• Title/Summary/Keyword: Chemical dosages

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Enzymatic and/or chemical dosages coupled with the clarification of the sample applied to the screening evaluation of heat load in commercial milks

  • Humbert, Gerard
    • 한국유가공학회:학술대회논문집
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    • 2005.10a
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    • pp.11-19
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    • 2005
  • Heat treatment is essential for hygienic safety and for extending shelf-life of milk. Heating of milk affects principally its physicochemical, nutritional and organoleptic properties. The most important changes are the decrease in whey protein solubility and the decrease in stability of casein micelles. Maillard reactions are also important and undesirable consequences.

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Changes in Bioactive Compounds Contents of 'Maehyang' and 'Seolhyang' Strawberry Fruits by UV Light Illumination

  • Kim, Sung-Kyeom;Bae, Ro-Na;Chun, Chang-Hoo
    • Horticultural Science & Technology
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    • v.29 no.3
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    • pp.172-180
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    • 2011
  • The net photosynthetic rate of 'Seolhyang' strawberry plants was measured daily for 7 days after treatment at three UV illumination dosages (0, 9.8, and 29.5 $kJ{\cdot}m^{-2}$). The net photosynthetic rates of the strawberry plants with 9.8 and 29.5 $kJ{\cdot}m^{-2}$ UV light illumination decreased by 20.2 and 61.4%, respectively, at 7 days after UV light treatments. UV treatments with two illumination dosages (7.9 and 15.7 $kJ{\cdot}m^{-2}$) altered the phenolic compounds contents during the cultivation period when compared to those in the control fruits. The anthocyanin content with 7.9 $kJ{\cdot}m^{-2}$ UV light illumination of 'Seolhyang' increased by 18.7% compared with those in control fruits at the 11 DAT. However, the anthocyanin content of 'Maehyang' was not significantly different among treatments during experiment period. The highest level of ellagic acid was found with 7.9 $kJ{\cdot}m^{-2}$ UV light illumination in both cultivars at the 11 DAT. Our results showed that strawberries illuminated with UV light during cultivation period had higher bioactive compounds contents than control fruits. These results suggest that UV light treatments may be a useful non-chemical way of promoting strawberry fruits quality.

Effect of Media in Advanced Treatment of Sewage Using Submerged Membrane-Coupled Sequencing Batch Reactor (침지형 막결합 연속회분식 반응기를 사용한 하수의 고도처리에서 담체의 효과)

  • Kim, Seung-Geon;Lee, Ho-Won
    • Membrane Journal
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    • v.26 no.6
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    • pp.470-479
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    • 2016
  • In the advanced treatment of sewage using the submerged membrane-coupled sequencing batch reactor (SMSBR) with media, the effect of media on the filtration performance and removal efficiency were investigated. Dosages of the media in the SMSBR were 10% based on working volume of reactor. As a control system, SMSBR without media and PAC, SMSBR with PAC (10 g/L) only, and SMSBR with media and PAC were also operated. The experimental results showed that there was no big difference observed in the removal efficiencies of COD, T-N, and T-P irrespective of the dosages of the media and PAC. But transmembrane pressure (TMP) of SMSBR with media increased slowly during the operation time, while that of SMSBR without media increased rapidly. Using SMSBR with media, it was possible to operate without the membrane cleaning during the 91 days. Using SMSBR with media only, after 80 days the average removal efficiencies of COD, T-N, and T-P were 95.0, 69.3%, and 51.4%, respectively.

The Effect of Media on the Removal Efficiency and Filtration Performance in the Submerged Membrane-Coupled Sequencing Batch Reactor with Media (담체가 첨가된 침지형 막결합 연속회분식 반응기에서 제거효율과 여과성능에 대한 담체의 효과)

  • Kim, Seung-Geon;Lee, Ho-Won
    • Membrane Journal
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    • v.22 no.6
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    • pp.450-460
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    • 2012
  • In the submerged membrane-coupled sequencing batch reactor (MSBR) with sponge type media, the effect of media on the removal efficiency and filtration performance were investigated. Dosages of the media in the MSBR were set of 5%, 10%, and 20% based on working volume of reactor. As a control system, the MSBR without media was also operated. The experimental results showed that there was also no difference observed in the removal efficiencies of COD, T-N, and T-P irrespective of the dosages of the media. But TMP (transmembrane pressure) of the MSBR with media increased slowly during the operation time, while that of the MSBR without media increased rapidly at the initial operation. This result was thought that the collisions between flat membrane and moving media gave shear forces which decreased the cake layer on the surface of flat type membrane. Consequently, this study showed that filtration performance of the MSBR with media was greatly enhanced compared with that of the MSBR without media. The MSBR with media suggested in this study can be a good candidate for the wastewater treatment.

Preparation of Alginate/Poly(N-isopropylacrylamide) Hydrogels Using Gamma-ray Irradiation Grafting

  • Lee, Young-Moo;Lee, Sang-Bong;Seo, Sung-Mi;Lim, Youn-Mook;Cho, Seong-Kwan;Nho, Young-Chang
    • Macromolecular Research
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    • v.12 no.3
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    • pp.269-275
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    • 2004
  • To graft N-isopropylacrylamide (NIPAAm) onto alginate, varying dosages of ${\gamma}$-rays were irradiated onto alginate films in deionized water and methanol media, which are non-solvents of alginate. We investigated the hydrogels graft ratio, mechanical strength, swelling kinetics and ratio, and behavior with respect to drug release. The graft yield of NIPAAm increased upon increasing the irradiation dose. The use of the aqueous solution increased the graft yield relative to that obtained in methanol. The mechanical strength of the grafted hydrogels increased after grafting with NIPAAm. In a study of the swelling kinetics, we found that all hydrogels reached an equilibrium swollen state within 3 h. The equilibrium swelling ratio of the hydrogels decreased upon increasing the irradiation dose. The swelling ratio of the hydrogels decreased dramatically between 30 and 35$^{\circ}C$ because phase separation of NIPAAm occurred at 32$^{\circ}C$. The swelling process, with respect to the temperature change, was repeatable. An NIPAAm-grafted alginate containing a drug sustained its release rate until 3 h after an initial high drug release caused by a burst effect.

Decolorization of Dyeing Wastewater with Use of Chitosan Materials

  • Xin, Chen;Sun, Hui-Li;Pan, Jia-Hui
    • Ocean Science Journal
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    • v.41 no.4
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    • pp.221-226
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    • 2006
  • More attention has been paid to the research on decolorization of dyeing wastewater nowadays. In this study, an investigation into the decolorization of dyeing wastewater was conducted using a combination of coagulant, carboxymethyl chitosan (NOCC) and coagulant aid, polyscrylamide (PAM). The factors influencing the decolorization efficiency, such as pH value, coagulant and the dosages of coagulant, were discussed. The results showed that using PAM as coagulant aid could reach a high decolorization efficiency compared with using NOCC alone. The optimal conditions were pH 2.3, 480 mg/L for NOCC, and 4-8 mg/L for PAM. Under the optimum conditions, the rate of decolorization could achieve 99%, and the removal of chemical oxygen demand (COD) could achieve 90%. In addition, the membrane processes with chitosan/rare-earth-metals could enhance the decolorization rate of Direct Black FF to 94.7%, and Indanthren Red F3B to 98.2%, respectively.

A Study on the Treatment of Wastewater Containing Surfactants (계면활성제를 함유한 폐수의 효율적 처리 방법에 관한 연구)

  • Shin, Myoung-Ok;Chung, Moonho
    • Journal of Environmental Health Sciences
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    • v.23 no.3
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    • pp.109-120
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    • 1997
  • The purpose of this study is to evaluate the effectiveness of wastewater treatment containing surfactant. For that, comparative analysis of effectiveness of Featon Oxidation, Aluminum Sulfate, PAC (Poly Aluminum Chloride) on the treatment of the synthetic wastewater containing LAS (Linear Alkyl Sulfate), a main component of the commercial detergent was carried. Then, the optimum pH, the dosage of reagents, and the concentration of the LAS in each treatment were determined. The results of the study were summarized as following. 1. In Fenton Oxidation, optimal pH was 3 and 97.92% removal of LAS was achieved. However, the increase of the pH reduced the efficiency of LAS removal. The proper chemical dosages of FeSO$_4$ and $H_2O_2$ were 300 mg/l and the increase of dosages didn't affected the removal efficiency. Therefore, it was concluded that the economic chemical dosage was 300 mg/l of FeSO$_4$ and $H_2O_2$. 2. In case of Alum treatment, optimal pH was 11 with 61.13% removal efficiency. At other pH range, the removal efficiency was very low indicating that removal efficiency is greatly influenced by pH. The proper chemical dosage was 200 mg/l with the removal efficiency of 77.65%. The increase of chemical dosage, however, reduced the removal efficiency. 3. In case of using PAC, optimal pH was 6 with 97.99% removal efficiency. The result showed that wastewaters containing surfactant were almost completely removed at pH 6 by PAC. Removal efficiency was decreased by increasing PAC dosage higher than 400 mg/l and dosage over 700 mg/l of PAC abolished the treatment. 4. The comparative analysis of three methods revealed that the effective pH ranges were at pH 2-5 with Fenton oxidation, at pH 6-11 with PAC, and pH 11 with Alum. The removal efficiencies at these pH were 83.95-97.92%, 75.98-97.99% and 61.13%, respectively. 5. Increase in LAS concentration reduced the removal efficiencies of all three methods. In the case of PAC or Alum treatment, treatment abolished at LAS concentration higher than 700 mg/l.

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Chemical Immobilization of Reticulated Giraffe (Giraffa camelopardalis reticulata) Using Medetomidine and Ketamine (Medetomidine과 Ketamine을 사용한 그물무늬 기린마취에 대한 고찰)

  • Kim, Kyoo-tae;Kim, Jong-bu;Chang, Kyung-cheol;Lee, Il-bum
    • Korean Journal of Veterinary Research
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    • v.43 no.3
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    • pp.501-505
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    • 2003
  • The chemical immobilization in giraffes (Giraffa camelopardalis reticulata) remains a challenge because of their size, behavior, and anatomic and physiologic characteristics that commonly create life threatening problems during immobilization. The drug combination medetomidine (MED) and ketamine (KET) was administered by remote injection. The dosages of MED and KET were correlated to the giraffe's shoulder height (SH), become recumbent with a dosage of $114{\mu}g$ of MED and 2.1 mg of KET, $320{\mu}g$ of atipamezole per cm of SH, respectively. After injection of the drugs, initial signs of sedation including ataxia were noticed at 3 minutes followed by lateral recombency at 12 minutes. The mean heart rate, respiratory rate and rectal temperature recorded during the procedures were 55 beats per minute, 48 breaths per minute and $36.6^{\circ}C$, respectively. Atipamezole was administered, after 33 minutes result in death. Assuming that 24 hours fasting times were short and light esteemed of atipamzole adverse effects like vomiting, passive regurgitation.

Colour Removal from Aqueous Solutions by Flotation Process (부상공정에 의한 수용액으로부터 색 제거)

  • Roh, Sung-Hee;Yun, Young-Jae;Kim, Jin-Hwan;Kim, Sun-Il
    • Applied Chemistry for Engineering
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    • v.10 no.4
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    • pp.576-580
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    • 1999
  • The removal of colours from aqueous solution and/or dispersions has been studied by dispersed-air flotation, in a semi-batch column. Two colours were used for the experiments: Basic Yellow 28(basic) and Direct Orange 31(basic). All two effectively removed by flotation within 8 min. Sodium dodecyl sulfate, sodium oleate and amines were found to be effective as collectors in the removal of colour, which was found to be related to the pH of the solution and the amount of collector added to it, with high collector dosages causing the process to become pH-independent.

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