Investigation into the curling behavior of single jersey weft-knitted fabrics and its prediction using neural network model

This research investigates the effect of fiber, yarn, and fabric parameters on curling phenomenon of single jersey weft-knitted fabrics which is interpreted to have curling surface in both course and wale direction. Taguchi’s experimental design is used to estimate the optimum process conditions and to examine the individual effects of all controllable factors on curling one by one. The controllable factors are blending ratio of polyester to cotton fiber, yarn twist and count, fabric structure, knit density, and relaxation time. Results show that fabric structure and knit density have the most dominant effect on the fabric curling. The optimum conditions of minimum curling values were also determined. Finally, the curling surface in course and wale direction as a two features of curling phenomenon was predicted using artificial neural network which selects scale conjugate gradient learning algorithm based on process parameters of single jersey weft-knitted fabrics. Our findings confirm the good capability of artificial neural network algorithm to predict these features.     

Structure and properties of nylon-6/amino acid modified nanoclay composite fibers

Biodegradable amino acid modified nanocaly was applied to produce nylon-6/nanoclay composite fibers using melt blending and melt spinning processes. Field emission scanning electron microscopy images showed that the surface of composite fibers was uniform and free from defects. Layer spacing of modified nanoclay was increased due to the penetration of polymer molecules into clay layers. Crystallinity, γ crystalline percentage and total molecular orientation of composite fibers were higher in comparison to neat nylon-6 fibers, as revealed by WAXD and birefringence measurements. Tensile strength of composite fibers was lower when compared to neat nylon-6 fibers. This may be attributed to some aggregation of nanoclay and its weakening effect. Melting and glass transition temperature of composite fiber was decreased due to the addition of modified nanoclay, indicating the formation of γ crystals and also breaking of some hydrogen bonds between the polymer molecules and the formation of new hydrogen bonds between the modified clay and the polymer molecules.     

Ion adsorption studies of micro and nano acrylic fibers modified by ethanolamine

Micro and nano polyacrylonitrile fibers were modified to polyacrylonitrile‐monoethanolamine (PAN‐MEA) through reaction PAN with ethanolamine. The modified PAN fiber was prepared by conversion nitrile groups into hydroxyle groups using ethanolamine solution with different concentration under refluxing at 91°C. Modified raw acrylic fibers (RAF) with submicrometer diameters ranging from 120 to 300 nm were produced using electrospinning in N,N‐dimethyl formamide (DMF). The PAN‐MEA micro and nano fibers were examined as chelating material in a series of batch adsorption experiments for removal of Cu (II), Pb (II) and Ni (II) ions. The fiber structure has been investigated by different experimental techniques of characterization such as Fourier transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Also, the physical and mechanical properties has been investigated in this study. Nano fibers show adsorption metal ions more than the usual fiber because of high ratio of surface to mass.     

High-efficiency mechanochemical synthesis of Strontium carbonate nanopowder from Celestite

In this study, the conversion of Celestite to SrCO₃ was studied by wet mechanochemical synthesis in a high-energy ball mill and treatment with Na₂CO₃. For this purpose, solid strontium carbonate and soluble Na₂SO₄ were obtained after wet milling of Celestite powder and sodium carbonate. The solid phase was washed with water at room temperature by filter pressing. X-Ray diffraction patterns showed that the SrCO₃ nanopowder was synthesized and conversion boosted with increasing the milling time up to 8 hours Also, Rietveld refinement analysis was used to calculate the fraction of SrCO₃ as well as structural properties of synthesized samples. It was found that initial Celestite could be converted to strontium carbonate with a purity more than 98% using high-energy milling without simultaneous heating. The optimum milling time was determined as 4 hours resulting in formation of nanopowders with an average particle size around 90 nm. Field Emission Scanning Electron Microscopy (FE-SEM), clearly showed the nanoscale structure of the synthesized powders.     

Octafilar Helical Antenna for Circular Polarization Wireless Capsule Endoscopy Applications

Wireless Personal Communications - This paper introduces a proposed design of a circularly polarized quadfilar or octafilar helical antenna (QFHA or OFHA) dedicated for wireless...     

A CSO-based approach for secure data replication in cloud computing environment

The Journal of Supercomputing - Cloud computing has a significant impact on information technology solutions for both organizations and researchers. Different users share critical data over the...     

The baric coefficient of resistance of Mn1.9Cr0.1Sb as measured by the double AC method

The baric coefficient of resistance of the magnetocaloric cycle working medium Mn_1.9C_r0.1Sb, aside from the peak which is expected and related to the pressure shift of the AF–Fr transition temperature T_S(p), shows two sidebands which are probably related to the percolation of phase domains.