• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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• pp.47-48
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• 2011

The effect of solution acidity and organic additives, polyethylene glycol (PEG), on the trivalent chromium electroplating was systematically investigated in the view point of solution stability, electroreduction of trivalent chromium ions and characterization of deposition layer. It was found that, the concentration of fraction chromium complexes in the trivalent chromium bath containing formic acid is strongly depended on pH value. PEG molecules were stable in trivalent chromium bath containing formic acid via studies on electrospray ionization mass spectrometry (ESI-MS) and UV-Vis. However, the presence of PEG molecules decreased the reductive current of hydrogen evolution, increasing of current efficiency higher about 10 % compared with solutions without PEG. Moreover, PEG additives developed the nodular morphology during electroreduction of trivalent chromium ions with the increase of solution acidity and enhanced its current efficiency by maintaining the consumption of complexant, formic acid, at a low speed. In this study, the effect of solution acidity was emphasized important, there, it controlled the formation of complexes in the solution, cathodic film (CF) during deposition, and properties of deposited layer. By electrochemical quartz crystal microbalance (EQCM), studies show that chromium electrodeposition occurs via the formation of intermediate complexes and adsorption on the cathode surface, which hinder the penetration of ions from bulk solution to the cathode surface.

• 약학회지
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• 제52권1호
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• pp.12-19
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• 2008

The organic acids (formic acid, acetic acid and propionic acid), phenol and benzopyrene in wood vinegar were determine by HPLC. An $Atlantis^{TM}dC_{18}$ column with a acetonitrile: 0.1% phosphoric acid (5: 95, organic acids), acetonitrile: water (10 : 90, phenol), 100% acetonitrile (benzopyrene) as a mobile phase was used. Retention time of acetic acid, formic acid, propionic acid, phenol and benzopyrene was 4.77, 3.73, 9.08, 30.97 and 6.10 min, respectively. The calibration curves of organic acids, phenol, benzopyrene were linear over the concentration range of $30{\sim}500,\;60{\sim}1000$, and $3{\sim}50\;{\mu}g/ml$ with correlation coefficient of above 0.999. The limit of detection (LOD) and limit of quantitation (LOQ) of acetic acid, formic acid, propionic acid, phenol, and benzopyrene was 1.71 and 5.19, 1.11 and 3.35, 4.87 and 14.74, 6.45 and 19.55, 0.08 and $0.24\;{\mu}g/ml$, respectively. The coefficients of variation for intra- and inter-day assay were $0.21{\sim}4.14$ and $0.07{\sim}1.19%$, respectively and the precision was $95{\sim}115%$. From this study, we suggest that HPLC is suitable method for the determination of organics in wood vinegar and could be applied to quality control of wood vinegar.

• Korean Chemical Engineering Research
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• 제54권6호
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• pp.753-761
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• 2016

Liquid-liquid extraction (LLE) can be used for the recovery of acetic acid from black liquor prior to bioethanol fermentation. Recovery of value-added chemicals such as acetic-, formic- and lactic acid using LLE from Kraft black liquor was studied. Acetic acid and formic acid have been reported to be strong inhibitors in fermentation. The study elucidates the effect of three reaction parameters: pH (0.5~3.5), temperature ($25{\sim}65^{\circ}C$), and reaction time (24~48 min). Extraction performance using tri-n-octylphosphine oxide as the extractant was evaluated. The maximum acetic acid concentration achieved from hydrolyzates was 69.87% at $25^{\circ}C$, pH= 0.5, and 36 min. Factorial design was used to study the effects of pH, temperature, and reaction time on the maximum inhibitor extraction yield after LLE. The maximum potential extraction yield of acetic acid was 70.4% at $25.8^{\circ}C$, pH=0.6 and 37.2 min residence time.

• 청정기술
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• 제22권4호
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• pp.281-285
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• 2016

난분해성 1,4-다이옥산을 분해시키기 위하여 촉매습식과산화반응에 활성적인 Cu wire촉매를 사용하였다. Cu wire 촉매를 사용함으로써 1,4-다이옥산의 완전한 분해가 가능하였으나, 분해된 1,4-다이옥산은 완전 무기화($CO_2$와 $H_2O$로 전환)되지 못하고 중간생성물인 ethylene glycol diformate, oxalic acid, formic acid, formaldehyde, acetaldehyde 등으로 전환되었다. 1,4-다이옥산이 분해되어 없어짐에 따라 formaldehyde와 oxalic acid가 점진적으로 나타나기 시작하여 증가하다가 최고농도를 보인 후 다시 감소하였다. 이들 두 중간체의 최고농도 도달시점에 acetaldehyde의 농도가 급격히 증가하여 최고농도를 보인 후 다시 감소하였다. 이들 세가지 중간물질의 감소와 함께 ethylene glycol diformate, formic acid가 생성되기 시작하여 그 농도가 점진적으로 증가하였다. 이들은 연속적인 과정을 통해 생성되었다. Cu wire 촉매는 반응이 진행되는 동안 활성이 떨어지지 않고 매우 안정적이었다.

• KSBB Journal
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• 제8권1호
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• pp.36-41
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• 1993

본 연구는 포름알데히드를 분해하는 균주를 하천의 진흙에서 6종 분리하고 그 중에서 포름알데히드의 분해능이 가장 우수한 균주인 H-5을 분리동정하여 Pseudomonas putida H-5라고 명명 하였다. Pseudomonas putida H-5의 최적 생장조건은 온도 $30^{\circ}C$, pH 7.0이었고, 포름알데히드는 0.02~0.04% 의 농도에서 가장 분해가 잘 되었고, 기질로는 glucose가 가장 우수하였다. Pseudomonas putida H-5에 의하여 포름알데히드는 메탄올과 개미산으로 분해되며 이는 균주의 생육에 아무런 영향을 미치지 않았다.

• 공업화학
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• 제19권1호
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• pp.129-132
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• 2008

본 연구는 정제과정에 따른 대나무 기름의 물리 화학적 특성 및 성분을 검토하기 위해 타르, 색차계, 총 유기산 및 총 페놀성 물질 함량, 조 단백질 및 조 지방 함량, 유리 당 및 기름성분, 유기산 및 무기물을 분석하였다. 정제과정을 통해 타르 성분이 약 78% 이상 감소되었으며 색차계 분석에서 명암이 정제의 샘플에서 92.4로 나타내어 투명해졌고 적색도는 29.1에서 3.0으로 낮아졌다. 총 유기산 및 총 페놀성 물질 함량은 정제과정 중에 각각 약 63%와 80%가 감소되었다. 조 단백질 및 조 지방 함량은 정제과정 중에 각각 약 60, 56% 감소했고, 유리 당 별로는 lactose 함량이 가장 많았고 다음으로 fructose, glucose 순이었다. 미 정제 및 정제 대나무 기름에서 palmitoleic acid의 함량이 가장 많았고 다음으로 stearic acid, linoleic acid 순이었다. 총 유기산 함량은 정제과정 중에 약 88%의 유기산이 감소되었고 formic acid가 가장 많았다. 양이온 함량은 미 정제 기름의 Ca 함량이 가장 많았고 다음으로 K, Na, Fe 순이었으며, 정제 기름은 Ca 함량이 가장 많았고 다음으로 Fe, K, Na 순이었다.

• 한국염색가공학회지
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• 제11권2호
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• pp.55-63
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• 1999

The purpose of this study was to investigate the purification of chitin and chitosan for textile finishing agent from crab shell. Weight loss rate(removing Ca and protein), degree of deacetylation, solubility and MIC(Minimum growth inhibitory concentration) value of chitosan and molecular weight of the treated crab shell were measured. The results of this study were as follows : 1) Weight loss rate(removing Ca) of crab shell treated with HCI increased with the concentration of HCI and treatment time, but it became constant over 60 min. of treatment time. 2) Weight loss rate(removing protein) of crab shell treated with NaOH(0.5N∼2N) increased with the concentration of NaOH and treatment temperature and time, but it became constant above loot of temperature and over 200 min. of treatment time. 3) Degree of deacetylation of chitin treated with NaOH increased with the concentration of NaOH(40∼60％), but molecular weight decreased and thus MIC value increased. 4) Concentration of acetic acid should be above 0.3％ to dissolve chitosan easily. Solubility for chitosan was the highest with formic acid, and the next was acetic acid, hydrochloric acid, lactic acid and sulfuric acid in order.

• Current Research on Agriculture and Life Sciences
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• 제3권
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• pp.70-78
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• 1985

본(本) 실험(實驗)은 견층(繭層) seicin에 대(對)한 몇가지 화학약제(化學藥劑) 처리(處理)의 온도별(溫度別), 농도별(濃度別) seicin 용해성(溶解性)에 미치는 영향(影響)을 조사(調査)하였던 바 다음과 같은 결과(結果)를 얻었다. 1. 공시(供試) 해서촉진제중(解舒促進劑中) 견층(繭層) seicin의 용해촉진력(溶解促進力)이 가장 큰 약제(藥劑)는 sodium peroxide($Na_2O_2$)였으며, sodium carbonate($Na_2CO_3$), sodium sulfite($Na_2SO_3$) ammonia water($NH_4OH$)의 순(順)으로 용해촉진력(溶解促進力)이 작았다. 2. 공시(供試) 해서억제제중(解舒抑制劑中) 견층(繭層) sericin의 용해억제력(溶解抑制力)이 가장 큰 약제(藥劑)는 tannic acid($C_{14}H_{10}O_9$)였으며, stannic acid($S_n(OH)_4$), formic acid(HCOOH)< methyl alcohol($CH_3OH$)의 순(順)으로 용해억제력(溶解抑制力)이 작았다. 3. 공시(供試) 해서억제제중(解舒抑制劑中)에서 formic acid와 stannic acid는 $100^{\circ}C$의 고온(苦蘊)에서는 견층(繭層) sericin의 용해(溶解)를 크게 촉진(促進)하였다. 4. 공시(供試) 해서억제제중(解舒抑制劑中) methyl alcohol의 경우(境遇)는 저농도(低濃度)에서는 용해억제력(溶解抑制力)이 전혀 없었다.

• 한국염색가공학회지
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• 제13권4호
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• pp.264-271
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• 2001

Catalytic wet oxidation of ethylene glycol as refractory compound was studied in a batch slurry reactor using lwt% $Pt/A1_2O_3$, lwt% $Pt/TiO_2,\;Mn/CeO_2$(1:1) and 5wt% $Mn/Al_2O_3$. Experiments were conducted to investigate theeffects of temperature, initial ethylene glycol concentration, catalyst dosage and PH on the ethylene glycol decomposition. When compared with the uncatalyzed reaction, the use of catalysts could increase the rate of ethylene glycol decomposition. The lwt% $Pt/A1_2O_3$ catalyst was preferable to the other catalysts for the destructive oxidation of ethylene glycol. The reaction rate was first order with respect to initial concentration of ethylene glycol. In acidic condition the removal efficiency of ethylene glycol was good, but there was a significant leaching of platinum. Small amount of acetic acid, oxalic acid, masonic acid and formic acid as intermediates were detected during catalytic wet air oxidation of ethylene glycol.

• 한국동물위생학회지
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• 제34권3호
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• pp.285-289
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• 2011

This study was conducted to determine the content of non-steroidal anti-inflammatory drugs (NSAIDs) in meats available on the Korean markets. The analysis was carried out using following conditions; C18 column ($100{\times}2.1$ mm, 1.7 ${\mu}m$), mobile phase composed of DW (containing 0.1% formic acid): acetonitrile (containing 0.1% formic acid), binary pump at a flow rate of 0.3 ml/min and 5 ${\mu}l$ of injection volume, MS/MS detector with ESI positive mode. The calibration range of five NSAIDs showed linearity ($r^2{\geq}0.99$) at concentration range of 3.125~200 ${\mu}g$/kg. The recoveries in fortified muscle more than 78.7~100.3%. The detection limits for meloxicam, ketoprofen, flunixin, carprofen and tolfenamic acid were 3.5, 1.6, 1.7, 9.8 and 4.8 ${\mu}g$/kg, respectively. We also monitored NSAIDs residue in cattle muscle 51 samples. The test results, NSAIDs were all not founded.