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101.
基于重氮反应测定亚硝酸根的研究—2.5次微分电分析法测定 NO_2~- 总被引:1,自引:1,他引:1
本文研究了在微酸性介质中,磺胺或对氨基苯乙酮与NO_2~-离子重氮化反应的实验条件。建立了一个灵敏、快速测定NO_2~-的分析方法,大量NO_3~-存在不干扰测定。 相似文献
102.
103.
A novel method for detecting and counting overlapping tracks in SSNTD by image processing techniques
Overlapping object detection and counting is a challenge in image processing. A new method for detecting and counting overlapping circles is presented in this paper. This method is based on pattern recognition and feature extraction using “neighborhood values“ in an object image by implementation of image processing techniques. The junction points are detected by assignment of a value for each pixel in an image. As is shown, the neighborhood values for junction points are larger than the values for other points. This distinction of neighborhood values is the main feature which can be utilized to identify the junction points and to count the overlapping tracks. This method can be used for recognizing and counting charged particle tracks, blood cells and also cancer cells. The method is called “Track Counting based on Neighborhood Values” and is symbolized by “TCNV”. 相似文献
104.
Gül Kaleli-Yılmaz Alper Hanci 《International Journal of Mathematical Education in Science & Technology》2016,47(5):674-695
The aim of this study is to determine how the TIMSS mathematics success of the 8th grade students differentiates according to the school type, gender, mathematics report mark, parents' education level, cognitive domains and cognitive domains by gender. Relational survey method was used in the study. Six-hundred fifty two 8th grade students studying in the same city in Turkey participated in this study. In this study, a 45 question test that was made up by choosing TIMSS 2011 mathematics questionnaire was used as a data collection tool. Quantitative data analysis methods were used in the data analysis, frequency, percentage, average, standard deviation, independent sample test, one-way analysis of variance and post-hoc tests were applied to data by using SPSS packaged software. At the end of the study, it was determined that the school type, mathematics school mark, parents' education level and cognitive domains influenced the students' TIMSS mathematics success but their gender was a neutral element. Moreover, it was seen that schools which are really successful in national exams are more successful in TIMSS exam; students whose mathematics school marks are 5 and whose parents graduated from university are more successful in TIMSS exams than others. 相似文献
105.
Ferenc Móricz 《Acta Mathematica Hungarica》2008,120(4):355-366
We introduce the higher order Lipschitz classes Λ
r
(α) and λ
r
(α) of periodic functions by means of the rth order difference operator, where r = 1, 2, ..., and 0 < α ≦ r. We study the smoothness property of a function f with absolutely convergent Fourier series and give best possible sufficient conditions in terms of its Fourier coefficients
in order that f belongs to one of the above classes.
This research was supported by the Hungarian National Foundation for Scientific Research under Grant T 046 192. 相似文献
106.
Petr Křenek 《Plasma Chemistry and Plasma Processing》2008,28(1):107-122
The article presents the calculation of thermophysical properties of the mixture water steam–argon which has been used to
further enhance the characteristics of plasma torches stabilized by the water wortex. The calculations were performed at the
temperatures 400–50,000 K and at 0.1 MPa. First, the composition and thermodynamic properties are determined by classical
methods. Further the calculations of viscosity, electrical conductivity and thermal conductivity of the mixture are computed
in the 4th approximation of the Chapman–Enskog method. The computation of collision integrals is described with special respect
to the interactions of charged particles where the necessary calculations for the Coulomb potential screened at the Debye
length were enlarged to cover the 4th approximation. Then the formulae describing the method based on the variational principle
of solving the system of Boltzmann integrodifferential equations are shortly introduced and the transport coefficients are
presented. 相似文献
107.
Luis Manuel Ribeiro Saraiva 《Historia Mathematica》2008,35(4):302-326
From the end of the 18th century until the appearance of the first issue of the Jornal de Sciencias Mathematicas e Astronomicas in 1877, the Lisbon Royal Academy of Sciences, founded in 1779, was the main publisher in Portugal of periodicals that included mathematical papers. In this article I will give an overview of the mathematical papers which appeared in the Academy's Memoirs during the 19th century, in the context of the scientific output published in its pages. We will characterize the community of mathematicians around the Academy's journal and the changes in background and in themes researched throughout the century. 相似文献
108.
第29届奥运会中外男篮技术成绩统计分析 总被引:1,自引:0,他引:1
本文对第29届奥运会中国男篮同相遇对手的技术成绩指标,进行了相关性、偏相关、回归分析等多元统计分析,通过回归方程找出影响总得分的主要因素,利用多因变量的线性模型对29届中国队与对手整体上进行比较,并对中国队在28、29两届上进行了整体的比较。结果显示:29届奥运会上中国队和对手在整体水平上有一定的差异;和28届相比,中国队前后差异不大,说明中国男篮进步幅度不是太大。 相似文献
109.
A Transfer Principle in the Real Plane from Nonsingular Algebraic Curves to Polynomial Vector Fields
Rudolf Winkel 《Geometriae Dedicata》2000,79(1):101-108
For every nonsingular algebraic curve C of degree m in the real plane a polynomial vector field of degree 2m–1 is constructed, which has exactly the ovals of C as attracting limit cycles. Therefore, every progress on the algebraic part of Hilbert's 16th problem automatically yields progress on its dynamical part. 相似文献
110.
T. M. Gendron 《Bulletin of the Brazilian Mathematical Society》2006,37(1):49-87
This paper introduces a notion of fundamental group appropriate for laminations. 相似文献