Search results for "racking"

Cardiac sarcoidosis: Matching speckle tracking echocardiography to macroscopic Ventricular pathology (a case report)

2016

Hot cracking in Al–Mg–Si alloy laser welding – operating parameters and their effects

2005

Abstract Hot cracking is a phenomenon that frequently occurs in the laser welding of some “special” alloys, such as the aluminium–magnesium–silicon type. Each occurrence of this phenomenon needs to be studied in itself, taking into account not only the individual, but also the interactive, influences of the various parameters. The advantage of using laser beams in welding processes lies in the speeds that can be reached. The disadvantage, however, is that, owing to the high cooling rates characteristic of the interaction between the laser beam and the material, the welding speed itself becomes a cause of hot cracking. The aim of this paper is to see how this disadvantage may be eliminated. …

The role of pore topology on the behaviour of FCC zeolite additives

1999

Abstract A large variety of zeolite topologies including: large pore tridirectional (Beta), large pore unidirectional (Mordenite, SSZ-24), bidirectional 10 member ring pores (MRP) (ZSM-5), bidirectional 10 × 8 MRP (Ferrierite), tridirectional with connected 12 and 10 MRP (CIT-1), bidirectional with 12 MRP connected by 10 MRP (NU-87), tridirectional with 10 × 11 × 12 MRP (NU-86), and finally 10 MRP, and independent 12 MR cavities connected by 10 MR windows (MCM-22), have been studied as catalysts for the cracking of a gasoline range model molecule ( n -heptane). Kinetic and decay constants as well as selectivity parameters such as paraffin/olefin, i -C 4 / n -C 4 , i -C 5 / n -C 5 , C 3 /C 4…

Catalytic activity of large-pore high Si/Al zeolites: Cracking of heptane on H-Beta and dealuminated HY zeolites

1987

Abstract The catalytic activity, selectivity, catalyst decay, thermal and hydrothermal stability, and acidity of H-Beta and HY zeolites with Si Al ratios of 7.5 and 10, respectively, have been studied during cracking of n-heptane at 450 °C and atmospheric pressure. It has been found that the H-Beta zeolite is more active and decays more slowly than HY. H-Beta presents a higher steric hindrance for dibranched molecules and therefore its open structure should be smaller than that of HY. A lower hydrogen transfer activity and hydrothermal stability is observed for H-Beta in comparison with the corresponding HY.

Mostrare l’invisibile: il soffitto trecentesco nascosto del convento di Santa Caterina a Palermo

2022

Digital surveying and representation technologies have been widely used for the visualization of works of art and architecture that no longer exist or have been moved from their original location. These researches share a common feature, that can be resumed by the motto “Display the invisible”, already used in research experiences [Colosi et al. 2015; Gambin et al. 2021]. The purpose of this research is the visualization of a 14th century wooden ceiling, painted by anonymous artists, that covered the hall used for the assembly of the Chapter in the convent of Santa Caterina, at the heart of the historic center of Palermo. The hall was reshaped at the end of the 18th century to serve as a sa…

Etude et modélisation du comportement des gouttelettes de produits phytosanitaires sur les feuilles de vignes par imagerie ultra-rapide et analyse de…

2013

In the domain of vineyard precision spraying research, one of the most importantobjectives is to minimize the volume of phytosanitary products ejected bya sprayer in order to be more environmentally respectful with more effectivevine leaf treatments. Unfortunaltely, even if lot of works have been carriedout at a parcel scale, mainly on losses caused by drift, less works have beencarried out at the leaf scale in order to understand which parameters influencethe spray quality. Since few years, recent improvements in image processing,sensitivity of imaging systems and cost reduction have increased the interestof high-speed imaging techniques. Analyzing the behavior of droplets afterimpact with…

2020

Domain-specific understanding of digitally represented graphs is necessary for successful learning within and across domains in higher education. Two recent studies conducted a cross-sectional analysis of graph understanding in different contexts (physics and finance), task concepts, and question types among students of physics, psychology, and economics. However, neither changes in graph processing nor changes in test scores over the course of one semester have been sufficiently researched so far. This eye-tracking replication study with a pretest-posttest design examines and contrasts changes in physics and economics students' understanding of linear physics and finance graphs. It analyze…

Reconstruction of Micropattern Detector Signals using Convolutional Neural Networks

2017

Micropattern gaseous detector (MPGD) technologies, such as GEMs or MicroMegas, are particularly suitable for precision tracking and triggering in high rate environments. Given their relatively low production costs, MPGDs are an exemplary candidate for the next generation of particle detectors. Having acknowledged these advantages, both the ATLAS and CMS collaborations at the LHC are exploiting these new technologies for their detector upgrade programs in the coming years. When MPGDs are utilized for triggering purposes, the measured signals need to be precisely reconstructed within less than 200 ns, which can be achieved by the usage of FPGAs. In this work, we present a novel approach to id…

A multidisciplinary approach to the study of cultural heritage environments: Experience at the Palatina Library in Parma

2015

The aim of this paper is to describe a multidisciplinary approach including biological and particle monitoring, and microclimate analysis associated with the application of the Computational Fluid Dynamic (CFD). This approach was applied at the Palatina historical library in Parma. Monitoring was performed both in July and in December, in the absence of visitors and operators. Air microbial monitoring was performed with active and passive methods. Airborne particles with a diameter of ≥0.3, ≥0.5, ≥1 and ≥5 μm/m3, were counted by a laser particle counter. The surface contamination of shelves and manuscripts was assessed with nitrocellulose membranes. A spore trap sampler was used to identify…

Relationship between radial and concentric cracking of tomato fruit

1983

Abstract A study with 62 genotypes was carried out to establish correlations existing between the percentages of fruits showing concentric cracks of more or less than 2 cm and radial cracks of more or less than 2 cm, considering both early and total production. Over a determined productive period, the susceptibility to form large or small cracks was controlled by the same genetic system (rG = 0.89 – 0.95), yet there was a genetic difference between susceptibility to radial and concentric cracking (rG = 0.53 – 0.68). Genetic systems for susceptibility to radial and concentric cracking seemed to show similarly over the first harvesting and over the total productive period ( r G ⋍ 1 ). Environ…