• Ocean and Polar Research
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• v.45 no.1
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• pp.1-9
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• 2023

Marine microalgae have different collection methods depending on their habitat. In the case of adhesive microalgae, it is difficult to separate organisms from the substrate surface, and contamination is likely to occur during the sampling process. In this study, we analyzed the collection efficiency of adhesive microalgae using three artificial fiber materials (nylon, blend fabric, and viscose rayon). Each fiber showed different fiber diameter and pore characteristics (nylon 26.09 ㎛, blend fabric 56.6 ㎛, viscose rayon 101.3 ㎛). In addition, attached organisms were collected on the surface of artificial substrates at Bukseong Port in Incheon using each tested fiber material. After that, we investigated the population and species composition. The highest number of cells was found in nylon, which was 8 times higher than in the least collected viscose rayon material. In addition, we identified 24 microalgal species from the substrate, demonstrating that the species composition differed from that of surface water. The number of collected microalgae species varied depending on the fiber materials, with nylon containing all the adhesive microalgae. In contrast, only a few microalgae were observed in other fibers. These results suggest that, of the tested fibers, nylon material may be suitable for collecting adhesive microalgae. As a result, this study may be useful for future research on adhesive microalgae.

• Fibers and Polymers
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• v.5 no.1
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• pp.1-5
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• 2004

The ability of inherently conducting polymer (ICP) coated textiles to recover gold metal from aqueous solutions containing $[AuCl_4]^-$ was investigated. Nylon-lycra, nylon, acrylic, polyester and cotton were coated with a layer of polypyrrole (PPy) doped with 1,5-naphthalenedisulfonic acid (NDSA), 2-anthraquinonesulfonic acid (AQSA) or p-toluenesulfonic acid (pTS). Textiles coated with polyaniline (PAn) doped with chloride were also used. The highest gold capacity was displayed by PPy/NDSA/nylon-lycra, which exhibited a capacity of 115 mgAu/g coated textile, or 9700 mgAu/g polymer. Varying the underlying textile substrate or the ICP coating had a major effect on the gold capacity of the composites. Several ICP coated textiles recovered more than 90 % of the gold initially present in solutions containing 10 ppm $[AuCl_4]^-$ and 0.1 M HCl in less than 1 min. Both PPy/NDSA/nylon-lycra and PAn/Cl/nylon-lycra recovered approximately 60 % of the gold and none of the iron present in a solution containing 1 ppm $[AuCl_4]^-$, 1000 ppm $Fe^{3+}$ and 0.1 M HCl. The spontaneous and sustained recovery of gold metal from aqueous solutions containing $[AuCl_4]^-$ using ICP coated textiles has good prospects as a potential future technology.

• Textile Coloration and Finishing
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• v.19 no.2
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• pp.14-23
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• 2007

This research article explores the use of phthalocyanine reactive dye on nylon substrate. The effect of factors such as pH, temperature, liquor ratio and alkali addition on level of dye exhaustion, fixation and total fixation efficiency. Low pH, high temperature and low liquor ratio were found to be suitable conditions for maximum % exhaustion values. The effect of sulphatoethylsulphone(SES) and vinylsulphone(VS) form of the dyes on level of dye fixation was also discussed. The optimized exhaustion (%E), fixation(%F) and total fixation efficiency were determined. Modification of the dyeing process with alkali addition displayed that dye fixation(%) increased by alkali addition. Vinylsulphone(VS) moiety of the dye was found to be superior to. maximum fixation (%F). Appropriate predictable empirical models, relatively a new approach in dyeing processes, were developed incorporating interactions effects of temperature, pH and liquor ratio for predicting % exhaustion, fixation and total fixation efficiency. The significance of the mathematical model developed was ascertained using microsoft excel regression(solver) analysis module. High correlation coefficient was obtained (R2=0.9895 for % exhaustion, R2=0.9932 for fixation, R2=0.9965 for total fixation efficiency) for the model which shows prominent prediction capacity of the model for my conditions. The predictable polynomial equations developed from tile experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• Journal of Sensor Science and Technology
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• v.26 no.6
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• pp.420-426
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• 2017

A colorimetric sensor was investigated to achieve a low-cost warning device for harmful gaseous formaldehyde (HCHO). The sensor is based on selective reactions between hydroxylamine sulfate and HCHO, leading to the production of sulfuric acid. The produced acid results in color-changing response through the acid-base reaction with dye molecules impregnated on a solid membrane substrate. For attaining this purpose, sensors were fabricated by drop-casting a dye solution prepared using different pH indicators on various commercially available polymer sheets, and their colorimetric responses were evaluated in terms of sensitivity and reliability. The colorimetric sensor using bromophenol blue (BPB) and nylon sheet was found to exhibit the best performance in HCHO detection. An initial bluish green of a sensor was changed to yellow when exposed to gaseous formaldehyde. The color change was recorded using an office scanner and further analyzed in term of RGB distance for quantifying sensor's response at different HCHO(g) concentrations. It exhibited a recognizable colorimetric response even at 50 ppb, being lower than WHO's standard of 80 ppb. In addition, the sensor was found to have quite good selectivity in HCHO detection under the presence of common volatile organic compounds such as ethanol, toluene, and hexane.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1273-1279
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• 2016

The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle ($410{\pm}10kg$) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

• Membrane Journal
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• v.25 no.1
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• pp.75-83
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• 2015

In this study, chlorophylls were been extracted from common local plants, deposited on polypropylene (PP) substrate using various approaches, and the oxygen generation effect of the chlorophylls were investigated. The loading of chlorophylls on the substrates was achieved by dipping and spraying methods, where the spraying coating showed overall better results regarding oxygen generation from the combustion experiments in the closed vessel or in the isolated vacuum oven cell than those of dip coating. In addition, a composite substrate was prepared by nylon6/6 nanofiber on the PP substrate, and it exhibited an increase in the activation of chlorophylls. In the case of samples containing titanium dioxide ($TiO_2$), the reaching time of oxygen concentration from 16% to 21% and the combustion test using a candle for a sample with 50% chlorophylls showed similar results to those of a sample without $TiO_2$. As such, combining a spray coating and $TiO_2$ incorporation into gas separation membrane systems are expected to be useful to understand the fundamentals of material properties for their applications as oxygen generation membranes and air filtration systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.363.2-363.2
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• 2016

Stretchable strain sensors are becoming essential in diverse future applications, such as human motion detection, soft robotics, and various biomedical devices. One of the well-known approaches for fabricating stretchable strain sensors is to embed conductive nanomaterials such as metal nanowires/nanoparticles, graphene, conducting polymer and carbon nanotubes (CNTs) within an elastomeric substrate. Among various conducting nanomaterials, CNTs have been considered as important and promising candidate materials for stretchable strain sensors owing to their high electrical conductivity and excellent mechanical properties. In the past decades, CNT-based strain sensors with high stretchability or sensitivity have been developed. However, CNT-based strain sensors which show both high stretchability and sensitivity have not been reported. Herein, highly stretchable and sensitive strain sensors were fabricated by integrating single-walled carbon nanotubes (SWNTs) and nylon textiles via vacuum-assisted spray-layer-by-layer process. Our strain sensors had high sensitivity with 100 % tensile strain (gauge factor ~ 100). Cyclic tests confirmed that our strain sensors showed very robust and reliable characteristic. Moreover, our SWNTs-based strain sensors were easily and successfully integrated on human finger and knee to detect bending and walking motion. Our approach presented here might be route to preparing highly stretchable and sensitive strain sensors with providing new opportunity to realize practical wearable devices.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.636-641
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• 1998

Digoxigenin (DIG) was used to prepare nucleic acid probe for the detection of RNA of potato leafroll virus (PLRV) in the potato leaf extracts. The 0.6 kb coat protein (CP) gene cDNA of PLRV in plasmid pSPT 18 vector was labeled with digoxigenin by in vitro run-off transcription and then used for cRNA probe. In the several buffers tested for increase the total RNA extraction efficiency AMES buffer was the most suitable for this detection method. The RNA extracts from potato leaves shown symptoms of PLRV were dot blotted onto nylon membrane and hybridized with labeled RNA probes. After hybridization, labeled RNA bound to PLRV RNA on membrane was detected with anti-digoxigenin alkaline phosphatase. 5-bromo-4-chloro-3-indolyl-phosphate/nitroblue tetrazolium (NBT) salt and CSPD were used as substrate for colorimetric and film exposure detection, respectively. These detection methods were very sensitive allowing for detection of 1/32 diluted total RNA extract from 100 mg leaf tissue.

• Textile Coloration and Finishing
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• v.18 no.4
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• pp.43-48
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• 2006

A phthalocyanine reactive dye was applied to nylon fibers to study the effects of the temperature and pH on % exhaustion and fixation. In addition, appropriate predictable empirical models, relatively new approaches in dyeing process, were developed incorporating interactions effects of temperature and pH for predicting the both % exhaustion and fixation. The significance of the mathematical model developed was ascertained using Excel regression (solver) analysis module. A very high correlation coefficient was obtained ($R^2=0.9895$ for % exhaustion, $R^2=0.9932$ for fixation) for the model which shows prominent prediction capacity of the model for the unknown conditions. The predictable polynomial equations developed from the Experimental results were thoroughly analyzed by ANOVA (Analysis of Variance) statistical concepts.

• ANNALS OF ANIMAL RESOURCE SCIENCES
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• v.30 no.3
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• pp.111-120
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• 2019

The objective of this study was to investigate the effect of different feed inoculation method on rumen fermentation in an in vitro. Three experimental treatments were used: control (CON, direct dispersion of feed (2 g) in rumen fluid), combinations of direct dispersion (1 g) and nylon bag (DNB, pore size: 50 ㎛, 1 g), and nylon bag (NB, 2 g). An in vitro fermentation experiment was carried out using strained rumen fluid for 48 h incubation time and timothy was used as a substrate. At the end of the incubation, in vitro dry matter digestibility (IVDMD), in vitro neutral detergent fiber digestibility (IVNDFD), pH, volatile fatty acids (VFA), ammonia nitrogen (NH₃-N), and microbial community were evaluated and gas production was estimated at 3, 6, 12, 24, 48 h incubation periods. Gas production was higher in CON than DNB and NB at 6 and 12 h incubation time (p<0.01). There were no differences in final gas production, pH, NH₃-N concentration, total VFA production, and VFA profiles among treatments. The IVDMD was lowest in CON (p<0.01) but the IVNDFD was not differed by feed distribution methods. There were no significant differences in general bacteria and fungi. Protozoa count was highest in NB treatment among treatments (p<0.01). The abundance of cellulolytic bacteria, Ruminococcus flavefaciens and Fibrobacter succinogenes, was highest in the CON among treatments (p<0.01).