• Title/Summary/Keyword: Specific capacity

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A study on Removal of $NH_3$ Gas in a Towar using a Ralu-Pack 250YC as a Packing Material (Ralu-Pack 250YC를 충전한 충전탑에서 암모니아가스 제거에 관한 연구)

  • 김석택
    • Journal of Environmental Science International
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    • v.9 no.5
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    • pp.389-392
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    • 2000
  • In this study a packed tower was selected for the treatment apparatus of $NH_3$ gas produced in industry. Formerly latticework packing has been used in preventive facility of treatment of $NH_3$ gas. However recently metallic Ralu-Pack 250YC. structured packing is usually being used in petrochemical production plant. This study is for the application the packing to the $NH_3$ gas treatment in wet scrubbing process. In Air/water system hydraulic pressure drop dependent of specific liquid load and gas capacity factor was continuous and parallel from graph. The tower height can be determuined by the number of transfer unit and the height of transfer unit influenced on liquid distribution.

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Effect of Mo-doped LiFePO4 Positive Electrode Material for Lithium Batteries

  • Oh, Seung-Min;Sun, Yang-Kook
    • Journal of Electrochemical Science and Technology
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    • v.3 no.4
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    • pp.172-177
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    • 2012
  • Mo-doped $LiFePO_4$ was synthesized via co-precipitation method using sucrose as the carbon source. Structure, surface morphology, and the electrochemical properties of the synthesized olivine compounds were investigated using Rietveld refinement of X-ray diffraction data (XRD), scanning electron microscopy (SEM), and electrochemical charge-ischarge tests. Spherical morphology with the particle size of ${\sim}8{\mu}m$ authenticated the enhanced tap density and volumetric energy density of the synthesized materials. Charge-discharge behavior of $LiFePO_4$ and Mo-doped $LiFePO_4$ cells demonstrated a specific capacity of 130 and 145 mAh $g^{-1}$, respectively. Mo-doped $LiFePO_4$ cells exhibited an excellent discharge capacity at 96 mAh $g^{-1}$ at 7 C-rate.

Progressive collapse analysis of two existing steel buildings using a linear static procedure

  • JalaliLarijani, Reza;Celikag, Murude;Aghayan, Iman;Kazemi, Mahdi
    • Structural Engineering and Mechanics
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    • v.48 no.2
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    • pp.207-220
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    • 2013
  • In this study, the vulnerability of two existing asymmetric steel building frames to Progressive Collapse (PC) is assessed. The buildings have different frame systems, steel sections and number of stories (nine and six). An alternate path method (APM) with a linear static analysis (LS) is carried out according to General Services Administration (GSA) 2003 guidelines. The Demand Capacity Ratio (DCR) of each primary element (beams and columns) is given with its specific details for all frames. The results show that the nine-story building with a dual frame system (moment frame with bracing system) has a lower susceptibility and greater resistance to PC than the six-story building with a simple building frame system (gravity system with bracing system). Implementing built-up box-shaped sections for columns is a better choice than using built-up I-shaped sections because there is no weak axis for the box section.

Adsorption of Ammonia on the Sulfuric Acid Treated ACF

  • Kim, K.H.;Shin, C.S.
    • Carbon letters
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    • v.2 no.2
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    • pp.109-112
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    • 2001
  • For the adsorption of ammonia, activated carbon fibers (ACFs) were subjected to sulfuric acid treatment in order to modify the surface functional groups. The surface acid and base value of ACFs were measured using titration and FT-IR spectrometry. SEM was used to investigate the surface morphology. Acid treatments by $H_3PO_4$, $H_2SO_4$, and $HNO_3$ were performed to increase the adsorption capacity of $NH_3$. As a result, Cellulose-based ACF has high adsorption capacity for ammonia. The ammonia removal efficiency of ACF was the maximum which was treated by 15 wt% sulfuric acid at $100^{\circ}C$ for 60 min. The average pore diameter little increased from $19{\AA}$ to $20.8{\AA}$ and the specific surface area of ACF considerably decreased and acid values increased by 15 wt% sulfuric acid treatment. Ammonia reacted with sulfonyl radicals. After adsorption of ammonia, white material was grown on the surface of ACF through the adsorption of ammonia and it was determined to ammonium sulfate.

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Study on electrochemical performances of sulfur-containing graphene nanosheets electrodes for lithium-sulfur cells

  • Son, Ki-Soo;Kim, Seok
    • Carbon letters
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    • v.15 no.2
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    • pp.113-116
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    • 2014
  • Due to their morphology, electrochemical stability, and function as a conducting carbon matrix, graphene nanosheets (GNS) have been studied for their potential roles in improving the performance of sulfur cathodes. In this study, a GNS/sulfur (GNS/S) composite was prepared using the infiltration method with organic solvent. The structure, morphology and crystallinity of the composites were examined using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The electrochemical properties were also characterized using cyclic voltammetry (CV). The CV data revealed that the GNS/S composites exhibited enhanced specific-current density and ~10% higher capacity, in comparison with the S-containing, activated-carbon samples. The composite electrode also showed better cycling performance for multiple charge/discharge cycles. The improvement in the capacity and cycling stability of the GNS/S composite electrode is probably related to the fact that the graphene in the composite improves conductivity and that the graphene is well dispersed in the composites.

A Comprehensive Study on the Effect Relationship among Core Competencies and Business Performance (기업의 핵심역량 영향관계 및 경영성과에 미치는 영향에 관한 포괄적 연구)

  • Lee, Hoeseon;Lee, Jong-Seok
    • Korean Management Science Review
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    • v.34 no.2
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    • pp.35-56
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    • 2017
  • Technology innovations have been accelerating changes across industries and intensifying competition. Enterprises are therefore required to continuously secure their internal and external competitiveness. Based on the principle that core competencies of a firm are essential to its competitiveness, many research studies have been conducted to figure out the effect of core competencies to business performance. However, individual research works considered a part of core competencies or limited to a specific industry, which means that their findings may differ when additional core competencies are included in their analysis. After re-establishing the definition of each core competency from literature review, this study comprehensively investigated the effect relationship among core competencies and business performance. Structural equation modeling and multiple regression analysis with 421 survey respondents from various industries were conducted for our empirical study.

Functional Properties of Modified Soybean Protein Isolate by Dimethylglutarylation (Dimethylglutarylation에 의한 변형대두단백질의 기능적 특성)

  • Choi, One-Kyun;Jung, Chul-Won
    • Journal of the Korean Society of Food Culture
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    • v.14 no.5
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    • pp.477-485
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    • 1999
  • This study was conducted to improve the functional properties of soybean protein isolate by dimethylglutarylation and acetylation. Amino acid composition and solubility of modified soybean protein by dimethylglutarylation were not changed, but lysine and trypsin inhibitor activity was decreased an isoelectric point was moved from pH5 to pH4 as a result of modification. Emulsification capacity and stability, foaming capacity and thermal stability were increased by the modification. In that 91% dimethylglutarylated protein did not coagulate when heating at $100^{\circ}C$ for 20 min. while its foaming stability was decreased. Whereas specific gravity was decreased by the modification of the soybean protein, relative viscosity and whiteness were improved. Generally, dimethylglutarylation produced more conformational changes in protein system than did in acetylation.

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Evaluation of Physical Properties and Adsorption Capacity of Regeneration GAC (재생 활성탄의 물성 및 흡착능 평가)

  • Mun, Ji-Young;Chae, Seon-Ha;Wang, Chang-Keun
    • Journal of Korean Society of Water and Wastewater
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    • v.23 no.4
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    • pp.407-416
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    • 2009
  • The objective of this study was to evaluate the variation of physical properties and adsorption capacity after regeneration of Granular Activated Carbon (GAC). It was found that the loss rate of regenerated carbon was related to the usage time of GAC. The correlations between iodide number and loss rate also determined. Effective size and uniformity coefficient for regenerated GAC were within a similar range compared to virgin GAC. This result indicated that the function as media is recovered. Although iodide number and specific surface area for regenerated GAC were not completely recovered compared to that of virgin GAC, cumulative pore volumes of regenerated GAC were increased. Removal efficiency of organic matter in regenerated GAC was resulted the same or slightly higher than that of virgin GAC. This result indicates that the number of mesopore responsible for removal of organic matter was increased after regeneration.

Application of High Damping Alloys for Vibration Reduction in Bridge Expansion Joints (Fe-Mn 제진합금을 적용한 교량용 신축이음장치의 진동저감 효과에 관한 연구)

  • Kim, T.H.;Baik, J.H.;Han, D.W.;Kim, J.C.;Baik, S.H.;Yoo, M.S.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.1019-1023
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    • 2006
  • Conventional methods for reducing vibration in engineering designs may be undesirable in conditions where size or weight must be minimized, or where complex vibration spectra exist. Fe-Mn Damping alloy with a combination of high damping capacity and good mechanical properties can provide attractive technical and economical solutions to problems involving seismic, shock and vibration isolation. We have studied the noise and vibration characteristic of Dampalloy and checked Dampalloy reduced noise about 3.9dB and vibration about 15.9 times as compared conventional material through laboratory research. With this result, we obtained a good possibility of material substitution about the bridge expansion joint

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Sharing Innovation's Benefits

  • Oh, Deog-Seong;Phillips, Fred
    • World Technopolis Review
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    • v.4 no.3
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    • pp.126-131
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    • 2015
  • WTR articles to date have addressed raising innovation capacity in lagging regions. We now move to the question of sharing the benefits of specific innovations, noting that one way to do this is to focus on a particular technology as a demonstration project within a capacity-building project. The word "sharing" implies mechanisms that go beyond simple buy-sell transactions. This paper catalogs a number of these mechanisms, which in fact include many well-known technology transfer techniques. The paper focuses in particular on two mechanisms, technology assessment and new institutions, the latter including three Korean institutions. A manager seeking to benefit from the several mechanisms currently must find them in as many different places. We therefore present the possible "roll-up" of sharing mechanisms as an opportunity in social entrepreneurship. We hope the paper will lead to an expanded list of sharing mechanisms, consideration of their feasibility in different regions, and ultimately a one-stop shop for managers seeking to benefit their own and other organizations by the sharing of innovations.