• 제목/요약/키워드: Preparation Method

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Preparation of Ag Powder from AgNO3 by Wet Chemical Reduction Method1. The Establishment of Optimum Reaction System for the Preparation of Spherical Ag Powder (습식 화학적 환원법에 의한 AgNO3로부터 Ag 분말의 제조 1. 균일한 구형 Ag 분말의 제조를 위한 최적 반응계 확립)

  • Yuna, Ki-Seok;Park, Young-Chul;Yang, Beom-Seok;MIn, Hyun-Hong;Won, Chang-Whan
    • Journal of Powder Materials
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    • v.12 no.1
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    • pp.56-63
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    • 2005
  • Ag powder was prepared from $AgNO_3$ by wet chemical reduction method using various reduction agent system involving $AgNO_3$, $AgNO_2$(AgCl) and Ag complex ion aqueous solution. The pure Ag powder could be prepared regardless of reaction system but the particle shape and distribution were affected very much according to the kind of reduction agents and reaction systems. The optimum reaction system for the preparation of the silver powder having the uniform particle shape and size distribution was Ag complex ion aqueous solution-reduction agent system and in particular, $H_2O_2$ and $C_6H_8O_6$as a reduction agent leaded the more uniform particle shape and size distribution.

Changes in Pectic Substances of Korean Pickled Cucumbers with Different Preparation Methods (담금 방법을 달리한 오이지의 숙성 중 펙틴질의 변화)

  • 장명숙;박미원;박용곤
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.1
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    • pp.133-140
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    • 1995
  • This investigation was undertaken for the purpose of studying the changes of pectic substances in alcohol insoluble solids(AIS) extracted from cucumbers pickled in salt. The preparation methods were brining the cucumbers in 10% NaCl solution (bolied, method A), 20% NaCl solution(bolied, method B) and 20% NaCl solution(cool to $25^{\circ}C$ after boiling, method C). The composition ratio of hot water soluble pectin(HWSP) in AIS decreased during brining, while that of 0.4% sodium hexametaphosphate soluble pectin(NaSP) increased remarkably. The contents of Ca and Mg in AIS increased regardless of preparation methods used. By DEAE-cellulose chromatography, HWSP from fresh and brined cucumbers were divided into six fracitons. 0.2M peak was the main fraction in fresh cucumber, whereas 0.05M and 0.2M peak were the main fraction in pickled cucumbers. On the other hands, NaSP from fresh and brined cucumbers were divided into five fractions and 0.4M peak was the main fraction. However, the composition ratios of galacturonic acid and neutral sugar of 0.4M fraction in brined cucumbers were higher than those of fresh cucumber.

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Determination of Recombinant Human Epidermal Growth factor (rhEGF) in a Pharmaceutical Preparation by Capillary Electrophoresis

  • Hwang, Kyung-Hwa;Lee, Kang-Woo;Kim, Chang-Soo;Han, Kun;Chung, Youn-Bok;Moon, Dong-Cheul
    • Archives of Pharmacal Research
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    • v.24 no.6
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    • pp.601-606
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    • 2001
  • A simple assay method of recombinant human epidermal growth factor (rhEGF) in a pharmaceutical preparation was studied and validated by capillary electrophoresis (CE) using micellar electrokinetic chromatography (MEKC) techniques. Factors affecting the migration behavior and separation performances of the peptide; type of buffers pH, butler concentration, and concentration of sodium dodecyl sulfates (SDS) were investigated to optimize the analytical performance. CE was performed using running buffers 50.0 mM borate (pH 8.5) containing 12.5 mM SDS at 20 $mutextrm{V}$ of the applied voltage. Calibration curves for the rhEGF showed good linearity (r>0.999) over the wide dynamic range from 1.25 to $100{\mu\textrm{g}}/ml$. Sample analysis was performed by using standard addition method to eliminate the matrix effects of dosage vehicle. This method is assumed to be useful for quality control (QC) of various forms of pharmaceutical products of the peptide.

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Quality Characteristics of Squid Sikhae by Preparation Method and Fermentation Conditions (오징어 식해의 제조 방법에 따른 품질 특성)

  • Lee Ye-Kyung;Park Bum-Do;Kim Soon-Dong
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.4
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    • pp.405-412
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    • 2005
  • Quality characteristics of squid-sikhae prepared by four different methods(SHM: sikhae method, SHM-LA; sikhae method added with L plantarum, MM; mixed method of sikhae method and salting method, MM-LA; MM method added with L plantarum) were investigated during fermentation at $20^{\circ}C$. The pHs of all the 6-days fermented sikhae samples were in the range of 4.01-3.76, meaning that there were no significant difference in pH according to the preparation methods. Number of total microbes(TM) were decreased, while the ratio of lactic acid bacteria against TM in SHM-LA and MM-LA was higher than those of SHM and MM. There were no differences in acid protease activity, while $NH_2-N$ content of SHM and MM were higher than those of SHM-LA and MM-LA. Amylase activity was the lowest in MM-LA. Proteins separated by SDS-PAGE belonged to 7-200 kDa, the major proteins (153<94<41 kDa) of the sikhae in all plots were disappeared at 6 days fermentation. In sensory evaluation, sour taste of MM was the highest, while it was the lowest in SHM-LA. Sweet taste, bitter taste, salty taste and hot taste were not significantly different Off-flavor was decreased in lactic acid bacteria added products. Scores of the softness and overall acceptability were the highest in SHM-LA. These results indicated that SHM-LA was the best method for the preparation of squid sikhae because of the enhancement of lactic acid fermentation and overall acceptability.

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A Survey on the Management Status of Extramural Herbal Dispensaries (원외탕전실 관리현황 설문조사 연구)

  • Ahn, Ung-chan;Kim, Hyeon-Dong;Kim, Ji-Hoon;Rho, Tae-Won;Han, Sang-Yong;Kim, Yun-Kyung
    • Herbal Formula Science
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    • v.24 no.1
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    • pp.1-16
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    • 2016
  • Objectives This study was conducted to investigate the management status of extramural herbal dispensary facility, which could serve as a foundation for further research and policy establishment.Method According to herbal dispensary data collected by Ministry of Health and Welfare, 78 sites were confirmed among 1,160 sites which checked extramural herbal dispensary facility. We carried out a survey on them. The survey consisted of 42 questions including general provisions, personnel management, spaces and facilities, equipment and utensils, procedure requirement for production and/or processing.Results From their responses, hygiene was regarded generally admittable. In personnel management, some answers that herbal medicines were prepared not by Korean medicine doctor or pharmacist, but by general worker. On preparation method, dosage frequency and volume were different among preparation facilities. Regarding facility management, prescription inspection was substantially carried out in many extramural preparation facilities, however, some of them was not.Conclusion There was a need for regulation of detailed management including facility, preparation, personnel management, etc., of extramural preparation facility. Furthermore, There was also a need for standardization of procedure on decoction, water management, medicinal herbs management, etc.

Suggestion of Model Change Work Improvement by REBA and Therblig

  • Lee, Sung-Koon;Park, Peom
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.6
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    • pp.757-764
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    • 2011
  • Objective: The aim of this study was to provide a method to improve the compliance and reduce the time by reducing the workload during the model change work. Background: The enterprises are constructing the small quantity batch production system by increasing the number of model change and reducing model-changing. However, the compliance is low because the work is strenuous and high skills are needed, so the system management is facing with many difficulties. Method: After classifying the model change work according to the purposes(preparation, change and adjustment) with the target of mascara filling machine, element tasks time were measured and the motion analysis(therblig symbol) and REBA analysis were performed. The study incorporated 3 independent variables as the number of motion, REBA score and the element time. The dependent variable is the type of element work as preparation, change and adjustment. The statistical test was performed by one-way ANOVA(${\alpha}$ < 0.05). Results: For the preparation, the number of motions appeared in the order of Use(U), Transport Loaded(TL), and Position(P). The order appeared in change is Use(U), Release Load(RL), and Grasp (G). The adjustment appeared in the order of Position(P) and Use(U). The results of average motion time as the element work times divided by the number of motion appeared in the order of adjustment(1.85sec/motion), preparation(1.11sec/motion), and change(0.62sec/motion). The results of REBA showed that the average risk level of change and adjustment were medium, but 53.1% of change and 42.9% of adjustment were evaluated as high. Conclusion: Reducing the avoidance and improving the compliance of work could be expected if the job autonomy were improved by improving the working postures with high risk level. Application: It is expected to solve the problem of reducing the time of model change work in the small quantity batch production system. The future work is to carry out the improvement directions found in the results and compare the results after improvement.

Fabrication and Application of Micro Polymer Chip Platform for Rare Cell Sample Preparation (희귀 세포 샘플 준비를 위한 마이크로 폴리머 칩 플랫폼 제작 및 활용)

  • Park, Taehyun
    • Journal of the Korea Convergence Society
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    • v.9 no.3
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    • pp.217-222
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    • 2018
  • In this paper, a new micro polymer chip platform and protocol were developed for rare cell sample preparation. The proposed platform and protocol overcome the current limitation of the dilution method which is based on statistics and the FACS method which expensive and requires fluorescence staining. It allows collecting exact number of target cells simply and selectively because the cells are visually confirmed during the collecting process. The collected cells can be transported or spiked into a desired locations, such as a microchamber, without cell loss. This research may applicable not only to a rare cell sample preparation for Lab on a Chip cancer diagnosis, but also to a single/double/multiple cell sample preparation for a cell analysis field. To verify this platform and protocol, five human breast cancer cells (MCF-7) were collected and transported into a hemocytometer chamber.

Correlation between the Content and Pharmacokinetics of Ginsenosides from Four Different Preparation of Panax Ginseng C.A. Meyer in Rats

  • Jeon, Ji-Hyeon;Lee, Jaehyeok;Lee, Chul Haeng;Choi, Min-Koo;Song, Im-Sook
    • Mass Spectrometry Letters
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    • v.12 no.1
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    • pp.16-20
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    • 2021
  • We aimed to compare the content of ginsenosides and the pharmacokinetics after the oral administration of four different ginseng products at a dose of 1 g/kg in rats. The four different ginseng products were fresh ginseng extract, red ginseng extract, white ginseng extract, and saponin enriched white ginseng extract prepared from the radix of Panax ginseng C.A. Meyer. The ginsenoside concentrations in the ginseng product and the rat plasma samples were determined using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Eight or nine ginsenosides of the 15 tested ginsenosides were detected; however, the content and total ginsenosides varied depending on the preparation method. Moreover, the content of triglycosylated ginsenosides was higher than that of diglycosylated ginsenosides, and deglycosylated ginsenosides were not present in any preparation. After the single oral administrations of four different ginseng products in rats, only four ginsenosides, such as 20(S)-ginsenosides Rb1 (GRb1), GRb2, GRc, and GRd, were detected in the rat plasma samples among the 15 ginsenosides tested. The plasma concentrations of GRb1, GRb2, GRc, and GRd were different depends on the preparation method but pharmacokinetic features of the four ginseng products were similar. In conclusion, a good correlation between the area under the concentration curve and the content of GRb1, GRb2, and GRc, but not GRd, in the ginseng products was identified and it might be the result of their higher content and intestinal biotransformation of the ginseng product.

Shape-Stabilized Phase Change Materals : Frozen Gel from Polypropylene and n-Octadecane For Latent Heat Storage

  • Son, Tae-Won;Kim, Tae-Hun;Kim, Bong-Shik;Kim, Byung-Giu
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.375-375
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    • 2006
  • The preparation methods are to be used as "melting method" and "absorption method", respectively. The reaction mixture in the reaction container was heating up the reaction mixture to $200^{\circ}C$ for 2 hour. The mixing time of lab scale preparation should be provided quit long, instead of the short working time in a compounder vessel. And The PP-PCM mixture in the reaction container was heating up the mixture around $60-80^{\circ}C$ for 2 hour. A melting method of frozen gel with 50/50 weight ratio of polypropylene-normal octadecane was prepared by adding PP chip and normal octadecane. An absorption method of frozen gel with 70/30 weight ratio of PP 4.8-normal n-octadecane was prepared by adding PP powder and normal octadecnae.

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Effects of pH on Preparation of Au-Coated $TiO_2$ Nanoparticles by Deposition-Precipitation Method

  • Nguyen, Dung The;Kim, Dong-Joo;Kim, Kyo-Seon
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.150-150
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    • 2009
  • We prepared the Au-coated $TiO_2$ (Au/$TiO_2$) nanoparticles by deposition-precipitation (DP) method with and without bases (urea or NaOH) and investigated the effects of pH on the preparation of Au/$TiO_2$ nanoparticles for various kinds of bases. For the DP method without bases, the Au nanoparticles in the diameter of about 50 nm were generated in the solution by the reduction reaction with trisodium citrate and they did not deposit on the surface of $TiO_2$. For the DP method with bases, Au precursors deposited on the surface of $TiO_2$ and then reduced to the Au nanoparticles in the diameter of 4-5 nm on the surface of $TiO_2$ by the reaction with trisodium citrate.

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