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Numerical simulation analysis of wind field above pavement surface in different landforms by computational fluid dynamics approach

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 559-573页

作者： jian Ouyang Zhao jiang Leiyu Ye Jing Li Peng Cao School of Civil Engineering and Architecture Hainan UniversityHaikou 570000China School of Transportation and Logistics Dalian University of TechnologyDalian 116024China Hexagon Manufacturing Intelligence(Qingdao)Co. Ltd.Qingdao 266000China China Tower Co. Ltd.Dalian BranchDalian 116024China Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

The temperature and moisture of the pavement structure can be greatly influenced by the wind speed above pavement *** wind speed above pavement surface not only is dominated by the wind speed of atmosphere,but also it is highly related to the landform and buildings around ***,currently there are no studies about the wind field above pavement surface in consideration of the effect of the landform and buildings.A simulation method,which is combined with geographic information system(GIS),wind data from meteorological observatory and computational fluid dynamics(CFD)software,is employed to study the effect of the landform and the wind speed of atmosphere on the wind field above pavement *** cases are studied,including an urban road,a coastal road and a mountainous ***,the wind field distribution above road surface in different wind directions was studied in our *** indicate that the wind field above pavement surface can be greatly affected by the landforms,buildings and wind *** simulation method can provide reliable results for the wind field above pavement *** maximum relative errors between simulated and measured wind speed can be less than 20%in the analysis of the three *** is recommended that the CFD simulation method is a good tool to accurately know the wind field above pavement surface.

关键词： Wind field above pavement surface Computational fluid dynamics Landforms Geographic information system Simulation

碳酸钠/甘油体系中六氯苯脱氯去除及影响因素研究

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中国环境科学 2015年第1期35卷 122-128页

作者：黄海蒋建国肖叶清华大学环境学院北京100084 北京鼎实环境工程有限公司北京100029 清华大学固体废物处理与环境安全教育部重点实验室北京100084 清华大学区域环境质量协同创新中心北京100084

以六氯苯(HCB)为对象,以HCB脱氯和去除效率为考察指标,通过研究不同的氢供体、碱性物质、催化剂和反应温度等因素,逐步建立基于碳酸钠(Na2CO3)/甘油的高效碱催化脱氯(BCD)体系.结果表明,碱性物质的投加量对HCB的脱氯效率影响显著,当HCB... 详细信息

以六氯苯(HCB)为对象,以HCB脱氯和去除效率为考察指标,通过研究不同的氢供体、碱性物质、催化剂和反应温度等因素,逐步建立基于碳酸钠(Na2CO3)/甘油的高效碱催化脱氯(BCD)体系.结果表明,碱性物质的投加量对HCB的脱氯效率影响显著,当HCB、铁粉、Na2CO3和甘油的投加质量比为1:1:12:90时,在250℃下反应2.5h后,HCB的去除率达到99.9%,脱氯效率达到91.9%,部分氯苯已完全脱氯生成苯.研究结果证明了弱碱性物质也能高效催化HCB的脱氯降解.碳酸钠/甘油体系对HCB具有高效的脱氯效率,所用原料资源丰富、廉价,具有较好的应用前景.

关键词：碱催化六氯苯碳酸钠甘油脱氯

Hybrid modeling for carbon monoxide gas-phase catalytic coupling to synthesize dimethyl oxalate process

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Chinese Journal of Chemical Engineering 2024年第6期70卷 234-250页

作者： Shida Gao Cuimei Bo Chao jiang Quanling Zhang Genke Yang jian Chu Ningbo Artificial Intelligence Institute Shanghai Jiao Tong UniversityNingbo 315012China Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Industrial Internet+Safety Production of Hazardous Chemical Ministry of Emergency ManagementNanjing Tech UniversityNanjing 211816China

Ethylene glycol(EG)plays a pivotal role as a primary raw material in the polyester industry,and the syngas-to-EG route has become a significant technical route in *** carbon monoxide(CO)gas-phase catalytic coupling to synthesize dimethyl oxalate(DMO)is a crucial process in the syngas-to-EG route,whereby the composition of the reactor outlet exerts influence on the ultimate quality of the EG product and the energy consumption during the subsequent separation ***,measuring product quality in real time or establishing accurate dynamic mechanism models is *** effectively model the DMO synthesis process,this study proposes a hybrid modeling strategy that integrates process mechanisms and data-driven *** CO gas-phase catalytic coupling mechanism model is developed based on intrinsic kinetics and material balance,while a long short-term memory(LSTM)neural network is employed to predict the macroscopic reaction rate by leveraging temporal relationships derived from archived *** proposed model is trained semi-supervised to accommodate limited-label data scenarios,leveraging historical *** integrating these predictions with the mechanism model,the hybrid modeling approach provides reliable and interpretable forecasts of mass *** investigations unequivocally validate the superiority of the proposed hybrid modeling approach over conventional data-driven models(DDMs)and other hybrid modeling techniques.

关键词： Carbon monoxide Dynamic modeling Hybrid model Reaction kinetics Semi-supervised learning

Highly crystallization-induced emissive luminophores with mechanoluminescent features for two-photon harvesting fluorescence imaging and latent fingerprint identification

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Nano Research 2024年第7期17卷 6475-6482页

作者： jian Lu Juan Gao Rui-Xuan Qian Shuai-Hua Wang Fa-Kun Zheng guo-Cong guo Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Fluorescence imaging can be employed in fields of medical treatment,astronomical exploration,and national defense *** fluorescence imaging often takes the single-photon techniques,which is vulnerable to background interference and ***,two-photon fluorescence imaging can achieve much higher-resolution fluorescence imaging for reducing scattering and deeper ***,by assembling the tetraphenylethylene backbones with nontoxic and non-noble K^(+)ions,compound 1([(Hdma)K(H_(2)ettc)]_(n),H_(4)ettc=4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid)))with the crystallization-induced emissions exhibited charming fluorescence imaging under two-photon excitation microscopy(TPEM).Besides,luminescent powders based on compound 1 can achieve high-resolution fingerprint recognition,providing secure access control and identification for a novel authentication *** with the commercial fluorescent dyes coumarin-6,the as-synthesized compound 1 showed great solvent stability,indicating its durability against harsh ***,compound 1 shows mechanoluminescent properties for the perturbation of weak supramolecular interactions within ordered arrangements of the H_(2)ettc^(2−)*** novel compound has provided an important insight to the development of twophoton fluorescence imaging and advanced external-stimuli responsive materials.

关键词： crystallization-induced emission fluorescence imaging two-photon absorption fingerprint recognition mechanoluminescence

维普期刊数据库评论

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基于对称电压矢量组的直接转矩控制

中国电机工程学报 2006年第23期26卷 139-144页

作者：朱琰佘焱姜建国上海交通大学电子信息与电气工程学院上海市徐汇区200240

提出了一种新型的直接转矩控制策略和定子磁链观测误差校验方法。通过分析SPWM的特点,设计出基于对称电压矢量组的调制方法,并探讨了采用此方法时三相桥式电压型逆变器的电压输出能力。该调制方法获得方向任意且大小可控的等效电压矢量... 详细信息

提出了一种新型的直接转矩控制策略和定子磁链观测误差校验方法。通过分析SPWM的特点,设计出基于对称电压矢量组的调制方法,并探讨了采用此方法时三相桥式电压型逆变器的电压输出能力。该调制方法获得方向任意且大小可控的等效电压矢量,以此控制定子磁链的幅值和旋转速度,从而达到对输出电磁转矩的有效控制,并获得恒定的器件开关频率。利用电压矢量组所具有的对称性,对积分获得的交流电动机磁链幅值和位置角的误差进行校正。该方法可以明显减少感应电动机定子磁链、电磁转矩和电流的波动,而转矩的快速响应仍能保持。具有鲁棒性强、开关频率恒定的优点。仿真结果验证了该方法的有效性。

关键词：直接转矩控制交流感应电机磁链观测器离散空间矢量调制恒定开关频率

甲午前后的报刊地理、新闻呈现与读者阅读的回想

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学术月刊 2018年第12期50卷 153-165页

作者：蒋建国华南理工大学新闻与传播学院教授博士生导师广东广州510641

甲午海战是一个划时代的历史事件,它直接动摇了清廷的统治基础,在士绅社会产生极大的影响。士绅的阅报记录中夹杂了对时局的看法,通过报刊,他们与外部世界建立了"意义之网",对时局、对"他者"充满着想象与关切,报纸拉近了他们与新闻事件... 详细信息

甲午海战是一个划时代的历史事件,它直接动摇了清廷的统治基础,在士绅社会产生极大的影响。士绅的阅报记录中夹杂了对时局的看法,通过报刊,他们与外部世界建立了"意义之网",对时局、对"他者"充满着想象与关切,报纸拉近了他们与新闻事件的"距离",让他们体验到新闻所产生的巨大影响,从而加深了对甲午海战的认知,对国家和民族的命运有着更为深切的忧患意识。从这个意义上看,甲午时期读者的读报活动,与政治危机、思想启蒙和社会变革运动密不可分。

关键词：甲午时期报刊阅读影响

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晚清书院读报活动与时务新知的传播

学术月刊 2017年第4期49卷 167-177页

作者：蒋建国华南理工大学新闻与传播学院教授广州510006

晚清以降,教会书院在引入西学和传播"世界知识"的过程中起着先导作用。传教士将教会书院作为传教事业和传媒资源的重要组成部分,客观上促进了新式报刊在教会书院的组织化传播。维新前后,随着一些地方大员对书院西学教育和报刊阅读的重视... 详细信息

晚清以降,教会书院在引入西学和传播"世界知识"的过程中起着先导作用。传教士将教会书院作为传教事业和传媒资源的重要组成部分,客观上促进了新式报刊在教会书院的组织化传播。维新前后,随着一些地方大员对书院西学教育和报刊阅读的重视,报刊作为思想纸和知识纸的价值被许多书院师生所体认。书院师生的读报活动具有公共与私人阅读相结合的特点,尤其是一些经学大师在书院的读报活动,起到了引领风气和改变知识架构的作用。书院规章对读报与评报的制度性约束,有利于学生了解时政、开拓视野、讲求新学;报刊、书院与学会的互动,则进一步推动了书院师生思想观念的转变。因此,探究晚清书院报刊阅读的发展历程,对于进一步认识新式报刊对书院师生"知识仓库"和"思想世界"的影响有重要价值。

关键词：晚清书院报刊阅读影响

一种新型基于双闭环PID控制的SVC控制系统研究

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系统仿真学报 2007年第8期19卷 1803-1806,1868页

作者：黄黎芬姜建国上海交通大学电气工程系上海200030

基于瞬时无功功率理论和双闭环PID控制构架,设计了一种新型的FC-TCR型SVC控制系统。为实时补偿电网中瞬时无功功率的变化,采用dq同步旋转坐标变换方法,精确检测系统功率,有效克服电网电压波形畸变给p、q运算方法带来的误差;采用双闭环PI... 详细信息

基于瞬时无功功率理论和双闭环PID控制构架,设计了一种新型的FC-TCR型SVC控制系统。为实时补偿电网中瞬时无功功率的变化,采用dq同步旋转坐标变换方法,精确检测系统功率,有效克服电网电压波形畸变给p、q运算方法带来的误差;采用双闭环PID控制结构,内环为电压调节,外环为功率因数校正,使SVC装置能同时达到功率因数校正和改善电压的目的。仿真研究结果表明,此新型SVC控制系统对稳定和抑制电压波动,提高功率因数,具有响应快、精度高的特点。

关键词： SVC 瞬时无功功率 dq转换法双闭环PID控制

Effect of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral infarction

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World Journal of Psychiatry 2024年第8期14卷 1190-1198页

作者： Fei-Fei Liang Xiao-Xia Liu jiang-Hong Liu Yang Gao jian-guo Dai Zi-Hui Sun Department of Geriatrics Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina The Fourth Ward Zhangjiakou Infectious Disease HospitalZhangjiakou 075000Hebei ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina Department of General Medicine Zhangjiakou First Hospital in Hebei ProvinceZhangjiakou 075000Hebei ProvinceChina

BACKGROUND The aging of the population has become increasingly obvious in recent years,and the incidence of cerebral infarction has shown an increasing trend annually,with high death and disability *** To analyze the effects of infarct location and volume on cognitive dysfunction in elderly patients with acute insular cerebral *** Between January 2020 and December 2023,we treated 98 cases of elderly acute insula,patients with cerebral infarction in the cerebral infarction acute phase(3-4 weeks)and for the course of 6 months in Montreal Cognitive Assessment Scale(MoCA)for screening of ***,58 and 40 patients were placed in the cognitive impairment group and without-cognitive impairment group,*** patients with cerebral infarction,magnetic resonance imaging was used to screen and clearly analyze the MoCA scores of two groups of patients with different infarctions,the relationship between the parts of the infarction volume,and analysis of acute insula cognitive disorder in elderly patients with cerebral RESULTS The number of patients with cognitive impairment in the basal ganglia and thalamus was significantly higher than that without cognitive impairment(P<0.05).The total infarct volume in the cognitive impairment group was higher than that in the non-cognitive impairment group,and the difference was statistically significant(P<0.05).The infarct volumes at different sites in the cognitive impairment group was higher than in the non-cognitive impairment group(P<0.05).In the cognitive impairment group,the infarct volumes in the basal ganglia,thalamus,and mixed lesions were negatively correlated with the total MoCA score,with correlation coefficients of-0.67,-0.73,and-0.77,*** In elderly patients with acute insular infarction,infarction in the basal ganglia,thalamus,and mixed lesions were more likely to lead to cognitive dysfunction than in other areas,and patients with large infarct volumes were more like

关键词： Elderly Acute insular infarction Infarction site Cognitive impairment Infarction volume