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牡丹花中不同形态酚类化合物及其抗氧化和α-葡萄糖苷酶抑制活性

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食品科学 2025年第1期46卷 83-89页

作者：陈玲王学方李智宁张立攀李晓宁二娟河南省纳普生物技术有限公司河南郑州450008 河南省科学院河南郑州450046 河南省商业科学研究所有限责任公司河南郑州450000

对丹凤和香玉两种牡丹花中的游离酚、酯键合态酚、糖苷键合态酚和不溶性结合态酚进行提取,测定不同形态酚类化合物中总酚、总黄酮含量及其主要化合物组成和含量,并对其抗氧化活性和α-葡萄糖苷酶抑制活性进行研究。结果表明,丹凤和香玉... 详细信息

对丹凤和香玉两种牡丹花中的游离酚、酯键合态酚、糖苷键合态酚和不溶性结合态酚进行提取,测定不同形态酚类化合物中总酚、总黄酮含量及其主要化合物组成和含量,并对其抗氧化活性和α-葡萄糖苷酶抑制活性进行研究。结果表明,丹凤和香玉牡丹花的游离酚的总酚和总黄酮含量最高,总酚含量分别为31.45、32.64 mg/g,总黄酮含量分别为41.11、40.67 mg/g,其次是酯键合态酚和糖苷键合态酚,不溶性结合态酚含量较低;两种牡丹花游离酚均含有17种成分,其主要成分是白藜芦醇、1,2,3,4,6-O-五没食子酰葡萄糖和大波斯菊苷;酯键合态酚、糖苷键合态酚中主要成分是山柰酚-7-O-β-D-葡萄糖苷和大波斯菊苷。不同形态酚类化合物中游离酚的抗氧化活性最强,丹凤、香玉牡丹花游离酚对1,1-二苯基-2-三硝基苯肼自由基、2,2′-联氮-二(3-乙基苯并噻唑-6-磺酸)阳离子自由基清除能力和铁离子还原能力分别为855.03、367.10、230.54μmol/g和499.06、290.64、196.39μmol/g;丹凤和香玉牡丹花的游离酚对α-葡萄糖苷酶抑制活性最强,半抑制浓度分别为12.15、13.87μg/mL。研究结果对丹凤和香玉多酚利用具有一定的参考价值。

关键词：牡丹花游离酚酯键合态酚糖苷键合态酚不溶性结合态酚抗氧化活性 α-葡萄糖苷酶抑制活性

Robust H_(∞)path tracking control of autonomous vehicles with delay and actuator saturation

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Journal of Control and Decision 2022年第1期9卷 45-57页

作者： Changfang Chen Minglei Shu Yuanyuan Yang Tianlei Gao lipan Bian Shandong Artificial Intelligence Institute Qilu University of Technology(Shandong Academy of Sciences)JinanPeople’s Republic of China Shandong Computer Science Center(National Supercomputer Center in Jinan) Qilu University of Technology(Shandong Academy of Sciences)JinanPeople’s Republic of China

The path tracking control problem is investigated in this paper for autonomous vehicles(AVs)with time-varying input delay and actuator *** on the Lyapunov-Krasovskii function and the characteristic of the saturation nonlinearity,a robust H_(∞)state-feedback path tracking controller is presented,and the corresponding control gain can be obtained by solving the linear matrix inequalities(LMIs).The asymptotic stability and prescribed H_(∞)performance conditions are studied for the closed-loop control *** reduce the cost of control system,a static robust H_(∞)output-feedback controller is also *** addition,the uncertainty effects of the cornering stiffness and external disturbances are included to improve the robustness of the control *** results are given to verify the effectiveness of the proposed theoretical results.

关键词： Path tracking robust H_(∞)control time delay actuator saturation uncertainties

Effects of biochar on water movement characteristics in sandy soil under drip irrigation

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Journal of Arid Land 2019年第5期11卷 740-753页

作者： PU Shenghai LI Guangyong TANG Guangmu ZHANG Yunshu XU Wanli lipan FENG Guangping DING Feng College of Water Resources and Civil Engineering China Agriculture UniversityBeijing 100083China Institute of Soil Fertilizer and Agricultural Water Saving Xinjiang Academy of Agricultural SciencesUrumqi 830091China Key Laboratory of Northwest Oasis Agricultural Environment Ministry of Agriculture of ChinaUrumqi 830091China

Biochar addition can improve the physical and hydraulic characteristics of sandy *** study investigated the effects of biochar on water holding capacity and water movement in sandy soil under drip *** indoor simulation experiments,the effects of biochar application at five levels(0%,1%,2%,4%and 6%)on the soil water retention curve,infiltration characteristics of drip irrigation and water distribution were tested and *** results showed that biochar addition rate was positively correlated with water holding capacity of sandy soil and soil available *** the same infiltration time,with an increasing amount of added biochar,the diffusion distance of the horizontal wetting front(HWF)tended to decrease,while the infiltration distance of vertical wetting front(VWF)initially declined and then *** features of wetted bodies changed from"broad-shallow"to"narrow-deep"*** relationship between the transport distances of HWF and VWF and the infiltration time was described by a power *** the same distance from the point source,the larger the amount of added biochar,the higher the soil water *** had a great influence on the water content of the layer with biochar(0–200 mm)and had some effects at 200–250 mm without biochar;but it had less influence on the soil water content deeper than 250 *** the application rate of biochar of 4%,most water was retained within 0–250 mm soil ***,when biochar application amount was high(6%),it would be helpful for water *** the improvement of sandy soil,biochar application rate of 4%in the plow layer had the best effect.

关键词： biochar sandy soil water holding capacity water movement drip irrigation

Effect of Relative Humidity on Resuspended Particles Caused by Human Walking

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Journal of Shanghai Jiaotong university(Science) 2020年第3期25卷 365-371页

作者： ZHENG Shuihua DU Weiyuan ZHAO lipan LI Xiangpeng College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China

The goal of this study is to investigate the effects of relative humidity on particle *** experimental study on the resuspension of different size particles is performed in the laboratory at 50%,60%,70% and 80% relative humidity *** material of flooring is shaggy *** experiments are carried out in a closed room with four laser dust instruments and a laser dust particle *** results show that when the relative humidity is 60% and 70%,the resuspension of indoor particulate matter is likely to *** walking has a greater impact on larger-size *** the conditions of different humidity,four situations all follow a rule that the larger the particle size is,the more stable the particle state is.

关键词： particulate matter resuspension relative humidity suspension rate human walking

Analysis on diffusion-induced stress for multi-layer spherical core-shell electrodes in Li-ion batteries

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Chinese Physics B 2021年第9期30卷 587-593页

作者： Siyuan Yang Chuanwei Li Zhifeng Qi lipan Xin Linan Li Shibin Wang Zhiyong Wang Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300350China Tianjin Key Laboratory of Modern Engineering Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300350China

Silicon-based carbon composites are believed as promising anodes in the near future due to their outstanding specific capacity and relatively lower volume effect compared to pure silicon ***,a multilayer spherical core-shell(M-SCS)electrode with a graphite framework prepared with Si@O-MCMB/C nanoparticles is developed,which aims to realize chemically/mechanically stability during the lithiation/delithiation process with high specific *** electrochemical-/mechanical-coupling model for the M-SCS structure is established with various chemical/mechanical boundary *** simulation of finite difference method(FDM)has been conducted based on the proposed coupling model,by which the diffusion-induced stress along both the radial and the circumferential directions is ***,factors that influence the diffusion-induced stress of the M-SCS structure have been discussed and analyzed in detail.

关键词： multi-layer spherical core-shell electrode diffusion-induced stress

Monte Carlo simulation for pulsed neutron-neutron logging in fractured and cavernous carbonate formation

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Global Geology 2020年第1期23卷 32-37页

作者： LIU lipan MO Xiuwen ZHANG Youshuo ZHANG Weifeng College of Geo-Exploration Science and Technology Jilin UniversityChangchun 130026China Sinopec Northeast Oilfield Branch Company Changchun 130060China Research Institute of Sinopec Northwest Oilfield branch Urumchi 830000China

The influence of carbonate formation on Pulsed Neutron logging(such as Pulsed Neutron-Neutron logging)is quite different from that of sandstone due to the complexity of reservoir architecture and the development of fracture in carbonate *** study the factors affecting Pulsed Neutron-Neutron(PNN)logging in carbonate formation,the responses on fracture or cave are simulated by Monte Carlo method,getting the relationships among the macroscopic capture cross section(Σ),the count ratio of the thermal neutron at far spacing and near spacing detectors(RATIO),the fracture porosity,oil-bearing and shale content of *** results show that PNN logging can be used to detect caves,and there exist linear relationships among the macroscopic capture cross section(Σ),the count ratio(RATIO)and the above *** research findings in this paper provides theoretical basis for the interpretation and data correction of the PNN logging in carbonate reservoirs.

关键词： carbonate formation PNN logging macroscopic capture cross section RATIO Monte Carlo simulation

A Relation-Based Modeling Method for Workshop Reconfiguration

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International Journal of Plant Engineering and Management 2004年第4期9卷 205-214页

作者： lipan-ring QINXian-sheng WANGKe-qin LIMin NorthwesternPolyteehniealUniversity Xi＇an710072P.R.China NorthwesternPolyteehniealUniversity Xi＇an710072P.R.China

To respond to the changes in the m arket rapidly, the workshop has become an ever-changing dynamic environment in regard to personnel change and organization alternation, etc. Therefore it is ne cessary to reconfigure the workshop system. In this paper, we present the point of view that the closer the relations are among elements in the system, the clos er they should be connected with each other when they are integrated in designin g and structural modeling of the workshop system. At first, this paper discusses the relationship among elements in the workshop system and events describing th e relationship, and provides a technical overview of the expression, definition and classification of relationship. This paper focuses on the steps and algorith m to evaluate the degree of closeness of relations among elements in systems, an d emphasizes the modeling methods for workshop reconfiguration by use of a fuzzy cluster. In light of the above steps and methods, types and contents of basic r elationships among elements should be determined, and a standard relation tree s hould be set up. Then, correlation coefficients are calculated by the standard r elation tree, and a fuzzy relation matrix is built up. After that, the structure modeling of the workshop equipment system can be completed through a fuzzy clus ter. The paper ends with an application of a FMS(Flexible Manufactuing System) f unction system modeling. Results of the modeling and calculations are presented.

关键词： relation equipment reconfiguration modeling

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旅游宰客现象治理中的政府责任与机制

云南行政学院学报 2018年第3期20卷 61-69页

作者：李盼凯里学院旅游学院贵州凯里556000

近年来,中国旅游业的发展突飞猛进,然而,欺客、宰客等旅游乱象的层出不穷阻碍了旅游业的健康、持续发展。本文通过文献阅读和实地调研收集数据,采用定性分析的方法揭示了旅游宰客现象产生的机理,并探索在旅游宰客现象治理中的政府责任... 详细信息

近年来,中国旅游业的发展突飞猛进,然而,欺客、宰客等旅游乱象的层出不穷阻碍了旅游业的健康、持续发展。本文通过文献阅读和实地调研收集数据,采用定性分析的方法揭示了旅游宰客现象产生的机理,并探索在旅游宰客现象治理中的政府责任与机制。认为政府是旅游宰客现象治理的核心力量,并应该从以下几个方面建立合理的治理机制:建立合理的利益分配机制;建立旅游公共信息服务平台;建立健全监管机制,维护市场秩序;建立政府各职能部门的协作机制;提高立法质量,完善法制环境;建立旅游从业人员的管理与培训机制。政府可通过治理机制把旅游宰客现象治理中的政府责任内化为政府及其公务人员的本质工作,并积极主动地按照责任要求去完成,以达到有效治理旅游宰客现象的目的,确保旅游目的地的经济、社会、旅游健康、有序发展。

关键词：旅游宰客治理政府责任机制

基于改进PNCC的车载噪声环境下说话人识别研究

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基于改进PNCC的车载噪声环境下说话人识别研究

作者：李潘成都理工大学

学位级别：硕士

说话人识别是根据不同说话人语音信号中的独特信息来判定该语音发出者的身份,也称为声纹识别。它是基于行为特征和生理特征的一种生物识别技术,相较于人脸识别和指纹识别,具有采集成本低,用户易接受,可远程认证等优点,被广泛应用于刑侦... 详细信息

说话人识别是根据不同说话人语音信号中的独特信息来判定该语音发出者的身份,也称为声纹识别。它是基于行为特征和生理特征的一种生物识别技术,相较于人脸识别和指纹识别,具有采集成本低,用户易接受,可远程认证等优点,被广泛应用于刑侦、安防、金融等领域。近年来,说话人识别技术研究取得了重大进步,在安静环境下能达到99%以上的识别准确率,但在噪声复杂的车载环境,存在训练模型的环境与使用环境不匹配,导致系统识别准确率急剧下降,以至于无法识别的问题,为有效解决上述问题,论文做了以下改进:在语音数据预处理阶段,提出小波阈值去噪与VMD（Variational Mode Decomposition,变分模态分解）算法结合的语音增强算法,用于前端噪声去除,主要是将混噪语音信号用VMD分解为多个IMF（Intrinsic Mode Function,本征模态函数）分量,比较每个IMF与原信号的相关系数值,并将其门限值设为0.3,对恰好低于门限值的一个噪声成分IMF使用小波阈值去噪,并与高于门限值的分量重构出原信号达到去噪的效果。纯净语音信号中加入white噪声、vovlo噪声及carhorn噪声数据集,并以-5,0,5,10,15db信噪比混合,去噪效果以分段信噪比和语音质量感知评估衡量。所提出的改进方法相对于VMD算法在volvo噪声小信噪比时有较大提升,信噪比为-5,0,5时,其相对提升分别为10.14%,6.15%,1.77%,在carhorn噪声中,语音质量相对改善5%左右。在说话人识别特征提取阶段,采用对噪声鲁棒性更好的PNCC（Power-Normalized Cepstral Coefficients,幂率归一化倒谱系数）特征参数作为说话人的声学特征,改用长时功率估计和通道偏差最小化对环境噪声进行抑制,结合残差卷积网络ResCNN,并使用Softmax和三元组进行模型训练。改进的说话人识别系统在PC端使用TensorFlow框架实现,在车载多种噪声环境下,与采用其他特征参数构建的系统进行比较,论文构建的说话人识别系统的等错误率更低,识别准确率在低信噪比下提升较大。最后,在PyCharm中利用pyqt5库做了人机交互的界面,便于录入语音进行注册和验证。

关键词：说话人识别 PNCC VMD 小波阈值去噪