1,724,187 research outputs found
Performance assessment of ISO-5167 and symmetrical Venturi meters for measuring low Reynolds number turbulent incompressible isothermal flow
Get PDFThe selection of Venturis depends on the desired flow measurement sensitivity, permanent pressure loss, discharge coefficient, and relative pressure loss coefficient. The ISO-5167 standard specifies geometries for Venturi metres within the Reynolds number range of 200,000 to 2,000,000. This study evaluates the performance of ISO-5167 and six suggested symmetrical Venturis operating in both unidirectional and bidirectional flow conditions for flows with Reynolds numbers below 200,000. The performance of ISO-5167 and six suggested symmetrical Venturis with β-ratios of 0.4 and 0.55, and cone angles of 10°, 20°, and 40° degrees were evaluated. The study found that the ISO-5167 Venturi performed best in the conventional flow direction for flows with Reynolds numbers greater than ≈34,000. The symmetrical Venturi meter with a β-ratio of 0.55 and a cone angle of 10° (SVD4) exhibited performance comparable to the ISO-5167 Venturi for the conventional flow direction. The ISO-5167 Venturi exhibited a significant flow reversal when operating in the opposite direction to the conventional flow. The SVD4 Venturi metre demonstrated the potential to save 71 % of energy in the reverse flow direction compared to the ISO-5167 Venturi, suggesting an energy saving of up to 43 % in certain bi-directional flow scenarios
Metamorphic angrite Northwest Africa 3164/5167 compared to magmatic angrites
No full textInternational audienceNorthwest Africa (NWA) 3164 and 5167 are two angrites with a granulitic texture unlike that of other angrites, with avariable, up to millimeter grain size. Besides mineralogical and chemical similarities to other angrites, NWA 3164 and5167 exhibit unique characteristics. Ca-rich olivine dominates (in NWA 3164: 49 vol%, Fo57; NWA 5167: 40 vol%,Fo59). Fassaitic clinopyroxene is the second major phase (in NWA 3164: 29 vol%; in NWA 5167: 36 vol%) with a significantTschermak component. In addition, two Al-rich phases are present: plagioclase An99 and hercynitic spinel (6 and 7 vol%respectively for NWA 3164; 17 and 4 vol% respectively for NWA 5167). Heavily weathered iron sulfide and kamacite, (9 wt%in NWA 3164; 4 wt% in NWA 5167) are the remaining minor phases, a unique feature among angrites. All mineral phases arehomogeneous. Like other angrites, NWA 3164 and 5167 exhibit a superchondritic Ca/Al ratio, with negligible amounts ofalkalis and very low silica content. The presence of metal results from the incorporation of exogenous iron following impact.Subsequent annealing resulted in the observed granulitic texture. Major element composition indicates that both NWA 3164and 5167 are derived from a picritic angrite precursor after incorporation of metal and annealing.After correction for iron and Fo90 olivine incorporation, bulk rock REE abundances of both NWA 3164 and NWA 5167appear lower than those of quenched angrites, showing the lowest absolute abundances among angrites. Laser ablation inductivelycoupled plasma mass spectrometry (LA-ICP-MS) analyses of clinopyroxene, olivine and anorthite indicate that differenceof Rare Earth Element (REE) abundances between NWA 3164 and NWA 5167 can be explained by adding traces ofphosphate to NWA 3164. NWA 3164/5167 trace elements abundances are similar, showing depletion in volatile elementsand enrichment in refractory lithophile elements such as Ca, Ti, and Al. The most incompatible elements are depleted as well,unlike other angrites. This indicates that the source of these younger angrites was more depleted in incompatible elementswhen compared to the older magmatic angrites. The low Hf/W is understood as the result of exogenous iron incorporationand therefore the Hf/W andWisotopic heterogeneity of the angrite parent body (APB) mantle is secondary. Comparison withother angrites suggests that iron incorporation may be necessary to explain their low Hf/W and W isotopic compositions
Block Card 5167 Ketukkee Trail
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: dwelling | 5167 Ketukkee Trail (Toledo, Ohio) | Ranch houses | Greenwich Village (Toledo, Ohio) | Point Place (Toledo, Ohio) | North Toledo (Toledo, Ohio
Merenje protoka pomoću mernih blendi - poređenje rezultata proračuna protoka prema standardima ISO 5167:1989 i ISO 5167:2007
Get PDFMerenje protoka fluida je jedno od osnovnih merenja koje se obavlja u procesnoj tehnici, termotehnici, energetici i mnogim drugim oblastima tehnike. Zavisno od potreba potrebno je odabrati odgovarajući metod, kojim može da se sprovede merenje na najjednostavniji način, uz dovoljnu tačnost, i uz najmanje ometanje tehnološkog postupka. Merenje protoka pomoću mernih blendi se svodi na ugradnju merne blende u cevovod kružnog preseka i posredno utvrđivanje protoka merenjem razlike pritisaka ispred i iza blende. Ovaj metod je veoma čest u industrijskoj praksi, jer je normiran kroz standarde kao što su npr. SRPS EN ISO 5167:2012 „Merenje protoka fluida pomoću uređaja sa diferencijalnim pritiskom ugrađenih u cevovode kružnog poprečnog preseka - Deo 1: Opšti principi i zahtevi“ koji je identičan sa EN ISO 5167-1:2003 ili ASME MFC-14M-2001 „Measurement of fluid flow using small bore precision orifice meters”. Proračunska procedura pomoću koje se izračunava protok fluida je u važećem standardu SRPS EN ISO 5167:2012 drugačija nego u prethodnim izdanjima istog standarda 1980., 1989., 1993., kao i iz 1998. Imajući ovo u vidu postavlja se pitanje da li se i za koliko razlikuju izračunati protoci fluida, pa je u ovom radu analizirano nekoliko konkretnih slučajeva. U pitanju su merenja na industrijskim instalacijama, kao i merenja obavljena u Laboratoriji za procesnu tehniku na Mašinskom fakultetu u Beogradu
Abstract 5167: Notch1 is required for endothelial cell lineage differentiation from adult bone marrow stem cells <i>in vitro</i>
No full textAbstract
Background and Objectives. Adult bone-marrow stem cells (BMSCs) are able to differentiate into endothelial progenitor cells (EPCs) and subsequently endothelial cells (ECs) under appropriate conditions. BMSCs-derived EPCs/ECs contribute to post-natal neovascularization and are important tools for regenerative medicine. However, the molecular mechanism determining specific differentiation of endothelial lineage remains unknown. The Notch signaling pathway plays an integral role in the differentiation of a variety of cell lineages. We hypothesize that Notch signaling is involved in controlling endothelial lineage differentiation from BMSCs and examined the role of Notch1 signaling in this process.
Methods and Results. An in vitro method for differentiation of endothelial cell lineage from murine BMSCs was developed. Mononuclear cells were isolated from mouse whole BM cells by light density separation using Ficoll-Paque® Plus, and cultured in the differentiation medium to differentiate endothelial cells. The endothelial phenotype of differentiated cells was characterized by immunostaining and flow cytometry analyses. Those fractions of cells with VEGFR2+/CD31+ or Tie2+/CD31+ were isolated and tested. VEGFR2+/CD31+ cells could form networks on the MatrigelTM, indicating that these cells are ECs. mRNA expression of Notch pathway components in VEGFR2+/CD31+ cells was examined by real-time RT-PCR. Multiple components of the Notch signaling pathway were expressed in the differentiated ECs. The effect of loss-of-function in Notch1 on the differentiation of endothelial cell lineage was examined using BMSCs from Notch1Flox/Flox mice. Cells expressing VEGFR2 were significantly decreased when Notch1 is deleted.
Conclusions. A novel and reliable method has been developed to differentiate murine adult bone marrow stem cells into endothelial cell lineage in vitro. The role of Notch1 in determining endothelial cell differentiation was tested on this platform. Our results implicated that Notch1 is required for the differentiation of endothelial cell lineage from BMSCs.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5167.</jats:p
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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