Nabila Eka Yuningsih, Latifa Ariani, Suprapto Suprapto, Ita Ulfin, Harmami Harmami, Hendro Juwono, Yatim Lailun Ni’mah^*

Journal of Renewable Materials, Vol.12, No.5, pp. 981-992, 2024, DOI:10.32604/jrm.2024.049109

Abstract In this research, activated carbon from mangosteen peel has been synthesized using sulfuric acid as an activator. The adsorption performance of the activated carbon was optimized using malachite green dye as absorbate. Malachite green dye waste is a toxic and non-biodegradable material that damages the environment. Optimization of adsorption processes was carried out using Response Surface Methodology (RSM) with a Box-Behnken Design (BBD). The synthesized activated carbon was characterized using FTIR and SEM instruments. The FTIR spectra confirmed the presence of a sulfonate group (-SOH) in the activated carbon, indicating that the activation process using… More >

Suprapto Suprapto, Putri Augista Nur Azizah, Yatim Lailun Ni’mah^*

Journal of Renewable Materials, Vol.11, No.12, pp. 4007-4023, 2023, DOI:10.32604/jrm.2023.031210

Abstract This research focuses on the effective removal of methylene blue dye using silica gel synthesized from chemical glass bottle waste as an environmentally friendly and cost-effective adsorbent. The adsorption process was optimized using Box-Behnken Design (BBD) and Response Surface Methodology (RSM) to investigate the influence of pH (6; 8 and 10), contact time (15; 30 and 45 min), adsorbent mass (30; 50 and 70 mg), and initial concentration (20; 50 and 80 mg/L) of the adsorbate on the adsorption efficiency. The BBD was conducted using Google Colaboratory software, which encompassed 27 experiments with randomly assigned… More > Graphic Abstract

Yatim Lailun Ni’mah^*, Nabila Eka Yuningsih, Suprapto Suprapto

Journal of Renewable Materials, Vol.11, No.6, pp. 2913-2924, 2023, DOI:10.32604/jrm.2023.025431

Abstract The adsorption of Pb(II) on silica gel synthesized from chemical glass bottle waste has been studied. The effect of independent variables (adsorbent dose, initial concentration of Pb(II), contact time, and pH) on the Pb(II) removal from water was evaluated and optimized using the Response Surface Methodology (RSM). Under optimized conditions (adsorbent dose: 20 mg; contact time: 30 min; initial Pb(II) concentration: 120 mg. L⁻¹ ; and pH: 8), the removal of Pb(II) was 99.77%. The adsorption equilibrium data obtained from the batch experiment were investigated using different isotherm models. The Langmuir isotherm model fits the experimental More >

C.P. Providakis¹, M.E. Voutetaki

Structural Durability & Health Monitoring, Vol.3, No.4, pp. 211-228, 2007, DOI:10.3970/sdhm.2007.003.211

Abstract Piezoceramic transducers have emerged as new tools for the health monitoring of large-scale structures due to their advantages of active sensing, low cost, quick response, availability in different shapes, and simplicity for implementations. In the present paper, a statistical metamodeling utilization of electro-mechanical (E/M) admittance approach by applying piezoelectric materials to the damage identification is investigated. A response surface metamodel is constructed by empirically fitting a model to a set of design points chosen using a Box-Behnken design of experiment (simulation) technique. This empirical fit allows polynomial models to be produced for relating damage parameter More >