Publications by authors named "V D Sandu"

Membrane technology is considered an innovative and promising approach due to its flexibility and low energy consumption. In this work, a comprehensive 3D-CFD model of the Hollow-Fiber Membrane Contactor (HFMC) system for CO capture into aqueous MEA solution, considering a counter-current fluid flow, was developed and validated with experimental data. Two different flow arrangements were considered for the gas mixture and liquid solution inside the HFMC module.

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This study aims to explore more sustainable ammonia production routes for urea and ammonium nitrate fertilizers to support the rising global food demand and help achieve the Net Zero Emissions scenario by 2050. The research uses process modelling tools and Life Cycle Assessment methodology to evaluate the technical and environmental performance of green ammonia production compared to blue ammonia production, both pathways coupled with urea and ammonium nitrate production processes. The blue ammonia scenario uses steam methane reforming for H production, while the sustainable approach scenarios consider water electrolysis with renewable resources (i.

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Sesquipedalian mud and burnt bricks (second to third century AD) were excavated from the Roman city of Romula located in the Lower Danube Region (Olt county, Romania). Along with local soils, bricks are investigated by petrographic analysis, X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), electron microscopy (SEM/EDX), X-ray microtomography (XRT), thermal analysis (DTA-TG), Mӧssbauer spectroscopy, magnetometry, colorimetry, and mechanical properties assessment. The results correlate well with each other, being useful for conservation/restoration purposes and as reference data for other ceramic materials.

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An analysis of the field dependence of the pinning force in different, high density sintered samples of MgB is presented. The samples were chosen to be representative for pure MgB, MgB with additives, and partially oriented massive samples. In some cases, the curves of pinning force versus magnetic field of the selected samples present peculiar profiles and application of the typical scaling procedures fails.

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Hybrid bionanocomposite coating systems (HBCSs) are green polymer materials consisting of an interface between a coating matrix and nanoparticles. The coating matrix was prepared by using a nonisocyanate poly(hydroxyl urethane) (NIPHU) prepolymer crosslinked via 1,3-diaminopropane and epoxidized oil. TEMPO-oxidized cellulose nanoparticles (TARC) were prepared from microcrystalline cellulose, and (3-aminopropyl)trimethoxysilane (APTMS)-coated ZnO nanoparticles (APTMS-ZnO) and their suspensions were synthesized separately.

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