Zadržavanje plina u kontaktoru s turbulentnim slojem: eksperimenti i model predviđanja

Knowledge of gas holdup is important for the development of the three-phase fluidized bed reactors. This work concerns the study of the effect of different operating conditions on gas retention in a turbulent bed contactor type 2 (TBC), such as superficial gas and liquid velocities, liquid to gas mass flows ratio (L/G), particle diameter and density, static bed height and free-open area of the supporting grid. The influence of the free area of the packing support grid (φ) on gas holdup was demonstrated and proved. The gas holdup increased to 22.92 % when φ decreased from 0.82 to 0.32. The experimental data (1746) led to the development of two correlations to predict gas holdup, one of which incorporated the ratio (L/G) which is an important design factor for gas-liquid contactors. The predicted results of holdup gas were in good agreement with the experimental data.Poznavanje zadržavanja plina važno je za razvoj trofaznih reaktora s fluidiziranim slojem. Ovaj rad bavi se proučavanjem utjecaja različitih radnih uvjeta na zadržavanje plina u kontaktoru s turbulentnim slojem tipa 2 (TBC), kao što su površinske brzine plina i tekućine, omjer masenih protoka tekućine i plina (L/G), promjer čestica i gustoća, statička visina sloja i slobodna otvorena površina potporne rešetke. Dokazan je utjecaj slobodne površine potporne rešetke (φ) na zadržavanje plina. Zadržavanje plina povećalo se na 22,92 % kad se φ smanjio s 0,82 na 0,32. Iz dobivenih eksperimentalnih rezultata (1746) razvile su se dvije korelacije za predviđanje zadržavanja plina, od kojih je jedna uključivala omjer L/G, koji je važan faktor pri dizajnu plinsko-tekućinskih kontaktora. Predviđeni rezultati zadržavanja plina podudarali su se s eksperimentalnim podatcima

Eléments de réflexions autour de la pratique de l’analyse du discours en Algérie Repères & perspectives

ABSTRACT: The interest of this contribution is not to retrace the historical course of this practice in Algeria or elsewhere. It attempts to outline a reflection around the methodologies so solicited in the various researches already carried out, on the corpora apprehended, and secondly, to locate the specificities observed, to propose some avenues of reflection likely to characterize the career of a researcher in the domain of discourse analysis in Algeria, and to show what the steps specificity of this Discourse Analysis consists of in the Algerian context. RÉSUMÉ : L’intérêt de cette contribution n’est pas de retracer le parcours historique de l’analyse du discours en Algérie ou ailleurs. Elle tente une esquisse de réflexion autour des méthodologies tant sollicitées dans les différentes recherches déjà effectuées, sur les corpus appréhendés, et dans un second temps, situer les spécificités observées, proposer quelques pistes de réflexions susceptibles de caractériser le parcours d’un chercheur en analyse du discours en Algérie, et enfin, montrer en quoi consiste la spécificité de cette AD en contexte algérien

Antibacterial Activity of Sage Leaves against Pathogenic Bacteria as Affected by Different Drying Temperature

In the current study we investigated the influence of the drying methods and temperature on the phenolic content and the antibacterial activity of sage leaves. The in vitro antibacterial activity was evaluated against twelve bacteria, among them antibiotic susceptible and resistant microorganisms. The highest antimicrobial potentials were observed with the extracts dried at ambient and oven at 45°C which inhibited 8 types (66.67%) of the tested microorganisms. The sage extract derived from oven dried plant material at 60°C presented the highest polyphenol (13.79±0.11 mg GAE/g) content and at the same time the lowest antibacterial activity. The ethanol extract of sage had the greatest growth inhibition zone against Staphylococcus aureus (24 mm) and presented no antibacterial activity on: Escherichia coli ATCC; Klebsiellapneumoniae; Klebsiellaoxytoca and Enterobacteraerogenes.The results obtained with antibiotic-resistant bacteria (Acinetobacterbaumanniiand Protus mirabilis) were particularly interesting, since their cultures were inhibited by all tested sage extracts. These results permit to propose these extracts as new source of safe natural antimicrobials

Référents culturels dans les énoncés parémiques saoudiens et algériens

Saudi and Algerian proverbs can be an inviting topic for research on paremiology. Their study will shed the light on the social, cultural and linguistic phenomena which are at the origin of statements generally attributed to the popular voice, nourished by human experience, sometimes characterized by humor, or irony and critic. In the present research, we will focus on the cultural specificities of proverbs scrutinized through the linguistic theory. The analysis will therefore be contrastive as these proverbs are paremics collected from two distant horizons (Algeria and Saudi Arabia). The cultural proximity of the two Arab-Muslim countries can sometimes reveal equivalences, but proximity does not always mean identity; differences will highlight specificities

The Translation of Najdi Advice Proverbs into English: Alsudais’s A Selection of Najdi Arabic Proverbs (1993)

This article analyses the translation of advice proverbs in Muhammad Alsudais’s A Selection of Najdi Arabic Proverbs (1993) to identify, in the first place, the author’s strategies in rendering the various features of these highly stylized forms of Najd’s folk culture and ancestral wisdom. The analysis targets also the selected proverbs’ literary features to determine to which extent they are domesticated or foreignized in the target texts. The results show that two main strategies are followed by the translator to convey the meaning of his ethnographic material: literalness and paraphrase, with the effect of foreignizing most of their meaning. However, though literal translation strategy allows the transfer to the target language most of the images embedded in Najdi proverbs, paraphrase obliterates most of the markers that define their phonic identity. This result points not only to a poetic limitation in the literal and paraphrase uses of translation, but also to an aporia in the foreignization strategy advocated by Antoine Berman and Lawrence Venuti

Kinetic and Compositional Study of Phenolic Extraction from Olive Leaves (var.Serrana) by Using Power Ultrasound

[EN] Power ultrasound is being used as a novel technique for process intensification. In this study, the feasibility of using power ultrasound to improve the phenolic extraction from olive leaves was approached taking both compositional and kinetic issues into account and also determining the influence of the main process parameters (the electric power supplied, emitter surface and temperature). For this purpose, the extraction kinetics were monitored by measuring the total phenolic content and antioxidant capacity and mathematically described by Naik's model, and HPLC DAD/MS MS was used to identify and quantify the main polyphenols. The electric power supplied and the emitter surface greatly affected the effective ultrasonic power applied to the medium, and hence the extraction rate. However, the influence of temperature on ultrasound assisted extraction was not clear. Compared with conventional extraction, ultrasound assisted extraction reduced the extraction time from 24 h to 15 min and did not modify the extract composition. Industrial relevance: Olive crop produces a significant quantity of byproducts (leaves, branches, solid and liquid wastes), coming from the tree pruning, fruit harvest and oil production, which are rich in phenolic compounds with bioactive properties. The extraction of the bioactive compounds could be an interesting option with which to increase the value of these byproducts, as it requires efficient extraction techniques in order to reduce processing costs and improve productivity. In this sense, ultrasound assisted extraction is considered a novel technique used as ameans of intensifying a slow process, such as the leaching of polyphenols fromvegetablematrices. In order to further address the industrial applications of ultrasound assisted extraction, a kinetic study should be carried out determining both the effective energy introduced into the medium, as well as its influence on the extract quality.The authors thank the Generalitat Valenciana (PROMETEO/2010/062 and PROMETEO/2012/007) for its financial support. M. H. Ahmad Qasem was the recipient of a fellowship from Ministerio de Educacion, Cultura y Deporte of Spain (Programa de Formacion de Profesorado Universitario del Programa Nacional de Formacion de Recursos Humanos de Investigacion).Ahmad-Qasem Mateo, MH.; Canovas, J.; Barrajon-Catalan, E.; Micol, V.; Cárcel Carrión, JA.; García Pérez, JV. (2013). Kinetic and Compositional Study of Phenolic Extraction from Olive Leaves (var.Serrana) by Using Power Ultrasound. Innovative Food Science and Emerging Technologies. (17):120-129. https://doi.org/10.1016/j.ifset.2012.11.008S1201291

Le fonctionnement des mécanismes discursifs dans le corpus présidentiel algérien de 1999 à 2006

This contribution aims to identify and analyze the discursive mechanisms that structure the Algerian presidential corpus from 1999 to 2006, investing in text analysis computer. The corpus presidential investing in three components, which do and make the structure of discourse: ethos, pathos, and logos. These elements form the unit of argumentative discourse. The logos triggers a process that draws on reason and logic, pathos or emotional argument, affects the sensitivity of the audience for a spontaneous adhesion, while the ethos is the involvement of self in discourse a sign of commitment, taken as an argument to justify actions and attitudes.Cette contribution a pour objectif de repérer et d�analyser les mécanismes discursifs qui structurent le corpus présidentiel algérien de 1999 à 2006, en investissant dans l�analyse des textes assistée par ordinateur. Le corpus présidentiel investit dans trois composants, qui le font et qui le structurent : ethos, pathos, et logos. Ces éléments forment l�appareil argumentatif de ce discours. Le logos déclenche un processus qui puise dans la raison et la logique, le pathos ou argument par émotion, agit sur la sensibilité de l�auditoire, pour une adhésion spontanée, tandis que l�ethos constitue l�implication de soi dans le discours, un signe d�engagement, pris comme argument pour justifier des actions et des attitudes

Supercritical fractionation of rosemary extracts to improve the antioxidant activity

A supercritical CO 2 pilot plant was employed to extract rosemary (Rosmarinus officinalis L.) leaves and to thoroughly study the effect of time on the yield, composition and antioxidant activity of the different fractions produced. Six extraction assays were carried out, varying the fractionation procedure using a two-stage depressurization system coupled to the extractor vessel. The concentration of the main antioxidant compound in rosemary, i.e. carnosic acid, and the DPPH test were employed to evaluate the antioxidant power of the different fractions obtained. The goal was to develop a new fractionation scheme comprising two different periods of time, in which exhaustive extraction of the essential oil from the plant matrix was achieved while recovery of the antioxidant compounds was maximized.This work has been financed by project AGL2010-21565 (subprogram ALI) and project INNSAMED IPT-300000-2010-34 (subprogram INNPACTO) from the Ministerio de Ciencia e Innovación (Spain).Peer Reviewe