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富锂层状氧化物正极材料的微观结构调控及其性能研究

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浙江工业大学学报 2024年第4期52卷 355-363页

作者：高静李瑛顾可欣顾庆文邱报刘兆平浙江工业大学化学工程学院浙江杭州310014 中国科学院宁波材料技术与工程研究所浙江宁波315201

通过调整富锂层状氧化物正极材料的元素组成,实现对其体相结构内的类Li_(2)MnO_(3)相晶畴分散度的调控。通过结合高功率X射线衍射和球差电镜证明了Li_(1.08)Ni_(0.225)Co_(0.225)Mn_(0.450)O_(2)材料具有高度分散的类Li 2MnO_(3)相晶畴... 详细信息

通过调整富锂层状氧化物正极材料的元素组成,实现对其体相结构内的类Li_(2)MnO_(3)相晶畴分散度的调控。通过结合高功率X射线衍射和球差电镜证明了Li_(1.08)Ni_(0.225)Co_(0.225)Mn_(0.450)O_(2)材料具有高度分散的类Li 2MnO_(3)相晶畴,同时原位微分电化学质谱测试证明了具有高度分散的类Li_(2)MnO_(3)相晶畴的富锂层状氧化物正极材料可以成功抑制晶格氧的释放。电化学测试表明:微观结构的调控虽然可以提高材料的首次库伦效率和平均放电电压,但同时也降低了晶格氧的活性,减少了放电比容量。在循环过程中晶格氧稳定性的提高减轻了结构的退化程度,富锂层状氧化物正极材料表现出更优异的循环稳定性和更缓慢的电压衰减。此外,晶格氧稳定性的提高还改善了材料的热稳定性。

关键词：富锂层状氧化物正极材料微观结构氧释放热稳定性

Optimal Initialization and Starting Approach of Synchronous Condenser Integrated Power Grid

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 248-260页

作者： Puyu Wang Xing Liu qingwen Mou Tao Yuan Tianming gu Hemin Yang Xiao-Ping Zhang Zhengrong Xiang Chunyi guo School of Automation Nanjing University of Science and TechnologyNanjing 210094China NARI Group Corporation/State Grid EPRI and also with NARI Technology Co.Ltd. Nanjing 211106China School of Engineering University of BirminghamBirminghamB152TTUnited Kingdom State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Synchronous condensers(SCs)are generally used at the receiving-end stations of ultra-high-voltage direct current(UHVDC)transmission systems due to their strong reactive power support and flexible regulation of reactive power according to the interconnected grids operating *** this paper,different starting control schemes of a SC integrated power grid are investigated providing four main contributions:1)The principle of reactive power support of the SC on the interconnected power grid is analytically studied,providing the establishment of mathematical models.2)Four different starting control schemes are developed for the initialization and SC integration,*** Scheme 1,a preset initial falling speed is directly utilized without initialization;in Scheme 2,a black start sequential control approach with a static frequency converter(SFC)is proposed;in Scheme 3,PI/PD/PID controllers are respectively applied for the excitation device at the speed-falling stage;in Scheme 4,a pre-insertion approach of an energy absorption component with R/L/RL is utilized to suppress the surges at the SC integration instant.3)The dynamic behaviors of four different starting schemes at specific operating stages are evaluated.4)The success rate of SC integration is analyzed to evaluate starting control *** of the SC interconnected system with four different starting control schemes is evaluated in the timedomain simulation environment PSCAD/EMTDC^(TM).The results prove the superiority of the proposed starting control approach in Scheme 4.

关键词： Black start dynamic behaviors excitation system pre-insertion of energy absorption components starting control schemes static frequency converter(SFC) success rate of integration synchronous condenser(SC)

Selective Oxidation of Glycerol with Hydrogen Peroxide Using Silica- Encapsulated Heteropolyacid Catalyst

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物理化学学报 2018年第8期34卷 886-895页

作者： YUAN Mingming LI Difan ZHAO Xiuge MA Wenbao KONG Kang NI Wenxiu gu qingwen HOU Zhenshan Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai 200237 P. R. China.

The Keggin type heteropolyacids (HPAs) have attracted increasing attention due to their strong Bronsted acidity and excellent redox properties, which could play an important role in accelerating the conversion of bio-derived molecules. In this work, heteropolyacid (HPA, H_4PMo_(11)VO_(40)) encapsulated by silica was synthesized by a sol-gel method and a sequential silylation technique (HPA@SiO_2-N_2-S). The as-synthesized material was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The FT-IR spectra show that the HPA anions preserved their Keggin structure when incorporated into the catalyst. The XRD patterns show that HPA molecules are uniformly dispersed within the silica network. The SEM and TEM images confirm that the catalyst was composed of spherical nanometer-sized particles. The porous properties of the catalysts measured by the N_2 adsorption-desorption isotherms indicate that the Brunauer, Emmett and Teller (BET) surface area of pure SiO_2 was 287 m~2·g~(–1), but upon encapsulation of HPA into the silica matrix, a lower surface area (245 m~2·g~(–1)) was measured for the resulting material. In addition, the pore diameter was reduced after silylation. Furthermore, the hydrophobicity of the catalysts was investigated by the measurement of contact angle (CA) with water. The SiO_2 and SiO_2/HPA catalysts were completely hydrophilic and the contact angle was close to 0°. However, the contact angle of the silylated catalyst was determined to be 137°, indicating that the silylation procedure significantly increased the hydrophobicity of the catalyst. The as-prepared catalysts were also used as heterogeneous catalysts for the selective oxidation of glycerol. The prepared material exhibited excellent catalytic activity towards glycerol oxidation, in which the glycerol can be selectively transformed into formic ac

关键词：杂多酸化学分析二氧化硅合成方法

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从日本古典诗歌看中日审美情趣差异

外语教学 2008年第4期29卷 70-73页

作者：顾庆文西安外国语大学基础教学部陕西西安710128

古典诗歌能够集中、深刻地反映出一个民族的审美情趣。日本古典诗歌的时间感分外强烈,热衷于表现瞬间的美感,日本人对时间的感受是过去、现在和将来的同一性。日本人认为死是人存在的固有状态,是生命的一部分,死在日本人眼中是积极的。... 详细信息

古典诗歌能够集中、深刻地反映出一个民族的审美情趣。日本古典诗歌的时间感分外强烈,热衷于表现瞬间的美感,日本人对时间的感受是过去、现在和将来的同一性。日本人认为死是人存在的固有状态,是生命的一部分,死在日本人眼中是积极的。日本古典诗歌不求境界的开阔,不注重空间的浩大与深邃,整体上流露出一股纤巧玲珑的气质。日本人对自然美和色彩美的感觉特别敏锐和纤细,含有丰富的艺术性。

关键词：日本古典诗歌时间感生死观空间感自然观

Layered perovskite oxide Y_(0.8)Ca_(0.2)BaCoFeO_(5+δ) as a novel cathode material for intermediate-temperature solid oxide fuel cells

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Journal of Rare Earths 2015年第5期33卷 519-523页

作者：余良浩陈永红顾庆文田冬卢肖永孟广耀林彬 Anhui Key Laboratory of Low Temperature Co-fired Materials Department of Chemistry and Engineering Huainan Normal University School of Chemical Engineering Anhui University of Science and Technology

A layered perovskite oxide Y0.8Ca0.2BaCoFeO5＋δ（YCBCF） was synthesized as a novel cathode material for intermedi-ate-temperature solid oxide fuel cells （IT-SOFCs） by citric acid-nitrates self-propagating combustion method. The phase and micro-structure of YCBCF were investigated by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, respectively. The aver-age thermal expansion coefficient （TEC） of YCBCF was 14.6×10–6 K–1, which was close to other materials of SOFC at the range of RT–1000 oC. An open-circuit potential of 0.75 V and a maximum output power density of 426 mW/cm2 were obtained at 650 oC in a Sm0.2Ce0.8O1.9 （SDC）-based anode-supported SOFC by using humidified （~3%H2O） hydrogen as fuel and static air as oxidant. The results indicated that the YCBCF was a promising cathode candidate for IT-SOFCs.

关键词： solid oxide fuel cell cathode perovskite Sm0.2Ce0.8O1.9 rare earths

国产新型DSA设备在椎体成型术中的辐射剂量临床对照研究

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临床放射学杂志 2023年第5期42卷 836-840页

作者：梁胜凯谷青文计佳杰赵国峰柏志斌秦永林东南大学医学院南京210009 江苏省南京市东南大学附属中大医院介入与血管外科 210009

目的通过对比两台数字减影血管造影设备在椎体成形术中的辐射剂量大小,探究国产新型DSA设备的辐射水平。方法对择期行椎体成形术的患者按其身体质量指数(BMI)相差5%范围进行配对后,分别随机分配到实验组[联影uAngio (UIuA)]和对照组[... 详细信息

目的通过对比两台数字减影血管造影设备在椎体成形术中的辐射剂量大小,探究国产新型DSA设备的辐射水平。方法对择期行椎体成形术的患者按其身体质量指数(BMI)相差5%范围进行配对后,分别随机分配到实验组[联影uAngio (UIuA)]和对照组[西门子Axiom Zee Biplane (SAZB)]。对比分析两台设备手术的图像质量评价、透视时间(T)、剂量-面积乘积率(DAP率)、空气比释动能率(K剂量率)以及患者手术部位躯体左右两侧入射体表剂量(ESD)大小。结果 UIuA的透视及点片图像评价与SAZB无显著差异;UIuA的DAP剂量率(31.88;24.01~44.15μGy·mm^(2)/min)显著低于SAZB(63.73;51.62~80.26μGy·mm^(2)/min),P=0.022。K剂量率比较,UIuA(4.74;3.17~5.97 mGy/min)与SAZB(5.76;4.58~8.73 mGy/min)无显著性差异(P=0.074)。联影uAngio设备患者左、右两侧ESD显著低于西门子Axiom Zee Biplane,P值均<0.05。结论在同等图像质量评分的前提下,国产DSA设备UIuA在辐射剂量上表现优于SAZB。UIuA对降低辐射暴露从而减少放射性损害,以及对我国介入诊疗辐射安全环境的改善有重要意义。

关键词：椎体成形术 DSA设备辐射剂量配对分析

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新型国产DSA设备易用性和辐射剂量分析

介入放射学杂志 2023年第3期32卷 284-287页

作者：谷青文计佳杰梁胜凯赵国峰柏志斌秦永林东南大学附属中大医院介入与血管外科江苏南京210009 东南大学医学院

目的探究新型国产低剂量DSA造影设备剂量降低技术的临床应用效果,为国产DSA设备改进提供参考。方法选择接受择期脑血管造影患者并基于其体质量指数配对,配对成功后随机分配到试验组(联影uAngio)和对照组(西门子Axiom Zee Biplane)。... 详细信息

目的探究新型国产低剂量DSA造影设备剂量降低技术的临床应用效果,为国产DSA设备改进提供参考。方法选择接受择期脑血管造影患者并基于其体质量指数配对,配对成功后随机分配到试验组(联影uAngio)和对照组(西门子Axiom Zee Biplane)。评价术中图像质量和设备各操控性能,记录设备的剂量-面积乘积(DAP)率、空气比释动能率(K值率)。测定介入放射治疗过程中患者各测量点辐射剂量。综合评估联影uAngio剂量降低技术的临床应用效果。结果国产DSA设备联影uAngio图像质量与西门子Axiom Zee Biplane无显著差异,多项操控性能显著优于西门子Axiom Zee Biplane。联影uAngio的DAP率显著低于西门子Axiom Zee Biplane(P=0.001)。两组患者各测量点辐射剂量无显著差异。结论与西门子Axiom Zee Biplane相比,国产DSA设备联影uAngio在具备相似水准图像质量和更加良好的操作易用性前提下,其DAP率更低。

关键词： DSA设备图像质量临床易用性辐射剂量

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小波分析在心磁信号辅助诊断中的应用

现代科学仪器 2007年第6期24卷 64-67页

作者：顾晴雯蒋式勤同济大学电子与信息工程学院上海201804

本文用小波变换方法,分析了用超导量子干涉器(SQUID)检测得到的人体心磁信号的频率,提取了它的瞬时频率和包络信息,建立了表征QRS波群形状变异的参数P_N,Q_N,V_P和V_Q。通过数字仿真,检验了这些参数的效果,并给出了多组心磁实测数据表... 详细信息

本文用小波变换方法,分析了用超导量子干涉器(SQUID)检测得到的人体心磁信号的频率,提取了它的瞬时频率和包络信息,建立了表征QRS波群形状变异的参数P_N,Q_N,V_P和V_Q。通过数字仿真,检验了这些参数的效果,并给出了多组心磁实测数据表征参数的分析结果。

关键词：心磁信号小波变换信息提取 SQUID

新型复合阴极Sr_(0.95)Ti_(0.05)Co_(0.95)O_(3-δ)–Sm_(0.2)Ce_(0.8)O_(1.9)在中低温固体氧化物燃料电池中的性能

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硅酸盐学报 2015年第7期43卷 852-857页

作者：余良浩王晓晴林彬田冬卢肖永顾庆文陈永红安徽理工大学化学工程学院安徽淮南232001 淮南低温共烧材料省级重点实验室淮南师范学院化学与化工系安徽淮南232001

采用柠檬酸自蔓延燃烧法合成了 Sr0.95Ti0.05Co0.95O3？δ（STC）阴极粉体和 Sm0.2Ce0.8O1.9（SDC）电解质粉体,将 STC 与SDC 粉体按质量比7：3混合得到复合阴极。通过 X 射线衍射（XRD）、直流四端子法和热膨胀仪表征了样品的化学相容... 详细信息

采用柠檬酸自蔓延燃烧法合成了 Sr0.95Ti0.05Co0.95O3？δ（STC）阴极粉体和 Sm0.2Ce0.8O1.9（SDC）电解质粉体,将 STC 与SDC 粉体按质量比7：3混合得到复合阴极。通过 X 射线衍射（XRD）、直流四端子法和热膨胀仪表征了样品的化学相容性、电导率和热膨胀系数。XRD 表明，STC 在900℃能够得到立方纯钙钛矿结构，复合阴极 STC？SDC 在工作温度区间内具有很好的化学相容性；在650℃空气气氛下 STC？SDC 与 SDC 之间的界面极化阻抗仅为0.05Ω·cm2。制备了阳极支持型（NiO-SDC│SDC│STC？SDC）单电池,在450～650℃范围内以湿润的 H2（3%水蒸汽）为燃料气，空气为氧化剂测试了单电池的性能。结果表明：阳极支撑的单电池共烧1350℃可以得到致密的电解质层和多孔的电极,而且650℃时单电池开路电压0.82 V，最大输出功率为721 mW/cm2。结果预示，在以 SDC 为电解质的中低温固体氧化物燃料电池（IT-SOFC）中，STC-SDC 是一个很有前途的复合阴极材料。

关键词：复合阴极极化阻抗最大功率中低温固体氧化物燃料电池