1,016 research outputs found
Performance analysis of an interacting quantum dot thermoelectric system
We analyze the nanocaloritronic performance of an interacting quantum dot
that is subject to an applied bias and an applied temperature gradient. It is
now well known that, in the absence of phonon contribution, a weakly coupled
non-interacting quantum dot can operate at thermoelectric efficiencies
approaching the Carnot limit. However, it has also been recently pointed out
that such peak efficiencies can only be achieved when operated in the
reversible limit, with a vanishing current and hence a vanishing power output.
In this paper, we point out three fundamental results affecting the
thermoelectric performance due to the inclusion of Coulomb interactions: a) The
reversible operating point carries zero efficiency, b) operation at finite
power output is possible even at peak efficiencies approaching the Carnot
value, and c) the evaluated trends of the the maximum efficiency deviate
considerably from the conventional {\it{figure of merit}} based result.
Finally, we also analyze our system for thermoelectric operation at maximum
power output.Comment: 10 pages, 6 figures, Resubmission- to be published in Phys. Rev.
Methyl 3-(4-fluorophenyl)-1-methyl-1,2,3,3a,4,9b-hexahydrochromeno[4,3-b]pyrrole-3a-carboxylate
In the title compound, C20H20FNO3, the pyrrolidine and benzopyran rings adopt half chair and twisted half chair conformations, respectively. The carboxylate group is almost perpendicular to the pyran ring [89.4 (1)°]
3-(2-Methylbenzylidene)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one
In the crystal structure of the title compound, C17H15NOS, the molecules form centrosymmetric dimers through pairs of N—H⋯O hydrogen bonds. The seven-membered ring adopts a distorted half-chair conformation
An account on light-fishing for the Carangid
The article reports on an accidental adoption of light fishing for the Carangid, Selar crumenophthalmus at Trivandrum coast of Kerala. Fishes enticed by the light to the surface were caught by employing the type of hooks and line known locally as 'achil'. A modest estimate of these catches during the fortnight goes well beyond 2,000 tonnes
3-Acetyl-4-hydroxyphenyl acrylate
In the title compound, C12H12O4, the hydroxy O and the C and O atoms of the acetyl group are almost coplanar [maximum deviation = 0.0356 (1) Å] with the benzene ring. The dihedral angle between the benzene ring and the plane through the non-H atoms of the methacryloyloxy group is 86.1 (1)°. In the crystal structure, molecules are linked by two C—H⋯O hydrogen bonds, forming dimers with graph-set descriptor R
2
2(16). A strong intramolecular O—H⋯O hydrogen bond is also observed
A study on virulence factors and antimicrobial resistance pattern among enterococci isolated from various clinical specimens from a tertiary care hospital
Background: Enterococci, adult faeces commensal are important nosocomial pathogens. E. faecalis is the most common cause of infection, followed by E. faecium. In the past two decades, they have developed resistance to many commonly used antimicrobial agents. Understanding virulence factors and monitoring antimicrobial resistance among Enterococci is essential for controlling the spread of bacterial resistance and important for epidemiological surveillance within the hospital environment. The aim of the study is to evaluate antibiotic resistance and virulence factors exhibited by Enterococcus sp.Methods: One hundred consecutive isolates of Enterococci isolated from different clinical samples of patients attending AVMC and H, a tertiary care center at Pondicherry in a period of 20 months were included in the study. Enterococcus sp were identified as per standard conventional bacteriologic methods and detected for the production of virulence factors such as Hemolysin production, Gelatinase production. Antimicrobial susceptibility testing was carried out by disc diffusion method and MIC of vancomycin and teicoplanin was determined by E-test strips.Results: Among 100 Enterococcal isolates included in the study, 81% were E. faecalis and 19% were E. faecium which were isolated from urine (44%), Pus (51%) and others specimen (5%, which includes blood 80% and drain tube 20%). In this study, overall 15% of E. faecalis and 1% of E. faecium showed hemolysin production and Gelatinase was produced by 6% of E. faecalis and 4% of E. faecium. Majority of E. faecalis and E. faecium strains isolated in our study, had increased sensitivity were to be exhibited for Linezolid, Vancomycin followed by high level gentamycin and high degree of resistance to penicillin, ciprofloxacin and cotrimoxazole. Analyzing the results of MIC of vancomycin and teicoplanin, 5 isolates were classified phenotypically as VanB phenotype that possess only moderate to high levels of vancomycin resistance and one isolate obtained from drain tube which showed MIC of vancomycin as 120µg/ml and teicoplanin 16µg/ml was grouped into VanA.Conclusions: Though the prevalence of vancomycin resistant Enterococcci (VRE) is very low in our study, yet regular monitoring of vancomycin resistance is very crucial for early detection, treatment, application of preventive and control measures and most importantly to check the spread of virulent multidrug resistant Enterococcus species
Mixed-Mode Electro-Optical Operation of Ge2Sb2Te5 Nanoscale Crossbar Devices
This is the author accepted manuscript. The final version is freely available from Wiley via the DOI in this record.The use of phase-change materials for a range of exciting new optoelectronic applications from artificial retinas to ultrahigh-resolution displays requires a thorough understanding of how these materials perform under a combination of optical and electrical stimuli. This study reports for the first time the complex link between the electronic and optical properties in real-world crossbar nanoscale devices constructed by confining a thin layer of Ge2Sb2Te5 between transparent indium tin oxide electrodes, forming an optical nanocavity. A novel proof-of-concept device that can be operated by a combination of optical and electrical stimuli is presented, leading the way for the development of further applications based on mixed-mode electro-optical operation.CONACYT. Grant Number: 215365. EPSRC. Grant Numbers: EP/J018783/1, EP/M015173/1, EP/M015130/1, EP/J018694/
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