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Responsive hyperbranched poly(formyl-1,2,3-triazole)s toward quadruple-modal information security protection

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Science China Chemistry 2022年第4期65卷 771-777页

作者： Baixue li Zhen li Kai you Anjun qin Ben Zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesCenter for Aggregation Induced EmissionSouth China University of TechnologyGuangzhou 510640China Shenzhen Institute of Molecular Aggregate Science and Engineering School of Science and EngineeringThe Chinese University of Hong KongShenzhen 518172China Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Foshan Nanhai Guangdong Technology University CNC Equipment Cooperative Innovation Institute Foshan 528225China

Secrecy has received tremendous attention in modern information society. Innovative polymer-based fluorescent materials with multiple mode emission are quite desirable to achieve multistage data security. Herein, a series of soluble and thermally stable hyperbranched poly(formyl-1,2,3-triazole)s(hb-PFTAs) with high molecular weights were facilely prepared by catalyst-free polycycloaddition of aldehyde-activated internal triyne and diazides. Functional moieties of triphenylamine and binaphthyl could be incorporated into the polymers to offer them with unique fluorescence and circular dichroism properties, *** taking advantage of activated ethynyl and aldehyde groups on their peripheries and in the internal branch chains, the hbPFTAs can undergo efficient single-and double-stage post-functionalization. More importantly, based on the remarkable fluorescence responses to hydrazine and hydrochloric acid, the hyperbranched polymers are featured with triple-mode fluorescent patterns and have been applied in quadruple-modal information encryption and storage with enhanced security and density. Collectively, this work not only enriches the structural diversity of the existing triazole-based material library, but also provides new polymeric materials for data and information security application.

关键词： activated internal triyne hyperbranched poly(formyl-1,2,3-triazole)s post-polymerization modification multilevel information security

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苦参植株中总生物碱的分布及含量测定

氨基酸和生物资源 2001年第2期23卷 57-58页

作者：周维仁李优琴薛飞樊磊江苏省农科院饲料食品所南京210014

选用酸性染料络合显色法测定了江苏盱眙产苦参的根、茎、叶、种子等部位中苦参总碱的含量 ,为充分利用苦参全植株提供了一定的依据。

关键词：苦参植株苦参总碱比色测定分布兽用中药

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying liu Bei Peng Xiaoyan Zhou lixia qin lingyan liang Yichen Wei qingping Zhang Xiaocheng li Haixia qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Internal Resonances for Heave, Roll and Pitch Modes of A Spar Platform Considering Wave and Vortex-Induced Loads in the Main Roll Resonance

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China Ocean Engineering 2017年第4期31卷 408-417页

作者： li Wei TANG you-gang liU li-qin li Yan WANG Bin State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China School of Civil Engineering Tianjin University Tianjin 300072 China Coltabomtive Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240 China

We present a study of the nonlinear coupling internal resonance for the heave roll and pitch performance of a spar platform under the wave and vortex-induced loads when the ratio of the frequencies of heave, roll and pitch are approximately 2：1：1. In consideration of varying wet surface, the three DOFs nonlinear coupled equations are established for the spar platform under the effect of the first-order wave loads in the heave and pitch, and vortex-induced loads in the roll. By utilizing the method of multi-scales when the vortex-induced frequency is close to the natural roll frequency, the first-order perturbation solution is obtained analytically and further validated by the numerical integration. Sensitivity analysis is performed to understand the influence of the damping and the internal detuning parameter. Two cases with internal resonance are shown. The first case is that no saturation phenomenon exists under small vortex-induced loads. The first order perturbation solution illustrates that only the vortex-induced frequency motion in roll and the super-harmonic frequency motion in heave are excited. The second case is that the vortex-induced loads are large enough to excite the pitch and a saturation phenomenon in the heave mode follows. The results show that there is no steady response occurrence for some cases. For these cases chaos occurs and large amplitudes response can be induced by the vortex-induced excitation.

关键词： spar platform three DOFs nonlinear equations multiple scales super-harmonic response energy infiltration

Studies on Stochastic Parametric Roll of Ship with Stochastic Averaging Method

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China Ocean Engineering 2020年第2期34卷 289-298页

作者： WANG li-yuan TANG you-gang li Yan ZHANG Jing-chen liU li-qin School of Civil Engineering Tianjin UniversityTianjin 300072China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

The paper studies the parametric stochastic roll motion in the random *** differential equation of the ship parametric roll under random wave is established with considering the nonlinear damping and ship *** sea surface is treated as a narrow-band stochastic process,and the stochastic parametric excitation is studied based on the effective wave *** nonlinear restored arm function obtained from the numerical simulation is expressed as the approximate analytic *** using the stochastic averaging method,the differential equation of motion is transformed into Ito’s stochastic differential *** steady-state probability density function of roll motion is obtained,and the results are validated with the numerical simulation and model test.

关键词： parametric roll random wave stochastic averaging method probability density function

Strong Current-State Opacity Verification of Discrete-Event Systems Modeled With Time Labeled Petri Nets

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 54-68页

作者： Tao qin li Yin Gaiyun liu Naiqi Wu Zhiwu li the Institute of Systems Engineering Macau University of Science and Technology IEEE the School of Electro-Mechanical Engineering Xidian University

This paper addresses the verification of strong currentstate opacity with respect to real-time observations generated from a discrete-event system that is modeled with time labeled Petri nets. The standard current-state opacity cannot completely characterize higher-level security. To ensure the higher-level security requirements of a time-dependent system, we propose a strong version of opacity known as strong current-state opacity. For any path(state-event sequence with time information)π derived from a real-time observation that ends at a secret state, the strong current-state opacity of the real-time observation signifies that there is a non-secret path with the same real-time observation as π. We propose general and non-secret state class graphs, which characterize the general and non-secret states of time-dependent systems, respectively. To capture the observable behavior of non-secret states, a non-secret observer is ***, we develop a structure called a real-time concurrent verifier to verify the strong current-state opacity of time labeled Petri nets. This approach is efficient since the real-time concurrent verifier can be constructed by solving a certain number of linear programming problems.

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The surge-heave-pitch coupling motions of the Φ- type vertical axis wind turbine supported by the truss Spar floating foundation

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Journal of Hydrodynamics 2019年第4期31卷 669-681页

作者： Ying Guo li-qin liu Yan li Chang-shui Xiao you-gang Tang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 China

The motions of the floating vertical axis wind turbine (VAWT) with consideration of the coupling between the aerodynamics and the hydrodynamics are calculated in this paper. The surge-heave-pitch coupling nonlinear equations of the floating VAWT are established. The aerodynamic loads are obtained by applying the double-multiple-stream tube theory with consideration of the dynamic stall and the floating foundation motion. The motion performances of a 5 MW Φ - Darrieus type floating VAWT are studied with its foundation of the Spar type with heave plates. It is shown that the amplitude of the heave motion of the floating VAWT is small when the heave plates are equipped. The effects of the wind and wave loads on the floating VAWT motions are assessed. The results show that the mean values of the surge and the pitch of the floating VAWT are mainly related to the wind loads;the standard deviations of the surge, the heave, and the pitch are mainly related to the wave loads. In the regular wave cases, the frequencies of the surge, the heave and the pitch are dominated by the wave frequencies, and the components of the 2P responses (caused by the aerodynamic loads) of the pitch are small. The 2P responses of the pitch are more significant in the irregular wave cases as compared with those in the regular wave cases.

关键词： Floating VAWT truss Spar floating foundation surge-heave-pitch motions aerodynamics regular waves irregular waves

Time-frequency analysis of internal waves generated by a towed and self-propelled submerged body model

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Journal of Hydrodynamics 2023年第6期35卷 1191-1207页

作者： Yu-hang li Fei-yu Chen li-ping qin Ke Chen Yun-xiang you Zhengzhou Electromechanical Engineering Research Institute Zhengzhou450015China Henan Key Laboratory of Underwater Intelligence Equipment Zhengzhou450015China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversityShanghai200240China

The spectrogram,based on a short-time Fourier transform,can visualize the time-dependent frequency spectrum of waves and is easy to *** time-frequency analysis method provides crucial information about waves generated by moving vessels and has been utilized to analyze Kelvin ship waves and internal *** further study the internal waves induced by a submerged body,an experiment is conducted for the towed and self-propelled SUBOFF model in a stratified *** internal wave elevation signals are captured using electronic conductivity *** with the calculation results of theoretical model,the high-frequency component of internal waves is *** high-frequency component has the exact same characteristics in both the towed and self-propelled model experiment and is consistent with the theoretical results for all Froude ***,this component is composed mainly of lee *** spectral characteristics identification,a low-frequency component is discovered in the spectrogram in addition to the lee wave *** intensity of the low-frequency component is tightly related to the vortex structure behind the submerged *** vortex structure depends on the net momentum imparted by the submerged ***,this component is composed mainly of wake waves induced by the vortex structure.

关键词： Stratified fluid internal waves submerged body experimental study time-frequency analysis

基于空中计算CoMAC架构的不同计算场景叠加符号判决算法

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 61-70页

作者：秦晓卫周子涵陈力中国科学技术大学信息科学技术学院安徽合肥230027

本文研究不同场景下基于空中计算的多址信道计算(CoMAC)架构的覆盖符号决策算法。首先,从理论上分析了XOR、ADD、MOD三种场景中加性高斯白噪声(AWGN)多址接入信道下叠加符号的概率密度分布,提出了一种基于先验概率的最优门限判决策略。... 详细信息

本文研究不同场景下基于空中计算的多址信道计算(CoMAC)架构的覆盖符号决策算法。首先,从理论上分析了XOR、ADD、MOD三种场景中加性高斯白噪声(AWGN)多址接入信道下叠加符号的概率密度分布,提出了一种基于先验概率的最优门限判决策略。其次,推导了系统最优门限及对应误码率的理论表达式。最后,通过仿真验证了不同信噪比、传感器节点个数及先验概率对于该门限判决方案的鲁棒性和可靠性的影响。与通信计算相分离的传统方案相比,空中计算判决方案具有更好的检测性能,为多址接入信道下的信号识别提供了新的参考方案。

关键词：空中计算多址接入信道最优门限判决检测性能