KEMIN WANG, LIFEI HE

Journal of Polymer Materials, Vol.36, No.3, pp. 253-260, 2019, DOI:10.32381/JPM.2019.36.03.5

Abstract This study proposes a simple approach for the fabrication of microspherical catalysts with a hierarchical porous structure. The cross-linked porous microspheres with catalytic ability were prepared directly from small-molecular monomers via low-temperature phase-separation photopolymerization of water/oil suspension. The morphology, pore size, chemical structure, and thermal stability of the obtained porous microspheres were characterized by SEM, Mercury Intrusion Porosimetry, FTIR, and TGA. The porous microspheres directly served as an acid catalyst for the condensation reaction of benzaldehyde and ethylene glycol, which exhibited superior catalytic activity and recyclability. The results indicated that such porous microspheres have great potential in the application of… More >

DIPESHKUMAR D. KACHHADIYA, Z.V.P. MURTHY^*

Journal of Polymer Materials, Vol.38, No.1-2, pp. 49-61, 2021, DOI:10.32381/JPM.2021.38.1-2.5

Abstract The conventional process for methanol-water separation like distillation consumes about 60 % of total energy. As an alternative, researchers have developed a membrane-based separation process for alcohol-water mixtures separation. However, there is a big challenge for researches to separate alcohol-water aqueous mixtures using a polymeric membrane because of swelling. In the present work, the aim is to separate methanol from water by pervaporation using polymeric membranes made up of polyvinylidenefluroide (PVDF) and polyethylene glycol (PEG200) modified PVDF membranes. The membranes were characterized by thermogravimetry analysis (TGA), field emission scanning electron microscopy (FE-SEM), and Fourier-transform infrared spectroscopy (FTIR). A study on… More >

VRINDA GOEL¹, RUCHIKA TANWAR¹, AJOY KUMAR SAIKIA², UTTAM KUMAR MANDAL^1,*

Journal of Polymer Materials, Vol.39, No.3-4, pp. 283-305, 2022, DOI:10.32381/JPM.2022.39.3-4.8

Abstract The commercially available Polysulfone (PSF) membrane surface was modified by solution polymerization of aniline using different oxidation catalysts i.e., FeCl₃, CuCl₂, and APS. Modified membranes were then characterized with respect to physio-chemical properties like surface chemistry, porosity, wettability, surface roughness, morphology, etc. It was observed that the hydrophilicity/ wettability of membranes was increased upon surface modification by polyaniline which again depended on the nature of the oxidation catalyst used. Membranes developed using FeCl₃ and CuCl₂ as oxidants exhibit improved permeation, protein rejection, and antifouling properties, whereas decrement was observed in modified membrane performance using APS as an oxidant. Among all… More >

Chen Fang^*, Milnes David, Anita Rogacs, Kenneth Goodson

Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-11, 2010, DOI:10.5098/hmt.v1.1.3002

Abstract Vapor-venting microchannel heat exchangers are promising because they address the problems of high pressure drop, flow instability, and local dryout that are common in conventional two-phase microchannel heat sinks. We present a 3D numerical simulation of the vapor-venting process in a rectangular microchannel bounded on one side by a hydrophobic porous membrane for phase-separation. The simulation is based on the volume of fluid (VOF) method together with models for interphase mass transfer and capillary force. Simulation shows the vapor-venting mechanism can effectively mitigate the vapor accumulation issue, reduce the pressure drop, and suppress the local dry-out in the microchannel. Pressure… More >

Georg F. Dietze^†, Reinhold Kneer

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-14, 2011, DOI:10.5098/hmt.v2.3.3001

Abstract Despite the use of liquid films in a wide variety of technical applications involving heat and mass transfer (e.g. nuclear reactors, cooling towers and gas turbines), where they often play an important role, the underlying momentum and heat transport processes within these thin liquid layers remain to be fully elucidated. In particular, this applies to the influence that surface waves, developing due to the film’s natural instability, exert on the mentioned processes. In this context, it has been suggested by several experimental and numerical observations that momentum and heat transfer in the capillary wave region (which precedes large surface waves)… More >

Muhd Hadi Iskandar Abd Razak^*, Motoki Tsuda, Yukio Hayakawa, Shinji Kambara

Energy Engineering, Vol.121, No.2, pp. 259-272, 2024, DOI:10.32604/ee.2023.043615

Abstract Hydrogen is an alternative energy source that has the potential to replace fossil fuels. One of the hydrogen applications is as a material for Polymer Electrolyte Membrane Fuel Cells (PEMFC) in fuel cell vehicles. High-purity hydrogen can be obtained using a hydrogen separation membrane to prevent unwanted contaminants from potentially harming the PEMFC components. In this study, we fabricated a plasma membrane reactor and investigated the permeation performance of a hydrogen separation membrane in a plasma membrane reactor utilizing atmospheric pressure plasma. The result showed the hydrogen permeation rate increasing with time as reactor temperature is increased through joule heating.… More >

Yongchun Liu^1,*, Ni Qiao², Yanli Yang³, Yanchun Li¹, Chunxiao He¹, Siyang Wang¹, Chengcheng Liu¹, Ruixia Lei¹, Wang Li⁴, Wenwen Gao⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 383-400, 2024, DOI:10.32604/fdmp.2023.041928

Abstract A silylated melamine sponge (SMS) was prepared by two simple steps, namely, immersion and dehydration of a melamine sponge coated with methyltrichlorosilane. The silylated structure of SMS was characterized by FT-IR (Fourier-transform infrared) spectroscopy, SEM (Scanning electron microscopy) and in terms of water contact angles. Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophotometry. The experimental results have shown that oligomeric silanol covalently bonds by Si−N onto the surface of melamine sponge skeletons. SMS has shown superhydrophobicity with a water contact angle exceeding 150° ± 1°, a better separation efficiency with regard to diesel oil (by 99.31% (wt/wt%)… More >

Seyed Ehsan Rafiee^*, M. M. Sadeghiazad

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-15, 2016, DOI:10.5098/hmt.7.13

Abstract The aim of this investigation is study on separation phenomenon inside a special vortex tube affected by structural and physical factors including; throttle diameter, nozzle number and injection pressure as well as the parametric optimization based on separation efficiency using experimental and 3D-CFD methods. The results show that convergent VT with Dth=5.5mm provides 30.01% and 20.04% higher cooling and heating effectiveness compared to basic model. As another result, the higher injection pressure, the higher cooling effectiveness. The cooling effectiveness improves (16.86%) with increase in slot number up to N=4, then decreases. The maximum disagreement between experimental and predicted values is… More >

Dong Li^1,*, Yonggang Zheng¹, Hongwu Zhang¹, Hongfei Ye¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09714

Abstract The family of 2D transition-metal oxides and dichalcogenides with 1H phase (1H-MX₂) has sparked great interest from the perspective of basic physics and applied science. Interestingly, their performances could be further regulated and improved through strain engineering. Effective regulation is founded on a wellunderstood mechanical performance, however, the large number of 1H-MX₂ materials has not yet been revealed. Here, a general theoretical model is constructed based on the molecular mechanics, which provides an effective and rapid analytical algorithm for evaluating the mechanical properties of the entire family of 1H-MX₂. The validity of the constructed model is verified by molecular dynamics… More >

Zhaolin Chen^1,*, Xiaohui Wei¹, Tianhang Xiao¹, Ning Qin²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09976

Abstract A computational study has been conducted on various airfoils to simulate flows at low Reynolds numbers 17,000 and 21,000 with Mach number changes from 0.25 to 0.85 to provide understanding and guidance for Mars rotory wing designs. The computational fluid dynamics tool used in this study is a Reynolds-averaged Navier–Stokes solver with a transition model (k-ω SST γ-Reθ). The airfoils investigated in this study include NACA airfoils (4, 5, and 6% camber), UltraThin airfoils, and thin cambered plates (3% camber, but various maximum camber locations). Airfoils were examined for lift and drag performance as well as surface pressure and flow… More >