• 대한화학회지
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• 제34권1호
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• pp.85-90
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• 1990

Tetrakis(picolinato)tungsten(IV) 착물에 과량의 methylpicolinic acid를 가하여, 무극성 용액에서 얼마나 inert한지를 60 ~ 120$^{\circ}C$ 및 키실렌의 환류조건에서 분광학적 방법을 관찰하였다. 산소접촉 여부에 무관하게 90$^{\circ}C$에서 2일간은 inert하였으나 산소접촉하에서는 존재하는 리간드농도 제곱에 역비례하는 속도상수를 보이며 급격히 산화되며 리간드를 잃었다. Ar기체하에서 sealing한 시료는 반응속도상수 [k($sec^{-1}$)] = $8.8{\times} 10^{-7}$를 보이며 50일까지 반응속도론적으로 안정하였다. 배위된 질소의 인접 양성자($H_6$)의 화학적 이동은 없었으나 리간드를 잃음에 따라 intensity가 감소하였으며 새로운 유리리간드의 $H_6$ peak가 생성됨을 확인하여 치환반응은 일어나지 않고 착물이 산화되며 리간드를 잃고 있음을 확인하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.34.2-34.2
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• 2009

The ceramic coatings on metallic materials have attracted by many researchers due to the chemical inertness of ceramic materials. In such aspect, SiOC is a promising material tobe used as protective coating layer on metallic materials due to its outstanding thermal stability and chemical inertness. In this research, SiOC coating was carried out onto SuS-316 substrate using Cl free preceramic polymers such aspolyphenylcarbosilane. 20% of polymethylphenylsilane in cyclohexane solution was coated onto metal surface by dip coating method. Thermal oxidation was carried out at $200^{\circ}C$ for crosslink of the preceramic polymer and the sample was pyrolysized at $800^{\circ}C$ under argon to convert the preceramic polymer to amorphous SiOCx state. The microstructure of the SiOCx film after pyrolysis was investigated using FE-SEM. Corrosion resistance of SiOC coated SuS-316 substrate has been investigated using 5% HCl solution at 25, 40, 60 and $80^{\circ}C$ for 7days. The data revealed that the corrosion resistance increased with SiOC coating on SuS-316 substrate.

• 센서학회지
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• 제27권5호
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• pp.340-344
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• 2018

Electrodes are an important part of electrocardiography (ECG); disposable electrodes have been extensively used. However, personal ECG monitoring devices for Internet of Things applications require reusable electrodes. As there have been no systematic studies on the characteristics of reusable electrodes to date, we conducted this study to assess the performance and feasibility of electrodes with different materials. We built reusable electrodes using twelve different metallic materials, including commonly used copper, silver, zinc, plating materials, chemically inert titanium, stainless steel, and aluminum. Each electrode was fabricated to a size of $5{\times}10mm$. Their characteristics such as offset, baseline drift, stabilization time, and chemical inertness were compared. A personal ECG monitoring system was used to test the manufactured electrodes. The performances of the Ag, Cu, and Zn electrodes were better than the performances of other electrodes. However, these materials may not be used owing to the chemical changes that occur when the electrodes are in contact with the skin, such as discoloration and corrosion, which deteriorate their electrical characteristics. Titanium, stainless steel, and aluminum are chemically stable. The titanium electrode showed the best performance among the three, and it is our recommendation as a material for manufacturing reusable electrodes.

• 해양환경안전학회지
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• 제4권1호
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• pp.1-12
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• 1998

The Ministry of Maritime Affairs and Fisheries embarked on Oct. 8, 1996, incorporating most of the previously fragmented maritime administrations into one single organization But the maritime administrative functions related to safely and security missions have not yet been merged into a synergetic whole, with versatile multi-functional systems working so effectively that better services to the public might be expected. Enhancing administrative capabilities requires that these missions be integrated into one institution and an enterprising management system be adopted to overcome bureaupathologies, such as complacency and inertness of administration.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1997년도 Proceedings of KIN-CIN Joint Symposium 97 on Safety of Shipping and History of Maritime Communication between Korea and China around 9th Century
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• pp.13-33
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• 1997

The Ministry of Maritime affairs and Fisheries embarked on Oct. 8, 1996, incorporating most of the previously fragmented maritime administrations into one single institution. But the maritime administrative functions related to safety and security missions have not yet been merged into a synergetic whole, with versatile multi-functional systems working so effectively that better services to the public might be excepted. Enhancing administrative capabilities to meet future demands with limited resources requires that these missions be integrated into one institution and an enterprising management system be adopted to overcome bureaupathologies, such as complacency and inertness of administration.

• 대한화장품학회지
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• 제23권3호
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• pp.75-81
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• 1997

It has been used that fluorinated compounds could be applied to cosmetic products. It is that fluorinated conpounds are hydrophobicity and lipophobicity. These fluorinated compounds are reported to form a highly protective and effective film against most aggressive chemical and physical agents. PerfluropolymethyoisopropylEther has homophobicity and are colorless, odorless, tasteless and non-greasy. In this we made a success to formulate the new type of hand care cream using PFPE. PFPE are suitable thickness and chemical inertness to skin. The reason that we select PFPE for this investigation. We developed the new type hand care cream by adsorption and dispersion of PFPE. There are very stable dispersion and highly moisture diffusion control. And these characteristics were verified by actual consumer test.

• 대한방사성의약품학회지
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• 제5권2호
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• pp.129-134
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• 2019

Over a few decades, copper radioisotopes and their chelation chemistry for radiopharmaceuticals have played crucial role in the radiopharmaceutical science area. A variety of chelators have been required for their stable targeting ability in physiological conditions. For radiolabeling with copper-64 into biomolecules, thermodynamic stability, kinetic inertness, pH stability, and redox stability should be considered. In this regard, many researchers have attempted to develop the chelators that can bind with copper more tightly, rapidly and stably for copper radiolabeling. This review discusses the chemistry of copper, its suitable chelators and characteristics, while elucidating the evaluations of each chelator for radiolabeling.

• Journal of Electrochemical Science and Technology
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• 제9권2호
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• pp.149-156
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• 2018

In this technical note, I report the analysis of electrochemical impedance data measured with potential sweeping. Even though the instruments for voltammetric impedance measurements have been developed for decades using different approaches, their applications are limited due to the lack of well-established protocols to easily analyze voltammetry data. To fill this gap, the singular point of the specific potential is considered that is only determined by the standard/formal potential and the transfer coefficient and is independent of the kinetics and experimental parameters (including revertability) of faradaic reactions. Taking the advantage of its inertness, I suggest an approach employing the singular point as a reference to obtain general electrochemical information. As all the concepts and methods are verified with numerical simulations, this technique is expected to be applied for complex reactions involving electrochemical and chemical reaction mechanisms.

• Journal of Mechanical Science and Technology
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• 제19권4호
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• pp.936-946
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• 2005

The liquid nitrogen as an environmentally safe coolant has been widely recognized in cryo­genic machining, its function as a lubricant is plausible due to its chemical inertness, physical volatility and low viscosity. Since a reduced friction is a direct witness of the lubrication effect from a tribological viewpoint, this paper presents an evaluation of the apparent friction coefficient on the tool-chip interface in cryogenic cutting operations to prove and characterize the lubricity of LN2 in cryogenic machining. The cryogenic cutting technology used in this study is based on a cooling approach and liquid nitrogen delivery system which are intended to apply liquid nitrogen in well-controlled fine jets to selectively localized cutting zones and to penetrate liquid nitrogen to the tool-chip interface. It has been found that the apparent friction coefficient can be significantly reduced in cryogenic machining, depending on the approach of liquid nitrogen delivery.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 추계학술대회 논문집
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• pp.7-11
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• 2000

In this paper was studied on the mechanical characteristics of Glass Fiber Reinforced Plastics(GFRP) of the steel bar it is to replace. The advantage of FRP such as high strength, low weight and chemical inertness or noncorrosiveness can be fully exploited. GFRP bar were successfully fabricated at l0mm nominal diameters of solid and hollow types using a pultrusion method. Tensile and bending specimens from this bar were tested and compared with behavior of GFRP rebar and steel bar.