Fast Stiffness Matrix Calculation for Nonlinear Finite Element Method

We propose a fast stiffness matrix calculation technique for nonlinear finite element method (FEM). Nonlinear stiffness matrices are constructed using Green-Lagrange strains, which are derived from infinitesimal strains by adding the nonlinear terms discarded from small deformations. We implemented a linear and a nonlinear finite element method with the same material properties to examine the differences between them. We verified our nonlinear formulation with different applications and achieved considerable speedups in solving the system of equations using our nonlinear FEM compared to a state-of-the-art nonlinear FEM. © 2014 Emir Gülümser et al

The combination of atmospheric plasma and chemical treatments for antibacterial finish on cotton

The aim of this study was to investigate the incorporation of triclosan based chemical into cyclodextrin based commercial product, bonded onto cotton fabric with and without plasma modification. The treated samples were characterized by SEM analysis. The antibacterial activities of the washed and unwashed samples were evaluated according to the AATCC Test Method 147-1998 and some physical properties were also investigated. It was observed that after the combination process of triclosan, cyclodextrin and atmospheric plasma modification, cotton fabric was able to retain its antibacterial activity up to the 5 washing cycles at 60°C

Microencapsulation of melaleuca alternifolia (tea tree) oil by using simple coacervation Method)

Glutaraldehyde (GA) crosslinked gelatin (G) microcapsules containing tea tree oil (TTO) were prepared by the simple coacervation technique. The effects of variations in concentrations of the G, TTO and GA used during the microencapsulation process, on the oil load of the microcapsules, the oil content, the encapsulation efficiency and the release rate of oil were determined. The size distribution and the morphology of the microcapsules were characterized by optical and scanning electron microscopy. It was determined by FTIR studies that there was no evidence for any significant interaction between G and TTO. © 2011 Allured Business Media

An ecological approach for the surface modification of aramid fibers

Since aramid fibers have very high crystallization degree and high chemical inertness, the surface modification is needed to enhance the adhesion between fibers and matrix for the usage of composite applications. In the present study, para-aramid fibers were treated by atmospheric pressure plasma under various plasma powers to improve interfacial adhesion between aramid fiber and epoxy resin. The surface morphologies of untreated and treated fibers were investigated by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Composite interfacial adhesion properties were determined by interlaminar shear strength (ILSS) using a short-beam bending test. Results indicated that argon plasma treatment was an effective method for improving interfacial adhesion between fiber and matrix with ecological treatment

Effects of novel antibacterial chemicals on low temperature plasma functionalized cotton surface

Since natural fibers are very susceptible to bacterial attacks, various antibacterial finishes have been developed to control the bacterial growth. Metal and metal salts, quaternary ammonium compounds, N-halamines, chitosan, polybiguanids and halogenated phenols can be used for antibacterial finishes. On the other hand, plasma treatment has become very popular for improved antibacterial activity in recent times. In this study, the effect of argon plasma treatment on cotton fabrics before antibacterial finishing process was investigated. After antibacterial finish process, they were washed up to ten cycles. The antibacterial activities of the washed and unwashed samples were evaluated according to the AATCC Test Method 147-1998. The surface morphology was characterized by SEM and FTIR analysis. From the results, it's observed that plasma application clearly increased the antibacterial activity of the samples and the most efficient and washing durable antibacterial agent was non-ionic diphenylalkane based chemical agent. From the SEM images, it's seen that after argon plasma treatment, the cotton surface has become rougher and more silver particles have been attached to the surface. This fact was also confirmed by EDX analysis

The new routes of textile production from ecotextiles to organic textiles

S.C. Pielorex S.A.;S.C. Prodstefano S.R.L.;S.C. Taro Industry S.A.;S.C. Hofigal Export-Import S.A.;S.C. Class Shoe S.R.L.3rd International Conference on Advanced Materials and Systems, ICAMS 2010 -- 16 September 2010 through 18 September 2010 -- Bucharest -- 85353Environmental issues have been gaining importance with regard to all aspects of industrial production. There is also a growing trend for the general public to recognize the need for environmental protection. Ecology can be described as an environmental science that deals with the relationships between living organisms and their interactions with environment. The content of ecology has been enlarged due to its increasing importance and. this environmental action also affects the textile industry. Therefore, the "textile ecology" becomes pronounced. As an ecofriendly production method, "organic textile" concept has emerged in recent years. In organic textile production, all steps from fiber to the end product, there is no harmful effect on users and all products can be recycled without any harm to the environment. Organic textile is currently a niche market as compared to traditional textile and usually in a niche market; the profits are high due to less competition. As a niche marketing strategy, all the organizational efforts are used to satisfy the targeted customers, at substantial profits. In this study, an overview about textile ecology and organic textiles is given

Ecological printing of madder over various natural fibres

The applicability of madder by using printing technique over various natural fibers was investigated in the study. The effect of different factors, i.e. dye and urea concentration, type of fixation, fixation temperature and time, effect of mordant type and mordanting methods were studied. Printed fabrics were evaluated by means of color values and fastness properties. The K/S increases rapidly as the concentration of the natural dye powder in the printing paste increases from 15 to 45 g/kg printing paste. The effect of mordant on color was also studied. The results show that the highest K/S value was obtained by using mordant. Application of madder with the printing technique is expected to bring a different and an ecological alternative to new designs