A sensitivity analysis algorithm for hierarchical decision models

In this paper, a comprehensive algorithm is developed to analyze the sensitivity of hierarchical decision models (HDM), including the analytic hierarchy process and its variants, to single and multiple changes in the local contribution matrices at any level of the decision hierarchy. The algorithm is applicable to all HDM that use an additive function to derive the overall contribution vector. It is independent of pairwise comparison scales, judgment quantification techniques and group opinion combining methods. The allowable range/region of perturbations, contribution tolerance, operating point sensitivity coefficient, total sensitivity coefficient and the most critical decision element at a certain level are identified in the HDM SA algorithm. An example is given to demonstrate the application of the algorithm and show that HDM SA can reveal information more significant and useful than simply knowing the rank order of the decision alternatives.     

Determination of gold,palladium and copper by flame atomic absorption spectrometry after preconcentration on silica gel modified with 3-(2-aminoethylamino)propyl group

A preconcentration method of gold, palladium and copper based on the sorption of Au (III), Pd (II) and Cu (II) ions on a column packed with 3-(2-aminoethylamino)propyl bonded silica gel is described. The modified silica gel was synthesized and characterized by FT-IR and C, H, N elemental analysis. At column preconcentration, the effects of parameters such as pH, volume, flow rate, matrix constituents of solutions and type of eluent on preconcentration of gold, palladium and copper were studied. The recoveries of Au (III), Pd (II) and Cu (II) were 98.93±0.51, 98.81±0.36 and 99.21±0.42 % at 95 % confidence level, respectively. The detection limits (δ) of the elements were 0.032, 0.016 and 0.012 μg ml⁻¹, respectively. The preconcentration method was applied for determination of gold and palladium in certified reference material SARM 7B and copper in river and synthetic seawater by FAAS. Gold, palladium and copper were determined with relative error lower than 10 %.     

Design of Novel Binuclear Phthalocyanines formed by Dioxyphenyl Bridges: Synthesis and Investigation of Thermal and Antioxidant Properties

4, 4′‐(1, 4‐Phenylenebis(oxy)diphthalonitrile was synthesized by reaction of hydroquinone with 4‐nitrophthalonitrile. Binuclear metallophthalocyanines 2–4 were obtained by the reaction between 4, 4′‐(1, 4‐phenylenebis(oxy)diphthalonitrile and 4‐(benzo [d] 1 , 3 dioxol‐5‐ylmethoxy)phthalonitrile in the presence of metal salts. These new compounds were characterized by using elemental analysis, FTIR, ¹H‐NMR and UV/Vis spectroscopic data. Thermal properties of phthalocyanines 2‐4 were investigated by TG and DTA. In addition, antioxidant properties of compounds II , 3 and 4 were investigated. Their radical‐scavenging capacity and chelating effects was fully studied. The maximum 1, 1‐diphenyl‐2‐picrylhydrazyl radicals (DPPH) were obtained from compound 3 . Chelating effects on ferrous ions were 91.6 % at concentration of 100 mg L^–1 with compound II .     

Calculation of the Accessibility Number and the Neighbor Integrity of a Graph

We calculate stability numbers of Butterfly and Omega networks used in computer science.We describe relations between the neighbor integrity and the accessibility number of these networks.