1,865 research outputs found
Modelo de maturidade de excelência operacional : estudo de caso em empresa do setor plástico
Orientador : Prof. Dr. Marcelo Gechele CletoDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia de Produção. Defesa : Curitiba, 23/02/2018Inclui referênciasResumo:Abstract
Laser powder bed fusion recoater selection guide: comparison of resulting powder bed properties and part quality
Spreading devices used to create powder layers in the laser powder bed fusion of metals (PBF-LB/M) were found to have a significant impact on the additive manufacturing process. However, previous research primarily focused on theoretical investigations, including recoater concepts that are not available on the market, while no comprehensive comparison of commercially available spreading devices currently exists. The aim of this study is therefore to examine the powder bed properties and part qualities that can be achieved with the three most common types of recoater: carbon fiber brushes, polymer lips, and high speed steel (HSS) blades. Identical build jobs were produced using each of the spreading devices. Their capabilities were assessed by nine evaluation criteria, including dimensional, metallurgical, and mechanical properties and criticality of particles abraded from the spreading devices. Based on these quantitative findings, a spreading device selection guide was compiled for the benefit of PBF-LB/M practitioners. All recoaters yielded processes with high stability and part properties that were on a par with or even outperformed the nominal values from the literature. However, the HSS blade was found to provide higher accuracy and stability in steady-state processes. In turn, the brush and lip are better suited for parameter development and design studies. Additionally, the lip was found to have economic benefits over the brush, while the brush was deemed an effective all-rounder
A novel multiplex qPCR targeting 23S rDNA for diagnosis of swine dysentery and porcine intestinal spirochaetosis
Figure S1. Consensus sequence alignment of the target DNA region within 23S ribosomal DNA. Primers (Brachy primer for. and Brachy primer rev.) on the target DNA are marked in grey. The probe for B. hyodysenteriae (Probe_hyo) is highlighted in yellow, the probe for B. pilosicoli (Probe_pilo) in purple, and the probe for the B. intermedia/B. innocens/B. murdochii (probe inter) in green. Differences in single residues are marked in red. (PDF 112 kb
Ferroelectricity and Crystal Phases in Mixed‐Cation Lead Iodide Perovskite Solar Cells
After the discovery of ferroelectricity in archetypal methylammonium lead iodide (MAPbI), the discussion arose, if more advanced derivatives thereof are also ferroelectric and to what extent the polar domains mitigate detrimental charge carrier recombination in perovskite solar cells. Herein, the A-site cation methylammonium is gradually substituted with formamidinium and cesium. The domain contrast measured by piezoresponse force microscopy is correlated with the distortion of the crystal structure measured by X-ray diffraction. By Rietveld analysis, a detailed structural model together with texture information is determinded, which reveals an intriguing interplay between lead iodide and the perovskite phases. Finally, the bearing of ferroelectric domains in mixed-cation perovskites on the solar cell performance is discussed
Condensation Coefficient Measurement for Water in the UMR Cloud Simulation Chamber
A systematic series of condensation coefficient measurements of water have been made using the University of Missouri-Rolla cooled-wall expansion chamber which simulates the thermodynamics of cloud. This coefficient is seen to decrease from a value near unity, at the outset of simulation, to a value in the neighborhood of 0.01 toward the end of a simulation. Final values of this coefficient are sufficiently low as to contribute significantly to the broadening of the drop-size distribution in cloud
Measurement of the Condensation Coefficient of Water in the UMR Simulation Chamber
The UMR Cloud Simulation Facility is described. The facility is designed to provide a controlled environment simulating the conditions of natural atmospheric processes. It consists of two cooled-wall expansion cloud chambers and peripheral instrumentation for generation and characterization of aerosols used for cloud formation studies. Results of initial studies of the growth of warm cloud droplets and inferred measurements of the condensation coefficient are described
Remix como conteúdo jornalístico: um estudo sobre “Game of Thrones”
Esse trabalho tem como tema a recirculação de acontecimentos na forma de imagens remixadas com a temática do seriado Game of Thrones. O ensaio traz como problema a identificação do remix enquanto conteúdo jornalístico e aprofunda duas hipóteses: a) a combinação de imagens realizadas pelos fãs não tem relação com o jornalismo; b) a combinação de imagens traz novas camadas de significação ao fato. Para responder à primeira hipótese, utilizam-se como métodos a pesquisa bibliográfica e a análise de conteúdo categorial. Para a segunda hipótese, é feita uma análise de discurso nas postagens e os comentários são divididos em categorias. Ao fim do estudo, conclui-se que as imagens remixadas trazem novos sentidos para notícias, séries e demais fatos divulgados em meios de comunicação, porém, não podem ser consideradas produtos jornalísticos
A Systematic Review of Atypical Teratoid Rhabdoid Tumor in Adults
Background: Atypical teratoid/rhabdoid tumor in adults is a relatively rare malignant neoplasm. It is characterized by the presence of rhabdoid cells in combination with loss of either the INI1 or BRG1protein from the tumor cells.Methods: A systematic review was conducted using MEDLINE using the terms “atypical teratoid rhabdoid tumor” AND “adult.” The systematic review was supplemented with relevant articles from the references. Cases were included if the pathology was confirmed by loss of INI1 or BRG1. We included a case from our institution. The dataset was analyzed using descriptive statistics and log-rank test.Results: A total of 50 cases from 29 articles were included in this study. The average age at diagnosis was 36.7 years. The most common locations reported are the sellar region and cerebral hemispheres (without deep gray matter involvement). Of the 50 cases, 14 were reported to show evidence of dissemination. The average overall survival was 20 months. There was a significant difference in survival between the adjuvant therapy groups (p = < 0.0001).Conclusion: Atypical teratoid rhabdoid tumor of the central nervous system in adults is a rare neoplasm associated with a poor prognosis in a majority of patients. The treatment and clinical course are highly variable, and it remains unclear which factors impact prognosis
Measurement of the Condensation Coefficient of Water in the UMR Cloud Simulation Chamber
Measurements of the condensation coefficient of water under conditions closely approximating those in natural atmospheric cloud have been made in the cooled-wall UMR cloud simulation chamber. Current measurements disclose a value of condensation coefficient near unity at the outset of the experiment, generally decreasing to lower values (~ .01) as the experiment progresses. The significance of the magnitude of condensation coefficient in atmospheric cloud is briefly discussed
NGC6240: Merger-Induced Star Formation & Gas Dynamics
We present spatially resolved integral field spectroscopic K-band data at a
resolution of 0.13" (60pc) and interferometric CO(2-1) line observations of the
prototypical merging system NGC6240. Despite the clear rotational signature,
the stellar kinematics in the two nuclei are dominated by dispersion. We use
Jeans modelling to derive the masses and the mass-to-light ratios of the
nuclei. Combining the luminosities with the spatially resolved Br-gamma
equivalent width shows that only 1/3 of the K-band continuum from the nuclei is
associated with the most recent star forming episode; and that less than 30% of
the system's bolometric luminosity and only 9% of its stellar mass is due to
this starburst. The star formation properties, calculated from typical merger
star formation histories, demonstrate the impact of different assumptions about
the star formation history. The properties of the nuclei, and the existence of
a prominent old stellar population, indicate that the nuclei are remnants of
the progenitor galaxies' bulges.Comment: 18 pages, 14 figures. Accepted for publication in A&
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