T. Aghalya, R. Tamizharasi^*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 431-460, 2024, DOI:10.32604/cmes.2024.046635

Abstract In this study, the characteristics of heat transfer on an unsteady magnetohydrodynamic (MHD) Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were investigated. The flow was driven by the combined effects of the magnetic field, heat radiation, heat source/sink and chemical reaction. Copper oxide () and titanium oxide () are acknowledged as nanoparticle materials. The nondimensional governing equations were subjected to the Laplace transformation technique to derive closed-form solutions. Graphical representations are provided to analyze how changes in physical parameters, such as the magnetic field, heat radiation, heat source/sink and chemical reaction, affect the velocity, temperature… More >

SACHIN SINGH^a, MUKTI TYAGI^a,*, AJAY KUMAR TYAGI^a, PRAVEEN KUMAR KAICKER^a, LALIT VARSHNEY^b

Journal of Polymer Materials, Vol.36, No.4, pp. 305-321, 2019, DOI:10.32381/JPM.2019.36.04.2

Abstract Graphite is the most suitable material as dry lubricant. However, its application as a lubricant is limited with necessity of moisture vapors. Alternatively, polytetrafluoroethylene (PTFE) has an excellent lubrication property but does not have mechanical characteristics. The effect of gamma radiation doses on the lubrication behavior of graphite –PTFE (Inoflon A-408) system has been studied using (TR-TW-30L) tribotester with thrust washer attachment. Different compositions of graphite and PTFE were prepared and irradiated by gamma rays. Improved tribological properties of graphite –PTFE system showed by decrease in coefficient of friction and wear. SEM-EDX, XRD and contact angle analysis confirm fluorination of… More >

VIJAYASRI. K¹, ALKA TIWARI^1,*, C.V. CHAUDHARI²

Journal of Polymer Materials, Vol.36, No.1, pp. 53-73, 2019, DOI:10.32381/JPM.2019.36.01.5

Abstract High energy gamma radiation has been used to graft [2-(methacryloyloxyethyl) trimethylammonium chloride (MAETC) onto chitosan by radiation grafting method. Grafting yield was found to increase with the increase in radiation dose and monomer concentration. Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the grafted polymer and their morphological structure was analyzed by Scanning Electron Microscope (SEM). As(V) ions uptake capacity of the adsorbent was evaluated in different pH, contact time, temperature, adsorbent dose, and different arsenate ion concentration. The adsorption data was fitted well in the Langmuir model and various static parameters were calculated. It is stated that this… More >

RAJKUMAR SINGH RAWAT^1,2, MEENU TALWAR^1,*, RAJENDRA KUMAR DIWAN², AJAY KUMAR TYAGI¹

Journal of Polymer Materials, Vol.38, No.3-4, pp. 281-294, 2021, DOI:10.32381/JPM.2021.38.3-4.9

Abstract In the present paper,boron based diluent was synthesized and incorporated in to a Ultraviolet (UV) radiation curable epoxy coating composition comprising of phosphorus based initiator (Trimethylbenzoyl diphenyl phosphine oxide) for enhancing its flame retardant property. The boron based diluent was synthesized by thermal polymerization technique. The presence of boron and phosphorus on the coating surface was confirmed by Energy Dispersive X-Ray (EDX) and X-ray photoelectron spectroscopy (XPS) techniques and functionality was determination by Fourier Transform Infra-Red (FTIR) and proton/boron NMR spectroscopy technique. The flame retardency property of the coating composition was confirmed by determining limiting oxygen index,vertical burning test, rate… More >

SUBRATA PAL^1,2, BHUVNESHWAR RAI¹, AJAY KUMAR TYAGI¹, SUNITA RATTAN², VIRENDRA KUMAR³

Journal of Polymer Materials, Vol.39, No.1-2, pp. 55-70, 2022, DOI:10.32381/JPM.2022.39.1-2.4

Abstract The present work is focused on the study of antimicrobial and water absorption properties of the surface of grafted rayon fiber with quaternary ammonium-based salts containing 3- Acrylamidopropyl trimethyl ammonium chloride (APTAC) monomer induced by gamma radiation. Grafting was qualitatively confirmed by FTIR-ATR,TGA, SEM and by calculating grafting yield and grafting efficiency. The performance was examined for water absorbency and antibacterial efficacy (R) against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Study showed that water absorption, grafting yield and grafting efficiency increased steadily with the increase in monomer concentration and absorbed gamma irradiation dose up to a certain… More >

A. BELOUADAH¹, S. BERDOUS^1,3, D. BERDOUS², M. IZERROUKEN⁴, N. SAIDI-AMROUN¹

Journal of Polymer Materials, Vol.39, No.1-2, pp. 1-15, 2022, DOI:10.32381/JPM.2022.39.1-2.1

Abstract In this work, neutron induced structural modifications, on the biaxially-oriented polyethylene naphthalate (BOPEN) film, were studied by X-ray diffraction technique (XRD), Fourier transform infrared spectroscopy (FTIR/ATR), scanning electron microscopy (SEM) and polarized light optical microscopy (PLOM). The irradiation with neutron was carried out, under air, at room temperature. The changes of the structure, in volume and in surface were evaluated under the impact of neutron’s flux composed by thermally neutrons and fast neutrons. The X-ray technique showed the effect of the neutron flux’s fluence on the crystallinity of the BOPEN, which was also determined through the FTIR/ATR spectroscopy, traduced by… More >

S. ARULMURUGAN^a,*, N. VENKATESHWARAN^a, S. KUMAR^a, P. CHANDRASEKAR^a

Journal of Polymer Materials, Vol.40, No.1-2, pp. 83-91, 2023, DOI:10.32381/JPM.2023.40.1-2.7

Abstract In this research, the effect of UV light on the mechanical properties of jute polymer nanocomposites was evaluated. Due to the fact that photodegradation is a surface process and is confined to the degradation of the mechanical characteristics of polyester resin, this study focuses on the resin quality. Therefore, test samples comprised of fibre-reinforced polyester nanoclay composites were fabricated different weight ratios of nanoclay. They were put through UV exposure in an Ultraviolet (UV) chamber. Tensile testing samples were made in accordance with ASTMD638 and had a minimum thickness of 3 mm. Additionally, specimens for Flexural and Impact testing were… More >

Muhammad Abaid Ur Rehman^1,*, Muhammad Asif Farooq¹, Ahmed M. Hassan²

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 263-286, 2024, DOI:10.32604/fhmt.2023.044587

Abstract This paper proposes a mathematical modeling approach to examine the two-dimensional flow stagnates at over a heated stretchable sheet in a porous medium influenced by nonlinear thermal radiation, variable viscosity, and MHD. This study’s main purpose is to examine how thermal radiation and varying viscosity affect fluid flow motion. Additionally, we consider the convective boundary conditions and incorporate the gyrotactic microorganisms equation, which describes microorganism behavior in response to fluid flow. The partial differential equations (PDEs) that represent the conservation equations for mass, momentum, energy, and microorganisms are then converted into a system of coupled ordinary differential equations (ODEs) through… More >

Dewi Puspitasari¹, Diah Kusuma Pratiwi¹, Pramadhony Amran², Kaprawi Sahim^1,*

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 305-315, 2024, DOI:10.32604/fhmt.2023.041882

Abstract The natural convection from a vertical hot plate with radiation and constant flux is studied numerically to know the velocity and temperature distribution characteristics over a vertical hot plate. The governing equations of the natural convection in two-dimension are solved with the implicit finite difference method, whereas the discretized equations are solved with the iterative relaxation method. The results show that the velocity and the temperature increase along the vertical wall. The influence of the radiation parameter in the boundary layer is significant in increasing the velocity and temperature profiles. The velocity profiles increase with the increase of the radiation… More >

Dye-Zone A. Chen, Gang Chen^*

Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-6, 2010, DOI:10.5098/hmt.v1.2.3005

Abstract We present a calculation of the thermally generated electromagnetic flux propagating along the in-plane direction of a polar, thin film. The approach is based on fluctuational electrodynamics and the fluctuation-dissipation theorem. We find that for silicon carbide films between 5 nm and 100 nm thick, the thinner films transport more in-plane flux due to the long propagation length of the anti-symmetric surface phonon-polariton mode. Comparison of results obtained from the fluctuation-dissipation approach and the kinetic theory approach shows favorable agreement. More >