R&D Status of High-current Accelerators at IFP

J. J. Deng,J. S. Shi,W. P. Xie,L. W. Zhang,K. Z. Zhang,S. P. Feng,J. Li,M. Wang,Y. He,L. S. Xia,Z. Y. Dai,H. T. Li,L. Wen,S. F. Chen,X. Li,Q. G. Lai,M. H. Xia,Y. C. Guan,S. Y. Song,L. Chen 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.61

High-current accelerators have many important applications in Z-pinches, high-power microwaves, and free electron lasers, imploding liners and radiography and so on. Research activities on Zpinches, imploding liners, radiography at the Institute of Fluid Physics (IFP) are introduced. Several main high-current accelerators developed and being developed at IFP are described, such as the Linear Induction Accelerator X-Ray Facility Upgrade (LIAXFU, 12 MeV, 2.5 kA, 90 ns), the Dragon-I linear induction accelerator (20 MeV, 2.5 kA, 60 ns), and the Primary Test Stand for Z-pinch (PTS, 10 MA, 120 ns). The design of Dragon-II linear induction accelerator (20 MeV, 2.5 kA, 3 × 60 ns) to be built will be presented briefly.

Electrolyte effect on the catalytic performance of Ni-based catalysts for direct internal reforming molten carbonate fuel cell

Li, Z.,Devianto, H.,Yoon, S.P.,Han, J.,Lim, T.H.,Lee, H.I. Pergamon Press ; Elsevier Science Ltd 2010 International journal of hydrogen energy Vol.35 No.23

An active and tolerant Ni-based catalyst for methane steam reforming in direct internal reforming molten carbonate fuel cells (DIR-MCFCs) was developed. Deactivation of reforming catalysts by alkali metals from the electrolyte composed of Li<SUB>2</SUB>CO<SUB>3</SUB> and K<SUB>2</SUB>CO<SUB>3</SUB> is one of the major obstacles to be overcome in commercialization of DIR-MCFCs. Newly developed Ni/MgSiO<SUB>3</SUB> and Ni/Mg<SUB>2</SUB>SiO<SUB>4</SUB> reforming catalysts show activities of ca. 80% methane conversion. Subsequent to electrolyte addition to the catalyst, however, the activity of Ni/Mg<SUB>2</SUB>SiO<SUB>4</SUB> decreases to ca. 50% of its initial value, whereas Ni/MgSiO<SUB>3</SUB> catalyst retains its initial activity. Results obtained from temperature-programmed reduction and X-ray photoelectron spectroscopy identify unreduced Ni<SUP>3+</SUP> as a decisive factor in keeping catalytic activity from the electrolyte.

Microstructural Stability and Creep Performance of a Novel Low-Cost Single Crystal Superalloy

Z. H. Tan,X. G. Wang,Y. L. Du,Y. M. Li,Y. H. Yang,J. L. Liu,J. D. Liu,J. G. Li,Y. Z. Zhou,X. F. Sun 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The increasing pursuit of advanced aero-engines with lower ratio between the cost and performance has greatly promotedthe demanding of single crystal superalloys characterized by low cost and outstanding temperature capability. In this study,a novel low-cost single crystal superalloy was designed and the creep tests as well as micro-characterization were carried outon the experimental alloy. The results illustrated that the novel single crystal alloy exhibited an ideal microstructural stabilitywithout precipitating TCP phases, after long-term thermal exposure at the ultimate service temperature of third generationsingle crystal superalloys. Moreover, the experimental alloy with only 3 wt% Re addition demonstrated remarkable creepresistance and maintained a very low minimum creep rate at 1100 °C/137 MPa and 1120 °C/137 MPa, while the accumulationand coalescence of micro-pores had eventually led to the alloy fracture. Apart from that, the compact interfacial dislocationnetworks the 2nd γ′ phase were observed after high-temperature creep rupture, and the typical a < 010 > superdislocationswith relatively poor mobility was found at 1120 °C. At 760 °C/800 MPa, both the minimum creep velocity and entire creepstain was increased evidently, however, the ultimate creep rupture life of the alloy had still reached 200 h. The correspondingdeformation mechanism was identified as the combination of superdislocation pairs shearing and a/3 < 121 > partial dislocationcutting the γ′ phase with a SISF being generated. In general, the novel single crystal alloy characterized by remarkablemechanical properties and cost reduction possesses a great potential for future application in the advanced aircraft engines.

Protective effects of vitamins C and E on dichlorodiphenyltrichloroethane-induced genotoxicity and hepatotoxicity in human liver cells

Xiao Ting Jin,Li Song,Xiang Yuan Liu,Hang Qing Li,Long Cheng,Zhuo Yu Li1,,Z. Y. Li 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.2

Dichlorodiphenoxytrichloroethane (DDT), a persistent organic pollutant and hepatotoxicant, is used to control the malaria. However, scarce information exists on relevant effective inhibitors of DDT’ toxicity. The aim of this study was to investigate protective effects of natural antioxidants vitamin C (VC) or/and vitamin E (VE) on p,pʹ-DDT-induced genotoxicity and hepatotoxicity in human liver cells. p,pʹ-DDT exposure increased levels of chromatin condensation, comet parameter, micronucleus induction and DPC coefficient of HL-7702 cells in a dose-dependent manner. Also, an increase in mRNA levels of CYP1A1 as well as CYP3A4, and a decrease in UGT along with GST were observed. Interestingly, supplementation with VC or/and VE prevented p,pʹ-DDT-caused alterations in DNA damage and phase metabolism gene expressions, and the combination of VC and VE had a more protective effect than VC or VE alone. These findings illustrated that VC or/and VE could be beneficial for the alleviation of p,pʹ-DDT-incurred toxicity in human liver cells.

Pressure and temperature dependence of the decomposition pathway of LiBH₄

Yan, Yigang,Remhof, Arndt,Hwang, Son-Jong,Li, Hai-Wen,Mauron, Philippe,Orimo, Shin-ichi,Zü,ttel, Andreas The Royal Society of Chemistry 2012 Physical chemistry chemical physics Vol.14 No.18

<P>The decomposition pathway is crucial for the applicability of LiBH<SUB>4</SUB> as a hydrogen storage material. We discuss and compare the different decomposition pathways of LiBH<SUB>4</SUB> according to the thermodynamic parameters and show the experimental ways to realize them. Two pathways, <I>i.e.</I> the direct decomposition into boron and the decomposition <I>via</I> Li<SUB>2</SUB>B<SUB>12</SUB>H<SUB>12</SUB>, were realized under appropriate conditions, respectively. By applying a H<SUB>2</SUB> pressure of 50 bar at 873 K or 10 bar at 700 K, LiBH<SUB>4</SUB> is forced to decompose into Li<SUB>2</SUB>B<SUB>12</SUB>H<SUB>12</SUB>. In a lower pressure range of 0.1 to 10 bar at 873 K and 800 K, the concurrence of both decomposition pathways is observed. Raman spectroscopy and <SUP>11</SUP>B MAS NMR measurements confirm the formation of an intermediate Li<SUB>2</SUB>B<SUB>12</SUB>H<SUB>12</SUB> phase (mostly Li<SUB>2</SUB>B<SUB>12</SUB>H<SUB>12</SUB> adducts, such as dimers or trimers) and amorphous boron.</P> <P>Graphic Abstract</P><P>The thermodynamic properties of LiBH<SUB>4</SUB> and its possible decomposition products and intermediates allow flexibility in selection of the decomposition pathway by tuning the external parameters such as pressure and temperature. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cp40131b'> </P>

Characteristics of alkali-resistant Ni/MgAl₂O₄ catalyst for direct internal reforming molten carbonate fuel cell

Park, D.S.,Li, Z.,Devianto, H.,Lee, H.I. Pergamon Press ; Elsevier Science Ltd 2010 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY - Vol.35 No.11

Direct internal reforming - molten carbonate fuel cell (DIR-MCFC) has advantages of higher efficiency and smaller size. However, deactivation of the catalyst by alkali carbonate electrolytes poses a significant problem in MCFC. To solve this problem, Ni/MgO and Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> catalysts were compulsively mixed with a eutectic mixture of Li<SUB>2</SUB>CO<SUB>3</SUB> and Na<SUB>2</SUB>CO<SUB>3</SUB> prior to a methane steam reforming activity test. Activity of Ni/MgO rapidly decreased, while that of Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> remained steady due to good alkali resistance. To analyze the effects of alkali addition, N<SUB>2</SUB> adsorption-desorption, X-ray diffraction, temperature-programmed reduction and oxidation, scanning electron microscopy, and X-ray photoelectron spectroscopy experiments were carried out. Both Ni/MgO and Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> showed sintering of Ni and blocking of pores, which reduced the catalytic activity. However, Ni/MgAl<SUB>2</SUB>O<SUB>4</SUB> showed other positive effects such as stronger metal-support interaction and increased dissociative adsorption.

수험생활 중 경주 및 포항 지진 경험

김선주,김유영,김은주,박솔민,배지윤,이민영,이유진,정재원,Li Keying,Wuyingjinzhu,신수진,도지영 이화여자대학교 간호과학대학 2019 이화간호학회지 Vol.- No.53

Purpose: The purpose of this study was to understand the experiences of Gyeongju and Pohang earthquakes during the examinees’ life. Methods: This study applied Colaizzis’s Phenomenological method. The Data was collected through in-depth interviews with a total 8 students of university in Seoul. Results: On the analysis of the interviews, their experience can be expressed as ‘Feeling embarrassed and frightened by earthquakes’, ‘Reduced susceptibility to earthquake hazards due to heavy exam pressure’, ‘Increased exam stress due to earthquake’, ‘Feeling the inadequacy of examinees' earthquake related safety measures in retrospect’. Conclusion: This study was meaningful in deeply understanding of their experiences and revealing that the examinees were more focused on studying rather than actively coping with the disaster. Furthermore, it reconsider the social climate surrounding college admission exams. This study meaningfully discovered that examinees could not stably prepare for both the exam and the earthquake evacuation procedures due to the timing of the earthquake in relation to their upcoming college admission test. Therefore, this study highlighted the examinees’ difficulties due to the earthquakes and increased the necessity of acute phase nursing intervention in relation to the seismic safety education system.

재래 흑돼지와 중국 재래돈간의 Melanocortin Receptor 1(MC1R) 유전자의 유전자형 분석

이성수,양보석,정진관,고서봉,오성종,양영훈,김규일,이찬동,풍서당 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.1

PCR-RFLP analysis of Melanocortin receptor 1 (MC1R) gene was carried out to investigate the genotype distribution in Korean-Native and Chinese-Native pig breeds(Neijiang, Putian, Wannanhua and Jinhua). Allelic variants of MC1R in pigs were analyzed by digestion of BspH I , AccII and Hha I . Ncijiang. Wannanhua and Jinhua had only MC1R*2 allele which is considered to be typical genotype for Meishan and Large Black. Among 20 Korean-Native Pigs and 5 Putian pigs, 10 and 2 heads had the MC1R*3 allele (*2/3 or 3/3), respectively, which was detected in European pig breeds such as Hampshire, Large White, and Pietrain. The remaining animals possessed the genotype MC1R*2/2, probably reflecting the genetic introgression of MC1R*3 allele into Korean-Native and Putian pig breeds by the crossbreeding for improvement. The alleles MC1R*l and MC1R*4, which are considered to be typical allele for European Wild Boar with wild-type coat color and Duroc with red coat color, respectively, were not detected in pig breeds used in this experiment. These results indicate that the analysis of genotype frequencies of MC1R gene may be a useful tool for the conservation of Korean-Native and Chinese-Native pig breeds.

The effect of spin reorientation transition of antiferromagnetic NiO on the Py magnetic anisotropy in Py/NiO/CoO/MgO(0 0 1)

Yang, M.,Li, Q.,N'Diaye, A.T.,Dong, Q.Y.,Gao, N.,Arenholz, E.,Hwang, C.,Wu, Y.Z.,Qiu, Z.Q. Elsevier 2018 Journal of magnetism and magnetic materials Vol.460 No.-

<P><B>Abstract</B></P> <P>Using X-ray Magnetic Linear Dichroism (XMLD) measurement, we investigate the antiferromagnetic (AFM) NiO spin reorientation transition (SRT) in epitaxial NiO/CoO/MgO(0 0 1) system at room temperature and constructed a complete NiO spin phase diagram. Then utilizing Magneto-Optic Kerr Effect (MOKE) combined with a rotation magnetic field (ROTMOKE), we investigated the effect of NiO SRT on the magnetic anisotropy of a ferromagnetic (FM) Py overlayer in Py/NiO/CoO/MgO(0 0 1) system. We find that the Py coercivity and anisotropy only slightly enhanced for Py on top of out-of-plane NiO spins but greatly enhanced for Py on top of in-plane NiO spins. Both the uniaxial and fourfold anisotropies of the Py showed a clear dependence on the NiO spin orientation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Spin reorientation transition (SRT) of antiferromagnetic NiO. </LI> <LI> Direct measurement of antiferromagnetic spins using XMLD. </LI> <LI> Quantitative determination of Py magnetic anisotropy using ROTMOKE. </LI> <LI> Demonstration of the effect of the NiO SRT on the Py magnetic anisotropy. </LI> </UL> </P>

STUDY OF CUTTING AERIAL PMMA WITH MINIATURE DETONATION CORD

Z.Q. LI,L.M. ZHAO,Y.G. ZHAO 한국소성가공학회 2008 한국소성가공학회 컨퍼런스 Vol.2008 No.10