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PVP/PAN-derived porous carbon fiber for zinc-ion hybrid supercapacitors

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Rare Metals 2024年第7期43卷 3066-3073页

作者： Shu-Hua Yang Wen-qing Fu Yan-Wei cui Bing-Qiang Cao Materials Center for Energy and Photoelectrochemical Conversion School of Material Science and EngineeringUniversity of JinanJinan 250022China

Porous carbon fibers are promising cathodes for zinc-ion hybrid supercapacitors(ZHSs)owing to their abundant active sites,great conductivity,and stable physical and chemical ***,designing a proper preparation technique to regulate the microstructure of carbon fibers still remains a great ***,a poly vinylpyrrolidone/po-lyacry lonitrile(PVP/PAN)-derived porous carbon fiber is developed via the PVP/PAN blend electrospinning and hydrothermal selective PVP removal *** hydrothermal selective PVP removal strategy can effectively avoid a cross-linking between PVP and PAN during the traditional stabilization at air *** PVP/PAN-derived porous carbon fiber,the sufficient micropores provide abundant space for the Zn^(2+)storage,whereas the proper mesopores contribute to the fast ion *** hierarchical porous structures endow ZHSs with high specific capacity and high-rate *** ZHS assembled with the optimal PVP/PAN-derived porous carbon fiber(PVP-PANC-0.8)displays an outstanding specific capacity of 208 mAh·g^(-1),high rate capability(49.5%)from 0.5 to 5 A·g^(-1),and 72.25%capacity retention after 10,000 cycles at 0.5 A·g^(-1).

关键词： Zinc-ion hybrid supercapacitors Porous carbon fibers Hierarchical porous structures Electrospinning

超高层建筑顶部临边与悬挑钢桁架装饰柱吊装施工

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建筑技术 2024年第6期55卷 654-659页

作者：李春辉王岩孙军令马靖原崔庆军北京新航城控股有限公司北京102602 北京博大经开建设有限公司北京100176 航天规划设计集团有限公司北京102627

以北京市某超高层国际化商务综合体项目为例,介绍了超高层建筑顶部临边与悬挑钢桁架装饰柱的设计概况、钢桁架深化设计与施工部署,通过使用现场塔式起重机,设置超高层施工操作平台的方法,阐述了超高层建筑顶部屋面临边钢桁架柱和塔楼四... 详细信息

以北京市某超高层国际化商务综合体项目为例,介绍了超高层建筑顶部临边与悬挑钢桁架装饰柱的设计概况、钢桁架深化设计与施工部署,通过使用现场塔式起重机,设置超高层施工操作平台的方法,阐述了超高层建筑顶部屋面临边钢桁架柱和塔楼四周悬挑造型钢桁架柱的工艺流程和施工操作要点,重点将2种造型钢结构柱分段吊装的措施和拼接过程进行介绍;通过该吊装施工技术的应用,确保了工程的质量和安全。

关键词：超高层钢桁架柱临边与悬挑吊装施工

PRESSURE DISTRIBUTION ON THE WALL OF THE INNER CYLINDER RECIPROCATING AXIALLY TO THE UNSTEADY FLOW OF VISCOELASTIC FLUID IN ECCENTRIC ANNULUS

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Journal of Hydrodynamics 2006年第5期18卷 606-612页

作者： WANG Yan cui Hai-qing YANG Yuan-jian GUO Jun-hui LI Nan Department of Petroleum Engineering China University of Petroleum Beijing 102249 China Department of Petroleum Engineering Daqing Petroleum Institute Daqing 163318 China

In this article, the governing equations for the unsteady flow of viscoelastic fluid in the eccentric annulus with the inner cylinder reciprocating axially and the expression of the pressure distribution on the wall of the inner cylinder of the annulus are established and derived, respectively, under the bipolar coordinate system. The equations and the expression are solved and calculated numerically using the finite difference method, respectively. The curves of the pressure distribution on the wall of the inner cylinder of the aqueous solution of Hydrolyzed Polyacrylamide （HPAM） are plotted and the influences of annular eccentricity, stroke, and stroke frequency on the pressure distribution are analyzed.

关键词： viscoelastic unsteady flow eccentric annulus fluid reciprocating axially pressure distribution

Insight-HXMT observations of the Crab pulsar

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Research in Astronomy and Astrophysics 2019年第6期19卷 109-116页

作者： You-Li Tuo Ming-Yu Ge Li-Ming Song Lin-Li Yan qing-cui Bu Jin-Lu Qu Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China University of the Chinese Academy of Sciences Beijing 100049 China School of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We report on X-ray emission properties of the Crab pulsar(PSR B0531+21) using observations by Insight-HXMT during its first year after launch. We obtained high signal-to-noise profiles in the X-ray energy band 11–250 keV. We have confirmed an increase in the flux ratio of the second peak over the main peak with increasing energy, consistent with other missions. The separation of the two peaks shows no significant trend with increasing energy. The phase-averaged spectrum, fitted by a logpar model, and the phase-resolved spectra of the Crab pulsar, fitted by a powerlaw in the different energy bands of HXMT, are consistent with RXTE and NuSTAR in that photon indices evolve as a function of phase as well as a function of energy, contributing to a broadband modeling.

关键词： stars neutron star-pulsars individual(Crab)-X-rays

Determination of phenolic whitening agents in cosmetics by micellar electrokinetic capillary chromatography with amperometric detection

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Chinese Chemical Letters 2013年第7期24卷 636-638页

作者： Wei Jin Wei-Yu Wang Yu-Lian Zhang Yong-Jian Yang qing-cui Chu Jian-Nong Ye Department of Chemistry East China Normal University Shanghai Institute for Food and Drug Control

A sensitive method for simultaneous determination of six phenolic whitening agents, including arbutin, phenol, resorcinol, hydroquinone, kojic acid, and salicylic acid in cosmetics has been developed using micellar electrokinetic capillary chromatography with amperometric detection （MECC-AD）. Effects of several factors, such as the pH value and concentration of running buffer, potential applied to the working electrode, separation voltage, and injection time were investigated to obtain optimum conditions for separation and detection. With a 75 cm long fused-silica capillary tube, well-defined separation of six phenolic compounds was achieved in 10 mmol/L SDS/40 mmol/L H3BO3-Na2B407 running buffer （pH 9.0）. Good linear relationship was obtained for each analyte over three orders of magnitude with correlation coefficients （r2） between 0.9985 and 0.9994, and the detection limit （S/N = 3） ranged from 0.04 p^g/mL to 0.45 p^g/mL. The proposed method has been successfully applied for the determination of phenolic whitening agents in real cosmetic samples with satisfactory results, providing an alternative monitoring method for cosmetics safety regulation.

关键词： Micellar electrokinetic capillary chromatography Amperometric detection Phenolic whitening agents Cosmetics

On quantitative structure-activity relationships between hydrazine derivatives and β irradiation

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Nuclear Science and Techniques 2018年第5期29卷 36-43页

作者： Ling-Yu Wang Yan Wang Da-qing cui Song-Tao Xiao Xiao-Dong Liu Ying-Gen OuYang Cong Huang Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of TechnologyNanchang 330013China China Institute of Atomic Energy Beijing 102413China 123

In this study, solutions of hydrazine and its derivatives were irradiated using a pulsed electron beam to determine the half-reaction time of radiolysis. 3 D structures of the hydrazine derivatives were optimized, and their energies were calculated using density functional theory with the B3 LYP method and 6-311 +(3 d, 3 p) basis *** the first time, the 3 D quantitative structure-activity relationship(QSAR) equation describing the relationship between the hydrazine derivative structures and rate of radiolysis has been established using SPSS *** correlation analysis revealed a close correlation between the total energies of the molecules and half-reaction times. In the QSAR equation, Y =-7583.464 +54.687 X_1+94333.586 X_2,Y,X_1,and X_2 are the half-reaction time, total energy of the molecule, and orbital transition energy, respectively. The significance levels of the regression coefficients were 0.006 and 0.031, i.e., both less than 0.05. Thus, this model fully explains the relationship between hydrazine derivatives and β radiolysis *** results show that the total energy of the molecule and orbital transition energy are the main factors that influence the β radiolysis stability of these hydrazine derivatives.

关键词： Hydrazine derivatives βIrradiation Radiolysis stability Quantitative structure–activity relationships

复杂作用关系过程的区域显著性实验设计及全局建模方法

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系统工程理论与实践 2013年第9期33卷 2249-2262页

作者：崔庆安郑州大学管理工程学院郑州450001

针对参数与质量特性之间作用关系复杂过程的参数优化,提出一种基于质量特性变化显著程度的序贯设计及全局建模方法.首先以均匀设计为基础,将其拆分形成一系列的设计点集和添加点集;其次利用初始设计点集建立过程的支持向量回归(SVR)模型... 详细信息

针对参数与质量特性之间作用关系复杂过程的参数优化,提出一种基于质量特性变化显著程度的序贯设计及全局建模方法.首先以均匀设计为基础,将其拆分形成一系列的设计点集和添加点集;其次利用初始设计点集建立过程的支持向量回归(SVR)模型,并对建模样本点进行Ward聚类,由此将可行域划分成若干子区域,并以各子区域支持向量的比率反映该子区域质量特性变化的显著程度;而后以欧氏距离为判别依据,将添加点集中的实验点划分至合适的子区域,根据"子区域间区别对待,子区域内均匀分散"的原则,调整各子区域内添加实验点的数目,在支持向量率较高的子区域添加较多实验点;上述步骤迭代进行直至满足终止准则,再拟合过程最终的SVR模型.仿真与实证研究表明,与基于"均匀分散"原则的传统均匀设计和超拉丁方抽样相比,所提方法的实验设计效率与模型性能均有较大提高:实验点可以有针对性地集中分布于质量特性变化较为显著的子区域,模型预测误差降低了29.8%以上,而且能够以较小的样本量发现过程的多个极值,得到更优的参数优化结果.

关键词：实验设计建模复杂作用关系支持向量回归机参数优化

面向多极值质量特性的全局式序贯性实验设计方法

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系统工程理论与实践 2012年第10期32卷 2143-2153页

作者：崔庆安郑州大学管理科学与工程学院郑州450001

针对多极值质量特性的全局性建模和参数优化问题,为降低实验设计样本量,提高模型预测性能,提出一种全局式序贯性设计方法.首先在一定的初始实验设计方式下,建立过程粗略的SVR模型:而后根据模型中支持向量的分布,在支持向量样本各维度的4... 详细信息

针对多极值质量特性的全局性建模和参数优化问题,为降低实验设计样本量,提高模型预测性能,提出一种全局式序贯性设计方法.首先在一定的初始实验设计方式下,建立过程粗略的SVR模型:而后根据模型中支持向量的分布,在支持向量样本各维度的45度角或轴向方向同步地增加实验点,再拟合过程新的SVR模型;如此迭代进行,当模型精度达到要求或样本量达到上限时终止序贯性设计.仿真与实证研究表明,该方法能够在可行域全局的范围内将实验点合理地分配在质量特性的多个极值附近,避免了传统的单路径式序贯性设计只能发现单个极值的不足,充分提高了实验效率;与均匀空间网格设计、拉丁超立方设计和均匀设计相比,在样本量接近的情况下,基于全局式序贯性设计的SVR模型的预测均方误差至少降低了30%;而在预测误差较为接近的情况下,全局式序贯性设计的样本量至少降低了12%.

关键词：序贯性设计多极值质量特性支持向量回归机参数优化质量改进

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大运河安徽段文物遗产空间可视化分析

蚌埠学院学报 2024年第5期13卷 83-89页

作者：白如山崔梦晴陈玲玲倪梦影夏宇阜阳师范大学历史文化与旅游学院安徽阜阳236037

运用GIS空间分析工具对大运河安徽段文物遗产进行可视化分析,结果发现:从空间维度看,大运河安徽段文物遗产具有明显的集聚特征,濉溪县与埇桥区交界处为核心集聚区。从时间维度看,大运河安徽段文物遗产演化特征因时各异。文物遗产分布重... 详细信息

运用GIS空间分析工具对大运河安徽段文物遗产进行可视化分析,结果发现:从空间维度看,大运河安徽段文物遗产具有明显的集聚特征,濉溪县与埇桥区交界处为核心集聚区。从时间维度看,大运河安徽段文物遗产演化特征因时各异。文物遗产分布重心总体上由东南向西北呈Z字形演化态势,演化格局经历了“多核-单核-双核-多点”的空间过程。从类型维度看,大运河安徽段文物遗产空间分布形态因类各异,古遗址、古墓葬和古建筑三类文物遗产呈集聚分布,而近现代类文物遗产的分布较为分散。据此提出有待做好“规划”,做特“研学”和做精“智慧”。

关键词：文物遗产空间格局安徽大运河可视化分析