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National Science Review 2024年第4期11卷 195-205页

作者： yanhua wan Changyao wang Xingmiao Zhang Yang Yin Mengmeng Liu Bing Ma Linlin Duan Yuzhu Ma Wei Zhang Changlin Zheng Dongliang Chao Fei wang Yongyao Xia Wei Li Department of Chemistry Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of Polymers College of Chemistry and Materials ScienceFudan University State Key Laboratory of Surface Physics and Department of Physics Fudan University

Due to their uncontrollable assembly and crystallization process,the synthesis of mesoporous metal oxide single crystals remains a formidable challenge.Herein,we report the synthesis of single-crystal-like mesoporous Li2TiSiO5by using soft micelles as templates.The key lies in the atomic-scale self-assembly and step-crystallization processes,which ensure the formation of single-crystal-like mesoporous Li2TiSiO5microparticles via an oriented attachment growth mechanism under the confinement of an in-situ formed carbon matrix.The mesoporous Li2TiSiO5anode achieves a superior rate capability(148 mAh g-1at5.0 A g-1) and outstanding long-term cycling stability(138 mAh g-1after 3000 cycles at 2.0 A g-1) for lithium storage as a result of the ultrafast Li+diffusion caused by penetrating mesochannels and nanosized crystal frameworks（5-10 nm）.In comparison,bulk Li2TiSiO5exhibits poor rate capability and cycle performance due to micron-scale diffusion lengths.This method is very simple and reproducible,heralding a new way of designing and synthesizing mesoporous single crystals with controllable frameworks and chemical functionalities.

关键词： mesoporous materials micelles single-crystal-like Li2TiSiO5 lithium-ion batteries

Recent advances in hard carbon anodes with high initial Coulombic efficiency for sodium-ion batteries

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Nano Materials Science 2023年第2期5卷 189-201页

作者： yanhua wan Yao Liu Dongliang Chao Wei Li Dongyuan Zhao Department of Chemistry Laboratory of Advanced MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsState Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai200433China

Initial Coulombic efficiency(ICE)has been widely adopted in battery research as a quantifiable indicator for the lifespan,energy density and rate performance of batteries.Hard carbon materials have been accepted as a promising anode family for sodium-ion batteries(SIBs)owing to their outstanding performance.However,the booming application of hard carbon anodes has been significantly slowed by the low ICE,leading to a reduced energy density at the cell level.This offers a challenge to develop high ICE hard carbon anodes to meet the applications of high-performance SIBs.Here,we discuss the definition and factors of ICE and describe several typical strategies to improve the ICE of hard carbon anodes.The strategies for boosting the ICE of such anodes are also systematically categorized into several aspects including structure design,surface engineering,electrolyte optimization and pre-sodiation.The key challenges and perspectives in the development of high ICE hard carbon anodes are also outlined.

关键词： Sodium-ion battery Hard carbon Initial Coulombic efficiency Interface engineering Anode

Pre-sodiation strategy for superior sodium storage batteries

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Chinese Journal of Chemical Engineering 2021年第11期34卷 261-268页

作者： Yongkai Xu Haozheng Sun Cunshuang Ma Jingjing Gai yanhua wan Weihua Chen Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China

The irreversible consumption of sodium in the initial several cycles greatly led to the attenuation of capacity,which caused the low initial coulombic efficiency(ICE)and obvious poor cycle stability.Presodiation can effectively improve the electrochemical performance by compensating the capacity loss in the initial cycle.Here,carbon-coated sodium-pretreated iron disulfide(NaFeS_(2)@C)has been synthesized through conventional chemical method and used in sodium metal battery as a cathode material.The calculated density of states(DOS)of NaFeS2@C is higher,which implies enhanced electron mobility and improved cycle reversibility.Because of the highly reversible conversion reaction and the compensation of irreversible capacity loss during the initial cycle,the Na/NaFeS_(2)@C battery achieves ultrahigh initial coulombic efficiency(96.7%)and remarkable capacity(751 mA·h·g^(-1) at 0.1 A·g^(-1)).In addition,highly reversible electrochemical reactions and ultra-thin NaF-rich solid electrolyte interphase(SEI)also benefit for the electrochemical performance,even at high current density of 100 A·g^(-1),it still exhibits a reversible capacity of 136 mA·h·g^(-1),and 343 mA·h·g^(-1) after 2500 cycles at 5.0 A·g^(-1).This work aims to bring up new insights to improve the ICE and stability of sodium metal batteries.

关键词： Pre-sodiation Solid electrolyte interphase Initial coulombic efficiency Sodium metal batteries Interface Electrochemistry

Achieving long-cycling sodium-ion full cells in ether-based electrolyte with vinylene carbonate additive

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Journal of Energy Chemistry 2021年第6期30卷 650-655,I0016页

作者： Juan Shi Lina Ding yanhua wan Liwei Mi Linjie Chen Dan Yang Yuxiong Hu Weihua Chen Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001HenanChina Henan Key Laboratory of Functional Salt Materials Center of Advanced Materials ResearchZhongyuan University of TechnologyZhengzhou 450007HenanChina College of Pharmacy Zhengzhou UniversityZhengzhou 450001HenanChina

Application of sodium-ion batteries is suppressed due to the lack of appropriate electrolytes matching cathode and anode simultaneously.Ether-based electrolytes,preference of anode materials,cannot match with high-potential cathodes failing to apply in full cells.Herein,vinylene carbonate(VC)as an additive into NaCF_(3) SO_(3)-Diglyme(DGM)could make sodium-ion full cells applicable without preactivation of cathode and anode.The assembled FeS@C||Na3 V2(PO_(4))_(3)@C full cell with this electrolyte exhibits long term cycling stability and high capacity retention.The deduced reason is additive VC,whose HOMO level value is close to that of DGM,not only change the solvent sheath structure of Na^(+),but also is synergistically oxidized with DGM to form integrity and consecutive cathode electrolyte interphase on Na3 V2(PO_(4))_(3)@C cathode,which could effectively improve the oxidative stability of electrolyte and prevent the electrolyte decomposition.This work displays a new way to optimize the sodium-ion full cell seasily with bright practical application potential.

关键词： Cathode electrolyte interphase Sodium-ion batteries Full cell Ether-based electrolyte Vinylene carbonate DFT calculation

布比卡因+亚甲蓝混合液肛周封闭联合中药熏蒸对混合痔嵌顿术后的效果观察

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中国医学创新 2024年第15期21卷 10-14页

作者：万焱华王日玮万莎莎九江市第一人民医院普外三科江西九江332000

目的:探究布比卡因+亚甲蓝混合液肛周封闭术联合中药熏蒸对混合痔嵌顿术后的效果。方法:2022年8月—2023年8月选取于九江市第一人民医院行手术治疗的混合痔嵌顿患者80例,用随机抽签法分为对照组(行中药熏蒸治疗)与观察组(行布比卡因+亚... 详细信息

目的:探究布比卡因+亚甲蓝混合液肛周封闭术联合中药熏蒸对混合痔嵌顿术后的效果。方法:2022年8月—2023年8月选取于九江市第一人民医院行手术治疗的混合痔嵌顿患者80例,用随机抽签法分为对照组(行中药熏蒸治疗)与观察组(行布比卡因+亚甲蓝混合液肛周封闭联合中药熏蒸治疗),各40例。比较两组临床疗效、疼痛程度、肛门功能、术后并发症。结果:与对照组(75.00%)比较,观察组总有效率(92.50%)显著更高(P<0.05)。术后24 h及治疗14 d后,两组视觉模拟评分法评分均较术前显著降低,且观察组[(3.39±0.87)、(1.82±0.56)分]较对照组[(4.27±1.03)、(2.37±0.70)分]均显著更低(P<0.05)。术后1个月,两组肛管最大收缩压、肛管静息压均升高,肛管高压带均缩短,且与对照组[(112.36±10.87)mmHg、(51.11±4.25)mmHg、(2.94±0.36)cm]比较,观察组肛管最大收缩压[(119.48±11.31)mmHg]、肛管静息压[(54.56±4.39)mmHg]均显著更高,肛管高压带[(2.71±0.28)cm]显著更短(P<0.05)。与对照组(27.50%)比较,观察组术后并发症发生率(10.00%)显著更低(P<0.05)。结论:布比卡因+亚甲蓝混合液肛周封闭联合中药熏蒸可减轻混合痔嵌顿患者术后疼痛,改善肛门功能,降低术后并发症发生率,促进患者术后恢复。

关键词：混合痔嵌顿布比卡因亚甲蓝肛周封闭术中药熏蒸

Pyrolysis Mechanism of a Cyclotriphosphazene-Based Flame-Retardant Epoxy Resin by ReaxFF Molecular Dynamics

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中国炼油与石油化工:英文版 2023年第3期25卷 136-152页

作者： Jiang Shuaijun Meng Weifeng wan Yongqing Qin Weihua Liu Xiaoqing Lan yanhua School of Environment and Safety Engineering North University of ChinaTaiyuan 030051China

Cyclotriphosphazene derivatives can effectively improve the flame retardancy and fire safety of epoxy resins(EPs)via their influence on the pyrolysis process.In this work,the effects of hexa(5-methyl-2-pyridinoxyl)cyclotriphosphazene(HMPOP)incorporation on the initial pyrolysis of an EP at 500–3500 K were studied using the ReaxFF method.The pyrolysis fragments,initial reaction pathways,and main products were identified for the EP and EP/HMPOP composites.The activation energies were derived by fitting the weight percentage curves for solid species during the pyrolysis reactions and the obtained values were in good agreement with experimental data.The initial EP pyrolysis reactions included four major decomposition modes,which primarily involved the cleavage of C–O and C–N bonds.The main pyrolysis products were H_(2)O,CO,C_(2)H_(4),and CH_(2)O.HMPOP bonded with the oxygen-containing fragments to form larger molecular fragments and reduced the amounts of C_(0)–C_(4) products,especially that of the harmful gas CH_(2)O.Thus,HMPOP promoted the formation of carbon clusters and reduced the generation of combustible gases,ultimately decreasing the capacity for fire propagation.

关键词： epoxy cyclotriphosphazene ReaxFF pyrolysis flame retardancy

维生素B_(6)对动脉粥样硬化小鼠血管内皮损伤的影响及作用机制

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新乡医学院学报 2024年第1期41卷 1-7页

作者：朱茉莉李怡霏李珍珍赵海燕刘艳华邱月万光瑞李鹏新乡医学院药学院河南新乡453003

目的探讨维生素B_(6)(VB_(6))对动脉粥样硬化(AS)小鼠血管内皮损伤的影响及作用机制。方法将36只ApoE-/-小鼠随机分为对照组、AS组、VB_(6)组、AS+LiCl组、AS+VB_(6)组和AS+VB_(6)+LiCl组,每组6只。AS组、AS+LiCl组、AS+VB_(6)组和AS+VB_(6)+LiCl组小鼠高脂饮食12周建立AS模型;对照组和VB_(6)组小鼠常规饮食、正常饮水12周。12周后,对照组小鼠常规饮食,每日给予和VB_(6)组等体积的生理盐水灌胃;VB_(6)组小鼠常规饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1));AS+LiCl组小鼠继续给予高脂饮食,每日灌胃给予LiCl(1 mg·kg^(-1));AS+VB_(6)组小鼠继续给予高脂饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1));AS+VB_(6)+LiCl组小鼠继续给予高脂饮食,每日灌胃给予VB_(6)(50 mg·kg^(-1))和LiCl(1 mg·kg^(-1));6组小鼠均干预4周。干预结束后,采用酶联免疫吸附试验检测各组小鼠血清中一氧化氮(NO)、丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性。苏木精-伊红染色观察各组小鼠胸主动脉组织形态,并计算AS斑块面积占血管总面积的百分比。离体血管环实验检测胸主动脉舒张率。免疫组织化学法检测胸主动脉中钠氢交换蛋白1(NHE1)表达。结果与对照组相比,AS组小鼠血清中NO水平和SOD活性显著下降,MDA水平显著升高(P0.05)。与AS组相比,AS+VB_(6)组小鼠血清中NO水平和SOD活性显著上升,MDA水平显著下降(P0.05)。与AS+VB_(6)组相比,AS+VB_(6)+LiCl组小鼠血清中NO水平和SOD活性显著下降,MDA水平显著升高(P0.05)。AS+VB_(6)组小鼠Ach诱导的胸主动脉舒张率显著低于AS组(P0.05)。AS+VB_(6)+LiCl组小鼠Ach诱导的胸主动脉舒张率显著高于AS+VB_(6)组(P0.05)。AS组小鼠胸主动脉中NHE1蛋白表达量百分比显著高于对照组(P0.05)。AS+VB_(6)组小鼠胸主动脉中NHE1蛋白表达量百分比显著低于AS组(P0.05)。AS+VB_(6)+LiCl组小鼠胸主动脉中NHE1蛋白表达量百分比显著高于AS+VB_(6)组(P<0.05)。结论VB_(6)可通过抑制NHE1蛋白的表达来改善AS小鼠的血管内皮损伤。

关键词：维生素B_(6) 钠氢交换蛋白1 内皮损伤动脉粥样硬化氧化应激

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基于肠道菌群探讨中医治疗多囊卵巢综合征

世界中医药 2024年第5期19卷 712-718页

作者：张婉玉张燕丽付新万天恩刘理凤马呈呈韩延华吴效科常惠黑龙江中医药大学哈尔滨150040 黑龙江中医药大学附属第一医院哈尔滨150040

多囊卵巢综合征(PCOS)是一种生殖内分泌紊乱和代谢异常的疾病,常见于育龄期女性。近年研究表明PCOS可表现为不同程度的肠道菌群异常。肠道菌群参与了PCOS的高雄激素血症、卵泡发育异常、胰岛素抵抗、肥胖和生殖内分泌异常等多个环节。... 详细信息

多囊卵巢综合征(PCOS)是一种生殖内分泌紊乱和代谢异常的疾病,常见于育龄期女性。近年研究表明PCOS可表现为不同程度的肠道菌群异常。肠道菌群参与了PCOS的高雄激素血症、卵泡发育异常、胰岛素抵抗、肥胖和生殖内分泌异常等多个环节。基于肠道菌群的PCOS干预主要体现在饮食、运动等生活方式以及益生菌对肠道菌群的调节作用,中医药包括中草药、针灸以及其他中医特色疗法,可通过干预肠道菌群治疗PCOS。本综述为下一步PCOS肠道菌群临床研究和临床治疗PCOS提供了参考依据。

关键词：多囊卵巢综合征肠道菌群发病机制高雄激素血症中医中药针刺治法

超声辅助下穿支螺旋桨皮瓣修复足踝部软组织缺损26例

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中华显微外科杂志 2024年第3期47卷 273-279页

作者：李俊明庄艳芳马广辉代彭威宛磊李艳华李道选黄贺军应世闯张毅漯河医学高等专科学校第二附属医院显微骨科河南漯河462300

目的探讨穿支螺旋桨皮瓣(PPPF)修复足踝部软组织缺损的临床效果以及术前超声辅助供区穿支定位的作用。方法2017年1月-2023年6月,漯河医学高等专科学校第二附属医院显微骨科应用PPPF修复26例足踝部中、小面积软组织缺损,其中男17例,女9例... 详细信息

目的探讨穿支螺旋桨皮瓣(PPPF)修复足踝部软组织缺损的临床效果以及术前超声辅助供区穿支定位的作用。方法2017年1月-2023年6月,漯河医学高等专科学校第二附属医院显微骨科应用PPPF修复26例足踝部中、小面积软组织缺损,其中男17例,女9例,年龄18~68岁,平均46岁。缺损部位:前足3例,中足6例,均合并不同程度的肌腱外露、骨外露;足踝部、足跟部软组织缺损17例,合并不同程度骨外露、踝关节开放12例,跟腱外露5例。软组织缺损面积2.5 cm×1.5 cm~16.0 cm×6.5 cm。术前测量创面宽度,HHD在创面近端探测供区穿支,高频CDU再次定位确认穿支发出位置、走行、血流量、管径、2条穿支标记点连线为皮瓣中轴线,利用"提捏法"评估供区可直接闭合或应用接力皮瓣可闭合供区。皮瓣切取面积2.8 cm×1.5 cm~24.0 cm×7.5 cm,供区直接闭合22例,接力皮瓣修复4例。皮瓣携带皮神经与受区皮神经缝接4例。合并骨缺损同期行Masquelet技术6例。出院后前2个月间隔1~2周门诊复查1次,骨缺损植骨患者1~2个月复查X线片直至骨缺损骨性愈合。结果仅1例术后24 h出现皮瓣瘀血、肿胀,远端血运差,给予拆除蒂部部分缝线,1周后皮瓣尖端仍出现小面积坏死,经换药后愈合,其余皮瓣未经特殊处理顺利成活。21例得到4个月~3年的随访,皮瓣外形、颜色、质地满意,无溃疡。皮瓣感觉恢复评定按照英国医学研究会(BMRC)评定标准,缝接神经的3例皮瓣感觉恢复至S 2级1例,S 3级2例;据美国足踝关节协会(AOFAS)踝-后足功能评分结果优16例,良5例。结论超声辅助下PPPF可有效修复足踝部软组织缺损。

关键词：穿支螺旋桨皮瓣超声修复足踝部显微外科技术

Long-pulse, single-frequency 1064 nm laser and frequency doubling

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High Power Laser Science and Engineering 2015年第3期3卷 66-70页

作者： Xiafei Xu Gang Xie yanhua Lu Lei Zhang Min wan Institute of Applied Electronics CAEP Graduate School of China Academy of Engineering Physics

An all-solid-state single-frequency 1064 nm laser with a 100 μs pulse width, 500 Hz repetition rate and 700 m J single pulse energy is designed using seed injection and a three-stage master oscillator power amplifier(MOPA) construction.Using this as a basis, research on long-pulse laser frequency doubling is carried out. By designing and optimizing the lithium triborate(LBO) crystal, the theoretically calculated maximum conversion efficiency ηmax reaches 68% at M2=1, while ηminis 33% at M2=3. Generation of 212 m J pulses of green light with a repetition rate as high as500 Hz is obtained from a fundamental energy of 700 m J. The experimental conversion efficiency reaches 31% and the power stability is better than±1%.

关键词： all-solid-state frequency doubling MOPA construction single-frequency laser