Search results for "ample"
showing 10 items of 2398 documents
La Valle dei Templi in epoca medioevale. Caratterizzazione antropologica e paleopatologica delle sepolture antistanti in Tempio della Concordia
2021
Riassunto ― Il lavoro presenta i risultati delle analisi bio-archeologiche effettuate su resti scheletrici umani rinvenuti in quattordici sepolture di epoca medioevale rinvenute nel Parco Archeologico della Valle dei Templi di Agrigento (Sicilia). L’obiettivo è stato l’acquisizione delle informazioni necessarie per la ricostruzione del profilo biologico di ciascun individuo, al fine di determinarne il sesso, la stima dell’età biologica alla morte, la stima della statura e la valutazione delle patologie e degli indicatori di stress occupazionale mediante le correnti metodologie e tecniche diagnostiche di tipo antropologico. Sebbene il cattivo stato di conservazione di alcuni individui non ne…
Depinning frequency in a heavily neutron-irradiated MgB2 sample
2008
The magnetic-field-induced variations of the microwave surface resistance have been investigated in a heavily neutron-irradiated MgB2 sample, in which the irradiation has caused the merging of the two gaps into a single value. The experimental results have been analyzed in the framework of the Coffey and Clem model. By fitting the experimental data, we have determined the field dependence of the depinning frequency, omega_0, at different values of the temperature. Although the pinning is not particularly effective, the value of omega_0 obtained at low temperatures is considerably higher than that observed in conventional low-temperature superconductors.
Anomalous magnetic hysteresis in the microwave surface resistance of MgB2 superconductor
2007
We report experimental results of the field-induced variations of the microwave surface resistance in samples of MgB2, produced by different methods. By sweeping the DC magnetic field at increasing and decreasing values, we have detected a magnetic hysteresis that can be ascribed to the different magnetic induction, due to the critical state of the fluxon lattice. The hysteresis observed in the bulk samples has an unusual shape, which cannot be justified in the framework of the critical-state models.
Effects of Weak Links in the Nonlinear Microwave Response of MgB2 Superconductor
2006
We report experimental results of second-harmonic (SH) response at microwave frequency in several ceramic MgB2 samples, prepared by different methods. The SH signal has been investigated as a function of the temperature and DC magnetic field. The investigation has been carried out at low magnetic fields, where nonlinear processes arising from motion of Abrikosov fluxons are ineffective. We show that the low-temperature SH emission is ascribable to processes involving weak links. Comparison among the peculiarities of the SH signal radiated by the different samples shows that the presence of weak links strongly depends on the sample preparation method, as well as the purity and morphology of …
Standardisation, Reference Materials and Comparative Measurements for Surface Area and Pore Characterisation
1991
Summary This paper reviews current activities to standardise measuring procedures for surface area and pore size determination. Comparative measurements at different laboratories using candidate reference materials revealed that surfaces of highly dispersed materials can be affected remarkably during storing and sample preparation. On account of the fractal nature of these materials, the results depend on the measuring methods. Reference materials of dispersed materials are offered by national and international standardisation administrations and by industrial distributers. The standardisation of measuring methods becomes more and more international (ISO, IUPAC). The survey includes tables …
A Successive Umbrella Sampling Algorithm to Sample and Overcome Free Energy Barriers
2006
AN EMPIRICAL STUDY OF LATVIAN CONSUMER’S ATTITUDES AND PERCEPTIONS TOWARDS GENETICALLY MODIFIED ORGANISMS
2016
Genetic modification and genetically modified organisms (GMO) remains a controversial issue. Latvian consumers’ attitude towards genetic modification and GMO have been characterized as negative using Eurobarometer data, but so far no specific investigation of Latvian consumers has been done in this field. The aim of this study was to analyse Latvian consumers’ attitude towards genetic modification and GMO, the subjective and objective knowledge about this questions and acceptability of use of GMO in different application areas. Main task in frame of this research is to summarize different literature and data available to outline some of factors that influence attitudes towards GMO: mainly p…
Do board characteristics affect environmental performance? A study of EU firms
2019
This paper explores the relationship between board characteristics and environmental performance. We adopt a triple perspective of environmental performance, focussing on emissions (waste and CO2), resource consumption (water and energy), and the implementation of environmental initiatives. The sample comprises 644 nonfinancial European Union–based companies. The data cover the period 2002 to 2017. The results confirm that gender diversity and the existence of a corporate social responsibility committee are positively associated with the firms' environmental performance. This finding is consistent with the view that the educational background, talent, and experience of women help promote su…
Properties of Swift's intermediate bursts
2011
Based on their prompt, high-energy emission, gamma-ray bursts are usually classified into short-duration and long-duration classes. A third intermediate group has been identified on statistical grounds but its individual properties have not yet been studied in detail. Using the large sample of follow-up observations of GRBs produced during the Swift era we analyze the individual characteristics of this group. We find that intermediate bursts are significantly different from short GRBs but share many properties with long bursts, probably pointing to a common progenitor type. However, we find that intermediate bursts are significantly dimmer and have on average lower redshifts. Based on their…
The generalized H-point standard-additions method to determine analytes present in two different chemical forms in unknown matrix samples. Part I. Ge…
2000
This paper shows how the generalized H-point standard-additions method (GHPSAM) can be used to obtain the total concentration or concentrations of different chemical forms of an analyte when the matrix of the sample is completely unknown. The spectral regions where the interferent behaviour can be considered as linear are found and the analyte concentration free from bias error is estimated. This paper includes the already published features of the GHPSAM and a new modification of this method which allows the simultaneous determination of two chemical forms of an analyte in a sample.