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Chinese Journal of Chemical Physics 2008年第3期21卷 217-220页

作者： Bo Wu Yan-qiu Chu Zhao-yun Dai chuan-fan ding Physical Chemistry Institute Department of Chemistry Fudan University Shanghai 200433 China Infectious Disease Department Huadong Hospital Shanghai 200040 China

Allergic contact dermatitis is a delayed hypersensitivity reaction, which results from skin exposure to low molecular weight chemicals such as haptens. To clarify the pathogenic mechanism, electrospray ionization mass spectrometry （ESI-MS） and hydrogen/deuterium （H/D） exchange, as well as UV spectroscopy, were applied to determine the interaction between the model protein cytochrome c （cyt c） and the hapten 2,4- dinitro-fiuorobenzene （DNFB）. The ESI-MS results demonstrate that the conformation of cyt c can change from native folded state into partially unfolded state with the increase of DNFB. The equilibrium state H/D exchange followed by ESI-MS further confirms the above results. UV spectroscopy indicates that the strong- field coordination between iron of heme （prosthetic group） and His18 or Met80 of cyt c is not obviously affected by the hapten.

关键词： Interaction Cytochrome c 2 4-dinitro-fluorobenzene ESI-MS

Analytical Modelling and Experiment of Novel Rotary Electro-Mechanical Converter with Negative Feedback Mechanism for 2D Valve

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 162-182页

作者： Bin Meng Mingzhu Dai Chenhang Zhu Chenchen Zhang chuan ding Jian Ruan College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China

The manufacturing of spiral groove structure of two-dimensional valve(2D valve)feedback mechanism has shortcomings of both high cost and *** paper presents a novel configuration of rotary electro-mechanical converter with negative feedback mechanism(REMC-NFM)in order to replace the feedback mechanism of spiral groove and thus reduce cost of valve *** order to rapidly and quantitative evaluate the driving and feedback performance of the REMC-NFM,an analytical model taking leakage flux,edge effect and permeability nonlinearity into account is formulated based on the equivalent magnetic circuit *** the model is properly simplified in order to obtain the optimal pitch *** simulation is used to study the influence of crucial parameters on the performance of REMC-NFM.A prototype of REMC-NFM is designed and machined,and an exclusive experimental platform is *** torque-angle characteristics,torque-displacement characteristics,and magnetic flux density in the working air gap with different excitation currents are *** experimental results are in good agreement with the analytical and FEM simulated results,which verifies the correctness of the analytical *** torque-angle characteristics,the overall torque increases with both current and rotation angle,which reaches about 0.48 N·m with 1.5 A and 1.5°.While for torque-displacement characteristics,the overall torque increases with current yet decrease with armature displacement due to the negative feedback mechanism,which is about 0.16 N·m with 1.5 A and 0.8 ***,experimental results of conventional torque motor are compared with counterparts of REMC-NFM in order to validate the simplified *** research indicates that the REMC-NFM can be potentially used as the electro-mechanical converter for 2D valves in civil servo areas.

关键词： Electro-mechanical converter Magnetic circuit topology Analytical modeling 2D valve

Understanding how heterogeneous agents affect Principal's returns:Perspectives from short-termism and Bayesian learning

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Journal of Management Science and Engineering 2023年第3期8卷 342-368页

作者： chuan ding Yang Li Zhenyu Cui School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China School of Business Stevens Institute of TechnologyHobokenNJ07030USA

We consider a general framework of optimal contract design under the heterogeneity and short-termism of *** research shows that the optimal contract must weigh the agent's information rent,incentive cost,and benefit to overcome the contract's adverse selection and moral *** with higher moral levels were more likely to choose higher effort and lower ***,the principal offers lower incentives and receives more significant *** also extend our model to investigate the benefits of Bayesian ***,we compare the principal's returns in general and learning models and find that the learning contract can bring more profit to the principal。

关键词： Short-termism Bayesian learning Agent heterogeneity Principal-agent model

Constitutive modeling and analysis on high-temperature flow behavior of 25 steel

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Journal of Iron and Steel Research International 2021年第1期28卷 76-85页

作者： Wei Wei Chao-long Yuan Ren-dong Wu Wei Jiao ding-chuan Liang Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

The constitutive relationship is the basis for studying the material processing technology and controlling the quality of *** and models of the plastic flow behavior of materials are often required during the manufacturing ***,establishing constitutive models with high precision and generalization and enriching material database is of great significance for optimizing processing technology and product quality of the *** on the Gleeble thermal compression test results,the essential relationship of 25 steel between the flow stress and thermal–mechanical state variables,such as temperature,strain rate,and strain,is quantitatively discussed for the first *** with the Zener–Hollomon parameter and considering the influence of strain compensation,the constitutive model of 25 steel is built by the hyperbolic-sine equation over the full strain *** the modeling process,the influence of strain on material constants is characterized by polynomial *** selection basis of polynomial order is discussed in-depth,and the inconsistency between calculation accuracy and fitting effect is ***,the accuracy of the model is analyzed,and the generalization and applicability are *** is proved that the developed model can accurately predict the flow behavior of materials in the full strain range.

关键词： Constitutive relationship Flow behavior Plastic deformation Polynomial fitting Generalization

A review of helical carbon materials structure,synthesis and applications

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Rare Metals 2021年第1期40卷 3-19页

作者： ding-chuan Wang Yu Lei Wei Jiao Yi-Fan Liu Chun-Hong Mu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China School of Public Affairs and Law Southwest Jiaotong UniversityChengdu 610031China National Engineering Research Center of Electromagnetic Radiation Control Materials State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054China

The helical structures possess unique physical and chemical properties,such as superelasticity,high specific strength,chirality,and electromagnetic cross-polarization *** the development of nanoscience and nanotechnology,helical structures with various scales have been discovered or synthesized *** them,the helical carbon materials receive much attention around the ***,we present a brief review of the development of helical carbon materials in terms of structures,synthesis techniques and mechanisms,and *** controllable designing of catalysts,carbon sources and reaction parameters plays a key role to optimize the properties of the helical carbon *** the same time,the applications in microwave absorption devices,sensors,catalysts,energy conversions and storage devices,and solar cell are also *** the good chemical and physical properties,helical carbon materials have a good application prospect in many *** potential issues and future opportunities of the helical carbon materials are also proposed.

关键词： Helical carbon materials Coil Synthesis mechanisms Applications

Social network learning efficiency in the principal-agent relationship

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Journal of Management Science and Engineering 2024年第2期9卷 193-219页

作者： chuan ding Yilin Hong Yang Li Peng Liu School of Mathematics Southwestern University of Finance and EconomicsChengdu611130China S.C.Johnson College of Business Cornell UniversityIthacaNY14853USA

Under the bounded rationality assumption,a principal rarely provides an optimal contract to an *** from others is one way to improve such a *** paper studies the efficiency of social network learning(SNL)in the principal–agent *** first introduce the Cobb-Douglas production function into the classic Holmstrom and Milgrom(1987)model with a constant relative risk-averse agent and work out the theoretically optimal *** are then designed to model the SNL process based on profit gaps between contracts in a network of *** the uncertainty of the agent's labor output,we find that the principals can reach a consensus that tends to result in overcompensation compared to the optimal ***,this study examines how network attributes and model parameters impact learning efficiency and posits several summative *** simulation results validate these hypotheses,and we discuss the relevant economic implications of the observed changes in SNL efficiency.

关键词： Simulation Social network learning Principaleagent Reaching consensus Learning efficiency

Drug adulteration analysis based on complexation with cyclodextrin and metal ions using ion mobility spectrometry

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Journal of Pharmaceutical Analysis 2023年第3期13卷 287-295页

作者： Zhigang Liang Huanhuan Wang Fangling Wu Longfei Wang Chenwei Li chuan-Fan ding Department of Thoracic Surgery Ningbo First HospitalNingbo UniversityNingboZhejiang315010China Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province Institute of Mass SpectrometrySchool of Material Science and Chemical EngineeringNingbo UniversityNingboZhejiang315211China

Drug adulteration and contamination are serious threats to human health therefore,their accurate monitoring is very ***(Alp)and theophylline(Thp)are commonly used drugs for the treatment of gout and bronchitis,while their isomers hypoxanthine(Hyt)and theobromine(Thm)have no effect and affect the efficacy of the *** this work,the drug isomers of Alp/Hyt and Thp/Thm are simply mixed withα-,β-,γ-cyclodextrin(CD)and metal ions and separated using trapped ion mobility spectrometry-mass spectrometry(TIMS-MS).TIMS-MS results showed that Alp/Hyt and Thp/Thm isomers could interact with CD and metal ions and form corresponding binary or ternary complexes to achieve their TIMS *** metal ions and CDs showed different separation effect for the isomers,among which Alp and Hyt could be successfully distinguished from the complexes of[Alp/Hyt+γ-CD+Cu–H]^(+)with separation resolution(RP–P)of 1.51;whereas Thp and Thm could be baseline separated by[Thp/Thm+γ-CD+Ca–H]^(+)with RP–P of ***,chemical calculations revealed that the complexes were in the inclusion forms,and microscopic interactions were somewhat different,making their mobility ***,relative and absolute quantification was investigated with an internal standard to determine the precise isomers content,and good linearity(R^(2)>0.99)was ***,the method was applied for the adulteration detection where different drugs and urine were *** addition,due to the advantages of fast speed,simple operation,high sensitivity,and no chromatographic separation required,the proposed method provides an effective strategy for the drug adulteration detection of isomers.

关键词： Drug isomer Adulteration Separation Ion mobility Chemical calculations

Conformation Changes of Enkephalin in Coordination with Pb^(2+) Investigated by Gas Phase Hydrogen/Deuterium Exchange Mass Spectrometry Combined with Theoretical Calculations

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Chemical Research in Chinese Universities 2022年第2期38卷 572-578页

作者： HAN Jiaru WU Fangling YANG Shutong WU Xiaonan TANG Keqi LI Zhenhua ding chuan-Fan Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis of Zhejiang Province Institute of Mass SpectrometrySchool of Material Science and Chemical EngineeringNingbo UniversityNingbo 315211P.R.China Department of Chemistry Fudan UniversityShanghai 200438P.R.China

In this study, the effects of lead ions(Pb^(2+)) on the conformations of leucine encephalin(LE) and methionine encephalin(ME) in gas phase were studied using hydrogen/deuterium exchange mass spectrometry(HDX-MS) and quantum chemistry theoretical calculations at the molecular level. The HDX-MS result revealed that the complexes with the monovalent compounds [LE+Pb–H]+ and [ME+Pb–H]+had a 1:1 stoichiometric ratio, and different HDX reactivates were observed in a follow of [ME+H]+>[LE+H]+>[LE+Pb–H]+> [ME+Pb–H]+. Combining the collision-induced dissociation energies of the complexes and their HDX results, it was found that the more stable the complex, the harder it was for HDX. In addition, the favo-rable conformations of the complexes were obtained by theoretical calculations, revealing that the similar coordination type with diffe-rent bond lengths was obtained. Then, the proton affinity(PA) values of the optimized complexes were calculated to interpret the HDX observations, indicating that the higher the PA values, the more difficult it was for HDX. Overall, the experiments and theoretical calculations revealed that Pb^(2+) could induce conformational changes of LE and ME, and generate ME into a more rigid conformation than LE. The results will prompt further fundamental investigations on the conformational properties of LE/ME in coordination with Pb^(2+).

关键词： Encephalin Pb^(2+) Gas phase-hydrogen/deuterium exchange(HDX) Theoretical calculation ESI-TOF-MS

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基于雷达测量数据的弹箭扰动源最优估计

中国惯性技术学报 2017年第4期25卷 544-549页

作者：丁传炳中国舰船研究设计中心上海201108

为精确计算舰载武器的飞行状态参数,以弹体纵向运动过程为研究对象,推导了包含误差干扰源在内的纵向扰动运动学方程,利用"系数冻结法"及拉普拉斯变换得到解析解,拟合出弹体被动段纵向运动的气动参数公式,采用三坐标雷达测量量作为系统... 详细信息

为精确计算舰载武器的飞行状态参数,以弹体纵向运动过程为研究对象,推导了包含误差干扰源在内的纵向扰动运动学方程,利用"系数冻结法"及拉普拉斯变换得到解析解,拟合出弹体被动段纵向运动的气动参数公式,采用三坐标雷达测量量作为系统量测方程,从而对气动参数误差干扰源进行最优估计。计算结果表明:该算法可以使俯仰操纵力矩系数导数误差的精度稳定在±0.007(°)^(-1)范围内,阻力系数误差的精度趋于±0.025之间;升力系数误差基本稳定在±0.12之间;俯仰力矩系数对攻角的导数偏差精度稳定在±0.011(°)^(-1)之间;俯仰阻尼力矩系数误差的精度收敛于±0.009(°)^(-1)之间,且算法收敛速度快,可为重构高精度的弹道参数提供支撑。

关键词：最优估计纵向运动扰动源雷达

Advancements in our understanding of circular and long non-coding RNAs in spinal cord injury

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Neural Regeneration Research 2022年第11期17卷 2399-2403页

作者： Yan Zhang Ho Jun Yun Yu Ji Eric Cosky Wen-Xiu Zhang Wei Han Yu-chuan ding Central Laboratory Beijing Luhe HospitalCapital Medical UniversityBeijingChina Department of Neurosurgery Wayne State University School of MedicineDetroitMIUSA Department of General Surgery Beijing Luhe HospitalCapital Medical UniversityBeijingChina

Spinal cord injury(SCI),either from trauma or degenerative changes,can res ult in severe disability and impaired quality of *** the cellular processes and molecular mechanisms that underlie SCI is imperative to identifying molecular targets for potential *** studies have shown that non-coding RNAs,including both long non-coding RNAs(lncRNAs)and circular RNAs(circRNAs),regulate various cellular processes in *** this review,we will describe the changes in lncRNA and circRNA expression that occur after SCI and how these changes may be related to SCI *** evidence for the roles of lncRNAs and circRNAs in neuronal cell death and glial cell activation will also be ***,the possibility that lncRNAs and circRNAs are novel modulato rs of SCI pathogenesis will be discussed.

关键词： circular RNAs function long non-coding RNAs neuronal cells neuronal glia pathogenesis regulation spinal cord injury