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A New Approach to the Synthesis of Bergapten

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Chemical Research in Chinese Universities 2022年第6期38卷 1492-1496页

作者： CAI Xiaoqing JI Dongxin LIU Jiageng hu maolin JIN Zhimin College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035P.R.China College of Pharmaceutical Sciences Zhejiang University of TechnologyHangzhou310014P.R.China Department of Chemistry Zhejiang UniversityHangzhou310027P.R.China

In this study, bergapten was synthesized in a yield of 55% from phloroglucinol as starting material, via a novel approach including monomethylation, Hoesch reaction, acetylation, deacetoxylation, Pechmann condensation and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone(DDQ) dehydrogenation. With the adoption of the acetylation of enol tautomer, the deacetoxylation and the DDQ dehydrogenation, the novel approach differs greatly from the processes reported previously, though the starting material was the same or similar to those used on previous synthetic processes. The newly adopted reaction underwent easily, affording all reactions in high yields, especially acetylation and deacetoxylation and DDQ dehydrogenation in almost quantitative yields, ensuring a final yield higher than those previously reported.

关键词： Bergapten Enol tautomerism Acetylation Deacetoxylation 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)dehydrogenation

Competitive analysis for discrete multiple online rental problems

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Journal of Management Science and Engineering 2018年第3期3卷 125-140页

作者： maolin hu Weijun Xu Hongyi Li Xiaoli Chen School of Mathematical Science Huaiyin Normal UniversityHuai'an 223300China School of Business Administration South China University of TechnologyGuangzhou 510641China Business Administration Faculty The Chinese University of Hong KongHong KongChina CEFMS Hunan UniversityChangsha 410082China School of Internet Finance and Information Engineering Guangdong University of FinanceGuangzhou 510520China

Many actual rental activities present online rental problems with multiple units of assets or equipment whose use can be continuous,separable,or *** online algorithms and competitive analysis,continuous multiple online rental problems have obtained the optimal risk control strategy and the optimal competitive *** multiple online rental problems with discrete assets,first,we present an approximation algorithm for a risk control strategy and the upper bound of the optimal competitive ***,in practical applications,the approximation algorithm of the discrete online problem provides the approximate rental quantities in each period and the solution principle for the approximate competitive ***,we present the approximate optimal rental quantities and the correction algorithm to obtain a better competitive ratio based on the approximation ***,we compare the approximation algorithm with the correction algorithm by real *** findings show that when the approximate solution is used to replace the corrected solution,the resulting approximation error is usually less than the magnitude of 1/ms where m is the total units of certain assets or equipment and s is the price to buy one unit in each period.

关键词： Discrete multiple online rental problem Risk control strategy Online algorithms Competitive ratio

Electrochemical investigation on the interaction of benzene sulfonyl 5-fluorouracil derivatives with double-stranded DNA and G-quadruplex DNA

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Science China Chemistry 2012年第6期55卷 1345-1350页

作者： hu Quan ZHANG KeJun JIN huiLe CHEN XiAn hu maolin WANG Shun Nanomaterials and Chemistry Key Laboratory Wenzhou UniversityWenzhou 325035China Department of Pharmacology School of Basic MedicineHangzhou Normal UniversityHangzhou 310036China

The interaction of double-stranded （ds） and G-quadruplex （G4） DNA with sulfonyl 5-fluorouracil derivatives （5-fluoro-l-（arylsulfonyl） pyrimidine-2,4 （1H,3H）-diones） was investigated in this research, in which Au electrodes modified with ds-DNA or G4-DNAs were used as a working electrode. The investigation showed that the binding affinity with G4-DNA was significantly increased when 5-fluorouracil （5-FU） was modified with arylsulfonyl groups. The presence of strong electron-withdrawing groups on benzene sulfonyl 5-FU greatly enhanced the binding selectivity （kG4-DNA/kds-DNA）. Such results provided new insights into the potential connections between the chemical structure of drug candidates and their anticancer activities.

关键词： anti-tumor activity differential pulse voltammetry double-stranded DNA G-quadruplex DNA 5-fluorouracil derivatives

Degenerate Semilinear Eliptic Equations with Critical Exponent

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Communications in Mathematical Research 1999年第1期 76-84页

作者： hu maolin (Department of Mathematics, Anhui University, Hefei, Anhui, 230039)

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｉｓｐａｐｅｒ，ｗｅａｒｅｉｎｔｅｒｅｓｔｅｄｉｎｔｈｅｅｘｉｓｔｅｎｃｅ，ｎｏｎｅｘｉｓｔｅｎｃｅｏｆｐｏｓｉｔｉｖｅａｎｄｍｕｌｔｉｐｌｅｓｏｌｕｔｉｏｎｓｔｏｔｈｅｐｒｏｂ... 详细信息

§１．ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｉｓｐａｐｅｒ，ｗｅａｒｅｉｎｔｅｒｅｓｔｅｄｉｎｔｈｅｅｘｉｓｔｅｎｃｅ，ｎｏｎｅｘｉｓｔｅｎｃｅｏｆｐｏｓｉｔｉｖｅａｎｄｍｕｌｔｉｐｌｅｓｏｌｕｔｉｏｎｓｔｏｔｈｅｐｒｏｂｌｅｍｏｆｄｅｇｅｎｅｒａｔｅｓｅ...

关键词： Degenerate Equation Critical Exponent Multiplicity of Solutions Positive Solution Nonexistence Result

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离散型两斜率在线租赁问题

系统工程理论与实践 2019年第7期39卷 1680-1689页

作者：胡茂林徐维军淮阴师范学院数学科学学院淮安223300 华南理工大学工商管理学院广州510641

两斜率在线租赁问题是经典的在线租赁问题的一种自然的推广.基于在线租赁问题的研究分为离散时间和连续时间,鉴于已有文献对连续时间情况下两斜率在线租赁问题进行了讨论,本文研究离散时间情况下两斜率在线租赁问题.我们的讨论包括确定... 详细信息

两斜率在线租赁问题是经典的在线租赁问题的一种自然的推广.基于在线租赁问题的研究分为离散时间和连续时间,鉴于已有文献对连续时间情况下两斜率在线租赁问题进行了讨论,本文研究离散时间情况下两斜率在线租赁问题.我们的讨论包括确定性竞争策略和随机性在线策略.关于确定性策略,一个竞争因数为2-[1+(s-1)a]/s的最优策略被给出.对于随机性策略,本文提出了风险均衡策略,并通过竞争分析的方法证明了该策略是唯一最优策略.最后,对两种策略的竞争性能做了分析和讨论·分析和讨论的结果表明:考虑两斜率能改善经典问题的竞争比,考虑离散性能比连续性提高决策效率.

关键词：在线租赁离散型两斜率确定性策略随机性策略

具有粘性的拟线性波动方程整体解的存在性(英文)

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数学进展 2001年第2期30卷 123-132页

作者：胡茂林安徽大学数学系

首先证明了稳定集的估计，并在一定几何条件下，得到了整体解的存在性．

关键词：整体解粘性波动方程稳定集存在性拟线性波动方程

Global Solution for Quasilinear Wave Equations with Viscosity and Nonlinear Perturbation

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Northeastern Mathematical Journal 2001年第3期17卷 289-300页

作者：胡茂林 Department of Mathematics Anhui University Hefei 230039

In this paper we prove the global existence and decay of solutions to the initial-boundary value problem for the quasilinear wave equations with viscosity and a nonlinear perturbation.

关键词： global solution wave equation viscosity nonlinear perturbation

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局内车辆选线问题的比较策略及其竞争比分析

宁夏大学学报（自然科学版） 2005年第3期26卷 207-210页

作者：胡茂林固原师范高等专科学校数学系宁夏固原756000

对现实物流配送中遇到的无法预测的线路堵塞问题,建立了具有堵塞点的局内车辆选线问题的数学模型,并分别介绍了局内运输车辆调度的贪婪策略和复位策略.在全面分析了这2种基本策略在竞争性能上的优劣之后,给出了比较策略及其算法模型.最... 详细信息

对现实物流配送中遇到的无法预测的线路堵塞问题,建立了具有堵塞点的局内车辆选线问题的数学模型,并分别介绍了局内运输车辆调度的贪婪策略和复位策略.在全面分析了这2种基本策略在竞争性能上的优劣之后,给出了比较策略及其算法模型.最后,讨论了该策略的竞争性能.结果表明,比较策略实现了对局内运输车辆的优化调度.

关键词：局内问题贪婪策略复位策略比较策略竞争比

Kinetics and mechanism of the reaction between thiourea and iodate in unbuffered medium

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Science China Chemistry 2004年第6期47卷 480-487页

作者： WANG Shun1,2, LIN Juanjuan1, CHEN Fan1, hu maolin1, hu Xingen1, HAN Yiping1 & GAO Qingyu2 1.Department of Chemistry and Material Science, Wenzhou Normal College, Wenzhou 325027, China 2. College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221008, China Department of Chemistry and Material Science Wenzhou Normal College Wenzhou China College of Chemical Engineering China University of Mining and Technology Xuzhou China

The reaction between iodate and thiourea has been studied in an unbuffered acidic medium. In excess iodate the reaction shows not only oligooscillations in pH, Pt potential and the concentration of iodide ion, [I?], but also an initial induction period which has the linear relation with initial pH. At the end of the induction period, [I?] decreases sharply and a yellow coloration (due to iodine) appears transiently. While in excess thiourea iodine is produced and finally con- sumed, leaving milky deposits (due to sulfur) at the end of the reaction. The induction period from the start of the reaction to the maximum of [I2] is also directly proportional to initial pH. A 14-step mechanism, including a H+-mediated preequalibrium, Dusman reaction, iodine-sulfur reactions and sulfur-sulfur reactions, is proposed. Computer simulations using this mechanism give good agreement with experiments.

关键词： oligooscillations, pH dynamics, thiourea, iodate, complex reaction mechanism, dynamic simulation.