• Title/Summary/Keyword: BET model

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Immunomodulatory Effects of β-1,3/1,6-glucan and Lactobacillus plantarum LM1004 on Atopic Dermatitis Models (아토피 피부염 모델에 대한 β-1,3/1,6-glucan과 Lactobacillus plantarum LM1004의 면역 조절 효과)

  • Kim, In Sung;Kim, Sung Hak;Kim, Jeong A;Yu, Da Yoon;Kim, Gwang Il;Park, Dong-Chan;Lim, Jong Min;Lee, Sang Suk;Choi, In Soon;Cho, Kwang Keun
    • Journal of Life Science
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    • v.28 no.1
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    • pp.17-25
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    • 2018
  • In this study, we examined the efficacy of the immune regulation of ${\beta}$-1,3/1,6-glucan and Lactobacillus plantarum LM1004 on atopic dermatitis models. The oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 on mice significantly decreased the amount of scratching, leakage to evans blue, and concentrations of serum immunoglobulin E (IgE) and histamine compared with the atopic dermatitis - induced group. When atopic dermatitis was induced, the transcription factors (GATA-3, retinoic acid-related orphan receptor ${\gamma}$ T [$ROR{\gamma}T$]) and cytokines (interleukin-4 [IL-4], IL-17) of Th2 and Th17 cells were overexpressed at the transcriptional level, and they significantly decreased with oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004. In addition, ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 were shown to modulate the immune balance by increasing the expression of Th1 and Treg transcription (T-bet, forkhead box p3 [Foxp3]) and cytokines (interferon-${\gamma}$ [IFN-${\gamma}$], transforming growth factor-${\beta}$ [TGF-${\beta}$]). Galectin-9 and filaggrin were significantly lower in the atopic dermatitis - induced group and significantly higher in the ${\beta}$-1,3/1,6-glucan-treated group. In contrast, thymic stromal lymphopoietin (TSLP) was highest in the atopic dermatitis-induced group, while mice that were orally administered ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 showed similar TSLP levels to the control group. These results indicate that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 have immunomodulatory effects and atopic dermatitis improvement effects in an animal model of atopic dermatitis. Therefore, it is expected that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 can be used as natural materials in the treatment of atopic dermatitis.

A Comparison Study of Alum Sludge and Ferric Hydroxide Based Adsorbents for Arsenic Adsorption from Mine Water (알럼 및 철수산화물 흡착제의 광산배수 내 비소 흡착성능 비교연구)

  • Choi, Kung-Won;Park, Seong-Sook;Kang, Chan-Ung;Lee, Joon Hak;Kim, Sun Joon
    • Economic and Environmental Geology
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    • v.54 no.6
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    • pp.689-698
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    • 2021
  • Since the mine reclamation scheme was implemented from 2007 in Korea, various remediation programs have been decontaminated the pollution associated with mining and 254 mines were managed to reclamation from 2011 to 2015. However, as the total amount of contaminated mine drainage has been increased due to the discovery of potential hazards and contaminated zone, more efficient and economical treatment technology is required. Therefore, in this study, the adsorption properties of arsenic was evaluated according to the adsorbents which were derived from water treatment sludge(Alum based adsorbent, ABA-500) and granular ferric hydroxide(GFH), already commercialized. The alum sludge and GFH adsorbents consisted of aluminum, silica materials and amorphous iron hydroxide, respectively. The point of zero charge of ABA-500 and GFH were 5.27 and 6.72, respectively. The result of the analysis of BET revealed that the specific surface area of GFH(257 m2·g-1) was larger than ABA-500(126~136 m2·g-1) and all the adsorbents were mesoporous materials inferred from N2 adsorption-desorption isotherm. The adsorption capacity of adsorbents was compared with the batch experiments that were performed at different reaction times, pH, temperature and initial concentrations of arsenic. As a result of kinetic study, it was confirmed that arsenic was adsorbed rapidly in the order of GFH, ABA-500(granule) and ABA-500(3mm). The adsorption kinetics were fitted to the pseudo-second-order kinetic model for all three adsorbents. The amount of adsorbed arsenic was increased with low pH and high temperature regardless of adsorbents. When the adsorbents reacted at different initial concentrations of arsenic in an hour, ABA-500(granule) and GFH could remove the arsenic below the standard of drinking water if the concentration was below 0.2 mg·g-1 and 1 mg·g-1, respectively. The results suggested that the ABA-500(granule), a low-cost adsorbent, had the potential to field application at low contaminated mine drainage.

Changes of Amino Acids and Formation Mechanism of Flavor in Cooked Small Shrimps (새우 가열(加熱)중의 아미노산의 변화(變化) 및 향기성분(香氣成分) 생성기구(生成機構)에 관한 연구(硏究))

  • Choi, Sung-Hee;Lee, Byung-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.4
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    • pp.371-378
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    • 1987
  • Free and total amino acids of before and after the heating of the small shrimps were analysed quantitatively, in order to confirm the role of amino acids as important precursors of cooked odor components. Differences of free amino acids contents of the three samples were slightly reconized but free amino acids contents of all sample decreased as about half by heating, It seems that decreased amino acids participate In volatile components of the Small Shrimps. (Sergia lucens Hancen, Euphausia Surperba and Euphausia pacifica Hancen). The amino-carbonyl model reaction was carried out, in order to confirm formation mechanism of volatile compounds of the small shrimps during cooking. The model systems constituted by diluted solutions. of glucose and amino acids (proline, taurine and betaine) the most containing in small shrimps. The volatile odor concentrates of model system were obtained by simultaneous distillation and extraction with Nickerson's apparatus. The odor concentrates of model systems(I, III) had not small shrimp-like odor and main compounds were 1,4,5,6-tetrahydro-2-acetopyridine and 2-acetyl pyridine. In model system II, hetero ring nitrogen and sulfur compounds identified in small shrimps were not did.

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Adsorption of p-Xylene by Expanded Graphite (팽창흑연을 이용한 p-Xylene 흡착)

  • Lee, Chae-Young;Jee, Hyeong-Sub;Chung, Jae-Woo;Kim, Sang-Hyoun;Cho, Yun-Chul;Kang, Seok-Tae
    • Journal of the Korean GEO-environmental Society
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    • v.13 no.5
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    • pp.35-40
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    • 2012
  • In this study, adsorption characteristics of expanded graphite (EG) were investigated by a series of batch adsorption tests using p-Xylene as a model volatile organic compounds (VOCs). After acid treatment, graphite were expanded at various temperature from $600^{\circ}C$ to $1000^{\circ}C$ for one minute. The optimal temperature was $800^{\circ}C$, where the expansion ratio reached 195 times of original volume. The BET specific surface area of EG was $92.4m^2/g$, which was only 1/10 of granular activated carbon (GAC), however the adsorption of p-Xylene by EG was almost completed within 5 minutes while that of GAC continued for 7 days because the majority of pores of EG was consisted with meso- and macro-pores. According to the Langmuir isotherm analysis, the maximum specific adsorption of p-Xylene onto EG was 24.0 mg/L with the adsorption constant of 7.94. In conclusion, the adsorption capacity of EG was much less than that of GAC due to the significantly lower specific surface area, but the first order kinetic constant was more than 500 times larger than GAC. Overall, EG might be effective where the fast adsorption is required.

Physicochemical Properties and Cu Sorption of the Biochar Derived from Woody Biomass (목질계 바이오매스에서 생산된 바이오차의 물리화학적 특성 및 Cu 흡착제거 특성)

  • Park, Yi-Kyung;Yang, Jae-Kyu;Na, Jung-Kyun;Jung, Jong-Am;Jung, Hyung-Jin;Kang, Chang-Hwan;Ko, Kyung-Min;Kim, Wan-Hee;Chang, Yoon-Young
    • Journal of Soil and Groundwater Environment
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    • v.17 no.2
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    • pp.54-61
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    • 2012
  • In this study, the adsorption of $Cu^{2+}$ from aqueous solution by the biochar derived from woody biomass at different pyrolysis temperatures has been investigated. The woody biomass wastes used in this study were branch of willow ($Salix$ $koreensis$ $Andersson$) and bark of chestnut ($Castanea$ $crenata$ $var.$ $dulcis$). Three biochar samples prepared by heating each biomass at temperature of $300^{\circ}C$, $500^{\circ}C$, and $700^{\circ}C$were tested for the adsorption capacity of Cu. Also the physicochemical properties of the developed biochars were studied using different characterization techniques such as FT-IR, SEM, BET surface area, and cation exchange capacity (CEC). The adsorption of Cu could be well described by Langmuir model for both willow and chestnut biochars with $R^2{\geq}0.98$. The maximum adsorption capacities of the biochar produced at $700^{\circ}C$ from the Langmuir equation were found to be 12.5 mg $g^{-1}$ and 16.9 mg $g^{-1}$ for willow and chestnut, respectively. Chestnut biochar was found to interact more effectively with the active sites available for Cu, resulting higher removal of Cu(II) than wiloow biochar. Ion exchange and surface complexation found to be the main mechanisms involved in the adsorption process. This study demonstrated the feasibility of the biochars derived from woody biomass to be as a low-cost potential adsorbent for heavy metals as Cu(II) removal in aquatic system.

Nickel Catalysts Supported on Ash-Free Coal for Steam Reforming of Toluene (무회분탄에 분산된 니켈 촉매의 톨루엔 수증기 개질)

  • PRISCILLA, LIA;KIM, SOOHYUN;YOO, JIHO;CHOI, HOKYUNG;RHIM, YOUNGJOON;LIM, JEONGHWAN;KIM, SANGDO;CHUN, DONGHYUK;LEE, SIHYUN
    • Journal of Hydrogen and New Energy
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    • v.29 no.6
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    • pp.559-569
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    • 2018
  • Catalytic supports made of carbon have many advantages, such as high coking resistance, tailorable pore and surface structures, and ease of recycling of waste catalysts. Moreover, they do not require pre-reduction. In this study, ash-free coal (AFC) was obtained by the thermal extraction of carbonaceous components from raw coal and its performance as a carbon catalytic support was compared with that of well-known activated carbon (AC). Nickel was dispersed on the carbon supports and the resulting catalysts were applied to the steam reforming of toluene (SRT), a model compound of biomass tar. Interestingly, nickel catalysts dispersed on AFC, which has a very small surface area (${\sim}0.13m^2/g$), showed higher activity than those dispersed on AC, which has a large surface area ($1,173A/cm^2$). X-ray diffraction (XRD) analysis showed that the particle size of nickel deposited on AFC was smaller than that deposited on AC, with the average values on AFC ${\approx}11nm$ and on AC ${\approx}23nm$. This proved that heteroatomic functional groups in AFC, such as carboxyls, can provide ion-exchange or adsorption sites for the nano-scale dispersion of nickel. In addition, the pore structure, surface morphology, chemical composition, and chemical state of the prepared catalysts were analyzed using Brunauer-Emmett-Taylor (BET) analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, and temperature-programmed reduction (TPR).

A Study on effects of emotional labor and emotional intelligence of dental hygienist on organizational effectiveness (치과위생사의 감정노동과 감성지능이 조직유효성에 미치는 영향 연구)

  • Kim, Young-Im
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.9
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    • pp.390-396
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    • 2019
  • This study was undertaken to analyze factors influencing the emotional labor and emotional intelligence of a dental hygienist on organizational effectiveness. The study was conducted between September 4, 2018 to December 7, 2018, enrolling a total of 233 dental hygienists living in the Jeollabuk-do province. The data were analyzed by independent t-test, one-way ANOVA, $Scheff{\acute{e}}$ test, Pearson's correlation coefficient, and stepwise multiple regression, using SPSS 18.0. The regression model obtained was F=138.917, P<0.05, with an explanatory percentage of 58.2. Emotional labor (${\beta}=0.608$) was determined to be the most influential variable among independent variables, and other factors affecting the organizational effectiveness of a dental hygienist include the highest level of education, career, and emotional intelligence. We conclude that in order to improve organizational effectiveness among dental hygienists, it is necessary to establish an effective plan for reducing emotional labor and promote emotional intelligence.

The Influence of Self-discrepancy in Virtual and Cross Worlds on Individuals' Activities in Online Communities (가상세계 및 공간간의 자기차이가 온라인 커뮤니티 활동에 미치는 영향에 관한 연구)

  • Lee, Ju-Min;Shin, Kyung-Shik;Suh, A-Young
    • The Journal of Society for e-Business Studies
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    • v.16 no.3
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    • pp.23-45
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    • 2011
  • People could possess different self-identity under virtual world from physical world because of anonymity of the virtual world and this difference could influence their behavior in the virtual world. Based on self-discrepancy theory, this research proposes that continuous use model in self-expression goal. We defined the difference bet ween actual self~identity and ideal self~identity in the virtual world as "self-discrepancy in virtual world", and the difference between actual self-identity in the physical world and actual self-identity in the virtual world as "cross-world self-discrepancy". Before testing hypothesis, we compare the actual self-identity in the online community with the actual self-identity in the physical world, and with ideal self-identity in the virtual world. We derived an index for two different types of self-identity in terms of Personal Self-identity and Social Self-identity through factor analysis. Our results show that online community members have a higher level of ideal self-identity than actual self-identity in online community, and they have better personal self-identity in online community than physical world while a lower level of social self-identity in online community than physical world. The results of the hypothesis testing analysis based on 300 respondents showed that "self-discrepancy in virtual world" negatively influenced perceived usefulness for self-expression while "cross-world self-discrepancy" positively influenced perceived usefulness for self-expression. The perceived usefulness for self-expression and ease of use positively influence both continuous use and knowledge contribution. Specially, the effect of perceived usefulness for self-expression on knowledge contribution is much bigger than the effect of ease of use. This study extends self-discrepancy theory to virtual worlds by suggesting various types of self-discrepancy and by applying the effect of self-discrepancies in online community. Also, this study extends technology acceptance model in the personal goal in terms of self-expression. This study hopes to offer practical insights by suggesting positive effect of self-discrepancy on behavior in the online community.

Adsorptive Removal of Radionuclide Cs+ in Water using Acid Active Clay (산활성 점토를 이용한 수중의 방사성 핵종 Cs+ 흡착 제거)

  • Lee, Jae Sung;Kim, Su Jin;Kim, Ye Eun;Kim, Seong Yun;Kim, Eun;Ryoo, Keon Sang
    • Journal of the Korean Chemical Society
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    • v.66 no.2
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    • pp.78-85
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    • 2022
  • Natural white clay was treated with 6 M of H2SO4 and heated at 80℃ for 6 h under mechanical stirring and the resulting acid active clay was used as an adsorbent for the removal of Cs+ in water. The physicochemical changes of natural white clay and acid active clay were observed by X-ray Fluorescence Spectrometry (XRF), BET Surface Area Analyser and Energy Dispersive X-line Spectrometer (EDX). While activating natural white clay with acid, the part of Al2O3, CaO, MgO, SO3 and Fe2O3 was dissolved firstly from the crystal lattice, which bring about the increase in the specific surface area and the pore volume as well as active sites. The specific surface area and the pore volume of acid active clay were roughly twice as high compared with natural white clay. The adsorption of Cs+ on acid active clay was increased rapidly within 1 min and reached equilibrium at 60 min. At 25 mg L- of Cs+ concentration, 96.88% of adsorption capacity was accomplished by acid active clay. The adsorption data of Cs+ were fitted to the adsorption isotherm and kinetic models. It was found that Langmuir isotherm was described well to the adsorption behavior of Cs+ on acid active clay rather than Freundlich isotherm. For adsorption Cs+ on acid active clay, the Langmuir isotherm coefficients, Q, was found to be 10.52 mg g-1. In acid active clay/water system, the pseudo-second-order kinetic model was more suitable for adsorption of Cs+ than the pseudo-first-order kinetic model owing to the higher correlation coefficient R2 and the more proximity value of the experimental value qe,exp and the calculated value qe,cal. The overall results of study showed that acid active clay could be used as an efficient adsorbent for the removal of Cs+ from water.

Study on Adsorption of PO43--P in Water using Activated Clay (활성 백토를 이용한 수중의 인산성 인(PO43--P) 흡착에 관한 연구)

  • Hwang, Ji Young;Jin, Ye Ji;Ryoo, Keon Sang
    • Journal of the Korean Chemical Society
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    • v.65 no.3
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    • pp.197-202
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    • 2021
  • In this study, activated clay treated with H2SO4 (20% by weight) and heat at 90 ℃ for 8 h for acid white soil was used as an adsorbent for the removal of PO43--P in water. Prior to the adsorption experiment, the characteristics of activated clay was examined by X-ray Fluorescence Spectrometry (XRF) and BET surface area analyser. The adsorption of PO43--P on activated clay was steeply increased within 0.25 h and reached equilibrium at 4 h. At 5 mg/L of low PO43--P concentration, roughly 98% of adsorption efficiency was accomplished by activated clay. The adsorption data of PO43--P were introduced to the adsorption isotherm and kinetic models. It was seen that both Freundlich and Langmuir isotherms were applied well to describe the adsorption behavior of PO43--P on activated clay. For adsorption PO43--P on activated clay, the Freundlich and Langmuir isotherm coefficients, KF and Q, were found to be 8.3 and 20.0 mg/g, respectively. The pseudo-second-order kinetics model was more suitable for adsorption of PO43--P in water/activated clay system owing to the higher correlation coefficient R2 and the more proximity value of the experimental value qe,exp and the calculated value qe,cal than the pseudo-first-order kinetics model. The results of study indicate that activated clay could be used as an efficient adsorbent for the removal of PO43-P from water.