The oxidation of Nb-silicide-based alloys is improved with Al, Cr, Ge or Sn addition(s). Depending on addition(s) and its(their) concentration(s), alloyed C14-AB₂ Laves and A15-A₃X phases can be stable in the microstructures of the alloys. In both phases, A is the transition metal(s), and B and X respectively can be Cr, Al, Ge, Si or Sn, and Al, Ge, Si or Sn. The alloying, creep and hardness of...

We investigate the values of several types of Dirichlet series D(s) for certain integer values of s, and give explicit formulas for the value D(s) in many cases. The easiest types of D are Dirichlet L-functions and their variations; a somewhat more complex case involves elliptic functions. There is one new type that includes ∑∞ n=1(n +1) for which such values have not been studied previously. 2...

BACKGROUND To compare mental health and well-being in different levels of the perceived discrimination among Iranian people living in Tehran. METHOD Using multi-stage sampling, 1255 subjects with the average age of 45 years and 9 months (including 672 women and 583 men) were selected and they completed all items of the general health questionnaire (GHQ), the social well-being inventory (SWI),...

Let Ω be a space with probability measure μ for which the notion of symmetry is defined. Given A ⊆ Ω, let ms(A) denote the supremum of μ(B) over symmetric B ⊆ A. An r-coloring of Ω is a measurable map χ : Ω → {1, . . . , r} possibly undefined on a set of measure 0. Given an r-coloring χ, let ms(Ω;χ) = max1≤i≤r ms(χ (i)). With each space Ω we associate a Ramsey type number ms(Ω, r) = infχ ms(Ω;χ...

Let G be a collection of graphs with n vertices. We present a simple description of [G]χ = {H ∈ G : χ(H) = χ(G)} where χ denotes the Randić index. We associate to G a Q-linear map ρ : Qm → Qk (for some integers k, m depending on G) such that the kernel of ρ contains the necessary information to describe [G]χ in terms of linear equations. These results provide precise tools for analyzing the beh...