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Bentonite is used in pharmacology and cosmetology for different applications, the chemical and mineralogical composition and characteristics of these materials are so important. Therefore, the aim of this work is to evaluate the suitability of application of Maghnia Bentonite (clay from Algeria) through different tests. Initially, it was performed the characterization by Xray Diffraction (XRD), X-ray fluorescence spectroscopy (XRF), Swelling volum, Gel Formation, CEC and Surface area. The microbial content of natural bentonite and the activated one with 4% of Na2CO3 labelled (M4) are verified. The suspensions were characterized through tests of sedimentation rate, swelling volum and pH determination. The physical-chemical characterization of M4 indicated compatible characteristics with those of clean clay; it was observed smectite and quartz reflections as crystalline phases and in terms of chemical composition the major presence of Montmorillonite was verified. The microbiological evaluation showed that microbial content of M4 Bentonite presents acceptable limits, according to the Pharmacopeas. The pH of the sample M0 was close to neutral (7.75 ± 0.05), while the pH of the sample M4 (9.2). The results showed a possible application of M4 in pharmaceutical products. [ABSTRACT FROM AUTHOR]

Background: Obesity is considered to be one of the major risk factor for emerging noncommunicable diseases. The objective of this study was to estimate the prevalence of overweight and obesity among Algerian population, and to investigate socio-demographic behavioural and clinical factors, related with these conditions. Methods: This is a descriptive cross-sectional study involving individuals aged 18 years old and above. Analysis based on data from the national survey to chronic disease risk factor surveillance conducted in Algeria between 2016 and 2017 according to the World Health Organization STEPwise approach. Continuous variables were compared between groups using the Student’s t test, while differences in prevalence between underweight, normal weight, overweight and obesity were assessed using the chi-square test. We also looked at the potential associations between independent factors and the prevalence of overweight and obesity using a logistic regression model. Results: The prevalence rates of overweight and obesity were 35.3% (95% CI: 34.1–36.6%) and 24.7% (95% CI: 23.7–25.7%) respectively. Overweight was more common in males than to females while obesity was significantly higher among females compared to males. According to multivariate logistic regression analysis, age, separated or divorced category of marital status, raised blood Pressure and raised total cholesterol were the strongest risk factors of overweight and obesity. Conclusions: Overweight and obesity are highly prevalent and epidemic in the whole Algerian population. Quantification and monitoring of their risk factors is urgently needed to plan effective public health intervention measures, in order to reduce this burden and prevent other non-communicable diseases, especially cardiovascular disorders. [ABSTRACT FROM AUTHOR]

In this article we studied the effect of time and mass concentration on the viscoelastic behavior of a clay and slip used in the manufacture of ceramics from CERAMIR Algeria. The generalized model of Kelvin-Voigt is successfully applied to fit the creep and recovery data and to analyse the viscoelastic properties of clay and slip. The increase of time of creep-recovery shows a slow increase in Newtonian viscosity corresponding to the steady-state and instantaneous and delayed elastic compliance. On the other hand, the increase in the mass concentration of clay causes a rapid increase in the Newtonian viscosity corresponding to the steady-state and a decrease in instantaneous and delayed elastic compliance. [ABSTRACT FROM AUTHOR]

Volcanic clay from Aïn Ouarka south west of Algeria (CA) was used to remove malachite green (MG). This material was purified and sodified (CA‐Na+). They were characterized by different analysis techniques such as BET, SEM, XRD, ATG‐ATD, FTIR, and the cation‐exchange capacity (CEC). Batch adsorption tests were performed to examine the effect of several parameters such as contact time, pH of solutions, initial concentration, and temperature. The present study is the first to be carried out hitherto regarding natural clay, where the obtained results show that the clay contains two phases, Sericite 2M1 and Clinochlore, with good crystalline, very compact and layered structure. The adsorption of MG dye reached its maximum at pH close to 6. Kinetic and isothermal experiments were studied to establish the equilibrium time and adsorption capacity of the two clays. Two kinetic models; the pseudo‐first and pseudo‐second order models were used. Two isothermal equations, Freundlich and Langmuir were applied for the modeling of adsorption isotherms by the linear method. The maximum adsorption capacities calculated from Langmuir equation of CA and CA‐Na+ are 166 and 126 mg g−1, respectively. A significant variation of temperature demonstrated that the adsorption phenomenon was an endothermic process. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13152, 2019 [ABSTRACT FROM AUTHOR]