THE INFLUENCE OF CHROMIUM ON THE CORROSION RESISTANCE OF TERNARY ZN–CO–CR ALLOY COATINGS DEPOSITED FROM CITRATE–SULPHATE BATH

Volume 76, Feb 2020
doi: 10.21506/j.ponte.2020.2.5
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Abstract: The present study consistsan experimentation of Zinc-Cobalt composite coatings. For this, the Chromium concentration influence was the principal object to improve the corrosionresistance of the coatings, which has been made by electroplating on steel substrates previously treated; it hasbeen studied by several characterization methodssuch as the X-ray diffraction, micro-hardness measurement and scanning electron microscopy (SEM). The protection against corrosion properties has been studied by potentiodynamic polarization measurements (Tafel) and electrochemical impedance spectroscopy (EIS) to the potential of corrosion-free. The parameters characterizingthe corrosion behaviour,can be determined from the Nyquist plots. It has been observed that the ternary Zn-Co-Cr alloy is characterized by enhanced the corrosionresistance compared to the binary Zn–Co alloys. Also, the addition of Cr in the Zn-Co increases the micro-hardness, XRD and SEM results and identifies any coatings Zn-Co-Cr alloy composition reveals that zinc phase.

Author(s): Malika diafi, Tahraoui Louiza, Badachen sarah, Gana Abderrahmane


AGRI-ENVIRONMENTAL IMPACT OF URBAN SEWAGE SLUDGE AFTER SOLAR DRYING

Volume 76, Feb 2020
doi: 10.21506/j.ponte.2020.2.6
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Abstract: Waste sludge is the main waste produced by a wastewater treatment plant. It contains a wide variety of biological organisms, of which a tiny part is pathogenic for humans. It consists of a complex mixture of mineral and organic matter. Metallic trace elements and organic micro pollutants are also found. Rich in fertilizers, sludge can be used as a substitute for chemical fertilizers. Solar drying is an ecological and economical solution for the treatment of these sludges before their recovery. The objective of this study is the experimentation of two drying processes of urban sludge from the urban sewage treatment plant of Touggourt, intended for agricultural application. The agri-environmental quality of dried sludge is estimated by the determination of physico-chemical parameters (dryness, organic material OM, pH, electrical conductivity EC, major elements, metallic trace elements MTE ...). The maximum temperatures obtained experimentally by the two solar dryers are considerable (70° C and 80° C, respectively), resulting in the minimum water content of the sludge after 12 hours of continuous drying by the first mode, a time reduced to 7 hours in the second drying mode. The results obtained after drying show that sludge from Touggourt contains on average more than 50% organic matter (dry matter basis) and is rich in nitrogen, which is a significant contribution especially to Saharan soils. Moreover, the trace metal content was below the threshold set by the regulations thus eliminating the risk of contamination.

Author(s): Sakina Khallef, Mounira Yagoubat, Djamel Mennouche, Bachir Bouchekima


PHYSICOCHEMICAL AND BIOLOGICAL CHARACTERIZATION OF ESSENTIAL OILS EXTRACTED FROM A MEDICINAL PLANT (MENTHA AQUATICA) IN THE REGION OF EL OUED

Volume 76, Feb 2020
doi: 10.21506/j.ponte.2020.2.4
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Abstract: The aim of this work is the extraction of essential oils (EOs) from Mentha aquatica by using the hydrodistillation technique and to study their biological activities including antimicrobial activity and antioxidant activity. The extraction yield obtained is 5.136%. These essential oils have a liquid aspect, white color and aromatic odor. Concerning the physical properties, we found that the pH is equal to 7.55, the refractive index is 1.339, and the miscibility with ethanol estimated at (1v/6.4v of ethanol). So our EOs are basic and soluble. Moreover, chemical analyzes shows that the acid number is 2.204, the ester number is 10.019, the iodine number is 0.158 and the saponification number is 12.21. Furthermore, the study of antioxidant activity using the DPPH method shows that the IC50 value of essential oil of Mentha aquatica. is 0.976 mg / ml and 0.007mg / ml for ascorbic acid . In order to know the efficiency of these essential oils on some pathogenic bacterial strains such as Escherichia coli ATCC 25922 and Bacillus subtilis ATCC 6633, we were found that they had a weak and limited activity against the bacteria studied.

Author(s): MAHBOUB Nasma, SLIMANI Noureddine, BENINE Romaissa, REDOUANI Kaouthar, KHELIL Aminata


EVALUATION OF AMOUNTS OF SALTS BROUGHT BY RIGH CANAL (ALGERIA): ANALYSIS OF CORRELATION AND MULTIPLE LINEAR REGRESSION

Volume 76, Feb 2020
doi: 10.21506/j.ponte.2020.2.3
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Abstract: Correlation and multiple linear regression were analyzed to modulate structural equations in order to evaluate, in 14 dispersed stations, the amounts of salts brought by Righ canal (southeastern Algeria) to the Chott Merouane during winter (October 16th to April 15th) and summer (April 16th to October 15th) seasons of 2012. In fact, these periods allowed determining the annual mean of these amounts by measuring electrical conductivity and streamflow (obtained using the gauging method by the exploration of the velocity field). Results showed that winter streamflow provided measuring range from 178 l/s to 5450 l/s. Values obtained in summer were comprised between 90 l/s and 2560 l/s while the annual means spread between 134 l/s and 3967 1/s. Winter, summer and annual electrical conductivities showed respective values of 15.02 to 17.71 mS/cm, 16 to 21.21 mS/cm and 15.51 to 19.46 mS/cm. From the statistical analysis, two regressive equations were built in each period of study that allowed assessing amounts of salts. However, model 2 fit better to data than Model 1. Therefore, the suggested method was found as a highly useful approach that simulates reality in predicting the amounts of salts and could be relevant on waterways of identical hydro-agricultural areas.

Author(s): Berrekbia Mohammed, Remini Boualem


FARMER-HERDER CONFLICT: THE POLITICS OF MEDIA DISCOURSE IN NIGERIA

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.13
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Abstract: The conflict between farming communities and herders in Nigeria has increased in the last four years. It has become a subject of discourse in various domains, including the media and body politic. The intensification of the crisis has spurred renewed scholarly attention to the other ways the conflict could be understood. The increased role of media in the crisis has been identified, but existing studies on the role of the media focus on media reportage, framing and coverage. There is relatively scare research on the politics of media discourse of the conflict, which can reveal representations of subjects and identities, subject-positions, subjectivity and power relations in the narrative of the conflict. Thus, this research analyses the politics of newspapers’ discourse of the conflict in Nigeria. The representations of the conflict cluster around five albeit overlapping themes, namely causes, victims, consequences, government’s responses and resolution strategies to the conflict. The discourse of the dispute is constructed as a security issue which embodies other forms of security viz national security, food security, the security of statehood and unity of the nations that make up the Nigerian state. The article shows that the construction of the conflict draws on the political and ideological dispositions of the papers. It argues that the link between the newspapers’ representation of the conflict and the strategies they proposed for curbing the dispute is weak. Thus, while media representations of the conflict can reveal the various contestations in the framing of the conflict in Nigeria, it might be insufficient to establish the link between discourse, identity and policy. Further, it argues that developing a sustainable strategy for the resolution of the crisis requires among other things, a national dialogue.

Author(s): Cletus Famous Nwankwo, Romanus U. Ayadiuno, Alphonsus N. Ali, Ignatius A. Madu


QUALITY OF LIFE IN WOMEN WITH BREAST CANCER, WHO PRACTICE REGULAR PHYSICAL EXERCISE: AN ANALYSIS OF PHYSIOLOGICAL AND PSYCHOLOGICAL DETERMINANTS

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.14
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Abstract: The aim of this study was to perform a descriptive analysis of the main physiological and psychological determinants of quality of life in women with breast cancer, who practice regular physical exercise, as well as examine which psychological variables predict quality of life, the support received from family members and friends, and the individual�s perceived physical condition. Our sample comprised 19 women aged between 39 and 76 years (55.83 � 9.33) who were receiving treatment for breast cancer. The following physiological parameters were measured: red blood cells, hemoglobin, hematocrit, basal glucose, triglycerides and cholesterol. Furthermore, questionnaires were completed to determine the following: support for autonomy, as perceived by family members and friends; the basic psychological needs for autonomy; competence and relatedness; the types of self-determined motivation for the practice of sports; quality of life; feelings of self-esteem, and the perceived physical condition. Our main findings revealed that women present low red blood cell counts, low hemoglobin and low hematocrit. In addition, self-esteem significantly and positively predicted physical and emotional wellbeing, support for autonomy and the perceived physical condition. In conclusion, the importance of promoting patients� self-esteem is highlighted via psychological interventions and/or the increased practice of physical activity.

Author(s): Marta Leyton Roman, Santiago Fresno Alba, Ruth Jimenez Castuera


A REVIEW OF MODELS AND TECHNIQUES USED TO GAUGE QUALITY IN HIGHER EDUCATION

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.15
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Abstract: The purpose of this paper is to examine various models and techniques used in HEIs around the world with a specific focus on four elements which are: the dimensions or areas covered in the quality evaluation, the instruments used for data collection, the targeted stakeholders, and the statistical analyses used for the data gathered. A review of high indexed publications was done and the focus of the search was on the specific elements. It was found that on average, there are five dimensions used in these studies which are mainly related to academic aspects and administrative services. The Questionnaire was the instrument used for data collection in all these models. The majority of these studies targeted one stakeholder of HEIs which is the current students. Different level of statistical tests were used in the analysis of the selected papers. These findings will be an important contribution to the field of quality of higher education with its critical focus on the methodological implementation in the review of the literature.

Author(s): Amal Al-Aamri, Rohana Jani, Yong Zulina Zubairi


A GENDER-BASED ASSESSMENT OF UTILIZATION OF PRIMARY HEALTH CARE SERVICES AND ASSOCIATED FACTORS IN PAKISTAN

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.7
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Abstract: This study aims at assessing gender-based utilization of PHC services and associated factors in Pakistan. In this cross-sectional study, data were collected from 302 participants within the catchment areas of 10 basic health units in Pishin District. The analysis showed both women (37.8%) and men (33.8%) to be low users of PHC services during the previous 6-month period. The findings indicated significant differences (P<0.05) between men and women in the predisposing, enabling and need factors that influenced their utilization of PHC services. The utilization of PHC services among men was associated with age; education; income; distance; availability of doctor; availability of medicine; continuity of care; satisfaction; and chronic illness. For women, utilization was related with age; marital status; income; usual source of care; availability of doctor; continuity of care; satisfaction; chronic illness; and health status. Gender issues were found in utilization of PHC services and associated factors. These findings suggest the need for the development of gender-sensitive strategies at the policy and service delivery levels to improve the utilization of PHC services by both men and women.

Author(s): Sanaullah Panezai, Mokbul Morshed Ahmad, Shahab E Saqib


CRITICAL APPLIED LINGUISTICS: THAI EFL UNIVERSITY LECTURERS’ DISCERNMENT

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.1
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Abstract: The study and use of language vis-à-vis the distribution of power in society is not commonly addressed. This study explores a group of Thai EFL (English as a Foreign Language) university lecturers’ standpoints on critical applied linguistics (CAL) and how this notion leads them to question their ways of teaching and undertaking research in the field. Two data collection methods are employed: a questionnaire and a focus-group interview. It is found that the conception in question appears to be unprecedented to most of the participants. Overall they rarely problematize or criticize their own pedagogical practices regarded as a constraint that needs to be solved regarding political dimensions and power relations involved in mainstream applied linguistics as in language hegemony, language policy and planning, language testing, and language rights. When it comes to conducting professional research, likewise, nearly all have a difficulty defining and determining what it is to be critical. Critical pedagogy, one of the aspects of CAL, is specifically introduced, raising the participants’ awareness of previously unquestioned practices, enabling them to unpick EFL teaching from a different angle. Concurrent with the 21st century skills needed in teaching and learning at present, CAL and criticality can pave a way for EFL teachers to look at problems in a new way and even further connect learning EFL to other subjects and disciplines.

Author(s): Sureepong Phothongsunan

A GROUP AUTHENTICATION AND DATA SECURITY SCHEME FOR SMART METERING IN SMART GRIDS

Volume 76, Jan 2020
doi: 10.21506/j.ponte.2020.1.4
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Abstract: Long-Term-Evolution (LTE) based Device-to-Device (D2D) communications in future generation networks are envisaged to become the basis for deployment of various applications and services in Smart Grids (SGs). However related privacy and security aspects are also under serious consideration espe-cially when dealing with large-scale deployment of services and applications related D2D groups. Current related algorithms cannot be applied directly to this new paradigm shift (i.e D2D communication and group formations). Using the IoT as the pillar communication subsystem for SGs, the service providers can deploy several applications and services some of which may include the acquisition and storage of personal infor-mation of individual SG users. However, the challenge will al-ways be in the strict preservation of privacy and security of their personal data and thus a necessity in eliminating such concerns. In this paper we introduce a privacy and security scheme that utilizes separate keys for group discovery / authentication and billing data communications exchange phases respectively. In order to enhance its resilience, the keys are distributed in a manner by a network of distributed key gen-erating centers (KDCs). Both data ciphering and deciphering algorithms follow the Diffie-Hellman key establishment protocol. Overall the smart meters (SMs) in a targeted SG billing section mutually authenticate as a group prior to da-ta/information exchange. In that way the scheme overall maintains low latencies because of the fewer authentication associated messages exchanges.

Author(s): Lebogang Bopape, Bakhe Nleya, Andrew Mutsvangwa, Philani Khumalo