Search results for "EXPANSION"
showing 10 items of 630 documents
Thermal expansion and magnetic properties of benzoquinone-bridged dinuclear rare-earth complexes.
2017
The synthesis and structural characterization of two benzoquinone-bridged dinuclear rare-earth complexes [BQ(MCl2·THF3)2] (BQ = 2,5-bisoxide-1,4-benzoquinone; M = Y (1), Dy (2)) are described. Of these reported metal complexes, the dysprosium analogue 2 is the first discrete bridged dinuclear lanthanide complex in which both metal centres reside in pentagonal bipyramidal environments. Interestingly, both complexes undergo significant thermal expansion upon heating from 120 K to 293 K as illustrated by single-crystal X-ray and powder diffraction experiments. AC magnetic susceptibility measurements reveal that 2 does not show the slow relation of magnetization in zero dc field. The absent of …
Bimodal velocity distribution of atoms released from nanosecond ultraviolet laser ablation
2005
We have investigated the velocity distributions of atoms released from a metallic gadolinium surface by UV laser ablation. The fluences of the nanosecond laser pulses were chosen for a pure release of neutrals and at a higher fluence level for the release of both neutrals and ions. In both cases a thermal Maxwell-Boltzmann slope has been observed for the low velocities, whereas for high velocities strong deviations from a thermal distribution have been seen. The observed velocity distribution has been explained by a bimodal structure including a thermal phase and a shockwave driven ``blow-off'' phase.
Pots and places in the Late Chalcolithic period. A view from the Eastern Ḫabur Region
2019
This paper attempts to contextualise the preliminary results of a survey (EHAS) and excavation (KUGAMID) projects recently undertaken by a team of the University of Tübingen in the uppermost region of Iraqi Kurdistan as far as the Late Chalcolithic period is concerned. Settlement patterns and land use, stratigraphic sequences and pottery assemblages are considered here in order to shed light on the dynamics of the emergence of social complexity and the establishment of proto-urban trajectories along the river banks, riverine plains, foothills and mountain valleys of the foothills of Zagros. Preliminary results suggest that the process of urbanisation in this area seems to be connected with …
Iterative approach to the exponential representation of the time–displacement operator
2005
An iterative method due to Voslamber is reconsidered. It provides successive approximations for the logarithm of the time–displacement operator in quantum mechanics. The procedure may be interpreted, a posteriori, as an infinite re-summation of terms in the so-called Magnus expansion. A recursive generator for higher terms is obtained. From two illustrative examples, a detailed comparative study is carried out between the results of the iterative method and those of the Magnus expansion.
Pig domestication and human-mediated dispersal in western Eurasia revealed through ancient DNA and geometric morphometrics.
2013
Zooarcheological evidence suggests that pigs were domesticated in Southwest Asia ∼8,500 BC. They then spread across the Middle and Near East and westward into Europe alongside early agriculturalists. European pigs were either domesticated independently or more likely appeared so as a result of admixture between introduced pigs and European wild boar. As a result, European wild boar mtDNA lineages replaced Near Eastern/Anatolian mtDNA signatures in Europe and subsequently replaced indigenous domestic pig lineages in Anatolia. The specific details of these processes, however, remain unknown. To address questions related to early pig domestication, dispersal, and turnover in the Near East, we …
The Impact of Credit on Economic Growth in the Global Crisis Context
2013
Abstract Is there a connection between credit and economic growth in the present economic context? Credit was one of the factors which triggered the global crisis, thus, in the present paper we attempt to show whether there is a connection between credit and economic growth, the economy being unable to develop in the absence of credit. With the aid of a statistic software we have tried to determine the supposed existence of a connection between the GDP, credits offered to public administration and credits offered to households. The results of the analysis show that credits offered to households contribute to a greater extent to the formation of the GDP than credits offered to public adminis…
Income inequality, fiscal stimuli and political (in)stability
2016
Using data for a large panel of countries, this paper investigates the role played by income inequality and fiscal stimuli episodes in shaping the likelihood of political stability. By means of Tobit estimations, we show that a rise in inequality increases the probability of government crises. However, such adverse distributional effect is reduced when expansionary or increasingly expansionary fiscal stimuli episodes or successful fiscal stimuli programs are put in place.
Rich regions, poor regions and bank branch deregulation in Spain
2016
Rich regions, poor regions and bank branch deregulation in Spain. Regional Studies. The links between financial deregulation and economic performance are evaluated in a European context. Specifically, the study analyses the relaxation of bank branching restrictions in Spain, which triggered a remarkable interregional expansion of savings banks that coincided with an unprecedented period of sustained economic expansion. Although related questions have been widely investigated for the United States, experiences in Europe have received far less research attention. An additional contribution of the paper lies in its use of quantile regression, which enables the investigation of the possibility …
Stimuli-responsive hybrid materials: breathing in magnetic layered double hydroxides induced by a thermoresponsive molecule
2014
[EN] A hybrid magnetic multilayer material of micrometric size, with highly crystalline hexagonal crystals consisting of CoAl-LDH ferromagnetic layers intercalated with thermoresponsive 4-(4-anilinophenylazo)benzenesulfonate (AO5) molecules diluted (ratio 9 : 1) with a flexible sodium dodecylsulphate (SDS) surfactant has been obtained. The resulting material exhibits thermochromism attributable to the isomerization between the azo (prevalent at room temperature) and the hydrazone (favoured at higher temperatures) tautomers, leading to a thermomechanical response. In fact, these crystals exhibited thermally induced motion triggering remarkable changes in the crystal morphology and volume. In…
ATNX2 is not a regulatory gene in Italian amyotrophic lateral sclerosis patients with C9ORF72 GGGGCC expansion
2015
Abstract There are indications that both familial amyotrophic lateral sclerosis (ALS) and sporadic ALS phenotype and prognosis are partly regulated by genetic and environmental factors, supporting the theory that ALS is a multifactorial disease. The aim of this article was to assess the role of ATXN2 intermediate length repeats in a large series of Italian and Sardinian ALS patients and controls carrying a pathogenetic C9ORF72 GGGGCC hexanucleotide repeat. A total of 1972 ALS cases were identified through the database of the Italian ALS Genetic consortium, a collaborative effort including 18 ALS centers throughout Italy. The study population included: (1) 276 Italian and 57 Sardinian ALS ca…