• Title/Summary/Keyword: barely

Search Result 468, Processing Time 0.037 seconds

Thermal Oxidative Purification of Detonation Nanodiamond in a Gas-Solid Fluidized Bed Reactor

  • Lee, Jae Hoon;Youn, Yong Suk;Lee, Dong Hyun
    • Korean Chemical Engineering Research
    • /
    • v.56 no.5
    • /
    • pp.738-751
    • /
    • 2018
  • The effect of the reaction temperature and reaction time on the thermal oxidative purification quality of detonation nanodiamond (NDsoot) was investigated in a gas-solid fluidized bed reactor of a $0.10m-ID{\times}1.0m$-high stainless steel column with zirconia beads ($d_{SV}=99.2{\mu}m$). The carbon conversion increased with increasing the reaction temperature; however, when the reaction temperature was greater than 773 K, the carbon conversion did not increase. The content of $sp^3$-hybridized carbon at the reaction temperature of 703 K barely changed when the reaction time was more than 30 minutes, but at 773 K, the content decreased as preferred. At 703 K, the purification quality increased with the increasing reaction time; however, at 773 K, the purification quality increased up to 30 minutes and then decreased rapidly.

Derivation of Factors for Improvement for Efficient Procurement and Lifting Management of Modular Construction (모듈러 건축공사의 조달 및 양중 효율화를 위한 중점개선 요구사항 도출)

  • Kim, Min Ju;Lee, Dongmin;Lim, Hyunsu;Cho, Hunhee;Kang, Kyung-In
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2015.05a
    • /
    • pp.211-212
    • /
    • 2015
  • Procurement and lifting scheduling of modules and resources in modular construction, where modules that are manufactured from factory are delivered and assembled on site, is a crucial factor that determines the efficiency of the whole construction. However, previous studies have barely acknowledged the significance of resource procurement process and lifting of modules in modular construction. Therefore, this research aims to derive factors that are in need of improvement for successful implementation of procurement and lifting efficiency, and visualize them according to their importance and performance on improvement through IPA(Important Performance Analysis).

  • PDF

Effect of Acetophenone on the Rate of Wool Dyeing (아세토페논이 양모의 염색속도에 미치는 영향)

  • Dho, Seong-Kook
    • Fashion & Textile Research Journal
    • /
    • v.10 no.3
    • /
    • pp.394-398
    • /
    • 2008
  • One of barely water soluble ketones, acetophenone (AP) was dissolved in methanol and then was mixed with aqueous solution of C. I. Red Acid 114. In order to find out the role of AP in the dyeing process the rate constants and the activation parameters were calculated. The rate for the dyeing with AP was faster than that without it. Because of the reduced temperature dependence by AP the activation energy ($E_a$) for the dyeing with AP was smaller than that without it. With increasing temperature the activation enthalpy (${\Delta}H^*$), the activation entropy (${\Delta}S^*$), and the activation free energy ($G^*$) decreased, which was more noticeable in dyeing with AP. The rate constants and the activation parameters agreed well with the results from the previous reports that the ability of AP to increase disaggregation of dye molecules, loosening the wool fiber, and wickabilty of dyeing solution made it possible to dye wool fiber at low temperature.

A Study on the Relationship between Sound Quality and Structural Mechanics in Automobiles (차량 구조 강성과 소음 음질간의 상관도 연구)

  • Choi Jongdae;Kim Sangmin
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • autumn
    • /
    • pp.239-242
    • /
    • 2000
  • In the present study, the influence of car body structures to the noise and vibration characteristics has been sought. The numerical modal analysis for the body-in-white is employed to predict the vibratory response of structure, and then followed by the experimental modal testing to confirm the validity of the model. Using the results of numerical simulations with the designated modal parameters, the optimal structural configuration has been deduced. Special interests have been paid to the sensitivity of sound quality to the structural integrity. Since the structural integrity has a close relationship to the structure-born noise, the substantially low frequency range, which is far below the frequency range almost barely sensible by human auditory organ but still quite influential to overall impression, is especially examined. The subjective assessment agrees with the objective evaluation by means of traditional sound measures as well as psychoacoustic metrics.

  • PDF

Gold Nanoparticle Optical Effect on Graphene (금 미세 입자에 의한 그래핀 광학 특성 변화)

  • Park, Byeongho;Lim, Juhwan;Jun, Seong Chan
    • Transactions of the Society of Information Storage Systems
    • /
    • v.9 no.1
    • /
    • pp.1-4
    • /
    • 2013
  • Graphene and Graphene oxide have intense interest in fields such as physics, chemistry, and materials science, among others. They are the promising material for solving the current limitation that organics have barely luminescence. We observed variation of photoluminescence on graphene oxide based solution with Gold nanoparticle. Gold nanoparticles lead to shift the peak wavelength of graphene oxide and to enhance the photoluminescence intensity totally. This shows the possibility that control the luminescence property of graphene oxide by adding gold nanoparticle.

Overcoming Negotiation Asymmetry in Transboundary Water Relations: The Rhine River Basin Case

  • Rho, Helen Hyun
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2015.05a
    • /
    • pp.230-230
    • /
    • 2015
  • When and why do states cooperate in international basins? In recent years, there have been increasing attempts to apply international relations theories such as realism and neo-liberal institutionalism in understanding prospect of cooperation among sovereign states over shared rivers. Realists of hydropolitics argue that fate of cooperation resides in hands of hegemons and distribution of aggregate power among riparian states. Such pessimistic contention has been challenged by neo-liberal institutionalists, especially through regime theory. However, regime theory barely explains why and how cooperation emerges in the first place prior to regime formation. Therefore, the research suggests the game theory from neo-liberal institutionalism as an alternative theoretic approach. The accountability of Oye (1986)'s theoretical framework is illustrated through the case of cooperation in the Rhine River Basin.

  • PDF

The Low-Radiation Dosimetry Application of "tris" Lyoluminescence using Electron Paramagnetic Resonance at Low Temperature

  • Son, Phil-Kook;Choi, Suk-Won;Kim, Sung-Soo;Gwag, Jin-Seog
    • Journal of Magnetics
    • /
    • v.17 no.3
    • /
    • pp.172-175
    • /
    • 2012
  • We present a method for detecting very weak radiation by analyzing the inner structure of irradiated tris (lyoluminescence) materials using electron paramagnetic resonance (EPR) at low temperature. Organic materials have been looked into for use in emergency dosimetry of inhabitants around radiation accidents. However, this technology has never been applied to imperceptible radiation doses (< 0.5 Gy) because there is no proper method for detecting the change of inner structure of the subject bombed by very weak radiation at room temperature. Our results show that tris materials can be applied as a radiation detectors of very small radiation doses below 0.05 Gray, if EPR is used at low temperature (130 K ${\leq}$ T ${\leq}$ 270 K). The EPR signal intensity from the irradiated-tris sample had barely faded at all after 1 year.

Study of Dark Matter at e+e- Collider using KISTI-5 Supercomputer

  • Park, Kihong;Cho, Kihyeon
    • International Journal of Contents
    • /
    • v.17 no.3
    • /
    • pp.67-73
    • /
    • 2021
  • Dark matter is barely known because it cannot be explained using the Standard Model. In addition, dark matter has not been detected yet. It is currently being explored through various ways. In this paper, we studied dark matter in an electron-positron collider using MadGraph5. The signal channel is e+e- → 𝜇+𝜇-A' where A' decays to dimuon. We studied the cross-section by increasing the center-of-mass energy. Central processing unit (CPU) time of simulation was compared with that using a local Linux machine and a KISTI-5 supercomputer (Knight Landing and Skylake). Furthermore, one or more cores were used for comparing CPU time among machines. Results of this study will enable the exploration of dark matter in electron-positron experiments. This study also serves as a reference for optimizing high-energy physics simulation toolkits.

Inhibition of glutathione S-transferase omega 1-catalyzed protein deglutathionylation suppresses adipocyte differentiation

  • Sana Iram;Areeba Mashaal;Seulgi Go;Jihoe Kim
    • BMB Reports
    • /
    • v.56 no.8
    • /
    • pp.457-462
    • /
    • 2023
  • Glutathione S-transferase omega 1 (GstO1) is closely associated with various human diseases, including obesity and diabetes, but its functional mechanism is not fully understood. In the present study, we found that the GstO1-specific inhibitor C1-27 effectively suppressed the adipocyte differentiation of 3T3-L1 preadipocytes. GstO1 expression was immediately upregulated upon the induction of adipocyte differentiation, and barely altered by C1-27. However, C1-27 significantly decreased the stability of GstO1. Moreover, GstO1 catalyzed the deglutathionylation of cellular proteins during the early phase of adipocyte differentiation, and C1-27 inhibited this activity. These results demonstrate that GstO1 is involved in adipocyte differentiation by catalyzing the deglutathionylation of proteins critical for the early phase of adipocyte differentiation.

Supermassive Black Hole Masses of ~500k QSOs from the Sloan Digital Sky Survey

  • Taak, Yoon Chan;Im, Myungshin
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.44 no.2
    • /
    • pp.77.2-77.2
    • /
    • 2019
  • Measurements of supermassive black hole (SMBH) masses are crucial in studying the co-evolution of SMBHs and their host galaxies. Although reverberation mapping is the most accurate method known to date, this requires spectroscopic monitoring over long periods. Thus, the current sample barely reaches three digits. The virial method, on the other hand, uses emission-line and continuum properties from a single spectrum to estimate the SMBH mass; hence the name single-epoch method. The Sloan Digital Sky Survey (SDSS) has observed spectra of almost all quasi-stellar objects (QSOs) discovered so far. Building on previous studies, using the single-epoch method, we estimate the SMBH masses of more than 500,000 QSOs from the SDSS DR14 Quasar Catalog. This increases the mass-estimated SMBH sample almost by a factor of two, and especially more for the low-mass regime, which was the main target of SDSS-IV (eBOSS).

  • PDF