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多种气相色谱联用技术分析陕西刺五加茎挥发油的化学成分 总被引:4,自引:0,他引:4
采用气相色谱/四极杆质谱(GC/qMS)、气相色谱/正交加速飞行时间质谱(GC/oaTOFMS)和气相色谱/傅里叶变换红外光谱(GC/FTIR)联用技术,对一种陕西产刺五加Acanthopanax senticosus (Rupr. et Maxim.) Harms茎挥发油的化学成分进行了分析。基于GC/qMS谱库的检索功能,结合GC/FTIR在结构鉴别上的优势和GC/oaTOFMS对质谱碎片离子精确的质量测定功能,成功地实现了对68个色谱组分的定性分析。与使用单一的联用技术(例如GC/qMS)相比,利用多种色谱联用技术在定性分析上的互补性,可以明显提高对组成复杂的挥发油类样品分析的可靠性。 相似文献
54.
微波消解-原子吸收法分析并比较四种贝母中的微量元素 总被引:6,自引:1,他引:6
利用火焰原子吸收分光光度法(FAAS)及石墨炉原子吸收分光光度法(GFAAS)测定了浙贝、象贝、东贝、川贝4种贝母中15种微量元素的含量。同时考察了不同微波消解条件对分析结果的影响, 确定了原子吸收分光光度法测定的最佳条件,并且以微量元素含量作为指标对其进行了主成分分析。实验结果表明, 微波消解法操作简便、快速、样品消解完全, 空白值低, 选择性好, 方法相对标准偏差小于3.96%,回收率在91.0%~108.7%。主成分分析法在反映不同样品微量元素含量的差异程度上具有应用价值。 相似文献
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Jing Deng Lifang Ye Guanghao Xu Zhiguo Ma Hui Cao Ying Zhang Menghua Wu 《Journal of separation science》2023,46(9):2300063
Artemisiae Argyi Folium (Aiye in Chinese) has been widely used since ancient times. In the Lingnan region (Southern China), the leaf of Artemisia verlotorum Lamotte, which is named Hongjiaoai (HJA) because the roots are red (Hongjiao means red foot in Chinese), has been used as a local substitute for Artemisiae Argyi Folium. The plant has a long medicinal and edible history that can be traced to the Jin Dynasty. However, there is no systematic and reliable method to control the quality of Artemisiae Verlotori Folium. In this study, a comprehensive method involving high-performance liquid chromatography coupled with diode array detection and quadrupole-time-of-flight high-definition mass spectrometry was established to identify and quantify eight constituents (including organic acids and flavonoids) in Artemisiae Verlotori Folium and Artemisiae Argyi Folium as well as high-performance liquid chromatography fingerprints of the two varieties. Moreover, dissimilarities of chemical compositions among the two varieties were further investigated by orthogonal partial least squares discrimination analysis and cluster analysis. This research not only explored the similarities and differences between Artemisiae Verlotori Folium and Artemisiae Argyi Folium in eight components but also provided a qualitative and quantitative analytical method that quickly, accurately, and comprehensively assesses the quality of Artemisiae Verlotori Folium. 相似文献
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应用均匀设计法对深山草莓花瓣诱导愈伤组织和愈伤组织再分化芽苗的主要因子和水平进行了探讨.结果表明,深山草莓花瓣愈伤组织诱导的适宜培养基为LS+TDZ 2.06 mg.L-1+2,4-D 0.60 mg.L-1,诱导率为98%;愈伤组织再分化芽苗的适宜培养基为1/2 LS+TDZ 2.30 mg.L-1+NAA 0.10 mg.L-1+KT1.30 mg.L-1,分化率为96.3%.炼苗移栽后观察植株的形态、花、果及生长等特征,以筛选具有优良性状的株系. 相似文献
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Henryk Petryk 《Comptes Rendus Mecanique》2003,331(7):469-474
The incremental energy minimization is examined as a method of determining solution paths for time-independent dissipative solids. Isothermal quasi-static deformations are considered, and the deformation work is locally decomposed into the increments in free energy and intrinsic dissipation. General conditions necessary for the applicability of the minimization procedure are derived and discussed. To cite this article: H. Petryk, C. R. Mecanique 331 (2003). 相似文献
59.
The seismic response of a set of ten non-equally spaced, non-equally sized, homogeneous blocks partially imbedded in a soft soil layer overlying a hard halfspace is studied numerically and shown to be generally larger, in terms of amplitude, duration and spatial variability than that of the ground in the presence of one block or in the absence of blocks. This is qualitatively similar to observed seismic response in the past at sites such as Mexico City and suggests that the built portion of cities may, under certain conditions, play a significant role in the global seismic response of a city. To cite this article: C. Tsogka, A. Wirgin, C. R. Mecanique 331 (2003). 相似文献
60.
A. Crumeyrolle 《Journal of Geometry and Physics》1985,2(3):107-134
Planck's constant is very useful in the development of the theory of symplectic Clifford algebras introduced by the author in 1977 [1,a], and to solve many connected problems for example the Poisson Lie algebra deformations [1,c]. In this paper we give a precise link between a complex structure J and the Fourier transform which is nothing but the natural left action of the covering J? of J in a symplectic convenient spinor space (modulo a constant factor).Thus Fourier transform becomes a geometric transformation separated from integration technics, good peculiarity for global problems. We explain nice algebraic properties of the Fourier transform taking them in the symplectic context with adapted metric in any signature. Some applications are given: Hermite's functions, Plancherel-Parseval's theorem, covariance problemes … . Our approach is particularly convenient for explain results in Maslov's theory [1,b] and the difficulties in defining a global Fourier transform over a symplectic manifold. 相似文献