ধাতব পদার্থ
(1) A hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite
(2) A hard gray lustrous metallic element that is highly corrosion-resistant
(3) Occurs in niobite and fergusonite and tantalite
(1) A second element, tantalum , is always present in these minerals along with niobium.
(2) The initial spark was a press release from the Tantalum-Niobium International Study Centre calling for a boycott of tantalum mined illegally in world heritage sites in the Congo.
(3) Many rare but technologically important elements, such as tantalum and uranium, continue to be mined from poor regions of the world under conditions that some consider pernicious and hazardous.
(4) Magnesium, titanium, zirconium, niobium, tantalum , molybdenum and tungsten may be soldered if they are plated with a solderable metal coating such as silver.
(5) With the cell phone industry booming, the park's resources and wildlife are under massive strain from miners seeking colombo-tantalite, also known as coltan or tantalum .
(6) The experimental results have shown proposed constructive solutions to accomplish electron-ion powder heating with following particles deformation at a tantalic target.
(7) The catalyst has a support of niobic acid, tantalic acid or a mixture of niobic acid and tantalic acid or a support containing such acids.
(8) Tantalum is etched by peroxide - the same way it etches tungsten or titanium - by forming its mineral acid, in this case tantalic acid.
(9) Many contemporary chemists believed niobium and tantalum were the same elements until 1844 and later 1866 when researchers showed that niobic and tantalic acids were different compounds.
(10) The freshly precipitated tantalic acid was soluble in a hot oxalic acid aqueous solution, and it was quite stable against hydrolysis.
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