Transport Properties of Silicene Nanotube- and Silicene Nanoribbon-Based FETs

Silicene is one of the most interesting nanomaterials. In this chapter, computational studies have been done on Silicene nanotube and nanoribbon-based FETs to analyze their transport properties. The FET is designed from armchair nanoribbon and single wall nanotube. The scattering region is capped by a dielectric and a metallic layer to form a gate. The conductance versus gate bias voltage, conductance versus temperature up to 2000K, and electrode temperature versus current characteristics are calculated and plotted along with the design of the equivalent model of the structure. Extended Huckel-based calculations were used, and the analysis shows the transport properties of both structures.

Electrophysiology-based assessment of the procedural success of radiofrequency renal denervation

Objective To assess whether electrode temperature and impedance change that are typically monitored during radiofrequency renal denervation (RDN) for safety reason may also be used as measures of the procedural success of the intervention. Methods We conducted a prospective clinical study of the radiofrequency RDN in patients meeting criteria of true resistant hypertension. The RDN treatment included the trunk and major branches of the renal artery. To obtain simple easy-to-use electrophysiology measures of the procedural success of RDN we averaged the maximal values of the temperature and change of impedance across all single treatments with a full duration. Then we assessed the relation of the average change in impedance and average maximal electrode temperature during RDN to blood pressure (BP) lowering 6 month post-procedure using a linear regression analysis. Also, we compared the groups with “successful” and “unsuccessful” procedures according to whether the impedance decreased, on average, ≥10% during RDN, and, alternatively, on whether the average maximal temperature of the electrode was ≥50 C. Results Of 65 treated patients 52 with quality recordings of the electrophysiology parameters during RDN completed 6-month follow-up. The mean 24-h systolic BP decreased significantly after RDN by −14.3 mmHg [95% CI: −8.7; −19.9]. The BP lowering was positively and significantly related to the decrease in impedance during RDN, r=0.35, p=0.013 and to less extent to the maximal electrode temperature, r=0.29, p=0.044. The 10% average drop in impedance predicted -9.9 mmHg decrease in 24-h mean systolic BP. According to group analysis the decrease of mean 24-h systolic BP was powerful in those with average decrease in impedance ≥10% during RDN (“successful” procedure), but almost zero otherwise: −19.9 [95% CI: −13.7; −24.5] vs −0.5 [95% CI: −11.9; 12.9] mmHg, respectively (raw estimates), p=0.003. The difference in BP lowering was less pronounced and non-significant when the procedural “success” was defined according to the average maximal electrode temperature. Conclusions The impedance decrease during radiofrequency RDN treatment may be an effective criterion of the procedural success of the intervention. Guiding radiofrequency RDN by the impedance drop 10% or greater may significantly improve the efficacy of the procedure. Funding Acknowledgement Type of funding source: None

Transport Properties of Silicene Nanotube- and Silicene Nanoribbon-Based FETs

Silicene is one of the most interesting nanomaterials. In this chapter, computational studies have been done on Silicene nanotube and nanoribbon-based FETs to analyze their transport properties. The FET is designed from armchair nanoribbon and single wall nanotube. The scattering region is capped by a dielectric and a metallic layer to form a gate. The conductance versus gate bias voltage, conductance versus temperature up to 2000K, and electrode temperature versus current characteristics are calculated and plotted along with the design of the equivalent model of the structure. Extended Huckel-based calculations were used, and the analysis shows the transport properties of both structures.

Lithium-ion Battery Thermal Safety by Early Internal Detection, Prediction and Prevention

Temperature rise in Lithium-ion batteries (LIBs) due to solid electrolyte interfaces breakdown, uncontrollable exothermic reactions in electrodes and Joule heating can result in the catastrophic failures such as thermal runaway, which is calling for reliable real-time electrode temperature monitoring. Here, we present a customized LIB setup developed for early detection of electrode temperature rise during simulated thermal runaway tests incorporating a modern additive manufacturing-supported resistance temperature detector (RTD). An advanced RTD is embedded in a 3D printed polymeric substrate and placed behind the electrode current collector of CR2032 coin cells that can sustain harsh electrochemical operational environments (acidic electrolyte without Redox, short-circuiting, leakage etc.) without participating in electrochemical reactions. The internal RTD measured an average 5.8 °C higher temperature inside the cells than the external RTD with almost 10 times faster detection ability, prohibiting thermal runaway events without interfering in the LIBs’ operation. A temperature prediction model is developed to forecast battery surface temperature rise stemming from measured internal and external RTD temperature signatures.