The19F(n, 2n)18F reaction has been adapted to the analysis of fluorochemical-treated fabrics, using Teflon film as the reference standard.
The ultimate success of the technique depends on effective retention of active recoil18F nuclei which can escape from both the fabric and the Teflon standards; this is accomplished by sealing all samples individually
in thin Mylar film before activation. Recoil protons produced in the fabric substrate create a measurable amount of18F in the basic unfinished fabric through the18O(p, n)18F reaction this compensates for systematic deficiencies encountered in measurement of the total18F-activity of the finished fabric.
Authors:Eleni Fragkiadaki, Georgios Evangelidis, Nikolaos Samaras, and Dimitris A. Dervos
-index) (Katsaros et al. 2007 ), and, (f) not only the citations inside the Hirsch-core but also the ones received by publications currently not included in the Hirsch-core (tapered h-index) (Anderson et al. 2008 ).
There have been some variations of the g
Authors:E. Búriová, F. Macášek, F. Melichar, M. Kropáček, and L. Procházka
To control virtually the toxic compounds and to improve quality control of the solution of 2-deoxy-2-[18F]fluoro-d-glucose (2-[18F]FDG), the products of its autoradiolysis were analyzed by high-performance liquid chromatography with electrospray mass spectrometric and radiometric detectors (HPLC/MS/RAD), thin layer chromatography on TLC silica plate and HPTLC on amino modified silica plate. Except Kryptofix™ 2.2.2, glucose and fluoride anion, no by-products and impurities were observed by LC/MS analysis of fresh 2-[18F]FDG samples. The analysis performed in the time interval of 6 to 48 hours after the end of 2-[18F]FDG synthesis indicated that the activity of the autoradiolysis products separated by HPLC did not exceed 1.3%. As the main autoradiolysis products of 3.3 . 10-5 to 4.4 . 10-5M 2-[18F]FDG solution of original specific activity 0.5-1.5 GBq . cm-3 were established: arabinose - 2.8 μM (G= 0.07/100 eV), gluconic and glucuronic acids 1.8-0.5 μM (G =0.01-0.05/100 eV), arabinose and araburonic acids occurred under 0.5 μM concentration at residual glucose contents about 0.14 mM. Radiation chemical yields of active products were calculated from molar activity of 2-[18F]FDG and the percentage of their activity: 0.5% radiochemical yield of 2-[18F]fluoroglucuronic acid corresponds to the G = 0.004/100 eV and 0.3% yield of 2-[18F]fluorogluconic acid issues G = 0.003/100 eV.
Authors:F. Könczöl, D. Lőrinczy, Zs. Vértes, G. Hegyi, and J. Belagyi
Chemical cross-links which covalently connected the Cys-374 and Glu-41 residues of adjacent monomers in the same strand of
F-actin were used to follow the consequences of the modification for the motional and structural properties of the actin filaments.
DSC measurements reported that the inter-monomer cross-links shifted the thermal transition temperature and affected strongly
the cooperativity of the transition in comparison with uncross-linked F-actin. Addition of HMM to F-actin induced significant
decrease of the transition temperature to lower value from 69.4 to 67. 5 °C.