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Crystallization Behavior of Disproportionately High and Low Molecular Weight PEO Blends

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Chinese Journal of Polymer Science 2014年第9期32卷 1199-1209页

作者： Li Li jun-teng liu Zhong-jie Ren 闫寿科 Department of Chemistry and Chemical Engineering Heze University Beijing Key Laboratory of Membrane Science & State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

The crystallization behavior of PEOs with molecular weight of 1 Ok and 200k as well as their blends was studied in details. The results show that the lower molecular weight PEO crystallizes with faster crystallization rate as judged from a shorter time for completing the crystallization. On the other hand, the higher molecular weight PEO crystallizes at relatively higher temperature, indicating an early start of crystallization compared with the lower molecular weight one. The blends of these two PEOs with different blend ratios always cocrystallize during the cooling processes. It is confirmed that mixing of the 10k PEO with the 200k one is in favor of the crystallization of the system. This is not only demonstrated by the early start of the crystallization at higher crystallization temperature, and also a faster crystal growth of the blend with respect to the 200k PEO. The crystallization of the blends at higher temperature is caused by an early start of nucleation and an increment of nucleus density. This may originate from the density fluctuation of the blend and a reduction in energy barrier for nucleation. Moreover, it is found that the crystallinity of the 1 Ok PEO rich blends increases with increasing concentration of the 10k PEO. This is caused by the solvent effect of the 10k PEO toward the 200k PEO. On the other hand, the crystallinity of the 30/70 （10k/200k） PEO blend is decreased a little bit. This may be a balanced result of the improved crystallization of the 200k PEO at the expense of the high crystallization ability of the 1 Ok PEO.

关键词： PEO Molecular weight Blend Crystallization Morphology.

Modeling of a dynamic dual-input dual-output fast steering mirror system

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1488-1498页

作者： Hong SONG Jia-heng ZHANG Ping YANG Hao-cai HUANG Shu-yue ZHAN teng-jun liu Yi-lu GUO Hang-zhou WANG Hui HUANG Quan-quan MU Mei-fen FANG Ming-yuan YANG Ocean College Zhejiang UniversityZhoushan 316021China School of Digital Media&Design Hangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesJilin 130033China Blue-Science Opto-Electronics Co.Ltd. Hangzhou 310018China Core Tomorrow Science&Technology Co.Ltd. Harbin 150080China

A modeling method is proposed for a dynamic fast steering mirror(FSM) system with dual inputs and dual outputs. A physical model of the FSM system is derived based on first principles, describing the dynamics and coupling between the inputs and outputs of the FSM system. The physical model is then represented in a state-space form. Unknown parameters in the state-space model are identified by the subspace identification algorithm, based on the measured input-output data of the FSM system. The accuracy of the state-space model is evaluated by comparing the model estimates with measurements. The variance-accounted-for value of the state-space model is better than 97%, not only for the modeling data but also for the validation data set, indicating high accuracy of the model. Comparison is also made between the proposed dynamic model and the conventional static model, where improvement in model accuracy is clearly observed. The model identified by the proposed method can be used for optimal controller design for closed-loop FSM systems. The modeling method is also applicable to FSM systems with similar structures.

关键词： Fast steering mirror Dynamic system Input-output coupling,Physical modeling Subspace identification

Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han Jia Tuo liu Yuzhen Yang jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling liu Biao Meng Tao Chen Yu Han jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst Electrocatalysis

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金融法制定中的基本范畴与体系结构研究

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 17-29,F0002页

作者：刘少军中国政法大学民商经济法学院北京102249 中国政法大学金融法研究中心北京102249

党的十八届三中全会以来,党和政府高度重视金融立法和修法工作。全国人大常委会立法工作计划的预备审议项目要求研究包括金融监管制度在内的金融方面的综合性法律,党的二十届三中全会提出制定金融法,是落实党的二十大报告和2023年中央... 详细信息

党的十八届三中全会以来,党和政府高度重视金融立法和修法工作。全国人大常委会立法工作计划的预备审议项目要求研究包括金融监管制度在内的金融方面的综合性法律,党的二十届三中全会提出制定金融法,是落实党的二十大报告和2023年中央金融工作会议精神、实现建设金融强国目标的重要步骤。制定金融法的核心工作是对现行金融法规进行全面整合,实现金融规范和金融监管的全面覆盖。这就需要对金融法的基本范畴进行研究阐释,对其调整的范围,即金融、金融业及其机构、工具、市场、业务、行为等进行严格界定;必须构建逻辑清晰、结构严谨的金融法体系结构,明晰其目标与原则、要素法体系、行业法体系、体例与结构等问题。

关键词：金融的界定金融业界定目标与原则要素法体系行业法体系体例与结构

Sc和Zr对7055合金铸态及热处理态组织和性能的影响

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特种铸造及有色合金 2018年第10期38卷 1130-1133页

作者：陈勇张军滕广标刘崇宇江鸿杰周文标桂林理工大学材料科学与工程学院广西平果百矿高新铝业有限公司百色百矿集团有限公司广西南南铝加工有限公司

在7055合金成分基础上添加0.14%的Zr及0.15%的Sc,获得7055-0.14Zr-0.15Sc合金。对比该合金与7055合金的铸造、均匀化、轧制及T6态的微观组织与力学性能。研究发现,由Zr、Sc添加所形成的初生Al_3(Sc,Zr)相在铸造过程中起到促进非均质形... 详细信息

在7055合金成分基础上添加0.14%的Zr及0.15%的Sc,获得7055-0.14Zr-0.15Sc合金。对比该合金与7055合金的铸造、均匀化、轧制及T6态的微观组织与力学性能。研究发现,由Zr、Sc添加所形成的初生Al_3(Sc,Zr)相在铸造过程中起到促进非均质形核、细化合金组织的作用。均匀化热处理促使纳米Al_3(Sc,Zr)相析出,该相在热变形及固溶时效处理过程中起到钉扎晶界的作用,进而显著地抑制了晶粒粗化。因此,与7055合金相比,7055-0.14Zr-0.15Sc合金具有更高的强度及塑性。

关键词： 7055铝合金钪锆力学性能微观组织

Improvement of decentralized random decrement technique for data processing in wireless sensor network

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Earthquake Engineering and Engineering Vibration 2016年第3期15卷 627-635页

作者： liu Chengyin Xu Chunchuan teng jun School of Civil and Environmental Engineering Harbin Institute of Technology Shenzhen Graduate School Underground Systems Inc. 84 Business Park DriveArmonk

The Random Decrement Technique （RDT）, based on decentralized computing approaches implemented in wireless sensor networks （WSNs）, has shown advantages for modal parameter and data aggregation identification. However, previous studies of RDT-based approaches from ambient vibration data are based on the assumption of a broad-band stochastic process input excitation. The process normally is modeled by filtered white or white noise. In addition, the choice of the triggering condition in RDT is closely related to data communication. In this project, research has been conducted to study the nonstationary white noise excitations as the input to verify the random decrement technique. A local extremum triggering condition is chosen and implemented for the purpose of minimum data communication in a RDT-based distributed computing strategy. Numerical simulation results show that the proposed technique is capable of minimizing the amount of data transmitted over the network with accuracy in modal parameters identification.

关键词： RDT decentralized computing wireless sensor networks nonstationary

Engineering of Fe d-band center in Fe_(3)O_(4)/CeO_(2)hetero-nanoparticles via orbital coupling for high-efficiency oxygen reduction electrocatalysis

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Nano Research 2025年第1期18卷 129-139页

作者： Jiayi liu Jingwen Yin Yingzi Lin Mingxin Pang Huan Pang Songtao Zhang Lin Xu jun Yang Yawen Tang Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023Chin a 2 State Key Laboratory of Multiphase Complex Systems Center of MesoscienceInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China Testing Center Yangzhou UniversityYangzhou 225009China

The deliberate engineering of the d-band center of metal site represents an effective strategy to boost the intrinsic electrocatalytic performance toward the oxygen reduction reaction(ORR).Herein,following a heterointerfaceinduced orbital coupling rationale,we report a judicious design of an efficient ORR electrocatalyst consisting of Fe_(3)O_(4)/CeO_(2)hetero-nanoparticles in-situ encased into N-doped carbon nanofibers(abbreviated as Fe_(3)O_(4)/CeO_(2)@N-CNFs hereafter).The theoretic calculations uncover that the Fe_(3)O_(4)/CeO_(2)heterointerface-triggered orbital coupling can cause the down shift of the d-band center positions of Fe sites,which leads to the weakened chemisorption of oxygenated groups and lowered energy barrier for the potential-determining step,ultimately dramatically boosting the ORR intrinsic *** a consequence,the well-designed Fe_(3)O_(4)/CeO_(2)@N-CNFs display admirable ORR activity with a half-wave potential of 0.84 V and outstanding structural/electrochemical stability in an alkaline electrolyte,surpassing the commercial Pt/C benchmark and a majority of recently reported Fe_(3)O_(4)-based *** encouragingly,the Fe_(3)O_(4)/CeO_(2)@N-CNFsincorporated Zn-air battery outperforms the Pt/C-assembled counterpart with higher power density,larger energy density,and excellent cycling stability,serving as a competent candidate for ORR-involved renewable energy *** study offers an innovative approach for the rational manipulation of the d-band center and interfacial electron behavior of active sites toward the optimization of electrocatalytic performance.

关键词： hetero-nanoparticles electrospinning interfacial engineering orbital coupling oxygen reduction reaction