• 제목/요약/키워드: $SC-CO_2$ extraction

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Prediction of Phase Behavior of ε-caprolactam Derivatives and Carbon Dioxide using a Group Contribution Method (그룹 기여 방법을 이용한 ε-caprolactam 유도체와 이산화탄소의 상거동 예측에 관한 연구)

  • Kwon, Soyoung;Bae, Won;Lee, Kyoungwon;Kim, Hwayong
    • Clean Technology
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    • v.11 no.3
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    • pp.117-122
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    • 2005
  • N-vinyl caprolactam (NVCL), a kind of N-vinyl amide monomer, must be dissolved in continuous phase ($scCO_2$) for dispersion polymerization in supercritical carbon dioxide. Phase behavior of $CO_2$+NVCL is very important and necessary for determining initial polymerization condition and for monomer extraction from final polymer. There is the limitation of experimental method for obtaining pure properties of the monomer because of the possibility of polymerization. And N-methyl caprolactam (NMCL) is the useful solvent for the gas treating process. In the viewpoint of molecular thermodynamics, NVCL and NMCL have same functional group i.e. ${\varepsilon}$-caprolactam. In the case of NVCL, hydrogen of amide group is substituted with vinyl group and for NMCL, hydrogen of amide group is substituted with methyl group. We suggested modified group contribution method for this ${\varepsilon}$-caprolactam derivatives. This new group contribution parameter was applied to correlate $CO_2$ + N-vinyl caprolactam or N-methyl caprolactam system.

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Geochemical Characteristics and Trace Metal Speciation of Soils in Major Source Area of Asian Dust (주요 황사발원지 토양의 지구화학적 특성 및 미량원소 존재형태 연구)

  • Lee, Pyeong-Koo;Youm, Seung-Jun;An, Gi-O
    • Economic and Environmental Geology
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    • v.45 no.1
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    • pp.9-21
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    • 2012
  • In this study, we investigated the chemical characteristics of soils collected from the several deserts and loess in China known as the typical source areas of Asian dust (the Taklamakan desert, the Alashan desert, the Ordos desert and the Loess Plateau). Based on our analysis, we examined the possibility of adverse effects on environments and human health. In each desert and loess, major elemental compositions of soils did not show large variations, implying that the long-periodic mixing of soils in each area made their chemical compositions homogeneous. Minor elements of soils in each desert and loess showed more complicated patterns with strong correlations each other (e.g., Cr, Cu, As, Co, Ni, V, Y, Sc, Sn, Pb, Zn, Cd, Cs, Li, Th, U). These results thus enable us to discriminate the soil of the Loess Plateau from those of the other deserts in China. The results of sequential extraction experiments for soils showed that the chemical speciation of Fe was dominant in residual fraction (>85%) in all deserts and loess, but the fractions of Mn and Ca chemical speciations were very different in each area. In the case of Mn, the fraction of amorphous Fe-Mn hydroxides (55.4%) in the Central Loess Plateau and the carbonate fraction (33.8%) in Taklamakan desert were higher as much as 2 to 5 times than other deserts. The chemical speciations of Ca are dominant in carbonate fraction in Taklamakan (75.9%) and Alashan (50.5%) deserts, but carbonate fractions of Ca in the Loess Plateau and Ordos deserts were low (6.6% and 2.1%, respectively). According to the mobility of trace elements inferred from the results of sequential extraction procedure, we could classify them into five groups, and the mobility of Cd, Pb and Cu are more than 87%, 33% and 30%, respectively. Therefore, Cd, Pb and Cu in soils of deserts and loess could be easily dissolved when interacted with surface water. As such, they could give adverse effects on surficial environments and human health.

A Study on Anti-oxidant and Anti-wrinkle Effect of Supercritical Fluid Extraction of Black Carrot as a Functional Cosmetic Material (기능성화장품소재로서 자색당근 초임계추출물의 항산화 및 항주름 효능 연구)

  • Kim, Ji-Su;Lee, Ji-An
    • Journal of Convergence for Information Technology
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    • v.11 no.12
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    • pp.236-243
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    • 2021
  • The aim of this study was to evaluate the anti-oxidant and anti-wrinkle effect of the black carrot(BC) extracted by supercritical dioxide(SC-CO2). DPPH/ABTS radical scavenging and total polyphenol contents were measured to investigate the anti-oxidant activity of the BC supercritical extract. Collagen production and MMP-1 expression were assessed in normal human dermal fibroblasts(NHDF) for anti-wrinkle activity, The black carrot extract showed the highest total phenolic content(9.037±1.123 mg GAE/g extract) and the best antioxidant properties as shown by DPPH and ABTS assay. The supercritical fluid extracts of black carrot exhibited low toxicity to NHDF cells. In addition, the supercritical fluid extracts showed MMP-1 inhibition and type I pro-collagen synthesis inducing activities in a dose-dependent manner, respectively. Therefore, these results suggest that the black carrot is a potential source of high anti-oxidative, solvent-free and anti-aging material with promising applications in cosmetic, food, and beauty-food industries.

Biological Activities of Polysaccharide Extracted from the Fruit Body and Cultured Mycelia of Phellinus linteus IY001 (목질진흙버섯 자실체와 배양 균사체 유래 ${\beta}-Glucan$성 다당류의 생리활성)

  • Lee, June-Woo;Baek, Sung-Jin;Bang, Kwang-Woong;Kang, Shin-Wook;Kang, Sang-Mo;Kim, Byung-Yong;Ha, Ick-Su
    • Korean Journal of Food Science and Technology
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    • v.32 no.3
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    • pp.726-735
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    • 2000
  • This study was conducted to investigate the biological activities of polysaccharide extracted from the fruit body and cultured mycelia of Phellinus linteus IY001. All fractions were extracted by hot water, in the next, Fr. I, Fr. II, Fr. III and Fr. IV were polysaccharide obtained by ethanol precipitation or ultrafiltration. The highest antitumor activity against sarcoma 180 in ICR mice was observed in Fr. III and Fr. IV at the level 85%, but the antitumor activity had no connection with their anticomplementary activity in vitro, it might probably be due to extraction of hot water. All fractions promoted the production of nitric oxide and $TNF-{\alpha}$ in macrophage, addition of Fr. I and Fr. II resulted in production of nitric oxide$3(5.9{\sim}37.6\;{\mu}M)$ and of the $TNF-{\alpha}$ production($8,696.2{\sim}9,420pg/ml)$. All fractions inhibited the lipid peroxidation induced by $AsA/Fe^{2+}$, $ADP/NADPH/Fe^{3+}\;and\;CCl_4/NADPH$ in rat liver microsomes, and Fr. III showed the electron donating ability stronger than tocopherol in assay system using DPPH. From these results, it is suggested that all fractions contain immunoregulatory components which may protect cellular materials from the oxidative damages by their radical scavenging activities.

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Development of a Personal Compound Stimulus Device for Skin-care (개인용 피부미용 복합자극기 개발)

  • Lee, Jeon;Kim, Chi-Hyun;Chung, Geum-Hee
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.1
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    • pp.12-19
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    • 2012
  • Recently, the market of skin-care device has been steadily growing up. In this paper, we tried to develop a personal compound stimulus device more competitive than existing products. As the compound stimulus, biochemical stimulus of herbal extraction fluid, thermal stimulus of plate-shaped carbon fiber heater, and optical stimulus of near infrared LED were selected. By some evaluation tests, the thermal stimulation part and the optical stimulation part were found to be developed properly. Additionally, the efficacy of the mixed stimulus of thermal and optical stimulation was tested in C2C12 mouse myoblast. Through RT-PCR analysis, it was found that, by the developed compound stimulus, the expression of collagen I mRNA and collagen III mRNA increased by 4.9 and 1.3 times respectively.