6 resultados para PAR-1

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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本论文以长白山阔叶红松林为研究对象,观测了阔叶红松林主要树种的光合生理生态特征,建立了单叶化汁卜片的光合作用模型,上推出群落的生产力模型,采用基于干物质生产过程的模型Sim-CYCLE,模型了该生态系统对·气候变化的响应。得到主要结论如下:(1)、在不同的CO2浓度和光合有效辐射条件下,长白山阔价卜红松林主要树种净光合速率月动态规律不同;气孔导度随着瞬时光合有效辐射强度和C02浓度的增加而有下降趋势。(2)、建立的适用于阔价f一红松林的单叶化气孔导度对环境因子气温(Ta)、光合有效辐射(PAR)、饱和水汽压(VPD)的响应模型:gs=PAR(-1.606Ta2+118.192Ta+1878.67)/(355.700+PAR)(-430.433+VPL),这是一个基于叶片光合机理的群落生产力模型,在模拟了长白山阔叶红松林群落生产力时取得了满意的效果。(3)、采用干物质产量理论的Sim-CYCLE模型,通过样地尺度的参数化模拟表明,长白山阔叶红松林生态系统的总初级生产力(GPP)为14.89Mgcha-1、净初级生产力(NPP)为8.22MgCha-1、净生态系统生产力困EP)为2.67MgCha-1;在CO2倍增和温度上升时碳积累在增加,净初级生产力(NPP)为9.03±1.51MgCha-1、净生态系统生产力(NEP)为2.95±0.47MgCha-1。

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本论文由三部分共4 章组成。第一部分阐述了大戟科大戟属传统中药千金子(Euphorbia lathyris L.)化学成分、生物学活性以及千金子化学成分的HPLC、UPLC-MS、GC-MS 分析成果。第二部分介绍了民族药材暖地大叶藓(Rhodobryum giganteum (Schwaegr.) Par.)的化学成分研究和结构鉴定。第三部分概述了大戟属 植物中大环二萜酯的研究进展。 第一章包括1-3 节。在第1, 2 节中报道了千金子(Euphorbia lathyris L.)95% 乙醇提取物的化学成分分离鉴定。我们采用正、反相硅胶柱层析、重结晶等各种分离方法,凭借MS、IR、NMR、X-ray 等现代仪器手段,从中共分离鉴定22 个化合物。其中8 个是高活性化合物前体-续随子烷型大环二萜及3 个巨大戟烷型二萜,还有香豆素、生物碱、甾体等类型,其中完成对5 个大环二萜酯构型的确认,对2 个二萜酯构型进行了修正。第3 节中介绍对千金子化学成分的细胞毒性、α-葡萄糖苷酶抑制活性、P-gp 表达抑制活性的模型筛选结果。 第二章包括3 节,第1 节报道不同产地千金子高效液相色谱定量分析结果。第2 节介绍了各大环二萜酯的HPLC-MS/MS 的分析结果,并且对其质谱裂解规律、UPLC-MS 快速鉴定方法做了进一步讨论。第3 节介绍了千金子挥发油成分分析。采用传统水蒸气蒸馏方法提取千金子中的挥发油,并经气相色谱-质谱联用(GC-MS)技术共分离鉴定出 49 个化合物,占挥发油总量的90.48%。 第三章包括1, 2 两节,第1 节报道了暖地大叶藓化学成分。采用正、反相硅胶,凝胶柱层析等各种分离方法和MS、IR、NMR 等解析手段,共分离鉴定10个化合物,其中一个环肽化合物为新化合物。第2 节介绍了暖地大叶藓挥发油成分分析,共分离鉴定出 52 个化合物,占其挥发油总量的85.67%。 第四章概述了大戟科大戟属植物中大环二萜酯的研究进展。 This dissertation consists of three parts. In the first part, it is elaborated that the phytochemical investigation from the traditional Chinese medicine: seeds of Euphorbia lathyris L.. Biological activity and constituents analysis by HPLC、UPLC-MS、GC-MS were reported. In the second part, it is discussed that the chemical constituents were isolated and identificated from minority nationalitical herb-Rhodobryum giganteum (Schwaegr.) Par.. The third part is a review about the progress of studies on macrocyclic diterpenes from Euphorbia. The first part is composed of 1-3 sections. The section 1and 2 is focused on the isolation and identification of chemical constituents from seeds of E. lathyris. 22 compounds were isolated from the seeds of E. lathyris. by isolation methods of column chromatography (silica gel, including reversed phase) and recrystallisation on the basis of spectroscopic methods including IR, MS, NMR and X-ray. In 8 macrocyclic and 3 ingenane diterpenes, the relative configuration of 5 macrocyclic diterpenes were confirmed, in which 2 were amended. In the third section, cell cytotoxic activity, restraining activity of α-Glucosidase and multidrug resistance (MDR) reversing activity about P-gp were tested. 5 potential revsering reagents were found. The second part is composed of 1-3 sections. In first section it is described that the quality of the chemical constituents of E. lathyris from 5 sources , which were analyzed by high-performance liquid chromatography. In addition, the fractionation rules of some macrocyclic diterpenes were discussed and Ultra Performance Liquid Chromatography/ electrospray ionization mass spectrometry (UPLC-MS) was applied for quick determination of compounds in the second section. In the third section, chemical analysis of the essential oil from seeds of E. lathyris by GC-MS were reported. The essential oil from the seeds of E. lathyris L. in Sichuan was extracted by steam distillation and 49 compounds were isolated and identified from the essential oil by gas chromatography-mass spectrometer (GC-MS). These compounds are accounted for 90.46% of the total essential oil. The second part, including section 4 and 5, is about the phytochemical investigation of R. giganteum. In the former section, ten compounds were isolated and identified. Among them, a new peptide was characterized by spectroscopic analysis including IR, MS and NMR. In the other section, 52 compounds were isolated and identified from the essential oil by gas chromatography-mass spectrometer (GC-MS). These compounds are accounted for 85.67% of the total essential oil. The third part is a review about the progress of studies on macrocyclic diterpenes from Euphorbia.

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鼎湖山通量站是中国通量网络(ChinaFLUX)中4个森林站之一,采用开路涡度相关方法,对南亚热带常绿针阔叶混交林进行生态系统尺度的CO2通量长期定位观测.利用2003,2004年2整年观测资料,分析该生态系统CO2通量时间变化特征及其受环境因子的制约关系.通过坐标转换、WPL订正和质量控制后,发现本通量站存在明显的夜间泄漏问题,因此采用Michaelis-Menten模型,利用白天(PAR>1.0μmol-1Photons·m-2·s-1)湍流充分条件-F(u*>0.2m·s-1)的通量资料,逐月拟合净

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算法被誉为计算的“灵魂”(spirit of computing),算法程序的可靠性和正确性对软件系统的可信度起着至关重要的作用。动态规划、贪心、分支限界等传统的算法设计策略缺乏有效的选择标准,一些算法形式化开发方法和工具的应用水平和范围也很有限,因此算法的可靠性已成为高可信软件系统的一个主要瓶颈。 作为军事运筹学的一个重要分支,装备保障计算主要研究军事活动中装备领域的决策优化问题,保障计算软件特别是算法的可靠性在很大程度上决定了装备保障的效率乃至军事行动的成败。利用形式化软件工程的研究成果、特别是引入算法程序的形式化开发方法,对我军通用装备保障领域中的大量算法类问题进行有效求解,有利于优化保障结构、统筹保障资源、整合保障力量、提高保障时效,促进装备整体战斗力水平的提升。 本文以高可信软件开发方法PAR为基础,面向装备保障计算的领域需求,提出了一类离散最优化问题(discrete optimization problem, DOP)的结构模型和算法推演技术,并成功推演了一系列典型的装备保障算法。本论文的主要创新性贡献如下: (1)定义了DOP的结构模型,提出了基于单点结构(Singleton)的问题分划递推策略,进而通过PAR算法推演生成问题的高效求解算法,涵盖了多种传统算法设计策略,显著提高了算法程序设计的机械化水平。 (2)提出了描述DOP分划递推过程的问题简约图(problem reduction graph, PRG)模型,并针对典型DOP结构推演得到了一组PRG构造算法模式,其中每个算法模式都涵盖了满足特定代数结构性质的一大类具体问题。 (3)阐述了PAR算法推演的范畴模型,为算法设计和重用提供了抽象而有效的方法指导。 (4)对我军通用装备保障领域具有代表性的48个问题进行了形式化的算法推演,构建了领域算法库。 (5)在PAR平台的基础上设计了装备保障算法开发平台的原型COPALM,支持DOP算法推演和重用,进而提高了相关应用软件的开发效率。

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0-1背包问题是经典的组合优化问题与NP完全问题,具有重要的应用价值与理论意义.本文使用PAR(Partition and Recurrence)方法形式化推导了0-1背包问题的高效动态规划算法程序.通过类比分析,该问题的若干变形问题的算法也可推导得到,算法通过PAR平台的自动生成系统转换成可执行语言程序并运行通过,保证了该类0-1背包问题算法的正确性和可靠性.本文主要的贡献是将PAR方法推广到能处理带约束条件的组合优化类问题,大大扩展了PAR方法的应用范围,为形式化开发高效高可信组合优化类算法开辟了一条新途径.

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A monolayer of 1:12 phosphomolybdic anion (PMo_(12)) was modified electrochemically on a glassy carbon electrode and its electrochemical behavior was studied with cyclic voltammetry (CV). It is shown that PMo_(12) film is adsoibed strongly on the surface of glassy carbon electrodes, H~+ ions in the solution plays an important role in the electrochemical processes of PMo_(12) film modified electrodes, whereas other anions, such as Cl~-, NO_3~-, SO_4~(2-), ClO_4~- and PO_4~(3-) etc., do not take par...