Transition-metal-substituted  (TMS)  polyoxometalates  of  the  general  formula  [SiW9M3O39], (where M = first row transition metal), has been synthesized and supported on anatase by sol–gel method under oil-bath condition. The tetrabutylammonium (TBA) salts of the Keggin-type polyoxotungstates  [SiW9M3O39],  (M = VII, CrII, MnII,  FeII CoII  and NiII),  proved  to  be  green, reusable,  and  ...

There are some large scale orebodies that extend from surface to the extreme depths of the ground. Such orebodies should be extracted by a combination of surface and underground mining methods. Economically, it is highly important to know the limit of upper and lower mining activities. This concern leads the mine designers to the transition problem, which is one of the most complicated problems...

One of the most important factors influencing the track maintenance is the transitions between parts of the track with different vertical stiffness. The dynamic...

the mechanism by which bi-and trivalent cations affect human liver phosphatidatephosphohydrolase (pap) activity was investigated. bivalent cations up to 1 mm increased pap activity whereas at higher concentrations the activity of the enzyme decreased. the stimulatory concentration for trivalent cations such as al3+ and cr3+, however, was much lower being 2 m m and 1 m m, respectively. all catio...

In a structural time series regression model, binary variables have been used to quantify qualitative or categorical quantitative events such as politic and economic structural breaks, regions, age groups and etc. The use of the binary dummy variables is not reasonable because the effect of an event decreases (increases) gradually over time not at once. The simple and basic idea in this paper i...

polymer-graphite powder composite behaves as a low-conductive material which can be used as an automatic fuse for adhesive connector in electrical circuits. the conductivity of this composite, below its transition temperature, tt, depends on concentration of carbon powder, slowly decreases as the temperature increases. meanwhile, the electrical resistivity of this material in transition tempera...

The eigenvalues of the isotropic magnetic interaction system extraction from Internal Field Approximation (IFA) q e computed. on the basis of RKKY for the complicated magnetic behaviour of Gd, X system X= (Au , Pt , Al , In ) as well as Gd. From the strength and slope of eigenvalue curves in different ranges of interaction the strength and sharpness of the magnetic transition can be suggest...

Abstract The spontaneous emission spectrum from a driven three-level atom placed inside a double-band photonic crystal has been investigated. We use the model which assumes the upper levels of the atomic transition are coupled via a classical driving field. The transition from one of the upper levels to lower level couples to the modes of the modified reservoir, and the transition from the oth...