Radiocarbon dating method development

The amount of information gathered over the decades since the radiocarbon dating method was developed is very extensive, so that even the briefest of reviews on the subject is out of the question here. The interested reader is referred, therefore, either to Radiocarbon, the periodical dedicated to the regular publication of new radiocarbon data, issued by the University of Arizona, or to one of the excellent reviews on the subject such as those by Hedges 2001 and by Lowe 1997. 

SINCE LIBBY S DEVELOPMENT of the radiocarbon dating method, which made the determination of absolute dates—or of dates with a known degree of precision—possible, archaeology has undergone a subtle and continuous transformation toward greater precision and reliance on quantitative data. Dating has become one of the milestones of modern ar-... 

The radiocarbon dating method was developed by Willard F. Libby and his coworkers James R. Arnold and Ernest C. Anderson between 1946 and 1949 at the University of Chicago. The now well-known physical model on which the method rests had been conceived by Libby during the period of his tenure with the Manhattan Project at Columbia University during World War II (1,2). The first critical test of the model... 

R.E. Taylor, History of radiocarbon dating, lecture presented at Radiocarbon in ecology and earth system science (http //ecology/botany/ufl/radiocarbon07/), University of California, Irvine (2006). (The first radiocarbon revolution is represented by the development of the dating method by Libby and his colleagues the second radiocarbon revolution is considered to be the introduc tion of calibration.)... 

As renewable raw materials began to enter the marketplace, it was inevitable that claims to the level of renewable content in commercial offerings would become an issue of public debate. As previously pointed out in this article, some renewable raw materials have been common to the polyol chemistry for many decades, so claims to at least some renewable content are justified. Because the commercialization of different renewable polyol chemistries has created a highly competitive environment, some scientists in the field have promoted a method for the independent verification of the renewable sourced carbon in the final product [153]. ASTM International has published a concise and informative briefing paper on the method development for the determination of renewable carbon content in carbon-containing substances [154]. The method involves the analysis of content in the finished polyurethane products via radiocarbon dating [155]. The technique is fast and accurate, and has become commonly available by contract analysis through independent analytical laboratories [156]. 

Radiocarbon dating is a technique used widely by archaeologists to date articles composed of organic material (e.g. wood), and the importance of the method was recognized in 1960 by the award of the Nobel Prize in Chemistry to its developer, W.F. Libby. The method relies on the fact that one isotope of carbon, gC, is radioactive (n = 5730 yr) and decays according to equation 2.34. 

Libby, Willard F., and Frederick Johnson. Radiocarbon Dating 2nd ed. Chicago University of Chicago Press, 1955. Dr. Libby was awarded the Nobel Prize in Chemistry in 1960 for the development of carbon dating methods. This book is Libby s story in his own words. 

One of the most interesting recent applications of radioactivity is the determination of the age of carbonaceous materials by measurement of their carbon-14 radioactivity. This technique of radiocarbon dating, which was developed by an American physical chemist, Willard F. Libby, permits the dating of samples containing carbon with an accuracy of around 200 years. At the present time the method can be applied to materials that are not over about 50,000 years old. 

Alongside developments in radiocarbon dating itself, comprehensive methods have been developed for the integration of chronological information into Bayesian age models. They are... 

Once the aggregate nature and the occurrence of other carbonate materials are estabhshed, the binder carbonates are separated by a combined mechanical and physical procedure (Ortega et al., 2008). This method removes the carbonate fraction, lime lumps and the charcoal particles. The extraction procedure allows to obtain binder reliable for dating without using partial acid digestion and several radiocarbon measurements of complex interpretation. In order to test the effectiveness of mechanical separation and to verify the purity of the binder. Scanning Electron Microscope (SEM), X-ray diffraction (XRD) analyses and thermogravimetric analysis (TGA) were performed. To test the developed procedure, historic lime mortars from the parish church of Santa Maria la Real (Zarautz, northern Spain) have been dated. 

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