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71.
Muhammad IMRAN Syed Ahtsham ul Haq BOKHARY Ali AHMAD Andrea SEMANIOV-FENOVíKOV 《数学物理学报(B辑英文版)》2013,33(1):187-206
In this paper,we are dealing with the study of the metric dimension of some classes of regular graphs by considering a class of bridgeless cubic graphs called the flower snarks Jn,a class of cubic convex polytopes considering the open problem raised in [M.Imran et al.,families of plane graphs with constant metric dimension,Utilitas Math.,in press] and finally Harary graphs H 5,n by partially answering to an open problem proposed in [I.Javaid et al.,Families of regular graphs with constant metric dimension,Utilitas Math.,2012,88:43-57].We prove that these classes of regular graphs have constant metric dimension. 相似文献
72.
The aim of this work is to study the main thermoluminescence (TL) characteristics of the inorganic polyminerals extracted from dehydrated Jamaica flower or roselle (Hibiscus sabdariffa L.) belonging to Malvaceae family of Mexican origin. TL emission properties of the polymineral fraction in powder were studied using the initial rise (IR) method. The complex structure and kinetic parameters of the glow curves have been analysed accurately using the computerized glow curve deconvolution (CGCD) assuming an exponential distribution of trapping levels. The extension of the IR method to the case of a continuous and exponential distribution of traps is reported, such as the derivation of the TL glow curve deconvolution functions for continuous trap distribution. CGCD is performed both in the case of frequency factor, s, temperature independent, and in the case with the s function of temperature. 相似文献
73.
Violeta?MadjarovaEmail author Satoru?Toyooka Hikaru?Nagasawa Hirofumi?Kadono 《Optical Review》2003,10(5):370-374
A dynamic electronic speckle pattern interferometry (ESPI) method was applied to study the blooming process in two kinds of flowers, the lily and the tulip. The complicated displacement fields of the flower petals were precisely monitored throughout the entire blooming process. The optical setup is a Fizeau type interferometer with relatively high robustness to air turbulence and vibrations. For quantitative evaluation of the displacement field, the subtraction-addition method (SAM), which utilizes only the digital signal processing of a sequence of images, was implemented. Measurements with accuracy in the range of λ/10 were achieved. 相似文献
74.
吉林省长白山野生百花中微量元素的分析 总被引:1,自引:0,他引:1
应用电感耦合等离子发射光谱仪(ICP-AES),首次对采自长白山野生百合花进行了微量元素成分分析,其结果为综合开发利用长白山野生百合花资源提供科学依据。 相似文献
75.
76.
Suppose that p = (p1, p2, …, pN) and q = (q1, q2, …, qN) are two configurations in
, which are centers of balls B
d
(p
i
, r
i
) and B
d
(q
i
, r
i
) of radius r
i
, for i = 1, …, N. In [9] it was conjectured that if the pairwise distances between ball centers p are contracted in going to the centers q,
then the volume of the union of the balls does not increase. For d = 2 this was proved in [1], and for the case when the centers are contracted continuously for all d in [2]. One extension
of the Kneser-Poulsen conjecture, suggested in [6], was to consider various Boolean expressions in the unions and intersections
of the balls, called flowers, where appropriate pairs of centers are only permitted to increase, and others are only permitted
to decrease. Again under these distance constraints, the volume of the flower was conjectured to change in a monotone way.
Here we show that these generalized Kneser-Poulsen flower conjectures are equivalent to an inequality between certain integrals
of functions (called flower weight functions) over
, where the functions in question are constructed from maximum and minimum operations applied to functions each being radially
symmetric monotone decreasing and integrable.
Research supported in part by NSF Grant No. DMS-0209595. 相似文献
77.
目的 探究金银花茶样品中8种微量元素的溶出特性。方法 基于电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP-MS),测定样品中Na、Ca、Mg、Mn、Fe、Zn、Cu、Se 8种微量元素含量,并分别研究了浸泡时间、浸泡次数及浸泡温度与元素溶出特性之间的关系。结果 结果表明,金银花茶中微量元素含量丰富,8种元素含量由高到低的顺序为:Ca>Mg> Fe>Na>Mn> Zn>Cu>Se。各元素溶出量随浸泡时间延长而升高,其中Fe溶出率最低,表明Fe最难溶出。除Na和Se以外,各元素溶出量随浸泡次数增加而降低,随浸泡温度升高而升高;Na的溶出量随浸泡次数增加呈先降低后升高的趋势,而Se的溶出量随浸泡次数增加而降低;Na和Se的溶出量均随浸泡温度升高呈先升高再降低的趋势。各元素溶出量与浸泡时间、浸泡次数及浸泡温度之间的关系均可通过建立不同类型的数学模型进行描述。结论 从保健茶饮的功能性和风味角度考虑,金银花茶冲泡应选用100℃的水温,且冲泡次数应不超过4次。 相似文献
78.
洋槐叶和槐花中营养成分分析的研究 总被引:5,自引:0,他引:5
用现代仪器分析方法对洋槐花和槐叶中蛋白质、还原糖、总糖、抗坏血酸、氨基态氮含量及微量元素含量进行了测试,并对其作为饲料的价值进行了分析。结果显示,洋槐花和槐叶作为饲料资源具有良好的应用前景。 相似文献
79.
Neha Pawar Shital Panchal Dhananjay Kawle Chhaya Gadgoli 《Natural product research》2019,33(6):884-888
Flowers of the plant Nyctanthes arbor-tristis (NAT) are widely used in the traditional medicinal systems of several Asian countries. In the present study, potential genotoxicity and modulatory effects of ethanolic extract of NAT flower calyx (NAT FCE) and crocin, a carotenoid principle were evaluated employing standard Salmonella assay. Experiments evaluating the genotoxic potential of NAT FCE and crocin, with and without the S9-activation in TA 98, TA 100 and TA 102 showed a lack of increase in revertant mutants. Evaluation of modulatory effects of NAT FCE and crocin, without the S9, showed significant decrease in the number of 4-nitro-o-phenylenediamine-, sodium azide- and ethyl methanesulfonate-induced revertants. However, with S9, NAT FCE and crocin moderately increased the 2-aminoanthracene-induced revertants in TA 98; they moderately decreased revertants in TA 100 and TA 102. Both NAT FCE and crocin have been shown to be non-genotoxic and to be able to modulate responses of standard mutagens. 相似文献
80.
洋槐花中微量元素的光谱测定 总被引:31,自引:2,他引:29
采用火焰原子吸收法同时测定了洋槐花中K,Na,Ca,Mg,Pb,Cd,Cu,Mn,Co,Zn,Cr,Fe等12种微量元素的含量。方法的相对标准偏差介于0.07%~2.31%, 回收率介于97.0%~107.0%。结果表明,洋槐花中含有丰富的微量元素,其含量K>Ca>Mg>Na>Fe>Zn>Cu>Mn>Co>Pb>Cr>Cd, 说明洋槐花具有较高的营养价值。 相似文献