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Separation of gibberellin A4 from A4 and A7 mixture by selective complex

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Chinese Chemical Letters 2010年第10期21卷 1206-1208页

作者： Lai wen hu yong Yao Zhang Yun Guo Cong Wang Zhi Min Jin College of Pharmaceutical Sciences Zhejiang University of Technology Hangzhou 310014 China

Gibberellin A4 is effectively separated from mixture of gibberellin A4 and its analogue gibberellin A7, in the form of its crystalline complex with N,N,N＇,N＇-tetramethylethylenediamine. After removing the tetramethy... 详细信息

关键词： Separation Gibberellin A4 Complex

Detection　of　Catecholic　Compounds　with　Field-ampilfied　CZE-Amperometry

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Chemical Research in Chinese Universities 1997年第3期13卷 221-228页

作者： hu Shen, PANG Dai-wen , hu yong-gang , CHENG Jie-ke (Department of Chemistry, Wuhan University, Wuhan, 430072 )

On-column sample stacking technique has been used extensively in capillary zone electrophoresis (CZE) to enhance the sensitivity of the measurements with UV-Vis detection. However, the detection limits for CZE-separation are still limit- ed due to the poor sensitivity of a UV-Vis detector. We incorporated field-amplified sample stacking technique into CZE with amperometric detection. Compared with the conventional electromigration injection , a negative peak of water was observed and a great enhancement of signals was obtained. The results in phosphate buffer with sodium dodecyl sulfate (SDS ) and 2-N-(morpholino) ethane sulphonic acid ( MES ) buffer were compared. Subnanomolar concentration limits for cate- cholamine neurotransmitters (dopamine, norepinephrine , epinephriine) and isopro- terenol were achieved in the 25 um capillary with two or three orders of magnitude lower than those with amperometric detection reported previously.

关键词： Capillary zone electrophoresis Amperometric detection Stacking

New antibacterial depsidones from an ant-derived fungus Spiromastix ***-1

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Chinese Journal of Natural Medicines 2022年第8期20卷 627-632页

作者： GUO Zhi-Kai hu wen-yong ZHAO Li-Xing CHEN Yan-Chi LI Sui-Jun CHENG Ping GE hui-Ming TAN Ren-Xiang JIAO Rui-hua State Key Laboratory of Pharmaceutical Biotechnology Institute of Functional BiomoleculesSchool of Life SciencesNanjing UniversityNanjing 210093China Hainan Key Laboratory of Tropical Microbe Resources Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China Yunnan Key Laboratory of Vaccine Research&Development on Severe Infectious Diseases Institute of Medical BiologyChinese Academy of Medical SciencesKunming 650118China Yunnan Institute of Microbiology Yunnan UniversityKunming 650091China

Six new(1–6)and seven known depsidones(7–13)were isolated from the culture of an ant(Monomorium chinensis)-derived fungus Spiromastix *** structures were elucidated by extensive spectroscopic analysis including high resolution MS,1D and 2D NMR *** new bromide depsidones were obtained through supplementing potassium bromide in the fermentation medium of Spiromastix *** isolated compounds showed various bioactivities against the tested phytopathogenic ***,new bromide compound 4,named spiromastixone S,exhibited the strongest activity against Xanthomonas oryzae *** with a MIC value of 5.2μmol·^L(−1).

关键词： Fungus Spiromastix sp Depsidones Phytopathogenic bacteria Antibacterial

局域浓度调控扩散系数的次氯酸-碘离子-丙二酸系统图灵斑图形成中的反常扩散

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物理学报 2014年第23期63卷 360-366页

作者：胡文勇邵元智中山大学物理科学与工程技术学院广州510275

通过数值模拟及振幅方程解析解方法,从实空间和倒空间分析了受局域浓度扩散系数调控下次氯酸-碘离子-丙二酸反应扩散系统图灵斑图形成的扩散机理.在零扩散系数调节下,斑图形成为典型的菲克扩散;而在负向正向扩散系数调节下,斑图的形成... 详细信息

通过数值模拟及振幅方程解析解方法,从实空间和倒空间分析了受局域浓度扩散系数调控下次氯酸-碘离子-丙二酸反应扩散系统图灵斑图形成的扩散机理.在零扩散系数调节下,斑图形成为典型的菲克扩散;而在负向正向扩散系数调节下,斑图的形成依赖欠扩散和超扩散.图灵系统的浓度稳态振幅对随机初始条件敏感性随局域浓度扩散调控系数k的增大而增加.

关键词：反应扩散系统斑图扩散机理

Research on the Welding Process of 590MPa Grade High Strength Automobile Beam Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 983-986页

作者： ZHANG Wu,hu Xue-wen,LIU yong-gang,YANG Xing-liang,ZHANG Jian (Technological Center,Maanshan Iron & Steel Co.,Ltd.,Maanshan243000,Anhui,China) Maanshan Iron & Steel Co Ltd Ctr Technol Maanshan 243000 Anhui Peoples R China

590 MPa automobile beam steel strips are used mainly to manufacture the longitudinal beam of ***’s welding properties are critical to the safety of *** microstructure and mechanical properties of welding joints processed by CO 2 arc welding with different welding parameters were *** results showed that the welding joints were weak when welding heat input were small and the non metal inclusions were found in the weld joints when welding heat input are *** quality of the welding joints is good enough at 170A of the arc current and 24V of the arc *** the other welding parameters fixed,the incomplete fusion defect occurred in the welding joint with backward welding,but the quality of the welding joint is good with forward welding.

关键词： automobile beam steel CO 2 arc welding welding process

(m,n,k)指派问题的最小费用流模型及其算法

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数学的实践与认识 2017年第18期47卷 162-170页

作者：胡勇文陈国华湖北文理学院机械与汽车工程学院湖北襄阳441053 汽车零部件制造装备数字化湖北省协同创新中心湖北襄阳441053

构造(m,n,k)指派问题的最小费用流模型,并将基于对偶原理的最小费用流的允许边算法求解该模型,提出求解(m,n,k)指派问题的一种算法.算法直接在其对应的网络中保持互补松弛条件不变,通过调整节点势以扩大允许网络从而寻求增广链并进行流... 详细信息

构造(m,n,k)指派问题的最小费用流模型,并将基于对偶原理的最小费用流的允许边算法求解该模型,提出求解(m,n,k)指派问题的一种算法.算法直接在其对应的网络中保持互补松弛条件不变,通过调整节点势以扩大允许网络从而寻求增广链并进行流量增广,直至在网络中得到流量为k的最小费用流,此时非O流边对应(m,n,k)指派问题的最优解.给出了(m,n,k)指派问题的最优解及多重最优解的重要性质,数值试验表明算法有效可行.

关键词： (m,n,k)指派问题最小费用流问题最优解性质互补松弛条件允许边算法

一种SPH应力修正算法及自由表面流中的应用

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计算力学学报 2017年第1期34卷 101-105页

作者：王志超李大鸣胡永文江西省水利科学研究院南昌330029 天津大学水利工程仿真与安全国家重点实验室天津300073

提出了一种SPH应力修正算法,即模型中的拉应力和压应力分别采用不同的插值核函数和状态方程来处理,改善应力稳定性问题。介绍了一种改进的Quintic核函数,用于改善模型中压应力的稳定性。通过增加钟型核函数的光滑长度,改善模型中拉应力... 详细信息

提出了一种SPH应力修正算法,即模型中的拉应力和压应力分别采用不同的插值核函数和状态方程来处理,改善应力稳定性问题。介绍了一种改进的Quintic核函数,用于改善模型中压应力的稳定性。通过增加钟型核函数的光滑长度,改善模型中拉应力的稳定性。采用该应力修正算法模拟了无重力条件下方形液滴的震荡变形过程,对比分析了不同算法的模拟结果。此外,为进一步验证算法的适用性,模拟了溃坝算例。研究表明,改进的Quintic型核函数明显改善了粒子聚集现象,该SPH应力修正方法可以使液滴具有更均匀的粒子分布以及更光滑的自由表面,有效改善了SPH方法中的压应力不稳定作用以及自由表面流的模拟精度。

关键词： SPH 应力修正核函数液滴表面张力