• 제목/요약/키워드: ring protection

검색결과 94건 처리시간 0.024초

Enhanced bacterial resistance in transgenic tobacco expressing a BrRZFP1 encoding a C3HC4-type RING zinc finger protein from Brassica rapa

  • Jung, Yu Jin;Nou, Ill Sup;Hong, Sung Kee;Lee, Young Kee;Cho, Yong Gu;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
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    • 제40권1호
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    • pp.49-54
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    • 2013
  • C3HC4-type RING zinc finger proteins essential in the regulation of plant processes, including responses to abiotic stresses. We previously isolated and examined the C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under abiotic stresses. To elucidate the role of the BrRZFP1 transcription factor in gene regulation, we transformed tobacco plants with the BrRZFP1 gene. Plants were regenerated from 82 independently transformed callus lines of tobacco and analysed for transgene expression. Transgene integration and expression was confirmed by Southern and RT-PCR analyses, respectively. T2 plants displayed more tolerance to the bacterial pathogens Pectobacterium carotovorum and Ralstonia solanacearum, and the tolerance levels were correlated with BrRZFP1 expression levels. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and its overexpression in plants could increase biotic stress resistance.

Introduction of Heterocycles at the 2-Position of Indoline as Ester Bioisosteres

  • Lee, Sung-Kyung;Yi, Kyu-Yang;Yoo, Sung-Eun
    • Bulletin of the Korean Chemical Society
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    • 제25권2호
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    • pp.207-212
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    • 2004
  • In this study, we attempted to prepare compounds with heterocyclic replacements for metabolically unstable esters of benzopyranyl indole-2-carboxylic esters, which showed good in vitro and in vivo cardioprotective efficacies possibly through the opening of mitochondrial ATP-sensitive potassium channel ($K_{ATP}$). Initially, we tried to construct indolin-2-yl-heterocycles using unprotected indoline-2-carboxylic acid, but the cyclization was proceeded with oxidation of the indoline ring to the indole, which didn't react with benzopyranyl epoxide. Thus we introduced N-Boc group to deplete the electron density of the indoline ring. We successfully prepared various indolin-2-yl-heterocycles by the cyclization of the building blocks including carboxamide, ${\beta}$-hydroxy amide, hydrazide, nitrile starting from N-Boc-indoline-2-carboxylic acid.

YBCO 고온초전도링의 퀜치현상해석 (The analysis of quenching mechanism of a YBCO HTSC ring)

  • 주민석;이찬주;추용;고태국
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1996년도 하계학술대회 논문집 A
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    • pp.178-180
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    • 1996
  • An Inductive high-Tc superconducting fault current limiter using YBCO superconducting ring in the secondary part has many advantages in power networks. It is based on the appearance of resistivity in the superconductors and this paper is studied on the relation between the resistivity and the temperature of superconductors. In many other devices using superconductors, it is important to prohibit the superconductors from quenching for the protection of the whole system, or at least the superconductors.ᢁ

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발전용 발전기 여자설비의 오일 오염방지 (Prevention of Oil Contamination in the Excitation System of a Power Plant Generator)

  • 최재규;유호선;문승재
    • 플랜트 저널
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    • 제7권2호
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    • pp.30-38
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    • 2011
  • The purpose of this paper is to review the understanding of pollution causes in the excitation system and how to solve the problem. The cause of the problem was in-leakage of bearing lubricant oil through the gap between rotor and outer in the air deflector, which was triggered by a negative pressure with respect to the operation of a collector ring fan in the collector house. In order to prevent exciting current transmission equipment pollutant, the reduction of the negative gage pressure of the inside of collector house is required. The protection in-leakage of bearing lubricant oil through the gap between rotor and outer of the air deflector are necessary. The reduction of the inside diameter of air deflector and the expansion of inlet filter of collector house are inevitable.

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Anonymous Authentication Scheme based on NTRU for the Protection of Payment Information in NFC Mobile Environment

  • Park, Sung-Wook;Lee, Im-Yeong
    • Journal of Information Processing Systems
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    • 제9권3호
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    • pp.461-476
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    • 2013
  • Recently, smart devices for various services have been developed using converged telecommunications, and the markets for near field communication mobile services is expected to grow rapidly. In particular, the realization of mobile NFC payment services is expected to go commercial, and it is widely attracting attention both on a domestic and global level. However, this realization would increase privacy infringement, as personal information is extensively used in the NFC technology. One example of such privacy infringement would be the case of the Google wallet service. In this paper, we propose an zero-knowledge proof scheme and ring signature based on NTRU for protecting user information in NFC mobile payment systems without directly using private financial information of the user.

Thiadiazole Derivatives as Potential Anticonvulsant Agents

  • Mullick, Pooja;Khan, Suroor A.;Verma, Surajpal;Alam, Ozair
    • Bulletin of the Korean Chemical Society
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    • 제32권3호
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    • pp.1011-1016
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    • 2011
  • A series of thiadiazole derivatives were synthesized with differently substituted benzoic acids which were cyclized to give differently substituted thiazolidin-4-one. Elemental analysis, IR, $^1H$ NMR, $^{13}C$ NMR and mass spectral data confirmed the structure of the synthesized compounds. The derivatives of these moieties were evaluated for anticonvulsant activity by MES model and neurotoxicity by rotarod method. The synthesized compounds showed good potential for anticonvulsant activity besides this, the compounds also showed neurotoxic effect. It was observed that compounds with $OCH_3$ at 3, 4 position of phenyl ring [5(a-l)] showed less protection against convulsions as compared to compounds having unsubstituted phenyl ring [4(a-l)].

ANALYSIS OF SPATIAL AND TEMPORAL ADAPTIVE PROCESSING FOR GNSS INTERFERENCE MITIGATION

  • Chang, Chung-Liang;Juang, Jyh-Ching
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.143-148
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    • 2006
  • The goal of this paper is to analyze, through simulations and experiments, GNSS interference mitigation performance under various types of antenna structures against wideband and narrowband interferences using spatial-temporal adaptive signal processing (STAP) techniques. The STAP approach, which combines spatial and temporal processing, is a viable means of GNSS array signal processing that enhancing the desired signal quality and providing protection against interference. In this paper, we consider four types of 3D antenna array structure - Uniform Linear Array (ULA), Uniform Rectangular Array (URA), Uniform Circular Array (UCA), and the Single-Ring Cylindrical Array (SRCA) under an interference environment. Analytical evaluation and simulations are performed to investigate the system performance. This is followed by simulation GPS orbits in interfered environment are used to evaluate the STAP performance. Furthermore, experiments using a 2x2 URA hardware simulator data show that with the removal of wideband and narrowband interference through the STAP techniques, the signal tracking performance can be enhanced.

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마그네슘 합금의 방청을 위한 하이브리드 졸-겔 코팅제의 개발 (Development of Hybrid Sol-Gel Coating to Prevent Corrosion of Magnesium Alloys)

  • 이동욱;김영훈;문명준
    • Corrosion Science and Technology
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    • 제17권1호
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    • pp.30-36
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    • 2018
  • The high rate of corrosion of magnesium alloys makes it limited for industrial applications. Therefore, surface treatment is required to enhance their corrosion resistance. In our study, a chemical conversion coating for protecting the corrosion of the magnesium alloy, AZ31B, was prepared by using a phosphate-permanganate solution. The chemical conversion coating had a limited protection ability due to defects arising from cracks and pores in the coating layer. The sol-gel coating was prepared by using trimethoxymethylsilane (MTMS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) as precursors, and aluminum acetyl acetonate as a ring opening agent. The corrosion protection properties of sol-gel and conversion coatings in 0.35wt% NaCl solution were measured by the electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization test. The EIS results indicated that the resistance of the chemical conversion coating with the sol-gel coating was significantly improved through the sol-gel sealed phosphate-permanganate conversion coating. The results of the potentiodynamic polarization test revealed that the sol-gel coating decreased the corrosion current density ($I_{corr}$). The SEM image showed that the sol-gel coating sealed conversion coating and improved corrosion protection.

Methods of Improving Operational Reliability of Oil Well Casing

  • Sergey A. Dolgikh;Irek I. Mukhamatdinov
    • Corrosion Science and Technology
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    • 제23권1호
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    • pp.1-10
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    • 2024
  • Oil well casing leak is caused by contact of casing outer surface with formation electrolyte. It is usually associated with an aquifer with a high salt content or absence of a cement ring behind the casing. The only way to reduce external casing corrosion is through cathodic protection. Through cathodic polarization of casing structure, electron content in crystal lattice and electron density will increase, leading to a potential shift towards the cathodic region. At Tatneft enterprises, cathodic protection is carried out according to cluster and individual schemes. The main criterion for cathodic protection is the size of protective current. For a casing, the protective current is considered sufficient if measurements with a two-contact probe show that the electric current directed to the casing has eliminated all anode sites. To determine the value of required protective current, all methods are considered in this work. In addition, an analysis of all methods used to determine the minimum protective current of the casing is provided. Results show that the method of measuring potential drop along casing is one of the most reliable methods for determining the value of protective current.

충전탑에서 흡수에 따른 물질전달과 수력학적 거동에 관한 연구 (A Study on Hydraulic Behavior and Mass Transfer by Absorption in Packing Tower)

  • 김석택
    • 한국환경과학회지
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    • 제9권5호
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    • pp.393-396
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    • 2000
  • Packing tower has been used in the chemical industry and the protection of environment for a long time. In the view of environmental protection purification of exhaust gas can be performance effective by gas absorption in counter-current packing tower. In this study characteristics of hydraulic and mass transfer were investigated in D. $0.3m {\times} H. 1.4m$ packing tower with 50mn plastic Hiflow-ring. This study was carried out "Test systems were experimented in conditions of Air, $Air/H_2O. NH_3-Air/H_2O, NH_3-Air/H_2O-H_2SO_4$ and $SO_2-Air/H_2O-NaOH$ under steady state" The extent of test included dry and wetting pressure drop physical law separation efficiency and hold-up as function of gas and liquid load.quid load.

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