• 대한의생명과학회지
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• 제23권4호
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• pp.395-401
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• 2017

Various preclinical and clinical trials have been conducted the efficacy of celastrol. In data presented in the current manuscript is the first trial to inhibit Helicobacter pylori with celastrol. In this study, the quantitative change of various H. pylori proteins including CagA and VacA by the anti-bacterial effect of celastrol was determined. The anti-H. pylori effects of celastrol was investigated by performing 2-dimensional electrophoresis and additional supporting experiments. After 2-dimensional electrophoresis analysis, spot intensities were analyzed and then each spot was identified using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) or peptide sequencing using Finnigan LCQ ion trap mass spectrometer (LC-MS/MS). The results show that celastrol has multiple effects on protein expression in H. pylori.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1991년도 추계학술발표회논문집
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• pp.64-68
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• 1991

It happened that there was a sudden peak with the capacity of change, when I measured the capacity of change, cubical expansion and Thermally Stimulated Current on the Cross - Linked Polythylene. Crystal melting began at 375 K and changed into formaless shapeless at 380 K. The conduct of a particle on the surfase of dipole, electron trap was founded to be ion conduction nature under the low electronic field, wherase, the electron nature under the high electronic field. Consequentity, under the semi-conduction layer electronic a particle was injected to inter-fase and accumulated for a time and appeared to be TSC.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.401.3-402
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• 2002

Enalapril (ENP) maleate is effective drug for the treatment of renivascular hypertension and heart failure. ENP acts as inhibitor of the enzyme angiotensin-convertase (ACE-inhibitor) and metabolized to enalaprilat (ENPT), which is the active metabolite that is really responsible for the therapeutic action. In the present study, a sensitive and rapid liquid chromatography/ electrospray ion trap tandem mass spectrometry (LC/MS/MS) method combined with high-throughput solid phase extraction (SPE) has been developed and validated for the simultaneous quantitative determination of ENP and ENPT in human plasma. (omitted)

• 한국군사과학기술학회지
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• 제7권3호
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• pp.110-121
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• 2004

Pyrolysis-mass spectrometry, incorporating an in situ thermal hydrolysis and methylation(THM) step, has been used to study biological materials for bacteria, toxin and virus. Newly developed pyrolyzer was used to decompose biological materials, and tetramethylammonium hydroxide(TMAH) was used as a methylation reagent. Chemical ionization(CI) using ethanol and ion trap mass spectrometer(ITMS) were used to ionize and analyze of pyrolysis components, respectively. Analytical characteristics of bacteria (including spore), virus and toxin were analyzed. Also acquisition and interpretation of mass spectra as biomarkers for classification/identification of biological material s were explained.

• Mass Spectrometry Letters
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• 제2권1호
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• pp.20-23
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• 2011

The purpose of this study is to investigate the in vitro metabolism of hesperetin, a bioflavonoid. Hesperetin was incubated with rat liver microsomes in the presence of NADPH and UDP-glucuronic acid for 30 min. The reaction mixture was analyzed by liquid chromatography-ion trap mass spectrometer and the chemical structures of hesperetin metabolites were characterzed based on their MS/MS spectra. As a result, a total of five metabolites were detected in rat liver microsomes. The metabolites were identified as a de-methylated metabolite (eriodictyol), two hesperetin glucuronides, and two eriodictyol glucuronides.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.566-568
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• 2003

The phosphor $CaTiO_3:Pr^{3+}$ attracts much attention as a low-voltage red phosphor because of its good chromaticity and intrinsic conductivity. The addition of Ga into this CaTiO₃:Pr led the luminance intensity to greatly enhance without the change of the wavelength for the electronic transition and the peak shape of it. The increase of the recombination rate of electron-hole pairs through the Ga ion doping, which was expected to play a role of a hole-trap center, is proposed to be one of the reasons for the enhancement of the cathodoluminescence intensity.

• 한국군사과학기술학회지
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• 제8권3호
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• pp.83-91
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• 2005

Pyrolysis-mass spectrometry has been used to characterize the 17 biological materials including bacteria and proteins. In this study, an in situ thermal-hydrolysis methylation(THM) procedure using tetramethylammonium hydroxide(TMAH) was employed. The biological materials are ionized using chemical ionization(CI) method with ethanol by ion trap mass spectrometer(ITMS), which attached with our own made pyrolyzer module, and then their pyrolysis mass spectra were obtained. The major distinct characteristic peaks were selected from all the range of mass spectra, and analyzed using principal component analysis(PCA) method to assess the classification/identification possibility of biological materials.

• 분석과학
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• 제17권1호
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• pp.85-89
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• 2004

라일락 꽃 향기 성분의 특성을 고체상 포집 용매추출법과 기체크로마토그래피 이온 포집형 질량분석법으로 연구하였다. 라일락 품종에 따라 향기성분의 조성이 현저한 차이를 보였다. 백색 라일락 꽃의 경우 벤즈알데히드, 페닐 아세트알데히드 및 알파-파네센인데 비하여 보라색 라일락 꽃은 벤즈알데히드, 알파-피넨 및 오시멘이 주된 향기성분으로 발견되었다. 라일락 꽃 향기성분 중 알파-피넨의 거울상 이성질체의 본질을 분석한 결과 ( )형태임을 알 수 있었다.

• 한국전기전자재료학회논문지
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• 제29권5호
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• pp.268-273
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• 2016

In this study, we observed current-voltage characteristics of the MIM (metal-insulator-metal) structure. The $WO_x$ material was used between metal electrodes as the oxide insulator. The structure of the $Al/WO_x/TiN$ shows bipolar resistive switching and the operating direction of the resistive switching is clockwise, which means set at negative voltage and reset at positive voltage. The set process from HRS (high resistance state) to LRS (low resistance state) occurred at -2.6V. The reset process from LRS to HRS occurred at 2.78V. The on/off current ratio was about 10 and resistive switching was performed for 5 cycles in the endurance characteristics. With consecutive switching cycles, the stable $V_{set}$ and $V_{reset}$ were observed. The electrical transport mechanism of the device was based on the migration of oxygen ions and the current-voltage curve is following (Ohm's Law ${\rightarrow}$ Trap-Controlled Space Charge Limited Current ${\rightarrow}$ Ohm's Law) process in the positive voltage region.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1990년도 추계학술대회 논문집
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• pp.98-101
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• 1990

In order to investigate the laser effects resulted from the behaviors of carriers for BOPP film, experiment of TSC were carried out on the specimen with 15[$\mu\textrm{m}$] thick irradiated by He-Ne laser. The TSC spectras were observed in the temperature range of -100[$^{\circ}C$] to 130[$^{\circ}C$] with the electric field of 20∼60[MV/m], had show four of the distinguished peak such as ${\alpha}$$_1$, ${\alpha}$$_2$, ${\beta}$ and ${\gamma}$, which appeared at 115, 80, 17 and -30[$^{\circ}C$] respectively. Specially, ${\alpha}$$_1$ was observed and anomalous TSC flowing in the same direction as the charging current on the high-electric field such as 50∼60[MV/m]. In according on the consequences obtained from the studies, the origin of ${\alpha}$$_1$peak was attributed to the detrapping process form trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.