Hooman Amid | North Carolina State University (original) (raw)
Papers by Hooman Amid
Adsorptive nonwoven substrates are composite media that contain adsorbent materials within their ... more Adsorptive nonwoven substrates are composite media that contain adsorbent materials within their fibrous structure; the methods to incorporate adsorbents in nonwoven webs determine their adsorption capacity. The key objective for hybridization is to immobilize the adsorbent while controlling the packing density and pressure drop of the composite media. Loading percentage of adsorbents, the accessible portion of their surface area, their attachment and stability within the structure, and time/cost/process to incorporate them is different for each hybridization technique. The general limitations associated with hybrid adsorptive nonwovens are summarized as surface area loss, process control, and production time/cost. The primary focus of this review is on hybridization techniques that incorporate activated carbons and/or metal-organic frameworks (MOFs) in nonwoven structures, used in gas filtration. It was concluded that coating, thermal bonding, lamination, and coform methods have higher throughputs compared to electrospinning. In addition, coform method provides better control over accessible surface area of adsorbents.
Many studies have investigated the anti-bacterial properties of nanosilver-finished textiles; how... more Many studies have investigated the anti-bacterial properties of nanosilver-finished textiles; however, physical and mechanical properties of such fabrics have not been studied as much. In the present study, we have examined some physical and mechanical properties of plain weave cotton fabrics before and after nanosilver finishing. Four nanosilver concentrations (100, 300, 500 and 700 parts per million (ppm)) were applied and the results were analyzed by ANOVA statistical tests. It was found that at high Ag concentrations (500 and 700 ppm) air permeability, tensile strength, failure elongation, and tear strength of the fabric reduced. Higher nanosilver concentrations (500 and 700 ppm) resulted in lower crease recovery and higher bending rigidity, and reduced the fabric comfort adversely. Based on the results, Ag concentration that would not reduce the fabric comfort is proposed.
AUTEX Research Journal, 2015
The main traditional technique for commercial manufacturing of composite pipes is filament windin... more The main traditional technique for commercial manufacturing of composite pipes is filament winding in which the winding angle and the discontinuity of the structure (caused by starting and ending points of the winding process) are two important matters of concern. In the present study, circular woven fabric with its orthogonal net-shaped continuous structure was produced from polyester yarns. The fabric was wet with epoxy and hand layup was used to manufacture the composite pipes. The composite pipes were subjected to internal hydrostatic pressure and their burst strength was recorded. In addition, the tensile strength of flat laminas was assessed in the warp and weft directions. We estimated and analyzed the failure strength of composite pipes using Tresca’s failure criterion and Finite Element (FE) modeling. The experimental burst strength was almost 23% more than the FE model and 77% more than the theoretical estimate.
Proceedings of The 11th Asian Textile Conference 2011, Daegu, Korea, Nov 1, 2011
In the present study the possibility of manufacturing tubular woven fabric as the reinforcement p... more In the present study the possibility of manufacturing tubular woven fabric as the reinforcement part of composite pipes has been investigated. For this purpose some special settings have been applied to a shuttle loom. On the other hand, four different types of yarns have been examined to suit the loom setting and final application as the reinforcement. Eventually high tenacity polyester has been found to fit the conditions. In conclusion tubular fabrics have been used as the reinforcement of single-layer flat composite and their tensile strength in weft and warp directions have been measured and compared to the tensile strength of standard cast iron, which is normally used in piping industry. Finally the internal hydrostatic pressure strength of tubular composite can be determined theoretically (which is the aim of next study). Results showed that cast iron can be replaced with this fabric-reinforced composite in pipes.
1st SMARTEX-Egypt 2011 (World Textiles Conference), Kafrelsheikh University, Egypt, May 23, 2011
In the present study the effects of nano-silver finishing on some physical and mechanical propert... more In the present study the effects of nano-silver finishing on some physical and mechanical properties of plain weave cotton fabrics have been investigated. Specimens have been finished with four distinct solution concentrations (S.C.), 100,300,500 and 700 PPM. Results show that by increasing the S.C. of nano-silver in the finishing process, water vapor permeability has been increased gradually. Also there is a small increment in the bending length up to S.C. of 500 PPM and a sudden drop occurred for that of 700 PPM, in both warp and filling directions. By applying the finishing treatment at the first step (100 PPM), crease recovery soared. However, by increasing the S.C. it began to decrease in both directions. On the other hand, applying the finishing process does not affect the breaking strength and breaking elongation significantly at S.C. of 100 PPM and 300 PPM, but at S.C. of 500 PPM and 700 PPM a drastic fall has been observed.
Proceedings of The 11th Asian Textile Conference 2011, Daegu, Korea, Nov 1, 2011
Heat properties, considered as the fabric’s principal characteristics, are not only important ind... more Heat properties, considered as the fabric’s principal characteristics, are not only important indexes for determining the comfort of cloths but also features to evaluate the heat insulating quality in industry. In this study, an ISO based instrument has measured heat properties of knitted fabrics, so that effects of inserted weft yarn type, plying, and weft insertion arrangement on heat properties were investigated. Acrylic 1×1 Rib fabrics which were produced by a flat knitting machine were weft inserted with 6 types of weft yarns, in two arrangements: every single course and every six courses a weft. Results indicate better heat resistance and less stitch density of the every-course-weft-inserted samples, in comparison to those of every-six-courses-a-weft samples. Glass-fiber weft-inserted samples had the best heat resistance and least heat conduction. Plying the weft yarn results in decreasing the stitch density leading to an increase in heat conduction.
7th International Conference - TEXSCI 2010, Liberec, Czech Republic, Sep 6, 2010
Fabric comfort is determined by its physical and mechanical properties which are being influenced... more Fabric comfort is determined by its physical and mechanical properties which are being influenced by the finishing treatment such as finishing by nano materials. In this study the effects of nano-silver finishing on the physical and mechanical properties of plain weave cotton fabrics have been examined. Specimens have been finished with four distinct solution concentrations (100, 200, 300 and 400 PPM) and finally they have been compared to the raw fabric. The physical and mechanical properties including air permeability, wrinkle recovery, water vapor permeability, breaking strength, breaking elongation and bending length have been measured. The results show that by increasing the solution concentration of the nanosilver finish, air permeability has been dwindled and there is a great difference between nano-finished specimens and the unfinished one. Also by increasing the solution concentration, a slight decrease in wrinkle recovery and an
irregular decline in water vapor permeability have been observed. Also an irregular increase in breaking strength has been perceived and a considerable raise in the breaking elongation and bending length in both warp and filling directions was observed.
It is worthwhile to be mentioned that all these consequences have been confirmed by the mean of statistical analysis.
Adsorptive nonwoven substrates are composite media that contain adsorbent materials within their ... more Adsorptive nonwoven substrates are composite media that contain adsorbent materials within their fibrous structure; the methods to incorporate adsorbents in nonwoven webs determine their adsorption capacity. The key objective for hybridization is to immobilize the adsorbent while controlling the packing density and pressure drop of the composite media. Loading percentage of adsorbents, the accessible portion of their surface area, their attachment and stability within the structure, and time/cost/process to incorporate them is different for each hybridization technique. The general limitations associated with hybrid adsorptive nonwovens are summarized as surface area loss, process control, and production time/cost. The primary focus of this review is on hybridization techniques that incorporate activated carbons and/or metal-organic frameworks (MOFs) in nonwoven structures, used in gas filtration. It was concluded that coating, thermal bonding, lamination, and coform methods have higher throughputs compared to electrospinning. In addition, coform method provides better control over accessible surface area of adsorbents.
Many studies have investigated the anti-bacterial properties of nanosilver-finished textiles; how... more Many studies have investigated the anti-bacterial properties of nanosilver-finished textiles; however, physical and mechanical properties of such fabrics have not been studied as much. In the present study, we have examined some physical and mechanical properties of plain weave cotton fabrics before and after nanosilver finishing. Four nanosilver concentrations (100, 300, 500 and 700 parts per million (ppm)) were applied and the results were analyzed by ANOVA statistical tests. It was found that at high Ag concentrations (500 and 700 ppm) air permeability, tensile strength, failure elongation, and tear strength of the fabric reduced. Higher nanosilver concentrations (500 and 700 ppm) resulted in lower crease recovery and higher bending rigidity, and reduced the fabric comfort adversely. Based on the results, Ag concentration that would not reduce the fabric comfort is proposed.
AUTEX Research Journal, 2015
The main traditional technique for commercial manufacturing of composite pipes is filament windin... more The main traditional technique for commercial manufacturing of composite pipes is filament winding in which the winding angle and the discontinuity of the structure (caused by starting and ending points of the winding process) are two important matters of concern. In the present study, circular woven fabric with its orthogonal net-shaped continuous structure was produced from polyester yarns. The fabric was wet with epoxy and hand layup was used to manufacture the composite pipes. The composite pipes were subjected to internal hydrostatic pressure and their burst strength was recorded. In addition, the tensile strength of flat laminas was assessed in the warp and weft directions. We estimated and analyzed the failure strength of composite pipes using Tresca’s failure criterion and Finite Element (FE) modeling. The experimental burst strength was almost 23% more than the FE model and 77% more than the theoretical estimate.
Proceedings of The 11th Asian Textile Conference 2011, Daegu, Korea, Nov 1, 2011
In the present study the possibility of manufacturing tubular woven fabric as the reinforcement p... more In the present study the possibility of manufacturing tubular woven fabric as the reinforcement part of composite pipes has been investigated. For this purpose some special settings have been applied to a shuttle loom. On the other hand, four different types of yarns have been examined to suit the loom setting and final application as the reinforcement. Eventually high tenacity polyester has been found to fit the conditions. In conclusion tubular fabrics have been used as the reinforcement of single-layer flat composite and their tensile strength in weft and warp directions have been measured and compared to the tensile strength of standard cast iron, which is normally used in piping industry. Finally the internal hydrostatic pressure strength of tubular composite can be determined theoretically (which is the aim of next study). Results showed that cast iron can be replaced with this fabric-reinforced composite in pipes.
1st SMARTEX-Egypt 2011 (World Textiles Conference), Kafrelsheikh University, Egypt, May 23, 2011
In the present study the effects of nano-silver finishing on some physical and mechanical propert... more In the present study the effects of nano-silver finishing on some physical and mechanical properties of plain weave cotton fabrics have been investigated. Specimens have been finished with four distinct solution concentrations (S.C.), 100,300,500 and 700 PPM. Results show that by increasing the S.C. of nano-silver in the finishing process, water vapor permeability has been increased gradually. Also there is a small increment in the bending length up to S.C. of 500 PPM and a sudden drop occurred for that of 700 PPM, in both warp and filling directions. By applying the finishing treatment at the first step (100 PPM), crease recovery soared. However, by increasing the S.C. it began to decrease in both directions. On the other hand, applying the finishing process does not affect the breaking strength and breaking elongation significantly at S.C. of 100 PPM and 300 PPM, but at S.C. of 500 PPM and 700 PPM a drastic fall has been observed.
Proceedings of The 11th Asian Textile Conference 2011, Daegu, Korea, Nov 1, 2011
Heat properties, considered as the fabric’s principal characteristics, are not only important ind... more Heat properties, considered as the fabric’s principal characteristics, are not only important indexes for determining the comfort of cloths but also features to evaluate the heat insulating quality in industry. In this study, an ISO based instrument has measured heat properties of knitted fabrics, so that effects of inserted weft yarn type, plying, and weft insertion arrangement on heat properties were investigated. Acrylic 1×1 Rib fabrics which were produced by a flat knitting machine were weft inserted with 6 types of weft yarns, in two arrangements: every single course and every six courses a weft. Results indicate better heat resistance and less stitch density of the every-course-weft-inserted samples, in comparison to those of every-six-courses-a-weft samples. Glass-fiber weft-inserted samples had the best heat resistance and least heat conduction. Plying the weft yarn results in decreasing the stitch density leading to an increase in heat conduction.
7th International Conference - TEXSCI 2010, Liberec, Czech Republic, Sep 6, 2010
Fabric comfort is determined by its physical and mechanical properties which are being influenced... more Fabric comfort is determined by its physical and mechanical properties which are being influenced by the finishing treatment such as finishing by nano materials. In this study the effects of nano-silver finishing on the physical and mechanical properties of plain weave cotton fabrics have been examined. Specimens have been finished with four distinct solution concentrations (100, 200, 300 and 400 PPM) and finally they have been compared to the raw fabric. The physical and mechanical properties including air permeability, wrinkle recovery, water vapor permeability, breaking strength, breaking elongation and bending length have been measured. The results show that by increasing the solution concentration of the nanosilver finish, air permeability has been dwindled and there is a great difference between nano-finished specimens and the unfinished one. Also by increasing the solution concentration, a slight decrease in wrinkle recovery and an
irregular decline in water vapor permeability have been observed. Also an irregular increase in breaking strength has been perceived and a considerable raise in the breaking elongation and bending length in both warp and filling directions was observed.
It is worthwhile to be mentioned that all these consequences have been confirmed by the mean of statistical analysis.