• Title/Summary/Keyword: HI

Search Result 4,737, Processing Time 0.038 seconds

The Characteristics of HI Decomposition using Pt/Al2O3 Catalyst Heat Treated in Air and Hydrogen Atmosphere (공기 및 수소 분위기에서 열처리 된 Pt/Al2O3 촉매의 HI분해반응 특성)

  • Park, Eun Jung;Ko, Yun Ki;Park, Chu Sik;Kim, Chang Hee;Kang, Kyoung Soo;Cho, Won Chul;Jeong, Seong Uk;Bae, Ki Kwang;Kim, Young Ho
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.25 no.3
    • /
    • pp.219-226
    • /
    • 2014
  • In HI decomposition, $Pt/Al_2O_3$ has been studied by several researchers. However, after HI decomposition, it could be seen that metal dispersion of $Pt/Al_2O_3$ was greatly decreased. This reason was expected of platinum loss and sintering, which platinum was aggregated. Also, this decrease of metal dispersion caused catalytic deactivation. This study was conducted to find the condition to minimize platinum sintering and loss. In particular, heat treatment atmosphere and temperature were examined to improve the activity of HI decomposition reaction. First of all, although $Pt/Al_2O_3$ treated in hydrogen atmosphere had low platinum dispersion between 13 and 18%, it was shown to suitable platinum form that played an important role in improving HI decomposition reaction. Oxygen in the air atmosphere made $Pt/Al_2O_3$ have high platinum dispersion even 61.52% at $500^{\circ}C$. Therefore, in order to get high platinum dispersion and suitable platinum form in HI decomposition reaction, air heat treatment at $500^{\circ}C$ was needed to add before hydrogen heat treatment. In case of 5A3H, it had 51.13% platinum dispersion and improved HI decomposition reaction activity. Also, after HI decomposition reaction it had considerable platinum dispersion of 23.89%.

OBU and System Development for HiPassPlusCard Nation-Wide Interoperable Transportation Card (하이패스플러스카드 전국호환 교통카드용 OBU 및 시스템 개발)

  • Jee, Dong-Mok;Lee, Ki-Han;Kim, Hye-Hyeon;Kim, Tae-Hee;Maeng, Jae-Hwan;Park, Ha-Na
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.9 no.4
    • /
    • pp.90-101
    • /
    • 2010
  • The existing HiPassPlusCard system is composed of the HiPassPlusCard, a Purchase SAM, a Purchase terminal, a settlement system and OBU. However, this system is confronted by the problem with its incompatibility. This problem occurred because the technology companies made cards in their own ways in respect of the parts which were not yet set by KS standard. Thus if existing HiPassPlusCard user wants to use any other public transportations, user would have to buy other cards and have to bring all them. Also if the HiPlusCard wants to extend their business to apply its technology into infrastructure of the other companies, the HiPlusCard has to construct infra independently so that it causes the such problems of duplicated investment. To solve these problems, we have analyzed and upgraded the existing HiPassPlusCard system, and we designed and developed the Nation-wide Interoperable HiPassPlusCard system. Then the conformity test demonstrated that it is efficiency-oriented and technically performs well. Also we, the HiPlusCard, the Korea Financial Telecommunications & Clearings and the KORAIL NETWORKS, run the Test-bed in Gwangju for 6 months. The test-bed indicated that Nation-wide Interoperable HiPassCard system practically works well.

Hypoxia-inducible factor: role in cell survival in superoxide dismutase overexpressing mice after neonatal hypoxia-ischemia

  • Jeon, Ga Won;Sheldon, R. Ann;Ferriero, Donna M.
    • Clinical and Experimental Pediatrics
    • /
    • v.62 no.12
    • /
    • pp.444-449
    • /
    • 2019
  • Background: Sixty percent of infants with severe neonatal hypoxic-ischemic encephalopathy die, while most survivors have permanent disabilities. Treatment for neonatal hypoxic-ischemic encephalopathy is limited to therapeutic hypothermia, but it does not offer complete protection. Here, we investigated whether hypoxia-inducible factor (HIF) promotes cell survival and suggested neuroprotective strategies. Purpose: HIF-1α deficient mice have increased brain injury after neonatal hypoxia-ischemia (HI), and the role of HIF-2α in HI is not well characterized. Copper-zinc superoxide dismutase (SOD)1 overexpression is not beneficial in neonatal HI. The expression of HIF-1α and HIF-2α was measured in SOD1 overexpressing mice and compared to wild-type littermates to see if alteration in expression explains this lack of benefit. Methods: On postnatal day 9, C57Bl/6 mice were subjected to HI, and protein expression was measured by western blotting in the ipsilateral cortex of wild-type and SOD1 overexpressing mice to quantify HIF-1α and HIF-2α. Spectrin expression was also measured to characterize the mechanism of cell death. Results: HIF-1α protein expression did not significantly change after HI injury in the SOD1 overexpressing or wild-type mouse cortex. However, HIF-2α protein expression increased 30 minutes after HI injury in the wild-type and SOD1 overexpressing mouse cortex and decreased to baseline value at 24 hours after HI injury. Spectrin 145/150 expression did not significantly change after HI injury in the SOD1 overexpressing or wild-type mouse cortex. However, spectrin 120 expression increased in both wild-type and SOD1 overexpressing mouse at 4 hours after HI, which decreased by 24 hours, indicating a greater role of apoptotic cell death. Conclusion: HIF-1α and HIF-2α may promote cell survival in neonatal HI in a cell-specific and regional fashion. Our findings suggest that early HIF-2α upregulation precedes apoptotic cell death and limits necrotic cell death. However, the influence of SOD was not clarified; it remains an intriguing factor in neonatal HI.

The Effect of SO2-O2 Mixture Gas on Phase Separation Composition of Bunsen Reaction with HIx solution (HIx 용액을 이용한 분젠 반응에서 상 분리 조성에 미치는 SO2-O2 혼합물 기체의 영향)

  • Han, Sangjin;Kim, Hyosub;Ahn, Byungtae;Kim, Youngho;Park, Chusik;Bae, Kikwang;Lee, Jonggyu
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.23 no.5
    • /
    • pp.421-428
    • /
    • 2012
  • The Sulfur-Iodine (SI) thermochemical hydrogen production process is one of the most promising thermochemical water splitting technologies. In the integrated operation of the SI process, the $O_2$ produced from a $H_2SO_4$ decomposition section could be supplied directly to the Bunsen reaction section without preliminary separation. A $HI_x$ ($I_2+HI+H_2O$) solution could be also provided as the reactants in a Bunsen reaction section, since the sole separation of $I_2$ in a $HI_x$ solution recycled from a HI decomposition section was very difficult. Therefore, the Bunsen reaction using $SO_2-O_2$ mixture gases in the presence of the $HI_x$ solution was carried out to identify the effect of $O_2$. The amount of $I_2$ unreacted under the feed of $SO_2-O_2$ mixture gases was little higher than that under the feed of $SO_2$ gas only, and the amount of HI produced was relatively decreased. The $O_2$ in $SO_2-O_2$ mixture gases also played a role to decrease the amount of a impurity in $HI_x$ phase by only striping effect, while that in $H_2SO_4$ phase was hardly affected.

Localization of the Membrane Interaction Sites of Pal-like Protein, HI0381 of Haemophilus influenzae

  • Kang, Su-Jin;Park, Sung Jean;Lee, Bong-Jin
    • Molecules and Cells
    • /
    • v.26 no.2
    • /
    • pp.206-211
    • /
    • 2008
  • HI0381 of Haemophilus influenzae was investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. HI0381 is a 153-residue peptidoglycan-associated outer membrane lipoprotein, and a part of the larger Tol/Pal network. Here, we report its backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments, and secondary structure predictions. About 97% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances covering 131 non-proline residues of the 134 residue, mature protein, were clarified by sequential and specific assignments. CSI and TALOS analyses revealed that HI0381 contains five ${\alpha}$-helices and five ${\beta}$-strands. To characterize the structure of HI0381, the effects of pH and salt concentration were investigated by CD. In addition, the structural changes occurring when HI0381 was in a membranous environment were investigated by comparing its HSQC spectra and CD data in buffer and in DPC micelles; the results showed that helix ${\alpha}4$ and strand ${\beta}4$ became aligned with the membrane. We conclude that the conformation of HI0381 is affected by the membrane environment, implying that its folded state is directly related to its function.

A Logical Critique of Criticism and Anticriticism of Lee Yeung-Hi (리영희 비판과 반비판의 논리적 비판: '북한맹.시장맹' 논쟁을 중심으로)

  • Shon, Seok-Choon
    • Korean journal of communication and information
    • /
    • v.61
    • /
    • pp.118-133
    • /
    • 2013
  • Lee Yeung-Hi is one of the most influential journalist in the modern history of Korea. Nevertheless, the judgement about him has been parallelized by opposite sides. He is called 'the Master of ideology', while the other calls him 'the culprit of theorization'. This thesis deduced the contemporary meaning of person Lee Yeung-Hi in order to promote communication for both sides. I compared their logical arguments and pointed out the error they missed. Also, I clarified that the criticism and anticriticism for Lee Young-Hi in the fields of both journalism and academia have fallacies, such as the fallacy of straw man, and the fallacy of question-begging. I criticized their arguments through the view of 'struggling to seek truth', which is the core value of Lee Yeung-Hi's thought. The necessity of communication between advocators and it's critics is due to the condition of Korean Journalism. Korean Journalism does not have much space to accept Lee Young-Hi in only one side. Paradoxically, the contemporary meaning of the truth that Journalist Lee Young-Hi had sought is profound and deep because of the condition where Korean Journalism is being dominated by political parallelism.

  • PDF

A Study on the Method of Highway Hi-pass Lane Arrangement and Operation (고속도로 영업소 하이패스 차로배치 및 운영에 관한 연구)

  • Lee, Soo Beom;Lim, Joon Beom;Joo, Sung Kab
    • Journal of Korean Society of Transportation
    • /
    • v.31 no.6
    • /
    • pp.22-33
    • /
    • 2013
  • Currently average daily traffic using Hi-pass has increased over 3 times that of 2008 and more than half of highway traffic now uses High-pass. At this juncture, reassessment on the overall operation of Hi-pass is required to improve the safety aspect of toll booths and the flow of traffic. Although existing Hi-pass operation manual presents the methods of alignment, they do not reflect actual forms of vehicles and do not properly take the safety of toll booth and flow of the traffic into consideration. In order to compensate these problems, this study classifies highway tollbooths into two categories of mainline type and interchange type, and establishes the standard of lane alignment by traffic conflict analysis based on the types divided according to geometric structure or environment around the tollbooths. In addition, traffic flows around the tollbooths were reflected with the stage to arrange Hi-pass lanes according to the volume of traffic on the lanes for Hi-pass.

Structural Design and Analysis of a 6U Nano-Satellite HiREV (6U급 초소형위성 HiREV의 구조 설계 및 해석)

  • Shin, Han-Seop;Kim, Hae-Dong
    • Journal of Aerospace System Engineering
    • /
    • v.12 no.3
    • /
    • pp.26-37
    • /
    • 2018
  • The Korea Aerospace Research Institute has developed a 6U HiREV Nano-satellite for the observation of the earth using high resolution videos and images. Since the 6U Nano-satellite is bulky compared to the 1U/3U Nano-satellite, the first natural frequency is relatively low. Large equivalent stress and total deformation, due to structural load, can be generated. In this paper, the design of the 6U HiREV Nano-satellite is described and structure analysis, such as acceleration load analysis, modal analysis, and random vibration analysis are carried out. It is proven that the structural design of the 6U HiREV is stable. These results will be useful as reference materials for the development of additional 6U Nano-satellites, which will be applied to various future missions in KOREA.

Characteristics of Hydrogen Iodide Decomposition using Alumina-Supported Ni Based Catalyst (Ni 기반 촉매를 이용한 HI 분해 반응 특성)

  • KIM, JI HYE;PARK, CHU SIK;KIM, CHANG HEE;KANG, KYOUNG SOO;JEONG, SEONG UK;CHO, WON CHUL;KIM, YOUNG HO;BAE, KI KWANG
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.26 no.6
    • /
    • pp.507-515
    • /
    • 2015
  • HI decomposition reaction requires a catalyst for the efficient production of hydrogen as a key reaction for hydrogen production in sulfur-iodine thermochemical water-splitting (SI) cycle. As a catalyst used in the reaction, the performance of platinum catalyst is excellent. While, the platinum catalyst is not economical. Therefore, studies of a nickel catalyst that could replace platinum have been carried out. In this study, the characteristics of the catalytic HI decomposition on the amount of loaded nickel (Ni = 0.1, 0.5, 1, 3, 5, 10 wt%) were investigated. As the supported Ni amount increased up to 3 wt%, HI decomposition was found to increase in linear proportion. However, the conversion of $Ni/Al_2O_3$ catalyst loaded above 3 wt% was not linear. It was thought that the different HI decomposition characteristics was caused in the size and metal dispersion of Ni particles of catalyst. The physical property of catalyst before and after HI decomposition reaction was characterized by BET, chemisorption, XRD and SEM analysis.

Alteration of Recognition Sequence by Restriction Endonuclease -Effect of pH and Hydrophobicity on BamHI- (제한효소의 인식자리 변화 -BamHI 특이성에 미치는 산도와 소수성의 영향-)

  • 이강민
    • KSBB Journal
    • /
    • v.11 no.2
    • /
    • pp.193-200
    • /
    • 1996
  • In molecular biology, type-II restriction endonuclease, which specifically recognize and cleave DNA at a limited number of sites, have been exploited as a means of characterizing DNA fragments, DNA mapping for genetic engineering. Type-II restriction endonucleases have been found to modulate their substrate specificity under modified conditions such as extreme pH, ionic strength, high enzyme concentration, substitution of metallic cofactors or addition of organic solvents. This study was initiated to investigate the modification of recognition specificity of BamHI according to the different pH and organic solvent under the given buffer condition. The specificity of BamHI is highly depends on the presence of hydrophobicity (LogP: partition coefficient) and pH of reaction solution. The specificity of BamHI is changed in range of LogP -1.03∼-1.35(at pH 7.5), -1.03∼-2.5 (at pH 8.0), -0.75∼-0.25(at pH 8.5), 0.32∼-2.5(at pH 8.9), respectively. Alteration of specificity appears in lower concentration of organic solvent when the reaction occurs in more alkali pH. For example, in DMSO solution, alteration of specificity appears in 20% concentration at pH 7.5 but in 4% concentration at pH 8.9.

  • PDF