Arsenic (atomic number, 33; relative atomic mass, 74.92) has chemical and physical properties intermediate between a metal and a nonmetal, and is often referred to as a metalloid or semi-metal. It belongs to Group VA of the Periodic Table, and can exist in four oxidation states: –3, 0, +3, and +5. Arsenite, AsIII, and arsenate, AsV, are the predominant oxidation states under, respectively, redu...

A density functional theory investigation has been presented in this work on M(5)H(5)X hydrometal pentagons (M = Ag, Au, Pd, P) with D(5)(h) planar pentacoordinate nonmetal centers (X = Si, Ge, P, S). The introduction of the nonmetal centers X introduces p aromaticity to M(5)H(5)X complexes. These novel planar complexes are favored in thermodynamics and confirmed to be aromatic in nature. They ...

ITO capped with a variety of ultra-thin metal layers such as platinum, manganese, nickel, gold, lead, magnesium, and nonmetal layer such as, carbon, gallium, silicon, has been used as hole-injecting anode in organic light-emitting diodes consisting of CuPc/TPD/Alq3. Enhancement in hole injection but not current nor power efficiencies have been obtained in devices with metalcapped ITO, regardles...

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  ...

The current s t a t e of the a r t of f i r e and smoke detect ion technology i s reviewed from the standpoint of s u i t a b i l i t y f o r use i n underground metal and nonmetal mines. Detection modes, f i r e signatures, and environmental considerat ions a r e included. Preliminary r e s u l t s of longterm, in-mine t e s t s a r e presented.

Constructing Ag-based photocatalysts by the incorporation of Ag(+) ions into metal/nonmetal oxides for removing organic pollutants is a recently developed strategy, but overcoming their own photocorrosion is still a tremendous challenge. In this work, an advanced Ag-based photocatalyst Ag2Ta4O11 is obtained by this strategy, which exhibits improved photocatalytic activity compared with Ta2O5 an...

The type of prosthetic restoration used in implant rehabilitation greatly contributes to the recovery of masticatory function as well as quality of life in patients. Frameworks for implant-supported prostheses are typically made by casting metal or milling either titanium or zirconia. Recently, nonmetal, polymer-type materials were suggested as framework materials. Polyetherketoneketone (PEKK),...

A first-principles self-consistent (non-muffin-tin) band-structure calculations on 1T-VSe, is used to analyze some of the transport and optical properties. The material appears to be metallic with characteristic overlaps between the metal d-based and nonmetal p-based bands. These overlaps are found to be sensitively modulated both by the change of the (anomalously high) c/a ratio and by the san...