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1.
Summary A high-performance liquid chromatographic method for the separation and determination of gastrodin,p-hydroxybenzyl alcohol, vanillyl alcohol,p-hydroxylbenzaldehyde and vanillin in extract of Chinese herbal medicine tall gastrodia tuber (Chinese name: Tianma) was established.
The chromatographic conditions were optimized by means of computer-assisted method development technique. Dry-Lab software
was used to model the retention behavior of the compounds as a function of gradient conditions, based on the data from two
scouting gradient runs. Under the optimized conditions: column, Kromasil-C18, 5 μm, 15×0.46-cm; solvent A, water; solvent
B, methanol; gradient, 5/44/65/65% B at 0/9/12/15 min; flow rate, 1.00 mL min−1; temperature, ambient, the quality of tall gastrodia tubers from different sources and tianma injection were examined. 相似文献
2.
Discriminant Analysis is used as a part of a research, which aims at using expired air analysis for the early location of entrapped people under the ruins of collapsed buildings in an earthquake. This work focuses on the possibility of distinguishing Volatile Organic Compounds (VOCs) in the entrapment area which originate from different sources. Five categories of samples were analyzed by Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC-MS). Expired air samples from healthy humans (Category 1) and fasting people (Category 2) were analyzed for studying the VOCs attributed to entrapped people. Headspace air of urban waste disposal bins (Category 3), headspace air of bags with decaying human bodies (Category 4) and urban air samples (Category 5) were analyzed for studying the VOCs attributed to background sources. Discriminant Rotation, a specific type of Discriminant Analysis was applied on the VOCs concentration matrix of the five categories. Combinations of VOCs that best discriminated each category were determined. Cluster Analysis was used to validate the results of Discriminant Analysis. The advantages and limitations of the method are presented and discussed. 相似文献
3.
Linus Kramer 《Geometriae Dedicata》2002,92(1):145-178
In these notes we describe some buildings related to complex Kac–Moody groups. First we describe the spherical building of SLn() (i.e. the projective geometry PG(n)) and its Veronese representation. Next we recall the construction of the affine building associated to a discrete valuation on the rational function field (z). Then we describe the same building in terms of complex Laurent polynomials, and introduce the Veronese representation, which is an equivariant embedding of the building into an affine Kac–Moody algebra. Next, we introduce topological twin buildings. These buildings can be used for a proof which is a variant of the proof by Quillen and Mitchell, of Bott periodicity which uses only topological geometry. At the end we indicate very briefly that the whole process works also for affine real almost split Kac–Moody groups.Supported by a Heisenberg fellowship by the Deutsche Forschungsgemeinschaft. 相似文献
4.
We construct a homological approximation to the partition complex,and identify it as the Tits building. This gives a homologicalrelationship between the symmetric group and the affine group,leads to a geometric tie between symmetric powers of spheresand the Steinberg idempotent, and allows us to use the self-dualityof the Steinberg module to study layers in the Goodwillie towerof the identity functor. 2000 Mathematics Subject Classification:55N25, 55S15, 20B30, 55P25. 相似文献
5.
Andreas Balser 《Geometriae Dedicata》2008,131(1):123-158
For a Euclidean building X of type A
2, we classify the 0-dimensional subbuildings A of ∂
T
X that occur as the asymptotic boundary of closed convex subsets. In particular, we show that triviality of the holonomy of
a triple (of points of A) is (essentially) sufficient. To prove this, we construct new convex subsets as the union of convex sets.
相似文献
6.
地方建筑作为一种文化遗产,具有较高的精神和经济价值以及深远的历史意义.当前,由于人们忽视地方建筑的价值,造成地方建筑资源的衰败.对如何正确保护地方建筑这一个重要课题进行了系统的总结和论述. 相似文献
7.
We prove the following rigidity results. Coarse equivalences between metrically complete Euclidean buildings preserve spherical buildings at infinity. If all irreducible factors have dimension at least two, then coarsely equivalent Euclidean buildings are isometric (up to scaling factors); if in addition none of the irreducible factors is a Euclidean cone, then the isometry is unique and has finite distance from the coarse equivalence. 相似文献
8.
Sur les immeubles triangulaires et leurs automorphismes 总被引:1,自引:0,他引:1
Résumé Les travaux de J. Tits ont conduit à la classification complète des immeubles euclidiens de dimension supérieure ou égale
à 3. L’ensemble de ces immeubles à isomorphisme près est dénombrable et paramétré par les corps locaux qui leur correspondent.
Dans cet article nous nous intéressons aux immeubles triangulaires, qui sont euclidiens de dimension 2 et pour lesquelles
une paramétrisation analogue est impossible. Nous construisons une lamination Λ sur un espace topologique localement compact
séparé, dont l’espace des feuilles est l’ensemble des immeubles triangulaires à isomorphisme près. On considère ainsi les
immeubles triangulaires comme points d’un espace dont Λ est une désingularisation naturelle. Nous établissons des résultats
de chirurgie sur les immeubles triangulaires à données locales fixées. Ils entra?nent par exemple que Λ est topologiquement
transitive. Nous montrons qu’un immeuble triangulaire générique au sens de Baire a un groupe d’automorphismes trivial et qu’il
contient toutes les géométries locales possibles. L’espace des immeubles triangulaires à isomorphisme près est un nouvel exemple
d’espace non commutatif.
Le second auteur a été en partie financé par JSPS. 相似文献
9.
本文以连杆节间为界,按弹性支座上和Timoshenko悬臂梁建立力墙部分的振动方程,按一般框架建立框架部分的振动方程,根据力,变形协调条件,形成底层大空间高层建筑结构的自由振动,并据此计算其自由振动。 相似文献
10.
针对四个处理机的Transputer并行计算机系统,建立了建筑风压数值模拟问题基于SIM-PLEC算法的几种并行化策略:分区并行策略、方程并行策略和双重并行策略。对各种策略的计算流程、数据通讯及并行效率等进行了分析和比较,并通过实例计算作了验证。 相似文献