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31.
新疆野生黑加仑与马林果实的营养成分分析 总被引:2,自引:0,他引:2
通过对新疆野生黑加仑和野生马林的脂肪油,8种微量元素,17种氨基酸以及维生素C的含量进行测定得出:黑加仑脂肪油含量为17.9%,马林的脂肪油含量为22.3%,其中,黑加仑脂肪油中,r-亚麻酸的含量为19.02%,而马林中,其含量为9.40%,黑加仑中K,Na,Ca,Cu,Zn,Fe的含量比马林中的含量高,而Mn,Mg元素的含量却比马林含量低;马林的维生素C含量为16.22mg/g,黑加仑的含量为108mg/g,黑加仑的氨基酸的总量为1.63%,马林为1.14%。 相似文献
32.
A planar map is a 2-cell embedding of a connected planar graph, loops and parallel edges allowed, on the sphere. A plane map is a planar map with a distinguished outside (“infinite”) face. An unrooted map is an equivalence class of maps under orientation-preserving homeomorphism, and a rooted map is a map with a distinguished oriented edge. Previously we obtained formulae for the number of unrooted planar n-edge maps of various classes, including all maps, non-separable maps, eulerian maps and loopless maps. In this article, using the same technique we obtain closed formulae for counting unrooted plane maps of all these classes and their duals. The corresponding formulae for rooted maps are known to be all sum-free; the formulae that we obtain for unrooted maps contain only a sum over the divisors of n. We count also unrooted two-vertex plane maps. 相似文献
33.
用三个关系式与Mathematica软件求第二类自然数幂和公式 总被引:1,自引:1,他引:0
首先介绍三个第二类自然数幂和关系式并对其中的两式给出证明,接着利用这些关系式与数学软件M athem atica4.0,给出求解第二类自然数幂和公式的若干机械计算方法. 相似文献
34.
关于矩阵和算子迹的一组不等式 总被引:1,自引:1,他引:0
周其生 《数学的实践与认识》2006,36(3):252-256
给出关于半正定矩阵迹和正算子迹的一组不等式,得到与邱贤忠关于实数的不等式的类似结果. 相似文献
35.
The classical Hardy theorem asserts that ■ and its Fourier transform ■ can not both be very rapidly decreasing.This theorem was generalized on Lie groups and also for the Fourier-Jacobi transform.However,on SU(1,1)there are infinitely many"good"functions in the sense that ■ and its spherical Fourier transform ■ both have good decay. In this paper,we shall characterize such functions on SU(1,1). 相似文献
36.
痕量铝在硝酸介质中能催化加速过氧化氢和高碘酸钾与二甲苯胺兰FF之间的褪色反应。研究了反应的最佳实验条件,建立了测定痕量铝的新方法。方法检出限为6.1×10-10gAl3+/mL,检测范围为0-1.0μgAl3+/25mL。本方法具有高灵敏度,选择性较好,操作简便,快速的特点。用以测定水样中的痕量铝,获得满意结果。 相似文献
37.
Masamichi Takase 《Topology》2004,43(6):1425-1447
Haefliger has shown that a smooth embedding of the (4k−1)-sphere in the 6k-sphere can be knotted in the smooth sense. In this paper, we give a formula with which we can detect the isotopy class of such a Haefliger knot. The formula is expressed in terms of the geometric characteristics of an extension, analogous to a Seifert surface, of the given embedding. In particular, the Hopf invariant associated to the extension plays a crucial role. This leads us to a new characterisation of Haefliger knots. 相似文献
38.
A rigorous and systematic intercomparison of codes used for the retrieval of trace gas profiles from high-resolution ground-based solar absorption FTIR measurements is presented for the first time. Spectra were analyzed with the two widely used independent, retrieval codes: SFIT2 and PROFFIT9. Vertical profiles of O3, HNO3, HDO, and N2O were derived from the same set of typical observed spectra. Analysis of O3 was improved by using updated line parameters. It is shown that profiles and total column amounts are in excellent agreement, when similar constraints are applied, and that the resolution kernel matrices are also consistent. Owing to the limited altitude resolution of ground-based observations, the impact of the constraints on the solution is not negligible. It is shown that the results are also compatible for independently chosen constraints. Perspectives for refined constraints are discussed. It can be concluded that the error budget introduced by the radiative transfer code and the retrieval algorithm on total columns deduced from high-resolution ground-based solar FTIR spectra is below 1%. 相似文献
39.
N. Segovia M. A. Armienta C. Valdes M. Mena J. L. Seidel M. Monnin P. Pea M. B. E. Lopez A. V. Reyes 《Radiation measurements》2003,36(1-6):379-383
Soil radon has been monitored at two fixed stations in the northern flank of Popocatepetl Volcano, a high risk volcano located 60 km SE from Mexico City. Water samples from three springs were also studied for radon as well as major and trace elements. Radon in the soil was recorded using track detectors. Radon in the water samples was evaluated using the liquid scintillation method and an Alphaguard. The major elements were determined through conventional chemical methods and trace elements using an ICP-MS equipment. Soil radon levels were low, indicating a moderate diffuse degassing through the flanks of the volcano. Groundwater radon had almost no relation with the eruptive stages. Water chemistry was stable in the reported time (2000–2002). 相似文献
40.
Young Ja Park 《Proceedings of the American Mathematical Society》2004,132(7):2075-2083
A logarithmic Sobolev trace inequality is derived. Bounds on the best constant for this inequality from above and below are investigated using the sharp Sobolev inequality and the sharp logarithmic Sobolev inequality.