Thomas Graham


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Graham, Thomas,

1805–69, Scottish chemist, best known for research in diffusiondiffusion,
in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life processes.
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 in both gases and liquids that led to his formulation of Graham's law. His discovery that certain substances (e.g., glue, gelatin, starch) pass through a membrane more slowly than others (inorganic salts, e.g., common salt, or sodium chloride) led him to draw a distinction between the two groups, calling the former (the slower) colloids and the latter crystalloids. In this connection he discovered dialysis. His work was the earliest in colloidal chemistry. His investigation of phosphoric acid led to the present chemical concept of polybasic acids.

Graham, Thomas

 

Born Dec. 20, 1805, in Glasgow; died Sept. 11, 1869, in London. British chemist; one of the founders of colloid chemistry.

From 1837 to 1855, Graham was a professor at University College, London, and later director of the mint. In 1836 he was made a fellow of the Royal Society. Graham was one of the founders of the London Chemical Society, and he was elected its first president in 1841. In 1829, Graham discovered the law that the rate of diffusion of a gas is inversely proportional to the square root of its density. In 1833 he disproved, on the basis of the three forms of phosphoric acid (ortho, pyro, and meta), the view that all acids are monobasic. He established the presence of internal friction in gases (1846–49). In 1861 he showed that, according to their capacity to diffuse through a parchment membrane (dialysis), all substances fall into one of two classes—crystalloids or colloids.

WORKS

“On the Law of Diffusion of Gases.” Transactions of the Royal Society of Edinburgh, 1834, vol. 12.

REFERENCE

Moore. F. J. Istoriia khimii. Moscow-Leningrad. 1925. Pages 142— 45. (Translated from English.)
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Cardiff-based Thomas Graham now employs more than 20 solicitors and will soon see total staff numbers pass the 50 mark.
Mr Bromhead said, 'I'm looking forward to working with the team at Thomas Graham and concentrating on the local property market and assisting with the firm's further expansion.'
Matthew Edgar, who plays Jamie, was joined by Thomas Graham, also known as Robert, and Joseph McCabe, who plays Kevin, to kick off the celebrations by signing autographs and having their pictures taken in the playground.
Results from the second preliminary: Preliminary round: Alan Hirst 31 Richard Punshon 27, Michael Sweeney 31 Harry Ellis 12, Liam Fallas 29 Keith Womersley 31, Jack Dyson 30 Martin J Sykes 31, Mark Wood 31 Andy Smith 11, Frank Greenwood 25 Peter Hopkinson 31, Bryan Dyson 28 Mick Turner 31, Ross Mallinson 29 James Martin 31, Thomas Graham 31 Jim Baxter 14.
Fellow stars Thomas Graham, who has played Robert in Byker Grove for four years, and Matthew Edgar, who plays Jamie, will also be there on the day.
Second qualifying draw: (odds in brackets) A) Alan Hirst (100) v Richard Punshon (66), Michael Sweeney 14) v Harry Ellis (100), Liam Fallas (20) v Keith Womersley (100), Jack Dyson (off 1) (5) v Martin J Sykes (25), Mark Wood (14) v Andy Smith (100), Frank Greenwood (off 1) (20) v Peter Hopkinson (100), Bryan Dyson (100) v Mick Turner (40), Ross Mallinson (66) v James Martin (33), Thomas Graham (33) v Jim Baxter (110).
Actors Daymon Britton, Nisha Joshi, Thomas Graham, Sammy Dobson, Matthew Edgar and twins Alex and Dominic Beebe met youngsters at the pool and took a dip too.
Teenager Thomas Graham is a comparatively old hand at stage shows.
Byker Grove stars Daymon Britton, Nisha Joshi, Thomas Graham, Sammy Dobson, Matthew Edgar and twins Alex and Dominic Beebe all met the youngsters and took a dip in the pool alongside them.
Thomas Graham, 34, almost caused a pile-up when he slammed on the brakes after overtaking the coach carrying youngsters from Linwood's Riverbrae School.