• Title/Summary/Keyword: Acid-treated

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Adsorption and Catalytic Characteristics of Acid-Treated Clinoptilolite Zeolite (산처리한 Clinoptilolite Zeolite 의 흡착 및 촉매특성)

  • Chon Hakze;Seo Gon
    • Journal of the Korean Chemical Society
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    • v.20 no.6
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    • pp.469-478
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    • 1976
  • Clinoptilolite zeolite samples were treated with hydrochloric acid, sulfuric acid and phosphoric acid of different strength and the adsorption characteristics and crystal structures of the original and acid-treated clinoptilolites were studied. By treating with hydrochloric acid, the adsorbed amount increased to 5-fold for nitrogen, to 3-fold for benzene, but for methanol no significant change was observed. As acid strength increased further, there were declines both in adsorption capacity and crystallinity. The results showed that the increase of adsorbed amount was caused by the rearrangement of the pore entrance and cation exchange. A method for determination of clinoptilolite content in natural mineral based on benzene adsorption on acid-treated sample is proposed. By this method, the original sample used in this study was found to contain approximately 40% of clinoptilolite. Using pulse technique in micro-catalytic reactor system, the catalytic activities of hydrochloric acid-treated clinoptilolites in cumene cracking and toluene disproportionation reactions were measured. For cumene cracking reaction, the maximum conversion was observed for the 0.5 N hydrochloric acid-treated sample. It is instructive to note that the maximum benzene adsorption was also observed for the sample treated with 0.5 N HCl. This suggest that the conversion rate was determined mainly by the rate of transport of reactants and the products through the pore structure. In the toluene disproportionation reaction, the same trend was observed. But the rate of deactivation was high for samples with strong acid sites. Since catalyst having higher activity was deactivated more easily, the conversion maximum was shifted to the sample treated with higher concentration of acid, -1N. The catalytic activity of $Ca^{2+} and La^{3+} ion exchanged samples for the toluene disproportion was much lower than that of acid-treated samples. Introduction of Ca^{2+} and La^{3+}$ into the pore structure apparently decreases the effective pore diameter of acid-treated clinoptilolite thus limiting the diffusion of reactants and products.

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A Study on Tannin Treatment of silk fabrics(II) - The effect of mordants - (견의 탄닌처리에 관한 연구(II) - 매염제의 영향을 중심으로 -)

  • 설정화;최석철
    • Textile Coloration and Finishing
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    • v.6 no.2
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    • pp.1-9
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    • 1994
  • In order to study the effect of mordanting on silk fabrics treated with tannin, those fabrics were treated with Al, Cu, Cr, Fe, Sn by pre and post mordanting. It was studied about color change, weighting effect, dgree of photodegradation by pre and post mordanting. The results are as fallows ; 1. On the addition of mordants into mimosa and tannic acid solution, &{\lambda}_{max}& of the former was slightly blue-shifted, on the other hand, &{\lambda}_{max}& of the latter was obviously Red-shifted. 2. In case of Cu, Cr, Pre mordanting, weighting effect were appeared. Weighting effect of silk fabrics treated with Tannic acid increased higher than mimosa by mordanting. 3. In color change, Silk fabrics treated with Mimosa and Tannic acid generally changed to red direction and fabrics treated with tannic acid changed to yellow direction by pre and post mordanting. 4. In the photodegradation, the degree of photodegradation on mordanted fabrics increased. Its degree was slack in Cu, Cr, Post mordanting. On the other hand, Al, Fe, Sn were greate. Silk fabrics treated with Mimosa and Tannic acid got inhibiting effect on photodegradation.

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Microbiological, PH and Sensory Evaluations of Refrigerated Pork Loins Treated with Lactococcus lactis ATCC l1454 (Lactococcus lactis ATCC 11454로 처리한 냉장 돼지고기 등심의 미생물, pH 및 관능평가)

  • 김창렬;김광현;이재일
    • The Korean Journal of Food And Nutrition
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    • v.14 no.2
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    • pp.126-131
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    • 2001
  • Microbiological, pH and sensory evaluations of pork loins treated with lactic acid cultures (Lactococcus lactis subsp. lactis ATCC 11454 grown in 10% milk solids) during storage at 4$^{\circ}C$ were assessed. Pork loins were immersed in solutions containing 3.96 log units, 4.10 log units, or 4.23 log units of individual lactic acid cultures for 2 min. Pork loins treated with lactic acid cultures had a inhibitory effect (P<0.05) on the growth of aerobic palate counts during storage of 3 days at 4$^{\circ}C$. Pork loins treated with lactic acid cultures during storage of 3 days at 4$^{\circ}C$ significantly (P<0.05) decreased pH values compared to those of controls. Sensory evaluations for odor and appearance of pork loins treated with lactic acid cultures during storage of 9 days at 4$^{\circ}C$ were a "liked less" to "typical" category compared to those of controls.

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Hydrolysis of the Ester Crosslink on Cotton Fabric Treated with Combination of Poly(maleic acid) and Citric Acid (Poly(maleic acid)/Citric Acid 혼합 처리면포의 Ester 가교결합의 가수분해)

  • Kang In-sook;Bae Hyun-sook
    • Textile Coloration and Finishing
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    • v.17 no.3 s.82
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    • pp.16-25
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    • 2005
  • In this research, we investigated hydrolysis of the ester crosslinking on cotton fabric treated with polymer of maleic acid(PMA), citric acid(CA) and combination of polymer of maleic acid and citric acid using Fourier transform infrared spectroscophy. The rate of hydrolysis of the ester crosslinkage increased with pH regardless of the type of polycarboxylic acid used and even after hydrolysis for 256 hour in pH 13_4 solution, the treated fabric retained $10-20\%$ ester crosslinkage. The durability to alkaline hydrolysis of the ester crosslinkage formed by CA was lower than that of by PMA and combination of poly(maleic acid) and citric acid indicating that the ester formed by CA on the cotton fabric is more susceptible to hydrolysis than that formed by PMA and combination of PMA and CA. The total amount of ester and polycarboxylic acid molecules removed from fabric increased with increasing hydrolysis time but the rate of hydrolysis of ester linkage were higher than that of removal of polycarboxylic acid molecule from the fabric. The characteristic of hydrolysis of fabric treated with combination of PMA and CA was related with the mixing ratio of PMA and CA in treating fabric.

Approach to Develop the New Treatment Methodologies of Grass Silage to Enhance the Feed Nutritive value by Ruminant (조사료자원의 처리가공 기술개발에 관한 연구 - 산 또는 당류처리에 의한 화본과목초의 사료가치 증진시험)

  • 홍병주;고용균
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.11 no.1
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    • pp.43-52
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    • 1991
  • The overall objective of this research was to evaluate the effects of spraying sulfuric acid solution, and adding corn meal or molasses to reed canarygrass silage on digestibility of dry matter (DM) and fibrous components in ruminant. DM content of molasses or corn meal treated silages were higher than control. Whereas, sulfuric acid treated silage showed lower DM content compared with untreated control. Acid detergent fiber content was similar among treatments, but neutral detergent fiber (NDF) and hemicellulose concentration were higher in treated silages than those of control. Organic acids content were also increased in treated silages. In contrast, silage pH were lower in treated silages. Treated silages increased both rate and extent of DM and NDF in situ digestibility compared to control at all incubation times. Especially, 7 % molasses and 0.4 % sulfuric acid treated silages increased DM and NDF digestibility significantly after 12 hours of incubation compared with control. In nitro DM and NDF digestibility showed similar trend to in situ incubation. Also treated silages(mo1asses or sulfuric acid treated) incubated in situ had higher particle-associated carboxymethylcellulase activity throughout the incubation except 72 hours.

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Action of ${\alpha}$-Amylase and Acid on Resistant Starches Prepared from Normal Maize Starch

  • Lim, Jin-Woo;Mun, Sae-Hun;Shin, Mal-Shick
    • Food Science and Biotechnology
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    • v.14 no.1
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    • pp.32-38
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    • 2005
  • Effects of acid and ${\alpha}$-amylase on resistant starches including retrograded RS3 and cross-linked RS4 prepared from normal maize starch were investigated. Acid and ${\alpha}$-amylase hydrolytic patterns of RS3 were similar, while those of native starch and RS4 differed. Acid hydrolysis rate of RS3 was markedly higher at initial stage, then slowly decreased up to 20 days, whereas that of RS4 increased continuously. The sizes of acid- and ${\alpha}$-amylase-treated RS3 residues decreased, but those of RS4 remained unchanged. X-ray patterns of all treated residues did not change; however, the peak intensities increased. Swelling power of RS3 increased to 150% at $95^{\circ}C$, whereas that of RS4 differed depending on the treatment condition. Swelling power of acid-treated RS4 residue increased markedly, but that of ${\alpha}$-amylase-treated one remained constant. Gel filtration chromatography profiles of untreated RS3 and RS4 residues were similar, whereas that of acid-treated RS4 residue was different from them. RS showed different hydrolytic behavior by acid and ${\alpha}$-amylase depending on the type, and susceptibility of RS3 was higher than that of RS4.

Effect of 2,4-Dichlorophenoxyacetic Acid (2,4-D) and Naphthoxyacetic Acid (NOA) on the Biochemical Changes in the Fat Body and Haemolymph of the Silkworm, Bombix mori L.

  • Goudar, K.S.;Kaliwal, B.B.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.3 no.1
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    • pp.7-11
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    • 2001
  • The effect of topical application with 200,400 and 600 $\mu$g/ml 2,4-Dichlorophenoxyacetic Acid (2,4-D) and Naphthoxyacetic Acid (NOA) to the fifth stadium larvae of the silkworm, B. mori on fat body glycogen, protein, total lipids, phospholipids, neutral lipids and haemolymph trehalose and protein has been studied. The fat body glycogen significantly increased in all the groups treated with 2,4-D whereas there is no significantly change in fat body glycogen in all the groups treated with NDA. However, the haemolymph trehalose was significantly increased in all 274-D and NOA treated groups except in the groups treated with 400 and 600 $\mu$g/ml 2,4-D where the increase was not significant.The fat body protein did not show any significant change in all groups treated with 2,4-D and NOA except in the groups treated with 200 $\mu$g/ml 2,4-D where the fat body protein was significantly increased. The total lipids, phospholipids and neutral lipids of the fat body increased significantly in all the groups treated with 2,4-D and NOA when compared with those of the corresponding parameters of the carrier control.

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Utilization of Ligno-cellulosic Biomass(III)-Acid Hydrolysis of Exploded Wood after Delignification (목질계 바이오매스의 이용(제3보)-탈리그닌 처리한 폭쇄재의 산가수분해-)

  • 양재경;장준복;임부국;이종윤
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.4
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    • pp.18-27
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    • 1997
  • This study was performed to obtained the optimal delignified condition of exploded wood on the acid hydrolysis with sulfuric acid. Wood chips of pine wood(Pinus desiflora), oak wood(Quercus serrata) and birch wood (Betula platyphylla var. japonica) were treated with a high pressure steam (20-30kgf/$\textrm{cm}^2$, 2-6 minutes). The exploded wood was delignified with sodium hydroxide and sodium chlorite, and then hydrolyzed with sulfuric acid. The result can be summerized as follows ; In the exploded wood treated with sodium hydroxide, the optimal concentration of sodium hydroxide was 1% as content of lignin in the exploded wood. Lignin content of exploded wood treated with sodium chlorite was lower then that sodium hydroxide. The maximum reducing sugar yield of exploded wood treated with 1% sodium hydroxide was lower than non-treated exploded wood. In the case of sodium chlorite treated, the maximum reducing sugar yield was hgher than non-treated exploded wood. Sugar composition of acid hydrolysis solution was composed of xylose and glucose residue, and the rate of glucose residue was increased in high pressure condition.

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Effects of Pre-Converted Nitrite from Red Beet and Ascorbic Acid on Quality Characteristics in Meat Emulsions

  • Choi, Yun-Sang;Kim, Tae-Kyung;Jeon, Ki-Hong;Park, Jong-Dae;Kim, Hyun-Wook;Hwang, Ko-Eun;Kim, Young-Boong
    • Food Science of Animal Resources
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    • v.37 no.2
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    • pp.288-296
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    • 2017
  • We investigated the effects of fermented red beet extract and ascorbic acid on color development in meat emulsions. The pH of meat emulsions containing red beet extract decreased with an increase in the amount of extract added. The redness of the treated meat emulsions was higher than that of the control with no added nitrite or fermented red beet extract (p< 0.05), though the redness of the meat emulsions treated with fermented red beet extract only was lower than in that treated with both fermented red beet extract and ascorbic acid (p<0.05). The highest VBN, TBARS, and total viable count values were observed in the control, and these values in the meat emulsions treated with fermented red beet extract were higher than in that treated with both fermented red beet extract and ascorbic acid (p<0.05). E. coli and coliform bacteria were not found in any of the meat emulsions tested. Treatment T2, containing nitrite and ascorbic acid, had the highest overall acceptability score (p<0.05); however, there was no significant difference between the T2 treatment and the T6 treatment, which contained 10% pre-converted nitrite from red beet extract and 0.05% ascorbic acid (p>0.05). The residual nitrite content of the meat emulsions treated with ascorbic acid was lower than in those treated without ascorbic acid (p<0.05). Thus, the combination of fermented red beet extract and ascorbic acid could be a viable alternative to synthetic nitrite for the stability of color development in meat emulsions.

Mechanical Properties of Cotton Fabric Treated with Succinic Acid - Tear Strength - (Succinic Acid 처리면포의 역학 특성 - 인열강도 -)

  • Kang, In-Sook;Bae, Hyun-Sook
    • Textile Coloration and Finishing
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    • v.21 no.3
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    • pp.1-9
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    • 2009
  • Polycarboxylics acids are used as crosslinking agents for cotton cellulose to produce durable finished press cotton fabric. It has been observed that the strength of the cotton fabric treated with polycarboxylic acids showed significant reduction as a result of the crosslinking process. The effect of acid-catalyzed depolymerization on the tear strength of cotton fabric is investigated by evaluating the cotton fabric treated by succinic acid, which does not crosslink cotton cellulose and form little ester on the cotton fabric. We find that the tear strength of cotton fabric treated with succinic acid decreases at elevated temperature due to acid-catalyzed depolymerization of cellulose. The magnitude of fabric strength reduction increases as the acid concentration increases. At a constant acid concentration, it increases as the curing temperature and time increases. It decreases as the pH of the acid solution increases. We also find that the dissociation constant of an acid also has a significant effect on the fabric strength reduction. The magnitude of fabric tear strength reduction increases as the acid dissociation constant decreases.