Search results for "Deute"

Detection of deuterated molecules, but not of lithium hydride, in the z = 0.89 absorber toward PKS 1830−211

2020

Deuterium and lithium are light elements of high cosmological and astrophysical importance. In this work we report the first detection of deuterated molecules and a search for lithium hydride, 7LiH, at redshift z=0.89 in the spiral galaxy intercepting the line of sight to the quasar PKS1830-211. We used ALMA to observe several submillimeter lines of ND, NH2D, and HDO, and their related isotopomers NH2, NH3, and H2^18O, in absorption against the southwest image of the quasar, allowing us to derive XD/XH abundance ratios. The absorption spectra mainly consist of two distinct narrow velocity components for which we find remarkable differences. One velocity component shows XD/XH abundances that…

Insights into the decomposition pathway of a lutetium alkylamido complex via intramolecular C–H bond activation

2017

Abstract Synthesis, characterization and reaction chemistry of lutetium alkylamido LLu(CH2SiMe3)(NHCPh3) (2), L = 2,5-[Ph2P=N(4-iPrC6H4)]2N(C4H2)–, is reported. Complex 2 undergoes cyclometalation of the NHCPh3 ligand at elevated temperatures to produce the orthometalated complex LLu(κ2−N,C-(NHCPh2(C6H4))) (3) which converts to 0.5 equivalents of bis(amido) LLu(NHCPh3)2 (4) upon heating at 80 °C for 24 h. Reaction of complex 2 with 4-dimethylaminopyridine (DMAP) does not promote alkane elimination nor imido formation. A kinetic analysis of the thermal decomposition of complex 2, supported by deuterium labelling studies and computational analysis (PBE0/def2-TZVP/SDD(Lu)), indicate direct Csp…

Exceptionally preserved soft parts in fossils from the Lower Ordovician of Morocco clarify stylophoran affinities within basal deuterostomes.

2019

10 pages; International audience; The extinct echinoderm clade Stylophora consists of some of the strangest known deuterostomes. Stylophorans are known from complete, fully articulated skeletal remains from the middle Cambrian to the Pennsylvanian, but remain difficult to interpret. Their bizarre morphology, with a single appendage extending from a main body, has spawned vigorous debate over the phylogenetic significance of stylophorans, which were long considered modified but bona fide echinoderms with a feeding appendage. More recent interpretation of this appendage as a posterior “tail-like” structure has literally turned the animal back to front, leading to consideration of stylophorans…

H-2, H-3(+) and the age of molecular clouds and prestellar cores

2012

Measuring the age of molecular clouds and prestellar cores is a difficult task that has not yet been successfully accomplished although the information is of paramount importance to help in understanding and discriminating between different formation scenarios. Most chemical clocks suffer from unknown initial conditions and are therefore difficult to use. We propose a new approach based on a subset of deuterium chemistry that takes place in the gas phase and for which initial conditions are relatively well known. It relies primarily on the conversion of H 3 + into H 2D + to initiate deuterium enrichment of the molecular gas. This conversion is controlled by the ortho/para ratio of H2 that i…

Lagrangian simulations of stable isotopes in water vapor: An evaluation of nonequilibrium fractionation in the Craig-Gordon model

2009

[1] The Craig-Gordon model is the basis for the parameterization of water isotope fractionation during evaporation from the ocean in many atmospheric isotope models. Its exact formulation (e.g., with respect to the nonequilibrium fractionation factor k) is mainly based on theoretical considerations and not very well constrained by observations. This study addresses this issue by combining a recently developed Lagrangian moisture source analysis with a Craig-Gordon fractionation parameterization for the identified evaporation events in order to model isotope ratios in water vapor. This technique is applied to 45 measurement days of isotopes in water vapor at Rehovot (Israel) during the years…

Isotopic Effect on the Kinetics of the Belousov-Zhabotinsky Reaction

2007

In this work we present results about the deuterium isotope effect on the global kinetics of a Belousov-Zhabotinsky reaction in batch conditions. A nonlinear dependence of the Induction Period upon the percentage of deuterated reactants was found. The isotopic effect on the bromination reaction of malonic acid was evaluated.

New Measurements of the Beam Normal Spin Asymmetries at Large Backward Angles with Hydrogen and Deuterium Targets

2017

International audience; New measurements of the beam normal single spin asymmetry in the electron elastic and quasielastic scattering on the proton and deuteron, respectively, at large backward angles and at ⟨Q2⟩=0.22  (GeV/c)2 and ⟨Q2⟩=0.35  ( GeV/c)2 are reported. The experimentally observed asymmetries are compared with the theoretical calculation of Pasquini and Vanderhaeghen [Phys. Rev. C 70, 045206 (2004).PRVCAN0556-281310.1103/PhysRevC.70.045206]. The agreement of the measurements with the theoretical calculations shows a dominance of the inelastic intermediate excited states of the nucleon, πN and the Δ resonance. The measurements explore a new, important parameter region of the exc…

Bíblia. Nombres. Llatí

Ms. il·luminat Títol donat pel catalogador Col·lació: Vitel·la, f. i (pergamí actual) i (paper) + 239 + i (paper) i (pergamí actual) ; numeració moderna a llapis Composició: Text de la Bíblia i dels comentaris en dues o tres columnes i alguns fulls a línia tirada, nombre de línies variable ; pautat amb mina de plom Escriptura: Gòtica textual cal·ligràfica Decoració: Caplletres miniades amb motius antropomòrfics i vegetals. Calderons, titolets i majúscules alternant tintes de color blau i vermell Enquadernació: Restaurada, plateresca, pell verda sobre fusta, amb ferros freds. Al centre, amb ferros daurats, l'escut d'armes del duc de Calàbria entre florons; hi manquen els fermalls originals. …

Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering

2017

A semi-inclusive measurement of charged hadron multiplicities in deep inelastic muon scattering off an isoscalar target was performed using data collected by the COMPASS Collaboration at CERN. The following kinematic domain is covered by the data: photon virtuality $Q^{2}>1$ (GeV/$c$)$^2$, invariant mass of the hadronic system $W > 5$ GeV/$c^2$, Bjorken scaling variable in the range $0.003 < x < 0.4$, fraction of the virtual photon energy carried by the hadron in the range $0.2 < z < 0.8$, square of the hadron transverse momentum with respect to the virtual photon direction in the range 0.02 (GeV/$c)^2 < P_{\rm{hT}}^{2} < 3$ (GeV/$c$)$^2$. The multiplicities are pres…

Observations of molecular hydrogen (H2) mixing ratio and stable isotopic composition (deuterium content) at the Cabauw tall tower in the Netherlands

2016

This zip file contains the final corrected data that were used for the journal article "Observations of molecular hydrogen mixing ratio and stable isotopic composition at the Cabauw tall tower in the Netherlands" by Batenburg et al., Atmospheric Environment, 2016, doi:10.1016/j.atmosenv.2016.09.058   Please cite the original AtmosEnv article when using these data. The paper also contains more information about how these data were collected and calibrated, and on how the quality control flags were assigned. All samples were collected at the Cabauw tower, at the CESAR site (51.971° N, 4.927° E, http://www.cesar-observatory.nl/). H2 and deltaD(H2) are calibrated using one to four laboratory re…