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Can Flory-Stockmayer theory be applied to predict conventional free radical polymerization of multivinyl monomers？ A study via Monte Carlo simulations

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Science China Chemistry 2018年第3期61卷 319-327页

作者： Jing Lyu yongsheng gao Zidan Zhang Udo Greiser Hongyun Tai Wenxin Wang School of Materials Science and Engineering Tianjin University Tianjin 300350 China Charles Institute of Dermatology School of Medicine University College Dublin Dublin 4 Ireland Division of Polymer Chemistry and Materials Department of Chemistry Katholieke Universiteit Leuven Celestijnenlaan 200E B-3001 Heverlee Belgium School of Chemistry Bangor University Deiniol Road Bangor Gwynedd LL57 2UW UK

The conventional free radical polymerization(FRP) of multivinyl monomers(MVMs) inevitably leads to gelation even at low monomer conversion resulting in difficulties to control and monitor the reaction process. Flory and Stockmayer(F-S theory)studied it based on two fundamental assumptions:(1) independent and equivalent vinyl groups;(2) no intramolecular ***, until now its applicability to FRP of MVMs(especially regarding the extent of intramolecular cyclization) is still controversial. In this paper, Monte Carlo simulations are used to study FRP of divinyl monomers by two kinetic models:with/without cyclization models. The results of the simulations are compared with the calculated gel points based on F-S theory and the experimental data. It is found that the intramolecular cyclization has a negligible impact on the polymerization process and the gel point before gelation, which are in agreement with the prediction by F-S theory, but the effect becomes significant above the gel points.

关键词： Monte Carlo F-S theory FRP multivinyl monomers intramolecular cyclization

Effects of lanthanum on the growth and essential oil components of lavender under osmotic stress

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Journal of Rare Earths 2018年第8期36卷 891-897页

作者： Liyun Zhu Linzhen Song yongsheng gao Junqing Qian Xiaodong Zhang Sufang Li College of Modem Science and Technology China Jiliang University Hangzhou 310018 China Anhui Hanfang Bio-tech Co. Ltd. Huaibei 235000 China National & Local United Engineering Lab of Quality Controlling Technology and Instrumentation for Marine Food China Jiliang University Hangzhou 310018 China College of Biotechnology and Bioengineering Zhejiang University of Technology Hangzhou 310012 China

The effects of lanthanum on growth, soluble sugar content, essential oil contents and quality were studied in lavender plant（Lavandula Angustifolia Mill, Variety 701） under osmotic stress by means of PEG-6000 solution. The results show that osmotic stress could reduce the growth rate of lavender, and increase the content of SSC（soluble sugar concentration） to some extent. Compared with control group,the contents of essential oil in flowers and leaves respectively increase by 45.6% and 48.3% in the osmotic stress group induced by 15% PEG-6000. However, the presence of lanthanum can make the contents of essential oil in the flowers and leaves of stressed lavender plants enhance by 19.4% and 18.6%, respectively. Under osmotic stress, the relative contents of four kinds of lavender essential oil compositions of camphor, linalool, linalyl acetate and lavandulol acetate in the lavender flowers were successively 22.63%,0.61%,25.46%,7.03%,and 20.17%,0.62%,20.72%,10.80%,respectively in the presence and absence of lanthanum. The contents of all four main components of lavender essential oils meet the requirements of the national standard under osmotic stress in the presence of lanthanum. However, in the absence of lanthanum, the contents of linalyl acetate and lavandulol acetate does not meet the requirements of the national standard under osmotic stress. Moreover, the contents of five components of borneol, camphor,eudesmol, caryophyllene oxide and bicyclic sesquiphellandrene from the essential oil of lavender leaves are 12.89%, 3.84%, 8.76%, 11.30% and 8.10%, respectively. The total content of above five components accounts for 44.89% of the essential oil of the lavender leaves. Particularly, the borneol content in leaf essential oil is up to 12.89%. It is 125.2 times the amount of borneol in the flower essential oil. In conclusion, the suitable concentration of lanthanum can improve the adaptability of lavender plants, and heighten the content and quality of lavender essen

关键词： Lanthanum Lavender Essential oil Secondary metabolites Osmotic stress Rare earths

Mobile robot path planning method combined improved artificial potential field with optimization algorithm

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High Technology Letters 2011年第2期17卷 160-165页

作者：赵杰 Yu Zhenzhong Yan Jihong gao yongsheng Chen Zhifeng State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150080 P. R. China

To overcome the shortcomings of the traditional artificial potential field method in mobile robot path planning, an improved artificial potential field model （IAPFM） was established, then a new path planning method combining the IAPFM with optimization algorithm （trust region algorithm） is proposed. Attractive force between the robot and the target location, and repulsive force between the robot and the obstacles are both converted to the potential field intensity; and filled potential field is used to guide the robot to go out of the local minimum points ; on this basis, the effect of dynamic obstacles velocity and the robot＇s velocity is consid thers and the IAPFM is established, then both the expressions of the attractive potential field and the repulsive potential field are obtained. The trust region algorithm is used to search the minimum value of the sum of all the potential field inten- sities within the movement scope which the robot can arrive in a sampling period. Connecting of all the points which hare the minimum intensity in every sampling period constitutes the global optimization path. Experiment result shows that the method can meet the real-time requirement, and is able to execute the mobile robot path planning task effectively in the dynamic environment.

关键词： trust region optimization algorithm path planning artificial potential field mobile robot potential field intensity

Improved Flight Conflict Detection Algorithm Based on Gauss-Hermite Particle Filter

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Wuhan University Journal of Natural Sciences 2017年第3期22卷 269-276页

作者： MA Lan gao yongsheng YIN Tianyi ZHAI Wenpeng College of Air Traffic Management Civil Aviation University of China

In order to improve the accuracy of free flight conflict detection and reduce the false alarm rate, an improved flight conflict detection algorithm is proposed based on Gauss-Hermite particle filter（GHPF）. The algorithm improves the traditional flight conflict detection method in two aspects：（i） New observation data are integrated into system state transition probability, and Gauss-Hermite Filter（GHF） is used for generating the importance density function.（ii） GHPF is used for flight trajectory prediction and flight conflict probability calculation. The experimental results show that the accuracy of conflict detection and tracing with GHPF is better than that with standard particle filter. The detected conflict probability is more precise with GHPF, and GHPF is suitable for early free flight conflict detection.

关键词： free flight conflict detection Gauss-Hermite particle filter importance probability density function observation data

An efficient self-reconfiguration method to deploy space modular robots

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Science China Technological Sciences 2024年第12期67卷 3962-3964页

作者： ZHAO Ning gao yongsheng QI Jian YANG ZhiYuan ZHAO SiKai SUI Xin HAN Kai ZHAO Jie ZHU YanHe State Key Laboratory of Robotics and System Harbin Institute of Technology

Intelligent robots play a crucial role in space exploration, representing a significant trend in space automation technology. Modular robots, which can regenerate configurations and functions through self-reconfiguration [1],offer distinct adaptability and versatility [2,3] over traditional robots with fixed structures and single-purpose functions. Therefore, self-reconfiguration is regarded as a highly promising capability for space exploration and remains a primary motivation for research in this field [4].

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High-Field-Strength Elements in Mafic Volcanics from North China Craton: Implications for Archean-Proterozoic Boundary and Source Composition

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Journal of Earth Science 1998年第2期17卷 17-23页

作者： Liu yongsheng gao Shan Luo Tingchuan Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074

Archean to Cenozoic mafic volcanic rocks from the North China craton are studied. They show Archean Proterozoic (Ar Pt) boundary and geochemical anomalies in Cenozoic basalts. Proterozoic mafic volcanics are enriched in most of the high field strength elements (HFSE) compared with Archean ones. Nb, Ta and Th show a distinct sequence of incompatibility in Archean and Proterozoic. The Cenozoic basalts are enriched in HFSE and Ni and their REEs are strongly differentiated with positive Eu anomalies ( δ (Eu)=1.14). The Ar Pt boundary could be related to change in oxygen fugacity and requires an increasing importance of enriched mantle source. The geochemistry of Cenozoic basalts implies a mantle source similar to OIB. Residuum from subducting partial melting of old basaltic oceanic crust and continental crust is likely to contribute to the formation of the enriched mantle.

关键词： mafic volcanic rocks high field strength element Archean Proterozoic boundary enriched mantle.

Application Status of Life Cycle Assessment in Chinese Automotive Industries

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Application Status of Life Cycle Assessment in Chinese Autom...

基于相干双光频梳的微波光子信道化接收技术研究

2016中国汽车工程学会年会暨展览会

作者： Yu Haiyan Zhou Chenxiao gao yongsheng School of Automotive Studies Tongji University Research Institute of Baoshan Iron Steel Co. Ltd

Application status of life cycle assessment（LCA） method in Chinese automotive industries is reviewed.A questionnaire that includessome key issues on LCA application in China was sent to some OEMs,suppliers and *** feedback data was analyzed and discussed in *** results showed that about 60 percent Chinese automotive industries have used the LCA tools in some or all of their products manufacturing *** first three reasons that hinder the application of LCA in Chinese automotive industries are technique problems,lack of government support and worrying about the cost that may be enhanced due to the LCA ***,Gabi and internal database share about 90 percent of LCA database requirement.A precise,low- price and easy use database that considers Chinese true resources and industrial technology is in urgent need for popularizing LCA in China.

关键词： life cycle assessment Chinese automotive industry database questionnaire

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cnki会议

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通信学报 2020年第12期41卷 94-99页

作者：陈博樊养余高永胜西北工业大学电子信息学院陕西西安710048 咸阳师范学院物理与电子工程学院陕西咸阳712000

为了满足宽带通信的发展需求,提出了一种基于相干双光频梳的微波光子信道化接收机,所用的光频梳仅需一个双平行马赫−曾德尔调制器就可生成,平坦度高,外带抑制比高,自由谱范围灵活可调,并且有效简化了接收机的复杂程度。在I/Q解调模块中... 详细信息

为了满足宽带通信的发展需求,提出了一种基于相干双光频梳的微波光子信道化接收机,所用的光频梳仅需一个双平行马赫−曾德尔调制器就可生成,平坦度高,外带抑制比高,自由谱范围灵活可调,并且有效简化了接收机的复杂程度。在I/Q解调模块中,利用平衡探测方法不仅有效抑制了二阶交调失真和直流偏移,还提高了接收机的动态范围,同时利用电耦合器配合电带通滤波器解决了超外差架构普遍存在的镜像干扰问题,最终实现了5 GHz带宽射频信号的信道化接收。

关键词：微波光子信道化光频梳镜像抑制 I/Q平衡探测

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拜耳法原料磨提产途径探讨

轻金属 2001年第4期 16-19页

作者：高永胜中国长城铝业公司氧化铝厂河南郑州450041

本文介绍了中国长城铝业公司氧化铝厂拜耳法原料磨的磨矿现状及存在问题 ,并对影响拜耳法原料磨提产的限制因素进行了系统的分析阐述 ,提出了相应的解决途径和改进措施。

关键词：拜耳法原料磨产量氧化铝磨矿技术改造