• 한국응용과학기술학회지
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• 제8권1호
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• pp.21-26
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• 1991

The rate constants for the addition reaction of thiourea to nitrone derivatives were determind at various pH and reaction rate equation which could be applied over a wide pH were obtained. The substituent effects and general base catalysis for the addition of thiourea to nitrone derivatives were observed. On the basis of these findings, a plausible reaction mechanism for the nucleophilic addition of thiourea to nitrone was proposed.

• 한국염색가공학회지
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• 제5권2호
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• pp.117-124
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• 1993

The Silk fabric was dyed with various acid dyes, and than treated with copper sulfate or copper sulfate/thiourea. Munsell color system, dye exhaustion and light fastness were investigated for the treated fabrics. The results obtaind are as follows: 1) The color variation of the silk-dyed fabric by aftertreatment with copper sulfate was shown redish, but original color with copper sulfate/thiourea. 2) Copper sulfate/thiourea was much more effective than copper sulfate only to increase the light fastness. 3) The crease recovery was increased by aftertreatment with copper sulfate/thiourea. 4) Dye exhaustion and tensile strength of the silk-dyed fabric by aftertreatment with copper sulfate was decreased about 8-15% more than those of untreated.

• 분석과학
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• 제12권3호
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• pp.209-217
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• 1999

Rose bengal과 thiourea로 각각 감응 및 초감응된 광전류의 감소 원인을 규명하기 위하여 염료용액을 분광학적인 방법으로 분석하였다. 광조사 전후 감응용액의 흡수 및 형광 스펙트럼을 분석하므로서 RB와 TU사이에 일어나는 광촉매 이합체화 반응 기구를 확인할 수 있었다. 또 두 염료분자가 이루는 쌍극자 모멘트의 기하학적 배열은 사각이었으며, 이들 사이의 각도는 $124^{\circ}$임을 알 수 있었다.

• 한국염색가공학회지
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• 제5권4호
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• pp.1-9
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• 1993

The Cotton fabric was dyed with various directd dyes, and then treated with copper sulfate or copper sulfate/thiourea. Munsell color system, dye exhaustion, tensile strength, light fastness, washing fastness and rubbing fastness were investigated for the treated fabrics. The results obtaind are as follows: 1. The color variation of the cotton-dyed fabric by aftertreatment with copper sulfate was shown redish, but original color with copper sulfate/thiourea. 2. Copper sulfate/thiourea was much more effective than copper sulfate only to increase the light fastness, washing fastness and rubbing fastness. 3. Dye exhaustion of the cotton-dyed fabric by aftertreatment with copper sulfate was decreased about 20% more than those of untreated. 4. Tensile stregth of cotton-dyed fabric by aftertreatment with copper sulfate/thiourea was decrease about 10% more than those of untreated.

• Bulletin of the Korean Chemical Society
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• 제15권12호
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• pp.1038-1042
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• 1994

The amperometric responses of thiourea were studied in 0.1 M NaOH by flow injection analysis. D. C. amperometric and pulsed amperometric detection methods were applied for the determination of thiourea at novel metal electrodes such as Pt and Au. Triple-step potential waveforms were adopted in the pulsed amperometric detection. With an optimized pulsed waveform, the current for the oxidation of thiourea was examined with the variation of flow rate of carrier solution and with the change in the amount of sample injected. Gold working electrode turned out to be better in sensitivity and signal to noise ratio than Pt electrode in the pulsed amperometric detection of thiourea. Detection limit is estimated to be 5.33 ${\times}$ 10$^{-5}$ M with this detection method.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.107-113
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• 1995

Benzoyl styrene derivatives were synthesized by Claisen-Schmidt condensation. It was measured that nucleophilic addition of thiourea for benzoyl styrene made use of ultraviolet spectrophotometery at a wide pH $1.0{\sim}13.0$ range in 5% $dioxane-H_2O$ at $40^{\circ}C$. On the basis of general base catalysis, substitutent effect, and confirmation of addtion reaction product, the nucleophilic addtion kinetics of thiourea for benzoylstyrene derivatives were measured by pH change. It maybe concluded that a part was unrelated to pH and another part was in proportion to concentration of hydroxide ion : Above pH 10.0. It was in propotion to concentration of hydroxide ion, a part having no concern with pH was added to the neutral thiourea molecule. From the results of measurement the reaction rate and there findings, nucleophilic addition of thiourea to benzoylstyrene derivative was proposed a fitting mechanism.

• 한국지반공학회지:지반
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• 제11권2호
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• pp.121-138
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• 1995

여러종류의 화합물질들이 동시에 토양에 유출되었을 때 이들이 토양에 흡착하는 정도를 예측 함에는 Langmuir Competitive Model과 IAS(Ideal Adsorption Model) 등이 널리 사용되고 있 는데, 5개의 유기화합물질(Phenol, 2,4-Dichlorophenol, 2,4,6-Trichlorophenot Brucine, Thiourea)과 2종류의 토양을 이용한 흡착실험을 통해서 이 Model들의 예측도를 비교분석하였다. 흡착실험은 이 화합물질들이 독자적인 상태에서 그리고 혼합상태에서 각각 구분하여 실헙하였다. 일반적으로 IAS Model이 Langmuir Model보다 혼합상태에서 각 구성 화합물질들의 흡착을 더 정확히 예측하였다. Langmuir Model은 Phenol과 함께 섞여있는 다른물질의 농도가 높을 때 Phenol의 흡착을 낮게 예측하였다. 두가지 Model모두 Thiourea가 혼합상태에 있을때 흡착정도를 만족스럽게 예측하지 못했는데 Thiourea는 Aliphatic화합물이고 나머지 4개는 Aromatic화합물이다.

• 대한화학회지
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• 제13권3호
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• pp.215-219
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• 1969

Methanol을 溶媒로 한 thiourea와 m- 또는 p- 置換 benzyl bromide 類 와의 反應速度를 電氣傳導度法으로 測定하였다. Hammett 置換基定數와 Log k 와의 關係를 調査한 結果 benzyl bromide에 對한 thiourea의 $SN_2$反應에 있어서 C-Br結合의 解離가 이 反應의 律速段階임을 알 수 있었다. 電子供與基와 電子吸引基는 다같이 反應速度에 定量的인 影響을 주었으나 그 樣式은 서로 달랐다. 이 結果에 符合되는 反應 메카니즘을 考察하였다. 몇 가지 熱力學的 파라미터로 求하였다.

• 한국응용과학기술학회지
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• 제8권2호
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• pp.175-181
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• 1991

The kinetics of the addition of 1-benzylindole-3-(p-substituted) acetophenone derivatives was investigated by ultraviolet spectrophotometery in 30% dioxane -$H_2O\;at\;25^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The Substituent effects on 1-benzylindole-3-(p-substituted) acetophenone derivatives were studied, and addition were facilitated by electron attracting groups. On the base of the rate equation, substituent effect, and general base effect the plausible addition mechanism was proposed : Below pH 3.0, only neutral thiourea molecule was added to the carbon-carbon double bond, and in the range of pH 0.0${\sim}$14.0, netural thiourea molecule and thiourea anion competitively attacted the double bond. By contrast, above pH 10.0, the reaction was dependent upon only the addition of thiourea anion.

• 대한화학회지
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• 제54권1호
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• pp.88-92
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• 2010

이소프로필 멀케푸탄은 중요한 약품 중간체이며 싸이오우레아와 트리글리콜은 이소프로필 멀케푸탄을 합성을 하는데 중요한 화합물이다. 그러므로 트리글리콜 용액에서의 싸이오우레아의 용해는 이소프로필 멀케푸탄의 생산에 중요하다. 트리글리콜용액에서 싸이오우레아의 용해 반응속도론을 조사하고 이소프로필 멀케푸탄을 생산하는 대체 공정을 제시하는것이 본 연구의 목적이다. 트리글리콜용액에서 싸이오우레아의 용해 반응속도론을 조사하기 위하여 용액 농도와 반응 온도를 중점적으로 관찰하였다. 싸이오우레아의 용해속도는 용액농도와 온도가 증가할수록 증가하였다.