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Escobar-Lichnerowicz-Reilly type eigenvalue estimate for the weighted p-Laplacian on manifolds with integral Ricci curvature

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Acta Mathematica Sinica,English Series 2025年

作者： yong tao LIU School of Mathematics and Statistics Ningxia University

Under the assumption of integral m-Bakry-émery Ricci curvature, we give an Escobar-LichnerowiczReilly type eigenvalue estimate for the weighted p-Laplacian on compact smooth metric measure spaces with or without boundaries. This conclusion is a generalization and improvement of Wang-Li’s result in the case of integral Bakry-émery Ricci curvature, and of Seto-Wei’s one to the compact metric measure space setting. Our main tools are the weighted p-Bochner formula and the weighted p-Reilly formula.

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茵陈挥发油的超临界CO_2萃取法与水蒸气蒸馏法提取的比较

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分析测试学报 2003年第2期22卷 84-86页

作者：张永明陶玲黄际薇中山大学附属第三医院药剂科广东广州510630

采用超临界CO2 萃取法与水蒸气蒸馏法从茵陈中提取挥发油 ,用GC -MS法测定其化学成分和相对含量 ,对两种提取方法所得的挥发油进行比较 ,水蒸气蒸馏法提取茵陈挥发油的产率为0.03 %(w) ,主要成分为匙叶桉油烯醇、吉玛烯D、反式_石竹烯、... 详细信息

采用超临界CO2 萃取法与水蒸气蒸馏法从茵陈中提取挥发油 ,用GC -MS法测定其化学成分和相对含量 ,对两种提取方法所得的挥发油进行比较 ,水蒸气蒸馏法提取茵陈挥发油的产率为0.03 %(w) ,主要成分为匙叶桉油烯醇、吉玛烯D、反式_石竹烯、2,4_戊二炔苯、β_金合欢烯等;超临界CO2 萃取法提取的产率为0.15 %(w) ,主要成分为百里酚、β_红没药烯、2_异丙基_4_甲基_1_甲氧基苯、异百里酚、2_特丁基_4_(2,4,4_三甲基戊基)苯酚、β_杜松烯等。

关键词：菌陈挥发油超临界流体萃取水蒸气蒸馏法 GC-MS

GF(q)上广义自缩减生成器的一种概率模型

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信息工程大学学报 2007年第1期8卷 38-42,86页

作者：明永涛刘文芬信息工程大学信息工程学院河南郑州450002

建立了GF(q)上广义自缩减生成器的概率模型,分析了其输出序列的性质,得到了输出序列与原序列及经过组合之后的序列之间的符合率表达式,据此可以从概率角度对该生成器进行得失分析,并为对该生成器的攻击提供一定的理论依据。

关键词：钟控序列广义自缩减序列概率模型符合率

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-Xia tao Kai-ming Mo Xu Chen Shu-Hua Zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Modular assembly of complex C-alkyl glycoside enabled via cooperative NHC and photoredox catalysis

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Science China Chemistry 2025年

作者： Rui-Qiang Jiao ming Li Xi Chen Mei-Ze Xu Tian Ding Xiao-Ping Gong Zhuo-Mei Li Xue-Yuan Liu yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou University College of Chemistry and Chemical Engineering Northwest Normal University

C-Alkyl glycosides are found in natural products and are indispensable in drug development programs,owing to their diverse range of medicinal ***-component reactions involving glycosyl radical addition are well documented and proved efficient for the C-alkyl glycosides ***,multicomponent reactions for the rapid and controllable construction of structurally diversified C-alkyl glycosides in a single step remains a significant challenge due to the issues associated with balancing reactivity,compatibility,and ***,we report an NHC and photoredox co-catalyzed three-component method to access complex and valuable C-alkyl *** protocol exhibits broad substrate scope and excellent chemoand ***,nine types of sugars are compatible with this *** addition,the generality of this catalytic strategy was further highlighted by the potential for scalable production,the feasibility of further modifications of the products and its successful application in the late-stage functionalization of pharmaceutical skeletons.

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半边铁角蕨化学成分研究

中国药学杂志 2017年第2期52卷 100-104页

作者：刘晖晖于永明张涛张秋博杨峻山邹忠梅华润三九医药股份有限公司广东深圳518110 中国医学科学院北京协和医学院药用植物研究所北京100193

目的研究半边铁角蕨(Asplenium unilaterale Lam.)全草化学成分。方法全草采用甲醇提取,利用硅胶、Sephadex LH-20、半制备HPLC等色谱技术方法进行分离纯化,根据波谱数据对化合物进行结构鉴定。结果分离并鉴定了15个化合物,分别为(Z)-4-... 详细信息

目的研究半边铁角蕨(Asplenium unilaterale Lam.)全草化学成分。方法全草采用甲醇提取,利用硅胶、Sephadex LH-20、半制备HPLC等色谱技术方法进行分离纯化,根据波谱数据对化合物进行结构鉴定。结果分离并鉴定了15个化合物,分别为(Z)-4-(2,6,6-三甲基亚环己-2-烯基)丁-2-醇(1)、淫羊藿次苷B_2(2)、柑橘苷A(3)、6R,9R-3-酮-α-紫罗兰醇-9-O-β-D-吡喃葡萄糖苷(4)、(6S,9R)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡萄糖苷(5)、6-甲基-香豆素(6)、6,7-二羟基-香豆素(7)、gibepyrone D(8)、羽扇豆烷-3-酮(9)、佛来心苷(10)、22,23-二甲基胆甾-5-烯-3-醇(11)、正三十二醇(12)、5-己烷呋喃-2(5H)-酮(13)、托可醌(14)和2,4(1H,3H)-嘧啶二酮(15)。结论化合物1~15均为首次从该属植物中分离得到。

关键词：半边铁角蕨, 紫罗兰酮, 香豆素, (Z)-4-(2, 6, 6-三甲基亚环己-2-烯基)丁-2-醇, 淫羊藿次苷B2, 柑橘苷A

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利用特征矩阵求布尔函数的零化子

信息工程大学学报 2007年第1期8卷 49-52页

作者：冀会芳明永涛刘文芬信息工程大学信息工程学院河南郑州450002

对n元非线性布尔函数的代数次数、特征矩阵和代数免疫度进行了研究,在分析布尔函数的代数次数与特征矩阵关系的基础上,得到了布尔函数的代数免疫度与特征矩阵的关系,并据此给出了寻找布尔函数零化子的一个算法。

关键词：布尔函数特征矩阵零化子代数免疫度

Experimental study of wind loads on gable roofs of low-rise buildings with overhangs

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 300-317页

作者： Peng HUANG Ling tao ming GU yong QUAN i University Shanghai 200092China

Gable roofs with overhangs （eaves） are the common constructions of low-rise buildings on the southeastern coast of China, and they were vulnerable to typhoons from experience. The wind pressure distributions on gable roofs of low-rise buildings are investigated by a series of wind tunnel tests which consist of 99 test cases with various roof pitches, height-depth ratios and width-depth ratios. The block pressure coefficients and worst negative （block） pressure coefficients on different roof regions of low-rise buildings are proposed for the main structure and building envelope, respectively. The effects of roof pitch, height-depth ratio, and width-depth ratio on the pressure coefficients of each region are analyzed in detail. In addition, the pressure coefficients on the roofs for the main structure and building envelope are fitted according to roof pitch, height-depth ratio and width-depth ratio of the low-rise building. Meanwhile, the rationality of the fitting formulas is verified by comparing the fitting results with the codes of different countries. Lastly, the block pressure coefficients and worst negative pressure coefficients are recommended to guide the design of low-rise buildings in typhoon area and act as references for the future＇s modification of wind load codes.

关键词： low-rise building gable roof wind loads wind tunnel test block pressure coefficient load code

Numerical Modelling of Wash Waves Generated by Ships Moving over An Uneven Bottom

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China Ocean Engineering 2023年第1期37卷 145-153页

作者： LI ming-xin YUAN Zhi-ming BAI Xu LI yong-zheng CHENG yong tao Long-bin School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Department of Naval Architecture Ocean and Marine EngineeringUniversity of StrathclydeGlasgow G11XQUK

Unsteady wash waves generated by a ship with constant speed moving across an uneven bottom topography are investigated by numerical simulations based on a Mixed Euler–Lagrange(MEL) method. The transition is accomplished by the ship traveling from the depth h1 into the depth h2 via a step bottom. A small tsunami would be created after this transition. However, the unsteady wave-making resistance induced by this new phenomenon has not been well documented by literature. Therefore, the main purpose of the present study is to quantify the effects of an uneven bottom on the unsteady wash waves and wave-making resistance acting on the ship. An upwind differential scheme is commonly used in the Euler method to deal with the convection terms under free-surface condition to prevent waves in the upstream. Evidently, it cannot be applied to the present problem due to upstream waves generated by the ship would be dampened by the upwind scheme. The central differential scheme provides more accurate results,but it is not unconditionally stable. An MEL method is therefore employed to investigate the upstream wave generated by the ship moving over the uneven bottom. Simulation results show that the hydrodynamic interaction between the ship and the uneven bottom could initiate an upstream tsunami, as well as unsteady wave-making resistance on *** unsteady wave-making resistance oscillates periodically, and the amplitude and period of the oscillations are highly dependent on speed and water depth.

关键词： uneven bottom upstream wave unsteady wave resistance numerical simulation periodic oscillation