Recent advances in MXenes: from fundamentals to applications

The family of MAX phases and their derivative MXenes are continuously growing in terms of both crystalline and composition varieties. In the last couple of years, several breakthroughs have been achieved that boosted the synthesis of novel MAX phases with ordered double transition metals and, consequently, the synthesis of novel MXenes with a higher chemical diversity and structural complexity, rarely seen in other families of two-dimensional (2D) materials. Considering the various elemental composition possibilities, surface functional tunability, various magnetic orders, and large spin$-$orbit coupling, MXenes can truly be considered as multifunctional materials that can be used to realize highly correlated phenomena. In addition, owing to their large surface area, hydrophilicity, adsorption ability, and high surface reactivity, MXenes have attracted attention for many applications, e.g., catalysts, ion batteries, gas storage media, and sensors. Given the fast progress of MXene-based science and technology, it is timely to update our current knowledge on various properties and possible applications. Since many theoretical predictions remain to be experimentally proven, here we mainly emphasize the physics and chemistry that can be observed in MXenes and discuss how these properties can be tuned or used for different applications

Proton radioactivity half lives with Skyrme interactions

The potential barrier impeding the spontaneous emission of protons in the proton radioactive nuclei is calculated as the sum of nuclear, Coulomb and centrifugal contributions. The nuclear part of the proton-nucleus interaction potential is obtained in the energy density formalism using Skyrme effective interaction that results into a simple algebraic expression. The half-lives of the proton emitters are calculated for the different Skyrme sets within the improved WKB framework. The results are found to be in reasonable agreement with the earlier results obtained for more complicated calculations involving finite range interactions.Comment: 10 pages including 4 figures and 4 tables; Some typographical mistakes in text and in Eq.(8) are correcte

Enhanced UV and ethanol vapour sensing of a single 3-D ZnO tetrapod alloyed with Fe2O3 nanoparticles

Fabrication of multifunctional devices based on nano- and microstructures of a single semiconducting oxide is an important step for a better understanding of their maximum sensing properties and the base for the development of bottom-up nanotechnologies. In this work we have fabricated, for the first time devices based on a single or two interconnected ZnO tetrapods (T), doped with Fe and alloyed with Fe2O3 nanoparticles (NPs) and microparticles (MPs) in order to improve their sensing properties towards ultraviolet (UV) sensing and ethanol vapour (EtOH). Compared to pristine ZnO-T improved UV and gas sensing properties of Fe-doped ZnO-T were observed. By Fe2O3-alloying of Fe-doped ZnO-T further improvement in sensing properties was obtained with a reduced influence of the relative humidity (RH) on the sensing response. A gas sensing mechanism was proposed and discussed in detail based on the alloyed Fe2O3 NPs and MPs. The results presented here demonstrate the efficiency of doping and alloying of single ZnO microstructures with other semiconducting oxides to improve their sensing properties, including the decrease in influence of RH on the gas response and the rapidity of the sensors

Increasing incidence of multidrug resistant Pseudomonas aeruginosa in inpatients of a tertiary care hospital

Background:Pseudomonas aeruginosa is an important pathogen isolated from various clinical infections. The occurrence of multidrug-resistant (MDR) Pseudomonas aeruginosa strains is increasing worldwide and limiting our therapeutic options resulting in high mortality. We aim to study the incidence of multidrug resistant Pseudomonas aeruginosa in inpatients from various departments along with rate of nosocomial infections.Methods:A cross sectional study from January 1, 2013 to December 31, 2013. A total of 167 Pseudomonas aeruginosa were isolated from 764 clinical specimens. The isolates were identified by standard microbiological techniques. The antibiotic susceptibility was done by Kirby Bauer method.Results:The highest number of isolates were from pulmonary samples n=90 (53.89%) followed by pus n=48 (28.74%). Overall, 39 (23.36%) isolates were nosocomial. The nosocomial isolates were mainly isolated from department of surgery, orthopaedics, obstetrics & gynaecology followed by others. Among 167 isolates screened, 53 (31.73%) were found to be MDR (resistant to ≥3 classes of antipseudomonal agents). The resistance was most against cephalosporins [Cefepime (65.26%), cefotaxime (60.47%)], fluoroquinolones [Ciprofloxacin (46.1%), levofloxacin (31.87%)] aminoglycosides [Amikacin (37.72%), gentamicin (31.13%)] followed by ureidopenicillins and carbepenems. About 56.75% isolates were suspected Metallo β lactamases producers.Conclusion:The study suggests that the incidence of nosocomial infection by multidrug resistant Pseudomonas aeruginosa is increasing globally especially the Metallo Beta lactamases producing strains. So there is a continuous need of conduction of surveillance programmes to formulate rational treatment strategies to combat this emerging challenge.

Chalcogen Assisted Enhanced Atomic Orbital Interaction at TMDs - Metal Interface & Chalcogen Passivation of TMD Channel For Overall Performance Boost of 2D TMD FETs

Metal-semiconductor interface is a bottleneck for efficient transport of charge carriers through Transition Metal Dichalcogenide (TMD) based field-effect transistors (FETs). Injection of charge carriers across such interfaces is mostly limited by Schottky barrier at the contacts which must be reduced to achieve highly efficient contacts for carrier injection into the channel. Here we introduce a universal approach involving dry chemistry to enhance atomic orbital interaction between various TMDs (MoS2, WS2, MoSe2 and WSe2) & metal contacts has been experimentally demonstrated. Quantum chemistry between TMDs, Chalcogens and metals has been explored using detailed atomistic (DFT & NEGF) simulations, which is then verified using Raman, PL and XPS investigations. Atomistic investigations revealed lower contact resistance due to enhanced orbital interaction and unique physics of charge sharing between constituent atoms in TMDs with introduced Chalcogen atoms which is subsequently validated through experiments. Besides contact engineering, which lowered contact resistance by 72, 86, 1.8, 13 times in MoS2, WS2, MoSe2 and WSe2 respectively, a novel approach to cure / passivate dangling bonds present at the 2D TMD channel surface has been demonstrated. While the contact engineering improved the ON-state performance (ION, gm, mobility and RON) of 2D TMD FETs by orders of magnitude, Chalcogen based channel passivation was found to improve gate control (IOFF, SS, & VTH) significantly. This resulted in an overall performance boost. The engineered TMD FETs were shown to have performance on par with best reported till date

Legal Implication of Human and Physical- Activity Monitoring System Using Android Smartphone

ABSTRACT: The Project is, primarily, computer code that enables superintendent to watch their human quality portable. All incoming and outgoing calls, texts and multimedia system messages is seen and interrupted by the superintendent, United Nations agency will even monitor where their human area unit (through GPS), access a history of wherever they have been and created hold on if their human area unit going outside of geographical zones, area unit receiving texts from unapproved numbers or calls from illegal persons.That good phone-enabled dead reckoning supports correct however native coordinates of users' trajectories, whereas GPS provides world however inconsistent coordinates. Considering them at the same time, the project device techniques to refine the world positioning results by fitting the worldwide positions to the structure of domestically measured ones, therefore the refined positioning results area unit a lot of seemingly to elicit the bottom truth. The project develop a paradigm system, named GloCal conduct comprehensive experiments in each thronged urban and spacious residential area areas.Our aim is to develop associate economical and improved geographical quality following answer and conserve valuable mobile resources by dynamically adapting the pursuit theme by suggests that of context-aware customized route learning techniques. this technique uses golem based mostly mobile phones for the computer code to be run. The alerts are hold on within the centralized server just like the details of incoming call, text and multimedia messages and conjointly the timely location update of their human. Superintendent could later login into the centralized server and appearance at the most points of their employee mobile usag