NEW
CHEMICALS REAGENTS
CHEMICALS
MATERIALS Cesium Chloride
A new cesium chloride is especially prepared for ultracentrifuge separation of macromolecules. It has an optical density of 0.06 at 260 πΐμ in a 60% aqueous solution, in contrast with pre viously available material with an op tical density of about 0.70. GallardSchlesinger Chemical Mfg. Corp., 1001 Franklin Ave., Garden Citv, L. Ι., Ν. Υ. 501 Tin Radioisotope Tin-119m, a radioisotope with high specific activity is newly available. It is widely used as a Mossbauer effect source, and the increased specific ac tivity extends its usefulness in this ap plication. Nuclear Science and Engi neering Corp., Pittsburgh 36, Pa. 502 Powdered Teflon A non-staining, dry-lubricating pow der, Fluoro-Glide 200, is available for use in laboratories as an aid in instru mental mechanisms. The material is white with a 10-micron average particle size, and offers the expected resistance to solvents and acids of Teflon prod ucts. The powder is supplied in a con venient squeeze bottle. Chemplast, Inc., 3 Central Avs., East Newark, N. J. 503
with the new prices. New England Nuclear Corp., Boston 18, Mass. 505 Radioactivity Standards
Four new radioactivity standards— calcium-45, chlorine-36, iodine-125, and cerium-139—are available from the Na tional Bureau of Standards. Five radium rock standards, krypton-85, and contemporary carbon for radiocarbon dating have been re-issued as standards. Calcium-45 (Sample No. 4942, $38) is issued as a solution of calcium chlo ride in hydrochloric acid and has a nominal activity of 8 X 104 d.p.s./ml. Iodine-125 (Sample No. 4944, $24) is issued as a 5-ml. solution with a nominal activity of 3 Χ 104 d.p.s./ml. Chlorine-36 (Sample No. 4943, $26) is supplied as a solution of sodium chlo ride in water, and has a half life of 3 Χ 105 years. Cerium-139 (Sample No. 4999, $32) is issued as a solid point source.
Krypton-85 (Sample No. 4935, $23) is supplied as 10 ml. of gas. Contemporary carbon is issued as 1 lb. of oxalic acid at a price of $4. Orders for radioactivity standards should be sent to Miss E. Zandonini, Radioactivity Standard Samples, Ra dioactivity Section, National Bureau of Standards, Washington 25, D. C. Hydrocarbon Standards
The American Petroleum Institute has announced the availability of two new hydrocarbon standard samples. They are: l-trans-2, cis-3, transAtetramethyl-cyclopentane and 1-methyl-3-ethyl-5-iert-butylbenzene. These samples are supplied as 5-ml. ampoules at $65 each. A full list of all available standard hydrocarbons may be ob tained by writing Beveridge J. Mair, Carnegie Institute of Technology, Pe troleum Research Laboratory, Pitts burgh 13, Pa.
No surface glaze or coating
Sulfhydryl Kit A sulfhydryl kit is available which provides a battery of reagents useful for detecting sulfhydryl groups of vary ing reactivities in proteins. The kit contains one gram each of the follow ing: p-chloromercuribenzoate, iodoacetic acid, iodoacetamide, iV-ethyl maleimide, acrylonitrile, dinitrofluorobenzene, o-iodosobenzoic acid, S-carboxymethyl cysteine, S-carboxyethyl cysteine; 500 mg. of cysteinyl-succinic acid; 50 ml. of β-mercapto ethanol; 250 mg. of S-DNP-cysteine; and 10 g. of ethyl amine. Gallard-Schlesinger Chemical Mfg. Corp., 1001 Franklin Ave., Garden City, L. Ι., Ν. Υ. 504 C a r b o n - 1 4 and Tritium Compounds
Across the board reductions in prices of all carbon-14 and tritium labeled compounds have been announced. A new catalog, Schedule K, lists over 300 carbon-14 labeled compounds and more than 100 tritium labeled compounds
Alberene Stone has a surface that goes all the way thru
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for 75 years the only perma nently satisfactory material for chemical laboratory table tops, shelving, sinks, splash backs, drain boards and fume hoods. Prompt delivery. ALBERENE S T O N E - A DIVISION OF THE GEORGIA M A R B L E COMPANY. For FREE l i t e r a t u r e and t e c h n i c a l assistance address: THE ALBERMAR COMPANY, 386 PARK AVE. SOUTH, NEW YORK 16, N. Y., DEPT. C. Circle No. 17 on Readers' Service Card VOL.
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