392 research outputs found
Scintillation efficiency of liquid argon in low energy neutron-argon scattering
Experiments searching for weak interacting massive particles with noble gases
such as liquid argon require very low detection thresholds for nuclear recoils.
A determination of the scintillation efficiency is crucial to quantify the
response of the detector at low energy. We report the results obtained with a
small liquid argon cell using a monoenergetic neutron beam produced by a
deuterium-deuterium fusion source. The light yield relative to electrons was
measured for six argon recoil energies between 11 and 120 keV at zero electric
drift field.Comment: 21 pages, 19 figures, 4 table
Nucleation and Growth of the Zn-Fe Alloy from a Chloride Electrolyte
In this study, the kinetics of Zn-Fe codeposition was investigated in chloride acidic solution using
cyclic voltammetry. Anomalous codeposition is detected and this mechanism depends on the Zn(II) / Fe(II)
concentration ratio in the electrolytic bath. The study of early stages of electrodeposition showed that Zn-
Fe follows a theoretical response to instantaneous nucleation evolves into a progressive nucleation
according to the model of Scharifker and Hills. The morphology and structure of the coatings is discussed
using characterization techniques. Dense, uniform, and singlephased Zn-Fe coatings could be obtained
with a Zn-Fe ratio of 1/3.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3531
Controvèrsia al voltant de la Vacuna pel Virus del Papil·loma Humà. Era necessària la vacunació global a Espanya?
Experimental verification of the stefan-boltzmann law in the physics iii course of the engineering department of La Plata university
Facultad de Ingeniera de la Universidad Nacional de La Plata abarca dos módulos bimestrales. En el segundo de ellos se abordan temas de Física Moderna y entre las actividades de laboratorio establecidas, los alumnos realizan un experimento donde comprueban la ley de Stefan-Bolztmann determinando la dependencia funcional de la irradiancia emitida por un cuerpo negro con su temperatura absoluta utilizando un cubo de Leslie. En el presente trabajo se describe el instrumental utilizado en el laboratorio, la metodología experimental realizada por los alumnos, se presentan las mediciones realizadas y se analiza la relación funcional entre la irradiancia emitida por el cubo de Leslie y su temperatura comprobando la Ley de Steffan-Boltzmann. Además, se determina el valor de la constante de Stefan-Boltzmann (V) analizando la relación de la radiación electromagnética emitida por la cara negra del cubo con su temperatura. Palabras Claves: Stefan-Boltzmann, cuerpo negro, temperatura, Ingeniería, laboratorio. (hasta 6)The Physics IIIA course of the Electronic, Electric and Chemical Engineering degrees of La Plata University includes two modules of two months each. The second teaching module includes Modern Physics topics and laboratory activities where students perform an experiment to verify the Stefan-Boltzmann law where they get the dependency of the radiation of the black body with the absolute temperature of the Leslie cube. In the present work, we describe the experimental methodology, the experimental equipment and we analyze the temperature dependence of the radiation emitted by the Leslie cube. Finally, we verified the Stefan-Boltzmann law and determine the Stefan-Bolzmann constant (V) from the temperature dependence of the radiation emitted by the black face of the Leslie cube.Fil: Muñoz, Emiliano Luis. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Instituto de Física La Plata; ArgentinaFil: Creus, M.. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigaciones Opticas (i); ArgentinaFil: Sanjuan, F.. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigaciones Opticas (i); ArgentinaFil: Rabal, Hector Jorge. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Investigaciones Opticas (i); ArgentinaFil: Gallego, J.. Universidad Nacional de La Plata. Facultad de Ingenieria; Argentin
Effects of red wine and different doses of polyphenols from dealcoholised red wine on endothelial function in subjects with metabolic syndrome
Podeu consultar el III Workshop anual INSA-UB complet a: http://hdl.handle.net/2445/118993Sessió 1. Pòster núm.
The Dugald River-type, shear zone hosted, Zn-Pb-Ag mineralisation, Mount Isa Inlier, Australia
The Dugald River Zn-Pb-Ag mine is situated in the Mount Isa Inlier, a globally significant base metal province. Zn-Pb deposits in the Mount Isa Inlier are stratabound with four main genetic models, including SEDEX-style, remobilised SEDEX, epigenetic and Broken Hill-type mineralisation applied to interpret their formation. We propose that the Zn-Pb-Ag mineralisation at Dugald River represents a unique, shear zone hosted deposit type that formed through a series of successive deformation events during the Paleoproterozoic Isan Orogeny that concentrated the mineralisation within the Dugald River Shear Zone during two main mineralising phases. The first phase of mineralisation occurred during regional D2 shortening, which is associated with the formation of large-scale F2 folds and a regionally penetrative S2 fabric. During this phase, progressive tightening of upright F2 folds resulted in several sets of secondary space accommodating quartz-carbonate veins that were progressively rotated into parallelism with the pervasive, steep, W-dipping S2 cleavage. The quartz-carbonate veins were coevally replaced by sulphides, which migrated to extensional sites (boudin necks and fold hinges) in tight folds. Thereby creating a sulphide-rich horizon within a developing high strain zone, which during D4 developed into the Dugald River Shear Zone. The second phase of mineralisation occurred during the regional D4 transpressional deformation event and resulted in significant metal enrichment and the current geometry of the ore bodies. The significant enrichment of the mineralisation during D4 resulted from further fold tightening within the high strain zone, which resulted in the attenuation and dismembering of folds and produced a transposed fabric (S4). The sulphide veins were transposed into parallelism with S4 forming sulphide-rich planar ore textures. Strain partitioning at the contact between the ductile deforming sulphide horizon and the brittle deforming slates resulted in the development of an anastomosing shear zone, known as the Dugald River Shear Zone. A right-handed releasing bend in the shear zone produced a dilational jog and a thick, high-grade ore body. The mobilisation of sulphides within the dilational jog involved fragmentation of sulphides and wall rock, brecciation, rotation and rolling of fragments, and the formation of durchbewegung texture
Warm Compressor system Overview and status of the PIP-II cryogenic system
The Proton Improvement Plan-II (PIP-II) is a major upgrade to the Fermilab
accelerator complex, featuring a new 800-MeV Superconducting Radio-Frequency
(SRF) linear accelerator (Linac) powering the accelerator complex to provide
the world's most intense high-energy neutrino beam. The PIP-II Linac consists
of 23 SRF cryomodules operating at 2 K, 5 K, and 40 K temperature levels
supplied by a single helium cryoplant providing 2.5 kW of cooling capacity at
2.0 K. The PIP-II cryogenic system consists of two major systems: a helium
cryogenic plant and a cryogenic distribution system. The cryogenic plant
includes a refrigerator cold box, a warm compressor system, and helium storage,
recovery, and purification systems. The cryogenic distribution system includes
a distribution box, intermediate transfer line, and a tunnel transfer line
consisting of modular bayonet cans which supply and return cryogens to the
cryomodules. A turnaround can is located at the end of the Linac to turnaround
cryogenic flows. This paper describes the layout, design, and current status of
the PIP-II cryogenic system.Comment: 2023 Cryogenic Engineering Conference and International Cryogenic
Materials Conference (CEC/ICMC
Reconstrucción paleoclimática y paleoambiental de la Península Ibérica durante el Cuaternario, aplicación de modelos geoprospectivos para la evaluación de escenarios futuros
Esta comunicación trata de resumir el trabajo realizado por el ITGE, BRGM, CCMA, IPE, ETSIMM y ENRESA en el proyecto titulado "Paleoclimatological Revision of Climate Evolution and Environment in Western Mediterranean Region. Evaluation of future evolution scenarios in the Iberian Peninsula", en el marco del Programa de la Comisión de las Comunidades Europeas sobre Gestión y Almacenamiento de Residuos Radioactivos (contrato CEC FI2WCT91- 0075)
Cross-feeding between intestinal pathobionts promotes their overgrowth during undernutrition
Child undernutrition is a global health issue associated with a high burden of infectious disease. Undernourished children display an overabundance of intestinal pathogens and pathobionts, and these bacteria induce enteric dysfunction in undernourished mice; however, the cause of their overgrowth remains poorly defined. Here, we show that disease-inducing human isolates of Enterobacteriaceae and Bacteroidales spp. are capable of multi-species symbiotic cross-feeding, resulting in synergistic growth of a mixed community in vitro. Growth synergy occurs uniquely under malnourished conditions limited in protein and iron: in this context, Bacteroidales spp. liberate diet- and mucin-derived sugars and Enterobacteriaceae spp. enhance the bioavailability of iron. Analysis of human microbiota datasets reveals that Bacteroidaceae and Enterobacteriaceae are strongly correlated in undernourished children, but not in adequately nourished children, consistent with a diet-dependent growth synergy in the human gut. Together these data suggest that dietary cross-feeding fuels the overgrowth of pathobionts in undernutrition
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