• Title/Summary/Keyword: Biological Engineering

Search Result 9,444, Processing Time 0.044 seconds

Issues in IT Rheology

  • Ahn Kyung-Hyun;Lee Seung-Jong
    • Proceedings of the Korean Society of Rheology Conference
    • /
    • 2006.06a
    • /
    • pp.15-15
    • /
    • 2006
  • PDF

Application of Biofilter Using Fibril-form Matrix for Odor Gas Removal

  • Lee, Gwang-Yeon;Jeong, Gwi-Taek;Lee, Kyoung-Min;Snuwoo, Chang-Shin;Lee, Woo-Tae;Cha, Jin-Myoung;Jang, Young-Seon;Park, Don-Hee
    • 한국생물공학회:학술대회논문집
    • /
    • 2005.04a
    • /
    • pp.247-251
    • /
    • 2005
  • This research was performed for developing of biological treatment process of odor gas such as MEK, $H_{2}S$, and toluene, which is generated from the food waste recycling process. To establish the operational conditions of odor gas removal by small-scale biofiltration equipment, it was continuously operated by using toluene as a treating odor object. When the odor treating microorganisms were adhered to fibril form biofilter, high removal efficiency over 93% was obtained by biofilm formation. At 400 ppm of inlet odor gas concentration and 10 sec of retention time, the removal efficiency was 76% and 93% in 1st stage reactor and 2nd stage reactor, respectively. However, the removal efficiency remained over 97% at the operational conditions above 15 sec of retention time.

  • PDF

Isolation, Identification and Biological Control Activity of SKU-78 Strain against Ralstonia solanacearum (풋마름병균, Ralstonia solanacearum의 길항세균 SKU-78 균주의 분리 동정 및 특성)

  • Sung, Pil-Je;Shin, Jeong-Kun;Cho, Hong-Bum;Kim, Shin-Duk
    • Applied Biological Chemistry
    • /
    • v.48 no.1
    • /
    • pp.48-52
    • /
    • 2005
  • Six stains of plant growth promoting rhizobacteria were selected through germinating seed assay and root colonization assay. Among them, SKU-78 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 60% reduction of bacterial wilt disease compared with the control. It was suggested that SKU-78 strain activated the host defense systems in plants, based on lack of direct antibiosis against pathogen. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, SKU-78 stain was identified as Bacillus sp. SKU-78.

High Alloying Degree of Carbon Supported Pt-Ru Alloy Nanoparticles Applying Anhydrous Ethanol as a Solvent

  • Choi, Kwang-Hyun;Lee, Kug-Seung;Jeon, Tae-Yeol;Park, Hee-Young;Jung, Nam-Gee;Chung, Young-Hoon;Sung, Yung-Eun
    • Journal of Electrochemical Science and Technology
    • /
    • v.1 no.1
    • /
    • pp.19-24
    • /
    • 2010
  • Alloying degree is an important structural factor of PtRu catalysts for direct methanol fuel cells (DMFC). In this work, carbon supported PtRu catalysts were synthesized by reduction method using anhydrous ethanol as a solvent and $NaBH_4$ as a reducing agent. Using anhydrous ethanol as a solvent resulted in high alloying degree and good dispersion. The morphological structure and crystallanity of synthesized catalysts were characterized by X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM). CO stripping and methanol oxidation reaction were measured. Due to high alloying degree catalyst prepared in anhydrous ethanol, exhibited low onset potential for methanol oxidation and negative peak shift of CO oxidation than commercial sample. Consequently, samples, applying ethanol as a solvent, exhibited not only enhanced CO oxidation, but also increased methanol oxidation reaction (MOR) activity compared with commercial PtRu/C (40 wt%, E-tek) and 40 wt% PtRu/C prepared in water solution.

End-to-end Structural Restriction of α-Synuclein and Its Influence on Amyloid Fibril Formation

  • Hong, Chul-Suk;Park, Jae Hyung;Choe, Young-Jun;Paik, Seung R.
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.12
    • /
    • pp.3542-3546
    • /
    • 2014
  • Relationship between molecular freedom of amyloidogenic protein and its self-assembly into amyloid fibrils has been evaluated with ${\alpha}$-synuclein, an intrinsically unfolded protein related to Parkinson's disease, by restricting its structural plasticity through an end-to-end disulfide bond formation between two newly introduced cysteine residues on the N- and C-termini. Although the resulting circular form of ${\alpha}$-synuclein exhibited an impaired fibrillation propensity, the restriction did not completely block the protein's interactive core since co-incubation with wild-type ${\alpha}$-synuclein dramatically facilitated the fibrillation by producing distinctive forms of amyloid fibrils. The suppressed fibrillation propensity was instantly restored as the structural restriction was unleashed with ${\beta}$-mercaptoethanol. Conformational flexibility of the accreting amyloidogenic protein to pre-existing seeds has been demonstrated to be critical for fibrillar extension process by exerting structural adjustment to a complementary structure for the assembly.

Influence of Amorphous Polymer Nanoparticles on the Crystallization Behavior of Poly(vinyl alcohol) Nanocomposites

  • Lee, Kyung-Jin;Lee, Ji-Hye;Hong, Jin-Yong;Jang, Jyong-Sik
    • Macromolecular Research
    • /
    • v.17 no.7
    • /
    • pp.476-482
    • /
    • 2009
  • The crystallization behavior of poly(vinyl alcohol) (PVA) in the presence and absence of polypyrrole nanoparticles (PPy NPs) was investigated in terms of the heterogeneous nucleation effect of PPy NPs using FTIR, X-ray diffraction, differential scanning calorimeter and polarized optical microscope analysis. PPy NPs were prepared by dispersion polymerization method stabilized by PVA in aqueous solution. A polymer nanocomposite with uniform dispersity could be readily obtained due to the enhanced compatibility between the filler and matrix. Compared with the PPy NP-absent PVA, the PPy NP/PVA nanocomposite exhibited an enhanced degree of crystallinity. The degree of crystallinity increased up to 17% at the PPy NP concentration of 1 wt%, compared to the pristine PVA. The PPy NP acted as an effective nucleating agent during the crystallization process, thereby enhancing the degree and rate of crystallization. The kinetics study of the crystallization also revealed the decreased value of the Avrami coefficient in the case of the PPy NP/PVA nanocomposite.

Synthesis of Nitrogen-Doped Porous Carbon Fibers Derived from Coffee Waste and Their Electrochemical Application (커피 폐기물 기반의 질소가 포함된 다공성 탄소 섬유의 제조 및 전기화학적 응용)

  • Dong Hyun Kim;Min Sang Kim;Suk Jekal;Jiwon Kim;Ha-Yeong Kim;Yeon-Ryong Chu;Chan-Gyo Kim;Hyung Sub Sim;Chang-Min Yoon
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.31 no.1
    • /
    • pp.57-68
    • /
    • 2023
  • In this study, coffee waste was recycled into nitrogen-doped porous carbon fibers as an active material for high-energy EDLC (Electric Double Layer Capacitors). The coffee waste was mixed with polyvinylpyrrolidone and dissolved into dimethylformamide. The mixture was then electrospun to fabricate coffee waste-derived nanofibers (Bare-CWNF), and carbonization process was followed under a nitrogen atmosphere at 900℃. Similar to Bare-CWNF, the as-synthesized carbonized coffee waste-derived nanofibers (Carbonized-CWNF) maintained its fibrous form while preserving the composition of nitrogen. The electrochemical performance was analyzed for carbonized coffee waste (Carbonized-CW)-, carbonized PAN-derived nanofibers (Carbonized-PNF)-, and Carbonized-CWNF-based electrodes in the operating voltage window of -1.0-0.0V, Among the electrodes, Carbonized-CWNF-based electrodes exhibited the highest specific capacitance of 123.8F g-1 at 1A g-1 owing to presence of nitrogen and porous structure. As a result, nitrogen-contained porous carbon fibers synthesized from coffee waste showed excellent electrochemical performance as electrodes for high-energy EDLC. The experimental designed in this study successfully demonstrated the recycling of the coffee waste, one of the plant-based biomass that causes the environmental pollution into high-energy materials, also, attaining the ecofriendliness.

Response of Shewanella oneidensis MR-1 to Longterm Exposure with Toxic Ionic Liquid: Comparative Studies on MR-1 and SH-1, an Acclimated Strain (유독 이온성 액체의 장기 노출에 대한 Shewanella oneidensis MR-1의 반응: MR-1과 순응된 균주 SH-1의 비교 연구)

  • Han, Sang Hyun;Kang, Chang-Ho;Kwak, Dae Yung;Ha, Sung Ho;Koo, Yoon-Mo;So, Jae-Seong
    • KSBB Journal
    • /
    • v.28 no.2
    • /
    • pp.146-150
    • /
    • 2013
  • In this study, we investigated the effects of longterm exposure to ionic liquid (IL) on Shewanella oneidensis MR-1 (MR-1). MR1 was acclimated through repeated exposure to IL. The acclimated strain was named as S. oneidensis SH-1 (SH-1) and compared with MR-1 in various aspects including morphology, cell surface hydrophobicity (CSH), motility, and fatty acid. Compared to the MR-1, SH-1 showed elongated cell shape on scanning electron microscopy. Upon exposure to IL, hydrophobicity of SH-1 (28.2%) was higher that of MR-1 (3.3%). In contrast, motility of SH-1 (7 mm) was lower than that also of MR-1 (22 mm), and branched chain fatty acid of SH-1 was lower than that of MR-1, 27.6% and 41.1%, respectively.