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Chinese Chemical Letters 2009年第2期20卷 175-177页

作者： Ting Ting Li Ling Zhang Zhe shan quan Hai Bo Zhu Hu Ri Piao Key Laboratory of Natural Resources and Functional Molecules of the Changbai Mountain Affiliated Ministry of Education Yanbian University College of Pharmacy Yanji 133000 China Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

In an attempt to search for more potent positive inotropic agents, a series of 1-（benzylamino）-3-（4,5-dihydro[ 1,2,4]trizaolo[4,3- a]quinolin-7-yloxy）propan-2-ol derivatives was synthesized in four steps using 6-hydroxy-3,4-dihydro-2（1H）-quinolinone as a starting material, and their positive inotropic activities were evaluated by measuring the coronary blood flow （CBF） and the left ventricular pressure （LVP） followed by calculating the rate of pressure development （dp/dtmax values） in the preparation of rat Langendorff＇s heart. Three compounds （5d, 5g, 5j） showed favorable activities, among which 5g was shown the most potent with dp/dtmax value of 9.7% and CBF value of 17.8% at a concentration of 1×10^-5 mol/L in our in vitro study.

关键词： 3,4-Dihydrotrizaolo[4,3-a]quinoline Positive inotropic activity Synthesis

Characteristics Analysis of Extreme Circulation at 500 hPa of Height Field in Eurasian Region during Recent 20 Years

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Meteorological and Environmental Research 2013年第11期4卷 12-15,21页

作者： quan shan Zhejiang Meteorological Service Center

[ Objective] The research aimed to analyze extreme circulation characteristics at 500 hPa of height field in Eurasian region in recent 20 years. [ Method ] Based on NCEP/NCAR reanalysis daily data at 500 hPa of height field from 1961 to 2009 of Eurasia （15° -80° N, 40° -150° E）, seasonal and monthly change situations of extreme circulation in Eurasia were studied by the method of climatologically equally likely intervals （ CE- Ll）. [Result] Growth rate of extremely low circulation increased in Eurasia in the last 20 years, but the rise amplitude was smaller. In the middle of China and Mongolia, grow rate change of extremely low circulation was the smallest. The growth rates of extremely high circulation in spring, au- tumn and winter gradually decreased as latitude rose. The maximum growth rate of extremely high circulation in summer was in Qinghai -Tibet Plat- eau, which corresponded with the climate characteristics of summer subtropical high going northward and then retreating southward. By contrasting the growth rates of extremely low and high circulation, it was clear that the growth rate of high circulation was higher than that of the low circulation. [Conusion] The research could be as a reference for studying change characteristics of the extreme climate event in China.

关键词： Extreme circulation 500 hPa of height field CELl Growth rate China

Experimental study on temperature fluctuations on plate surface induced by coaxial-jet flow

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Nuclear Science and Techniques 2024年第5期35卷 139-153页

作者： Xue-Yao Xiong Zun-quan Liu Guo-Yan Zhou Xing Luo shan-Tung Tu Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science and TechnologyShanghai 200237China Institute of Thermodynamics Gottfried Wilhelm Leibniz University Hannover30823 GarbsenGermany

In nuclear reactors,temperature fluctuations of fluids may cause fatigue damage to adjacent structures;this is referred to as thermal *** on thermal striping in the upper plenum has mainly focused on fluid *** experimental studies have been reported on solid structures in a fluid field with a coaxial *** study entailed an experimental study of the temperature fluctuations in the fluid and on a plate surface caused by a coaxial *** temperature fluctuations of the fluid and plate surfaces located at different heights were *** cause of the temperature fluctuation was analyzed using a transient temperature *** results show that the mixing of the hot and cold fluids gradually becomes uniform in the positive axial *** average surface temperatures tended to be *** the jet reaches the plate surface,the swing of the jet center,contraction and expansion of the cold jet,and changes in the jet shape result in temperature *** intensity of the temperature fluctuation was affected by the *** attention should be paid when the plate is located at a lower height,and between the hot and cold-fluid nozzles.

关键词： Temperature fluctuation Thermal striping Coaxial jet Thermal mixing The upper plenum of nuclear reactor

Temporal Variations in Sea of Clouds and Their Relation with Meteorological Factors in Yandang Mountains

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Meteorological and Environmental Research 2016年第2期7卷 15-17页

作者： shan quan Liang Xiaoni Zhejiang Meteorological Service Center

Based on data of meteorological elements in the meteorological station in North Yandang Mountains during 1960- 2013,temporal variations in days of sea of clouds over Yandang Mountains in nearly 50 years and their relation with air temperature,precipitation,relative humidity and wind speed were analyzed. The results showed that annual average days of sea of clouds over Yandang Mountains were 164. 92 d,and the maximum and minimum were 215 and 58 d,so there was a big difference between various years. The days of sea of clouds were the most in spring,and average days of sea of clouds（ average days of sea of clouds with low cloud cover ≥80%） were 50. 89 d（ 32. 77 d）,while they were the least in autumn. There was an obvious positive correlation between the days of sea of clouds and relative humidity. Precipitation occurred the day before or on the day when sea of clouds with low cloud cover ≥80% formed. On the day when sea of clouds with low cloud cover ≥80% appeared,average relative humidity was ≥80%,and average wind speed was ≤4. 5 m/s.

关键词： Yandang Mountains Sea of clouds Changing features Meteorological factors China

When quantum dots meet blue phase liquid crystal elastomers:visualized full-color and mechanically-switchable circularly polarized luminescence

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Light(Science & Applications) 2024年第6期13卷 1210-1220页

作者： shan Li Yuqi Tang Qingyan Fan Ziyuan Li Xinfang Zhang Jingxia Wang Jinbao Guo quan Li Key Laboratory of Carbon Fibers and Functional Polymers Ministry of Educationand College of Materials Science and EngineeringBeijing University of Chemical Technology100029BeijingChina Institute of Advanced Materials and School of Chemistry and Chemical Engineering Southeast UniversityNanjing211189China Materials Science Graduate Program Kent State UniversityKentOH44242USA CAS Key Laboratory of Bio-Inspired Materials and Interfacial Sciences Technical Institute of Physics and ChemistryChinese Academy of Sciences100190BeijingChina

Polymer-based circularly polarized luminescence(CPL)materials with the advantage of diversified structure,easy fabrication,high thermal stability,and tunable properties have garnered considerable ***,adequate and precise tuning over CPL in polymer-based materials remains challenging due to the difficulty in regulating chiral ***,visualized full-color CPL is achieved by doping red,green,and blue quantum dots(QDs)into reconfigurable blue phase liquid crystal elastomers(BPLCEs).In contrast to the CPL signal observed in cholesteric liquid crystal elastomers(CLCEs),the chiral 3D cubic superstructure of BPLCEs induces an opposite CPL ***,this effect is entirely independent of photonic bandgaps(PBGs)and results in a high glum value,even without matching between PBGs and the emission bands of ***,the lattice structure of the BPLCEs can be reversibly switched via mechanical stretching force,inducing on-off switching of the CPL signals,and these variations can be further fixed using dynamic disulfide bonds in the ***,the smart polymer-based CPL systems using the BPLCEs for anti-counterfeiting and information encryption have been demonstrated,suggesting the great potential of the BPLCEs-based CPL active materials.

关键词： circular quantum crystal

一维固定床煤粉富氧燃烧的辐射能流特性与模型分析（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第6期20卷 431-446页

作者： Shi-quan shan Zhi-jun ZHOU Zhi-hua WANG Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

目的:1.从辐射能利用角度出发,探究一维固定床煤粉富氧燃烧的辐射能流特性,为固体燃料燃烧能量分质分级转化应用提供参考;2.对比研究半经验模型与人工神经网络模型这两种建模方法,为人工神经网络模型在后续研究中的应用提供参考。创新点... 详细信息

目的:1.从辐射能利用角度出发,探究一维固定床煤粉富氧燃烧的辐射能流特性,为固体燃料燃烧能量分质分级转化应用提供参考;2.对比研究半经验模型与人工神经网络模型这两种建模方法,为人工神经网络模型在后续研究中的应用提供参考。创新点:1.提出燃烧光热能量分级转化的概念,为燃烧光热能量分质分级转化系统提供研究基础;2.从辐射能量利用的角度研究煤粉燃烧的辐射能流特性;3.不局限于实验报告,基于实验数据探究2种建模方法,揭示神经网络模型的优势。方法:1.在一维管式炉反应器上进行实验,探究不同燃烧条件下煤粉富氧燃烧的辐射能流特征;2.基于辐射传热理论,通过半经验模型描述煤粉在固定床中燃烧的辐射能流;3.训练神经网络模型来描述实验结果,通过对比2种方法来揭示神经网络模型在预测结果方面的优势。结论:1.固定床煤燃烧过程中的挥发分及煤烟会降低辐射能;可利用低挥发分燃料以及增大氧浓度来提高火焰辐射能比例。2.较高的燃烧温度是提升燃烧辐射能比例最重要的因素;实践中可以通过采用高热值燃料以及烟气回热等方法来提高燃烧温度。3.多联产半焦燃烧辐射能比例高于原煤;可通过煤热解多联产技术与半焦燃烧光热能量分级利用相结合的方式构成新的煤炭高效清洁利用系统。4.人工神经网络不但可以对实验结果进行建模,还能够很好地预测未知工况结果,因此值得在更多的后续研究中使用。

关键词：辐射能流固定床富氧燃烧人工神经网络能量分质分级转化

Expression of Livin and vascular endothelial growth factor in different clinical stages of human esophageal carcinoma

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World Journal of Gastroenterology 2008年第37期14卷 5749-5754页

作者： Li Chen Guo-Sheng Ren Fan Li shan-quan Sun Department of Thoracic Surgery the First AffiliatedHospital of Chongqing Medical University Chongqing 400016China Department of General Surgery theFirst Affiliated Hospital of Chongqing Medical UniversityChongqing 400016 China Anatomy institution of Chongqing MedicalUniversity Chongqing 400016 China

AIM： To investigate the role of Livin and vascular endothelial growth factor （VEGF） in human esophageal carcinoma, and analyze its relationship to clinical stages.METHODS： Expression of Livin in fresh esophageal cancer tissues was detected by immunohistochemistry （IHC）, Western blotting and reverse transcriptasepolyrnerase chain reaction （RT-PCR）, and VEGF by Western blotting and RT-PCR. All statistical analyses were performed by SPSS version 11.0. RESULTS： Livin positivity was also significantly correlated with tumor stages, increasing with tumor progression. Expression of Livin and VEGF increased with the process of esophageal carcinoma. In the fourth clinical stage, expression of Livin and VEGF was the most significant. Expression of Livin was positively correlated with VEGF. CONCLUSION： Over-expression of Livin and VEGF contributes to the pathogenesis of esophageal carcinoma.

关键词： Esophageal carcinoma Livin Vascular endothelial growth factor

Constructing energetic covalent organic frameworks with high stability and low sensitivity

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Chinese Chemical Letters 2024年第3期35卷 544-548页

作者： Hui-Min Guo Xiao-Yu Dong shan Wang Qian-You Wang Shuang-quan Zang Henan Key Laboratory of Crystalline Molecular Functional Materials Green Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China

Developing new functional explosives that display high stability,good energy performance,and low sensitivity are one of the key directions of energetic materials *** this work,two-dimensional(2D)Schiff-based energetic covalent organic frameworks(COFs)are prepared based on triaminoguanidine salts with different anions as building *** from the robust covalent bond in 2D extended polygons and strongπ-πinteractions in the eclipsed interlayers,the synthesized energetic COFs showed higher thermal stability and lower mechanical sensitivity than their precursor *** importantly,incorporating triaminoguanidine salts into COFs effectively increase the corrosion resistance to metal under high humidity conditions,which is due to the imine moieties in COFs functioning asπacceptors and offering strong bonding with metallic *** work provides a new pathway for the development of high-performance energetic materials.

关键词： Covalent organic frameworks Energetic materials High thermal stability Low sensitivity Corrosion resistance

Modeling and optimum operating conditions for FCCU using artificial neural network

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Journal of Central South University 2015年第4期22卷 1342-1349页

作者：李全善李大字曹柳林 Department of Automation Beijing University of Chemical Technology

A self-organizing radial basis function(RBF) neural network(SODM-RBFNN) was presented for predicting the production yields and operating optimization. Gradient descent algorithm was used to optimize the widths of RBF neural network with the initial parameters obtained by k-means learning method. During the iteration procedure of the algorithm, the centers of the neural network were optimized by using the gradient method with these optimized width values. The computational efficiency was maintained by using the multi-threading technique. SODM-RBFNN consists of two RBF neural network models: one is a running model used to predict the product yields of fluid catalytic cracking unit(FCCU) and optimize its operating parameters; the other is a learning model applied to construct or correct a RBF neural network. The running model can be updated by the learning model according to an accuracy criterion. The simulation results of a five-lump kinetic model exhibit its accuracy and generalization capabilities, and practical application in FCCU illustrates its effectiveness.

关键词： radial basis function(RBF) neural network self-organizing gradient descent double-model fluid catalytic cracking unit(FCCU)

Neuroprotective effect of baicalin on focal cerebral ischemia in rats

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Neural Regeneration Research 2018年第12期13卷 2129-2133页

作者： Jiong Dai Yong-Ming Qiu Zheng-Wen Ma Guo-Feng Yan Jing Zhou shan-quan Li Hui Wu Yi-Chao Jin Xiao-Hua Zhang Department of Neurosurgery Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai China Department of of Laboratory Animal Science Shanghai Jiao Tong University School of Medicine Shanghai China

Baicalin, a flavonoid compound from the root of the herb Scutellaria baicalensis Georgi, has been widely used to treat patients with inflammatory disease. The aim of this study was to assess the efficacy of baicalin in a rat model of focal cerebral ischemia. Adult male Sprague-Dawley rat models of cerebral artery occlusion were established and then randomly and equally divided into three groups： ischemia（cerebral ischemia and reperfusion）, valproic acid（cerebral ischemia and reperfusion ＋ three intraperitoneal injections of valproic acid; positive control）, and baicalin（cerebral ischemia and reperfusion ＋ intraperitoneal injection of baicalin for 21 days）. Neurological deficits were assessed using the postural reflex test and forelimb placing test at 3, 7, 14, and 21 days after ischemia. Rat cerebral infarct volume was measured using 2,3,5-triphenyltetrazolium chloride（TTC） staining method. Pathological change of ischemic brain tissue was assessed using hematoxylin-eosin staining. In the baicalin group, rat neurological function was obviously improved, cerebral infarct volume was obviously reduced, and the pathological impairment of ischemic brain tissue was obviously alleviated compared to the ischemia group. Cerebral infarct volume was similar in the valproic acid and baicalin groups. These findings suggest that baicalin has a neuroprotective effect on cerebral ischemia.

关键词： cerebral ischemia neurological function cerebral infarct volume middle cerebral artery occlusion rat model valproic acid neural regeneration