• Title/Summary/Keyword: Alkali swelling

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X-Ray Diffraction Study on the Cellulose Structures in Wood Cell Wall (X선 회절법을 이용한 목재세포벽중의 셀룰로오스의 구조해석)

  • 김남훈;이선호
    • Journal of Korea Foresty Energy
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    • v.18 no.2
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    • pp.62-69
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    • 1999
  • Lignin in wood cell walls influeced the transformation of the cellulose crystal structure during mercerization. Samples of sound and decayed woods by white rot fungus of Quercus mongolica were treated with 20% aquous NaOH solution, followed by washing and drying, and delignified. The effect of delignification on cellulose structure was investigated by a series of an X-ray diffraction analysis and ultraviolet(UV) microscopy. Delignification of alkali-treated woods did not influence their cellulose crystal structures. It may be concluded that lignin prevents the swelling of wood cellulose during mercerization and restrain the intermingling of cellulose chains.

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Characteristics of Fancy Veneer Plywood Floor using Green Tea Leaves Powder (녹차잎분말을 사용한 마루판의 특성)

  • Kang, Seog-Goo;Lee, Hwa-Hyoung
    • Journal of the Korea Furniture Society
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    • v.21 no.4
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    • pp.284-292
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    • 2010
  • This research was carried out to examine the properties of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood floor, which 2.5% green tea leaf powder was applied in the UV varnishes and the adhesives for scavenging the volatile organic compounds. The results were as follows: 1. The various properties of the treated samples, such as density, moisture content, thickness swelling, bending strength(MOR), adhesion shear strength, surface abrasion, curling, cyclic delamination test with boiling water, boiling property, cold-resistance and heat resistance, acid resistance and alkali resistance, and anti-contamination property showed no significant difference between the properties of the control samples. 2.5% green tea leaf powder treated floor gave a little better results than the control for surface scratch test. 2. In case of QUV and weathering test, no difference between the treated sample and control was found. 3. The floor was discolored by adding 10% green tea leaf powder to UV coating, and the floor was also discolored to light green during by the soaking test. The color of floor was not changed up to 5% addition level.

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A Study on the Synthesis of Starch-Acrylic Polymer by Emulsion Polymerization (유화중합에 의한 전분-아크릴 고분자의 합성에 관한 연구)

  • Lee, Mi-Suk;Ryu, Hoon;Cho, Ur-Ryong
    • Polymer(Korea)
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    • v.34 no.1
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    • pp.58-62
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    • 2010
  • The acrylic monomers were graft-polymerized to starch as matrix polymer by emulsion polymerization. Viscosity and particle size of the emulsion were increased with starch contents due to interaction with water and particle swelling toward the water phase by hydroxy group of starch. Chemical stability of the emulsion was also increased with enhancement of starch, but water and alkali resistance were reduced with increasing starch contents because of the increasement of hyrophilicity. Opacity of the starch-acrylic emulsion compound containing calcium carbonate was decreased with contents of starch by its intrinsic color. The film of starch-acrylic polymer showed more clear appearance with increasing starch contents owing to enhancement of amorphous state.

A Study on Polyester Fabric treated with Quarternary Ammonium Salt and Alkali (사급암모늄염/수산화나트륨용액에서 폴리에스테르 직물의 알칼리처리에 관한 연구)

  • 류효선
    • Journal of the Korean Home Economics Association
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    • v.25 no.4
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    • pp.9-18
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    • 1987
  • This study is conducted to investigate the influence of addition of quarternary ammonium salt(cetyl trimethyl ammonium bromide: CTAB) when polyester(PET) fabric is treated with sodium hydroxide(NaOH), depending on experimental variables such as CTAB concentration, NaOH concentration, time & temperature, and the change in physical & chemical properties of alkaline-hydrolyzed PET fabrics depending on their weight loss. The results are as follows: 1. By adding CTAB in aqueous NaOH, the weight loss of PET fabric is increased remarkably and until the concentration of CTAB is reached at its cmc, and the higher the concentration of CTAB are, the more weight loss on PET fibrics are. 2. The addition of CTAB in aqueous NaOH is most effective at lower NaON concentration(2%) among various NaOH concentration, on increasing the amount of weight loss, while there are almost similar results through various treatment time and temperature. 3. As the amount of weight of weight loss on PET fabric is increased, the increase of void space in the PET yarn, of softness & dyeability of PET fabric and the decrease of tensile strength are found. On the other hand, the moisture regain shows a little increase by alkaline-hydrolysis on PET fabric while vertical absorption test & water retention value are not sufficiently sensitive to distinguish between the hydrophillicity of untreated and treated PET fabric. The shrinkage of PET fabric is induced by swelling in hot aqueous NaOH regardless of NaOH concentration & addition of CTAB.

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Effects on Mechanical Strength Improvement of Liner Paper using Recycled Fibres from Waste Cotton Clothes (폐 면직물 재활용 섬유를 이용한 라이너지의 강도개선 효과)

  • Hong, Seok-Jun;Park, Jung-Yoon;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.6
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    • pp.94-102
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    • 2014
  • The physical and chemical properties of recycled fibers from mixed waste paper are more and more deteriorated because of unknown history of recycling times. In order to improve the mechanical properties of liner paper, the recycled fibers from wasted cotton clothes were used in papermaking process, and their applicabilities were evaluated in several points of fiber modification. Thus, two kinds of fiberizing methods from waste cotton clothes were considered by using rotary sandpaper and grinder mill. Finally, the rotary sandpaper method was relatively desirable in preserving longer fiber length and fibrillated fiber surface. The recycled cotton fibers by swelling treatment with NaOH and bleaching with reductive chemicals were mixed with OCC fibers, and the handsheets were prepared to basis weight of $80g/m^2$ and evaluated the mechanical properties of paper. The fibrous properties showed outstanding results in freeness and WRV improvements by alkali treatment and high brightness by reductive bleaching treatment. The physical and mechanical properties of sheet by mixing OCC fibers and recycled cotton fibers were also highly improved in tensile, burst strength and specially folding resistance.

Physicochemical properties of large and small granules of naked barley starches (쌀보리 전분의 입자 크기별 이화학적 성질)

  • Oh, Keum-Soon;Kang, Kil-Jin;Kim, Kwan;Kim, Sung-Kon
    • Applied Biological Chemistry
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    • v.35 no.1
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    • pp.10-13
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    • 1992
  • Starches from three varieties of naked barley were fractionated into two populations according to the granule sizes and physicochemical properties were compared. Number of small granules was comprised in 62% of Saessalbori and 75% of Nulssalbori and Mudungssalbori. The proximate composition and water binding capacity were lower in large granules, the large granules showed higher values in blue value and intrinsic viscosity than those of small ones. There no differences in swelling power and X-ray diffraction pattern between small and large granules. The viscosities of alkali-gelatinized starch were higher on large granules, but the temperature of birefringennce loss was not different.

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Comparison of Physicochemical Propertres of Various Bean Starches -Cowpea, mung bean, kidney bear and red bean- (두류 전분의 이화학적 특성비교 -동부, 녹두, 강낭콩, 팥-)

  • Sohn, Kyung-Hee;Yoon, Gae-Soon;Chung, Hea-Jung;Chae, Sun-Hee
    • Korean journal of food and cookery science
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    • v.6 no.1
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    • pp.13-19
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    • 1990
  • Cowpea, mung bean, Kidney bean and red bean are simular properties. In order to elucidate the similarity among these four starches, some physicochemical properties of starches were compared. Water binding capacity of kidney bean and red bean (199%) starches are higher than mung bean and cowpea. The solubility, swlling power and optical transmittance of the four starches showed a similar pattern, but kidney bean and red bean starches had a lower swelling power than cowpea starches. Cowpea, mung bean, kidney bean and red bean starches had the blue value of 0.41, 0.47, 0.42 and 0.50, the alkali content of 8.4, 8.0, 4.13, 4.13, the amylose content of amylose of 30,000, 29,268, 52, 173 and 33, 611 and glucose unit per segment of amylopectin of 27.6, 26.8, 18.35 and 12.9 respectively. The results of X-ray diffraction studies showed A pattern for four starches.

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Physicochemical Properties of Korean Ginseng (Panax ginseng, C.A. Meyer) Root Polysaccharides. -Change of physicochemical properties of the starch during storage and heat treatment- (인삼다당류의 이화학적 특성에 관한 연구 -인삼저장가공중 전분의 이화학적 특성변화-)

  • 조재호;오성기
    • Journal of Ginseng Research
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    • v.9 no.2
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    • pp.270-284
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    • 1985
  • In order to investigate the change of physicochemical properties of ginseng root starch during storage and heat treatment, the roots were stored for 15 days at 5 $^{\circ}C$, 15 $^{\circ}C$, 3$0^{\circ}C$ and 45$^{\circ}C$, and heated for 15 hours at 6$0^{\circ}C$, 7$0^{\circ}C$, 8$0^{\circ}C$, 9$0^{\circ}C$, respectively. The starch content was decreased from about 40% to 23-26% and sucrose content was increased from 4% to 12-16% during storage for 15 days at 5-45$^{\circ}C$. Maltose, which was not detected in fresh samples, was increased up to 8.5% during storage or heat treatment. Granular size of the starch was decreased and some of the granules were broken during storage. Amylose content in the starch was decreased from 33% to 20%, and blue value and alkali number of the starch were increased slightly, and solubility and swelling power of the starch were decreased during storage. 3 The higher storage temperature and the longer storage time, the starch was more susceptible to gelatinize, and the viscosity of the starch was lowered with the susceptibility of gelatinization. The susceptibility of degradation of the starch by the amylase was increased and amylolytic activities in ginseng root were, also, increased during storage.

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Physicochemical Properties of Waxy Barley Starch (찰보리 전분(澱粉)의 이화학적(理化學的) 특성(特性))

  • Yoon, Gae-Soon;Kang, Ock-Joo;Kim, Hyong-Soo
    • Applied Biological Chemistry
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    • v.27 no.2
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    • pp.79-85
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    • 1984
  • The physicochemical properties of starch isolated from two kinds of waxy barley were investigated. The average diameters of starch granules of Changyoung and Smire were 13.6 and 16.6 microns, respectively, and most of starch granules were round shape. X-ray diffraction patterns of two samples were A-types and amylose contents of two waxy barley starches were 4%, blue values and alkali numbers of Changyoung and Smire were 0.22 and 0.18, 5.2 and 4.0, raising powers of them were 167 and 173, respectively. The optical transmitance of 0.1% suspension of waxy barley starches increased rapidly from $51^{\circ}C\;to\;75^{\circ}C$. Amylogram data on 5% of Changyoung and Smire starch solutions showed the gelatinization temperature of 63 and $62^{\circ}C$, maximum peak hight of 920 and 900 B.U., respectively. Waxy barley starches had higher swelling powers than non waxy barley starch. The starch pastes prepared from waxy barleys retrograded much slower than that of non waxy barley.

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Physico-chemical Properties of Acetylated Rice Starches (초산 쌀전분의 이화학적 특성)

  • Jeong, Jae-Hong;Bae, Jung-Surl;Oh, Man-Jin
    • Korean Journal of Food Science and Technology
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    • v.25 no.2
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    • pp.123-129
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    • 1993
  • Physico-chemical properties of the acetylated and raw starch were Investigated with the chucheongbyeo and samkangbyeo. The solubility and swelling power was increased by acylation reaction. The light transmittance was higher in the acetylated rice starch. The blue value of chucheongbyeo and samkangbyeo rice starches were lowered to 10.9% and 16.0%, respectively, by the acylation reaction. The alkali number was 7.6 in the chucheongbyeo rice starch and 7.2 in the samkangbyeo rice starch, whereas acylated starch in the same orders was 55 and 52, respectively. The hardness, adhesion, cohesion of starch gel was increased by the acylation reaction. The temperature of initial gelatinization of the acetylated chucheongbyeo and samkangbyeo rice starch was shown to $59^{\circ}C\;and\;62^{\circ}C$, respectively, lowering $5{\sim}6^{\circ}C$ in temperature by the acylation. The viscosity as well as by the acylation reaction was raised 38% and 14%, respectively. The rice starch particles were shown to plygonal structure. But it were deformed in the acylated starch, and was completely destroyed in the starch which is by gelatinized for 30 min. at $70^{\circ}C$.

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