Search results for "composition"

Improvement of Biomass Gasification/Combustion Characteristics by Microwave Pretreatment of Biomass Pellets

2021

Characterization of refuse derived fuel production from municipal solid waste: the case studies in Latvia and Lithuania

2020

Abstract The authors determined the morphological composition of refuse derived fuel (RDF) produced in Latvia and Lithuania by manually sorting. The parameters of RDF (moisture, net calorific value, ash content, carbon, nitrogen, hydrogen, sulphur, chlorine, metals) was determined using the EN standards. Comparing obtained results with data from literature, authors have found that the content of plastic is higher but paper and cardboard is lower than typical values. Results also show that the mean parameters for RDF can be classified with the class codes: Net heating value (3); chlorine (3); mercury (1), and responds to limits stated for 3rd class of solid recovered fuel. It is recommended …

Composition, structure and evolution of the early Precambrian lower continental crust: constraints from geological observations and age relationships

1986

Comparison of parallel implementation of some multi-level Schwarz methods for singularly perturbed parabolic problems

1999

Abstract Parallel multi-level algorithms combining a time discretization and an overlapping domain decomposition technique are applied to the numerical solution of singularly perturbed parabolic problems. Two methods based on the Schwarz alternating procedure are considered: a two-level method with auxiliary “correcting” subproblems as well as a three-level method with auxiliary “predicting” and “correcting” subproblems. Moreover, modifications of the methods using time extrapolation on subdomain interfaces are investigated. The emphasis is given to the description of the algorithms as well as their computer realization on a distributed memory multiprocessor computer. Numerical experiments …

Digital Technologies for Cultural Heritage Preservation. A case study.

2014

Within the study and knowledge of Cultural Heritage, the Virtual Restoration represents an innovative technical-scientific sector that involves the use of Information and Communications Technologies (ICT) within traditional and well-established methodologies. The study illustrates a practical experience carried out on a cycle of sculptural works made in stucco that currently shows a number of fragmentary and disjointed parts. In this research a methodological approach is described, whose aim was to build a 3D model and formulate an hypothesis of virtual recomposition of the fragments. In addition, it provided useful geometrical-formal support tools both for the physical-material restoration…

Growth potential of Listeria monocytogenes strains in mixed ready-to-eat salads

2009

In this study, a microbiological challenge test in three artificially contaminated retail mixed mayonnaise-based ready-to-eat salads stored at refrigerator temperatures (3°C and 7°C) for 48h was carried out. Shrimp-tomato salad, smoked ham salad and garlic cheese salad were separately contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes, Enterobacteriaceae, staphylococci and total plate count (CFU/g) was determined. Listeria monocytogenes growth potential in the salads was calculated and evaluated. A significant increase in total plate count and L. monocytogenes count throughout storage of all three investigated salads was found. Enteroba…

Conditions et enjeux pédagogiques de la constitution de classes à cours multiples dans les écoles primaires

2006

06022; La problématique de cette recherche s'inscrit dans le schéma global suivant, qui se donne pour objectif d'analyser successivement les pratiques de constitution des classes (nombre et nature des classes au sein des écoles), les modalités d'affectation des élèves et des enseignants dans ces classes et enfin l'efficacité pédagogique des différents types de groupement réalisés.

Between striated and smooth space: Exploring the topology of transnational student mobility

2017

In this paper, we raise a question regarding how transnational students develop their spaces as mobile, temporary, and at times stable and territorially fixed. We argue that approaching transnational student migration and its relations to place as a Deleuzian assemblage is a fruitful way of highlighting this issue, and we propose the axes of the expressive/material and territorialisation/de-territorialisation as analytical tools for understanding aspects of the temporal and spatial dimensions of transnational student mobility. Our theoretical discussion is informed by the migration experiences of transnational students studying at a Norwegian university. Our core argument is that transnatio…

Palladium-ADC complexes as efficient catalysts in copper-free and room temperature Sonogashira coupling

2014

Abstract The metal-mediated coupling between cis-[PdCl2(CNR1)2] [R1 = cyclohexyl (Cy) 1, t-Bu 2, 2,6-Me2C6H3 (Xyl) 3, 2-Cl-6-MeC6H3 4] and hydrazones H2NN CR2R3 [R2, R3 = Ph 5; R2, R3 = C6H4(OMe-4) 6; R2/R3 = 9-fluorenyl 7; R2 = H, R3 = C6H4(OH-2) 8] provided carbene complexes cis-[PdCl2{C(N(H)N CR2R3) N(H)R1}(CNR1)] (9–24) in good (80–85%) yields. Complexes 9–24 showed high activity [yields up to 99%, and turnover numbers (TONs) up to 3.7 × 104] in the Sonogashira coupling of various aryl iodides with a range of substituted aromatic alkynes without the need of copper co-catalyst. The catalytic procedure runs at 80 °C for 1 h in EtOH using K2CO3 as a base. No formation of homocoupling or ac…

Combined CO/CH4 oxidation tests over Pd/Co3O4 monolitic catalyst: effects of high reaction temperature and SO2 exposure on the deactivation process

2007

Abstract CO and CH 4 combined oxidation tests were performed over a Pd (70 g/ft 3 )/Co 3 O 4 monolithic catalyst in conditions of GHSV = 100,000 h −1 and feed composition close to that of emission from bi-fuel vehicles. The effect of SO 2 (5 ppm) on CO and CH 4 oxidation activity under lean condition ( λ  = 2) was investigated. The presence of sulphur strongly deactivated the catalyst towards methane oxidation, while the poisoning effect was less drastic in the oxidation of CO. Saturation of the Pd/Co 3 O 4 catalytic sites via chemisorbed SO 3 and/or sulphates occurred upon exposure to SO 2 . A treatment of regeneration to remove sulphate species was attempted by performing a heating/coolin…