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通信延时环境下异质网联车辆队列非线性纵向控制

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自动化学报 2021年第12期47卷 2841-2856页

作者：李永福何昌鹏朱浩郑太雄重庆邮电大学自动化学院智能空地协同控制重庆市高校重点实验室重庆400065

针对通信延时环境下的异质车辆队列控制问题,本文提出了一种基于三阶模型的分布式非线性车辆队列纵向控制器.首先,基于三阶动力学模型描述了车辆的异质特性.考虑车辆跟驰行为以及异质通信延时,提出一种通信延时环境下的异质车辆队列非... 详细信息

针对通信延时环境下的异质车辆队列控制问题,本文提出了一种基于三阶模型的分布式非线性车辆队列纵向控制器.首先,基于三阶动力学模型描述了车辆的异质特性.考虑车辆跟驰行为以及异质通信延时,提出一种通信延时环境下的异质车辆队列非线性控制器.所提控制器不仅可以在通信延时以及车辆异质特性的影响下实现队列中车辆的位置、速度以及加速度的一致性,而且可以有效避免负的车辆间距和不合理的加/减速度,保证车辆的运动行为符合交通流理论.然后,利用Lyapunov-Krasovskii定理对车辆队列的稳定性进行分析,得出车辆队列的稳定性条件和通信延时上界.最后,所提控制器的有效性和稳定性通过数值仿真得到验证.

关键词：通信延时异质车辆队列非线性控制一致性策略车辆跟驰行为

Label-free fluorescent strategy for sensitive detection of tetracycline based on triple-helix molecular switch and G-quadruplex

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Chinese Chemical Letters 2017年第7期28卷 1380-1384页

作者： Tian-Xiao Chen Feng Ning Hai-Sheng liu Ke-Feng Wu Wei li chang-Bei Ma School of Chemistry and Biological Engineering Changsha University of Science and Technology State Key Laboratory of Medical Genetics & School of life Sciences Central South University

In this assay, a label-free fluorescent sensing platform based on triple-helix molecular switch（THMS） and G-quadruplex was developed for the detection of tetracycline. We demonstrated this approach by using THMS, which consists of a central section with a shortened 8-mer aptamer sequence with high affinity to tetracycline and flanked by two arm segments. G-rich oligonucleotide can specifically bind to thioflavin T（Th T） as a signal transduction probe（STP）. In the absence of tetracycline, THMS remains stable, the fluorescence of background is low. By the addition of target tetracycline, the aptamer-target binding results in the formation of a structured aptamer-target complex, which disassembles the THMS and releases the STP. The free STP self-assembles into G-quadruplex and specifically binds to Th T which generates a obvious fluorescence enhancement. Using the triple-helix molecular switch, the developed aptamer-based fluorescent sensing platform showed a linear relationship with the concentration of tetracycline ranging from 0.2 to 20.0 nmol/L. The detection limit of tetracycline was determined to be970.0 pmol/L. The assay avoids complicated modifications or chemical labeling, making it simple and cost-effective. So, it is expected that this aptamer-based fluorescent assay could be extensively applied in the field of food safety inspection.

关键词： Tetracycline Aptamer Label-free Triple-helix molecular switch G-quadruplex Thioflavin T

Recombination and Mutation of a New Chinese Strain of HP-PRRSV SCMY2023

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Journal of Biosciences and Medicines 2025年第1期13卷 338-358页

作者： Xianchang Zhu Wenhui liu Yang Xia Zhaoxia Yang Qian Lei Yi Zhang Bo Zhang Jida li Institute of Zoonosis College of Public Health Zunyi Medical University Zunyi China Wound Treatment Center Zouping Peoples Hospital Zouping China Department of Medicine Southwest Guizhou Vocational and Technical College Xingyi China Yebio Bioengineering Co. Ltd. of Qingdao Qingdao China Key Laboratory of Maternal & Child Health and Exposure Science of Guizhou Higher Education Institutes Zunyi China

In this study, RT-PCR was performed on lung tissue samples from sick pigs in a suspected outbreak of porcine reproductive and respiratory syndrome (PRRS) at a pig farm in Mianyang City, Sichuan Province, China. Positive samples were inoculated into Marc-145 cells to observe lesions. The Marc-145 cells with cytopathic lesions were identified by indirect immunofluorescence. The whole genome sequences of the isolated and purified strains were amplified by RT-PCR and analyzed for homology and genetic evolution. A strain of porcine reproductive and respiratory syndrome virus (PRRSV), named SCMY2023 (GenBank No. PQ179742), was successfully isolated. SCMY2023 has a genome length of 15,321 base pairs (without a poly A tail). Nucleotide and amino acid homology analyses suggest that this strain belongs to lineage 8, a variant of the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) prevalent in China. Recombination and genetic evolution analyses indicate that this isolate is a PRRSV variant that recombined with HuN-ZZ (lineage 8, 98.79% homology) on the backbone of the SCSN2020 strain (lineage 8, 99.35% homology) in the recombination region from 4407 to 13,107 nucleotides (ORF1a to ORF3). In-depth study of the genetic recombination of this isolate can provide a reference for the prevention and control of PRRS.

关键词： PRRSV Isolation and Identification Recombinant Virus Prevention and Control Strategy

Effect of Different Aging Processes on the Microstructure and Mechanical Properties of a Novel Al–Cu–li Alloy

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Journal of Materials Science & Technology 2016年第10期32卷 1049-1053页

作者： Hongying li Desheng Huang Wei Kang Jiaojiao liu Yangxun Ou Dewang li School of Materials Science and Engineering Central South University Key Laboratory of Non-ferrous Materials Ministry of Education Central South University

The effects of different aging processes on the microstructure and mechanical properties of a novel Al-Cu-li alloy have been investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It is found that the tensile properties of a novel Al-Cu-li alloy are sensitive to aging processes, which correspond to different microstructures. σ（Al_5Cu_6Mg_2） and T_1（Al_2Culi） phases are the major precipitates for the alloy in T6 aging condition（165 ℃/60 h）. After duplex aging condition（150 ℃/24 h ＋ 180 ℃/12 h）, σ, θ＇（Al_2Cu） and T_1 phases are detected. Only the T_1 phases can be found in the T8 state alloy（6% pre-strain＋135 ℃/60 h）. The failure modes of alloy in T6 and duplex aging conditions are dimple-intergranular fracture, while typical quasi-cleavage fracture in T8 condition.

关键词： Al-Cu-li alloy Aging process Microstructure Mechanical properties

Self-assembled liquid crystal architectures for soft matter photonics

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light(Science & Applications) 2022年第12期11卷 2849-2872页

作者： ling-ling Ma Chao-Yi li Jin-Tao Pan Yue-E.Ji chang Jiang Ren Zheng Ze-Yu Wang Yu Wang Bing-Xiang li Yan-Qing Lu National Laboratory of Solid State Microstructures Key Laboratory of Intelligent Optical Sensing and ManipulationCollege of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Self-assembled architectures of soft matter have fascinated scientists for centuries due to their unique physical properties originated from controllable orientational and/or positional orders,and diverse optic and photonic *** one could know how to design,fabricate,and manipulate these optical microstructures in soft matter systems,such as liquid crystals(LCs),that would open new opportunities in both scientific research and practical applications,such as the interaction between light and soft matter,the intrinsic assembly of the topological patterns,and the multidimensional control of the light(polarization,phase,spatial distribution,propagation direction).Here,we summarize recent progresses in self-assembled optical architectures in typical thermotropic LCs and bio-based lyotropic *** briefly introducing the basic definitions and properties of the materials,we present the manipulation schemes of various LC microstructures,especially the topological and topographic *** work further illustrates external-stimuli-enabled dynamic controllability of self-assembled optical structures of these soft materials,and demonstrates several emerging ***,we discuss the challenges and opportunities of these materials towards soft matter photonics,and envision future perspectives in this field.

关键词： architectures topological originated

Particle size distribution of coal and gangue after impact-crush separation

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Journal of Central South University 2017年第6期24卷 1252-1262页

作者： YANG Dao-long li Jian-ping DU chang-long ZHENG Ke-hong liU Song-yong School of Mechatronic Engineering China University of Mining & Technology College of Mines and Earth Sciences University of Utah

Based on the separation and backfilling system of coal and gangue, the mineral material impact experiments were conducted utilizing the hardness difference between coal and gangue according to the uniaxial compression experiments. The broken coal and gangue particles were collected and screened by different size meshes. The particle size distributions of coal and gangue under different impact velocities were researched according to the Rosin-Rammler distribution. The relationships between separation indicators and impact velocities were discussed. It is found from experiments that there is a fully broken boundary of coal material. The experimental results indicate that the Rosin-Rammler distribution could accurately describe the particle size distribution of broken coal and gangue under different impact velocities, and there is a minimum overlap region when the impact velocity is 12.10 m/s which leads to the minimum mixed degree of coal and gangue, and consequently the benefit of coal and gangue separation.

关键词： Rosin-Rammler distribution impact crush separation indicator coal and gangue separation and backfilling system

Donor-acceptor(D-A)terpolymers based on alkyl-DPP and t-BocDPP moieties for polymer solar cells

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Chinese Chemical Letters 2017年第12期28卷 2223-2226页

作者： Fateh Ullah Sun Qian Weitao Yang Muhammad Naeem Shah Zhongqiang Zhang Hongzheng Chen chang-Zhi li MOE Key Laboratory of Macromolecular Synthesis and Functionalization State Key Laboratory of Silicon MaterialsDepartment of Polymer Science andEngineeringZhejiang UniversityHangzhou 310027China

A series of low band gap terpolymers based on 4,8-bis（5-（2-ethylhexyl）thiophen-2-yl）benzo[l,2-b：4,5- b＇]dithiophene （BDTr） and diketopyrrolopyrrole （DPP） with varied solubilizing groups （i.e., tert- butoxycarbonyl, t-Boc and 2-octyldodecyl） are developed as electron donors for bulk heterojunction （BHJ） polymer solar cells （PSCs）. The results reveal that the one with 50% t-Boc concentration （P3） performs better than the other terpolymers used in this study in conventional PSC devices with a power conversion efficiency of 2.92%.

关键词： Conjugated polymerOrganic semiconductorPolymer solar cellsBulk heterojunctionDiketopyrrolopyrrole

Boosting the photodynamic therapy efficiency with a mitochondria-targeted nanophotosensitizer

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Chinese Chemical Letters 2019年第6期30卷 1293-1296页

作者： limin Yang Peng Gao Yuanlei Huang Xiao Lu Qian chang Wei Pan Na li Bo Tang College of Chemistry Chemical Engineering and Materials Science Key Laboratory of Molecular and Nano Probes Ministry of Education Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong Institute of Molecular and Nano Science Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals Shandong Normal University

Photodynamic therapy (PDT) is an attractive clinical technique for cancer treatment. However, the poor solubility and weak cellular internalization of the molecule-photosensitizers, as well as the exceedingly short lifetime and limited diffusion distance of the generated reactive oxygen species (ROS) in cytoplasm directly restricted the therapeutic efficiency of conventional PDT. In this study, we proposed a facile strategy for improving PDT of cancer based on a mitochondria-targeted nanophotosensitizer. The molecule-photosensitizer chlorin e6 was covalently attached on the internal and external surfaces of the mesoporous silica nanoparticles. Then, the triphenylphosphonium was anchored on the nanoparticles for selectively targeting mitochondria. When irradiated with laser, the nanophotosensitizer can generate a large amount of ROS in mitochondria, thus causing the mitochondrial dysfunction and irreversible cell apoptosis. In vitro and in vivo studies demonstrated that the nanophotosensitizer could boost the treatment efficiency against cancer cells and xenograft tumor models.

关键词： Mitochondria Nanophotosensitizer Photodynamic therapy Reactive oxygen species Enhanced treatment efficiency

Effect of exit location on flow of mice under emergency condition

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Chinese Physics B 2019年第1期28卷 290-299页

作者： Teng Zhang Shen-Shi Huang Xue-lin Zhang Shou-Xiang Lu chang-Hai li State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China School of Civil Engineering Chongqing Three Gorges UniversityChongqing 404000China

The evacuation of crowds in a building has always emerged as a vital issue in many accidents. The geometrical structure of a room, especially the exit design has a great influence on crowd evacuation under emergency conditions. In this paper, the effect of exit location of a room on crowd evacuation in an emergency is investigated with mice. Two different exits are set in a rectangular chamber. One is located in the middle of a wall(middle-exit) and the other is at the corner of the chamber(corner-exit). Arching and clogging are observed in the flow of mice. The result based on the escape trajectories of mice shows a dynamic balance in the arch near the exit wherever the exit is located. We demonstrate that the occupant position in the arch has an effect on the escape sequence of mice. At a low stimulation level, the narrow middle-exit is more effective in increasing the flow rate of mice than the narrow corner-exit. However, the opposite result appears when the exit becomes wider. At a high stimulation level, the effect of exit location on flow of mice tends to be weakened. The results suggest that the specific level of stimulation needs to be taken into account when optimizing the evacuation efficiency of a crowd through the geometrical structure of a room.

关键词： exit location evacuation mice stimulation level