A new quantitative radiochemical separation procedure to determine Ir at 10−12 g/g level in geological samples by a long chain primary amine extraction

1989 ◽  
Vol 130 (2) ◽  
pp. 321-331 ◽  
Author(s):  
Kong Ping ◽  
Chai Chifang
Keyword(s):  
Radiochemical Separation ◽  
Primary Amine ◽  
Separation Procedure ◽  
Geological Samples ◽  
Radiochemical Separation Procedure ◽  
Long Chain

scholarly journals Radiochemical separation and purification of non-carrier-added silicon-32

2021 ◽  
Vol 109 (10) ◽  
pp. 735-741
Author(s):  
Mario Veicht ◽  
Ionut Mihalcea ◽  
Đorđe Cvjetinovic ◽  
Dorothea Schumann
Keyword(s):  
Radiochemical Separation ◽  
Half Life ◽  
Chemical Yield ◽  
High Energy ◽  
Time Span ◽  
Radiometric Dating ◽  
Separation Procedure ◽  
Separation And Purification ◽  
Wide Range ◽  
Radiochemical Separation Procedure

Abstract 32Si (T 1/2 = 153(19) y) is an extremely rare, naturally-occurring isotope that has been considered as a geochronometer suitable for radiometric dating over the time span from 100 to 1000 years ago – a time span that has proved rather difficult to explore in this manner. Past attempts to determine the 32Si half-life have resulted in a wide range of values possessing significant uncertainties because only low-activity samples could be made available for such measurements. Utilizing the 590 MeV ring cyclotron at PSI, megabecquerel quantities of 32Si have been produced by exposing metallic vanadium discs to high-energy protons in order to induce spallation. A radiochemical separation procedure has been successfully developed and applied to the irradiated discs as part of the SINCHRON project, based on a combination of ion-exchange and extraction resins. The process was shown to be reliable and robust with a high chemical yield. Radiochemically pure 32Si solutions with activity concentrations of up to several kBq/g can be produced to perform individual measurements (AMS, ICP-MS, LSC) for various studies. Thus, a careful redetermination of the 32Si half-life has become feasible to begin the first steps toward the confident implementation of this radionuclide for geochronological purposes.

Identification of long-chain tricyclic terpene hydrocarbons (C21–C30) in geological samples

1984 ◽  
pp. 496-498 ◽  
Author(s):  
Denis Heissler ◽  
Ruben Ocampo ◽  
Pierre Albrecht ◽  
Jean-Jacques Riehl ◽  
Guy Ourisson
Keyword(s):  
Geological Samples ◽  
Long Chain

scholarly journals Arsenic for potential diagnostic imaging and radiotherapy

2015 ◽  
Author(s):  
◽  
Anthony James DeGraffenreid
Keyword(s):  
Germanium Dioxide ◽  
Separation Procedure ◽  
Chemical Derivatization ◽  
Non Invasive ◽  
Radiochemical Separation Procedure ◽  
Foundational Work ◽  
Time Required ◽  
Targeting Vector ◽  
No Carrier Added

Targeted agents hold promise for non-invasive in vivo imaging, therapy, and monitoring of diseases. Foundational work focused on imaging and therapy of cancer has centered primarily on the use of 18F, 90Y, 99mTc, and 131I radionuclides. Use of these agents often requires conjugation to a biological targeting vector, a peptide or monoclonal antibody (mAb), to investigate biological processes. To truly be effective the physical properties of the radionuclide must be suitably matched to the time required for chemical derivatization, conjugation, to reach maximal uptake of the targeting vector at the targeting site. Radioisotopes of arsenic, 72, 77As, have half-lives well-matched for conjugation to peptides or mAbs. Even with favorable decay characteristics, production, and separation pathways, the ability to use radioarsenic has largely remained undeveloped. It is the aim of this work to address this issue through the identification and synthesis of no-carrier added radioarsenic complexes. Macroscopic synthesis of AsPh(S-Rn-S) precursors to no-carrier added 72,77AsPh(S-Rn-S) complexes, synthesis and no-carrier added radioarsenic labelling of a simple trithiol ligand, and two linkable trithiocyanate precursors, a carboxylic acid and “clickable” alkyne, are described in detail. The development of a radiochemical separation procedure to separate no-carrier arsenic, 77As, from a neutron irradiated germanium dioxide target, evaluation of a novel copper selective resin, and synthesis of any additional unmentioned compounds are found in the attached appendices.

A rapid single column separation scheme for high-precision Sr–Nd–Pb isotopic analysis in geological samples using thermal ionization mass spectrometry

2015 ◽  
Vol 7 (11) ◽  
pp. 4793-4802 ◽  
Author(s):  
Chao-Feng Li ◽  
Zhu-Yin Chu ◽  
Jing-Hui Guo ◽  
You-Lian Li ◽  
Yue-Heng Yang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Thermal Ionization Mass Spectrometry ◽  
Isotopic Analysis ◽  
Ionization Mass ◽  
Separation Procedure ◽  
Separation Scheme ◽  
Geological Samples ◽  
Column Separation ◽  
Single Column ◽  
Thermal Ionization Mass

In this study, a single-column separation scheme is compared with the traditional three-step separation procedure.

Polymer Morphology Revealed by Staining Techniques

1981 ◽  
Vol 39 ◽  
pp. 340-341
Author(s):  
A. C. Reimschuessel ◽  
V. Kramer
Keyword(s):  
Polymer Melt ◽  
Nylon 6 ◽  
Morphological Features ◽  
Negative Staining ◽  
Polymer Morphology ◽  
Crystallizable Polymer ◽  
Staining Techniques ◽  
Long Chain

Staining techniques can be used for either the identification of different polymers or for the differentiation of specific morphological domains within a given polymer. To reveal morphological features in nylon 6, we choose a technique based upon diffusion of the staining agent into accessible regions of the polymer.When a crystallizable polymer - such as nylon 6 - is cooled from the melt, lamellae form by chainfolding of the crystallizing long chain macromolecules. The regions between adjacent lamellae represent the less ordered amorphous domains into which stain can diffuse. In this process the lamellae will be “outlined” by the dense stain, giving rise to contrast comparable to that obtained by “negative” staining techniques.If the cooling of the polymer melt proceeds relatively slowly - as in molding operations - the lamellae are usually arranged in a radial manner. This morphology is referred to as spherulitic.

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