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A new triterpenoid from Kadsura coccinea

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Chinese Chemical Letters 2010年第11期21卷 1352-1354页

作者： Yan Song Qing Jie Zhao Yong sheng Jin Chuan Wei Feng hai sheng chen Department of Phytochemistry School of Pharmacy Second Military Medical University Shanghai 200433 China Department of Organic Chemistry School of Pharmacy Second Military Medical University Shanghai 200433 China

A new triterpenoid,possessing a lanost-9（11）-3-one skeleton,was isolated from the roots of Kadsura coccinea,based on the spectral analysis,its structure was elucidated as 3-hydroxy-12-acetoxycoccinic acid.

关键词： Kadsura coccinea Triterpene Coccinic acid

Fatigue-creep interaction based on continuum damage mechanics for AISI H13 hot work tool steel at elevated temperatures

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Journal of Iron and Steel Research International 2018年第5期25卷 580-588页

作者： hai-sheng chen Yong-qin Wang Wei-qi Du Liang Wu Yuan-xin LUO College of Mechanical Engineering Chongqing UniversityChongqing 400044 China State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China Chongqing Research Institute of China Coal Technology and Engineering Group Corp Chongqing 400016 China

AISI H13 （4Cr5MoSiV1） is one of the commonly used materials for extrusion tool, and it suffers from fatigue-creep damage during the hot extrusion process. Stress-controlled fatigue and creep-fatigue interaction tests were carried out at 500℃ to investigate its damage evolution. The accumulated plastic strain was selected to define the damage variable due to its clear physical meaning. A new fatigue-creep interaction damage model was proposed on the basis of continuum damage mechanics. A new equivalent impulse density for fatigue-creep tests was proposed to incorporate the holding time effect by transforming creep impulse density into fatigue impulse density. The experimental results indicated that the damage model is able to describe the damage evolution under these working conditions.

关键词： AISI H13 hot work tool steel · Fatigue-creep · Damage evolution ·Continuum damage mechanics ·Nonlinear interaction · Damage exponent

New flavone and isoflavone glycoside from Belamcanda chinensis

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Chinese Chemical Letters 2007年第2期18卷 158-160页

作者： Li Jin hai sheng chen Zhao Bao Xiang Shuang Liang Yong sheng Jin Jian Guo Liu College of Pharmacy Second Military Medical UniversityShanghai 200433China College of Bio-information Chongqing University of Posts and TelecommunicationsChongqing 400065China

The new flavone, 5,4′-dihydroxy-6,7-methylenedioxy-3′-methoxyflavone, and one new isoflavone glycoside, 3′,5′-dimethoxy irisolone-4′-O-β-d-glucoside were isolated from the rhizomes of Belamcanda chinensis. Their... 详细信息

关键词： Belamcanda chinensis Flavone Isoflavone glycoside

A New Bibenzyl Derivative from Bletilla striata

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Chinese Chemical Letters 2002年第3期13卷 231-232页

作者： Guang Xuan HAN Li Xin WANG Zheng Bing GU Wei Dong ZHANG hai sheng chen College of Pharmacy Second Military Medical UniversityShanghai 200433

A new compound was isolated from Bletilla striata. Its structure was elucidated as 5-hydroxy-4-(p-hydroxybenzyl)-3, 3-dimethoxybibenzyl by spectroscopic method.

关键词： Bletilla striata 5-hydroxy-4-(p-hydroxybenzyl)-3, 3-dimethoxybibenzyl.

Alkaloids from stems of Ervatamia yunnanensis

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Chinese Chemical Letters 2007年第6期18卷 697-699页

作者： Xin Gen Luo hai sheng chen Shuang Liang Mao Huang Wei Dong Xuan Li Jin College of Pharmacy Second Military Medical University Shanghai 200433 China Department of Pharmacy Guangzhou Military General Hospital Guangzhou 510010 China Center of New Drug Evaluation Institute of Basic Medical Sciences Second Military Medical University Shanghai 200433 China

Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, yunnanensine (I) is new. The other five are known alkaloids, namely: 19,20-E-vallesamine (II), 19s-heyneanine (III), ibogaine (IV... 详细信息

关键词： Ervatamia yunnanensis Indole alkaloids

Alkaloids from Stems of Ervatamia yunnanensis （Ⅱ）

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Chinese Chemical Letters 2006年第6期17卷 783-786页

作者： Shuang LIANG Xin Gen LUO hai sheng chen Xiao Dong ZHANG Mao HUANG Wen Yong LIU College of Pharmacy Second Military Medical University Shanghai 200433 Deoartment of Pharmacy Guangzhou Military General Hospital Guangzhou 510010 Center of New Drug Evaluation Institute of Basic Medical Sciences Second Military Medical University Shanghai 200433

Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, 10-hydroxy-19, 20-dihydroisositsirikine （I） is new. The other five are known alkaloids, namely： matrine （Ⅱ）, 19, 20-dihydroisositsirikine （Ⅲ）, 19-s-voacangarine （Ⅳ）, 1 l＇-methoxyl-19s- heyneanine （Ⅴ）, conodurine （Ⅵ）. The structural elucidation of the alkaloids was based on spectral means.

关键词： Ervatamia yunnanensis indole alkaloids.

Two new diterpenoids from Rabdosia japonica var. glaucocalyx

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Chinese Chemical Letters 2008年第7期19卷 852-854页

作者： Zhao Bao Xiang Yi Xin Xu Yang Shen Li Jin Hou Peng Wang hai sheng chen College of Pharmacy Second Military Medical University Shanghai 200433 China College of Bio-information Chongqing University of Posts and Telecommunications Chongqing 400065 China

Two new diterpenoids, named glaucocalyxin F and glaucocalyxin X, respectively, were isolated from the whole plant of Rabdosia japonica （Burm. f.） Hara var. glaucocalyx （Maxim.） Hara. Their structures was establish... 详细信息

关键词： Rabdosia japonica var. glaucocalyx Diterpenoid Glaucocalyxin F Glaucocalyxin X

压缩空气储能系统用多级离心压缩机进口导叶调节策略研究

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风机技术 2024年第2期66卷 24-30页

作者：王凯轩左志涛梁奇郭文宾陈吉祥陈海生中国科学院工程热物理研究所中国科学院大学毕节高新技术产业开发区国家能源大规模物理储能技术研发中心

压缩空气储能系统在储能过程中,储气装置内部压力不断升高,这要求压缩机在较大压比范围内工作。高效变工况是压缩空气储能系统中压缩机的核心要求,为实现这个设计目标需要采取合适的调节方式及其调节策略。可调进口导叶结构简单,可在工... 详细信息

压缩空气储能系统在储能过程中,储气装置内部压力不断升高,这要求压缩机在较大压比范围内工作。高效变工况是压缩空气储能系统中压缩机的核心要求,为实现这个设计目标需要采取合适的调节方式及其调节策略。可调进口导叶结构简单,可在工作过程中运行,并可利用伺服装置实现自动化,是目前压缩空气储能系统中压缩机最适合的调节方法之一。本文以压缩空气储能系统中某4级离心压缩机为研究对象,建立了一种适用于多级离心压缩机变工况调节的性能预测方法,采用数值模拟得出单级离心压缩机性能曲线,并编写级性能叠加程序获得整机性能曲线。利用最小二乘法将多级离心压缩机性能数据拟合为多项式函数,采用遗传算法建立了以等熵效率为优化目标,进口导叶开度为优化变量,整机出口压力或者流量为约束条件的可调进口导叶调节策略程序。

关键词：进口导叶调节多级离心压缩机调节策略

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超声速气流中激波对气膜冷却流动的干涉特性研究

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风机技术 2024年第3期66卷 17-24,46页

作者：高阿飞张华良尹钊徐玉杰陈海生中科南京未来能源系统研究院中国科学院工程热物理研究所中国科学院大学

激波会影响气膜冷却流场的流动特征,引起流场结构和冷却效率的变化。为探究激波干涉对气膜冷却的影响,本文采用数值模拟的方法对不同射流角度和不同吹风比工况下的超声速平板气膜冷却开展研究。结果表明:气膜冷却效率随吹风比的增大呈... 详细信息

激波会影响气膜冷却流场的流动特征,引起流场结构和冷却效率的变化。为探究激波干涉对气膜冷却的影响,本文采用数值模拟的方法对不同射流角度和不同吹风比工况下的超声速平板气膜冷却开展研究。结果表明:气膜冷却效率随吹风比的增大呈现先增大后减小的趋势,随着射流角度的增大,气膜在孔附近的展向覆盖效果逐渐提高,但冷却效率沿流向衰减加快;采用无量纲坐标系分析激波干涉对气膜流动的影响,获得激波与气膜冷却流动干涉在不同工况下对冷却效率的一致性影响规律,激波会造成冷却效率的明显降低;激波干涉下冷气容易产生三维流动分离,随着射流角度的增大,分离区极限流线的拓扑结构更加复杂。进一步引入均匀性指标参数分析激波干涉对气膜冷却效率的影响,不同射流角度下,激波干涉区域气膜冷却效率的均匀性随吹风比的增加呈先增大后减小的趋势。

关键词：超声速平板气膜冷却激波干涉气膜冷却效率