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Kinetics and Mechanism of Iridium(Ⅲ)-Catalyzed Oxidation of Ethanol Amine by Cerium(Ⅳ) in Sulfuric Acid Media

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Chemical Research in Chinese Universities 2007年第3期23卷 333-338页

作者： ZHAI Yong-qing LIU Hong-mei yang Lin yang Guo-zhong SONG Wen-yu LIU Yu-kai College of Chemistry and Environmental Science Hebei University Baoding 071002 P. R. China

In this study, the kinetics and mechanism of the iridium（ Ⅲ ） -catalyzed oxidation of ethanol amine（EAN） by cerium（Ⅳ） in a sulfuric acid medium was investigated using titrimetric technique of redox in a temperature range of 298--313 K. It was found that the reaction is of first order with respect to Ce（ Ⅳ ） and It（ Ⅲ ）, and a positive fractional order with respect to EAN. It was also found that the pseudo-first-order （ [EAN ] 〉〉 [ Ce （ Ⅳ） ] ） rate constant koba decreases with the increase of [ H^＋ ] and [ HSO^-4 ]. Under the protection of nitrogen gas, the reaction system can initiate the polymerization of acrylonitrile, indicating the generation of free radicals. On the basis of the experimental results, a suitable mechanism was proposed. From the dependence of koba on the concentration of hydrogen sulfate, Ce（SO4）2 was found to be the kinetically active species. The rate constants of the rote-determining step together with the activation parameters were evaluated.

关键词： Iridium(Ⅲ) ion Cerium(Ⅳ) ion Ethanol amine Catalytic oxidization Kinetics and mechanism

Electronic structure and photoelectron spectrum Assignment of allene

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Chinese Journal of Chemistry 1993年第5期11卷 406-411页

作者： WANG,Zhi-zhong yang,Ming yang,zhong-Zhi Institute of Theoretical Chemistry and State Key Laboratory of Computational Theoretical Chemistry,Jilin University,Changchun,Jilin 130023 Institute of Theoretical Chemistry and State Key Laboratory of Computational Theoretical Chemistry Jilin University Changchun Jilin 130023

In this paper a series of ab initio SCF and configuration calculations were reported for the ground state and excited states X^2E, A^2E,~2B_2 and ~2A_1 of *** ground state X^2E Jahn- Teller distorsion was discussed and a twisted angle of 50° and a torsional barriers of 0.21—0.51 eV were *** on calculated results,the experimental photoelectron spectrum of allene has been assigned.

关键词： SCF Electronic structure and photoelectron spectrum Assignment of allene Cl

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng Wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin zhong Wenwen yang Peng Gao Lezhi yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy

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河道型水库总磷预测模型的建立及应用

西南交通大学学报 2004年第5期39卷 653-655页

作者：刘洋杨立中西南交通大学环境科学与工程学院四川成都610031

根据河道型水库特有的水文、水力条件,按各水期的不同情况分别将直角坐标系下的二维河流污染物扩散模型和极坐标下的AB卡拉乌舍夫扩散模型结合起来,建立了河道型水库的总磷预测模型,并将其应用于水深不超过5m的狭长型河道水库.以绵阳市... 详细信息

根据河道型水库特有的水文、水力条件,按各水期的不同情况分别将直角坐标系下的二维河流污染物扩散模型和极坐标下的AB卡拉乌舍夫扩散模型结合起来,建立了河道型水库的总磷预测模型,并将其应用于水深不超过5m的狭长型河道水库.以绵阳市三江水库为例,用此模型模拟并预测库区水体中总磷的浓度变化,计算结果与观测值的相对误差小于10%.

关键词：河道型水库总磷预测模型富营养化

THEORETICAL STUDY ON COAXIAL MULTIMODE FEEDS

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Science China Mathematics 1989年第12期32卷 1499-1510页

作者：杨可忠杨志友高健章日荣 Shijiazhuang Communication Telemetry and Telecontrol Research Institute

Using the moment method the mode ratio formulas are derived for coaxial multimode feeds. First, using the geometrical thoery of diffraction, the fields are found over an infinite plane which is one wavelength away from the feed aperture, and then, based on these fields, the radiation field of the feed is evaluated. The good agreement between the theoretical and the measured results shows the method presented is available.

关键词： coaxial multimode dispersion procedure geometrical diffraction.

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基于HSMM的铝空电池后期SOC估计

电子科技大学学报 2017年第2期46卷 380-385页

作者：张榆平陈栋罗杨杨忠孝朱贤彬罗安源电子科技大学自动化工程学院成都6111731

电池荷电状态(SOC)的估算精度是影响新能源汽车性能的重要因素之一。传统的安时法由于累积误差较大始终无法满足精确的SOC估计。该文采用基于隐半马尔可夫模型(HSMM)的SOC预测作为安时法的一个补充,使铝空电池后期估计精度可以得到保障... 详细信息

电池荷电状态(SOC)的估算精度是影响新能源汽车性能的重要因素之一。传统的安时法由于累积误差较大始终无法满足精确的SOC估计。该文采用基于隐半马尔可夫模型(HSMM)的SOC预测作为安时法的一个补充,使铝空电池后期估计精度可以得到保障。该模型的每个不同状态产生多组观察值,根据各个状态之间的转换概率以及状态驻留时间可以比较准确地预测后期各个状态下的剩余寿命。经过实验仿真验证,与单一的安时法相比,结合HSMM的SOC估计精度在后期有较大提升。

关键词：铝空电池安时法隐半马尔可夫模型荷电状态

不同构型羧甲基茯苓多糖(CMP)抗氧化活性研究

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湖南师范大学自然科学学报 2018年第5期41卷 29-33页

作者：杨焕治刘欣杨岚张城杨中扬彭国平湖南农业大学生物科学与技术学院中国长沙410128 道地药用植物规范化栽培与综合利用湖南省工程实验室中国长沙410128

为探究不同构型羧甲基茯苓多糖(CMP)体外抗氧化活性的"构-效"关系,在不同制备条件下,采取碱液分批提取法,获取不同CMP组分.通过GPC-RI-MALS方法,测定CMP的数均分子量(M_n)、均方根旋转半径(RMS),拟合RMS得到CMP的空间构型图,其斜率对应... 详细信息

为探究不同构型羧甲基茯苓多糖(CMP)体外抗氧化活性的"构-效"关系,在不同制备条件下,采取碱液分批提取法,获取不同CMP组分.通过GPC-RI-MALS方法,测定CMP的数均分子量(M_n)、均方根旋转半径(RMS),拟合RMS得到CMP的空间构型图,其斜率对应CMP的不同空间构型.并对不同CMP组分的还原能力进行检测.结果获得的CMP_1～CMP_(11)不同组分,其重均分子量M_w为1.683×10~5～2.99×10~5. CMP_2和CMP_3构型为无规则卷曲,CMP_6,CMP_7,CMP_9,CMP_(10)及CMP_(11)为类球构型.NaOH浓度0.8 mol/L、反应时间8 h、乙醇体积分数80%条件下制备的CMP_8组分的分子构型斜率为0.37,其还原能力最强(0.702).可知CMP的制备条件决定其空间构型,而空间构型决定其抗氧化活性.类球构型的CMP抗氧化能力强于其他构型CMP组分,无规则卷曲构型的CMP组分抗氧化活性最弱.

关键词：羧甲基茯苓多糖(CMP) 分子构型抗氧化活性

Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou yang Dai Guoyao Yue Yiman Zhang Lulu Li zhong-Zhen Yu Peng Min Hao-Bin Zhang 21 State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

盖挖逆作法在城市道路下建设人防工程中的应用

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山西建筑 2014年第28期40卷 111-112页

作者：杨忠阳山西一建集团有限公司山西太原030012

介绍了盖挖逆作法在城市地下人防工程应用中的工艺流程及操作要点,并对特殊部位提出了有针对性的处理方法,实践证明在地下人防工程采用盖挖逆作法施工,保证了两侧建筑物的稳定和安全,对今后同类工程具有很好的借鉴作用。

关键词：盖挖逆作法结构顶板特殊部位降水暗挖