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I_2(X^1∑_g^+)分子在脉冲射流中的振动弛豫

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内蒙古大学学报（自然科学版） 1989年第3期20卷 331-336页

作者：燕春黄瑞平内蒙古大学物理系中国科学院大连化学物理研究所

本文利用激光诱导荧光时间分辩光谱技术,测量了I_2(X^1)分子在He及Ar载气脉冲射流中振动温度随时间的变化关系。实验结果表明,I_2分子振动态是非玻尔兹曼布居的,振动温度约经过300μS达到稳定值,通过一段平滑变化后,振动温度又开始升高... 详细信息

本文利用激光诱导荧光时间分辩光谱技术,测量了I_2(X^1)分子在He及Ar载气脉冲射流中振动温度随时间的变化关系。实验结果表明,I_2分子振动态是非玻尔兹曼布居的,振动温度约经过300μS达到稳定值,通过一段平滑变化后,振动温度又开始升高。振动温度的整个变化过程与脉冲气流的建立过程相似,可以将其分为稳态和非稳态两个过程。利用“突然冷凝”模型,得到了I_2(X^1)分子v″=1及v″=2振动态的弛豫截面。

关键词： I2分子振动弛豫脉冲射流

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眼树莲的化学成分分析

中国实验方剂学杂志 2017年第16期23卷 96-100页

作者：余邦良刘寿柏黄内利杨柳杨梦成樊好飞戴好富海南医学院药学院海口571119 中国热带农业科学院热带生物技术研究所海南省黎药资源天然产物研究与利用重点实验室海口571101

目的:对萝藦科眼树莲Dischidia chinensis全株的化学成分进行分离纯化并对分离得到的单体化合物进行结构鉴定。方法:眼树莲全株干重5.0 kg,粉碎,用95%乙醇室温浸提3次,过滤,合并滤液后经真空减压浓缩得粗浸膏,将其分散于水中成悬浊液,... 详细信息

目的:对萝藦科眼树莲Dischidia chinensis全株的化学成分进行分离纯化并对分离得到的单体化合物进行结构鉴定。方法:眼树莲全株干重5.0 kg,粉碎,用95%乙醇室温浸提3次,过滤,合并滤液后经真空减压浓缩得粗浸膏,将其分散于水中成悬浊液,依次用石油醚、乙酸乙酯和正丁醇萃取。运用小孔树脂(MCI),硅胶柱色谱,LH-20羟丙基葡聚糖凝胶(Sephadex LH-20)等柱色谱方法对眼树莲乙酸乙酯萃取物经行分离纯化,应用TLC跟踪监测,分离得到纯度较高的单体化合物。依据各个化合物的理化常数和波谱数据分析对各单体化合物的化学结构进行进一步鉴定。结果:从眼树莲中分离鉴定了10个化合物,分别为β-香树素(1),羽扇豆醇(2),β-香树素乙酸酯(3),3-表木栓醇(4),香草醛(5),4-羟基-3,5-二甲氧基苯甲醛(6),2-羟基-1-(4-羟基-3-甲氧基-苯基)-丙基-1-酮(7),1-(4-hydroxy-3-methoxyphenyl)-1-methoxypropan-2-ol(8),pavonisol(9),S(+)-dehydrovomifoliol(10)。结论:化合物1~10均为首次从眼树莲中分离得到。

关键词：眼树莲化学成分分离鉴定乙酸乙酯萃取物

Communication Scheduling with Diversity for Unmanned Aircraft Systems Using Local 5G

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Journal of Communications and Information Networks 2020年第1期5卷 50-61页

作者： Takeru Kitagawa Yuichi Kawamoto nei Kato Graduate School of Information Sciences Tohoku University Aramaki-Aoba 6-3-09Aoba-kuSendai980-8579Japan

The use of unmanned aircraft systems(UAS)for critical public service missions by public organizations,local governments,and social users is *** radio transmission by unmanned aerial vehicles(UAVs)is indispensable in these *** of the standards suitable for UAV wireless communications is local ***,to introduce local 5G into a UAS,several problems specific to UASes must be *** include the deterioration of the signal-to-noise ratio due to topography and obstacles,the uncertainty of the communication environment due to the movement of multiple UAVs,and the limitation of the frequency *** address these problems and to introduce local 5G into the UAS,we propose a novel communication scheduling *** method incorporates transmission modes with *** evaluations shows that total data volumes increase by 1.9~3 times with the proposed scheduling method compared with transmission without diversity or efficient scheduling.

关键词： unmanned aircraft system(UAS) unmanned aerial vehicle(UAV) local 5G diversity scheduling LTE sidelink time division multiple access(TDMA)

High-performance nickel metal hydride battery anode with enhanced durability and excellent low-temperature discharge capability

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Nano Research 2024年第10期17卷 8819-8825页

作者： Zhitao Chen Huitian Liu Jean nei Nian Liu School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA GP Batteries HongkongChina

Current AB_(5)-type hydrogen storage alloys employed in nickel-metal hydride(NiMH)batteries exhibit exceptional low-temperature discharge performance but suffer from limited cycle life and insufficient high-temperature *** overcome these challenges,we introduce a hydrothermal synthesized LaF_(3)coating layer on the surface of the AB_(5)anode *** LaF_(3)coating layer adds a protective barrier for the active material,significantly improving the battery's cycle life and high-temperature *** findings indicate that(1)the LaF_(3)coated anode demonstrates an extended cycle life with increased specific capacity and a capacity retention of 88%after 40 cycles of abusive overcharging and rapid discharging at room temperature.(2)The synthesized anode exhibits a 97%recovery of its specific capacity of 292.7 mAh/g following 144 h of high-temperature storage.(3)The low-temperature discharge capacity of the synthesized anode remains on par with the pristine AB_(5)alloy at 230.4 mAh/g in a-40℃*** research presents a significant advancement in hydrogen storage alloy coatings and offers valuable insights for designing electrodes in NiMH batteries.

关键词： nickel metal hydride(NiMH)batteries hydrothermal synthesis lanthanum fluoride discharge capacity low temperature

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渭河流域水利水保工程对洪水影响分析研究

西北水电 2004年第1期 1-3,17页

作者：张志红李伟佩芮孝芳黄国如黄委会勘测规划设计研究院郑州450003 河海大学南京210098

渭河流域由于其下垫面条件的复杂性和人类活动的多样性以及降水时空分布的不均匀性,给研究流域洪水形成及变化规律带来较大困难。通过大量实地调查,分析了渭河流域水利水保工程对实测洪水的影响;进而利用流域水文模型,定量分析下垫面条... 详细信息

渭河流域由于其下垫面条件的复杂性和人类活动的多样性以及降水时空分布的不均匀性,给研究流域洪水形成及变化规律带来较大困难。通过大量实地调查,分析了渭河流域水利水保工程对实测洪水的影响;进而利用流域水文模型,定量分析下垫面条件变化和暴雨时空变化对设计洪水的影响。结论认为:渭河流域设计洪水计算中,可既不考虑水库工程影响还原,也不考虑设计条件下工程的影响。

关键词：渭河流域水利水保工程洪水设计洪水流域水文模型

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GUEST EDITORIAL

China Communications 2017年第1期14卷 18-19页

作者： Supeng Leng Yan Zhang nei Kato the School of Communication and Information Engineering University of Electronic Science and Technology of ChinaChina the Department of Informatics University of OsloNorway 不详

The IEEE/CIC International Conference on Communication in China（ICCC）has been globally recognized as one of the important annual international conference held by the IEEE Communication Society（Com Soc）and China In... 详细信息

关键词： globally fifth users desired distinguished carefully authority permission Chengdu maximize

A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： Carlos Antonio Ribeiro Duarte Francisco Joséde Souza Diego nei Venturi Martin Sommerfeld Department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed *** are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged *** option,although less commonly used,is the vortex-chamber *** both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating *** present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged *** are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion *** analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe *** general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of *** the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading ***,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics

Effective and simple recovery of 1,3-propanediol from a fermented medium by liquid–liquid extraction system with ethanol and K_3PO_4

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Chinese Journal of Chemical Engineering 2018年第1期26卷 104-108页

作者： Daiana Wischral Hongxin Fu Fernando L.Pellegrini Pessoa nei Pereira Jr Shang-Tian Yang School of Chemistry Department of Biochemical EngineeringFederal University of Rio de Janeiro William G.Lowrie Department of Chemical and Biomolecular Engineering The Ohio State University School of Chemistry Department of Chemical EngineeringFederal University of Rio de Janeiro

1,3-Propanediol,traditionally obtained from fossils,has numerous industrial applications,including use in the production of high performance *** microbial production of 1,3-propanediol presents several opportunities,and the final purity grade determines its price and commercial *** development of novel separation technology could improve the economic viability of the bioproduction of 1,***,we investigated salting-out extraction as a novel process for 1,3-propanediol recovery from fermentation ***,a screening for the best salt/solvent combination was conducted and then optimized using the response surface *** solvents studied were methanol,ethanol,isopropanol and acetone,and the salts examined were K_2HPO_4,Na_2CO_3,K_2CO_3,(NH_4)_2SO_4,NaHPO_4,K_3PO_4 and C_6H_5NaO_*** optimal extraction system consisted of 34 wt%K_3PO_4,28 wt% ethanol,and 38 wt% fermentation broth containing 23.0 g·L^(-1)1,3-propanediol,which gave the highest partition coefficient of 33 and recovery yield of 97%.The results demonstrated that salting-out extraction was a promising method for 1,3-propanediol recovery from fermentation broth.

关键词： Fermentation Downstream process 1 3-Propanediol Clostridium beijerinckii Liquid-liquid extraction Salting-out extraction

Temporal-spatial cross-correlation analysis of non-stationary near-surface wind speed time series

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Journal of Central South University 2017年第3期24卷 692-698页

作者： ZENG Ming LI Jing-hai MENG Qing-hao ZHANG Xiao-nei Institute of Robotics and Autonomous Systems Tianjin Key Laboratory of Process Measurement and Control （School of Electrical Automation and Information Engineering Tianjin University） Tianjin 300072 China

Temporal-spatial cross-correlation analysis of non-stationary wind speed time series plays a crucial role in wind field reconstruction as well as in wind pattern ***,the near-surface wind speed time series recorded at different locations are studied using the detrended fluctuation analysis(DFA),and the corresponding scaling exponents are larger than *** indicates that all these wind speed time series have non-stationary ***,concerning this special feature( i.e.,non-stationarity)of wind signals,a cross-correlation analysis method,namely detrended cross-correlation analysis(DCCA) coefficient,is employed to evaluate the temporal-spatial cross-correlations between non-stationary time series of different anemometer ***,experiments on ten wind speed data synchronously collected by the ten anemometers with equidistant arrangement illustrate that the method of DCCA cross-correlation coefficient can accurately analyze full-scale temporal-spatial cross-correlation between non-stationary time series and also can easily identify the seasonal component,while three traditional cross-correlation techniques(i.e.,Pearson coefficient,cross-correlation function,and DCCA method) cannot give us these information directly.

关键词： temporal-spatial cross-correlation near-surface wind speed time series detrended cross-correlation analysis (DCCA) cross-correlation coefficient Pearson coefficient cross-correlation function