• Title/Summary/Keyword: BET study

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Fabrication of a High Porous Polyethylene Membrane Using BET as a Novel Diluent (새로운 BET 희석제를 이용한 고다공성 폴리에틸렌 분리막 제조)

  • Cho, Inhyun;Lee, Soomi;Kim, Chang Keun
    • Polymer(Korea)
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    • v.38 no.4
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    • pp.530-534
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    • 2014
  • Polyethylene (PE) membranes having various porosities are used as microfilters and separators in lithium ion batteries. Membranes having a high porosity are required for use as separators in a large scale lithium ion secondary battery. In this study, BET was examined for use as a new nontoxic diluent for the fabrication of highly porous PE membranes by thermally induced phase separation process. It was confirmed that BET can be used as a new diluent for the fabrication of the PE membranes by exploring upper critical solution temperature type phase behavior of PE mixtures with BET. When the porosity of the membrane prepared from the PE/PO mixture was compared with that prepared from PE/BET mixture, the latter was about 1.8 times higher than the former.

A Statistical-Mechanical Study on Multilayer Adsorptions and the BET Adsorption Equation (다분자층 흡착과 BET 흡착식의 통계 역학적 고찰)

  • Lim, Kyung-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.23 no.4
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    • pp.280-289
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    • 2006
  • Multilayer adsorptions and BET adsorption are analyzed statistical-mechanically. Which ensemble is selected for the analysis is unimportant, because each ensemble yields the same results. However, the amount of mathematical manipulations and the matter of convenience vary from ensemble to ensemble. Hence, multilayer adsorptions and BET adsorption are examined using a canonical and a grand canonical ensembles, and an ensemble of subsystems. Also, the characteristics of multilayer and BET adsorptions are delineated.

Transcriptome analysis of iBET-151, a BET inhibitor alone and in combination with paclitaxel in gastric cancer cells

  • Kang, Sun Kyoung;Bae, Hyun Joo;Kwon, Woo Sun;Che, Jingmin;Kim, Tae Soo;Chung, Hyun Cheol;Rha, Sun Young
    • Genomics & Informatics
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    • v.18 no.4
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    • pp.37.1-37.11
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    • 2020
  • BET inhibitor, as an epigenetic regulator inhibitor, reduces the expression of oncogenes such as Myc and Bcl-2, which affects cancer growth and development. However, it has modest activity because of the narrow therapeutic index. Therefore, combination therapy is necessary to increase the anti-tumor effect. Paclitaxel, an anti-mitotic inhibitor, is used as second-line therapy for gastric cancer (GC) as a monotherapy or combination. In this study, we performed RNA sequencing of GC cells treated with iBET-151 and/or paclitaxel to identify the differentially expressed genes associated with possible mechanisms of synergistic effect. We also performed Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses to determine the most enriched terms and pathways of upregulated and downregulated genes. We found 460 genes in which iBET-151 and paclitaxel combination treatment changed more than single-treatment or no-treatment. Thus, additional functional studies are needed, but our results provide the first evidence of the synergistic effect between iBET-151 and paclitaxel in regulating the transcriptome of GC cells.

Effect of methyl donors supplementation on performance, immune responses and anti-oxidant variables in broiler chicken fed diet without supplemental methionine

  • Savaram, Venkata Rama Rao;Mantena, Venkata Lakshmi Narasimha Raju;Bhukya, Prakash;Paul, Shyam Sunder;Devanaboyina, Nagalakshmi
    • Animal Bioscience
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    • v.35 no.3
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    • pp.475-483
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    • 2022
  • Objective: Methionine (Met) is involved in methyl group transfer besides protein synthesis. As the availability is limited and cost is high for synthetic Met, reductions in its inclusion in broiler diet may be possible by supplementing the low Met diets with methyl donors (MD) like betaine (Bet), folic acid (FA), vitamin B12 (B12), and biotin (Bio). An experiment was conducted to study the effects of supplementing the MD on performance (average daily gain [ADG], daily feed intake, feed efficiency [FE]), anti-oxidant variables, immune responses and serum protein concentration in broilers fed sub-optimal concentrations of dietary Met. Methods: Maize-soybean meal diet was used as control (CD). Different MD like Bet (0.2%), B12 (0.1 mg), FA (4 mg), or Bio (1.5 mg/kg) were supplemented to basal diet (BD) having no supplemental Met. The BD without MD was kept for comparison. Each diet was fed ad libitum to 10 replicates of 25 chicks in each from 1 to 42 d of age. Results: At the end of experiment, the ADG in MD group was higher than BD and lower than CD. The FE improved with FA or Bet compared to the BD. Breast meat weight was higher in Bet compared to the BD, while it was intermediate between BD and CD in other groups. The lipid peroxidation reduced with Bio, B12, or Bet, while the glutathione peroxidase activity improved with Bio or B12 compared to the BD. Lymphocyte proliferation improved with Bet compared to the BD. The serum protein concentrations increased with FA, Bio, or Bet compared to those fed BD. Conclusion: It can be concluded that the ADG can be improved partially with supplementation of MD while the FE improved with FA or Bet. Some MD also reduced the stress indices and improved immune responses compared to the BD fed broilers.

Influence of Surface Characteristics of Mesoporous Silica on Pb(II) and Cd(II) Adsorption Behavirous (Mesoporous silica의 표면특성이 Pb(II)와 Cd(II)의 흡착거동에 미치는 영향)

  • Lee, Ha-Young;Lee, Kamp-Du;Park, Sang-Won
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.6
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    • pp.673-679
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    • 2008
  • In this study, Mesoporous silica were prepared from hydrothermal synthesis using gel mixture of tetraethylorthosilcate (TEOS) as silica source and cetyltrimethylammonium bromide(CTMABr) as a template. In the optimum synthesis cause, molar ratio of template and silica changed. The surface and structure properties of Mesoporous silica were determined by XRD, SEM, and BET. N$_2$ adsorption isotherm characteristics, including the specific surface area(S$_{BET}$), total pore volume(V$_T$), and average pore diameter(D$_{BJH}$), were determined by BET. Also, the adsorption character of Pb(II) and Cd(II) ion on Mesoporous silica were measured using ICP. As a result, a SBET of 100$\sim$1,500 m$^2$/g was determined from the N$_2$ adsorption isotherm. Also, the average pore diameter of 2$\sim$4 nm. The adsorption of Pb ion and Cd ion on Mesoporous silica become different depending on the pH of solution. The adsorption amount of Mesoporus silica had higher than that of silicagel.

Development of a Cost-Effective 20K Hydrogen BET Measurement for Nanoporous Materials (나노다공체 물성 측정을 위한 극저온(20K) 수소 BET 개발 및 응용)

  • Park, Jaewoo;Oh, Hyunchul
    • Korean Journal of Materials Research
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    • v.27 no.9
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    • pp.466-470
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    • 2017
  • With the matters of climate change, energy security and resource depletion, a growing pressure exists to search for replacements for fossil fuels. Among various sustainable energy sources, hydrogen is thought of as a clean energy, and thus efficient hydrogen storage is a major issue. In order to realize efficient and safe hydrogen storage, various porous materials are being explored as solid-states materials for hydrogen storage. For those purposes, it is a prerequisite to characterize a material's textural properties to evaluate its hydrogen storage performance. In general, the textural properties of porous materials are analyzed by the Brunauer-Emmett-Teller (BET) measurement using nitrogen gas as a probe molecule. However, nitrogen BET analysis is sometimes not suitable for materials possessing small pores and surfaces with high curvatures like MOFs because the nitrogen molecule may sometimes be too large to reach the entire porous framework, resulting in an erroneous value. Hence, a smaller probe molecule for BET measurements (such as hydrogen) may be required. In this study, we describe a cost-effective novel cryostat for BET measurement that can reach temperatures below the liquefaction of hydrogen gas. Temperature and cold volume of the cryostat are corrected, and all measurements are validated using a commercial device. In this way, direct observation of the hydrogen adsorption properties is possible, which can translate directly into the determination of textural properties.

Characterization of Human Foamy Virus Integrase Mutant (인간 포미바이러스 인테그라제 돌연변이의 특성)

  • Kang Seung Yi;Oh Soo A;Lee Hak Sung;Han Sung Tai;Shin Cha-Gyun
    • YAKHAK HOEJI
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    • v.49 no.3
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    • pp.198-204
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    • 2005
  • Human foamy virus (HFV) integrase mediates integration of viral c-DNA into cellular DNA. In this process, HFV integrase recognizes its own viral DNA specifically and catalyzes insertion of viral c-DNA. In order to study catalytic domains and residues, three deletion mutants and two point mutants of HFV integrase were constructed and analyzed with respect to enzymatic activities. The C-terminal deletion mutant showed decreased enzymatic activities while the N-terminal deletion mutant lost the activities completely, indicating that the N-terminal domain is more important than the C-terminal domain in enzymatic reaction. The point mutants, in which an aspartic acid at the 164th position or a glutamic acid at the 200th position of the HFV integrase protein was changed to an alanine, lost the enzymatic activities completely. However, they were well complemented with other defective deletion mutants to recover enzymatic activities partially. Therefore, these results suggest that the aspartic acid and glutamic acid at the respective 164th and 200th positions are catalytic residues for enzymatic reaction.

Effect of Supplementing Betaine on Performance, Carcass Traits and Immune Responses in Broiler Chicken Fed Diets Containing Different Concentrations of Methionine

  • Rao, S.V. Rama;Raju, M.V.L.N.;Panda, A.K.;Saharia, Poonam;Sunder, G. Shyam
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.5
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    • pp.662-669
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    • 2011
  • An experiment was conducted with broiler (Cobb 400) male chicks (n = 480) to determine the effect of betaine (Bet) supplementation (0 and 800 mg/kg) to diets containing five concentrations (15, 18, 20, 22 and 24 g/kg crude protein, CP) of methionine (Met) in a $2{\times}5$ factorial study for performance, carcass traits, immune responses, and serum parameters. Each diet was fed ad libitum from 1 to 42 d of age to 8 replicates of 6 chicks. Birds were housed in battery brooders placed in an open-sided poultry shed. Body weight gain, feed intake, feed conversion efficiency and slaughter variables were recorded at 21 and 42 d of age. Serum biochemical profile, antibody production against Newcastle disease (ND) and lymphocyte proliferation ratio (LPR) were analysed at 42 d of age. Supplementing Bet to diets containing sub-optimal concentrations of Met (15 g/kg) improved weight gain and breast yield at 21 d of age (p<0.01), and feed conversion efficiency at 42 d of age (p<0.05). Feed efficiency at 21 d of age, body weight gain at 42 d of age, slaughter variables except breast yield at 21 d of age and ND antibody titres were not affected (p>0.05) by the interaction. LPR increased (p<0.05) with Bet supplementation at 20 g Met/kg CP equal to those broilers fed 24 g Met without Bet. Bet supplementation enhanced the concentrations of protein, globulin and cholesterol in serum of broilers fed sub-optimal concentrations of Met. Results suggested that Bet supplementation (800 mg/kg diet) enhanced growth (21 d), feed conversion efficiency (42 d), breast yield and lymphocyte proliferation in broilers fed a diet containing 15 g Met/kg CP.

A Study on the Sulfur-Resistant Catalysts for Water Gas Shift Reaction II. Effect of Alkali Metal Salt on the Activity of CoMo Catalyst (황에 저항성을 가지는 수성가스 전환반응 촉매의 연구 II. CoMo 촉매의 활성에 미치는 알칼리 금속염의 영향)

  • Kim, Joon Hee;Lee, Ho In
    • Journal of the Korean Chemical Society
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    • v.42 no.6
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    • pp.696-702
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    • 1998
  • The effect of alkali metal salt on the activity of Co-Mo catalyst which has high resistance to sulfur poisoning for water gas shift reaction(WGSR) was studied. Two groups of catalysts were prepared to investigate the effects of anion and cation in alkali metal salts. For K-doped catalysts made with various potassium salts having different anion, the catalytic activity was explained to depend mainly on the BET surface area. Among the catalysts prepared by various nitrates of alkali metal as precursor, the Li-doped catalyst showed the best activity, and the others did not make significant differences giving relatively low activities. And the change of BET surface area by varying the loading of alkali metal showed a similar trend to that of activity. In this case, the activity was dependent on both BET surface area and the ratio of $Mo^{6+}$ with a tetrahedral coordination symmetry to $Mo^{6+}$ with an octahedral one, $Mo^6+[T]/Mo^{6+}[O]$ value.

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Nanocomposite of Ethyl Cellulose Using Environment-Friendly Plasticizer (친환경 가소제를 첨가한 에틸 셀룰로오스 나노복합체)

  • Choi Sung Heon;Cho Mi Suk;Kim Dukjoon;Kim Ji-Heung;Lee Dong Hyun;Shim Sang Joon;Nam Jae-Do;Lee Youngkwan
    • Polymer(Korea)
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    • v.29 no.4
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    • pp.399-402
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    • 2005
  • In this study, ethyl cellulose (EC)/montmorilloniote(MMT) nanocomposite films plasticized with environmental-friendly plasticizer (BET, EBN, ESO) were prepared by melt process using Hakke mixer. The $T_g$ of plasticized EC films decreased from 122 to $71^{circ}C$ with the increase in the BET content up to 30 $wt\%$. The addition of 10 $wt\%$ epoxidized soybean oil (ESO) as the second plasticizer cause the further drop of $T_g$ from 81 to $61^{circ}C$. The plasticizer-effect of BET was better than that of EBN. When the plasticizer was added into the EC films, the mechanical properties of EC films was decreased, however the addition of monotmorillonite (MMT) into the EC films or the ring opening reaction of ESO plasticizer cause enhancement of mechanical properties.