Using radiocarbon: an update

Antiquity ◽  
1994 ◽  
Vol 68 (261) ◽  
pp. 838-843 ◽  
Author(s):  
Sheridan Bowman
Keyword(s):  

A note in the 1990 ANTIQUITY volume dealt with four issues crucial to the successful use of radiocarbon in archaeology (Bowman & Balaam 1990): selection and characterization of material and context; determination of the radiocarbon result and error term; interpretation and publication; and strategic resourcing. Since then much has been published, particularly on quality control of radiocarbon measurements (‘determination’), and on the calibration of radiocarbon results (‘interpretation’). Here is an update.

1974 ◽  
Vol 96 (3) ◽  
pp. 839-844 ◽  
Author(s):  
G. F. Weissmann ◽  
B. C. Wonsiewicz

Spring materials are purchased under specifications which impose limits on the tensile strength but do not control the crucial properties, i.e., resistance to plastic flow and stiffness. Present techniques for characterizing spring material are discussed in detail. A novel test is described which is quick, inexpensive, and reliable and holds promise for both research and quality control applications. The test is based on a dynamic determination of energy dissipation in a sample stressed in bending or torsion, the usual modes of deformation for most springs. Stiffness and permissible deformations are determined directly and the elastic modulus and yield strength can be calculated easily. The results obtained in this way compare favorably with those determined by tensile testing. An example is given which illustrates the operation of the test and the calculation of results. Since the entire test from sample preparation to calculation of results requires about five minutes, and since the apparatus should be relatively inexpensive, the test ought to find application in many areas where testing is not practical at the present time.


Author(s):  
Kaushik Sanyal ◽  
Buddhadev Kanrar ◽  
Shiny S Kumar ◽  
Sangita Dhara Lenka

Accurate and precise determination of plutonium and uranium in fast breeder reactor fuels is one of the most important steps in the chemical quality control of these fuels. Along with...


2020 ◽  
Vol 11 (1) ◽  
pp. 93-99
Author(s):  
Abu Zakir Morshed ◽  
Sheikh Shakib ◽  
Tanzim Jahin

Corrosion of reinforcement is an important durability concern for the structures exposed to coastal regions. Since corrosion of reinforcement involves long periods of time, impressed current technique is usually used to accelerate the corrosion of reinforcement in laboratories. Characterization of impressed current technique was the main focus of this research,which involved determination of optimum chloride content and minimum immersion time of specimens for which the application of Faraday’s law could be efficient. To obtain optimum chloride content, the electrolytes in the corrosion cell were prepared similar to that of concrete pore solutions. Concrete prisms of 200 mm by 200 mm by 300 mm were used to determine the minimum immersion time for saturation. It was found that the optimum chloride content was 35 gm/L and the minimum immersion time for saturation was 140 hours. Accounting the results, a modified expression based on Faraday’s law was proposed to calculate weight loss due to corrosion. Journal of Engineering Science 11(1), 2020, 93-99


2008 ◽  
Vol 2 (2) ◽  
pp. 155-177 ◽  
Author(s):  
Eugene Brently Young
Keyword(s):  

Eternal return is the paradox that accounts for the interplay between difference and repetition, a dynamic at the heart of Deleuze's philosophy, and Blanchot's approach to this paradox, even and especially through what it elides, further illuminates it. Deleuze draws on Blanchot's characterisations of difference, forgetting, and the unlivable to depict the ‘sense’ produced via eternal return, which, for Blanchot, is where repetition implicates or ‘carries’ pure difference. However, for Deleuze, difference and the unlivable are also developed by the living repetition or ‘contraction’ of habit, which results in his distinctive characterization of ‘force’, ‘levity’, and sense in eternal return.


2019 ◽  
Author(s):  
Chem Int

Recent study was conducted to develop a simple UV spectrophotometric method to determine Phenytoin in bulk and injection form according to official requirement and validate as per ICH guidelines. λmax of Phenytoin was found 202 nm. Linearity existed perceived in the concentration assortment 2-8 μg/ml (r2 = 0.999) for the method. The method was validated pertaining to linearity, precision and accuracy studies, LOD and LOQ consistent with ICH guidelines. The existent method was establish to be simple, linear, precise, accurate as well as sensitive and can be applied for routine quality control enquiry for the analysis of Phenytoin in bulk and injection form.


2018 ◽  
Author(s):  
D. Basak ◽  
L. H. Ponce

Abstract Two case-studies on uncommon metals whiskers, performed at the Reliability Analysis Laboratory (RAL) of Northrop Grumman Innovation Systems, are presented. The components analyzed are an Oven Controlled Crystal Oscillator (OCXO) and an Electromechanical Relay. Investigative techniques were used to determine the chemical and physical makeup of the metal whiskers and develop an understanding of the underlying effects and mechanisms that caused the conditions conducive to whisker growth.


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