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豆叶九里香的化学成分研究

中国中药杂志 2017年第10期42卷 1916-1921页

作者：陈月梅曹南开屠鹏飞姜勇北京大学医学部天然药物及仿生药物国家重点实验室北京100191

利用开放的硅胶、ODS和Sephadex LH-20柱色谱及半制备型高效液相等色谱方法对豆叶九里香Murraya euchrestifolia中的化学成分进行分离纯化,结合理化性质和MS,NMR等波谱学数据对化学结构进行解析。结果从豆叶九里香95%乙醇提取物的二氯... 详细信息

利用开放的硅胶、ODS和Sephadex LH-20柱色谱及半制备型高效液相等色谱方法对豆叶九里香Murraya euchrestifolia中的化学成分进行分离纯化,结合理化性质和MS,NMR等波谱学数据对化学结构进行解析。结果从豆叶九里香95%乙醇提取物的二氯甲烷部位共分离并鉴定了18个化合物,分别为sakuranetin(1),eriodictyol-7,4'-dimethyl ether(2),isosakuranetin(3),5-hydroxy-7,4'-dimethoxyflavanone(4),eriodictyol-7-methyl ether(5),lichexanthon(6),5,6,7-trimethoxycoumarin(7),5-hydroxy-6,8-dimethoxycoumarin(8),8-hydroxy-6-methoxy-3-n-pentylisocoumarin(9),ethyl caffeate(10),4-hydroxy-3,5-dimethoxycinnamic acid ethyl ester(11),methyl 3-(5'-hydroxyprenyl)-coumarate(12),(E)-coniferol(13),β-hydroxypropiovanillone(14),3-hydroxy-7,8-didehydro-β-ionone(15),3β-hydroxy-5α,6α-epoxy-7-megastigmen-9-one(16),grasshopper ketone(17),4-hydroxy-3,5-dimethoxybenzaldehyde(18),其中化合物1~15和18为首次从九里香属植物中分离得到,16和17为首次从该植物中分离得到。

关键词：豆叶九里香化学成分黄酮类香豆素苯丙素

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水力压裂多裂缝扩展的近场动力学模拟

科学技术与工程 2022年第29期22卷 12806-12812页

作者：曹楷楠胡志明端祥刚常进中国科学院大学工程科学学院北京100049 中国科学院渗流流体力学研究所廊坊065007 中国石油勘探开发研究院北京100083

为研究页岩水力压裂中多裂缝扩展规律,采用一种结合近场动力学和有限差分法的方法对水力压裂问题建立流固耦合模型。使用近场动力学建立单相固体平面应力问题模型,采用达西定律描述裂隙内流体和基质内流体的流动,对流动区域以损伤程度... 详细信息

为研究页岩水力压裂中多裂缝扩展规律,采用一种结合近场动力学和有限差分法的方法对水力压裂问题建立流固耦合模型。使用近场动力学建立单相固体平面应力问题模型,采用达西定律描述裂隙内流体和基质内流体的流动,对流动区域以损伤程度进行划分,并通过损伤值标定对应的渗透率,采用有限差分法求解得到渗流场压力分布,依据有效应力原理得到流固耦合模型。设计了不同间距的两条裂缝,交错的两条裂缝与三条裂缝同时扩展的模拟实验。结果表明,由于缝间干扰,两条裂缝扩展时会发生反向偏转,并且随着裂缝间距减小,偏转越明显;对于两条交错裂缝,随着裂缝扩展,会互相吸引;对于三条裂缝扩展的情况,中间裂缝的扩展会受到限制。可见需要适当增大水力裂缝间距,减小缝间干扰的影响。

关键词：近场动力学水力压裂多裂缝扩展

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上颌前磨牙根管解剖形态特点的研究进展

中华老年口腔医学杂志 2017年第5期15卷 314-319页

作者：史志芸胡楠曹均凯解放军总医院老年口腔科硕士生北京100853 解放军总医院口腔科主任医师副教授北京100853

上颌前磨牙是根管治疗中最复杂的一组牙,其根管解剖形态变异较大,人们寻求了诸多方法对其根管形态进行研究,每种方法各有利弊,本文就上颌前磨牙根管解剖形态的研究进行综述,为临床开展上颌前磨牙根管治疗提供理论基础。

关键词：上颌前磨牙根管形态根管系统

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靶向瞬时受体电位通道天然调节剂的研究进展

药学学报 2017年第5期52卷 673-684页

作者：曹南开吕海宁卫宁宁李军屠鹏飞王克威姜勇北京大学药学院天然药物与仿生药物国家重点实验室北京100191 青岛大学药学院山东青岛266021

超家族瞬时受体电位(transient receptor potential,TRP)通道是存在于细胞膜上的非选择性阳离子通道,28个成员分为7个亚家族,广泛分布于人体的组织器官内,作为生物感受器参与调节视觉、听觉、味觉、痛觉和触觉等功能。到目前为止,从自... 详细信息

超家族瞬时受体电位(transient receptor potential,TRP)通道是存在于细胞膜上的非选择性阳离子通道,28个成员分为7个亚家族,广泛分布于人体的组织器官内,作为生物感受器参与调节视觉、听觉、味觉、痛觉和触觉等功能。到目前为止,从自然界中已发现TRP通道天然调节剂有100余种,来源于70余种动植物。本文系统综述了这些天然调节剂的来源、结构类型及其作用特点和机制,旨在为靶向TRP通道天然调节剂的发现及创新药物研究提供参考。

关键词：瞬时受体电位通道天然调节剂 TRPV TRPA TRPM TRPC 辣椒素

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期 223-241页

作者： WEI Xinyi ZHANG nan ZHANG Zhaoli cao Xiaoling YUAN Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

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An effective method to determine bedding system insulation based on measured data

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Building Simulation 2023年第1期16卷 121-132页

作者： nan Zhang Bin cao Yingxin Zhu Department of Building Science School of ArchitectureTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control(Tsinghua University) Beijing 100084China Key Laboratory of Eco Planning&Green Building Ministry of Education(Tsinghua University)Beijing 100084China

The thermal environment is an essential factor that affects sleep *** many circumstances,the bed microenvironment is more important than the ambient environment because of the large covered area of the human body and the close contact between the bedding system and the human *** main objective of this research is to establish an effective method to determine bedding system insulation.A thermal manikin was used in the measurement of bedding system *** different types of quilts,which were filled with cotton,polyester and duvet respectively,were chosen to be *** total ten different quilts with different materials and weights were involved in the *** regular arrangements of covers were chosen with coverage rates of 94.1%,85.9%,70.6%,and 54.4%to test.A total of 64 bedding systems were tested to build an effective method to determine the bedding system *** the basis of test data,the change of bedding system insulation with coverage was found to be *** fitting was applied to establish an insulation evaluation method for bedding system *** addition,the effects of quilt cover and sleepwear on bedding system insulation were discussed and thermal insulation increment caused by quilt cover and sleepwear were *** relationships between neutral indoor temperature and weight per unit area of the quilt for different coverage rates have been quantified based on existing subject *** research provides an effective method to determine bedding system insulation,which can be widely used in thermal comfort research and HVAC system design.

关键词： sleep environment bedding system thermal insulation thermal comfort

Efficacy of mesenchymal stem cells in the treatment of gastrointestinal malignancies

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World Journal of Gastrointestinal Oncology 2020年第4期12卷 365-382页

作者： Jian-nan Li Wei Li Lan-Qing cao Ning Liu kai Zhang Department of General Surgery The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina Department of Pathology The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina Department of Central Laboratory The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina

Mesenchymal stem cells(MSCs),which are a kind of stem cell,possess an immune privileged nature,tumour homing features,and multi-lineage differentiation *** have been studied in many fields,such as tissue engineering,nervous system diseases,and cancer *** recent years,an increasing number of researchers have focused on the effects of MSCs on various kinds of ***,the concrete anticancer efficacy of MSCs is still ***(GI)malignancies are the major causes of cancerrelated death *** interactions of MSCs and GI cancer cells in specific conditions have attracted increasing *** this review,we introduce the characteristics of MSCs and analyse the effects of MSCs on GI malignancies,including gastric cancer,hepatoma,pancreatic cancer,and colorectal *** addition,we also provide our perspectives on why MSCs may play different roles in GI malignancies and further research directions to increase the treatment efficacy of MSCs on GI malignancies.

关键词： Mesenchymal stem cells Gastrointestinal malignancies Gastric cancer Hepatoma Pancreatic cancer Colorectal cancer

Testing the distance-duality relation with a combination of cosmological distance observations

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Research in Astronomy and Astrophysics 2011年第10期11卷 1199-1208页

作者： Shuo cao nan Liang Department of Astronomy Beijing Normal University Beijing 100875 China Center for High Energy Physics Peking University Beijing 100871 China

We propose an accurate test of the distance-duality （DD） relation, η = DL（z）（1 ＋ z）^-2/DA（z） = 1 （where DL and DA are the luminosity distances and angular diameter distances, respectively）, with a combination of cosmological observational data of Type Ia Supernovae （SNe Ia） from the Union2 set and the galaxy cluster sample under an assumption of the spherical model. In order to avoid bias brought on by redshift non-coincidence between observational data and to consider redshift error bars of both clusters and SNe Ia in the analysis, we carefully choose the SNe Ia points which have the minimum acceptable redshift difference of the galaxy cluster sample （│△Z│min = σz,SN ＋σz,cluster）. By assuming η to be a constant and defined as functions of the redshift parameterized by six different expressions, we find that there exists no observable evidence for variations in the DD relation based on the collected data, since related statistical tests are well satisfied within the 1σ confidence level for most cases. Further, considering different values of △z as constraints, we also find that the choice of △z may play an important role in this model-independent test of the DD relation for the spherical sample of galaxy clusters.

关键词： distance scale -- galaxies clusters general -- supernovae general

Distance-covariance-based tests for heteroscedasticity in nonlinear regressions

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Science China Mathematics 2021年第10期64卷 2327-2356页

作者： kai Xu Mingxiang cao School of Mathematics and Statistics Anhui Normal UniversityWuhu 241002China

In this paper,we propose a new numerical scheme for the coupled Stokes-Darcy model with the Beavers-Joseph-Saffman interface *** use the weak Galerkin method to discretize the Stokes equation and the mixed finite element method to discretize the Darcy equation.A discrete inf-sup condition is proved and the optimal error estimates are also *** experiments validate the theoretical analysis.

关键词： bootstrap distance covariance heteroscedasticity testing nonlinear regression test of independence