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581.
《Quaestiones Mathematicae》2013,36(4):533-549
AbstractThe bipartiteness of a graph is the minimum number of vertices whose deletion from G results in a bipartite graph. If a graph invariant decreases or increases with addition of edges of its complement, then it is called a monotonic graph invariant. In this article, we determine the extremal values of some famous monotonic graph invariants, and characterize the corresponding extremal graphs in the class of all connected graphs with a given vertex bipartiteness. 相似文献
582.
《Quaestiones Mathematicae》2013,36(5):687-699
AbstractIn the paper, joint universality theorems for periodic zeta functions with multiplicative coefficients and periodic Hurwitz zeta-functions are proved. The main theorem of [11] is extended, and two new joint universality theorems on the approximation of a collection of analytic functions by discrete shifts of the above zeta-functions are obtained. For this, certain linear independence hypotheses are applied. 相似文献
583.
《Analytical letters》2012,45(10):1570-1577
This paper describes a novel batch-type quartz crystal microbalance immunosensor that incorporates a commercially available stainless-steel holder. The sensor was coated with a hydrophilic polymer interface containing phosphatidylcholine analogs that attract water and amino groups for the covalent attachment of receptors. The hydrophilic polymer on a gold substrate captured antibodies and reduced nonspecific adsorption. Operation of the immunosensor required only one sample injection. A clear response triggered by antigen-antibody binding was observed and allowed measurement of the IgG antibody concentration with a superior signal-to-noise ratio using only commercially available components. We thus demonstrate an inexpensive and readily available sensor. 相似文献
584.
《Analytical letters》2012,45(10):1629-1637
The determination of trace elements in human fluids facilitates the identification of metabolic disorders and physiological abnormities in clinical diagnosis. Elemental concentrations in serum, urine, and saliva are often low and highly prone to contamination. Consequently, a simple and ultrasensitive detection technique is required. In this study, a method was developed for the simultaneous determination of trace arsenic and antimony in clinical samples by hydride generation atomic fluorescence spectrometry. The experimental parameters that affect the generation, delivery, and atomization of volatile arsenic and antimony hydrides were investigated. The limits of quantification were calculated to be 0.0037 nanogram per milliliter and 0.0070 nanogram per milliliter for arsenic and antimony, respectively. The method was successfully applied for the analysis of fortified human serum, urine, saliva, and certified reference materials. The results obtained by the reported method were not statistically different from the certified values at the 95 percent confidence level. 相似文献
585.
《Analytical letters》2012,45(16):2509-2519
Abstract The sources of uncertainty in the determination of copper, cobalt, cadmium, and nickel, originating from the flame atomic absorption spectrometer, were studied. They were identified and divided in three main groups according to their origin—from the flame, from the light source (hollow-cathode lamp), and from the optics. The combined uncertainty of the flame atomic absorption determination was experimentally determined. 相似文献
586.
ABSTRACTThe purpose of this note is to describe the mathematics that emanates from the construction of an origami box. We first construct a simple origami box from two rectangular sheets and then discuss some of the mathematical questions that arise in the context of geometry and algebra. 相似文献
587.
588.
《Applicable analysis》2012,91(1):75-85
ABSTRACTWe present a coincidence theory for set-valued maps which satisfy certain compactness-type conditions on countable sets. Our theory is based on fixed point results for compositions of set-valued self maps. 相似文献
589.
《Applicable analysis》2012,91(1):121-132
ABSTRACTIn this paper, we first study the smoothing properties of the attenuated Radon transform with complex-valued coefficients. Then on the basis of the framework of Sobolev spaces and the method of the approximate inverse, we derive a reconstruction algorithm. Finally, we extend the results of Rigaud and Lakhal to the attenuated Radon transform with complex-valued coefficients. 相似文献
590.
《Optimization》2012,61(3):321-322
In this article we establish necessary conditions for local Pareto and weak minima of multiobjective programming problems involving inequality, equality and set constraints in Banach spaces in terms of convexificators. 相似文献