• Biomolecules & Therapeutics
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• 제5권3호
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• pp.228-232
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• 1997

AU-164 was synthesized as a reversible gastric $H^+/K^+$ ATPase inhibitor, and its effects were tested in various systems. AU-164 inhibited rabbit gastric $H^+/K^+$ ATPase with an $IC_{50}$/ of 9 $\mu$M. On the other hand, AU-164 was a weak inhibitor for dog kidney $Na^+/K^+$ ATPasc, indicating the selectivity for gastric $H^+/K^+$ ATPase. The reversible property of the AU-164-induced inhibition of $H^+/K^+$ ATPase was confirmed by filtering the inhibition mixture through Sephadex G-25M column. In vivo basal acid secretion was also inhibited by AU-164 under the pylorus ligation of Sprague-Dawley rats. In addition, AU-164 protected dose dependently gastric lesion induced by ethanol in rats. The $ED_{50}$ value of 62 mg/kg p.o was estimated. These results suggest that AU-164 is a potent, selective and reversible gastric $H^+/K^+$ ATPase inhibitor, and that AU-164 has a potential use for the clinical therapeutics of peptic ulcer disease.

• Archives of Pharmacal Research
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• 제22권2호
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• pp.137-142
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• 1999

Anti-ulcer activity of newly synthesized acylquinoline derivatives was investigated. For the in vitro screening, the effects of compounds on gastric $H^{+}/K^{+}$ ATPase isolated from hog and rabbit were examined. Among them, AU-090, AU-091, AU-254, AU-413 and AU-466 exhibited good in vitro activity on both enzymes. To correlate the in vitro activity with in vivo action, the effects of the compounds on the basal gastric acid secretion were studied. Some derivatives showed considerable anti-secretory activities, and AU-413 was selected for further studies. AU-413 protected gastric damage induced by either ethanol or NaOH dose dependently when given orally. $ED_{50}$ values of 12 mg/kg, p.o. (ethanol) and 41 mg/kg, p.o. (NaOH) were obtained. In addition, histamine-stimulated gastric secretion was reduced upon AU-413 administration. Taken together, newly synthesized acylquinoline derivatives, especially AU-413, is worthy of further investigation to be developed as an anti-ulcer agent.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 추계학술발표대회 개요집
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• pp.219-221
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• 2005

Sn-9Zn solder balls were bonded to Cu, ENIG (Electroless Nickel/Immersion Gold) and electrolytic Au/Ni pads, and the effect of aging on their joint reliability was investigated. The interfacial products were different from the general reaction layer formed in a Sn-base solder. The intermetallic compounds formed in the solder/Cu joint were $Cu_{5}Zn_{8}$ and $Cu_{6}Sn_{5}$. After aging treatment, voids formed irregularly at the bottom side of the solder because of Sn diffusion into the $Cu_{5}Zn_{8}$ IMC. In the case of the solder/ENIG joint, $AuZn_{3}$ IMCs were formed at the interface. In the case of the Au/Ni/Cu substrate, an $AuZn_{3}$ IMC layer formed at the interface due to the fast reaction between Au and Zn. In addition, the $AuZn_{3}$ IMC layer became detached from the interface after reflow. When the aging time was extended to 100 h, $Ni_{5}Zn_{21}$ IMC was observed on the Ni substrate.

• Bulletin of the Korean Chemical Society
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• 제8권2호
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• pp.122-126
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• 1987

Oribtal energies for AuH and AgH are calculated by an all-electron relativistic self-consistent-field method using Slater type basis functions. Major relativistic effects for AgH are spin-orbit splittings and those for AuH are large shifts in orbital energies in addition to spin-orbit splittings. Relativistic effects on orbital energies in AgH and AuH imply that changes in correlation energies for relativistic calculations of AuH will be significantly larger than those of AgH, providing partial explanation for the large discrepencies in equilibrium bond length and the dissociation energy between experiments and theoretical estimates for AuH. Large relativistic effects on orbital energies indicate that relativistic contributions should be included for the correct interpretation of ionization potentials for these molecules. Relativistic effects are also evident in dipole moments for these molecules.

• 펄프종이기술
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• 제31권1호
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• pp.1-9
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• 1999

This study was performed to investigate the deinkability of Korean old newspaper(KONP) and the properties of newsprint made from deinked pulp with some addition of virgin pulp. When the samples of composed of 50% Australian old magazine(AuOMG) and 50% KONP were compared with the samples 50% AuOMG and 50% AuONP, the yield, opacity, strength properties of the former were high, but its brightness was low. When the mixing ratio of AuOMG : AuONP : KONP was 30:20:50, the brightness and strength properties were obtained the similar or better than those obtained samples having other mixing ratio. The brightness and opacity of samples made from deinked pulp with the some addition of TMP and BKP can meet the minium qualifications of brightness and opacity specified by Japanese Industrial Standard. The samples, which DIP, TMP, and KP were mixed with the ratio of the 85:10:5 and 90:5:5, maintained higher brightness and strength comparing to the samples containing higher amount of virgin pulp. Since the newsprint samples made from KONP was not inferior to those from imported old newspaper, the more use of KONP in producing newsprint is recommended.

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.188-196
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• 2013

We have investigated the effects of formalin on the assembly of colloidal gold nanoparticles (AuNPs) prepared by laser ablation of a solid gold target in deionized water. Upon addition of formalin, the surface plasmon resonance (SPR) band at 519 nm for pure AuNPs decreases and shifts to red while a new broad SPR band appears at ~700 nm. The red-shift is prominent with increase in the incubation time. The average size of the initial AuNPs is around 12 nm but it increases to 23 nm after addition of formalin. It turns out that formalin acts as a cationic surfactant for AuNPs with negative surface charge in the colloidal solutions. Furthermore, through analysis of the Raman spectrum of formalin and the density functional theory calculations, we confirm that methanediol is the main species in formalin which is in charge of the aggregation of AuNPs.

• 한국지구과학회지
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• 제35권4호
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• pp.259-266
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• 2014

폐 PCBs의 스크랩으로부터 염소-차아염소산염 용액을 이용하여 Au와 Ag를 친환경적이고 효과적으로 용출시키고자 하였다. PCBs에 Cu, Sn, Sb, Al, Ni, Pb, Au 등과 같은 유용금속이 함유되어 있는 것을 EDS 분석으로 확인하였다. 최대 Au 용출율은 1%의 광액농도, 2:1의 염산:차아염소산나트륨 그리고 2 M의 NaCl 농도조건이다. Au 회수율이 가장 높은 메타중아황산나트륨 농도는 3 M에서였다. 염소-차아염소산염이 폐 컴퓨터에 함유되어 있는 Au와 Ag를 효과적으로 용출시킬 수 있는 용매제 임을 그리고 메타중아황산나트륨이 Au를 간단하게 침전시킬 수 있는 첨가제임을 확인하였다.

• 한국표면공학회지
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• 제55권2호
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• pp.120-132
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• 2022

In the non-cyanide-based electroless Au plating solution using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent, analysis of each component constituting the plating solution is essential for the analysis of the reaction mechanism. And component analysis in the plating solution is important for monitoring component changes in the plating process and optimizing the management method. Capillary Electrophoresis (CE) method is rapid, sensitive and quantitative and could be readily applied to analysis of Auⁿ⁺ ion, complexing agent and reducing agent in electroless Au plating solution. In this study, the capillary electrophoresis method was used to analyze each component in the electroless Au plating solution in order to elucidate the complex bonding form and the plating mechanism of the non-cyanide-based electroless Au plating bath. The purpose of this study was to establish data for optimizing the monitoring and management method of plating solution components to improve the uniformity of precipitation and stability. As a result, it was confirmed that the analysis of thiomalic acid as a complexing agent and Auⁿ⁺ ions and the analysis of aminoethanethiol as a reducing agent were possible by capillary electrophoresis. In the newly developed non-cyanide-based electroless Au plating solution, it was confirmed that Auⁿ⁺ ions exist in the form of Au⁺ having a charge of +1, and that thiomalic acid and Au⁺ are combined in a molar ratio of 2 : 1. In addition, it was confirmed that aminoethanethiol can form a complex by combining with Au⁺ ions depending on conditions as well as acting as a reducing agent.

• 한국재료학회지
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• 제26권10호
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• pp.556-560
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• 2016

Using current-voltage (I-V) and capacitance-voltage (C-V) measurements, the electrical properties of Au and Cu Schottky contacts to n-Ge were comparatively investigated. Lower values of barrier height, ideality factor and series resistance were obtained for the Au contact as compared to the Cu contact. The values of capacitance showed strong dependence on the bias voltage and the frequency. The presence of an inversion layer at the interface might reduce the intercept voltage at the voltage axis, lowering the barrier height for C-V measurements, especially at lower frequencies. In addition, a higher interface state density was observed for the Au contact. The generation of sputter deposition-induced defects might occur more severely for the Au contact; these defects affected both the I-V and C-V characteristics.

• Bulletin of the Korean Chemical Society
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• 제27권3호
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• pp.403-406
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• 2006

The surface structure and electrochemical behavior of self-assembled monolayers (SAMs) formed by aromatic thiols on Au(111) were investigated by scanning tunneling microscopy (STM) and cyclic voltammetry. Benzenethiol (BT) forms disordered phases on Au(111) which are composed of many bright domains, while benzyl mercaptan (BM), with a methylene unit between the aromatic group and sulfur atom, forms twodimensional ordered SAMs on Au(111). In addition, two phase-separated domains consisting of disordered and ordered phases were observed in binary SAMs formed from a 1 : 1 mixed ethanol solution of BT and BM. From STM and CV measurements, we found that the blocking efficiency of aromatic thiol SAMs coated on an Au(111) electrode for an electron transfer reaction decreases as the structural order of the SAMs increases. Molecular-scale STM and CV results obtained here will be very useful in designing functional SAMs for further applications, such as the improvement of corrosion passivation of Au(111) on an aromatic thiolmodified Au(111) surface.