• 제목/요약/키워드: Water retention value

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An Alternative Fiber Processing Method

  • Seo, Yung-Bum;Lee, Chun-Han
    • 펄프종이기술
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    • 제43권5호
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    • pp.34-42
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    • 2011
  • A fiber processing method, which might be an alternative for conventional refining process, was introduced. The method consists of repetitive, gentle, mechanical impacts on fibers, followed by fiber uncurling process. This method was very effective for OCC and BCTMP for increasing WRVs (water retention value) while keeping fiber lengths from shortening. For OCC and BCTMP, gentle mechanical impacts on fibers using Hobart mixer increased breaking lengths and tear strengths simultaneously at fast drainage level, and straightening fibers using kady mill increased those strength properties further. For SwBKP and HwBKP, only mechanical impacts using the Hobart mixer were effective on increasing tensile and tear strength at fast drainage, but there were no further increase by kady mill treatment. The strength increases of BCTMP by this alternative fiber processing method were exceptionally high. An extensive engineering development should be followed to actualize this fiber processing mechanism in an energy-effect way.

Morphological features of thermophilic activated sludge treating food industry wastewater in MBR

  • Ince, Mahir;Topaloglu, Alikemal;Ince, Elif
    • Membrane and Water Treatment
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    • 제9권1호
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    • pp.33-42
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    • 2018
  • Microscopic examination of the activated sludge and morphological characterization of the flocs provides detailed information about the treatment process. The aim of this study is to investigate the morphological parameters of flocs obtained from a thermophilic jet loop membrane bioreactor (JLMBR) in different sludge retention times (SRTs), considering EPS and SMP concentration, hydrophobicity, zeta potential. The results showed that irregularity decreased with the increasing SRT. The compactness value was calculated to be less than 1 for all SRTs. However, the sludge had a more compact structure when the SRT increased. Zeta potential increased whereas hydrophobicity and floc size reduced, with increasing SRT. Furthermore, 2-D porosity calculated using the hole ratio was higher at greater SRTs. Hence, there was a significant correlation between the results obtained using the imaging technique and operation conditions of thermophilic JLMBR.

Hemicellulase 처리에 의한 목재 펄프의 고해 효과 변화 (Advanced Refining Effects of Wood Pulp Treated Hemicellulase)

  • 김병현;신광철
    • 한국인쇄학회지
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    • 제26권1호
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    • pp.113-124
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    • 2008
  • Viscosity of cellulose pulp was greatly decreased with endo-xylanase treatment but tiny decreased with exo-xylanase treatment. Change of freeness was greatly influenced with exo-xylanase treatment. The first stage of refining(5,000 revolution), freeness was greatly decreased with exo-xylanase treatment. After middle stage of refining(10,000 revolution) change of freeness was similar to endo-xylanase treatment. WRV(water retention value) was more effective exo-xylanas than endo-xylanase treatment. Interfiber bonding of cellulose fiber was disintegrated with exo-xylanse treatment.

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리사이클링 횟수에 따른 일차미세섬유와 이차미세섬유의 폴리아크릴아미드 흡착특성 변화 (Effects of Recycling on Adsorption Characteristics of Cationic Polyacrylamide onto Primary and Secondary Fines)

  • 주성범;이학래
    • 펄프종이기술
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    • 제31권2호
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    • pp.34-41
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    • 1999
  • Adsorption of cationic polyacrylamide dry strength resins onto the surface of papermaking fibers and fines is critical for their effective utilization. Since dry strength resins are frequently employed when recycled fibers containing a great deal of fines are used as a raw material, their adsorption characteristic onto the recycled fiber fines is of great importance. In this study, effects of recycling on adsorption characteristics of cationic polyacrylamide onto primary and secondary fines were examined. Never dried bleached hardwood kraft pulp was beaten and dried for recycling. In each recycling step the adsorption characteristic of a cationic PAM onto primary and secondary fines was evaluated by kjeldahl nitrogen analysis method. The influence of recycling on water retention value and carboxyl content along with the sheet density and tensile strength was examined. Secondary fines of never dried pulp adsorbed twice as much of C-PAM as the primary fines, however, the adsorption capacity of the secondary fines decreased rapidly during the course of recycling and showed lower adsorption capacily than primary fines.

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A New Fiber Processing Method

  • Seo, Yung-Bum;Lee, Chun-Han
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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    • pp.433-440
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    • 2006
  • A fiber processing method, which might be an alternative for conventional refining process, was introduced. The method consists of repetitive, gentle, mechanical impacts on fiber, and ensued fiber uncurling process. This method was very effective for OCC and BCTMP for increasing WRVs (water retention value) while keeping fiber lengths from shortening. For OCC and BCTMP, gentle mechanical impacts on fibers using Hobart mixer increased breaking lengths and tear strengths simultaneously at fast drainage level, and straightening fibers using kady mill increased those strength properties further. For SwBKP and HwBKP, only mechanical impacts using the mixer were effective on increasing tensile and tear strength at fast drainage, but not kady mill treatment. The strength increases of BCTMP by this alternative fiber processing method were exceptionally high. An extensive engineering development should be followed to actualize this fiber processing mechanism in an energy-effect way.

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Grafting of Casein onto Polyacrylonitrile Fiber for Surface Modification

  • Jia Zhao;Du Shanyi
    • Fibers and Polymers
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    • 제7권3호
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    • pp.235-240
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    • 2006
  • Polyacrylonitrile (PAN) fiber was grafted with casein after alkaline hydrolysis and chlorination reactions of the original fiber. The structures and morphologies of the casein grafted fiber were characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), and scanning electron microscope (SEM). Moisture absorption, specific electric resistance, water retention value, and mechanical properties were also investigated. The results showed that casein was grafted onto the surface of the PAN fiber and the grafted PAN fiber presented better hygroscopicity compared with the untreated fiber. With proper tensile strength, the modified fiber could still meet the requirement for wearing. A mechanism was proposed to explain the deposit of casein on the synthetic acrylic fiber.

첨가제를 병용한 섬유의 물리적 전처리의 효과 (Effect of Papermaking Additives on Fiber Mechanical Pretreatment)

  • 서영범;이민구;하인호;조욱연
    • 펄프종이기술
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    • 제35권4호
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    • pp.1-7
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    • 2003
  • In this study, fiber mechanical pretreatment before refining was executed with the addition of papermaking addiditives to find synergistic effects on fiber property improvement. Three fiber furnishes (SwBKP, KOCC, and BCTMP), and five different additives (CMC, CPAM, PEO, NaOH, $Na_2O_2$) were used. It was confirmed again that fiber mechanical pretreatment using Hobart mixer was a special way to modify fiber properties, where fiber WRV (water retention value) increases without losing fiber length. For SwBKP, addition of small amount of CMC (0.2% OD basis), and for KOCC, PEO (0.2% OD basis) caused additional significant improvement of the fiber furnish properties, respectively. Other additives did not cause adverse effects on the mechanical pretreatment, or better. For BCTMP, NaOH addition followed by mechanical pretreatment caused more than 20% improvement in tensile and tear strength simultaneously, compared to the control. The yellowing caused by the treatment of NaOH on BCTMP could be minimized by using $Na_2O_2$ without losing the positive effect of NaOH.

인후두역류질환의 진단 방법으로서 Water-Siphon Test의 유용성 (Effectiveness of Water-Siphon Test as A Diagnostic Test of Laryngopharyngeal Reflux)

  • 배소영;박혜상;박진영;백승연;장동혁;김수진;김소정;김한수;정성민
    • 대한후두음성언어의학회지
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    • 제23권2호
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    • pp.124-128
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    • 2012
  • Background and Objectives : There are many diagnostic modalities to evaluate laryngopharyngeal reflux. However, ideal diagnostic methods have not been established yet. The purpose of this study is to evaluate the effectiveness of Water-Siphon test as a diagnostic test of laryngopharyngeal reflux. Subjects and Methods : From November 2006 to September 2007, we performed esophagography with Water-Siphon test and questionnaire, physical examination for 227 patients with laryngopharyngeal reflux symptoms. The results of Water-Siphon test were classified according to the degree of reflux, the number of reflux, the retention time and analyzed about the relationship with the reflux symptom index (RSI), reflux finding score (RFS). Results : The degree of reflux was related with pseudosulcus, thick endolaryngeal mucus. The number of reflux was related with thick endolaryngeal mucus. A positive predictive value of Water-Siphon test was 82.7% and sensitivity was 91.5%. Conclusion : Water-Siphon test is a reliable diagnostic test for laryngopharyngeal reflux.

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Gum류를 첨가한 우육 Patty의 품질 특성 (Quality Characteristics of Beef Patty Containing Gums)

  • 정인철;김도완;이경수
    • 동아시아식생활학회지
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    • 제10권5호
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    • pp.404-404
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    • 2000
  • In order to investigate the possibility of low fat meat products, beef patties were prepared with gumssuch as carrageenan, methyl cellulose, and xanthan gum. The quality characteristics of beef patties were examined. Moisture contents of raw and cooked patties of control were lower than those of patties containing gums. and fat content was higher than those of containing gums. There was no significant difference in the protein contents of patties. In case of L-value(lightness) of raw patty, the control was higher than those patties containing gums. a- ( redness) and b-value(yellowness) among patties were not significantly different. Cooking yield, fat retention, and water holding capacity of beef patties containing gums were higher than control beef patty, but salt soluble protein and gel strength were not significantly different. Significant difference did not exist among beef patties in hardness, but the chewiness and gumminess of patties containing gums were higher than control. In case of sensory evaluation, there was no significant difference among patties in aroma and palatability. Texture of control was higher than patties containing gums, and juiciness of control was higher than patties containing carrageenan.

토양개량제(土壤改良劑) Uresol 및 Bitumen 처리(處理)가 토양(土壤)의 수분이동(水分移動)과 유실(流失)에 미치는 영향(影響) -I. 토양입단(土壤粒團)의 안정성(安定性)과 보수력(保水力) 변화(變化) (Effects of Soil Conditioner "Uresol and Bitumen" Treatment on Water Movement and Soil Loss -I. The Changes of the Aggregate Stability and the Moisture Retention)

  • 조인상;조성진
    • 한국토양비료학회지
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    • 제16권4호
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    • pp.294-300
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    • 1983
  • 토양개량제(土壤改良劑)가 토양구조(土壤構造)의 특성변화(特性變化)에 미치는 영향(影響)을 구명(究明)하기 위하여 친수성(親水性)인 Uresol과 소수성(疎水性)인 Bitumen을 사양토(砂壤土)와 미사질양토(微砂質壤土)에 각각(各各) 처리하여 토양입단(土壤粒團)의 물리적(物理的) 제특성(諸特性)을 분석(分析)한 결과(結果)는 다음과 같다. 1. Bitumen 0.4%, Uresol 0.6% 처리(處理)로 토양구조(土壤構造)의 안정성지수(安定性指數)는 처리(處理)하지 않은 토양(土壤) 0.275~0.416에 비(比)하여 1.650~3.450으로 현저히 증가(增加)되었으며 수중침적용적중(水中沈積容積重)은 크게 감소(減少)되었다. 2. 통기(通氣)-투수성(透水性) 비율(比率)은 사양토(砂壤土)에서 처리(處理)하지 않은 토양(土壤)이 3.8인데 비(比)하여 Uresol처리 토양은 2.2로 감소(減少)되었으며, 미사질양토(微砂質壤土)에서 무처리토양(無處理土壤)이 9.4인데 비(比)하여 Bitumen 처리토양(處理土壤)은 6.9, Uresol처리토양(處理土壤)은 5.3으로 낮았다. 3. 토양구조(土壤構造)의 불안정지수(不安定指數)가 증가(增加)될수록 통기(通氣)-투수성(透水性) 비율(比率)은 급격히 상승(上昇)되다가 지수(指數)가 1 이상(以上)에서는 이 비율(比率)이 매우 완만(緩慢)하게 증가(增加)되었다. 4. 친수성(親水性)인 Uresol처리(處理)는 토양(土壤)의 보수력(保水力)을 2~6% 증가(增加)시켰으나 소수성(疎水性)인 Bitumen 처리(處理)는 보수력(保水力)이 1~3% 감소(減少)되었다.

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