• Title/Summary/Keyword: Anti-condensation

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Study on the Industrial Process of Rubber Anti-oxidant RD

  • Liu, Yu;Gao, Qinyu;Liu, Lianxin;Shi, Guangxia
    • Journal of the Korean Chemical Society
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    • v.55 no.5
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    • pp.830-834
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    • 2011
  • This paper is on the industrial synthesis process of anti-oxidant RD ((2,2,4-trimethyl-1,2-dihydroquinoline polymer $(C_{12}H_{15}N)_n$. n=2-4)).The content of dimer, trimer and tetramer of RD as the inspection targets, using the orthogonal design method - take the ratios of keto-amine, the reaction time, the reaction temperatures and the ratios of catalyst acid-amine as inspect factors - to optimized the reaction condition. The results indicate that the best ratio of keto-amine is 2:1, the time of salification and condensation is 3 hours and 7.5 hours. The range of temperature of salification and condensation is $135^{\circ}C$ and $120-125^{\circ}C$, and that the best ratio of acid-amine is 0.2: 1 (the proportion is the concentration ratio for mole). Under the optimization conditions, the yield of RD was stabilized and content of RD more than 45%.

Synthesis and Potent Anti-leukemic Activity of Novel 5'-Norcarbocyclic C-nucleoside Phosphonic Acids

  • Kim, Seyeon;Kim, Eunae;Oh, Chang-Hyun;Yoo, Kyung Ho;Hong, Joon Hee
    • Bulletin of the Korean Chemical Society
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    • v.35 no.12
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    • pp.3502-3508
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    • 2014
  • The first synthetic route to 5'-norcarbocyclic C-nucleoside [7-oxa-7,9-dideazadenosine (furo[3,2-d]pyrimidine) and 9-deazaadenosine (pyrrolo[3,2-d]pyrimidine)] phosphonic acids from commercially available 1,3-dihydroxy cyclopentane was described. The key C-C bond formation from sugar to base precursor was performed using Knoevenagel-type condensation from a ketone derivative. Synthesized C-nucleoside phosphonic acids were tested for anti-HIV activity as well as anti-leukemic activity. Compound 26 showed significant anti-leukemic activity.

Localization of Anti-Actin-Gold Particles (10 nm) Labeled to Nuclear Actin of Urechis Sperm and Spermatids (항-액틴-금 입자 표지에 의한 개불(Urechis unicinctus) 정자 및 정세포 핵 Actin의 분포)

  • Shin, Kil-Sang;Kim, Ho-Jin;Kim, Wan-Jong
    • Applied Microscopy
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    • v.30 no.4
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    • pp.403-412
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    • 2000
  • Urechis unicinctus spermatogenic cells, sperm and spermatids, prepared from testis are investigated to identify nuclear actin using amoeba monorlonal anti-actin as the first Ab and gold particles (10 nm) conjugated mouse IgG (immunogold) as the Ab marker. The Ag-Ab reactions analyzed the localization of nuclear actin of the spermatogenic cells and the immunogold particles incorporated mainly with nuclear matrices. A few immunogold particles are merged into the acrosomes and the other architectures of spermatogenic cells, such as mitochondrion and centrioles. It is often observed and there is a tendency in which the incorporated immunogold particles are increased in number in the nuclear matrices of sperm compared with that of spermatids The increments and decrements of the incorporated immunogold particles according to developmental stages and the spermatogenic architec-tures are interpreted and discussed in aspect of acrosomal function and of nuclear condensation of spermatids.

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Fundamental Characteristics of Crack Control for Concrete Used in Fluosilicate Salt Based Anti-crack Agent (규불화염계 균열저감제를 이용한 콘크리트의 균열제어특성)

  • Kang Sung Woong;Yang Il Seung;Han Byung Chan;Kim Do Soo;Kil Bae Soo;Yun Hyun Do
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.289-292
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    • 2004
  • This study was performed to know effective control of crack occurred by hydration heat, restraint of multiplication of hydration heat, through mechanical test, strength test and crack control test using fluosilicate salt based anti-crack agent made from by-product during phosphoric acid manufacturing process. Mix proportions for experiment were modulated at 0.495 of water to cement ratio and addition amount of fluosilicate salt based anti-crack agent to $1.0\%$. Condensation time was late and compressive strength of hardened concrete cured at several days was executed to evaluate characteristics of crack control for concrete. It is ascertained that characteristics of crack control for concrete could be improved by an adequate addition of fluosilicate salt based anti-crack agent.

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Effect of Postharvest High CO2 Treatment and Anti-moisture Pad on the Quality of Fresh Oyster Mushroom during Export Simulation (모의 수출 조건에서 수확 후 CO2와 부직포 패드 처리가 느타리버섯 품질에 미치는 영향)

  • Hwang, Yong-Soo;Lee, Kyeung-Min;Kim, Min-Kyung;Seo, Geon-Sik
    • The Korean Journal of Mycology
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    • v.40 no.4
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    • pp.215-223
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    • 2012
  • This study was aimed to find factors responsible for export potential of oyster mushroom through postharvest treatments including high pressure $CO_2$ and anti-moisture pad. Temperature fluctuation during export simulation induced the condensation of excess moisture resulting in the quality loss due to browning and decay. Anti-moisture pad was effective on inhibition of browning occurrence in part. High temperature exposure ($15^{\circ}C$) as retail simulation greatly offset the positive effect of anti-moisture pad. Short term treatment of high pressure $CO_2$ delayed the surface color changes as hunter L, a, and b values. There was no consistent tendency in total sugar and phenolics between treatments. In general, the export potential of small size mush-room (export size) at harvest was higher than large ones (domestic size). The major factors asso-ciated with the quality decrease of oyster mushroom during export were moisture condensation in packages and temperature fluctuation. Further research is required to improve mushroom export procedures.

Study of Pallet Scale Modified Atmosphere Packaging Films for Reducing Water Condensation

  • Kim, Jinse;Park, Jong Woo;Park, Seokho;Choi, Dong Soo;Choi, Seung Ryul;Kim, Yong Hoon;Lee, Soo Jang;Park, Chun Wan;Lee, Jung- Soo;Cho, Byoung-Kwan
    • Journal of Biosystems Engineering
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    • v.41 no.2
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    • pp.98-107
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    • 2016
  • Purpose: The aim of this study was to find an appropriate polymer film, which could reduce the water condensation for pallet-size modified atmosphere packaging (MAP). Methods: Five different types of films were selected from several commercialized films. Prior to the real food storage test, plastic boxes with wetted plastic balls were used to simulate the high humidity conditions of real food storage. The initial MAP condition was 5% oxygen and 95% nitrogen, and the $O_2$ concentration, the relative humidity and water condensation inside the films were checked on a daily basis. The MAP test for tomatoes was conducted by using the most appropriate film from the five films examined in this study. Results: Every film except Mosspack(R) indicated a similar variation in the $O_2$ concentration over the course of time. The relative humidity near the surfaces of all the films except nylon-6 approached saturation conditions over time. For three kinds of films, namely, low-density polyethylene (LDPE) film, anti-fogging oriented polypropylene (AFOPP) film, and Mosspack(R), the inner surfaces of the films were fully covered with dew after a storage period of a day. Conversely, an area of 4.5% was covered with dew in the case of the poly lactic acid (PLA) film, and there was no dew inside the nylon-6 film. The pallet-size MAP test for tomatoes was conducted by using the nylon-6 film and there was no water condensation inside the nylon-6 film over three weeks of storage. Conclusions: During the pallet scale MAP, water condensation could cause severe fungal infection and wetting of the corrugated box. Hence, it was important to minimize water condensation. This study showed that the MAP films with high WVTR such as nylon-6 and PLA could reduce the water condensation inside the pallet scale MAP.

Synthesis of Novel 2'(β)-Methyl-5'-deoxyapiose Nucleoside Phosphonic Acid Analogues as Antiviral Agents

  • Hong, Joon Hee
    • Journal of Integrative Natural Science
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    • v.8 no.1
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    • pp.48-55
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    • 2015
  • Novel 2'(${\beta}$)-methyl-5'-deoxyapiose purine phosphonic acid analogues were designed and synthesized from 2-propanone-1,3-diacetate. Condensation successfully proceeded from a glycosyl donor 9 under Vorbr${\ddot{u}}$ggen conditions. Condensation of aldehyde 14 with Wittig reagent [(diethoxyphosphinyl)methylidene] triphenylphosphorane gave the desired nucleoside phosphonate analogues 15. Ammonolysis and hydrolysis of phosphonates gave the nucleoside phosphonic acid analogue 17 and 19. The synthesized nucleoside analogues were subjected to antiviral screening against HIV-1. The adenine analogue 19 exhibited weak in vitro activities against HIV-1.

2-Arylethenylchromone Derivatives : Synthesis and Anticancer Activity (2-Arylethenylchronlones유도체의 합성 및 항암활성 검색)

  • 문창상;이경원;이지용;이재열;정봉영;이경태;이용섭
    • YAKHAK HOEJI
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    • v.47 no.6
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    • pp.376-381
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    • 2003
  • 2-Arylchromones, also known as flavones, are among the most ubiquitous classes of natural products occurring in the plant kingdom. On the other hand, 2-styrylchromones are relatively scarce in nature and only a few compounds has been isolated from the blue-green algae species. Therefore, new 2-arylethenylchromone derivatives ( 4a∼n, 5a∼f) were synthesized by the aldol condensation of 2-methylchromone ( 3) with several aromatic aldehydes in order to evaluate their cytotoxicities using a MTT assay on three tumor cells. 2-Arylethenylchromone derivative 4a showed the significant cytotoxic activities on KB, HL-60 and P-388 cell lines with $IC_{50}$/ values of 25.2, 63.59 and 49.51 $\mu$M, respectively, indicating that 2-arylethenylchromone skeleton has a potential anti-tumor application.

Synthesis and Anti-inflammatory Activity of [2-(Benzothiazol-2-ylimino)-4-oxo-3-phenylthiazolidin-5-yl]-acetic Acid Derivatives

  • Sushilkumar S. Bahekar;Devanand B. Shinde
    • Journal of the Korean Chemical Society
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    • v.47 no.3
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    • pp.237-240
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    • 2003
  • A synthetic method for the title compounds (2a-o) was carried out. The title compounds (2a-o)were prepared by the condensation of various thioureas and maleic anhydride. Anti-inflammatory activities in vivo were evaluated and compared with standard drug diclofenac sodium. Some compounds showed moderate activity. The structures of all the new compounds were established on the basis of $^1H$ NMR and IR spectral data.

Anti-proliferating Effects of Some Plants on the Hepatoma Cell (수종 식물들의 Hepatoma cell 증식 저해작용)

  • Chung, Yong Za;Lee, Un Joo
    • Korean Journal of Clinical Pharmacy
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    • v.9 no.2
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    • pp.103-108
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    • 1999
  • The anti-proliferating effects of some plants on hepatoma cell lines were studied by the 3-[4,5-dim-ethylthiazol-2yl]-2,5-diphenyl-tetrazolium bromide (MTT assay), to investigate the anticancer effect with some plants around here. As the result, we saw that the anti-prolferating effect to the plants. Among the plants, Equisetum arvense L. and Lactuca dentata Makino. var, flaviflora Makino of them relatively showed a good ant-proliferating effect. Capsicum annuum L. var. angulosum Mill (Leaf) was the best among them. We also examined morphological changes on the hepatoma cells in this process. In case of Capxicum annuum L. var. angulosum Mill, the tells become vague after 2 days, and then destroyed faster than others. We can fee also the condensated chromosome on the treated cells with Capxicum annuum L. var. angulosum Mill. And we also observed condensation through using a fluorescent microscope by PI staining, and observed DNA fragmentation.

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