西藏产雪莲花的化学成分研究

本学位论文报道了作为传统藏药材广泛使用的西藏产雪莲花化学成分的研究。论文由五章组成，第一章是三种西藏产雪莲花的化学成分的系统分离纯化和结构鉴定；第二章为西藏产雪莲花化学成分的液-质及串联质谱联用分析；第三章提出了以HPLC和TLC为检测方法的雪莲花药材质量标准草案；第四章给出了对西藏产雪莲花挥发油化学成分的气-质联用分析结果；第五章概述了雪莲花的化学成分及药理研究进展。 第一章包括三个部分。第一部分报道了绵头雪莲花(Saussurea laniceps Hand.-Mazz.)全草乙醇提取物化学成分的分离鉴定。采用正相硅胶柱层析及凝胶柱层析等分离方法，从西藏产绵头雪莲花的乙醇提取物中共分离鉴定出15个化合物。其中11个化合物为首次从该植物中分离得到，当中2个化合物系在凤毛菊属植物中首次发现。第二部分报道了水母雪莲花(Saussurea medusa Maxim.)全草乙醇提取物的化学成分。采用正、反相硅胶柱层析及凝胶柱层析等分离方法，共分离鉴定出15个化合物，其中1个为新化合物，另有4个化合物为首次从该植物中分离得到。新化合物结构通过质谱和一维及二维核磁共振等波谱解析方法及碱水解反应确定为巴豆酰基-高车前苷(M-7)。第三部分报道了三指雪莲花 (Saussurea tridactyla Sch.-Bip. ex Hook. f.)全草乙醇提取物的化学成分。采用正相硅胶柱层析及凝胶柱层析等分离方法，共分离鉴定出7个化合物，其中1个化合物为首次从该植物中分离得到。 第二章也包括三个部分。首先是采用液-质联用(HPLC-DAD-ESI-MSn)分析方法，对7个西藏不同产地的三指雪莲花化学成分进行了分析，通过与标准品的 UV和MS数据比较，共鉴定出14个峰，并对其中8个共有成分进行了定量测定。其次是关于八种西藏产雪莲花化学成分的液-质联用(HPLC-DAD-ESI-MSn)分析，通过与标准品的UV和MS数据比较，共鉴定出15个峰，并对其中8个共有成分进行了定量检测。最后通过对八种西藏产雪莲花主要化学成分的多级串联质谱(ESI-MSn)分析，快速、灵敏地鉴定出10个黄酮和3个香豆素化学成分。 第三章同样包括三个部分。首先是以绵头雪莲花中主要香豆素成分东莨菪素和伞形花内酯为对照品，通过TLC定性检测和HPLC含量测定，草拟出较严谨的药材质量标准。其次是将绵头雪莲花、三指雪莲花和雪兔子作为一个药材看待，草拟了以东莨菪素和伞形花内酯的TLC检测为指标的药材质量标准。最后是针对水母雪莲花，以主要黄酮成分芹菜素-7-O-b-D-葡萄糖苷为对照品作TLC检测，并草拟出该药材的质量标准草案。 第四章报道了西藏产雪莲花挥发油的化学成分分析。采用传统水蒸气蒸馏法分别从八种雪莲花全草中提取挥发油，利用气相色谱-质谱联用技术分别从水母雪莲花、绵头雪莲花、槲叶雪莲花、云状雪兔子、拉萨雪兔子、小果雪兔子、雪兔子和三指雪莲花中分别鉴定出83、83、56、34、21、20、24和20个化学成分，分别占其挥发油总量的70.7%、76.0%、82.2%、55.4%、49.7%、70.4 %、76.2%和 76.7%。 第五章为综述，总结和概括了雪莲花的化学和药理研究进展。 The dissertation reports the investigation of the chemical constituents of the genus Saussurea. Quite a lot of species in this genus are traditional Tibetan medicinal plants, and hence have been widely used in traditional Tibetan medicine. This dissertation consisted of five chapters. The first chapter is on the chemical constituents of three Saussurea plants. The second section is about the analysis of chemical constituents of Saussurea plants using HPLC-MS and ESI-MS/MS. In the third chapter, we proposed quality-control standards for the Genus Saussurea based on TLC (thin layer chromatography) and HPLC. The fourth chapter is about chemical compositions of the essential oil from the whole plant of Saussurea plants. The last chapter reviews the research progress of the Genus Saussurea. The first chapter consists of three parts. The first part is about chemical constituents of ethanol extracts from whole plant of Saussurea laniceps Hand.-Mazz. Fifteen compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. Among them, eleven compounds were isolated from this plant for the first time, and two compounds were isolated from Genus Saussurea for the first time. The second part is about chemical constituents of ethanol extracts from whole plant of Saussurea medusa Maxim. Fifteen compounds were isolated by column chromatography on normal phase, reversed phase silica gel and Sephadex LH-20. Five of them were isolated from this plant for the first time, and there is one new flavonoid glucoside which was identified as 6″-O-crotonoyl-homoplantaginin (M-7) based on the evidence of one- and two-dimensional nuclear magnetic resonance, mass spectrometry analysis, and alkaline hydrolysis reaction. The last part is about chemical constituents of ethanol extracts from whole plant of Saussurea tridactyla Sch.-Bip. ex Hook. f.. Seven compounds were isolated by column chromatography on normal phase silica gel and Sephadex LH-20. There is one compound which was isolated from this plant for the first time. The second chapter consists of three parts. In the first part, we analyzed the chemical constituents of S. tridactyla collected from seven different places in Tibet using HPLC-DAD-ESI-MSn. Fourteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds, among which eight common peaks were quantified. In the second part, we analyzed the chemical constituents of eight Saussurea species using HPLC-DAD-ESI-MSn method. Fifteen peaks in the HPLC were identified by comparison of UV and MS spectra with those of authentic compounds and eight main peaks of them were quantified. In the last part, we analyzed the chemical compounds of the above eight Saussurea plants directly by ESI-MS/MS. Thirteen major compounds, including 10 flavonoids and 3 coumarins were easily rapidly identified. The third chapter consists of three parts. In the first part, we proposed a comparative high quality-control standard for S. laniceps, based on quality detection by TLC and quantity analysis by HPLC using two major compounds (umbelliferone and scopoletin) as standard compounds. In the second part, in viewing S. laniceps, S. tridactyla and S. gossypiphora as the members of one family of medicinal herbs, we suggested a quality-control standard based on the TLC detection of the two major compounds (umbelliferone and scopoletin). In the last part, we proposed a quality-control standard for S. medusa based on the TLC detection of its major component (apigenin 7-O-glucoside). The four chapter analyzed the chemical constituents of essential oil of eight Saussurea species. The essential oils were extracted from the whole plants of these samples with water stream distillation. By GC-MS analysis, we identified eighty-three compounds from S. medusa, eighty-three from S. laniceps, fifty-six from S. quercifolia, thirty-four from S. aster, twenty-one from S. kingii, twenty from S. simpsoniana, twenty-four from S. gossypiphora, and twenty from S. tridactyla respetively, which accounted for 70.7%, 76.0%, 82.2%, 55.4%, 49.7%, 70.4 %, 76.2% and 76.7% of the total essential oil, respectively. The last chapter reviews the research progress of the Genus Saussurea.

Identification of a quasiparticle band in very neutron-rich Zr-104

The high spin levels of a very neutron-rich Zr-104 nucleus have been reinvestigated by measuring the prompt. rays in the spontaneous fission of Cf-252. The ground-state band has been confirmed. A new sideband has been identified with a band-head energy at 1928.7 keV. The projected shell model is employed to investigate the band structure of Zr-104. The results of calculated levels are in good agreement with the experimental data, and suggest that the new band in Zr-104 may be based on the neutron nu 5/2(-)[532] circle times nu 3/2(+)[411] configuration.

Azimuthal di-hadron correlations in d plus Au and Au plus Au collisions at root s(NN)=200 GeV measured at the STAR detector

Yields, correlation shapes, and mean transverse momenta p(T) of charged particles associated with intermediate-to high-p(T) trigger particles (2.5 < p(T) < 10 GeV/c) in d + Au and Au + Au collisions at root s(NN) = 200 GeV are presented. For associated particles at higher p(T) greater than or similar to 2.5 GeV/c, narrow correlation peaks are seen in d + Au and Au + Au, indicating that the main production mechanism is jet fragmentation. At lower associated particle pT < 2 GeV/c, a large enhancement of the near- (Delta phi similar to 0) and away-side (Delta phi similar to pi) associated yields is found, together with a strong broadening of the away-side azimuthal distributions in Au + Au collisions compared to d + Au measurements, suggesting that other particle production mechanisms play a role. This is further supported by the observed significant softening of the away-side associated particle yield distribution at Delta phi similar to pi in central Au + Au collisions.

Balance functions from Au+Au, d+Au, and p+p collisions at root s(NN)=200 GeV

Balance functions have been measured for charged-particle pairs, identified charged-pion pairs, and identified charged-kaon pairs in Au + Au, d + Au, and p + p collisions at root s(NN) = 200 GeV at the Relativistic Heavy Ion Collider using the STAR detector. These balance functions are presented in terms of relative pseudorapidity, Delta eta, relative rapidity, Delta y, relative azimuthal angle, Delta phi, and invariant relative momentum, q(inv). For charged-particle pairs, the width of the balance function in terms of Delta eta scales smoothly with the number of participating nucleons, while HIJING and UrQMD model calculations show no dependence on centrality or system size. For charged-particle and charged-pion pairs, the balance functions widths in terms of Delta eta and Delta y are narrower in central Au + Au collisions than in peripheral collisions. The width for central collisions is consistent with thermal blast-wave models where the balancing charges are highly correlated in coordinate space at breakup. This strong correlation might be explained by either delayed hadronization or limited diffusion during the reaction. Furthermore, the narrowing trend is consistent with the lower kinetic temperatures inherent to more central collisions. In contrast, the width of the balance function for charged-kaon pairs in terms of Delta y shows little centrality dependence, which may signal a different production mechanism for kaons. The widths of the balance functions for charged pions and kaons in terms of q(inv) narrow in central collisions compared to peripheral collisions, which may be driven by the change in the kinetic temperature.

Comparison of 6Mo/MCM-22 and 6Mo/ZSM-5 in the MDA process

A comparison of methane dehydroaromatization (MDA) on 6Mo/MCM-22 and 6Mo/ZSM-5 was carried out using a gas mixture of 90%CH4, 2%CO2 and 8%Ar as the feed. The results indicate that the stability of 6Mo/MCM-22 is better than that of 6Mo/ZSM-5. A detailed study reveals that the ability for coke accommodation and the retention of the shape selectivity for aromatics formation is responsible for the stability of a MDA catalyst.

Multi-walled carbon nanotubes supported Pt-Fe cathodic catalyst for direct methanol fuel cell

Multi-walled carbon nanotubes supported Pt-Fe cathodic catalyst shows higher specific activity towards oxygen reduction reaction as compared to Pt/MWNTs when employed as cathodic catalyst in direct methanol fuel cell.

黑土区县域生态工程建设对农业景观的调控

近年来,东北典型黑土区的水土流失问题得到了广泛的关注。该文运用景观生态学的空间分析方法,在地理信息系统GIS支持下,以1989年和2002年陆地资源卫星LandsatTM为主要信息源,结合测绘图件、统计数据及野外调查,分析黑土侵蚀区典型县域(拜泉县)生态恢复与重建的景观结构和水土保持效应。研究结果表明从1989到2002年,研究区耕地面积下降24731.01hm2,林草地面积增加了13567.53hm2,林网进一步完善,水库和塘坝数量由88座增加到1490座。全县55%的水蚀面积得到治理,82.2%的风蚀农田得到林网的防护,43.7%的景观地表超渗径流得到集蓄利用,大于1.5°坡耕地泥沙径流拦截面积增加1420.10hm2。大规模生态建设下,区域景观类型数量和空间配置发生了较大的变化,景观结构的调整对其水土保持功能起到了很好的调控作用。

侵蚀泥沙、有机质和全氮富集规律研究

在自然降雨下 ,研究降雨、坡度、耕作和施肥对侵蚀泥沙、有机质和全N富集率的影响 ,分析土壤和泥沙颗粒组成、富集与泥沙有机质和全N富集的关系 ,揭示土壤有机质和全N在泥沙中的富集规律 .结果表明 ,泥沙粘粒的富集导致有机质和全N的富集 ,泥沙粘粒、有机质和全N富集率分别平均为 1.77、2 .0 9和 1.61.土壤侵蚀模数与泥沙有机质和全N富集率呈显著的负相关关系 ,降雨、坡度、施肥和耕作措施对泥沙有机质富集作用的影响是通过减少土壤侵蚀模数来实现的 ,减少土壤侵蚀的措施可增加泥沙有机质和全N的富集 .

松果采摘对长白山自然保护区红松天然更新的影响

在野外调查研究基础上 ,结合 2 0世纪 70年代未受干扰的红松天然林地面红松种子贮藏情况 ,分析了长白山自然保护区松果采摘后 ,红松林地面红松种源贮藏和分布变化 ,根据红松更新过程与动物的关系 ,探讨了松果采摘对红松更新条件的影响 .结果表明 ,松果采摘后 ,地面红松种子主要分布在地被物下层且大多呈单粒状分布 ,其贮藏量 1 5 82～ 2 6 4 0粒·hm-2 ,仅为 2 0世纪 70年代的 0 3%～ 0 5 % ,废种子比率 6 7 8%～ 86 2 % ,单粒状占总簇数的 4 6 8%～ 77 1 % ,对红松天然更新起重要作用的动物已减少或消失 ,表明松果采摘是长白山自然保护区红松天然更新的最大障碍之一 .

土壤中硝化抑制剂DMPP含量的气相色谱测定法

建立了一种检测土壤中吡唑类硝化抑制剂DMPP含量的气相色谱法。DMPP在NaOH溶液中可定量转化为DMP,从5种有机溶剂中选择氯仿作为DMP的萃取剂。本文采用吡啶做为内标物,内标校正因子fDMP和fDMPP分别为1.6775和3.3884。通过DB-1701气相色谱柱,氢火焰离子化检测器(FID)定量检测氯仿溶液萃取相中的DMP。本法添加回收率为97.4%～98.8%;RSD为0.70%～2.09%;土壤中DMPP的检出限为0.4mgkg-1。应用本法测定在潮棕壤中10℃、20℃和30℃时DMPP的降解半衰期分别为大于28d、14d和7d。

基于历史文献重建的近2000年中国温度变化比较研究

文中对不同学者利用不同来源中国历史文献资料重建的温度变化代用序列进行了比对,分析了同一地区不同序列之间及不同地区间序列的异同,以及造成这些异同的主要原因。结果表明:(1)不同学者重建的同一地区温度(或冷暖)变化序列具有较高的相似性;不同学者所估计的30a平均温度相对变幅完全一致(即在99.9%置信水平下,二者通过无显著性差别的检验)的时段平均占所有时段的73.4%,还有8.6%的时段虽在幅度大小上有差异但冷暖定性一致,二者共计占82%。(2)不同地区间的温度变化序列也具有较高的相关性,且重建区域相距越近其

Element enrichment and U-series isotopic characteristics of the hydrothermal sulfides at Jade site in the Okinawa Trough

The geochemical and U-series isotopic characteristics of hydrothermal sulfide samples from the Jade site (127A degrees 04.5'E, 27A degrees 15'N, water depth 1300-1450 m) at Jade site in the Okinawa Trough were analyzed. In the hydrothermal sulfide samples bearing sulfate (samples HOK1 and HOK2), the LREEs are relatively enriched. All the hydrothermal sulfide samples except HOK1 belong to Zn-rich hydrothermal sulfide. In comparison with Zn-rich hydrothermal sulfides from other fields, the contents of Zn, Pb, Ag, Cd, Au and Hg are higher, the contents of Fe, Al, Cr, Co, Ni, Sr, Te, Cs, Ti and U lower, and the Pb-210 radioactivity ratios and Pb-210/Pb ratios very low. In the hydrothermal sulfide mainly composed of sphalerite, the correlations between rare elements Hf and U, and Hf and Mn as well as that between dispersive elements Ga and Zn, are strongly positive; also the contents of Au and Ag are related to Fe-sulfide, because the low temperature promotes enrichment of Au and Ag. Meanwhile, the positive correlations between Fe and Bi and between Zn and Cd are not affected by the change of mineral assemblage. Based on the Pb-210/Pb ratios of hydrothermal sulfide samples (3.99x10(-5)-5.42x10(-5)), their U isotopic composition (U-238 content 1.15-2.53 ppm, U-238 activity 1.07-1.87 dpm/g, U-234 activity 1.15-2.09 dpm/g and U-234/U-238 ratio 1.07-1.14) and their Th-232 and Th-230 contents are at base level, and the chronological age of hydrothermal sulfide at Jade site in the Okinawa Trough is between 200 and 2000 yr.

海上低空大气波导的遥感反演及数值模拟研究

由于电磁波传播技术的广泛应用，大气环境成为电磁波传播研究的一个重要领域，尤其是天气变化多端的对流层。对流层大气波导是对流层大气的一种异常结构。大气波导可以使通信电路的相互干扰问题变得复杂，既可能干扰其他系统,又可能形成另外的系统，可以使探测系统产生超视距探测、雷达盲区等反常传播问题。然而通信系统或雷达探测系统遭受大气波导影响的时机具有很大的偶然性，它完全取决于对流层大气的特点。假如能够掌握大气波导的变化规律，准确而及时地预测、预报其出现的时间和地域，结合频率、射线波束、天线仰角和发生功率的选择，就能更好地发挥探测及通信设备的作用。因此，根据实际大气环境，分析、预测和预报大气波导，对于评估大气环境对电磁波传播和探测系统性能具有重要的理论意义和实际价值，尤其是在军事领域。然而在海洋大气环境中，特别是在广阔的海洋上，传统的海洋测量手段，如浮标、船只，获取的海洋水文数据稀少，探空数据更少，无法满足现代海洋大气环境监测所需的大范围观测信息，即使获取数据也很难保证数据点时间和空间的有效性；同时海洋大气边界层日变化缓慢，发生的大气波导持续时间长，比较稳定，对于海上舰船通讯等急需开展大气波导环境区域研究。我国是海洋大国，海岸线狭长，更需要开展沿海区域及近海对流层大气波导研究，特别是边界层内低空大气波导环境预测、预报研究。 目前国内大气波导的研究大多数情况下只注重单站波导发生情况，其代表的时空有效性是有限的，而在实际应用中，人们更加关注波导存在区域，因为波导区域决定了电磁波传输范围。本文针对我国近海区域大气波导不同的形成机理和类型，分别进行了研究。对于蒸发波导，本文利用卫星遥感获取海水表面温度、海面风场、气温、相对湿度等资料，建立卫星遥感资料与蒸发波导高度之间的诊断模式，研究大气波导反演算法和预测模型，首次分析了蒸发波导高度的空间不均匀性。对于低空表面波导和悬空波导，利用中尺度数值模式MM5对大气波导进行了系统的研究，填补了国内中尺度大气波导数值模拟研究的空白，同时选取典型的天气过程，进行了中尺度数值模拟个例研究，分析了大气波导形成机理。 本文主要工作如下： 一、结合P-J模式，利用AMSR-E卫星数据用两种神经网络方法反演了热带海域的蒸发波导高度，并进行了比较，两种方法得到的与浮标实测参数计算得到的蒸发波导高度之间的相关系数相当，都为0.82左右，均方根差后者比前者小，分别为2.64米和1.89米。神经网络直接反演蒸发波导高度方法要优于间接反演蒸发波导高度的方法。利用AMSR-E卫星数据直接反演了南海海域的蒸发波导高度，可以清楚看出蒸发波导高度的空间分布的不均匀性，为研究蒸发波导的环境特性奠定基础。 二、以2005年6月2日出现在黄海海域的大气波导为例，设计了三种数值试验，利用MM5模式对大气波导进行了24h数值模拟研究，包括是否加入常规探空资料进行格点分析同化，垂直分层的多寡，粗、细网格模拟比较分析。通过研究得到了以下结论：（1）利用常规资料进行格点同化对海上大气波导影响较小，对陆地影响较大；（2）垂直分层对大气波导特征参数影响明显，层数较多描述大气波导比较合适；（3）对于海上大气波导，细网格刻画大气波导特征参数比较细致，但粗网格的模拟已经足够进行大气波导分析。 三、以NCEP再分析资料为背景场,利用MM5模式，对2005年6月2日至4日出现在黄海海域的大气波导和2008年5月10日12时到11日12时由‘威玛逊’台风引起的大气波导分别进行了数值模拟研究。通过研究发现：模拟的修正折射率廓线与探空数据得到的廓线基本吻合，但是模拟的较强波导强度和高度普遍比实测的要小得多；同时给出了大气波导参数的演变过程，分析了两次大气波导形成的天气过程，说明了模拟的大气波导区域是可靠的和可信的； MM5模式能够模拟出特定天气条件下低空较强大气波导三维空间变化过程，可以为定量地描述大气波导特征提供理论和试验依据。