Search results for: Soumendu Monia

Authors: Soumendu Monia, Vaibhav Jain, Hrishikesh Jugade, Manashi Adhikary, Goutam Mukhopadhyay

Abstract:

'Rolled in scale' (RIS) and 'Rolled in Scum' (RISc) are two superficial surface defects on cold rolled and annealed steel sheets which affect the aesthetics of surface and thereby that of the end-product. Both the defects are believed to be originating from distinctly different sources having different mechanisms of formation. However, due to their similar physical appearance, RIS and RISc are generally confused with each other and hence attaining the exact root cause for elimination of the defect becomes difficult. RIS appears irregular in shape, sometimes scattered, and always oriented in rolling direction. RISc is generally oval shaped, having identifiable pointed edges and mostly oriented in rolling direction. Visually, RIS appears to be greyish in colour whereas RISc is whitish in colour. Both the defects have quite random occurrence and do not leave any imprints on the reverse-side of the sheet. In the current study, an attempt has been made to differentiate these two similar looking surface defects using various metallographic and characterization techniques. Systematic experiments have been carried out to identify possible mechanisms of formation of these defects. Detailed characterization revealed basic differences between RIS and RISc with respect to their surface morphology. To summarize, RIS was observed as a residue of an otherwise under-pickled scale patch on surface, after it has been subjected to cold rolling and annealing in a batch/continuous furnace. Whereas RISc was found to be a localized rubbing of the surface, at the time of cold rolling itself, resulting in a rough surface texture.

Keywords: annealing, rolled in scale, rolled in scum, skin panel

Procedia PDF Downloads 139

Authors: Monia Hassan Abdulrahman

Abstract:

Resource-based view is built on many theories in addition to diverse perspectives, we extend this view placing emphasis on human resources addressing the tools required to sustain competitive advantage. Highlighting on several theories and judgments, assumptions were established to clearly reach if resource possession alone suffices for the sustainability of competitive advantage, or necessary accommodation are required for better performance. New practices were indicated in terms of resources used in firms, these practices were implemented on the human resources in particular, and results were developed in compliance to the mentioned assumptions. Such results drew attention to the significance of practices that provide enhancement of human resources that have a core responsibility of maintaining resource-based view for an organization to lead the way to gaining competitive advantage.

Keywords: competitive advantage, resource based value, human resources, strategic management

Procedia PDF Downloads 363

Authors: Monia Hejaiej

Abstract:

The fable has lent itself to memorable imitations and reinventions. The writing of fables, in prose and verse, was widely cultivated not only in pre-Islamic Arabia but also in the middle ages, reaching its culmination with the Egyptian poet and man of letters Ahmad Shawqī (1989-1932), who revived the ancient tradition, a relatively minor and unexploited genre in the modern era, and re-wrote rimed fables with an Arab Islamic flavor, articulating a set of modern ethico-political concepts and sensibilities such as a belief in good judgment in governance, individual liberty, democracy, a sense of the brotherhood of man and justice. This essay aims to restore the 20th Century poet to his rightful place in the international pantheon of literary achievement, and offers an examination of the Arabian fabulist tradition as it appears in Arabic literature, and a treatment of this genre re-visiting a few representative samples of Ahmad Shawqī collection of fables and their implications for contemporary politics in the Middle East.

Keywords: fable, politcs, governace, democracy, ethics of care

Procedia PDF Downloads 642

Authors: Sabria Barka, Imen Gdara, Zouhour Ouanès, Samia Mouelhi, Monia El Bour, Amel Hamza-Chaffai

Abstract:

Because dams are large semi-closed reservoirs of pollutants originating from numerous anthropogenic activities, they represent a threat to aquatic life and they should be monitored. The present work aims to use freshwater zooplankton (Copepods and Cladocerans) in order to evaluate the environmental health status of Bir M'cherga dam in Tunisia. Animals were collected in situ monthly between October and August. Genotoxicity (micronucleus test), neurotoxicity (acetylcholinesterase, AChE) and oxidative stress (catalase, CAT and malondialdehyde, MDA) biomarkers were analyzed in zooplankton. High frequencies of micronucleus were observed in zooplankton cells during summer. AChE activities were inhibited during early winter and summer. CAT and MDA biomarker levels showed high seasonal variability, suggesting that animals are permanently exposed to multiple oxidative stress. The results of this study suggest that the Bir Mcherga dam is subject to continuous multi-origin stress, probably amplified by abiotic parameters. It is then recommended to urgently monitor freshwater environments in Tunisia, especially those used for irrigation and consumption.

Keywords: Biomonitoring, Bir Mcherga Dam, cladocerans, copepods, freshwater zooplankton, genotoxicity, neurotoxicity, oxidative stress, Tunisia

Procedia PDF Downloads 38

Authors: Atitallah Sofien, Bouyahia Olfa, Mohsen S., Boussetta Khadija, Khemiri Monia, Fitouri Zohra, Boukthir Samir

Abstract:

Introduction: Megaloblastic anemia (MA) is rare in children. The diversity of its etiologies can lead to misdiagnosis and may, therefore, delay the treatment. The aim of this study was to describe the epidemiological and etiological characteristics of children followed for MA at the Tunis children's hospital. Methodology: This is a retrospective study over a period of 25 years of all cases of MA in children in the Children's Hospital of Tunis. The diagnosis of MA was confirmed by myelogram in all patients. Results: We collected 29 observations, with an incidence of 1.2 cases/year and a sex ratio of 1. Sixty percent of the children were aged between 3 months and 2 years. The consultation time was between 15 and 30 days in a third of the patients. The clinical examination showed hypotrophy in 13% of cases, hepatosplenomegaly in 6% of cases, neurological or neurosensory damage in 23% of cases, and cardiac damage in 10% of children. MA was associated with thrombocytopenia in 65% of cases and leukoneutropenia in 24% of cases. One in 5 children had pancytopenia. The etiologies were mainly thiamine deficiency, Immerslund disease (20%), nutritional deficiency (13%), and Biermer anemia (13%). One of the patients presented an MA revealing visceral leishmaniasis. The outcome under vitamin B12, the dose of which was adapted to each etiology, was favorable for all patients. Conclusion: MA is rare in children with multiple etiologies that are mainly dominated by hereditary conditions and nutritional deficiencies, mainly in vitamin B12. The association with visceral leishmaniasis seems to be a particularity in our country not reported in the literature.

Keywords: megaloblastic anemia, children, vitamin B12, anemia

Procedia PDF Downloads 29

Authors: Anis Belhaj Mohamed, Moncef Saidi, Mohamed Soussi, Ibrahim Bouazizi, Monia Ben Jrad

Abstract:

This paper summarizes the results of Rock-Eval pyrolysis and biomarker data of shale samples collected from the Ordovician age (Llanvirnian-Llandeilian) (Azzel Formation) in the Chotts basin southern part of Tunisia. The results are supported by analysis of cutting samples from wells. The Azzel shales has poor to moderate, occasionally good, potential for sourcing oil and gas with Total Organic Carbon (TOC) content varying from 0.80 to 4.49 % and petroleum potential (PP) values varying between 0.68 to 9.20 Kg of HC/t rock in Baguel and Alaguia wells. However, the Azzel Formation show poor to fair TOC and PP in Elfranig and HajBrahim wells not exceeding 1.10% and 1.05 kg HC/t of rock respectively. The Hydrogen Index (HI) and the Oxygen Index (OI) values of 95–165 mg S2/g TOC and of 33–108 mg CO2/g rock relatively show that the Ordovician shales exhibit type II Kerogen that reached the main oil window stage and that the organic matter was bad preserved, Tmax values of 435 – 448°C indicate the organic matter is mature. The biomarker features of the extract samples are characterized by high proportion of tricyclic terpanes that are dominated by C23 and C21 tricyclic terpanes. The hopanes fraction is dominated by C29 and C30 hopanes. The Ordovician shales show a predominance of C27 over C29 steranes (C27/C29>1) and relatively high proportions of diasteranes supporting the shaly character of the source rock.

Keywords: biomarkers, organic geochemistry, ordovician source rock, diasteranes

Procedia PDF Downloads 465

Authors: Wala Abou Saoud, Aymen Amine Assadi, Monia Guiza, Abdelkrim Bouzaza, Wael Aboussaoud, Abdelmottaleb Ouederni, Dominique Wolbert

Abstract:

Volatile organic compounds (VOCs) constitute one of the most important families of chemicals involved in atmospheric pollution, causing damage to the environment and human health, and need, consequently, to be eliminated. Among the promising technologies, dielectric barrier discharge (DBD) plasma - photocatalysis coupling reveals very interesting prospects in terms of process synergy of compounds mineralization’s, with low energy consumption. In this study, the removal of organic compounds such butyraldehyde (BUTY) and dimethyl disulfide (DMDS) (exhaust gasses from animal quartering centers.) in air mixture using DBD plasma coupled with photocatalysis was tested, in order to determine whether or not synergy effect was present. The removal efficiency of these pollutants, a selectivity of CO₂ and CO, and byproducts formation such as ozone formation were investigated in order to evaluate the performance of the combined process. For this purpose, a series of experiments were carried out in a continuous reactor. Many operating parameters were also investigated such as the specific energy of discharge, the inlet concentration of pollutant and the flowrate. It appears from this study that, the performance of the process has enhanced and a synergetic effect is observed. In fact, we note an enhancement of 10 % on removal efficiency. It is interesting to note that the combined system leads to better CO₂ selectivity than for plasma. Consequently, intermediates by-products have been reduced due to various other species (O•, N, OH•, O₂•-, O₃, NO₂, NOx, etc.). Additionally, the behavior of combining DBD plasma and photocatalysis has shown that the ozone can be easily also decomposed in presence of photocatalyst.

Keywords: combined process, DBD plasma, photocatalysis, pilot scale, synergetic effect, VOCs

Procedia PDF Downloads 297