检索结果-南通市图书馆

Science China Chemistry 2025年

作者： Panke Zhou Yuxing Huang Ziyue Yu Cong Zhang qian chen Yiping Li Chao Lin Xiong chen State Key Laboratory of Photocatalysis on Energy and Environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COFs), namely Py-EDA and Py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/Py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/OFF current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within Py-BDA, thereby further promoting interlayer charge transfer and separation.

关键词：

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

银发经济中备老人群消费特征与发展趋势研究

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 48-58,F0002页

作者：彭希哲陈倩复旦大学老龄研究院上海200433

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较... 详细信息

银发经济已成为我国未来经济持续增长的重要领域,发展银发经济需要从供给和需求两方面同时发力。银发经济有特定的年龄针对性,文本关注银发经济中未老阶段的备老经济。备老人群呈现身体健康状况良好、预期寿命持续延长,文化教育水平较高、消费观念开放包容,互联网普及程度较高、消费个性化、注重悦己等群体特征,具有较强的消费能力和消费意愿,备老人群的消费将为银发经济带来巨大的增量空间。深入理解并满足备老人群的消费需求,对推动供需在更高水平实现良性循环、促进银发经济高质量发展具有重要意义。

关键词：银发经济备老经济高质量发展良性循环消费特征

双阻尼模型调谐质量阻尼器在随机激励下的减震性能研究

在线全文

学校读者我要写书评

暂无评论

Exploiting optical degrees of freedom for information multiplexing in diffractive neural networks

工程力学 2025年第1期42卷 103-115页

作者：向越谭平贺辉陈倩敏广州大学土木工程学院广东广州510006 广州大学工程抗震减震与结构安全教育部重点实验室广东广州510006 湖南工学院土木与建筑工程学院湖南衡阳421002

该文提出黏滞阻尼与滞变阻尼共同作用的双阻尼模型调谐质量阻尼器(Dual Damping Tuned Mass Damper, DD-TMD)，并对白噪声作用下DD-TMD进行减震优化研究。讨论了DD-TMD的构成、优势和应用范围，并总结了DD-TMD的力学机理。提出适用于DD-... 详细信息

该文提出黏滞阻尼与滞变阻尼共同作用的双阻尼模型调谐质量阻尼器(Dual Damping Tuned Mass Damper, DD-TMD)，并对白噪声作用下DD-TMD进行减震优化研究。讨论了DD-TMD的构成、优势和应用范围，并总结了DD-TMD的力学机理。提出适用于DD-TMD的H2优化方法，并通过数值寻优得到了最优参数和基于稳定区域的DD-TMD参数优化方法。此外，通过DD-TMD的H2优化方法进一步得到了DD-TMD的等效附加黏滞阻尼比，为工程设计奠定应用基础。以变摩擦摆式调谐质量阻尼器(Variable Friction Pendulum Tuned Mass Damper, VFP-TMD)为DD-TMD的实际应用算例，通过20条地震波检验所提出的优化方法对地震激励的减震性能影响。结果表明：H2优化下的DD-TMD可以提供与常规黏滞阻尼TMD相当的控制效果。采用DD-TMD可以通过随机理论成功模拟与常摩擦阻尼等效的黏滞阻尼，并为带有初始摩擦的VFP-TMD提供有效可靠的优化设计方法。相较于前人所做的数值寻优方法，按照DD-TMD模型优化的VFP-TMD可以提供更加优异的减震控制效果且阻尼耗能能力提高了16.6%。

关键词：结构减震控制调谐质量阻尼器双阻尼模型 H2优化等效附加黏滞阻尼比

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Light(Science & Applications) 2022年第8期11卷 1639-1642页

作者： Chao Zuo qian chen Smart Computational Imaging Laboratory(SCILab) School of Electronic and Optical EngineeringNanjing University of Science and Technology210094NanjingJiangsu ProvinceChina Smart Computational Imaging Research Institute(SCIRI)of Nanjing University of Science and Technology 210019NanjingJiangsu ProvinceChina Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense 210094NanjingJiangsu ProvinceChina

Exploiting internal degrees of freedom of light, such as polarization, provides efficient ways to scale the capacity of optical diffractive computing, which may ultimately lead to high-throughput, multifunctional all-... 详细信息

关键词： degrees optical networks

Synthesis and Characterization of Cobalt-Carbon Core-Shell Microspheres in Supercritical Carbon Dioxide System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2008年第1期21卷 76-80页

作者： Jun-song Yang qian-wang chen Hefei National Laboratory for Physical Sciences at Microscale Department of Materiab Science andEngineering Department of Chemisto4 University of Science and Technology of China Hefei 230025China

The synthesis of cobalt-carbon core-shell microspheres in supercritical carbon dioxide system was investi- gated. Cobalt-carbon core-shell microspheres with diameter of about 1μm were prepared at 350 ℃ for 12 h in a closed vessel containing an appropriate amount of bis（cyclopentadienyl）cobalt powder and dry ice. Characterization by a variety of techniques, including X-ray powder diffraction, X-ray photoelectron spectroscopy, TransmissiOn electron microscope, Fourier transform infrared spectrum and Raman spectroscopy analysis reveals that each cobalt-carbon core-shell microsphere is made up of an amorphous cobalt core with diameter less than 1 μm and an amorphous carbon shell with thickness of about 200 nm. The possible growth mechanism of cobalt-carbon core-shell microspheres is discussed, based on the pyrolysis of bis（cyclopentadienyl）cobalt in supercritical carbon dioxide and the deposition of carbon or carbon clusters with odd electrons on the surface of magnetic cobalt cores due to magnetic attraction. Magnetic measurements show 141.41 emu/g of saturation magnetization of a typical sample, which is lower than the 168 emu/g of the corresponding metal cobalt bulk material. This is attributed to the considerable mass of the carbon shell and amorphous nature of the magnetic core. Control of magnetism in the cobalt-carbon core-shell microspheres was achieved by annealing treatments.

关键词： Cobalt-carbon core-shell microspheres Supercritical carbon dioxide system

An improved nonlinear onboard adaptive model for aero-engine performance control

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第10期36卷 317-334页

作者： qian chen Hanlin SHENG Tianhong ZHANG Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

The onboard adaptive model can achieve the online real-time estimation of performance parameters that are difficult to measure in a real aero-engine,which is the key to realizing modelbased performance *** must possess satisfactory numerical stability and estimation ***,the positive definiteness of the state covariance matrix may be destroyed in filter estimation because of the existence of some uncertain factors,such as the accumulated measurement error,noise,and disturbance in the strongly nonlinear engine system,inevitably causing divergence of estimates of Cholesky decomposition-based Spherical Unscented Kalman Filter(SUKF).Therefore,this paper proposes an improved SUKF algorithm(iSUKF)and applies it to the performance degradation estimation of the *** to SUKF,the iSUKF mainly replaces the Cholesky decomposition with the Singular Value Decomposition(SVD),which is numerically stable without any strict requirement for the state covariance ***,a correction factor is designed to assess the measurement deviation between the real engine and the nonlinear onboard model to correct the state covariance matrix,thus maintaining better numerical stability of parameters estimated by the ***,an offline correction strategy is also proposed to eliminate the influence of the degradation of unestimated health parameters or the filter’s inadequate estimation of the coupled health *** action effectively promotes the onboard adaptive model’s estimation accuracy concerning the degradation of the engine’real health parameters and its performance ***,the simulation results show that the iSUKF can maintain the numerical stability of the filter’s estimation of health *** with the existing methods,the offline correction strategy improves the estimation accuracy of the iSUKF-based nonlinear onboard adaptive model for the performance parameters of the real engine by more than 50%.The proposed met

关键词： Aero-engine Onboard adaptive model Spherical unscented Kalman filter Parameter estimation iSUKF

Potential role of the protein interactome in translating TCM theory and clinical practice into modern biomedical knowledge

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2024年第5期22卷 385-386页

作者： chen qian FAN Xiaohui Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100China

With the awarding of the 2015 Nobel Prize in Physiology or Medicine to Chinese pharmacologist Tu Youyou,and the significant contributions of traditional Chinese medicine(TCM)for coronavirus disease 2019(COVID-19),TCM has garnered increasing attention and interest *** advanced research progress has been made in the efficacy research,mechanism elucidation and target prediction of TCM in recent years[1].

关键词： Protein interactome Traditional Chinese medicine Therapeutic effectiveness

Transport diffuse interface model for simulation of solid-fluid interaction

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 321-330页

作者： Li LI qian chen Baolin TIAN Institute of Applied Physics and Computational Mathematics

For solid-fluid interaction, one of the phase-density equations in diffuse interface models is degenerated to a "0 = 0" equation when the volume fraction of a certain phase takes the value of zero or unity. This is because the conservative variables in phasedensity equations include volume fractions. The degeneracy can be avoided by adding an artificial quantity of another material into the pure phase. However, nonphysical waves,such as shear waves in fluids, are introduced by the artificial treatment. In this paper,a transport diffuse interface model, which is able to treat zero/unity volume fractions, is presented for solid-fluid interaction. In the proposed model, a new formulation for phase densities is derived, which is unrelated to volume fractions. Consequently, the new model is able to handle zero/unity volume fractions, and nonphysical waves caused by artificial volume fractions are prevented. One-dimensional and two-dimensional numerical tests demonstrate that more accurate results can be obtained by the proposed model.

关键词： solid-fluid interaction diffuse interface model phase-density equation Mie-Gruneisen equation of state(EOS) Eulerian method

Review on article of preoperative prediction in chronic hepatitis B virus patients using spectral computed tomography and machine learning

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第38期30卷 4239-4241页

作者： Yao-qian Yuan qian-qian chen Department of Gastroenterology The First Medical Center of Chinese PLA General HospitalBeijing 100853China

This letter comments on the article that developed and tested a machine learning model that predicts lymphovascular invasion/perineural invasion status by combining clinical indications and spectral computed tomography characteristics *** review the research content,methodology,conclusions,strengths and weaknesses of the study,and introduce follow-up research to this work.

关键词： Gastric cancer Spectral computed tomography Perineural invasion Lympho-vascular invasion Machine learning

Adaptive tracking control of flapping wing micro-air vehicles with averaging theory

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2018年第1期3卷 18-27页

作者： chen qian Yongchun Fang Institute of Robotics and Automatic Information Systems College of Computer and Control Engineering Tianjin 300353People's Republic of China Tianjin Key Laboratory of Intelligent Robotics Nankai University Tianjin 300353 People's Republic of China

An input constrained adaptive tracking controller is designed for flapping micro aerial vehicles, wherein the moving averaging filter is adopted to estimate the averaged states of the system. Specifically, in the outer loop controller, an observer is constructed to estimate the disturbances within the system. Moreover, the constrained thrust is designed to keep the frequency in a proper region so as to meet the requirement of average estimation. Then, a tracking differentiator is used to provide trackable trajectories for the inner loop. Subsequently, a new quaternion- based hybrid attitude tracking controller is designed which successfully deals with high-frequency noises and avoids possible chattering. As supported by mathematical analysis, the proposed control strategy guarantees the uniform ultimate boundedness of the closed-loop system, and it keeps the control torques within the permitted range to meet the application requirement. At last, numerical simulations are carried out to support the validity of the proposed controller, whose results are satisfactory even when the thrust and torques are saturated.

关键词：飞行器跟踪器人工智能发展现状