• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.5
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• pp.23-29
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• 2013

Various properties of cotton handsheet were measured to solve the problem of deformation while storing guar gum(natural polymer) and to improve strength and retention by synthetic polymers(A-PAM, C-PAM, CMC). The results of this study were summarized as follow. The cotton handsheet with 0.2% of A-PAM showed the best tensile index and folding endurance. Retention of fines and fillers in pulp slurry with 0.2% and 0.3% of A-PAM were more excellent than that with guar gum.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.308-311
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• 2004

Many researchers have reported that adding steel fiber to concrete improved its tensile and flexural strength significantly, but relatively few studies have been made on the compressive behavior of SFRC(steel fiber reinforced concrete). It is still less in case of high strength SFRC. The main objective of this research is to examine the effect of adding steel fiber on the compressive strength of high strength SFRC using fiber reinforcing index$(RI,\;V_f(l/d))$. It was found from the study that compressive strength was noticeably increased in proportion to RI.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.68-74
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• 2016

Nanofibrillated cellulose (NFC) was prepared from cotton linter after electron beam irradiation to investigate its effects on the manufacturing efficiency of the NFC preparation and the property changes by the treatment. Mechanical device (Super Masscolloider) was used to prepare the NFC and its passing frequency for each NFC preparation was recorded. More electron beam irradiation resulted in less passing frequency. Alpha cellulose content, molecular weight, crystallinity index, and thermal decomposition behavior of each treatment were lowered by electron beam treatment (10 and 100 kGy) and grinding process. NFC films were prepared to investigate their mechanical properties. There were little changes in tensile properties of the NFC films.

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.91-98
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• 1993

The silk fabrics were treated with color solution extracted from leaf of Camellia. The depression effect of destruction and yellowing of silk treated with color solution, shift of UV-VIS spectra of color solution, color difference of silk fabrics by dyeing with acid dyes and drycleaning fastness of silk treated with color solution were studied. UV-VIS spectra appeared to hypsochromic shift by irradiation. The decrease of tensile strength and the elongation of the silk treated with color solution showed depressed but those of untreated silk increased by irradiation. The yellowness index of silk treated with color solution showed a little change by irradiation. The color difference after dyeing with several acid dyes on treated and untreated silk showed not remarkable changes. Dsrycleaning fastness of silk treated by color solution was excellent.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.342-347
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• 2005

Photocurable hyperbranched acrylates were prepared from acrylic acid and hyperbranched polyol (HBP-16, 32, 64). Physical properties of three kinds of photocurable hyperbranched acrylated were investigated. Thermal stability of UV cured film measured by TGA shifted to higher temperature with increasing of functionality. Hardness, abrasion resistance, and tensile strength of UV cured film also increased with increasing functionality of acrylate. Weathering test for UV cured film showed the value of yellow index increased with increasing functionality of acrylate.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.16-23
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• 2004

Recently the increased concerns about the cost reduction and environmental protection make the paper industry increase the closure level of papermaking system, which results in the buildup of organic and inorganic materials in the papermaking process water. Increase of the system closure causes deterioration of additive performance and provokes diverse problems in papermaking process and product quality. To investigate the effects of process water quality on the physical properties of fine papers handsheets were prepared with process water containing various amounts of inorganic and organic contaminants including calcium or sodium ions and oxidized or cationic starches. Inorgainc and organic materials did not show any significant effect on the physical properties of handsheets. Recycled GCC showed the same trends as inorganic and organic materials. The performance of cationic starch was deteriorated, however, in the recycled white water, which resulted in the reduction of tensile index of handsheets.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.4
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• pp.33-38
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• 2010

The effects of fillers on the wet end dewatering and paper properties were investigated in order to confirm the possibility that the fillers can be used as a means for saving energy in papermaking process. The performance of GCC, PCC and talcs were evaluated. The dewatering in wire and wet press was improved by the increase of filler addition, but it was observed that the dewatering behavior was depended by the filler characteristics. PCC was superior to other fillers in the bulk, opacity, air permeability and stiffness while the lowest tensile and burst index were obtained. We found that the response on the wet end dewatering and paper properties were affected greatly by the filler characteristics including particle shape and size.

• Textile Coloration and Finishing
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• v.7 no.3
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• pp.1-10
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• 1995

The optical behavior of coloring matter extracted from onion's coats, the depression effects of destruction, yellowing and W transmittance of silk treated with color solution of onion's coats color difference of silk fabrics dyed with acid dyes and drycleaning fastness of silk treated with color solution has been investigated. The results are as follows : 1) The coloring matter extracted from onion's coats by alkali-acid method appeared properties of aglycon type. 2) &{\lambda}_{max}&of color solution extracted by distilled water was found at 280 and 327nm. 3) The decrease of tensile strength and the elongation of the silk treated with color solution were depressed but those of untreated silk were increased by irradiation of UV light. 4) The yellowness index of silk treated with color solution showed a little change by irradiation. 5) The UV transmittance of silk treated with color solution was decreased as increasing concentration of color solution. 6) The color difference after dyeing with several acid dyes on treated and untreated silk fabrics showed remarkable changes. 7) Drycleaning fastness of silk treated by color solution was excellent.

• Journal of the Korean Home Economics Association
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• v.42 no.8
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• pp.113-121
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• 2004

This study used cupric sulfate as a bum-out agent. The concentration of cupric sulfate, temperature and time were varied with glycerin included or excluded on the properties of polyester ground fabrics. The results are as follows. The effect of carbonization with glycerin included was decreased, but removal of carbide with glycerin included was easier than that with glycerin excluded. The white index and tensile strength of polyester ground fabrics were decreased as the processing concentration, temperature and time increased. The shrinkage was increased as the processing concentration, temperature and time increased. The optimum conditions with cupric sulfate as the bum-out agent was 5％ concentration, 140$^{\circ}C$, 3min., and 3kgf/cm$^2$ and with cupric sulfate added to glycerin was 5％ concentration, 150$^{\circ}C$, 5min., and 3kgf/cm$^2$.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.1
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• pp.31-37
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• 2015

A laser line welder using a solid-state laser (Yb:YAG) has been manufactured for joining ultra-thin cold-rolled steel coils in steelworks. The coils to be welded primarily range from 0.15 to 0.3 mm in thickness and 800 to 1,100 mm in width. Because the steel plate is extremely thin, it is very important to control the stop positions of the clamp at cutting and welding points. In this study, both hydraulic proportional control valves and LVDT sensor embedded cylinders were used to precisely control and monitor the positions of clamps with complementary stoppers. As a result, the positions could be controlled within an error of ${\pm}30{\mu}m$. Erichsen cupping tests on the welded joints show that the Erichsen index ranges from 4.4 to 4.6 mm. Furthermore, the tensile strength of welding points is comparable to that of the base metal.