Applied Mechanics and Materials Vol. 848

Abstract: This research work offers the new organic compound which has potential to replace the use of tributylin (TBT) in antifouling application. All modified chitosan powders were synthesized using in-house powder processing techniques. Pure and modified chitosan were evaluated for fouling properties via antimicrobial activity test against Cobetia Marina (C. Marina). The results indicated that copper substituted chitosan (CS-Cu) showed the highest inhibition zone and lowest number of C. Marina survival. It can be implied that CS-Cu showed the best antimicrobial ability against C. Marina.

Abstract: Sulfur cycling based on biological oxidation of sulfide to sulfate involves sulfur-oxidizing reducing microbial communities associated with sulfide which normally oxidize sulfide in acidic environment to sulfate. The chemolithotrophic sulfur oxidizing bacteria (SOB) usually use organic and/ or inorganic sulfide initially oxidizing and subsequently released sulfate under aerobic or subaerobic condition. This study was to understand SOB community isolated from coal mine treating plant at Mae Moh, Lampang and their potentials in hydrogen sulfide (H₂S) removal. In this result, with common heterotrophic medium supplemented with glucose 10 mg/ L and sulfur 0.001%, the cultured SOB were successfully cultivated based on most probable number method. Their activity showed an increase in sulfate concentration over time correspondent to an increase in culturable SOB communities. The SOB community could also develop their own microbial niches in the present of continuously aerated H₂S in the medium at 30-40°C during 7 day incubation. They could remove H₂S between 200-500 ppm from wastewater. These sulfur oxidized H₂S contaminated in wastewater treatment facilities or drainage. Their species will be further isolated and characterized by molecular analysis.

Abstract: Varieties of long known traditional fermented beverages are developed since their unique delicious and aroma. Additional nutrition value added in fermented drinks revealing their health benefits are especially interesting for the consumers nowadays. In the fermentation process isolated indigenous microbes habituated on the fruit surface as well as inoculated commercial species or niches have been shown for their success in Saccharification process. In this study, the researchers have applied our identified microbial mixtures isolated to be anticipating community starter in sugar production process. In addition, they were aimed to do enhancing nutritional value to the fermented juice. The selective cultures were obtained from fermented banana juice including yeasts Saccharomyces spp. and bacteria Lactobacillus sp., and Bacillus sp., yielding high protein contents, sweet aroma, and organic acids. Moreover, it was observed that weak acidity with pH 3-4 together with high reducing sugar and nutritious protein contents could be detected if particularly prior activated microbes were incubated for at least 10-15 days in fragrant bananas juice and two banana varieties; Naamwa banana (Musa sapientum L.) and lady finger banana. The modified wine fermentation approach of microbe mixtures can considerably use to improve the unique characteristics of wine that are nutritive protein supplementation as well as juice fermentation savour.

Abstract: It has been known for the diversified microbes living in the soil are basic indicators of changes in the ecosystem especially in paddy soil. The effects of continuous application of pesticides in rice field are widely discussed but still disregarded due to unclear and underestimated by the users and the chemicals also need time to accumulate and slowly affect the environment and health. The objective of this research was to understand the effects of pesticides on microorganism community in rice field. Both the numbers and the types of useful soil microorganisms including nitrogen fixing and common habituated microorganisms were compared in between using and not using chemical pesticides samples. The results showed that productivity of cultured microorganisms in the paddy applied with pesticides has dropped only slightly (approximately 9% reduction), however, more spore-forming Gram positive bacteria were detected. Additionally, increases in common microorganisms in the soil at a depth below than 20-50 cm were observed that could possibly be because of less pesticide availability there comparing to the surface of paddy soil. Although the changes in numbers and types of culturable microbes in the paddy soil contaminated with chemical pesticides were less than the actual diversity of species and cultivars, this study could help primarily indicate the adverse effects of the use of chemical pesticides. They thus interfered the ecological balance of the number and type of microorganisms especially at the site doing pesticide application.

Abstract: In this research, the dyeing behavior of silk fabrics with lac was studied. The effect of different mordants concentration (potassium aluminium sulfate or alum, stannous chloride, ferrous sulfate and sodium chloride) with simultaneous mordanting procedures using pad-dry and pad-batch techniques on colour characteristics of the dyed samples was investigated. The colour fastness tests were washing and light of the dyed samples, the test results were determined according to the present ISO standard.The results show that silk fabric dyed without and with stannous chloride and sodium chloride mordant gave a shade of light pink, while those mordanted with aluminum potassium sulfate, had noticeably pink shade. The colour shade was light grey shades was obtained by adding ferrous sulfate mordant. The washing fastness property showed very poor level, while light fastness was fair level.

Abstract: In this research work, effect of plasma on metal absorption of cotton fabric is investigated. For this purpose the Air and Nitrogen plasma were used. Cotton samples were treated with the optimum conditions of plasma. Then both treated and untreated samples were inoculated by Silver and Iron metallic salts. The amounts of metal particle on the surface of samples were analyzed using Inductively Coupled Plasma (ICP) and Scanning Electron Microscope (SEM). The results show that, air plasma is more effective as compared with Nitrogen plasma for improving the metal absorption of cotton fabric. It can be concluded that, plasma can be a useful method for improving the sorption active materials properties.

Abstract: This research was concerned with dye extraction from lac, purple corn cob, golden shower tree seed pods, garcinia dulcis bark and dried mangosteen leaves and application on cotton towel product dyeing by the use of exhaustion process. Cotton towel was pretreated using cationizing agent (Sarcat PD) before dyeing. Cotton towel dyed in the solution extracting from lac showed pink shade. The sample dyed with purple corn cob and golden shower tree seed pods resulted in violetish-brown and dark brown shades, respectively. With garcinia dulcis bark and dried mangosteen leaves the colour was yellow and brownish orange. The results showed that the dyes K/S values of the treated cotton towel were improved compared with those of the un-treated one.

Abstract: The purpose of this research was undertaken to use flour of wild taro corm (Colocasia Esculenta (L.) Schott) as a resist paste for batik on cotton fabric and using dye solution from pigment dyestuffs. Colour value, K/S values, sharpness of cotton batik fabric were evaluated. The washing and rubbing fastness of the batik fabric was also evaluated. From the result of experiment it can be concluded that the pattern at resist area of cotton batik fabrics show sharpness. Colour fastness to washing and rubbing were ranging between good to very good level. Pigment dye solution can be painted on cotton fabric by using batik technique.

Abstract: Warp yarn of cotton samples were printed with pigment dyes has been investigated. The printed warp yarn was weaved by using white cotton yarn as a weft yarn. The physical properties were evaluated to testing in tensile strength and tearing strength of weaved samples, the test were determined according to ISO standard. The results showed that the tensile strength of three samples are shown to be in the range between 210 and 342 Newtons whereas tearing strength was in the range between 30 and 110 Newtons. The results indicated that the properties of printed samples (handling) were good to very good level.

Abstract: In this study, 12 commercially available paper towels were collected from the local market. Their tensile properties were investigated by Kawabata Evaluation System for Fabric (KES-F). Four tensile properties namely: (i) extensibility (EMT), (ii) tensile energy (WT), (iii) tensile resilience (RT) and (iv) linearity of WT (LT) were evaluated. Experimental results revealed that the tensile properties varied within the products. EMT was used as the key property for discussing the tensile properties of paper towels. However, when the different tensile properties were correlated, it was found that WT/RT, WT/EMT and RT/EMT had strong Pearson correlation. In addition, there was no significant statistically relationship between weight and thickness to EMT. Based on this study, it can provide some information about the tensile properties of paper towels in local market which may help the industry for further improving the product quality.