Search results for "noble"
showing 10 items of 255 documents
Isolation of the CH3˙ rotor in a thermally stable inert matrix: first characterization of the gradual transition from classical to quantum behaviour …
2014
International audience; Matrix isolation is a method which plays a key role in isolating and characterizing highly reactive molecularradicals. However, the isolation matrices, usually composed of noble gases or small diamagnetic molecules,are stable only at very low temperatures, as they begin to desegregate even above a few tens of Kelvin.Here we report on the successful isolation of CH3 radicals in the cages of a nearly inert clathrate–SiO2matrix. This host is found to exhibit a comparable inertness with respect to that of most conventionalnoble gas matrices but it is characterized by a peculiar thermal stability. The latter property is related to thecovalent nature of the host material a…
Crustal controls on light noble gas isotope variability along the andean volcanic arc
2021
This study combines new noble gas data from fluid inclusions in minerals from Sabancaya, Ubinas, and El Misti (CVZ, Peru) and Villarica (South Chile, SVZ) with a revised noble gas compilation in the Andes, to identify systematic along arc variations in helium isotope compositions. We find 3He/4He ratios varying from 8.8 RA (Colombia) to 7.4 RA (Ecuador) within the NVZ, and only as high as 6.4 RA in the CVZ (RA is the atmospheric 3He/4He ratio of 1.39 × 10–6). These distinct isotope compositions cannot be explained by variable radiogenic 4He production via slab fluid transport of U and Th in the mantle wedge, since both NVZ and CVZ share similar slab sediment inputs (Th/La ≈ 0.08–0.13). Inst…
Ab Initio Simulation of Clusters: Relativistic Effects in Structure and Bonding of Noble Metal Nanoparticles
2005
Resolving the atomic and electronic structures of nanoclusters represents an important preliminary for their controlled use in future nanotechnologies. Here we show through the comparison of density-functional calculations with high-resolution photoelectron spectroscopy that 1.4 nm nanoparticles of silver (negatively charged clusters of 53 to 58 atoms) are icosahedral-based structures displaying a perfect icosahedral-induced electronic shell structure for Ag 55 − and slightly perturbed shell structures for the neighboring cluster sizes. At variance, 55-atom gold clusters exhibit several isomeric structures of low symmetry, with a largely diminished electronic shell structure. This surprisin…
Effects of Argon-Based and Nitrogen-Based Modified Atmosphere Packaging Technology on the Quality of Pomegranate (Punica granatum L. cv. Wonderful) A…
2021
Ready-to-eat pomegranate arils are considered a “functional food” for their health benefits and have desirable sensory characteristics, which have caused an increasing interest by the consumers for this product. The preparation process of ready-to-eat fruit products can cause severe injuries and worsen their quality and shelf life significantly. Modified atmosphere packaging (MAP) has been used broadly in the last years to maintain the quality of processed fruits and showed optimal results, in spite of the possible problems caused by the depletion of O2 and corresponding accumulation of CO2 in the package. This study was conducted to evaluate the effects of different MAP treatments, based o…
Noble Gases Investigation on Etnean Volcanic Gases and on the Erupted Products During the 2001-2006 Period
2008
Data acquired during the last 20 years of geochemical monitoring of volcanic gases lead us to better understand how volcanoes work. According to theoretical and experimental investigations, both the chemical and isotopic changes in sampled volcanic gases have been interpreted in terms of magma ascent using the models proposed by Nuccio & Paonita, (2001) and Caracausi et al. (2003). On the basis of numerical simulations of volatile degassing, we have been able to recognize episodes of magma migration from deeper reservoirs of Mount Etna to the shallower storage volume, until magma is erupted. The 3He/4He isotope ratios of gas emitted at the periphery of Mount Etna volcanic edifice exhibit sy…
Los desposorios del gobernador don Francisco de Castellví (1604-1672). Estrategia matrimonial y problemática dotal
2010
Este artículo estudia las circunstancias que acompañaron a las sucesivas nupcias del gobernador don Basilio de Castellví con las hijas del regente del Consejo de Aragón don Francisco de Castellví, de los condes de Carlet y de los marqueses de Villasor. Incide en una estrategia matrimonial que participa de la consanguinidad como fortalecimiento de los vínculos en el seno del linaje y de la promoción social mediante el entronque con destacadas casas nobiliarias, así como en el protagonismo adquirido por la cuestión hereditaria derivada del fallecimiento de las dos primeras esposas sin descendencia y por la restitución de la dote. (A)
La construction humaine d'un site sur le temps long : les climats du vignoble de Bourgogne
2012
Le site des climats du vignoble de Bourgogne est une oeuvre humaine, le résultat des transformations d'un milieu de culture par des sociétés qui se sont succédées sur plus de deux millénaires et qui ont marqué leur territoire de faon pérenne et durable. Produits de la volonté opiniâtre de développer un vignoble sur des pentes peu fertiles et d'acteurs multiples aux intérêts parfois contradictoires, les climats représentent une longue construction humaine où se situe sans doute toute leur valeur
Representations of American Indians and the Irish in educational reports, 1850s–1920s
2002
Modern colonialism, writes Gyan Prakash, ‘instituted enduring hierarchies of subjects and knowledges — the colonizer and the colonized, the Occidental and the Oriental, the civilized and the primitive, the scientific and the superstitious, the developed and the underdeveloped’. Such dichotomies ‘reduced complex differences and interactions to the binary (self/other) logic of colonial power’, and colonial rulers ‘constituted the “native” as their inverse image’. Such perceptions of difference as ‘other’ expressed what ‘civilized’ Westerners believed themselves not to be — but also what they feared they might become, should they lose rational self-control. The ‘other’, writes Eva Kornfelt, ‘t…
Income and expenses of Jan Karol Chodkiewicz (1686–1712), starost of Veliuona, Zabłudów, Baisogala and Daugeliskis, relating to his schooling in Wars…
2021
Postać Jana Karola Chodkiewicza (1686–1712) z linii supraskiej nie doczekała się do tej pory swojego opracowania choćby w postaci noty biograficznej. Artykuł niniejszy przybliża więc wybrany fragment z życiorysu wyżej wymienionego bohatera, który w latach 1700–1705 przebywał na naukach w szkole jezuickiej w Warszawie. Okres nauk stanowił ważne wydarzenie w życiu młodych magnatów, którzy w ich ramach przygotowywali się do służby państwowej i funkcjonowania w społeczeństwie szlacheckim. Nie inaczej było w przypadku Jana Karola, dziedzica ogromnej fortuny chodkiewiczowskiej, który resztę swojego krótkiego życia spędził później na sporach o dobra ojczyste. Młody starosta pobierał nauki w trudny…
Nobleza y expansión militar de la Corona de Aragón: La nobleza valenciana en las guerras del rey (1420-1448)
2003
This article studies the role of the nobility in the XV century military expansion of the Crown of Aragon, through the particular case of the valencian nobility and the Alphonse V the Magnanimous's war cycle betwen the years 1420 and 1448. If s first analyzed the development of the royal campaigns. Then, the Valencian lineages are identified, also precising their particular degree of involvement in the royal wars. The study is based upon the registers of the Royal Treasury and Cancillery, supplemented by notarial and judicial records, and the chronicles. The militarization of the nobility was unequal. The majority of the noblemen were involved occasionally in the royal wars, more as an soci…