Determination Of C14 Research Articles

DATING THE BRONZE AGE IN SPAIN

Summary. How can archaeologists combine and use C14 determinations when they have irregular recalibrated dates? This question is solved by an example with six determinations from the Bronze Age settlement of El Castillo in the mountains of eastern Spain. For the first time we can date precisely the end of the Eneolithic to 2150–2110 BC, and the start of a Bronze Age expansion stage by 1960 BC. Each has a distinctive material culture; that of the Bronze Age stage is linked closely to the climax of the Motillas in La Mancha, and more distantly to El Argar in SE Spain.

Ringkloster, en jysk indlandsboplads med Ertebøllekultur

Ringkloster, en jysk indlandsboplads med Ertebøllekultur

La Jolla Natural Radiocarbon Measurements VI

The following list of measurements contains selected results obtained by the La Jolla Radiocarbon Laboratory from November 1966 to July 1971. During the same period 382 measurements were made on tree-ring-dated wood in studying secular variations of the atmospheric C14 level and of the absolute radiocarbon time scale [Suess, 1970a, 1970b]. Results of these measurements are not included here. Also not included are 124 measurements of C14 determinations in extraterrestrial material and results of other occasional investigations will be published elsewhere.

DISTRIBUTION AND EXCRETION OF [14C]‐NEOSTIGMINE IN THE RAT AND HEN

British Journal of Pharmacology and ChemotherapyVolume 25, Issue 1 p. 234-242 Free Access DISTRIBUTION AND EXCRETION OF [14C]-NEOSTIGMINE IN THE RAT AND HEN J. B. ROBERTS, J. B. ROBERTS Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this authorB. H. THOMAS, B. H. THOMAS Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this authorA. WILSON, A. WILSON Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this author J. B. ROBERTS, J. B. ROBERTS Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this authorB. H. THOMAS, B. H. THOMAS Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this authorA. WILSON, A. WILSON Department of Pharmacology and General Therapeutics, University of LiverpoolSearch for more papers by this author First published: August 1965 https://doi.org/10.1111/j.1476-5381.1965.tb01778.xCitations: 19AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat REFERENCES Beyer, K. H., Russo, H. F., Gass, S. R., Wilhoyte, K. M. & Pitt, A. A. (1950). Renal tubular elimination of N'-methylnicotinamide. Amer. J. Physiol., 160, 311– 320. Bollman, J. L. (1948). A cage which limits the activity of rats. J. Lab. clin. Med., 33, 1348. Brittain, R. T. & Spencer, P. S. J. (1963). An apparatus for the long-term collection of urine free from faecal and food contamination. J. Pharm. Pharmacol., 15, 483– 485. Goldstein, A., Krayer, O., Root, M. A., Acheson, G. H. & Doherty, M. E. (1949). Plasma neostigmine levels and Cholinesterase inhibition in dogs and myasthenic patients. J. Pharmacol, exp. Ther., 96, 56– 85. Kelly, R. G., Peets, E. A., Gordon, S. & Buyske, D. A. (1961). Determination of C14 and H3 in biological samples by Schöniger combustion and liquid scintillation techniques. Analyt. Biochem., 2, 267– 273. Kinard, F. E. (1957). Liquid scintillator for the analysis of tritium in water. Rev. Sci. Instrum., 28, 293– 294. Krayer, O., Goldstein, A. & Plachte, F. L. (1944). Studies on physostigmine and related substances. 1. Quantitative relation between dosage of physostigmine and inhibition of Cholinesterase activity in the blood serum of dogs. J. Pharmacol. exp. Ther., 80, 8– 30. Nowell, P. T., Scott, C. A. & Wilson, A. (1962a). Determination of neostigmine and pyridostigmine in the urine of patients with myasthenia gravis. Brit. J. Pharmacol., 18, 617– 624. Nowell, P. T., Scott, C. A. & Wilson, A. (1962b). Hydrolysis of neostigmine by plasma Cholinesterase. Brit. J. Pharmacol., 19, 498– 502. Peters, L., Fenton, K. J., Wolf, M. L. & Kandel, A. (1955). Inhibition of the renal tubular excretion of N'-methylnicotinamide (NMN) by small doses of a basic cyanine dye. J. Pharmacol. exp. Ther., 113, 148– 159. Rennick, B. R., Kandel, A. & Peters, L. (1956). Inhibition of the renal tubular excretion of tetraethylammonium and N'-methylnicotinamide by basic cyanine dyes. J. Pharmacol, exp. Ther., 118, 204– 219. Roberts, J. B., Thomas, B. H. & Wilson, A. (1963). Excretion of neostigmine labelled with carbon-14 in urine. Nature (Lond), 200, 1330. Scott, C. A. (1962). An Investigation of the Metabolism of Neostigmine. Ph.D. thesis at the University of Liverpool. Scott, C. A., Nowell, P. T. & Wilson, A. (1962). An investigation of the metabolism of neostigmine in patients with myasthenia gravis. J. Pharm. Pharmacol., 14, 31– 33T. Sperber, I. (1946). A new method for the study of renal tubular excretion in birds. Nature (Lond), 158, 131. Sperber, I. (1948). The excretion of some glucuronic acid derivatives and phenol sulphuric esters in the chicken. Ann. roy. agric. Coll. Sweden, 15, 317– 349. Sperber, I. (1949). Investigations on the circulatory system of the avian kidney. Zool. Bidrag. f. Uppsala, 27, 429– 448. Citing Literature Volume25, Issue1August 1965Pages 234-242 ReferencesRelatedInformation

Improved Technique for the Determination of C14 and H3 by Combustion.

Improved Technique for the Determination of C¹⁴ and H³ by Combustion.

Decomposition of diethylstilboestrol in soil

The rate of decomposition of DES-monoethyl-1-C14 in soil was followed by measurement of C14O2 released. From 1.6 to 16% of the added C14 was recovered as C14O2 during 3 months. After six months as much as 12 to 28 per cent was released as C14O2. Determination of C14 in the soil samples after the experiments showed that the amount extractable with benzene decreased to a greater extent than would be expected from the production of C14O2 and that the amount extractable with water was increased when compared with that found shortly after the addition of DES. Addition of large amounts of DES (8%) did not inhibit the CO2 production from the soil. Experiments with γ-sterilized soil indicated that enzymes present in the soil are able to attack DES.

Die Vergletscherungen Neuseelands und die Frage ihrer Gleichzeitigkeit mit den europäischen Vereisungen (Berichte über eine Reise zum Studium des Pleistozäns auf der Südhalbkugel I.)

Abstract. The Pleistocene sequence of Wanganui (North Island of New Zealand) and the succession of glaciations in the South Island are shortly reviewed. The Last Glaciation and the Postglacial time in New Zealand were, as C14 determinations definitly show, contemporaneous with those of the Northern Hemisphere. If the Last Glaciation was contemporaneous on the two Hemispheres, then the older ones must also have been contemporaneous. This does not agree with the MILANKOVITCH-curve, which in the form, as it has been given by M., cannot have been the cause of the ice ages.

The simultaneous determination of C 14 and H 3 in the terminal groups of glucose

A method is described that permits the simultaneous determination of C14 and H3. The dimedon derivative of formaldehyde, which is soluble in toluene phosphor solution, was prepared from the position-6 group of glucose and contains its two hydrogens and carbon. The H3 and C14 activities were simultaneously measured in accord with the discriminator ratio method using a liquid scintillation counter. Two scintillation solvent systems were utilized. The yields were generally about 45 mg, representing 75% theory. (P.C.H.)

Natural Radiocarbon Measurements on Surface Water from the North Atlantic and the Arctic Sea

An apparatus for the extraction of carbon dioxide from 100 liters of sea-water using carbonate-free sodium hydroxide solution as absorbant liquid and its performance is described. A test series of 6 sea water samples is presented, on which natural C14 determinations are made and the results obtained are briefly discussed in relation to other age measurements on similar waters. The correlation between salinity and C14 activity is shown.

Rate of Formation of a Diagenetic Calcareous Concretion

ABSTRACT Age determinations by the C14 method have been made on the matrix and enclosed fauna of a Quaternary calcareous concretion from the shelf southeast of Cape Campbell, New Zealand. The results show that the concretion must have formed within 19,500 years, and probably within 7500 years. It appears to have grown in a calcareo-argillaceous sediment containing an abundant molluscan fauna. The classification of concretions, and the terminology applied to them, are discussed in this paper. The three categories recognised by Richardson (1921) are retained, but it is suggested that the terms contemporaneous, penecontemporaneous, and subsequent should be replaced by syngenetic, diagenetic, and epigenetic. The Cape Campbell concretion is considered to be diagenetic. C14 determinations on other Quaternary concretions should throw further light on the absolute rate of concretion-forming processes.

Direct determination of C14 and S35 in blood.

Abstract A direct mounting procedure suitable for radioactive assay of small blood samples has been described in detail and its reproducibility evaluated. Results obtained with this technique have been related to oxidative methods. The procedure has been extended to include samples in which both S 35 and C 14 are present. The basis of the counting schedule employed and the calculations required for determining the percentage of the activity contributed by each of the isotopes are discussed.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELED GLUCOSE

A procedure based on the work of Jackson and Hudson was developed for the degradation of methyl-α-D-glucopyranoside formed from 2 millimoles of glucose. Oxidation of the glucoside with periodic acid gave C-3 as formic acid and a dialdehyde which was converted to the strontium salt of D′-methoxy-D-hydroxymethyl diglycolic acid. The purified salt was hydrolyzed to glyoxylic and glyceric acids. The glyoxylic acid was isolated as the 2,4-dinitrophenylhydrazone (C-1 + C-2); this was decarboxylated by heat to give carbon dioxide from C-2. The glyceric acid was oxidized by periodate to give C-4 as carbon dioxide, C-5 as formic acid, and C-6 as formaldehyde. This degradation permitted the determination of C14 in each position of the glucose molecule, the activity in C-1 being determined by difference. The method was applied to glucose-1-C14 and a sample of glucose labeled in all positions with satisfactory results.

A CHEMICAL PROCEDURE FOR DETERMINATION OF THE C14-DISTRIBUTION IN LABELED GLUCOSE

A procedure based on the work of Jackson and Hudson was developed for the degradation of methyl-α-D-glucopyranoside formed from 2 millimoles of glucose. Oxidation of the glucoside with periodic acid gave C-3 as formic acid and a dialdehyde which was converted to the strontium salt of D′-methoxy-D-hydroxymethyl diglycolic acid. The purified salt was hydrolyzed to glyoxylic and glyceric acids. The glyoxylic acid was isolated as the 2,4-dinitrophenylhydrazone (C-1 + C-2); this was decarboxylated by heat to give carbon dioxide from C-2. The glyceric acid was oxidized by periodate to give C-4 as carbon dioxide, C-5 as formic acid, and C-6 as formaldehyde. This degradation permitted the determination of C14 in each position of the glucose molecule, the activity in C-1 being determined by difference. The method was applied to glucose-1-C14 and a sample of glucose labeled in all positions with satisfactory results.

Geochronology of the Deglacial and Neothermal Ages: A Discussion: De Geer’s Continuous Chronology: Or Stretched One with Interruptions

Dr. Antevs presents a lot of different facts, of which, as usual, many are correct, but others are misunderstood in several details. Concerning geological items in Scandinavian geology, he is not always up to date, and his conclusions are often misleading. That he rebukes my different datings is but a natural consequence of his discarding the whole of De Geer's chronological scheme, with its advanced methods of dating and consecutive results. Some main questions will be examined here. The radiocarbon test at Two Creeks, Wisconsin, as the starting point of my display, is the foremost object of his doubts. The whole method of C14 determinations, however, is taken up by America's most clever research men and practiced very critically--most of all, the special test at Two Creeks. As they were startled by the low figure of years obtained, they repeated the investigation several times. As the

A rapid semimicro method for the determination of C14.

Abstract A rapid semimicro method is described for the determination of C 14 in small samples of organic material. At least four samples per hour may be oxidized easily and the resultant C 14 O 2 trapped as BaCO 3 and prepared for counting. Samples as small as 0.2 mg. of carbon may be analyzed within the limits of counting error and weighing error of the barium carbonate samples.