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Nonergodic Brownian Motion in a Collinear Particle-Coupled Harmonic Chain Model

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Chinese Physics Letters 2013年第1期30卷 33-36页

作者： lu hong BAO Jing-Dong School of Physics and Chemistry Xihua UniversityChengdu 610039 Department of Physics Beijing Normal UniversityBeijing 100875

We investigate the nonergodic Brownian dynamics in a collinear particle-coupled harmonic chain model,in which the chain is free at one end and fixed at the other *** behaviors of the particle are mainly studied:the velocity thermalizes faster than the coordinate,and the asymptotic result depends on its initial coordinate preparation which is indeed a kind of the nonergodic behavior.

关键词： behavior. Brownian coordinate

Combined effects of elevated temperature and CO_2 concentration on Cd and Zn accumulation dynamics in Triticum aestivum L.

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Journal of Environmental Sciences 2016年第9期28卷 109-119页

作者： Xiaoheng Wang Yu Li hong lu Shigong Wang College of Earth and Environmental Sciences Lanzhou University School of Chemical Engineering Northwest University for Nationalities Department of Gastroenterology First Hospital of Lanzhou University School of Atmospheric Sciences Chengdu University of Information Technology College of Atmospheric Sciences Lanzhou University

A simulated climate warming experiment was conducted to evaluate the combined effects of elevated temperature and CO_2 concentration on the bioaccumulation,translocation and subcellular distributions of Cd and Zn in wheat seedlings（Triticum aestivum *** 1.） at Dingxi,Gansu Province,*** objective was to find evidence that global climate change is affecting the bioaccumulation of Cd and Zn in *** *** *** results showed that compared to control A,elevated temperature and CO_2 increased Cd bioaccumulation in the shoots by 1.4–2.5 times,and increased that in the roots by 1.2–1.5times,but decreased Zn levels in wheat shoots by 1.4–2.0 times,while decreased that in the roots by 1.6–1.9 ***,temperature and CO_2 concentration increase also led to increased Cd concentration,and decreased Zn concentration in subcellular compartments of wheat *** largest Cd concentration increase（174.4%） was observed in the cell wall and debris fractions of shoots after they were subjected to the highest CO_2 and temperature treatment（TC3）.The largest Zn concentration decrease（53.1%） was observed in the soluble（F3） fractions of shoots after they were subjected to the medium CO_2 and temperature treatment（TC2）.The temperature and CO_2 increase had no significant effect on the proportional distribution of Cd and Zn in the subcellular *** root-to-shoot translocation of Cd increased with the increasing temperature and CO_2 ***,the Zn distributions only fluctuated within a small range.

关键词： Climate warming Elevated CO_2 Elevated temperature Trace elements Wheat

Effect of Si content on impact-abrasive wear resistance of Al2O3p/steel composites prepared by squeeze casting

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Journal of Iron and Steel Research International 2018年第9期25卷 984-994页

作者： De-hong lu Hai-zhou Li Bo Ren Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093 Yunnan China

The 40Cr steel matrix composites were reinforced with Al203 particulates （Al2O3p） through Si adding to improve the impact-abrasive wear resistance, in which Si powder ranging up to 25% of the AlzO3p weight was added into the Al2O3p preforms; then, the composites were fabricated by squeeze casting. For all composites, alumina particles are evenly distributed, and Si powder is dissolved in the matrix. Without Si powder addition, the 40Cr steel matrix contains only pearlite; however, ferrite appears and increases with Si powder addition. In the impact-abrasive wear tests, the impact frequency is 80 min^-1 and the impacting energy is 2 J. With increasing Si powder, the wear of the composites first decreases obviously, reaches the minimum at 10% and then increases. The effect of Si addition on the wear resistance can be attributed to two reasons： one is increasing the hardness of the matrix, and the other is improving the interfacial bonding between Al2O3p and steel. The wear mechanism of the composites is abrasive wear when the Si powder is 〈 10 wt%. Otherwise, it is a mixed mode of abrasive and delamination wear.

关键词： Steel matrix composite Si Impact-abrasive wear Wear mechanism Al2O3 particulate Squeeze casting

COLLISION AVOIDANCE DECISION-MAKING MODEL OF MULTI-AGENTS IN VIRTUAL DRIVING ENVIRONMENT WITH ANALYTIC HIERARCHY PROCESS

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Chinese Journal of Mechanical Engineering 2008年第1期21卷 47-52页

作者： lu hong YI Guodong TAN Jianrong LIU Zhenyu State Key Laboratory of CAD＆CG Zhejiang University Hangzhou 310027 China 3D Technology Co. Ltd Ningbo 315040 China

Collision avoidance decision-making models of multiple agents in virtual driving environment are studied. Based on the behavioral characteristics and hierarchical structure of the collision avoidance decision-making in real life driving, delphi approach and mathematical statistics method are introduced to construct pair-wise comparison judgment matrix of collision avoidance decision choices to each collision situation. Analytic hierarchy process （AHP） is adopted to establish the agents＇ collision avoidance decision-making model. To simulate drivers＇ characteristics, driver factors are added to categorize driving modes into impatient mode, normal mode, and the cautious mode. The results show that this model can simulate human＇s thinking process, and the agents in the virtual environment can deal with collision situations and make decisions to avoid collisions without intervention. The model can also reflect diversity and uncertainly of real life driving behaviors, and solves the multi-objective, multi-choice ranking priority problem in multi-vehicle collision scenarios. This collision avoidance model of multi-agents model is feasible and effective, and can provide richer and closer-to-life virtual scene for driving simulator, reflecting real-life traffic environment more truly, this model can also promote the practicality of driving simulator.

关键词： Analytic hierarchy process (AHP) Collision avoidance Decision-making model Driving simulator Virtual driving environment Agent Driving behavior

Hydrophobic Poplar Prepared via High Voltage Electric Field(HVEF)with Copper as Electrode Plate

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Journal of Renewable Materials 2022年第11期10卷 2907-2919页

作者： Jianxin Cui Zehui Ju lu hong Biqing Shu Xiaoning lu College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China School of Forestry and Landscape Architecture Anhui Agricultural UniversityHefei230036China College of Civil Engineering Yangzhou Polytechnic InstituteYangzhou225127China

In order to improve hydrophobic characteristics which will affect the service performance of fast-growing poplar due to growing bacteria in the humid *** this study,a simple method was proposed to treat poplar via the high voltage electric field(HVEF)with copper as the electrode *** electron microscope(SEM),Fourier transforms infrared spectroscopy(FTIR),X-ray diffraction(XRD)and contact angle tester were adopted to evaluate the surface morphology,surface group of poplar,crystallinity and wettability under *** was found by SEM that a large number of copper particles were uniformly attached to the surface of *** all three sections,the weight percentage of the Cu element was accounting for more than *** diffraction peaks of copper-containing compounds appeared in the(XRD).FTIR analysis confirmed that the reaction between copper and poplar took *** surface contact angle of three sections of poplar increased in the following order:cross section

关键词： Poplar high voltage electric field wettability hydrophobic copper particles

Degenerate black rings in D=5 minimal supergravity

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Science China(Physics,Mechanics & Astronomy) 2021年第11期64卷 44-56页

作者： Shi-Fa Guo hong lu Yi Pang Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China

We consider both gauged and ungauged minimal supergravities in five dimensions and analyse the charged rotating solutions with two equal angular momenta *** the electric charge Q∼J^(2/3) with some specific coefficient,we find new extremal black objects emerge that are asymptotic to either Minkowski or global AdS spacetimes and can be best described as degenerate black *** near-horizon geometry is locally AdS3×S^(2),where the periodic U(1)fibre coordinate in S 3 untwists and collapses to be the degenerate part of the AdS3 *** turns out that there are two branches of extremal rotating black holes,starting as the extremal RN black holes of the same mass,but opposite *** the increasing of the angular momentum,they will join to become the same degenerate black ring,where the Gibbs free energies however are not continuous at the *** the same Q(J)relation,we find that there is in addition a rotating soliton whose mass is smaller than that of the degenerate black ring.

关键词： supergravity higher-dimensional gravity black holes black rings thermodynamics

特丁基对苯二酚的密度泛函理论计算及红外光谱分析

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原子与分子物理学报 2025年第2期42卷 33-40页

作者：张竺立逯美红高鹏慧王志军长治学院物理系山西046011

特丁基对苯二酚(Tert-butylhydroquinone,TBHQ)是一种常见的新型合成抗氧化剂,可以被用来延长食物的保质期,但过量使用会危害健康.目前的检测方法中振动光谱技术具有无损快速的优点,因此采用密度泛内涵理论与振动光谱技术相结合的研究... 详细信息

特丁基对苯二酚(Tert-butylhydroquinone,TBHQ)是一种常见的新型合成抗氧化剂,可以被用来延长食物的保质期,但过量使用会危害健康.目前的检测方法中振动光谱技术具有无损快速的优点,因此采用密度泛内涵理论与振动光谱技术相结合的研究方法可以为TBHQ的检测提供理论依据和参考.理论上,基于密度泛函理论DFT(RB3LYP)的三参数混合方法以及6-31G(d,p)和6-311++G(d,p)基组对TBHQ分子空间结构进行优化,给出了TBHQ的键长、键角和二面角等空间结构参数值,确定该分子空间构型为非平面结构.采Multiwfn和VMD程序计算并分析TBHQ分子的前线轨道和静电势,预测了该分子的反应活性位点,得出苯环和酚羟基的反应活性最强.TBHQ分子静电势最小值位于酚羟基的O原子附近,最大值位于酚羟基的H原子附近.亲电试剂和亲核试剂通过静电作用将与酚羟基发生作用.实验上,利用傅里叶变换红外光谱仪对TBHQ分子进行检测,然后在优化结构的基础上计算TBHQ分子的理论红外光谱.将得到的理论红外光谱与实验采集的数据进行对比,呈现出较好的一致性.理论计算结果可见TBHQ分子在0-2000 cm^(-1)和2000-4000 cm^(-1)范围两个区域有明显的红外活性,前者主要是指纹区的振动,后者是官能团的振动;从计算结果还可以明显看出943.9 cm^(-1)为叔丁基C-C伸缩振动以及C-H面外弯曲振动.由于-OH极性基团的取代,在1278.3 cm^(-1)、1307.1 cm^(-1)、1439.1 cm^(-1)、1587.5 cm^(-1)处出现了较强的骨架振动吸收峰和酚羟基-OH面内弯曲振动模式.这些均可作为TBHQ分子的特征峰.这为理解TBHQ的作用机理提供了重要信息,也为食品添加剂的检测研究提供了理论依据.

关键词：特丁基对苯二酚红外光谱密度泛函理论静电势前线分子轨道

Environmental effect of vegetation restoration on degraded ecosystem in low subtropical China

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Journal of Environmental Sciences 2003年第4期15卷 514-519页

作者： PENG Shao-lin YANG Liu-chun lu hong-fang South China Institute of Botany Chinese Academy of SciencesGuangzhou 510650China.

The environmental effect of degraded ecosystem's vegetation restoration in low subtropical China was studied. Results indicated that the vegetation recovery on degraded lands significantly ameliorates surrounding environment, increases species diversity, improves soil structure, raises soil fertility, enhances productivity, and promotes regional agricultural production and social economic development dramatically. Through the combining engineering and biological measures, the restoration of degraded ecosystem in low subtropical area is possible and economical. The restoration experience in Xiaoliang, Wuhua and other sites are valuable for other degraded subtropical area was introduced.

关键词： vegetation restoration degraded ecosystem low subtropical zone environment impact

Abiotic Hydrocarbons Generation Simulated by Fischer-Tropsch Synthesis under Hydrothermal Conditions in Ultradeep Basins

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1331-1341页

作者： ZHAO Zhongfeng LIU Xinran lu hong Peng Ping’an State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

FTT experiments with water as a hydrogen source and three types of possible carbon sources in the subsurface(diiron nonacarbonyl,siderite and formic acid,representing CO,CO_(2)and a simple organic acid,respectively)were carried out in this *** experimental results showed that n-alkanes with the highest carbon number of C_(33)were produced when CO was used as a carbon source(series A);a variety of polycyclic aromatic hydrocarbons(PAHs)were detected in series B with CO_(2)as a carbon source;gaseous hydrocarbons were also detected with formic acid added(series C).The different products in the three series showed that there were different hydrocarbon generation mechanisms and reaction processes with different carbon *** generation of long-chain n-alkanes in series A provided experimental support for the formation of abiogenic petroleum underground,which was of significance to early membranes on the *** in series B provide experimental support for the possibility of an abiotic source of reduced carbon on other *** carbon isotopes of gaseous hydrocarbons produced by CO exhibited a partial reversed order(δ^(13)C_(1)δ^(13)C_(3)>δ^(13)C_(4)>δ^(13)C_(5)),while the gaseous hydrocarbons produced by CO_(2)and HCOOH showed a positive order(δ^(13)C_(1)<δ^(13)C_(2)<δ^(13)C_(3)<δ^(13)C_(4)<δ^(13)C_(5)).Based on these,the alkylene mechanism and the carbonyl insertion mechanism were used to reasonably explain these characteristics.

关键词： ultra-deep basin FTT carbon isotope reversed order abiogenic hydrocarbons hydrothermal experiments