• 한국표면공학회지
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• 제37권2호
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• pp.86-91
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• 2004

Effect of potassium formate, glycine and oxalic acid in a sulfate solution on the deposit composition and current efficiency of trivalent chromium plating was studied. The trivalent chromium layers prepared by solutions with potassium formate, glycine and oxalic acid contain a few carbon inside. The solutions containing potassium formate, glycine and oxalic acid are relatively stable with pH change. The solution with the potassium formate shows 6-30％ current efficiency with current density, whereas, the solutions with oxalic acid and glycine show about 5％ current efficiency, respectively. The improved current efficiency is related to enough supply of chromium ions to the electrode due to the increase of pH at the front of electrode.

• 한국도로학회논문집
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• 제18권6호
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• pp.25-34
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• 2016

OBJECTIVES : This is a basic research for the domestic production of airport-airside deicers. This research selected basic materials for deicers appropriate for the pavement of domestic airports by evaluating the deicing performances of basic materials used in international-standard airport deicers and their impacts on pavements. METHODS : Laboratory investigation was conducted to evaluate the asphalt surface tensile strength, concrete scaling impact, ASR impact, and deicing performances of sodium formate (NaFm), potassium formate (KFm), sodium acetate (NaAc), and potassium acetate (KAc), which are the basic de-icing materials commonly used at international airports, approved by the FAA. In addition, the analyses were also performed on the airside deicer urea, which is currently used in domestic airports. RESULTS : Laboratory investigation confirmed that sodium formate, potassium formate, sodium acetate, and potassium acetate had superior surface tensile strength, concrete scaling impact, and deicing performance compared to airside urea, but they also had greater impacts on concrete ASR. Among these materials, sodium formate had the best asphalt surface tensile strength, concrete scaling impact, and deicing performance, while also having the greatest impact on ASR; hence, mitigation plans for ASR were needed, if it were to be used as airport-airside deicer. CONCLUSIONS : It is necessary to consider additional additives to prevent ASR of concrete pavements when developing airport-airside deicers using sodium formate, potassium formate, sodium acetate, and potassium acetate.

• 공업화학
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• 제30권3호
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• pp.384-388
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• 2019

동절기 고속철도차량 하부 및 대차부에 부착된 설빙이 차량 운행 시 도상자갈구간(침목이 받는 차량 하중 전달 및 침목 고정을 위한 자갈 구간)에서 고속으로 낙하하여 자갈을 비산시켜 이로 인한 철도차량 구조물 및 시설물의 피해가 보고되고 있으며, 이는 고속철도 개통 이후 지속되고 있다. 이러한 문제점 해결을 위해 자갈의 비산을 방지하는 네트, 인력 제빙, 이동식 열풍기 등을 사용하고 있으나 효율성이 떨어진다. 기존보다 효율적인 제빙을 위해 화학적 제빙액에 대한 연구가 진행되고 있으며, 본 연구에서는 화학적 제빙액으로 사용되는 물질들의 융빙성능, 동점도, 증발성 등을 평가하여 고속철도차량 제빙용으로 최적의 물질을 찾고자 한다. 평가 물질로는 유기산염류 4종(개미산나트륨, 초산나트륨, 개미산칼륨, 초산칼륨)과 알코올류 2종(프로필렌글리콜, 글리세롤)을 대상으로 하였다. 이때, 실내 평가에서는 개미산칼륨, 초산칼륨, 프로필렌글리콜이 유사한 융빙성능을 보였으나, 모사 살포 시스템을 이용한 융빙성능 결과, 프로필렌글리콜이 가장 우수한 성능을 보였다. 이는 프로필렌글리콜의 동점도가 2.989029 St로 다른 물질 대비 높아 얼음에서 보다 오래 체류하여 제빙하기 때문이다. 또한, 개미산칼륨과 초산칼륨은 결정이 석출되어 차량외관에 악영향을 미치므로 사용에 어려움이 있다. 본 연구를 통해 프로필렌글리콜이 고속철도차량용 제빙액으로 최적의 물질임을 확인하였다.

• 분석과학
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• 제19권4호
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• pp.323-332
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• 2006

This paper discusses several low-temperature heat-tranfer fluids, including water-based inorganic salt, organic salt, alcohol/glycol mixtures, silicones, and halogenated hydrocarbons in order to choose the best heat-transfer fluid for the newly designed direct contact refrigeration system. So, it contains a survey on commercial products such as propylene glycol and potassium formate as newly used in super market and food processing refrigeration. The stability of commercial fluids at the working temperature of $-20^{\circ}C$ was monitored as a function of time up to two months. And organic and inorganic compositions of candidate fluids were obtained by analytical instruments such as ES, XRF, AAS, ICP-AES, GC, and GC-MS. Analysis results indicate that commercial propylene glycol is very efficient and safe heat transfer fluids for the direct cooling system with liquid phase.

• The Korean Journal of Physiology and Pharmacology
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• 제2권5호
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• pp.581-589
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• 1998

A regulating mechanism of the ATP-sensitive potassium channels $(K_{ATP}\;channels)$ is yet to fully explained. This study was carried out to investigate the effects of intracellular application of monocarboxylates (acetate, formate, lactate, and pyruvate) on $K_{ATP}$ channels in isolated rabbit ventricular myocytes. Single channel currents of $K_{ATP}$ channels were recorded using the excised inside-out or permeabilized attached (open-cell) patch-clamp technique at room temperature. Intracellular application of acetate, formate and pyruvate led to an inhibition of channel activity, whereas intracellular application of lactate increased channel activity. These effects were reversible upon washout. Analysis of single channel kinetics showed that monocarboxylates did not affect open-time constant and close-time constant. These results suggest that monocarboxylates participate in modulating $K_{ATP}$ channels activity in cardiac cells and that modulation of $K_{ATP}$ channels activity may resolve the discrepancy between the low $K_i$ in excised membrane patches and high levels of intracellular ATP concentration during myocardial ischemia or hypoxia.

• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.447-452
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• 2017

A $Pd/TiO_2$ catalyst was prepared by a conventional impregnation method, and further characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-Vis spectroscopy. The as-prepared material was employed to accelerate dehydrogenation of potassium formate in the presence of light at different temperatures. The $Pd/TiO_2$ catalyst showed distinct dehydrogenation activities, and particularly, the material exhibited a higher turnover frequency (TOF) of $2,097h^{-1}$ at $80^{\circ}C$ after 10 minutes in the presence of light compared to that (TOF of $1,477h^{-1}$) obtained in the absence of light. Numerous analytical techniques suggest that the increased dehydrogenation activity likely originates from light-excited electron and hole at the photocatalyst, i.e., $TiO_2$, in conjunction with metal-support interaction.

• 한국표면공학회지
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• 제10권3호
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• pp.3-11
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• 1977

3가크롬 鍍金法은 6가크롬 鍍金法의 諸 欠点을 克服할 수 있다는 事실이 알려져 外國에서는 오래 前 부터 工業的 실用化를 위한 硏究가 活潑하게 行하여 졌고, 이중 최근에 發表된 Alecra 3 process는 電着諸特性이 뛰어난 方法으로 裝飾크롬 鍍金 分野에 利用되고 있다고 한다. 本 硏究는 Alecra 3 process의 浴 組成中 개미산칼륨으로, 염화칼륨을 염화나트륨으로 大替한 浴의 電着諸特性을 調査하고 最適 염化크롬의 濃度와 錯化比를 함께 調査하여 다음과 간은 結果를 얻었다. (1) 外觀, 被覆性,均一電着性 및 平均 電析 速度 등은 염화크롬 濃度가 0.4 mol일때 가장 良好하였다. (2) 개미산나트륨 대 염화크롬의 mol比는 염화크롬이 0.4 mol일때 2~3이 比較的 良好한 電着諸特性을 보여 주었다. (3) 개미산나트륨 및 염화나트륨 含有한 鍍金浴의 電着諸特性은 Alecra 3 Process의 特性과 비슷하였다.

• Journal of Animal Science and Technology
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• 제49권4호
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• pp.481-490
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• 2007

본 시험은 대조구, 항생제 처리구:Avilla- mycin?? 6ppm, MOS 처리구:MOS 250ppm, lectin 처리구:Mannosespepecific lectin 12.5ppm, Organic acid F 처리구:FORMI??(formic acid 35.4%, formate 34.6%, potassium 30.0%) 0.3%, Organic acid G처리구: GALLACID?? 0.06% 등 6처리구를 두고 이들 처리가 산란계에 미치는 영향을 비교 평가하기 위하여 생산성, 혈액성상, 혈청 IgG, 장내 미생물 균총을 조사하였다. 사양시험은 48주령의 산란계(Hy-Line Brown??) 900수를 선별하여 6처리, 5반복, 반복당 15케이지, 케이지당 2수씩 A형 2단 케이지에 수용하고 randomized block design으로 배치하였다. 6주 동안의 산란율(hen-day, hen- house egg production)에서는 MOS 처리구가 가장 높은 산란율을 보였고 모든 첨가구가 대조구보다 산란율이 높았다(P<0.05). 난중은 lectin 처리구가 가장 높았으며 모든 첨가구들이 대조구보다 높은 경향이 있었다. 연파란율은 lectin 처리구를 제외한 모든 첨가구들이 대조구보다 낮았다(P<0.05). 난황색은 Organic acid G 처리구를 제외한 모든 첨가구들이 대조구보다 높았다(P<0.05). Haugh unit는 lectin 처리구가 가장 높았으며 모든 첨가구들이 대조구보다 높았다. Leukocytes 중 SI는 lectin 처리구가 가장 높았다(P<0.05). Erythrocytes 중 RBC, HB, MCHC는 lectin 처리구가 가장 높았으며 MOS 처리구가 가장 낮았다(P<0.05). 장내 미생물에서는 처리구간에 유의적인 차이는 없었으나 Lactobacilli 수는 대조구보다 첨가구들이 높은 경향이 있었고 Cl. perfringens 수는 Organic acid F를 제외한 모든 첨가구들이 대조구보다 낮은 경향이 있었다. 혈청 IgG 농도는 MOS 처리구가 가장 높았으며 모든 첨가구들이 대조구보다 유의적으로 높았다(P<0.05). 결론적으로 본 시험에서 사용된 면역조절제(MOS, Lectin)와 유기산제는 산란계에서 항생제(Avilamycin??)와 유사한 생산성을 나타내어 항생제 대체제로서 산란계의 생산성을 효과적으로 개선 할 수 있으며 특히 이중에서 MOS의 생산성 개선효과가 가장 높았다.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.375-380
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• 2015

Recently, methane has attracted much attention as an alternative carbon feedstock since it is the major component of abundant shale and natural gas. In this work, we produced methanol from methane using whole cells of Methylosinus trichosporium OB3b as the biocatalyst. M. trichosporium OB3b was cultured on NMS medium with a supply of 7:3 air/methane ratio at 30℃. The optimal concentrations of various methanol dehydrogenase inhibitors such as potassium phosphate and EDTA were determined to be 100 and 0.5 mM, respectively, for an efficient production of methanol. Sodium formate (40 mM) as a reducing power source was added to enhance the conversion efficiency. A productivity of 49.0 mg/l·h, titer of 0.393 g methanol/l, and conversion of 73.8% (mol methanol/mol methane) were obtained under the optimized batch condition.

• 한국표면공학회지
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• 제37권2호
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• pp.80-85
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• 2004

Chromium-carbon (Cr-C) and chromium-carbon-phosphorus (Cr-C-P) alloy deposits using trivalent chromium sulfate baths containing potassium formate were prepared to study their current efficiency, hardness change and phase transformations behavior with heat treatment, respectively. The current efficiencies of Cr-C and Cr-C-P alloy deposits increase with increasing current density in the range of 15-35 A/dm$^2$. Carbon content of Cr-C and phosphorous of Cr-C-P layers decreases with increasing current density, whereas, the carbon content of Cr-C-P layer is almost constant with the current density. Cr-C deposit shows crystallization at $400^{\circ}C$ and has (Cr+Cr$_{ 23}$$C_{6}$) phases at $800^{\circ}C$. Cr-C-P deposit shows crystallization at $600^{\circ}C$ and has (Cr+Cr$_{23}$ $C_{6}$$+Cr_3$P) phases at $800^{\circ}C$. The hardness of Cr-C and Cr-C-P deposits after heating treatment for one hour increase up to Hv 1640 and Hv 1540 and decrease about Hv 820 and Hv 1270 with increasing annealing temperature in the range of $400～^{\circ}C$, respectively. The hardness change with annealing is due to the order of occurring of chromium crystallization, precipitation hardening effect, softening and grain growth with temperature. Less decrease of hardness of Cr-C-P deposit after annealing above $700^{\circ}C$ is related to continuous precipitation of $Cr_{23}$ $C_{6}$ and $Cr_3$P phases which retard grain growth at the temperature.