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Radionuclide-based Diagnosis and Therapy of Prostate Cancer
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Sven-Erik Strand, Mohamed Altai, Joanna Strand, David Ulmert
Halogens include elements of the group 7 of the periodic table (fluorine, chlorine, bromine, iodine, and astatine) as well as their isotopes. Radioiodine isotopes can be directly incorporated in the targeting agents through existing tyrosine or histidine residues (see Figure 19.11). Radioiodine isotopes (124I, 123I, 125I and 131I) are usually provided in a salt form (I-) with a -1 valency. Oxidation of iodine, using oxidizing agents (Chloramine-T [32], Iodogen [33]), to the more reactive, electrophilic I+ (+1 valency) initiates its reaction with activated electron-rich aromatic rings such as that present in the amino acid tyrosine. Reaction with other amino acids bearing electron-rich aromatic rings (phenylalanine, tryptophan, and histidine) is also possible, but less likely.
Technetium-99m metastable radiochemistry for pharmaceutical applications: old chemistry for new products
Published in Journal of Coordination Chemistry, 2019
Bianca Costa, Derya Ilem-Özdemir, Ralph Santos-Oliveira
The chemical element technetium whose symbol is Tc has atomic number 43 and is located in group 7 (7B) of the periodic table. All isotopes of technetium are radioactive. The two most prevalent isotopes are 99mTc formed from the decay of 99Mo and 99Tc, the decay product of 99mTc. 99Tc (βmax: 274 keV) is a significant by-product of U-235 fission (6% thermal neutron yield). With a half-life of 2.1 × 105 years, 99Tc can build up in the environment and can be obtained in macroscopic quantities. In the metallic form, 99Tc is a transition metal, silvery gray. Like the other transition metals, 99Tc presents peculiar properties, such as varied colors, various oxidation numbers and different coordination numbers, which result from the existence of a sub-level “d” partially filled in the valence layer [11].
Manganese and trace element removal from New Zealand coal mine drainage using limestone leaching beds
Published in New Zealand Journal of Geology and Geophysics, 2019
Hannah Christenson, James Pope, Dave Trumm, Nigel Newman, Ivan Blanco, Gemma Kerr, Mike Young, Ben Uster
Manganese (Mn) is a group 7 transition metal and a common component of mine drainages (Cravotta 2008a, 2008b, Pope et al. 2010). Trace concentrations of Mn are required for biochemical processes, however high concentrations can have damaging ecological effects (Nyberg et al. 1995). Therefore, legislation setting concentration limits and regulating release of Mn to waterways has been introduced in a number of countries. In Brazil, a maximum 1 mg/l Mn limit exists for waste water, and in New Zealand trigger values of 1.3–3.6 mg/l are used for various levels for protection of aquatic systems (ANZECC 2000; Silva et al. 2010). Examples of mine influenced waters on the West Coast of New Zealand have Mn concentrations up to 13 mg/l, reaching four orders of magnitude above background Mn concentrations (Pope 2010), and exceeding national water quality guidelines. Treatment of Mn-rich water is frequently required prior to discharge into aquatic environments to comply with regulations.
Qualitative models of intramolecular dynamics of acetylene: relation between the bending polyads of acetylene and perturbed Keplerian systems
Published in Molecular Physics, 2018
D. A. Sadovskií, B. I. Zhilinskií
The spatial symmetry group7 of CH is . Combining it with time reversal or, more concretely, momentum reversal , we obtain the full symmetry group of the original 4-oscillator system. Reduction removes the continuous component of this group: the image of under the symmetry reduction map is an order eight Abelian group which is isomorphic to an abstract group and to the point group . We give its characters in Table 1.