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Illumination of biosorption of Allura Red on Rhus coriaria L. (sumac) plant: equilibrium, kinetic, thermodynamic, and density functional theory–based analyses
No full textIn the present paper, the biosorption capability of Rhus coriaria L. (sumac) plant for the effective removal of Allura Red (AR) dye from wastewater was tested in the light of theoretical and experimental tools. The reactive functional groups in the structure of the studied biosorbent and the surface morphology of the mentioned biosorbent were highlighted with the help of FTIR spectrophotometer, SEM (scanning electron microscopy), and EDX (energy-dispersive X-ray analysis). The effect of important parameters such as pH, time, adsorbent mass, and temperature on the biosorption process was checked and discussed in detail. pH 2 was determined as the optimum value for the highest biosorption. Maximum effectiveness was reached at a biosorbent mass of 200 mg. The biosorption process adhered to the Langmuir isotherm and PSO kinetic models, and the process was determined to have a spontaneous and exothermic nature. Through the recovery experiments, it was noted that the studied plant retained approximately 30% of its biosorption capacity after three cycles. To prove the power of the interaction between Allura Red dye and dominant components of Rhus coriaria L. (sumac), density functional theory calculations were performed. Theoretically obtained conceptual DFT-based descriptors, the comments made within the framework of popular electronic structure rules, and calculated adsorption energies were in good agreement with the experimentally obtained data. As a result, it was reported that Rhus coriaria L. can be used as an effective and useful biosorbent for the removal of AR from wastewater
Characteristics of harmonic and anharmonic spherical quantum dots modulated by structural parameters and hydrogenic impurity
No full textIn the present work, we explore the optical peculiarities of GaAs quantum dot (QD) built on harmonic and anharmonic confining potentials. Numerical results are made within parabolic band and effective mass (EM) theories. Using the well-known finite difference technique, we have computed the lowest energy levels and their probabilities. Afterwards, we have work out the amplitudes of the optical absorption coefficients (OACs) and discussed the influence of the hydrogenic impurity and confining potential’s parameters on the red or blue shifts presented by the system. Our findings prove that the optical and electronic characteristics of the structure we emphasis on can be modulated to attain a suitable optical absorption to specific needs or purposes by varying the potential’s parameters and the existence or absence of the hydrogenic impurity. The change of the potential’s parameters can generate two shapes of confining potentials (Harmonic and Anharmonic) which gives us more flexibility to tune and control the desired energy levels and per consequent to adjust and select the suitable OAC between the two lowest energy states (ground (1s) and first excited (1p))
Effectiveness of a Cognitive Behavioral Group Therapy Program for Obesity: A Pre-post and 6-Month Follow-up Results
No full textInterest in psychological interventions for obesity treatment has been increasing. This study examines the effectiveness of cognitive behavioral group therapy (CBGT) alongside standard diet therapy in reducing body mass ındex (BMI). Additionally, it investigates the predictive role of emotion regulation and problem-solving sessions integrated into the CBGT protocol. Participants with a BMI of 30 or higher were assigned to diet-only, diet + CBGT, or control groups. Measurements were taken at baseline, post-therapy, and six months later. Results showed significant BMI reductions in diet and diet + CBGT groups, with no changes in the control group. Six months later, the diet + CBGT group maintained their BMI reductions, unlike the diet-only group. Regression analysis indicated that positive emotion regulation predicted BMI changes, while negative regulation and problem-solving did not. These findings highlight the role of CBGT in obesity treatment and suggest that incorporating sessions aimed to improve positive emotion regulation skills would be beneficial
