Search results for "COPI"
showing 10 items of 2618 documents
Niobium Nitride Thin Films for Very Low Temperature Resistive Thermometry
2019
We investigate thin film resistive thermometry based on metal-to-insulator-transition (niobium nitride) materials down to very low temperature. The variation of the NbN thermometer resistance have been calibrated versus temperature and magnetic field. High sensitivity in tempertaure variation detection is demonstrated through efficient temperature coefficient of resistance. The nitrogen content of the niobium nitride thin films can be tuned to adjust the optimal working temperature range. In the present experiment, we show the versatility of the NbN thin film technology through applications in very different low temperature use-cases. We demonstrate that thin film resistive thermometry can …
Pt(II) nitrile complexes: New insights on old complexes from a combined experimental and theoretical study
2017
Abstract The spectroscopic characterization of cis - and trans -[PtCl 2 (NCR) 2 ] (R = CH 3 , Ph, CH 2 Ph) was reported in solid state and solution phase. Moreover, the X-ray structures of cis -[PtCl 2 (NCCH 3 ) 2 ], cis - and trans -[PtCl 2 (NCPh) 2 ] were redetermined at low temperature. FT-IR and NMR showed a blue-shift and a slight shielding of the νCN and δ ( 13 C CN ) values, respectively, in a counterintuitive way with respect to the well known improved reactivity towards nucleophiles of nitriles ligands coordinated to platinum(II), when compared to their free forms. These spectroscopic behaviors were also confirmed by theoretical experiments at DFT level. Moreover, DFT approach show…
Conceptual and epistemological difficulties of future teachers of physics and chemistry in the energetic explanations of physical and chemical phenom…
2016
En este trabajo analizamos las dificultades conceptuales y epistemológicas que tienen sobre termoquímica estudiantes universitarios de los últimos cursos de Física, Química e Ingeniería Química. Para ello se han aplicado a una muestra de 35 de estos futuros profesores dos cuestionarios sobre efectos térmicos en fenómenos físicos y químicos que han de explicar y se han categorizado sus respuestas según los razonamientos usados. Se ha constatado que la mayoría de los estudiantes no saben delimitar en el nivel macroscópico los sistemas que interaccionan, no utilizan el concepto de energía interna ni la primera ley de la termodinámica en los procesos físicos y químicos. Muy pocos de estos profe…
A Method for Accurate Measurements of Optimum Noise Parameters of Microwave Transistors
1985
A method for measuring losses of the tuner network used as noise source admittance transformer in transistor noise parameter test-set is presented. Since the method is based on noise figure measurements, tuner losses can be determined on-line while performing measurements for determining transistor noise parameters. As experimental verifications the optimum noise parameters of a GaAs FET in the 4 - 12 GHz frequency range, measured through a computer-assisted measuring system, are reported.
ACCURATE MEASUREMENTS OF OPTIMUM NOISE PARAMETERS OF MICROWAVE TRANSISTORS
1986
A method for measuring losses of the tuner network used as noise source admittance transformer in transistor noise parameter test-set is presented. Since the method is based on noise figure measurements, tuner losses can be determined on-line while performing measurements for determining transistor noise parameters. As experimental verifications the optimum noise parameters of a GaAs FET in the 4 - 12 GHz frequency range, measured through a computer-assisted measuring system, are reported.
Pratica clinica e aderenza a Linee Guida nella diagnosi e terapia delle neoplasie vescicali non muscolo-invasive: report di uno studio ricognitivo ba…
2015
Clinical practice and adherence to the diagnosis and treatment of NMIBC guidelines: a report of a recognition based clinical cases study For non-muscle invasive bladder cancer, a disease with a considerable epidemiological and socio-economic impact, the introduction of the Guidelines has always evoked as a tool for the resolution of long-standing disputes in terms of diagnosis and therapy. Check the degree of routine clinical practice adherence to the Recommendations is for this disease, more than for other uro-oncology pathology, an urgent need felt by the urological community. To assess the level of Guidelines adherence’s, and study issues related to the paths of diagnosis and treatment o…
P26 Early motherhood: a qualitative study exploring experiences of adolescent mothers in the hohoe municipality of ghana
2018
Background Each year between 14 and 15 million adolescent girls give birth, accounting for more than 10% of births globally. Motherhood is an exciting time for every woman and the society at large and also seen as a significant part of any woman’s identity but that is often not the case for the adolescent mother. Adolescent motherhood can be a time of mixed feelings as it occurs at a critical time of their lives. This study examined challenges adolescent mothers face during early motherhood and strategies to improve early motherhood for better social and health outcomes. Methods Based on a phenomenological perspective, this qualitative study was conducted in the Hohoe Municipality where pur…
Azimuthally-differential pion femtoscopy relative to the third harmonic event plane in Pb–Pb collisions at √sNN = 2.76 TeV
2018
Azimuthally-differential femtoscopic measurements, being sensitive to spatio-temporal characteristics of the source as well as to the collective velocity fields at freeze out, provide very important information on the nature and dynamics of the system evolution. While the HBT radii oscillations relative to the second harmonic event plane measured recently reflect mostly the spatial geometry of the source, model studies have shown that the HBT radii oscillations relative to the third harmonic event plane are predominantly defined by the velocity fields. In this Letter, we present the first results on azimuthally-differential pion femtoscopy relative to the third harmonic event plane as a fun…
Exciton-created defects and their participation in energy transfer from excitons to Tl ions in KI–Tl crystal
2000
Abstract Luminescence properties (spectra, yields, kinetics) of Tl ions induced by energy transfer from different types of anion excitons were studied and compared with those observed under direct Tl ion excitation by light quanta from A and C absorption bands in KI–Tl crystal at low temperature. The mechanism of energy transfer from excitons to the impurity ions was proposed based on the exciton-created defects participating in the impurity ion excitation.
Sizeable beta-strength in $^{31}$Ar (β3p) decay
2014
5 pags. ; 7 figs. ; Open Access funded by SCOAP3 - Sponsoring Consortium for Open Access Publishing in Particle Physics