• Title/Summary/Keyword: Ammonia swelling

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Effects of Ammonia Swelling Treatment in Carboxymethylation of Domestic Kraft Pulp on Characteristics of Corboxymethylcellulose(CMC) and CMC Solution (국산(國産) 크라프트 펄프의 카르복시메틸화시(化時) 암모니아 팽윤처리(膨潤處理)가 카르복시메틸셀룰로오스와 카르복시메틸셀룰로오스 용액(溶液)의 특성(特性)에 미치는 효과(效果))

  • Ahn, Byoung-Kuk;Ahn, Won-Yung
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.2
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    • pp.25-35
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    • 1990
  • To investigate the effects of swelling treatment by ammonia on characteristics of carboxymethy1cellulose(CMC) and CMC solution, the domestic kraft pulp pretreated with 5%, 10%, 15% and 20% $NH_4OH$ solution, was carboxymethylated by the standard method, and then the CMC prepared was tested. The physical properties of CMC and CMC solution, such as degree of substitution, transparency. viscosity, weight increase and solubility, were measured, and the comparison with commercial domestic CMC used as a food additive was done. The results obtained were as follows; 1. In CMC manufactured by standard solvent method, hardwood bleached kraft pulp(LBKP) was more substituted than safwood bleached kraft pulp(NBKP), and viscosity of NBKP was higher than that of LBKP. 2. When ammonia swelling treatment was done, degree of substitution gradually decreased with increasing concentration of $NH_4OH$, and degree of substitution of LBKP decreased with a larger range than that of NBKP. 3. When ammonia swelling treatment was done. transparency of CMC solution from LBKP was hardly effected, but in case of NBKP gradually increased with increasing concentration of $NH_4OH$. 4. When ammonia swelling treatment was done, viscosity of CMC solution was higher than that of CMC solution without ammonia swelling treatment. Especially, CMC of high viscosity could be manufactured in 5%, 10% concentration levels of $NH_4OH$. 5. In CMC manufactured from domestic NBKP, CMC at the range of 0.40 to 0.50 in DS was dispersed easily and quickly dissolved, and CMC at more than 0.50 in DS was dispersed slowly in water solution. 6. In comparison with commercial domestic CMC used as a food additive, CMC manufactured from domestic NBKP was higher in DS, and was lower in viscosity and transparency.

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Fine Structure and Physical Properties of Cotton Fibers and their Fabrics Treated with Liquid Ammonia, NaOH, and NaOH/Liquid Ammonia (액체암모니아, 수산화나트륨, 수산화나트륨/액체암모니아 처리한 면의 미세구조 및 물성)

  • 배소영;이문철;김홍성;이영희;김경환
    • Textile Coloration and Finishing
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    • v.6 no.2
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    • pp.47-54
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    • 1994
  • Cotton fiber, NaOH-mercerized cotton fiber, cotton fabric, and NaOH-mercerized cotton fabric have been treated by liquid ammonia at -33.4$^{\circ}C$. The fine structures, bending properties, tensile strengthes, shrinkages for laundering, and wrinkle recoveries were studied. The treatment of cottons with liquid ammonia brought about the transition of crystal lattice ; transforming cellulose I crystal of original cotton to cellulose I and III crystal, and cellulose II crystal of mercerized cotton to cellulose II and III crystals. The degree of crystallinities were decreased in the order of liquid ammonia>NaOH/liquid ammonia>NaOH-treated cotton. However moisture regain and water absorbency for liquid ammonia-treated cotton were lower than that of NaOH-treated cotton because of a difference in swelling actions of the agents. It seems caused by intermicrofibrillar pores produced in swelling processes. The bending rigidity and bending hysteresis were decreased remarkly by liquid ammonia treatment. Therefore softness and dimensional stability were improved. The liquid amminia and NaOH/liquid ammonia-treated cottons moreover show excellent properties in tensile strength, anti-shrinkage for laundering, and wrinkle recovery.

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Design Using Bent Wood Plasticized with Liquid Ammonia (액체암모니아 휨가공 소재를 응용한 디자인)

  • 강호양;강형구
    • Journal of the Korea Furniture Society
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    • v.12 no.2
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    • pp.11-18
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    • 2001
  • Steaming has been used for bending wood for a long time, but the steam-bent wood is subject to spring-back and a relatively large radius of curvature. Liquid ammonia is known as an excellent wood plasticizer swelling both crystal and amorphous cellulose. Liquid ammonia technique for wood plasticization was developed and applied for bending alder and padauk pieces, which were used as parts of wooden furniture. The study confirmed that liquid ammonia bent wood can be used for various wood working design.

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Properties of Bentwood for Esthetic Designing by Microwave and Ammonia Solution Treatment

  • Lee, Won-Hee;Bae, Hyun-Mi
    • Journal of the Korea Furniture Society
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    • v.18 no.4
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    • pp.275-281
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    • 2007
  • This study was carried out to know bending process property of bentwood by treatment methods such as microwave and ammonia solution treatment. Bentwood processing was operated on bending-jig form with 60mm and 100mm radius of curvature (ROC). The species was used to Korean red pine (Pinus densiflora). No significant difference was shown in bentwood processing method on ROC. In treatment method, ammonia solution treatment for bentwood was better in dimensional stability and working ability than that of microwave treatment. However, bentwood stress was reduced with ammonia solution treatment. Color of bentwood surface appearance has a dark tendency in ammonia solution treatment. But it seems to beautiful effect of apparent annual ring is rising esthetically by ammonia solution treatment. To utilize wood as a exterior material for living amenity, it has to be closely examined from various angles including surface property, degree of swelling and shrinkage, drying state, retaining strength, durability, safety, and insect damage.

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A Study on the Tension and Slack Mercerization of Cotton Fabrics (견직물의 긴장과 무긴장머어서화 가공에 관한 연구)

  • Chul-Ho, Choi;Chan-Min, Lee
    • Textile Coloration and Finishing
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    • v.2 no.3
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    • pp.51-58
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    • 1990
  • Cotton fabrics were mercerized in ammonia water, sodium hydroxide and mixture of ammonia/sodium hydroxide, slack and under tension. X-ray and infrared spectra analyses were used to measure crystallinity of treated cottons. Changes due to swelling, which took place in the accessible regions were determined by moisture regain and dye adsorption. In addition to that crease recovery was compared mutually, and breaking strength-elongation compared, too. Both ammonia water and caustic treatments produced changes in morphology (swollen fibers, decrease in convolutions) and in fine structure of the cellulose (increase accessibility as measured by increased moisture regain, dye adsorption). X-ray diffraction showed partial recrystallization into cellulose III lattic after tension treatment with ammonia water. Both reagents produced increased cotton elongation-at-break with slack mercerization, increased cotton breaking strength with tension mercerization, and increased moisture regain or dye adsorption with slack mercerization.

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Pretreatment Characteristics of Ammonia Soaking Method for Cellulosic Biomass (암모니아 Soaking 방법을 이용한 섬유소계 바이오매스의 전처리 특성)

  • Park, Yong-Cheol;Kim, Jin-Woo;Kim, Jun-Seok
    • Korean Chemical Engineering Research
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    • v.49 no.3
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    • pp.292-296
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    • 2011
  • Liberation of fermentable sugars from lignocellulosic biomass is one of the key challenges in production of cellulosic ethanol. Aqueous ammonia cleaves ether and ester bonds in lignin carbohydrate complexes. It is an effective swelling reagent for lignocellulosic biomass. The aqueous ammonia pretreatment selectively reduces the lignin content of biomass. However, at high temperatures, this process solubilizes more than 50% of the hemicellulose in the biomass. Here we conducted a SAA(Soaking in Aqueous Ammonia) process by moderate reaction temperatures at atmospheric pressure using various lignocellulosicbiomass. The optimum condition of this process was 15 wt% of aqueous ammonia at 50 of reaction time during 72 hr. The delignification was up to 60% basis on initial biomass and the enzymatic digestibility was 60-90% for agricultural biomass, respectively.

Renal replacement therapy in neonates with an inborn error of metabolism

  • Cho, Heeyeon
    • Clinical and Experimental Pediatrics
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    • v.62 no.2
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    • pp.43-47
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    • 2019
  • Hyperammonemia can be caused by several genetic inborn errors of metabolism including urea cycle defects, organic acidemias, fatty acid oxidation defects, and certain disorders of amino acid metabolism. High levels of ammonia are extremely neurotoxic, leading to astrocyte swelling, brain edema, coma, severe disability, and even death. Thus, emergency treatment for hyperammonemia must be initiated before a precise diagnosis is established. In neonates with hyperammonemia caused by an inborn error of metabolism, a few studies have suggested that peritoneal dialysis, intermittent hemodialysis, and continuous renal replacement therapy (RRT) are effective modalities for decreasing the plasma level of ammonia. In this review, we discuss the current literature related to the use of RRT for treating neonates with hyperammonemia caused by an inborn error of metabolism, including optimal prescriptions, prognosis, and outcomes. We also review the literature on new technologies and instrumentation for RRT in neonates.

Effect of Processing and Reactive Dyeing on Swelling and Pore Structure of Lyocell Fibers

  • Sasaki, Hiroaki;Donkai, Nobuo;Kasahara, Katusji
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.33-34
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    • 2003
  • Lyocell yarns were treated with NaOH, liquid ammonia, high pressure steam and polycarboxylic acids, and dyed with five reactive dyes. The water content of the samples was also measured by the centrifugal and chromatographic techniques. The total pore volume w as substantially increased by NaOH treatment, while decreased by high pressure steaming. The pore size distributions for the dyed samples were affected by the dyes used.

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Studies on the artificial infection and the hematological change with Fasciola hepatica metacercariae in rats (흰쥐에 대(對)한 간질피낭유충(肝蛭被囊幼蟲)의 인공감염(人工感染)과 혈액상(血液像)에 관(關)한 연구(硏究))

  • Kang, Seung-won
    • Korean Journal of Veterinary Research
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    • v.34 no.3
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    • pp.549-557
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    • 1994
  • This study was done to find the method of the extermination of Fasciola hepatica matacercariae. And the artificial infection was carried out with 30 metacercarae exposed to 5% ammonia water and not-exposed to 5% ammonia water. Serial determinations of live weight, red blood cell, hemoglobin, packed cell volume, and eosinophils were performed in rats at 7 days interval for 16 weeks after infection (WAI). Recovery of worm burden and microscopic findings of livr was performed in rats at 10 WAI. The results in this work were summarized as follows; 1. Fasciola spp metacercariae exposed to 5% ammonia water have lost their ability of infection. 2. In teh exposed group, the mean of worm recovered was 2.25 and the common bile duct was swelling up to 0.71cm in diameter. 3. The value of live weight was different in two groups as the not-exposed group and the exposed group were 321.28, 384.38 at 10 WAI, respectively. 4. In the not-exposed group, at 7 WAI, hemoglobin at 5 WAI and packed cell volume at 7 WAI wre minimally decreased to $5.84{\times}10^{-6}/mm^3$, 11.53g/dl and 43.2%, respectively. But those three values were slowly increased at 10 WAI. Rercent cosinophil was increased to 12.2% at 4 WAI and slightly decreased to 7.9% at 10 WAI. But there are no stastistical singnificance between the exposed group and the normal control group. 5. In histolgical findings in the not-exposed group, the dilated common bile ducts and intrahepatic bile ducts showed distinct hyperplasia of the epithelium. Lymphocytes and eosinophils were infilterated around the bile ducts. The hepatic cells and Kupffer cells showed swollen appearance.

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Synthesis of Sulfonated POF-g-Styrene ion Exchange Fibers by Radiation-Induced Polymerization and Properties of Ammonia Adsorption (방사선 중합에 의한 설폰화 POF-g-Styrene 이온교환 섬유의 합성 및 암모니아 흡착)

  • Cho, In-Hee;Baek, Ki-Wan;Lee, Chang-Soo;Nho, Young-Chang;Yoon, Soo-Kyung;Hwang, Taek-Sung
    • Polymer(Korea)
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    • v.31 no.1
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    • pp.1-7
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    • 2007
  • In this study, the sulfonated ion exchange fiber was synthesized by $Co^{60}\;{\gamma}-ray$ radiation-induced graft copolymerization. Degree of grafting (DG) increased with increasing the total dose and showed the highest value at 50 v/v% styrene monomer. And also, the degree of sulfonation (DS) increased with increasing the DG and reaction temperature. DS showed the maximum value at 20 min. Ion exchange capacity and swelling ratio of ion exchange fibers increased with increasing the DS and their maximum values were 4.76 meq/g and 23.5%, respectively. Ammonia adsorption increased as increasing the ammonia concentration and ion exchange capacity and remained constant over 10 cycles.