Search results for " fluid"
showing 10 items of 3232 documents
Exosome levels in human body fluids: A tumor marker by themselves?
2016
Despite considerable research efforts, the finding of reliable tumor biomarkers remains challenging and unresolved. In recent years a novel diagnostic biomedical tool with high potential has been identified in extracellular nanovesicles or exosomes. They are released by the majority of the cells and contain detailed molecular information on the cell of origin including tumor hallmarks. Exosomes can be isolated from easy accessible body fluids, and most importantly, they can provide several biomarkers, with different levels of specificity. Recent clinical evidence shows that the levels of exosomes released into body fluids may themselves represent a predictive/diagnostic of tumors, discrimin…
Overview of the JET preparation for deuterium-tritium operation with the ITER like-wall
2019
Documento escrito por un elevado número de autores/as, sólo se referencia el/la que aparece en primer lugar y los/as autores/as pertenecientes a la UC3M For the past several years, the JET scientific programme (Pamela et al 2007 Fusion Eng. Des. 82 590) has been engaged in a multi-campaign effort, including experiments in D, H and T, leading up to 2020 and the first experiments with 50%/50% D–T mixtures since 1997 and the first ever D–T plasmas with the ITER mix of plasma-facing component materials. For this purpose, a concerted physics and technology programme was launched with a view to prepare the D–T campaign (DTE2). This paper addresses the key elements developed by the JET programme d…
Large numbers of cold positronium atoms created in laser-selected Rydberg states using resonant charge exchange
2016
Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs atoms to Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial with 30 million trapped positrons, more than 700 000 of the created Ps* have trajectories near the axis of the apparatus, and are detected using Stark ionization. This number of Ps* is 500 times higher than realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second charge exchange of these near-axis Ps* with trapped antiprotons could be used to produce cold antihydrogen, and this antihydrogen production is e…
Nuclear anapole moment interaction in BaF from relativistic coupled-cluster theory
2018
We present high accuracy relativistic coupled cluster calculations of the P-odd interaction coefficient $W_A$ describing the nuclear anapole moment effect on the molecular electronic structure. The molecule under study, BaF, is considered a promising candidate for the measurement of the nuclear anapole moment, and the preparation for the experiment is now underway [Altunas et al., Phys. Rev. Lett. 120, 142501 (2018)]. Influence of various computational parameters (size of the basis set, treatment of relativistic effects, and treatment of electron correlation) on the calculated $W_A$ coefficient is investigated and a recommended value of 147.7 Hz with an estimated uncertainty of 1.5% is prop…
Utilization of impedance spectroscopy to investigate the self-assembly behavior of amphiphiles soluble in supercritical carbon dioxide: Preliminary r…
2007
Abstract A mixture of CO 2 , water, methyl orange (MO) and Dynol 604 surfactant was analyzed at 309 K and 20 MPa simultaneously by impedance and UV–vis spectroscopy. A plot of the static dielectric constant as a function of the surfactant concentration was obtained using a suitable equivalent circuit to elaborate impedance data. Experimental points can be fitted by two different straight lines whose intersection occurs at about 0.13% (w/w) concentration of Dynol. When the surfactant concentration crossed the aforementioned value, a peak was detectable in the UV–vis spectrum at a wavelength range corresponding to the absorption of MO; absorbance of the peak increased with the surfactant conc…
On the variations of acoustic absorption peak with particle velocity in micro-perforated panels at high level of excitation.
2010
The acoustic behavior of micro-perforated panels (MPP) is studied theoretically and experimentally at high level of pressure excitation. A model based on Forcheimer's regime of flow velocity in the perforations is proposed. This model is valid at relatively high Reynolds numbers and low Mach numbers. The experimental method consists in measuring the acoustical pressure at three different positions in an impedance tube, the two measurement positions usually considered in an impedance tube and one measurement in the vicinity of the rear surface of the MPP. The impedance tube is equipped with a pressure driver instead of the usual loudspeaker and capable of delivering a high sound pressure lev…
Highly efficient isotope separation and ion implantation of 163Ho for the ECHo project
2019
Abstract The effective electron neutrino mass measurement in the framework of the ECHo experiment requires radiochemically pure 163 Ho, which is ion implanted into detector absorbers. To meet the project specifications in efficiency and purity, the entire process chain of ionization, isotope separation , and implantation of 163Ho was optimized. A new two-step resonant laser ionization scheme was established at the 30 kV magnetic mass separator RISIKO. For ionization and separation, an average efficiency of 69 ( 5 ) stat(4)sys% was achieved using intra-cavity frequency doubled Ti:sapphire lasers. The implantation of undesired 166 m Ho, which is present in trace amounts in the initial 163Ho…
Modeling the anaerobic treatment of sulfate rich urban wastewater. Application to AnMBR technology
2020
[EN] Although anaerobic membrane bioreactors (AnMBR) are a core technology in the transition of urban wastewater (UWW) treatment towards a circular economy, the transition is being held back by a number of bottlenecks. The dissolved methane released from the effluent, the need to remove nutrients (ideally by recovery), or the energy lost by the competition between methanogenic and sulfate-reducing bacteria (SRB) for the biodegradable COD have been identified as the main issues to be addressed before AnMBR becomes widespread. Mathematical modeling of this technology can be used to obtain further insights into these bottlenecks plus other valuable information for design, simulation and contro…
The modelling of the cathode sheath of an electrical arc in vacuum
2003
This paper presents a simple model of the fragment in the cathode electrical arc root taking into account the physical phenomena occuring on the cathode surface and the sheath. The goal is the obtainment of characteristics values of the heat flux, the electrons, and atoms density in the sheath. Computation is carried out on a one-dimensional model with a coupling between the equation obtained in the sheath and an enthalpy model of the cathode to describe the temperature evolution. In the modelling, we introduce a friction zone above the sheath edge to characterize the heavy particle interactions. Numerical simulation shows that the ionic friction phenomenon deriving from ion–atom collision …
Design of nonionic surfactants for supercritical carbon dioxide
1996
Interfacially active block copolymer amphiphiles have been synthesized and their self-assembly into micelles in supercritical carbon dioxide (CO 2 ) has been demonstrated with small-angle neutron scattering (SANS). These materials establish the design criteria for molecularly engineered surfactants that can stabilize and disperse otherwise insoluble matter into a CO 2 continuous phase. Polystyrene- b -poly(1,1-dihydroperfluorooctyl acrylate) copolymers self-assembled into polydisperse core-shell-type micelles as a result of the disparate solubility characteristics of the different block segments in CO 2 . These nonionic surfactants for CO 2 were shown by SANS to be capable of emulsifying u…