Cooling Hydrogenated

Sodium trithionate, Na2Si06, can be made by oxidizing sodium thiosulfate with cooled hydrogen peroxide solution... 

GM has been working on a system that would cool hydrogen to -196°C at 1,000 psi. This would be less costly and reduce the boil off. 

On vaporising sulphur in a cooled hydrogen flame, or on passing feeble electric sparks through the vapour contained in a Geissler tube, a band spectrum is obtained consisting of a series of bands sharp on the... 

Under considerably increased pressure, or when strongly cooled, hydrogen sulphide and water can combine to form a crystalline compound of which the composition is probably II2S.6II20 if the temperature and pressure are allowed to revert to the normal conditions, the crystals at once dissociate into the constituent substances.6 An additive compound of methyl ether and hydrogen sulphide, (CH3)2O.H2S, melting at —148-5° C., is also capable of existence at low temperatures 7 although the nature of this compound may be allied to that of the additive compound with water, it appears more probable that the methyl ether compound is an oxonium salt. 

A cooling fan F is installed to keep the greased joints adjacent to the furnace cool. Hydrogen pressures are monitored with a Texas Instruments quartz Bourdon-tube pressure gage G. 

K. Kleinermanns, M. Gerhards and M. Schmitt, Electronic spectroscopy of aromatic molecules in jet-cooled hydrogen bonded clusters - structure and fluxionality, Her. Bunsen-Ges. Phys. Chem., 101 (1997) 1785-1798. 

Conversion to the para form takes place at a relatively slow rate and is accompanied by the release of heat. For each pound of rapidly cooled hydrogen that changes to the para form, enough heat is liberated to vaporize approximately 1.5 1b of liquid hydrogen. However, if a catalyst is used in the liquefaction cycle, para-hydrogen can be produced directly without loss from self-generated heat. 

Most 1,2,3-thiadiazines are tetrahydro derivatives that exist as the 1,1-dioxides.12 17 However, the novel, heterocyclic 8n -electron systems 4 and the corresponding 1,2,3-thiadiazines have been prepared.18 Reaction of the 2-chlorocycloalkene-l-carbaldehydes l12 with potassium thiocyanate in aqueous ethanol affords the 2-thiocyanatocycloalkene-l-carbaldehydes 2 which react in the usual fashion with hydrazines to furnish the hydrazones 3a, b. When the hydra-zones 3 a, b are dissolved in 70 % perchloric acid under ice-cooling, hydrogen cyanide is evolved and the 1,2,3-thiadiazinium perchlorates 4a, b crystallize within a short time. Addition of an excess of triethylamine to 4a liberates the 1,2,3-thiadiazine while treatment of 4b with methanolic potassium hydroxide solution furnishes 5 b. 

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