Ehsan Samimi-Sohrforozani

In this study, the performance of a sorption-enhanced membrane reactor (SEMR) was examined using a Pd-Ag membrane during ethanol steam reforming (ESR). During this study, simultaneous ESR and CO2 adsorption concept was adopted and computational fluids dynamic (CFD) method (two-dimensional model) was developed to evaluate the SEMR performance during ESR reaction. The employed CFD model for the present study provided information about the molar fractions and pressures of components to analyze driving forces under unsteady state condition. Regarding validation, the experimental data related to the membrane reactor (MR) during ESR reaction showed good agreement with modeling outcomes and the application of adsorption reaction improved MR performance. The SEMR performance was investigated after model validation, and during this step, SEMR and MR were compared. Moreover, the effects of main operating parameters, such as gas hour space velocity (GHSV), reaction pressure, and temperature, were studied to compare the SEMR and MR performance during C2H5OH conversion and hydrogen recovery. CFD modeling results showed that SEMR had better performance and increased the ethanol conversion about 20% (SEMR: 70% and MR: 59%) by temperature enhancement at low pressures compared with the conventional membrane reactor. The relative error between numerical and experimental data obtained was 3% in this study.

Nanotechnology is making significant transformation to our world, especially in healthcare and the treatment of diseases. It is widely used in different medical applications, such as in treatment and detection. Targeting diseased cell with nanomedicines is one of the numerous applications of nanotechnology. Targeted drug delivery systems for delivering various types of drugs to specific sites are such a dynamic area in pharmaceutical biotechnology and nanotechnology. Compared to conventional drugs, nanomedicines have a higher absorption and bioavailability rate, improving efficacy and minimizing side effects. There are several drug delivery systems including metallic nanoparticles, polymers, liposomes, and microspheres, but one of the most important is the niosomes, which are produced by nonionic surfactants. Because of the amphiphilic nature and structure, hydrophilic or hydrophobic drugs can be loaded into niosome structures. Other compounds, including cholesterol, can also be applied to the niosomes' backbone to rigidize the structure. Several variables such as the type of surfactant in niosome production, the preparation method, and the hydration temperature can affect the structure of the niosomes. Nevertheless, in-silico design of drug delivery formulations requires molecular dynamic simulation tools, molecular docking, and ADME (absorption; distribution; excretion; metabolism) properties, which evaluate physicochemical features of formulation and ADME attitudes before synthesis, investigating the interaction between nano-carriers and specific targets. Hence, experimenting in-vitro and in-vivo is essential. In this review, the basic aspects of niosomes are described including their structure, characterization, preparation methods, optimization with in-silico tools, factors affecting their formation, and limitations.

Polyacrylonitrile (PAN) fibers with unique properties are becoming increasingly important as precursors for the fabrication of carbon fibers. Here, we suggest the preparation of porous PAN composite fibers to increase the homogeneity and thermal stability of the fibers. Based on the thermodynamics of polymer solutions, the ternary phase diagram of the PAN/H₂O/Dimethylformamide (DMF) system has been modeled to introduce porosity in the fibers. Adding a conscious amount of water (4.1 wt.%) as a non-solvent to the PAN solution containing 1 wt.% of graphene oxide (GO), followed by wet spinning, has led to the preparation of porous composite fibers with high thermal stability and unique physicochemical properties. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) results elucidate that PAN/GO/H₂O porous composite fibers have a higher thermal decomposition temperature, increased residual weight, reduced heat release rate, and higher crystallinity in comparison with the pristine PAN fibers, being a promising precursor for the development of high-performance carbon fibers. The results show a promising application window of the synthesized PAN fibers in electronic and electrochemical devices.