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噻吩酰亚胺衍生物二阶非线性光学性质的DFT研究

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原子与分子物理学报 2025年第1期42卷 20-28页

作者：蔺彬彬闫慧君哈尔滨学院食品工程学院化学系哈尔滨150086

采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增... 详细信息

采用密度泛函理论(DFT)CAM-B3LYP方法,计算研究了12个设计的噻吩酰亚胺衍生物的电子光谱和二阶非线性光学性质.结果表明,此类化合物有较大的第一超极化率β_(tot)值和β_(vec)值,且β_(tot)值和β_(vec)值随引入氰基数目的增加而显著增大.给/吸电子基团引起的电荷转移变化对体系β_(tot)值和β_(vec)值的影响大于分子六元杂环中N杂原子位置变化对其影响.

关键词：噻吩酰亚胺衍生物密度泛函理论二阶非线性光学性质电子光谱

Strip width spread prediction in rough rolling process based on mechanism modeling and optimization

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Journal of Iron and Steel Research International 2023年第12期30卷 2416-2424页

作者： yan-jiu Zhong Jing-cheng Wang Jia-hui xu jun Rao Department of Automation Key Laboratory of System Control and Information ProcessingShanghai Jiao Tong UniversityShanghai 200240China

Aiming at the problems of low accuracy and poor robustness that existed in the current hot rolling strip width spread model,an improved strip spread prediction model based on a material forming mechanism and Bayesian optimized adaptive differential evolution algorithm(BADE)was *** first,we improved the original spread mechanism model by adding the weight and bias term to enhance the model robustness based on rolling ***,the BADE algorithm was proposed to optimize the improved spread mechanism *** optimization algorithm is based on a novel adaptive differential evolution algorithm,which can effectively achieve the global optimal ***,the prediction performances of five machine learning algorithms were compared in *** results show that the prediction accuracy of the improved spread model is obviously better than that of the machine learning algorithms,which proves the effectiveness of the proposed method.

关键词： Hot rolling Width spread prediction Bayesian optimization:Adaptive differential evolution Parameter optimization

THE STUDY ON A KIND OF CONTROL SYSTEM WITH NONLINEAR PARABOLIC DISTRIBUTED PARAMETERS

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Applied Mathematics and Mechanics(English Edition) 2002年第2期23卷 178-186页

作者： ZHOU Jian-jun(周建军) xu yan-hou(徐燕侯) State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei230026 P R China Department of Mechanic Engineering University of Science and Technology of China Hefei230026 P R China

The modelling of one kind of nonlinear parabolic distributed parameter control system with moving boundary, which had extensive applications was presented, Two methods were used to investigate the basic characteristics of the system: I) transforming the system it? the variable domain into that in the fixed domain; 2) transforming the distributed parameter system into the lumped parameter system. It is found that there are two critical values for the control variable : the larger one determines whether or not the boundary would move, while the smaller one determines whether or not the boundary, would atop automatically. For one-dimensional system of planar, cylindrical and spherical cases the definite solution problem can be expressed as a unified form. By means of the computer simulation the open-loop control system and close-cycle feedback control system have been investigated. Numerical results agree well with theoretical results. The computer simulation shows that the system is well posed, stable, measurable and controllable.

关键词： distributed parameter control system nonlinear moving boundary stability measurability controllability

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水性醇酸树脂及其氨基烤漆的研制

现代涂料与涂装 2016年第10期19卷 8-10页

作者：肖菲贾雪艳孙学军许玉霞西北永新涂料有限公司兰州730046

以豆油酸、邻苯二甲酸酐、三羟甲基丙烷、偏苯三酸酐为基本原料制备水性醇酸树脂,然后经中和剂中和后,搭配水性氨基树脂制备了性能优异的水性醇酸氨基烤漆,并对影响树脂和漆膜性能的因素进行了探讨。

关键词：水性醇酸树脂醇酸氨基烤漆烘烤漆

A quasi-isentropic model of a cylinder driven by aluminized explosives based on characteristic line analysis

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Defence Technology（防务技术） 2022年第11期18卷 1979-1999页

作者： Hong-fu Wang yan Liu Fan Bai jun-bo yan xu Li Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum(Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed,and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction(diffusion and kinetic) between the Al powder and the detonation products;the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.

关键词： Aluminized explosives Cylinder experiments Quasi-isentropic model Characteristic line analysis Reaction degree of Al powder Physical parameters of detonation products

Bayesian Inference of Nucleus Resonance and Neutron Skin

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原子能科学技术 2023年第4期57卷 729-742页

作者： xu jun School of Physics Science and Engineering Tongji UniversityShanghai 200092China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

In this proceeding,some highlight results on the constraints of the nuclear matter equation of state(EOS)from the data of nucleus resonance and neutron-skin thickness using the Bayesian approach based on the Skyrme-Hartree-Fock model and its extension have been ***,the anti-correlation and positive correlations between the slope parameter and the value of the symmetry energy at the saturation density under the constraint of the neutron-skin thickness and the isovector giant dipole resonance have been discussed ***’s shown that the Bayesian analysis can help to find a compromise for the“PREXII puzzle”and the“soft Tin puzzle”.The possible modifications on the constraints of lower-order EOS parameters as well as the relevant correlation when higher-order EOS parameters are incorporated as independent variables have been further *** a given model and parameter space,the Bayesian approach serves as a good analysis tool suitable for multi-messengers versus multi-variables,and is helpful for constraining quantitatively the model parameters as well as their correlations.

关键词： Bayesian inference nuclear matter equation of state nucleus resonance neutron-skin thickness

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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加入WTO后我国体育教育面临的机遇与挑战

体育科学研究 2004年第1期8卷 44-46页

作者：黄彦军徐凤琴商丘师范学院体育系河南商丘476000

运用文献研究与逻辑分析等方法,描述、分析了我国加入WTO后体育教育所受的影响,探讨了体育教育所处的环境与现状,对强项、弱项、机遇、威胁4个方面进行了客观分析。进而提出了我国体育教育应对措施和改革思路。

关键词：中国体育教育入世教育改革人文精神人才培养模式学术交流

Facile Synthesis of Stable MO2N Nanobelts with High Catalytic Activity for Ammonia Decomposition

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Chinese Journal of Chemistry 2019年第4期37卷 364-372页

作者： jun xu Han yan Zhao Jin Chun-Jiang Jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong 250100China

In the present work,high quality γ-Mo2N catalysts for ammonia decomposition were successfully synthesized via temperature programmed nitridation of α-MoO3 *** optimal conditions for the synthesis of MoO3 precursors were obtained by using the orthogonal experimental *** MoO3 precursors and the corresponding fresh and used Mo2N catalysts were characterized by various characterization techniques,including transmission electron microscopy,X-ray diffraction and N2 ***,temperature-programmed desorption by N2 or NH3 and X-ray photoelectron spectroscopy analysis were performed to better understand the chemical properties of Mo2N *** results revealed that Mo2N catalyst has good NH3 adsorption ability and facilitates the dissociation adsorption of ***,the morphology and structure of Mo2N catalysts well maintained after the ***,among the three transition metal nitrides(Mo2N,W2N and VN)and some Mo-based catalysts previously reported,Mo2N catalysts showed very high activity and *** 94% con version of NH3 could be reached at 550 ℃ with the gas hourly space velocity of 22 000 cm^3-gcat^-1·h^-1 and no obvious deactivation was observed during a 72 h test.

关键词： Stable MO2N Nanobelts High Catalytic Activity Ammonia Decomposition