽样调查

Effects of cerium and tungsten addition on acid-base properties of spindle-likeα-Fe_(2)O_(3)in low-temperature SCR of NO_(x)with NH_(3)

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Journal of Rare Earths 2022年第11期40卷 1734-1742,I0003页

作者： Jun Ni Xuanbei peng Linlin Yang Kai Zhang Yangyu Zhang Yanliang Zhou xiuyun Wang Chak-tong Au Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary sources.In the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)methods.The scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or W.The results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate basicity.On the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid sites.The synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low temperatures.The study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.

关键词： NH_(3)-SCR Fe_(2)O_(3) NO_(x)removal Acidity/basicity properties Morphology structure Rare earths

以视物晃动首诊于眼科的29例振动幻视患者临床特征分析

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眼科 2024年第1期33卷 9-14页

作者：崔世磊彭静婷孔秀云吴京王佳伟江汉秋首都医科大学附属北京同仁医院神经内科北京100730

目的回顾性分析视物晃动患者的临床特征、眼动异常类型以及相关病因、治疗预后。设计回顾性病例系列。研究对象2019年1月至2023年1月首诊于北京同仁医院眼科,而后转诊至神经内科的振动幻视患者29例。方法回顾患者的临床病历资料,包括视... 详细信息

目的回顾性分析视物晃动患者的临床特征、眼动异常类型以及相关病因、治疗预后。设计回顾性病例系列。研究对象2019年1月至2023年1月首诊于北京同仁医院眼科,而后转诊至神经内科的振动幻视患者29例。方法回顾患者的临床病历资料,包括视物晃动特征、视频眼震图的特征、颅脑MRI、病因诊断、治疗方案及转归等。主要指标视物晃动特征、视频眼震图、颅脑MRI。结果29例患者均表现为视物晃动及视觉相关性头晕,27例(93.1%)为双眼症状,其中18例为垂直性视物晃动,8例为水平性视物晃动,1例为跷跷板性(垂直和扭转混合型)视物晃动;2例(6.9%)为单眼症状,分别为扭转性、水平性视物晃动。27例(93.1%)为持续性症状,2例(6.9%)为发作性症状。视频眼震图显示,视物晃动方向、眼别与异常眼动一致,23例(79.3%)为眼震,其中下跳性眼震17例,周期性交替性眼震、获得性摆动性眼震和摆动性跷跷板眼震分别为3例、2例和1例;3例为(10.3%)扫视侵入;2例(6.9%)为前庭功能低下;1例(3.4%)为上斜肌颤搐。所有患者均接受至少一次颅脑MRI检查,21例(87.5%)有小脑扁桃体或视神经等部位的阳性异常改变,14例(48.3%)患者经手术减压或加巴喷丁、巴氯芬或氯硝西泮等治疗后好转。结论振动幻视患者以双眼垂直性、水平性视物晃动最为常见。病因多样,其特征与异常眼动类型相关,其中获得性眼震最为常见。

关键词：视物晃动振动幻视眼震眼震样异常眼动

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防静电环氧地坪涂料导电矿物材料

非金属矿 2024年第3期47卷 102-107页

作者：传秀云唐泱彭洪均李严虞晟阳朱晨硕刘爽李建海北京大学地球与空间科学学院造山带与地壳演化教育部重点实验室北京100871 大厂金隅涂料有限责任公司河北廊坊065300 北京建筑材料科学研究总院有限公司固废资源化利用与节能建材国家重点实验室北京100041

静电产生的电磁波危害工作生活,因此需要性能良好的静电防护材料。本研究综合分析了静电防护涂料中导电材料的特点和防静电机理。以防静电环氧地坪涂料为例,分析静电防护材料中的导电矿物材料,重点分析了导电金属抗静电涂料、浅色抗静... 详细信息

静电产生的电磁波危害工作生活,因此需要性能良好的静电防护材料。本研究综合分析了静电防护涂料中导电材料的特点和防静电机理。以防静电环氧地坪涂料为例,分析静电防护材料中的导电矿物材料,重点分析了导电金属抗静电涂料、浅色抗静电涂料、碳系抗静电涂料中导电矿物材料。以碳系抗静电涂料为主,分析了决定防静电性能的导电材料的成分、结构和性能。在此基础上,探讨抗静电地坪涂料导电矿物材料的发展趋势,探索能够防护静电的高性能抗静电地坪涂料。与传统导电材料相比,碳石墨矿物材料具有明显优势。采用石墨矿物为原料合成的石墨烯碳添加少量就能大幅提高环氧树脂的电导率,获得优异的防静电效果。深入研究导电矿物微观结构特点,在分子原子层次上进行纳米结构组装,有可能开发出高性价比的抗静电涂料,提高电子仪表、医药等行业生产生活洁净场所的防静电水平。

关键词：防静电环氧地坪涂料导电石墨石墨烯

Boosting Efficient Ammonia Synthesis over Atomically Dispersed Co-Based Catalyst via the Modulation of Geometric and Electronic Structures

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CCS Chemistry 2022年第5期4卷 1758-1769页

作者： Yanliang Zhou Congying Wang Xuanbei peng Tianhua Zhang xiuyun Wang Yafei Jiang Haifeng Qi Lirong Zheng Jianxin Lin Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhouFujian 350002 Department of Chemistry Southern University of Science and TechnologyShenzhen 518055 Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049

Ammonia(NH_(3))synthesis at mild conditions is of great significance,while the significant bottleneck of this process is the activation of N_(2) to realize the desired NH_(3) synthesis performance,which requires deep insight and rational design of active sites at the atomic level.Here,were synthesized atomically dispersed Co-based catalysts with different Co-N coordination numbers(CNs)to explore the coordination-sensitive NH_(3) synthesis reaction for the first time.Our studies showed that Co-based catalysts increased the NH_(3) synthesis rate gradually with a decrease in CN.The Co-N_(2) catalyst exhibited the highest NH_(3) synthesis rate of 85.3 mmol gCo^(−1) h^(−1) at 300℃ and 1 MPa,which outperformed most of the previously reported Co-based catalysts.Various characterizations and theoretical calculations demonstrated that atomically dispersed Co catalyst with low CN could generate more unoccupied Co 3d charges and tetrahedral cobalt(Ⅱ)sites.The unoccupied Co 3d charge,in turn,promoted the electron donation from the Co active center to the antibonding π-orbital(π*)of N_(2) and expedites N_(2) hydrogenation.Furthermore,the Co-N_(2) catalyst with more tetrahedral cobalt(II)sites could effectively facilitate the desorption of N-containing intermediate species(such as*NH_(3) and*N_(2)H_(4))to obtain a high NH_(3) synthesis rate.

关键词： ammonia synthesis coordination number electron transfer geometric structure intermediate species

簇-金属氧化物助剂电子相互作用调控的Ru原子簇催化剂用于温和条件下合成氨反应

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Chinese Journal of Catalysis 2024年第5期60卷 209-218页

作者：张天华胡海慧李嘉欣高迎龙李玲玲张明远彭渲北周岩良倪军林炳裕林建新朱兵吴冬霜张林杰韩丽丽郑黎荣王秀云江莉龙福州大学化肥催化剂国家工程研究中心福建福州350002 福州大学化学学院福建福州350002 南洋理工大学材料科学与工程学院新加坡639798 中国科学院福建物质结构研究所结构化学国家重点实验室福建福州350002 中国科学院高能物理研究所北京100049

氨是重要的化肥原料,也是颇具潜力的氢能源载体,对于可再生能源的储存、运输和终端利用至关重要.然而,传统Haber-Bosch工艺合成氨的反应条件苛刻,需要高温高压条件,并消耗大量化石能源及排放大量二氧化碳.可再生能源电解水制氢耦合温和... 详细信息

氨是重要的化肥原料,也是颇具潜力的氢能源载体,对于可再生能源的储存、运输和终端利用至关重要.然而,传统Haber-Bosch工艺合成氨的反应条件苛刻,需要高温高压条件,并消耗大量化石能源及排放大量二氧化碳.可再生能源电解水制氢耦合温和合成氨新技术(eHB),不仅能实现可再生能源电力的“消纳和调峰”,而且可进行低成本、跨地域长距离存储运输,并可将“绿氨”与氢能产业相结合.然而,现有的高温高压合成氨催化剂与eHB工艺相不匹配,因此,迫切需要开发温和条件下高效合成氨催化剂技术,以实现可再生能源电力电解制氢体系和合成氨技术互补融合.目前,虽然助剂对于Ru基纳米簇(≥1 nm)合成氨催化剂的影响规律已得到了广泛研究,但它们对于Ru原子簇催化剂的作用机制尚不清楚,需要进一步揭示.本文考察了Ba及Ce助剂对Ru原子簇催化剂的影响规律,并分析了其作用机制.首先,通过简单的浸渍法将Ba和/或Ce物种掺杂到Ru原子簇催化剂(2 wt%Ru ACCs),制得Ba/Ce/2 wt%Ru ACCs催化剂;然后,通过一系列实验考察了这些催化剂的合成氨性能,并利用多种表征手段对其进行了深入分析.合成氨性能测试结果表明,添加Ba和Ce助剂后,2 wt%Ru ACCs催化剂的合成氨速率明显提高,在400 o C和1 MPa下,Ba/Ce/2 wt%Ru ACCs催化剂的合成氨反应速率达到56.2 mmolNH_(3) gcat^(-1) h^(-1),是2 wt%Ru ACCs的7.5倍,且催化剂表现出较好的稳定性,在稳定运行140 h后活性未见明显降低.球差校正电子显微镜和X射线吸收精细结构谱结果表明,负载Ba和/或Ce后,Ru以Ru3原子簇形式存在.X射线吸收近边结构谱和X射线光电子能谱结果表明,Ru与Ba及Ce物种之间存在较强的簇-金属氧化物助剂电子相互作用,可促进电子转移到Ru物种,形成富电子状态的Ru,进而促使电子转移到N2的p*反键轨道,提高温和条件下合成氨反应速率.利用25%N2+75%D2气氛下的原位红外光谱研究催化剂的合成氨反应机理,结果表明,在Ba/Ce/2 wt%Ru ACCs催化剂表面同时检测到N2D2物种和N2Dx物种的振动吸收峰,说明添加Ba和/或Ce物种没有改变Ru原子簇催化剂活化N2的方式,N2仍是通过加氢的路径合成氨.综上,本文考察了助剂对Ru原子簇的影响规律,揭示了其作用机制,为设计高效的温和条件合成氨催化剂提供参考.

关键词：原子簇助剂 N2活化合成氨电子相互作用

Challenges and prospects in artificial nitrogen cycle for energy decarbonization

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National Science Open 2023年第2期2卷 89-92页

作者： Huihuang Fang Yanliang Zhou Xiaobo peng Yu Luo xiuyun Wang Shijing Liang Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China Qingyuan Innovation Laboratory Quanzhou 362801China

Fossil fuels still dominate global energy structure in our modern society,and have led to massive CO_(2) emissions.Recently,ammonia has been regarded as a clean energy carrier toward diminishing or even eliminating the CO_(2) emissions and has received significant attention.The ammonia can be synthesized from atmospheric dinitrogen and green hydrogen from water electrolysis by renewable energies,and converted back into dinitrogen and water for energy release,as shown in Figure 1.Benefited from the matured ammonia manufacture and transportation throughout the world for over one century,the already existing high-capacity infrastructure helps efficient storage and redistribution of ammonia with lowest economic cost.However,although considerable progress has been made in this artificial nitrogen cycle,there are still many challenges in developing highly-efficient routes and catalysts.Herein,we evaluate the current catalytic routes of ammonia synthesis(including thermocatalytic synthesis,electrocatalytic synthesis and photocatalytic synthesis)and ammonia utilization(involving ammonia decomposition,direct ammonia fuel cells and ammonia combustion).We also discuss the key issue in each process,and anticipate that our viewpoints and opinions could facilitate the developments of artificial nitrogen cycle and energy decarbonization.

关键词： ammonia synthesis cycle

Anti-oxidative effect of ribonuclease inhibitor by site-directed mutagenesis and expression in Pichia pastoris

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Frontiers in Biology 2006年第2期1卷 99-103页

作者： Wu Yu Cui xiuyun Wang Jihong Zhao peng Xu Yuefei Zhao Baochang College of Live Sciences Liaoning Normal UniversityDalian 116029China Department of Biochemistry and Molecular Biology Dalian Medical UniversityDalian 116027China

Human placental ribonuclease inhibitor(hRI)is an acidic protein of Mr∼50kDa with unusually high contents of leucine and cysteine residues.It is a cytosolic protein that protects cells from the adventitious invasion of pancreatic-type ribonuclease.hRI has 32 cysteine residues,and the oxidative formation of disulfide bonds from those cysteine residues is a rapid cooperative process that inactivates hRI.The most proximal cysteine residues in native hRI are two pairs that are adjacent in sequence.In the present aork,two molecules of alanine substituting for Cys328 and Cys329 were performed by site-directed mutagenesis.The site-mutated RI cDNA was constructed into plasmid pPIC9K and then transformed Pichia pastoris GS115 by electroporation.After colony screening,the bacterium was cultured and the product was purified with affinity chromatography.The affinity of the recombinant human RI with double site mutation was examined for RNase A and its anti-oxidative effect.Results indicated that there were not many changes in the affinity for RNase A detected when compared with the wild type of RI.But the capacity of anti-oxidative effect increased by 7~9 times.The enhancement in anti-oxidative effect might be attributed to preventing the formation of disulfide bond between Cys328 and Cys329 and the three dimensional structure of RI was thereby maintained.

关键词： ribonuclease inhibitor site-directed mutagenesis cysteine Pichia pastoris reactive oxygen species