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The determination of poly-malic-acid in the fermentation broth of ***

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The determination of poly-malic-acid in the fermentation bro...

2017年浙江省微生物学会青年论坛——微生物与健康专题研讨会

作者： Fangcheng Qiu danfeng zhou Peilian Wei School of Biological and Chemical Engineering Zhejiang University of Science and Technology Zhejiang Provincial Key Laboratory for Chemical and Biological Processing Technology of Farm Products

Poly-malic-acid(PMLA) is a water-soluble polymer formed by the interaction of malic acid *** its unique properties,including high water solubility,biocompatibility and biodegradability,PMA has attracted increasing attention in the biomedical,cosmetics,and food packaging *** can be produced by chemical synthesis and microbial *** fermentation with Aureobasidium pullulans has been the research focus in recent *** amount of PMLA can not be determined directly,it be detected by measure the amount of malic acid after *** for the determination of malic acid,HPLC and spectrophotometric method are usually *** is not widely used because of the requirement of high-cost instruments,and spectrophotometric method is usually not accurate or even can’t be used because of the disturbance of the colored substances produced in the fermentation broth of *** our study a new method for determining of PLMA was established,which is to precipitate the PMLA by ethanol to eliminate the disturbance of colored substance in the broth and then determined by spectrophotometric *** results showed PLMA can be precipitated almost completely with a volume ratio of 1:2.8(broth:ethanol),which was hydrolyzed and determined by spectrophotometric method,the results were very similar with that of *** method can be used to determine the amount of PLMA in fermentation broth of *** of HPLC.

关键词： Aureobasidium pullulans Poly-malic-acid Spectrophotometric method Determination

Magnetic flux feedback strategy to suppress the gap fluctuation of Low speed maglev train caused by track steps

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Magnetic flux feedback strategy to suppress the gap fluctuat...

第37届中国控制会议

作者： YaJian Li PeiChang Yu danfeng zhou Jie Li College of Intelligence Science and Engineering National University of Defense Technology

Magnetically levitated（maglev） train achieves non-contact operation by maintaining a constant suspension gap between the electromagnet and the *** gap is generally 8-10 *** a small suspension gap makes a limited range of the suspension gap,which affects the riding comfort and stability of the *** exits rough suspension gap fluctuation while low speed maglev train running through some track *** electromagnet may hit the track under some severe conditions,which makes loud noise and weakens the riding *** this paper,in order to suppress the gap fluctuation caused by track steps,we propose a linearized coupled model of the suspension module and the *** analysis shows that the differences between the suspension gap signals and mean gap signals of the two suspension points lead to the large fluctuation of the rear suspension *** order to solve this problem,we propose a control strategy using feedback of magnetic flux *** simulations and experiment results show that the strategy can reduce the fluctuation amplitude of the suspension gap and weaken the difference of the gap response between the front and rear suspension points.

关键词： low speed maglev train flux feedback track steps

An Approach to Reduce Vibration of the Levitation System when the Urban Maglev Train is Traveling

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An Approach to Reduce Vibration of the Levitation System whe...

第37届中国控制会议

作者： danfeng zhou Peichagn Yu Jie Li Lianchun Wang National University of Defense Technology State Key Laboratory of Functional Materials for Informatic Shanghai Institute of Microsystem and Information TechnologyChinese Academy of Sciences

The structure of the levitation module in an urban maglev train greatly affects the dynamics of the levitation systems under track irregularities,but this problem has not gained enough attention in the previous studies of maglev train/guideway interaction *** paper tries to reveal the dynamic behaviors of the levitation module when the maglev train is *** analysis indicates that due to the structural configuration of the levitation module,the levitation system is sensitive to short wave track irregularities,and that the dynamic response of the levitation system does not increase monotonously with train ***,under poor track conditions,medium train speed would cause most severe gap *** analysis also well interprets the phenomenon that in a levitation module,the gap deviation of the rear levitation unit is generally stronger than the front levitation *** reduce gap vibration,a solution by rearranging the gap sensors of the levitation module is proposed,which shows a good prospect to enhance the dynamic performance of the levitation system.

关键词： maglev levitation module vibration track irregularity

ALGORITHMS AND ARCHITECTURE IMPLEMENTATIONS OF MIMO OFDM BASEBAND RECEIVER BASED ON THE SIMD DSP CORE

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Journal of Electronics(China) 2006年第5期23卷 763-768页

作者： Hao Xuefei Chen Jie Zhao danfeng zhou Chaoxian SOC Laboratory Institute of Microelectronics Chinese Academy of Sciences Beijng 100029 China Information and Communication Engineering College Harbin Engineering University Harbin 150001 China

This letter presents a programmable single-chip architecture for Multi-lnput and Multi-Output （M1MO） OFDM baseband receiver. The architecture comprises a Single Instruction Multiple Data （SIMD） DSP core and three coprocessors that are used for synchronization, FFT and channel decoder. In this MIMO OFDM system, the Zero Correlation Zone （ZCZ） code is used as the synchronization word preamble of packet in the physical layer in order to avoid the interference from other transmitting antennas. Furthermore, a simple channel estimation algorithm is proposed which is appropriate tbr the SIMD DSP computation.

关键词： Multi-Input and Multi-Output (MIMO) OFDM Baseband receiver Zero Correlation Zone (ZCZ) code Single Instruction Multiple Data (SIMD) DSP

Integral Backstepping and Lyapunov Calm Control Design for Magnetic Levitation System

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Integral Backstepping and Lyapunov Calm Control Design for M...

第40届中国控制会议

作者： Yichuan Wang danfeng zhou Jie Li Mengxiao Song Qing Yang College of Intelligence Science and Technology National University of Defense Technology

Aiming at the problem of maglev train passing through the track joints,this paper proposes a Lyapunov-based backstepping controller for Magnetic Levitation ***,the theoretical model of the maglev system is,and then,the theoretical formulae of the backstepping controller is deduced;to achieve rapid current response,a current loop feedback is ***,a numerical simulation is carried out,and the simulation results show that the backstepping controller is not only simpler in design,but also faster in ***,the designed controller is verified by experiments in the existing maglev *** experimental results show that compared with the traditional PID controller,the backstepping method has a smaller overshoot and a faster response speed when dealing with the problem of a maglev train passing through the track ***,it is more adaptable to external disturbances.

关键词： Maglev Backstepping Track Irregular Anti-interference

Research on Maglev Train-Steel Beam Coupling Vibration Suppression Strategy Based on Flux Derivative Feedback

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Research on Maglev Train-Steel Beam Coupling Vibration Suppr...

第三十九届中国控制会议

作者： Lianchun Wang danfeng zhou Peichang Yu Qiang Chen Jie Li Jinhui Li College of Intelligence Science and Technology National University of Defense Technology

With the continuous expansion of commercial applications of low-medium speed maglev train, the problem of coupled vibration still exists under specific operating conditions, which requires us to pay more urgent attention. This article focuses on the coupling vibration of maglev train-steel beam. When coupling vibration occurs, corresponding measures must be taken to suppress the vibration. This paper considers the suppression method of maglev train-steel beam coupling vibration from the perspective of suspension control. Considering the correlation between the levitation force and the magnetic flux, the introduction of the magnetic flux derivative feedback can adjust the phase of the levitation force, which is beneficial to the suppression of the maglev train-steel beam coupling vibration. This paper will first analyze the stability of the coupled system model based on magnetic flux feedback, and then discuss the vibration suppression strategy based on the magnetic loop feedback control algorithm.

关键词： Maglev Magnetic Flux Suppression Strategy Vibration

磁浮列车-桥梁耦合自激振动机理分析与仿真验证

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振动与冲击 2017年第18期36卷 13-19,55页

作者：王连春李金辉周丹峰李杰国防科学技术大学机电工程与自动化学院长沙410073 近地面探测与感知技术重点实验室江苏无锡214035

当磁浮列车静止悬浮在某段桥梁上时,磁浮列车的电磁铁和桥梁会同时出现大幅垂向振动,这种现象被称为磁浮列车-桥梁耦合自激振动;目前国内外对于该问题的研究不够完善,振动产生的机理认识也不够清楚;同时在工程上,车-桥梁耦合自激振动问... 详细信息

当磁浮列车静止悬浮在某段桥梁上时,磁浮列车的电磁铁和桥梁会同时出现大幅垂向振动,这种现象被称为磁浮列车-桥梁耦合自激振动;目前国内外对于该问题的研究不够完善,振动产生的机理认识也不够清楚;同时在工程上,车-桥梁耦合自激振动问题仍未得到很好解决。为此,从三个不同角度来分析车-桥梁耦合自激振动的基本原理;首先建立了单悬浮点-弹性桥梁简化的耦合模型,并基于此最小耦合模型,从能量传递的角度阐述了自激振动的机理,并指出悬浮系统在特定频段的有源性是导致自激振动产生的根本原因;其次,将桥梁子系统作为整个耦合系统的前向通道,将悬浮子系统视为耦合系统的反馈通道,由此从耦合系统的特征多项式的角度分析了自激振动的机理;最后根据系统开环传递函数,利用稳定性判据分析了自激振动的基本原理。基于上述分析,得出了四个有效结论,为认识并解决自激振动问题提供了理论参考;针对构建的整个动态模型,进行了相应的数字仿真分析,仿真结果验证了所得出结论的正确性。

关键词：磁浮列车自激振动机理分析仿真验证

An efficient PCR-based pool screening method for construction of BAC contigs

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An efficient PCR-based pool screening method for constructio...

第十一届全国植物基因组学大会

作者： danfeng Lv,Yan zhou,Bin Han~* National Center for Gene Research,Chinese Academy of Sciences,Shanghai,200233

As the completion of rice genome sequencing and the accumulation of the rice genomic information, we have developed an efficient rice bacterial artificial chromosome(BAC) library screening strategy for construction of...

关键词：

Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing Qiu Mengting Yang danfeng Gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug Target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels