Rl%UMl? 11 cst propod unc mdthode polarographlque dc dosage dc la tyrosme, du tryptophane et dc la phdnylalanine en pr&sence les uns des autrcs La m&ho& est spdclfique car les autres acides aminds ne g&ent pas la dCtermination amsi qu'en tdmoigne le dosage de la peptone Hoffmann-La Roche. La mdthode
Melting-points of commercial brasses and bronzes
- Publisher
- Elsevier Science
- Year
- 1914
- Tongue
- English
- Weight
- 53 KB
- Volume
- 177
- Category
- Article
- ISSN
- 0016-0032
No coin nor oath required. For personal study only.
โฆ Synopsis
Preparation of Metallic Tungsten. G. ERHARD. (Metallurgie, ix, 44I.)--This paper discusses the various methods of obtaining metallic tungsten, and the conclusion is reached that the preparation of tungstic acid is the best intermediate stage. The purified sodium "tungstate, obtained by fusion of the ore with 60 per cent. sodium carbonate, was treated with hydrochloric acid containing 6 per cent. of nitric acid, and the tungstic acid thoroughly washed to remove alkaline salts. After completely drying, ioo kilos, of tungstic acid were mixed with 14.1 kilos, of pure charcoal and 2 kilos, of rosin, and heated to 14oo ยฐ C. in a crucible the lid of which was carefully luted. The agglomerated metal was then finely ground and elutriated in the usual way, yielding a product containing 96.5 per cent. of pure metal.
๐ SIMILAR VOLUMES
Approximate Melting-Points of Some Commercial Copper Alloys. H.W. GILBERT and A. B. I'N'tORTON. (Amer. Inst. of Metals, Oct., I913.)--The alloys (except manganese bronze, in which case the previously made alloy was melted) were all made by melting together the constituents in the carborundum crucibl
BRONZE, AND ALU-~txu;.~r Baoxz~,; AXD BRASS.--'l'here have just been completed at theWaterwwn Arsenal some interesting tests of alloys, which the Government had ,.doted, with a view to getting the best possible material for the screws for the 5fieen or twenty new war ships now building. The results
## 203 Copper Alloy Resistant to Acids. ROBERT GRIMSHAW. (The Metal Industry, x, 12, 498.)--An alloy of 4o per cent. cobalt and 6o per cent. tin is especially resistant to acids, even to concentrated nitric acid and to this acid mixed with chlorides. It is, however, so brittle as to be unworkable,