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Abstract  

In this paper we introduce two key notions related to understanding the glassy state problem. One is the notion of the excitation profile for an amorphous system, and the other is the notion of the simple glassformer. The attributes of the latter may be used, in quite different ways, to calculate and characterize the former. The excitation profile itself directly reflects the combined phonon/configuron density of states, which in turn determines the liquid fragility. In effect, we are examining the equivalent, for liquids, of the low temperature Einstein-Debye regime for solids though, in the liquid heat capacity case, there is no equivalent of the Dulong/Pettit classical limit for solids.To quantify these notions we apply simple calorimetric methods in a novel manner. First we use DTA techniques to define some glass-forming systems that are molecularly simpler than any described before, including cases which are 80 mol% CS2, or 100% S2Cl2. We then use the same data to obtain the fragility of these simple systems by a new approach, the 'reduced glass transition width' method. This method will be justified using data on a wider variety of well characterized glassformers, for which the unambiguous F 1/2 fragility measures are available. We also describe a new DTA method for obtaining F 1/2 fragilities in a single scan. We draw surprising conclusions about the fragility of the simplest molecular glassformers, the mixed LJ glasses, which have been much studied by molecular dynamics computer simulation.These ideas are then applied to a different kind of simple glass — one whose thermodynamics is dominated by breaking and making of covalent bonds — for which case the excitation profile can be straight-forwardly modeled. Comparisons with the profile obtained from computer studies of the molecularly simple glasses are made, and the differences in profiles implied for strong vs. fragile systems are discussed. The origin of fragility in the relation between the vibrational and configurational densities of states is discussed, and the conditions under which high fragility can convert to a first order liquid-liquid transition, is outlined.

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Summary The ETS-10 is a newly formed titano-silicate the structure of which was resolved thanks to the XRD, EDS, HREM and mass NMR. The ETS-10 is a potentially good catalyst. The aim of this research is to study the physicochemical properties of ET(Zr)S-10 obtained from a gel containing different amounts of Zr. The analyses used are XRD, thermal analysis (TG-DSC), SEM, and 29Si NMR.

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Abstract  

The present paper reports the regioselective [15NO2]-labeling of N-methoxy-2,4,6-trinitroaniline and 2,2-diphenyl-1-picrylhydrazine (reduced DPPH). Starting from N-methoxy-2,6-dinitroaniline, or N-methoxy-2,4-dinitroaniline, nitration in methylene chloride with solid sodium [15N]nitrite and 15-crown-5-ether afforded N-methoxy-2,6-dinitro-4-[15N]nitroaniline and N-methoxy-2,4-dinitro-6[15N]nitroaniline, respectively. The same compounds could be prepared in higher purity by nitrodecarboxylation (ipso-substitution) under the same conditions starting from N-methoxy-4-carboxy-2,6-dinitroaniline (4-methoxyamino-3,5-dinitrobenzoic acid) and N-methoxy-2-carboxy-4,6-dinitroaniline (2-methoxyamino-3,5-dinitrobenzoic acid). Similarly,ipso-substitution of 2,2-diphenyl-1-(4-carboxy-2,6-dinitrophenyl)-hydrazine afforded, under the same reaction conditions, 2,2-diphenyl-1-(2,6-dinitro-4-[15N]nitrophenyl)-hydrazine. By1H-NMR and13C-NMR it was also observed that under these reaction conditions a14NO2 group can be replaced by a15NO2 group.

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Summary  

Vanadium-48 was produced with an activity of 222 MBq (6 mCi) by the natTi(d,xn)48V nuclear reactions in the U-120 cyclotron. The energy of the irradiating beam was 13 MeV, its intensity 5 μA, and the metallic Ti target dimension 11’11 mm2 (0.1 mm thickness). For target cooling, circulated water in target backside was used. After 3 cooling days, only 48V and some 46Sc (T 1/2 = 83.8 d), produced by the side nuclear reaction 48Ti(d,α)46Sc were found in the target. For production of the radiotracer of 48V and for the preparation of source for standardization of 48V by 4πβ-γ coincidence, the Ti target was dissolved either in HF or in H2SO4. For both dissolving methods an ion-exchange separation procedure was developed.

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This paper presents an analysis of the Arruda accessory pathway localization method for patients suffering from Wolff-Parkinson-White syndrome, with modifications to increase the overall accuracy. The Arruda method was tested on a total of 79 cases, and 91.1% localization performance was reached. After a deeper analysis of each decision point of the Arruda localization method, we considered that the lead aVF was not as relevant as other leads (I, II, III, V1) used. The branch of the decision tree, which evaluates the left ventricle positions, was entirely replaced using different decision criteria based on the same biological parameters. The modified algorithm significantly improves the localization accuracy in the left ventricle, reaching 94.9%. An accurate localization performance of non-invasive methods is relevant because it can enlighten the necessary invasive interventions, and it also reduces the discomfort caused to the patient.

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Journal of Thermal Analysis and Calorimetry
Authors:
Hermi F. Brito
,
Jukka Hassinen
,
Jorma Hölsä
,
Högne Jungner
,
Taneli Laamanen
,
Mika Lastusaari
,
Marja Malkamäki
,
Janne Niittykoski
,
Pavel Novák
, and
Lucas C. V. Rodrigues

Abstract

The details of the mechanism of persistent luminescence were probed by investigating the trap level structure of Sr2MgSi2O7:Eu2+,R3+ materials (R: Y, La-Lu, excluding Pm and Eu) with thermoluminescence (TL) measurements and Density Functional Theory (DFT) calculations. The TL results indicated that the shallowest traps for each Sr2MgSi2O7:Eu2+,R3+ material above room temperature were always ca. 0.7 eV corresponding to a strong TL maximum at ca. 90 °C. This main trap energy was only slightly modified by the different co-dopants, which, in contrast, had a significant effect on the depths of the deeper traps. The combined results of the trap level energies obtained from the experimental data and DFT calculations suggest that the main trap responsible for the persistent luminescence of the Sr2MgSi2O7:Eu2+,R3+ materials is created by charge compensation lattice defects, identified tentatively as oxygen vacancies, induced by the R3+ co-dopants.

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Acta Veterinaria Hungarica
Authors:
Baukje G. Andela
,
Frank J. C. M. Van Eerdenburg
,
Ali Choukeir
,
Dávid Buják
,
Zoltán Szelényi
,
Szabolcs Boldizsár
,
Fruzsina Luca Kézér
,
László Molnár
,
Levente Kovács
, and
Ottó Szenci

Activities of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, and concentrations of serum metabolites [beta-hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA)] of primiparous (n = 83) and multiparous (n = 213) Holstein cows were studied as possible predictors of retained fetal membranes (RFM), grade 2 clinical metritis (CM) and clinical endometritis (CEM). A logistic regression model was used to calculate odds ratios (OR) for the prevalence of CM diagnosed between 0–5, 6–10 and 11–20 days in milk (DIM) and for the prevalence of CEM diagnosed between 22–28 and 42–49 DIM. The activities of the examined serum enzymes did not show significant associations either with CM or with CEM. For NEFA sampled on days 0 and 5, an OR of 2.38 for CM 0–20 DIM and an OR of 2.58 for CM 11–20 DIM was found. For BHB sampled on days 0 and 5, an OR of 8.20 for CEM 22–28 and 42–49 DIM and an OR of 1.98 for CM 6–10 DIM were found. The prevalence of RFM was higher in ≥ 4 parity cows compared to primiparous cows (46.3% vs. 26.5%). BHB and NEFA levels measured between 0 and 5 DIM could have a predictive ability for postpartum uterine disorders such as RFM, CM and CEM.

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Acta Veterinaria Hungarica
Authors:
Renan B. Paiano
,
Fábio C. Lahr
,
Lucas S. B. Silva
,
Diego S. Marques
,
Catia A. Ferreira
,
Daniela B. Birgel
,
Rafael S. Bisinotto
, and
Eduardo H. Birgel Junior

The main aim of the current study was to assess the prevalence of anaemia in Holstein dairy cows during the puerperium, and the haematological and biochemical profile of dairy cows with and without anaemia. The study was conducted in seven dairy herds in São Paulo State, Brazil. The evaluated sample comprised a total of 336 Holstein cows. Blood samples were collected at postpartum day 25 ± 3. Haematological analysis included white blood cell, red blood cell and platelet count, haematocrit value, haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration. The biochemical profile encompassed cholesterol, non-esterified fatty acids, β-hydroxybutyrate, albumin, globulin, fibrinogen, calcium and total bilirubin concentrations. The prevalence of anaemia was 16.3% in all herds, and this was not affected by clinical diseases, milk production, parity and body score condition. Moreover, anaemic cows had lower red blood cell count, haematocrit, haemoglobin, serum cholesterol and calcium concentrations and higher white blood cell and platelet counts, mean corpuscular haemoglobin, red cell distribution width, non-esterified fatty acids, β-hydroxybutyrate, fibrinogen and globulin concentrations when compared with non-anaemic cows. The results indicate changes in energy balance and an inflammatory process in anaemic cows.

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Journal of Behavioral Addictions
Authors:
Charlotte Eben
,
Beáta Bőthe
,
Damien Brevers
,
Luke Clark
,
Joshua B. Grubbs
,
Robert Heirene
,
Anja Kräplin
,
Karol Lewczuk
,
Lucas Palmer
,
José C. Perales
,
Jan Peters
,
Ruth J. van Holst
, and
Joël Billieux

Abstract

Open science refers to a set of practices that aim to make scientific research more transparent, accessible, and reproducible, including pre-registration of study protocols, sharing of data and materials, the use of transparent research methods, and open access publishing. In this commentary, we describe and evaluate the current state of open science practices in behavioral addiction research. We highlight the specific value of open science practices for the field; discuss recent field-specific meta-scientific reviews that show the adoption of such practices remains in its infancy; address the challenges to engaging with open science; and make recommendations for how researchers, journals, and scientific institutions can work to overcome these challenges and promote high-quality, transparently reported behavioral addiction research. By collaboratively promoting open science practices, the field can create a more sustainable and productive research environment that benefits both the scientific community and society as a whole.

Open access