• Title/Summary/Keyword: Chemical structure

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Preparation and Anti-fouling Properties of PVDF Mixed Matrix Asymmetric Membranes Impregnated with 𝛽-cyclodextrin (𝛽-사이클로덱스트린을 함침시킨 PVDF 혼합기질 비대칭막의 제조와 내오염성 평가)

  • Shin, Sung Ju;Lee, Jong Sung;Lee, Jeong Gil;Youm, Kyung Ho
    • Membrane Journal
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    • v.31 no.6
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    • pp.434-442
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    • 2021
  • Poly(vinylidene fluoride) (PVDF) membrane has a good membrane durability because of its high mechanical resistance, thermal and chemical stability. However, the strong hydrophobic property of PVDF membrane can induce a low water permeability and easy fouling by proteins and organic matters. In order to improve the anti-fouling properties of PVDF membrane, the PVDF mixed matrix asymmetric membranes impregnated with biofunctional material 𝛽-cyclodextrin (𝛽-CD) in the membrane structure were prepared by phase inversion method. The membrane filtration experiments of pure water and BSA solution were performed using the PVDF/𝛽-CD mixed matrix asymmetric membranes prepared according to the 𝛽-CD contents. The experiments showed that the introduction of 𝛽-CD into the PVDF polymer matrix contributed to increase in the hydrophilic property of the PVDF membranes, and this led to the reduction of contact angles and improvement of anti-fouling properties. The PVDF/𝛽-CD membrane which was prepared using the dope solution with a 2 wt% 𝛽-CD content represented 64 L/m2·h of pure water flux, 95% of BSA rejection and maximum 80% of flux enhancements compared to flux results of the pristine PVDF membrane.

Experimental Study for Evaluating Early Age Shrinkage of Mortar for 3D Printing (3D 프린팅용 모르타르의 초기재령 수축거동 평가를 위한 실험적 연구)

  • Seo, Eun-A;Yang, Keun-Hyeok;Lee, Ho-Jae
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.26 no.2
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    • pp.76-83
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    • 2022
  • Since the 3D printing mortar is exposed to the atmosphere immediately after printing, moisture is largely evaporated from the surface of the layer. The evaporation of moisture on the surface of the layer greatly causes drying shrinkage and increases the risk of cracking and damage to the structure due to drying shrinkage. This study experimentally evaluated the shrinkage behavior of the initial age using the mortar used for 3D printing. The change in shrinkage was evaluated by comparing the shrinkage of the specimen cured by the sealing method and the atmospheric exposure method. In addition, compared with the case where type 1 cement was used 100%, the shrinkage amount was evaluated when 20% of fly ash was replaced and 10% of silica fume was used. In particular, the effect of three chemical admixtures applied using 3D printing on shrinkage was evaluated experimentally. When fly ash and silica fume were used, the shrinkage amount increased by 60 - 110% compared to the case when type 1 cement was used. The application of viscosity modifiers and shrinkage reducers reduced the shrinkage by at least 18% and at most 70% depending on the curing conditions. The temperature of the specimen temporarily decreased to 15 ℃ at the beginning of curing, and the correlation between the internal temperature of the specimen and the shrinkage behavior was observed.

Whitening and Anti-oxidative Constituents from the Extracts of Hydrangea petiolaris Leaves (등수국 잎 추출물 유래 미백 및 항산화 활성 성분)

  • Jo, Seong Mi;Kim, Jung Eun;Lee, Nam Ho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.48 no.2
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    • pp.123-134
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    • 2022
  • In this study, the whitening and antioxidant effects of the extracts from Hydrangea petiolaris (H. petiolaris) leaves was confirmed, and the chemical structure was identified by separating the active ingredients. In the whitening tests using α-MSH stimulated B16F10 melanoma cells, the n-hexane (Hex) fraction inhibited the cellular melanogenesis and intracellular tyrosinase activities without causing cell toxicity. In addition, the Hex fraction reduced expression of tyrosinase and TRP-2 protein. Upon the anti-oxidative studies by DPPH and ABTS+ radicals, potent radical scavenging activities were observed in the ethyl acetate (EtOAc) fraction. Also, for the cellular protective effects on HaCat keratinocytes damaged by H2O2, the EtOAc fraction indicated protective effects against oxidative stress. Eight phytochemicals were isolated from the extract of H. petiolaris leaves; ethyl linoleate (1), ethyl linolenate (2), 1-linoleoyl glycerol (3), 1-linolenoyl glycerol (4), epi-catechin (5), afzelin (6), quercitrin (7), hyperin (8). Among the isolates, the compounds 5 - 8 showed DPPH and ABTS+ radical scavenging activities. The contents of quercitirin, a major isolated in this extract, determined by HPLC analysis were confirmed to be about 31.3 mg/g for the 70% ethanol extract and 169.8 mg/g for the EtOAc fraction. Based on these results, it was suggested that the extract from H. petiolaris leaves could be potentially applicable as whitening and anti-oxidative ingredients in cosmetic formulations.

Development of Transparent Cleansing Water with Salicylic Acid and Capryloyl Salicylic Acid (살리실릭애씨드 및 카프릴로일살리실릭애씨드가 적용된 투명 클렌징 워터의 개발)

  • Yeo, Hye Lim;Park, Injeong;Jung, So Young;Lee, So Min;Kim, Hyung mook;Lee, Mi-Gi;Kwak, Byeong-Mun;Bin, Bum-Ho
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.48 no.2
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    • pp.87-95
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    • 2022
  • This study is about the development of transparent cleansing water with one of the beta-hydroxy acids (BHA), salicylic acid, and capryloyl salicylic acid, which is one of the lipo-hydroxy acids (LHA). Transparent appearance was stabilized by increasing the solubility of lipophilic salicylic acid and capryloyl salicylic acid in water using ethanol, polyol, and sodium hydroxide, and supplementing suspension and deposition using a double micelle structure of two types of PEG surfactants. Cleansing water applied with this technology was developed, and makeup removing ability and skin texture improvement ability were confirmed using an optical camera and an image analyzer. This solubilization technology is proposed as a new approach of LHA, which has been difficult to apply due to its low solubility in water, and is expected to help in the development of new chemical peeling products.

Development of Adsorbent for Vapor Phase Elemental Mercury and Study of Adsorption Characteristics (증기상 원소수은의 흡착제 개발 및 흡착특성 연구)

  • Cho, Namjun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.1-6
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    • 2021
  • Mercury, once released, is not destroyed but accumulates and circulates in the natural environment, causing serious harm to ecosystems and human health. In the United States, sulfur-impregnated activated carbon is being considered for the removal of vapor mercury from the flue gas of coal-fired power plants, which accounts for about 32 % of the anthropogenic emissions of mercury. In this study, a high-efficiency porous mercury adsorption material was developed to reduce the mercury vapor in the exhaust gas of coal combustion facilities, and the mercury adsorption characteristics of the material were investigated. As a result of the investigation of the vapor mercury adsorption capacity at 30℃, the silica nanotube MCM-41 was only about 35 % compared to the activated carbon Darco FGD commercially used for mercury adsorption, but it increased to 133 % when impregnated with 1.5 % sulfur. In addition, the furnace fly ash recovered from the waste copper regeneration process showed an efficiency of 523 %. Furthermore, the adsorption capacity was investigated at temperatures of 30 ℃, 80 ℃, and 120 ℃, and the best adsorption performance was found to be 80 ℃. MCM-41 is a silica nanotube that can be reused many times due to its rigid structure and has additional advantages, including no possibility of fire due to the formation of hot spots, which is a concern when using activated carbon.

Effect of Water Soluble fraction from Japanese Larch Wood on Sawdust Cultivation of Lentinula edodes (일본잎갈나무재의 수용성추출물 첨가가 표고버섯의 톱밥재배에 미치는 영향)

  • Cho, Nam-Seok;Chung, Hung-Chae;Kim, Dong-Hun;Lee, Sang-Sun;Ohga, Shoji;Leonowicz, A.
    • Journal of the Korean Wood Science and Technology
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    • v.32 no.1
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    • pp.35-44
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    • 2004
  • The water soluble fractions(WSF) from Japanese larch wood were isolated, purified by anion exchange resin and Sephadex gel filtration and identified its chemical structure by means of periodate oxidation and methylation reactions. Its major components are arabinose and galactose (1 : 3.4). Based on the results of periodate oxidation, methylation and gas chromatographic analysis of purified WSF, main chain is composed of β-1,3-glycosidic linkage among D-galactopyranoses, and two different side chains; β-1,6-glycosidic linkage among 2-3 units of D-galactopyranoses and β-1,6-glycosidic linkage between 1-2 units of D-galactopyranose and L-arabinopyranose. Addition of WSF to culture media of oak mushroom (Lentinula edodes) accelerated the mycelial growth. In the case of PDA cultures, 2 percent addition of WSF in Sanlim No. 6 strain and 4 percent of WSF in Mok-H strain mostly enhanced the mycelial growth of the mushroom. In the case of sawdust cultures, 4 percent addition of WSF in two strains showed the best mycelial growth. High percentages addition of WSF inhibited mycelial growth of the mushroom. Mushroom production was increased with addition of WSF. By the addition of WSF, ergosterol contents in the media were quite high at the colonized stage and rapidly increased at the fruiting stage. Therefore the ergosterol content could be utilized as an indicator to evaluate the culture maturity for the mushroom fruiting.

Tuning of the Interparticle interactions in ultrafine ferrihydrite nanoparticles

  • Knyazev, Yuriy V.;Balaev, Dmitry A.;Yaroslavtsev, Roman N.;Krasikov, Aleksandr A.;Velikanov, Dmitry A.;Mikhlin, Yuriy L.;Volochaev, Mikhail N.;Bayukov, Oleg A.;Stolyar, Sergei V.;Iskhakov, Rauf S.
    • Advances in nano research
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    • v.12 no.6
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    • pp.605-616
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    • 2022
  • We prepared two samples of ultrafine ferrihydrite (FH) nanoparticle ensembles of quite a different origin. First is the biosynthesized sample (as a product of the vital activity of bacteria Klebsiella oxytoca (hereinafter marked as FH-bact) with a natural organic coating and negligible magnetic interparticle interactions. And the second one is the chemically synthesized ferrihydrite (hereinafter FH-chem) without any coating and high level of the interparticle interactions. The interparticle magnetic interactions have been tuned by modifying the nanoparticle surface in both samples. The coating of the FH-bact sample has been partially removed by annealing at 150℃ for 24 h (hereinafter FH-annealed). The FH-chem sample, vice versa, has been coated (1.0 g) with biocompatible polysaccharide (arabinogalactan) in an ultrasonic bath for 10 min (hereinafter FH-coated). The changes in the surface properties of nanoparticles have been controlled by XPS. According to the electron microscopy data, the modification of the nanoparticle surface does not drastically change the particle shape and size. A change in the average nanoparticle size in sample FH-annealed to 3.3 nm relative to the value in the other samples (2.6 nm) has only been observed. The estimated particle coating thickness is about 0.2-0.3 nm for samples FH-bact and FH-coated and 0.1 nm for sample FH-annealed. Mössbauer and magnetization measurements are definitely shown that the drastic change in the blocking temperature is caused by the interparticle interactions. The experimental temperature dependences of the hyperfine field hf>(T) for samples FH-bact and FH-coated have not revealed the effect of interparticle interactions. Otherwise, the interparticle interaction energy Eint estimated from the hf>(T) for samples FH-chem and FH-annealed has been found to be 121kB and 259kB, respectively.

Technology Trends of Smart Abnormal Detection and Diagnosis System for Gas and Hydrogen Facilities (가스·수소 시설의 스마트 이상감지 및 진단 시스템 기술동향)

  • Park, Myeongnam;Kim, Byungkwon;Hong, Gi Hoon;Shin, Dongil
    • Journal of the Korean Institute of Gas
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    • v.26 no.4
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    • pp.41-57
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    • 2022
  • The global demand for carbon neutrality in response to climate change is in a situation where it is necessary to prepare countermeasures for carbon trade barriers for some countries, including Korea, which is classified as an export-led economic structure and greenhouse gas exporter. Therefore, digital transformation, which is one of the predictable ways for the carbon-neutral transition model to be applied, should be introduced early. By applying digital technology to industrial gas manufacturing facilities used in one of the major industries, high-tech manufacturing industry, and hydrogen gas facilities, which are emerging as eco-friendly energy, abnormal detection, and diagnosis services are provided with cloud-based predictive diagnosis monitoring technology including operating knowledge. Here are the trends. Small and medium-sized companies that are in the blind spot of carbon-neutral implementation by confirming the direction of abnormal diagnosis predictive monitoring through optimization, augmented reality technology, IoT and AI knowledge inference, etc., rather than simply monitoring real-time facility status It can be seen that it is possible to disseminate technologies such as consensus knowledge in the engineering domain and predictive diagnostic monitoring that match the economic feasibility and efficiency of the technology. It is hoped that it will be used as a way to seek countermeasures against carbon emission trade barriers based on the highest level of ICT technology.

Phenolic compounds from the flowers of Cosmos bipinnatus and their anti-atopic activity (코스모스(Cosmos bipinnatus) 꽃으로부터 phenolic 화합물의 분리 동정과 항아토피 효과)

  • Jeon, Hyeong-Ju;Kim, Hyoung-Geun
    • Journal of Applied Biological Chemistry
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    • v.65 no.3
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    • pp.215-219
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    • 2022
  • The flowers of Cosmos bipinnatus were extracted with solvent made with methanol:water (4:1) and the concentrates were partitioned into ethyl acetate (EtOAc), n-butanol (n-BuOH), and water (H2O) fractions. The octadecyl silica gel (ODS) and silica gel (SiO2) column chromatographies were repeated for the EtOAc fraction to isolated of two phenolic compounds. The chemical structure of the isolated compounds were identified as benzyl O-β-ᴅ-glucopyranoside (1), and 2-phenylethyl O-β-ᴅ-glucopyranoside (2) through spectroscopic datas such as nuclear magnetic resornance, infrarad spectroscopy, and mass spectroscopy. These two compounds were first isolated from C. bipinnatus flowers through this study. To evaluate the anti-atopic activity of the two isolated compounds using a HaCaT cell line induced by ultraviolet light, several experiments were conducted and neither both compounds showed toxicity in the concentration range of 1 to 1,000 ㎍/mL. In the results of anti-atopic activity through Thymus and activation regualted chemokine (TARC) assay, both compounds showed dose-dependent TARC inhibitory activity. In particular, compound 1 showed significant activity even in a low concentration range of 10 ㎍/mL, and in different concentration ranges. Also compound 1 showed higher inhibitory activity than other compound, confirming that the anti-atopic activity was the most excellent. Based on these results, it is considered that it can be used as a functional cosmetic material.

Anti-atopic dermatitis effects of Parasenecio auriculatus via simultaneous inhibition of multiple inflammatory pathways

  • Kwon, Yujin;Cho, Su-Yeon;Kwon, Jaeyoung;Hwang, Min;Hwang, Hoseong;Kang, Yoon Jin;Lee, Hyeon-Seong;Kim, Jiyoon;Kim, Won Kyu
    • BMB Reports
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    • v.55 no.6
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    • pp.275-280
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    • 2022
  • The treatment of atopic dermatitis (AD) is challenging due to its complex etiology. From epidermal disruption to chronic inflammation, various cells and inflammatory pathways contribute to the progression of AD. As with immunosuppressants, general inhibition of inflammatory pathways can be effective, but this approach is not suitable for long-term treatment due to its side effects. This study aimed to identify a plant extract (PE) with anti-inflammatory effects on multiple cell types involved in AD development and provide relevant mechanistic evidence. Degranulation was measured in RBL-2H3 cells to screen 30 PEs native to South Korea. To investigate the anti-inflammatory effects of Parasenecio auriculatus var. matsumurana Nakai extract (PAE) in AD, production of cytokines and nitric oxide, activation status of FcεRI and TLR4 signaling, cell-cell junction, and cell viability were evaluated using qRT-PCR, western blotting, confocal microscopy, Griess system, and an MTT assay in RBL-2H3, HEK293, RAW264.7, and HaCaT cells. For in vivo experiments, a DNCBinduced AD mouse model was constructed, and hematoxylin and eosin, periodic acid-Schiff, toluidine blue, and F4/80-staining were performed. The chemical constituents of PAE were analyzed by HPLC-MS. By measuring the anti-degranulation effects of 30 PEs in RBL-2H3 cells, we found that Paeonia lactiflora Pall., PA, and Rehmannia glutinosa (Gaertn.) Libosch. ex Steud. show an inhibitory activity of more than 50%. Of these, PAE most dramatically and consistently suppressed cytokine expression, including IL-4, IL-9, IL-13, and TNF-α. PAE potently inhibited FcεRI signaling, which mechanistically supports its basophil-stabilizing effects, and PAE downregulated cytokines and NO production in macrophages via perturbation of toll-like receptor signaling. Moreover, PAE suppressed cytokine production in keratinocytes and upregulated the expression of tight junction molecules ZO-1 and occludin. In a DNCB-induced AD mouse model, the topical application of PAE significantly improved atopic index scores, immune cell infiltration, cytokine expression, abnormal activation of signaling molecules in FcεRI and TLR signaling, and damaged skin structure compared with dexamethasone. The anti-inflammatory effect of PAE was mainly due to integerrimine. Our findings suggest that PAE could potently inhibit multi-inflammatory cells involved in AD development, synergistically block the propagation of inflammatory responses, and thus alleviate AD symptoms.