Search results for "Argon"

Pelargonium leaves as bioaccumulator of polynuclear aromatic hydrocarbons: Analysis and evaluation of sources and air quality in Palermo area

2006

The leaves of Pelargonium zonale have been chosen because this plant is widespread in both the Mediterranean metropolitan and peripheral areas. The paper describes the analytical method, and the results concerning the determination of PAHs in Pelargonium leaves collected in the Palermo area, and their possible origins. The GC-MS method was applied, since identification of all the different compounds with spectra libraries is possible. Samples were analyzed for 22 PAHs. The reported analytical method is complete within 2 hours, and more convenient than that of other researches. Total PAH concentrations in leaves varied between 24-357 g/kg d.w. The relative abundance of the analyzed PAHs can …

2021

FTIR spectroscopy was combined with the matrix isolation technique and quantum chemical calculations with the aim of studying complexes of isocyanic acid with sulfur dioxide. The structures of the HNCO⋯SO2 complexes of 1:1, 1:2 and 2:1 stoichiometry were optimized at the MP2, B3LYPD3, B2PLYPD3 levels of theory with the 6-311++G(3df,3pd) basis set. Five stable 1:1 HNCO⋯SO2 complexes were found. Three of them contain a weak N-H⋯O hydrogen bond, whereas two other structures are stabilized by van der Waals interactions. The analysis of the HNCO/SO2/Ar spectra after deposition indicates that mostly the 1:1 hydrogen-bonded complexes are present in argon matrices, with a small amount of the van de…

Readiness of the ATLAS liquid argon calorimeter for LHC collisions

2010

The ATLAS liquid argon calorimeter has been operating continuously since August 2006. At this time, only part of the calorimeter was readout, but since the beginning of 2008, all calorimeter cells have been connected to the ATLAS readout system in preparation for LHC collisions. This paper gives an overview of the liquid argon calorimeter performance measured in situ with random triggers, calibration data, cosmic muons, and LHC beam splash events. Results on the detector operation, timing perfor-mance, electronics noise, and gain stability are presented. High energy deposits from radiative cosmic muons and beam splash events allow to check the intrinsic constant term of the energy resolutio…

A 4 tonne demonstrator for large-scale dual-phase liquid argon time projection chambers

2018

A 10 kilo-tonne dual-phase liquid argon TPC is one of the detector options considered for the Deep Underground Neutrino Experiment (DUNE). The detector technology relies on amplification of the ionisation charge in ultra-pure argon vapour and offers several advantages compared to the traditional single-phase liquid argon TPCs. A 4.2 tonne dual-phase liquid argon TPC prototype, the largest of its kind, with an active volume of \three has been constructed and operated at CERN. In this paper we describe in detail the experimental setup and detector components as well as report on the operation experience. We also present the first results on the achieved charge amplification, prompt scintillat…

Line Identification of Atomic and Ionic Spectra of Holmium in the Near-UV. II. Spectra of Ho ii and Ho iii

2017

Fourier Transform spectra of holmium (Ho) in the UV spectral range from 31,530 to 25,000 cm−1 (317 to 400 nm) have been investigated, particularly focusing on the ionic lines. The distinction between the different degrees of ionization (I, II, and III) is based on differences in signal-to-noise ratios from two Ho spectra, which have been measured with different buffer gases, i.e., neon and argon. Based on 106 known Ho ii and 126 known Ho iii energy levels, 97 lines could be classified as transitions of singly ionized Ho and 9 lines could be classified as transitions of doubly ionized Ho. Of the 97 Ho ii lines, 6 have not been listed in the extant literature. Another 215 lines have been assi…

The Cotton-Mouton effect of Neon and Argon: a benchmark study using highly correlated coupled cluster wave functions

2004

The Cotton-Mouton effect (magnetic field induced linear birefringence) has been studied for neon and argon using state-of-the-art coupled cluster techniques. The coupled cluster singles, doubles and triples (CCSDT) approach has been used to obtain static benchmark results and the CC3 model with an approximate treatment of triple excitations to obtain frequency-dependent results. In the case of neon the effect of excitations beyond triples has also been estimated via coupled cluster calculations including quadruple excitations (CCSDTQ), pentuple excitations (CCSDTQP), etc. up to the full configuration-interaction level. The results obtained for the anisotropy of the hypermagnetizability Delt…

High-Resolution Jet-Cooled Spectroscopy of SF6: The ν2+ ν6Combination Band of32SF6and the ν3Band of the Rare Isotopomers

1998

The Fourier transform infrared spectrum of SF6 was recorded in a supersonic expansion jet of an SF6/argon mixture. The SF6:Ar seeding ratio was 2:3. The instrumental bandwidth was 0.005 cm-1. A globar source and an MCT detector were used. A rotational temperature of approximately 30 K was achieved. The nu2 + nu6 combination band of 32SF6 was analyzed using a modified version of the spherical top data system (STDS) programs developed in Dijon. A very good fit was obtained for this band with an rms of 0.0036 cm-1. The effective Hamiltonian was developed up to fourth order for the nu2 + nu6 part, to second order for the nu2 and ground state parts, and to first order for the nu6 part. Five hund…

Studies of Inelastic Scattering of Fast Heavy Ions

2003

In the present experiment 250A MeV O-17 ions were melastically scattered front xenon and argon in the cluster-jet target of the CELSIUS storage ring. The magnetic lattice of the ring is such that the quadrant following the target can be used as a magnetic spectrometer with an acceptance cone of +/-0.6degrees, centred at 0degrees. A focal plane telescope, placed in the injection straight section. determined the excitation energy of the residual target nuclei. Data were taken for excitation energies between 15 and 35 MeV. The neutron decay was studied by the EDEN detector array positioned around the target, covering an angular range of 7-110degrees. In order to investigate a previously observ…

The Cryogenic Pumping Section of the KATRIN Experiment

2010

In order to determine the absolute scale of the neutrino mass with a sensitivity of 0.2 (90% Confidence Level), the Karlsruhe Tritium Neutrino experiment (KATRIN) operates a series of superconducting magnet systems, which guide the electrons adiabatically from the source of tritium beta-decay to the detector within a magnetic flux of 191 . The 7 m long Cryogenic Pumping Section (CPS) is designed as the final barrier of tritium circulation. It has to reduce the tritium partial pressure below Pa in order to limit the background count rate in the measurement. To achieve this, the tritium entering the CPS must be adsorbed onto a pre-condensed argon layer on the inner surface of the beam tube at…

HIGH-RESOLUTION FOURIER TRANSFORM SPECTROSCOPY OF Nb i IN THE NEAR-INFRARED

2015

In this study, a Fourier Transform spectrum of Niobium (Nb) is investigated in the near-infrared spectral range from 6000 to 12,000 cm−1 (830–1660 nm). The Nb spectrum is produced using a hollow cathode discharge lamp in an argon atmosphere. Both Nb and Ar spectral lines are visible in the spectrum. A total of 110 spectral lines are assigned to the element Nb. Of these lines, 90 could be classified as transitions between known levels of atomic Nb. From these classified Nb i transitions, 27 have not been listed in literature previously. Additionally, 8 lines are classified for the first time.