• Title/Summary/Keyword: OH value

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Effect of Acid and Salt on Weight toss of Polyester (PET) fabric by Sodium Hydroxide (산과 염이 폴리에스터 직물의 알칼리 감량에 미치는 영향)

  • Do, Sung-Guk;Cho, Hwan
    • Textile Coloration and Finishing
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    • v.4 no.3
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    • pp.65-73
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    • 1992
  • To control the hydrolysis rate of PET fabric with NaOH, HCl and $CH_3$COOH(HAc), as regulating reagent, were added to the 0.5 M NaOH solution. The concentrations of acids in 0.5 M NaOH were varied. PET fabrics were treated with aqueous solutions of acids in 0.5 M NaOH under different conditions. The weight loss of PET fabric, the rate of hydrolysis, the apparent activation energy (E$_{\alpha}$), the handle value, the etched surface of treated PET fabric, and the effect of salts such as NaCl, $CH_3$COONa(NaAc), and NH$_4$Cl on the weight loss were discussed. Acids in the aqueous 0.5 M NaOH solution decreased the weight loss of PET fabric bacause of neutralization of OH- and the weight loss of PET fabrics treated with corresponding concentration of aqueous NaOH solution to the concentrations of the aqueous solutions of acids in 0.5 M NaOH was lower than that of PET fabrics treated with aqueous solutions of acids in 0.5 M NaOH. The addition of NaCl to aqueous NaOH solution accelerated the reaction of OH- with PET greatly, the addition of NaAc increased the weight loss slightly, but the addition of NH$_4$Cl decreased the weight loss. It was thought that the very remarkable result that NaCl in aqueous NaOH solution promoted the hydrolysis of PET with NaOH would contribute to the conservation of energy and NaOH in the weight loss finishing process of PET fabric. The etched surface and the handle value of treated PET fabric were independent of the difference in the kinds of acids and salts added.nd salts added.

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Changes in Fiber Characteristics by Low Concentration Sodium Hydroxide Swelling and Beating (저농도 NaOH 팽윤과 고해에 따른 섬유특성 변화)

  • Kim, Ah-Ram;Choi, Kyoung-Hwa;Cho, Byoung-Uk
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.3
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    • pp.65-72
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    • 2014
  • In this study, effects of alkali swelling at low concentration below 2 percent on properties of hardwood bleached kraft pulp (HwBKP) were elucidated. Swelling treatment of HwBKP was performed at various NaOH concentrations with/without beating. Then, the swelling characteristics of pulp fiber was evaluated by measuring the solvent retention values such as water retention value (WRV) and isopropyl alcohol retention value (LRV). It was found that fiber characteristics were influenced by NaOH swelling even at low alkali concentration and beating treatment as well. The values of WRV and LRV were decreased when the alkali concentration was increased. It is the result from the decreased acidic groups of pulp which were formed during beating. The acidic groups could be neutralized and then removed by alkali. The difference between WRV and LRV was decreased with increasing alkali concentration while the difference was increased when the alkali swollen pulp was beaten. In addition, the crystalline structure of HwBKP was almost not changed while the crystallinity was influenced by swelling treatment at a low alkali concentration.

Influence of Food Allowance on Nutrient Utilization of Oat (Avena sativa) Hay by Goats and Feeding Value of Leftovers from High Levels of Offer in Sheep

  • Dutta, N.;Sharma, K.;Hasan, Q.Z.;Pathak, N.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.5
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    • pp.723-727
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    • 1999
  • Two experiments were conducted to determine the effect of feeding levels on intake and nutrient utilization of oat (Avena sativa) hay (OH) by goats and potential feeding value of leftovers from high levels of offer in sheep. In experiment 1, the goats (15) were offered OH at three levels of feeding to give leftovers of about 20% (T-1), 35% (T-2) and 50% (T-3) of DM offered. A marked effect of refusal rate of OH on intake and digestibility of nutrients was evident. Allowing selective consumption at higher levels (T-2 and T-3), the intake of DCP and TDN from OH was found not only to meet the maintenance requirement but provided surplus nutrients for moderate production. In experiment 2, Sheep (3) were offered one of the three dietary treatments viz OH, refusals left uneaten by goats in T-2 and T-3 (OHR) and 3% urea treated oat hay refusals (UTR) in a $3{\times}3$ latin square design. Though the potential feeding value of leftovers (OHR and UTR) was lower than OH, the results confirm the possibility of their effective use. It was concluded that feeding above the conventional ad libitum level could be an alternative to improve the performance of ruminants fed feeds like oat hay. The potential impact of the strategy would, however, depend on the effective reutilization of leftovers for feeding other animals.

Study of Color Evolution by Silica Coating and Etching based Morphological Control of α-FeOOH (실리카 코팅과 에칭에 의한 α-FeOOH의 색상변화 연구)

  • Lee, NaRi;Yu, Ri;Kim, YooJin
    • Journal of Powder Materials
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    • v.25 no.5
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    • pp.379-383
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    • 2018
  • Silica is used in shell materials to minimize oxidation and aggregation of nanoparticles. Particularly, porous silica has gained attention because of its performance in adsorption, catalysis, and medical applications. In this study, to investigate the effect of the density of the silica coating layer on the color of the pigment, we arbitrarily change the structure of a silica layer using an etchant. We use NaOH or $NH_4OH$ to etch the silica coating layer. First, we synthesize ${\alpha}-FeOOH$ for a length of 400 nm and coat it with TEOS to fabricate particles with a 50 nm coating layer. The coating thickness is then adjusted to 30-40 nm by etching the silica layer for 5 h. Four different shapes of ${\alpha}-FeOOH$ with different colors are measured using UV-vis light. From the color changes of the four different shapes of ${\alpha}-FeOOH$ features during coating or etching, the $L^*$ value is observed to increase and brighten the overall color, and the $b^*$ value increases to impart a clear yellow color to the pigment. The brightest yellow color was that coated with silica; if the sample is etched with NaOH or $NH_4OH$, the $b^*$ value can be controlled to study the yellow colors.

Production of Biodiesel from High Acid Value Oils using Amberlyst-15 (Amberlyst-15를 이용한 산가가 높은 유지로부터 바이오디젤의 생산)

  • Sim, Yeon-Ju;Kim, Eui-Yong
    • KSBB Journal
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    • v.25 no.5
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    • pp.483-489
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    • 2010
  • Biodiesel has attracted great attention as an alternative renewable energy source for the replacement of petroleumbased diesel fuel, yet its high production cost due to expensive oil feedstock remainsas the major economical obstacle. In this study, we investigated catalysts and reaction conditions for the acid catalyzed pre-conversion of free fatty acid (FFA) to fatty acid methyl ester (FAME) in cheap low-grade oils of high acid value. The NaOH base catalyzed reaction of vegetable oil of the initial acid value of 2 mg KOH/g led to a high FAME conversion above 95.4%, but the conversion abruptly decreased at higher initial acid values. This base catalyzed reaction was practically ineffective displaying the FAME conversion below 15% even at the initial acid value of 10 mg KOH/g by the severe saponification side reaction. Among the various catalysts studied for the pre-conversion of FFA to FAME, Amberlyst-15 was the most effective in reducing the acid value, and the optimum reaction condition identified was $65^{\circ}C$ with oil to methanol ratio of 1:3 and catalyst concentration of 15% (w/w). As the results, great enhancements in the overall biodiesel conversion were achievable via a consecutive reaction of the acid catalyzed FFA pre-conversion to FAME under the optimal condition obtained with Amberlyst-15 followed by the NaOH base catalyzed reaction, far above the extent which was obtainable by the single NaOH catalyzed reaction.

Increasing Effect on Storage Stability of Rosemary Extracts used for Various Solvent System on Seasoning Oils (향미유 제품에 대한 추출 용매별 로즈마리 추출물의 저장 안정성 향상 효과)

  • Lee, Jang-Woo;Ahn, Young-Soon;Hong, Young-Pyo;Han, Myung-Kyu
    • The Korean Journal of Food And Nutrition
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    • v.19 no.3
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    • pp.271-278
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    • 2006
  • As for red pepper seasoning oil (RPSO), seasoning oil (SO) and pine needle oil (PNO), various organic solvent extracts from rosemary powder and tocopherol are treated as control group. At this time, amounts that are treated were all 1,000 ppm. It was observed by AV (acid value), POV (peroxide value) and carbonyl compounds content of the stored samples during 3 months at 60${\pm}$2$^{\circ}C$ incubation. Tocopherol was shown to be pro-oxidant than the antioxidant in all seasoning oil samples. Icreasing effect of storage stability of chloroform/MeOH extract was the most superior one. Final result of icreasing effect of storage stability from the determinated data was as follows. The storage stability of solvent system by AV and POV analysis was in the increasing order of chloroform/MeOH extract> ethyl alcohol extract>hot water extract>ethyl acetate extract>acetone extract>none treating group> tocopherol treating group, POV was chloroform/MeOH extract>ethyl alcohol extract ${\geq}$ ethyl acetate extract> acetone extract ${\geq}$ hot water extract>none treating group>tocopherol treating group and by carbonyl compound content analysis was in the increasing order of chloroform/MeOH extract>ethyl acetate extract>ethyl alcohol extract>hot water extract>acetone extract>none treating group>tocopherol treating group.

A Study of Ferrite Formation by Aerial Oxidation of Fe$(OH)_2$ Suspension of Aqueous Solution Containing Heave Metal Ions (水酸化鐵 懸濁液에서 空氣酸化에 의한 중금속이온의 Ferrite 생성에 관한 연구)

  • Lee, Sung Ho;Hyun, Yong Bum;Kim, Soo Saeng
    • Journal of Environmental Health Sciences
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    • v.12 no.1
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    • pp.1-14
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    • 1986
  • This investigation was carried out on the study of Ferrite formation by aerial oxidation of Fe $(OH)_2$ suspension of aqueous solution containing heavy metal ions. In this study the optimum reactionary condition of the Ferrite formation in Batch reactor wa studied by aerial oxidation which are subjected to various reaction time and temperature, under the different kinds of R(2NaOH/$FeSO_4$) Values, pH, Air flow rate, and $Fe^2+/M^2+$ mole ratio. The optimum condition for the Ferrite formation in Batch reactor was such that residence Time was 90 min., Temperature $65{\circ}$C, pH 11.0, Air flow rate 2.0l/min and $Fe^{2+}/M^{2+}$ mole ratio 4.0, which was observed by X-Ray diffraction analysis. The relation R-value, pH and ORP affecting the formation of Ferrite is that the jump step in pH 11.0, when a amount of NaOH is added, is steady state to the formation of Ferrite. Effect of R-value of $FeSO_4$ and $FeCl_2$ on the formation of Ferrite in different from each other the optimum condition of the in different from each other the optimum condition of the $FeCl_2$ is R-value 0.7, pH 11.0 and the $FeSO_4$ R-value 1.2, pH 11.0.

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Effects of Hyperoxia on 8-Hydroxydeoxyguanosine Formation in Carbon Monoxide Exposed Rats (일산화탄소 중독시 고압산소투여가 8-hydroxydeoxyguanosine 생성에 미치는 영향)

  • Kim, Heon;Cho, Soo-Hun;Chung, Myung-Hee
    • Journal of Preventive Medicine and Public Health
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    • v.27 no.1 s.45
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    • pp.84-106
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    • 1994
  • Hyperbaric oxygen (HBO) therapy for carbon monoxide (CO) poisoning eventually inducing the hypoxia-reoxygenation condition, may produce oxygen free radicals, which forms 8-hydroxydeoxyguanosine (8-OH-dG) by attacking C-8 position of deoxyguanosine (dG) in DNA. Effects of oxygen partial pressure or duration of HBO therapy with or without CO poisoning on the tissue 8-OH-dG formation were investigated. Male Sprague-Dawley rats were grouped and exposed to air (control group), 4000 ppm of CO for 10 to 30 minutes (CO only group), air for 30 minutes after 30 minute exposure to 4000 ppm of CO(CO-air exposure group), HBO after 30 minute exposure to 4000 ppm of CO(CO-HBO group), or HBO therapy fo. $10{\sim}120$ minutes(HBO only group). The 8-OH-4G concentrations in the brain and the lung tissues were measured with high performance liquid chromatography and electrochemical detector (ECD). Average concentrations of the 8-OH-dG of each group were statistically compared. In the brain tissues, 8-OH-dG concentrations of the CO only group, the CO-air exposure group, and the CO-HBO group did not significantly differ from those of the control group. Similar insignificance was also found between the CO-HBO group and the HBO only groups. No appreciable dose-response relationship was observed between the 8-OH-dG concentration and the oxygen partial pressure or the duration of HBO. However, the 8-OH-dG concentrations of the 30 minute CO only group were higher than those of the CO-air exposure group (p-value<0.05). In the lung tissues, there were no significant differences between the 8-OH-dG concentrations of the control group and those of the CO only group, the CO-air exposure group, and the CO-HBO group. However, mean 8-OH-dG concentration of the CO-air exposure group was significantly higher than that of the CO only group under the same CO exposure condition(p-value<0.05). With the duration of CO exposure, the 8-OH-dG concentrations of the lung tissues decreased significantly (p-value<0.05). The concentrations of 8-OH-dG in the lung tissues proportionally increased with the duration of HBO, but no such relation was observed with the oxygen partial pressure. These results suggest that the brain may be more resistant to oxygen free radicals as compared with the lungs, and that oxygen toxicity following HBO may be affected by factors other than oxygen free radicals.

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Comparative Evaluation of 25-OH-VitD and 25-OH-VitD3 by Radioimmunoassay (방사면역 측정법에 의한 25-OH-VitD와 25-OH-VitD3의 비교 평가)

  • Lee, Young-ji;Park, Ji-hye;Lim, Soo-yeon;Cheon, Jun-hong;Lee, Sun-ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.24 no.1
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    • pp.33-38
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    • 2020
  • Purpose Vitamin D is essential for maintaining bone health, controling cell proliferation or differentiation, strengthening immune function by controlling calcium metabolism in the body. Vitamin D deficiency can lead to increase the risk of rickets, osteoporosis, cardiovascular disease, diabetes and cancer. Especially, South Korea is one of the highest population proportion of vitamin D deficiency. Accurate determination of levels of 25-OH-VitD or 25-OH-VitD3 in blood serum is required for the diagnosis and treatment of vitamin D deficiency. In this study, radioimmunoassay of 25-OH-VitD and 25-OH-VitD3 was performed and compared to evaluate the effectiveness of Vitamin D radioimmunoassay. Materials and Methods Serum 25-OH-VitD and 25-OH-VitD3 levels were measured using radioimmunoassay. The interrelationship, reproducibility and population distribution rate were evaluated. In addition, the internal quality control was performed at Asan Medical Center from April 2017 to June 2019 and the result of external quality control (Interagency proficiency evaluation) of first and second half of 2018 hosted by the Korean Society of Nuclear Medicine Technology (KSNMT). Both tests were measured by same manufacturer's reagent. Results 25-OH-VitD showed a strong positive correlation on 97 samples, as 25-OH-VitD3 x 0.9 + 0.3 (R>0.9). In repeated measurement, the average Diff(%) value of the reproducibility evaluation of 25-OH-VitD and 25-OH-VitD3 were 7.7% and 7.4%, respectively. Population distribution results showed no statistically significant differences(p>0.05). The resultant value of internal quality control, which measured from April, 2017 to June 2019 in Blood test room of Nuclear Medicine at Asan Medical Center, showed average (CV%) 6.2% and 6.8%, respectively. As a result of the external quality control (interagency proficiency evaluation) Z value obtained under 2.0, as shown below; Conclusion The interrelationship, reproducibility, population distribution rate, internal quality control and external quality control between 25-OH-VitD and 25-OH-VitD3 radioimmunoassay shows superior outcome. Radioimmunoassay, which can be alone measured in the blood as 25-OH-VitD or 25-OH-VitD3, is considered suitable screening tests for the diagnosis of vitamin D deficiency.

A Study on the Silk Dyeing With Natural indigo Extracted from Polygoum tinctorium -On the fermentation dyeing- (쪽 色素에 의한 絹纖維 染色에 관한 硏究 -발효 염색에 대하여-)

  • Jeong, In-Mo;Nam, Seong-U
    • Journal of Sericultural and Entomological Science
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    • v.40 no.1
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    • pp.78-85
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    • 1998
  • Colorants were prepared by extraction of natural indigo which was harvested just in the blooming season(in the late of July). 100 g of fresh leaves soaking in 1 ιwater was kept at 3$0^{\circ}C$, 30 hours. A solution of 3g/l calcium hydroxide was added into it to precipitate dye substance and it was freezing-dried into powder form. The fermentation and dyeing conditions were investigated. The results obtained are summarized as follows; K/S value of dyed silk fabrics of fermentation conditions was higher at 95$^{\circ}C$ for 20 min. than at 4$0^{\circ}C$ for 20 hours. Furthermore, K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value increased as extending of dyeing time when dyed till 2 hours at 3$0^{\circ}C$. K/S value decreased in order of 3$0^{\circ}C$, 4$0^{\circ}C$ and 5$0^{\circ}C$, at the various dyeing temperatures and dyeing concentrations, and colour fastness ranged from 4 to 5 grade in terms of washing, perspiration and light fastness.

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