The decomposition mechanism of C4F7N-Cu gas mixtures
AIP ADVANCES
Authors: Fu, Yuwei; Wang, Xiaohua; Yang, Aijun; Rong, Mingzhe; Zhu, Feng
Abstract
C4F7N is one of the most remarkable replacements for SF6, and its decomposition mechanism has a great influence on insulating performance and environmental properties. It is noteworthy that discharges or high temperature also evaporates metal electrodes (e.g., Cu) in the equipment, and the generated metal gases interact with C4F7N and thus affect the C4F7N decomposition mechanism, but the decomposition mechanism is still not clear. In this paper, therefore, the B3LYP method in conjunction with 6-311G(d, p) basis set (for C, N, and F atoms) and Lanl2DZ basis set (for Cu atom) combining transition state theory is used to study the decomposition mechanism of C4F7N-Cu mixtures. 31 reactions are determined in decomposition pathways of C4F7N-Cu mixtures, and their potential energy surface as well as reaction mechanisms are obtained. The rate constants over 300 K-3500 K relevant to the insulation breakdown temperature are calculated based on the above calculations, and dominant reactions in different temperature regions are selected. The results show that (R14) C4F7N + Cu -> CF3CFCN + CF2CuF plays a major role in the decomposition of C4F7N-Cu mixtures below 1500 K, while (R1) C4F7N + Cu -> TSa1 -> CuCN + C3F7 and (R21) C4F7N + Cu -> TSc1 -> CF3CF(CN)CF2 + CuF are dominant above 1500 K; (R23) CF3CF(CN)CF2 + Cu -> CF2 (Cu)C(F)CN + CF3 is the most important reaction leading to the generation of CF3 below 1500 K with the overwhelming rate constant, but other reactions also generating CF3 are dominant above 1500 K. (C) 2019 Author(s).
Genetics, genomics, and genotype-phenotype correlations of TSC: Insights for clinical practice
AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS
Authors: Peron, Angela; Au, Kit Sing; Northrup, Hope
Abstract
Tuberous Sclerosis Complex (TSC) is a multisystem autosomal dominant condition caused by inactivating pathogenic variants in either the TSC1 or the TSC2 gene, leading to hyperactivation of the mTOR pathway. Here, we present an update on the genetic and genomic aspects of TSC, with a focus on clinical and laboratory practice. We briefly summarize the structure of TSC1 and TSC2 as well as their protein products, and discuss current diagnostic testing, addressing mosaicism. We consider genotype-phenotype correlations as an example of precision medicine, and discuss genetic counseling in TSC, with the aim of providing geneticists and health care practitioners involved in the care of TSC individuals with useful tools for their practice.