• Applied Biological Chemistry
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• v.51 no.3
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• pp.219-222
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• 2008

In the search for third generation herbicidal cyclic imide derivatives, the average values of herbicidal activity ($pI_{50}$) in vivo (pre-emergence) of 40 new peroxidizing herbicides, 1-(4-chloro-2-fluoro-5-propargyloxyphenyl)thiourea derivatives (1-40) against rice plant (Orysa sativa) and barnyard grass (Echinochlor crus-galli) were studied. The molecular similarity between protoporphyrinogen IX (protogen) as the substrate of protox enzyme and Urea derivatives (1-40) was discussed quantitatively. The diallyl (20) and 3-nitro substituent (33) showed the selective herbicidal activity against barnyard grass. Allyl substituent (8) and their molecular similarity in dice (S=0.81) showed the highest levels of herbicidal activity ($pI_{50}$=4.71). Also, similarity indices (S) and superimposed volume (C) of protogen and aryl-substituents (21-40) showed good correlation.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.103-110
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• 2008

To develop the third generation herbicidal cyclic imide (Cyl) derivatives, the new 1-(4-chloro-2-fluoro-5-propargyloxyphenyl)-3-thiourea derivatives were synthesized and measured their herbicidal activities ($pI_{50}$) in vivo (preemergence) against rice plant (Orysa Sativa) and barnyard grass (Echinochlor crus-galli). The synthetic yields (%) of aryl derivatives (21-40) in general was higher than that of alkyl derivatives (1-20). In case of alkyl derivatives, the synthetic yield depended on the structural forms of alkyl amine groups. From the results of correlation analysis between herbicidal activities and substituents, the compound 8 and 24 showed the highest herbicidal activity against the shoot and root of barnyard grass. Especially, the compounds 11 and 6 showed the selective herbicidal activities between rice plant and barnyard grass.

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1449-1454
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• 2014

The co-sensitization of N719 with a cyclic thiourea functionalized organic dye, coded AZ5, for dye-sensitized solar cells (DSSCs) was demonstrated. Due to its intensive absorption in ultraviolet region, AZ5 could compensate the loss of light harvest induced by triiodide, thereby the short-circuit photocurrent density ($J_{sc}$) was increased for co-sensitized (N719+AZ5) DSSC. Moreover, the electron recombination and dye aggregation were retarded upon N719 cocktail co-sensitized with AZ5, thus the open-circuit voltage ($V_{oc}$) of co-sensitized device was enhanced as well. The increased $J_{sc}$ (17.9 $mA{\cdot}cm^{-2}$) combined with the enhanced $V_{oc}$ (698 mV) ultimately resulted in an improved power conversion efficiency (PCE) of 7.91% for co-sensitized DSSC, which was raised by 8.6% in comparison with that of N719 (PCE = 7.28%) sensitized alone. In addition, co-sensitized DSSC exhibited a better stability than that of N719 sensitized device probably due to the depression of dye desorption.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.142-149
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• 1999

Moisture absorption rate of rice according to the soaking time was higher at $25^{\circ}C$ than 4$^{\circ}C$ and the op-timum soaking time was 1hr at $25^{\circ}C$. When the ratios of added water for rice cooking were 1.3 in an elec-tric cooker and pressure cooker and 1.7 in an Dookbaeki sensory an mechanically evaluation of cooked rice were highly evaluated. The total number of peak on gas chromatography profile were 89 in an press-ure cooker 56 in an electric cooker and 83 in an Dookbaeki and major volatile compounds of cooked rice were aliphatic hydrocarbons cyclic hydrocarbons aromatic hydrocarbons aldehydes alcohols ketones and thiourea. Furan that is in sweety was not detected in volatile components of cooked rice of electric cooker.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.30-30
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• 2018

스마트 도금공장을 구축하기 위해서는 도금액 내부의 화학 물질 농도 변화를 측정할 수 있는 화학 센서 기술이 필수적으로 요구된다. 와트욕은 대표적인 고속 니켈 도금액 중 하나로 기본적으로 황산니켈, 염화니켈, 보릭산의 염과 함께 케리어(type-1 광택제), 광택제(type 2-광택제), 응력 제어제 등의 유기 첨가제로 구성되어 있다. 이러한 유기 첨가제는 전차된 니켈층의 두께 균일도, 조도, 미세 구조, 내부 응력 등 다양한 특성을 제어하며, 정밀한 농도 관리가 필수적으로 요구되나, 분석 기술의 부재로 인하여 지금까지도 대부분의 액관리는 할셀법이나 작업자의 경험에 의존하고 있다. Cyclic voltammetry stripping(CVS) 방법은 전기화학 분석 과정에서 나타나는 첨가제의 가속, 감속 특성 등과 여기에 수반되는 stripping peak의 변화를 이용하여 개별 첨가제의 농도를 측정하는 방법이며, 지금까지 인쇄회로기판의 비아필 공정, 전해 동박 제조, 반도체 배선 등 구리도금 산업 전반에 걸쳐 첨가제 관리에 효과적으로 적용되고 있다. 그러나 수소 발생으로 인한 stripping 효율 문제로 인하여 니켈, 주석, 아연 등 표준 환원 전위가 높은 금속 도금액 내부 첨가제 농도 측정은 아직 어려운 상황이다. 본 연구에서는 이 문제를 극복하기 위해 염소를 과량 첨가한 구리 도금액을 CVS 분석의 base 용액으로 이용하여 니켈 도금액 내부 여러 광택제 (polyetylene glycol(PEG) 계열, thiourea 계열, 2-butyne-1,4-diol 등) 농도를 측정하는 법을 제시하였다. 제시된 방법은 CVS 분석 과정에서 구리-염소 사이의 상호 작용으로 인해 생성되는 3가지 stripping peak의 상대적인 크기 변화가 첨가제 농도에 따라 영향을 받는다는 사실에 기반하였다. 본 연구에서는 여기에 관한 원인에 대해 고찰하였으며, 제시된 방법을 통해 광택제 계열 첨가제 농도 측정을 선택적으로 할 수 있다는 것을 증명하였다.

• Analytical Science and Technology
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• v.10 no.3
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• pp.216-224
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• 1997

In the study of cyclic voltammogram of rubeanic acid, rubeanic acid has two reduction peaks; first peak is similar with that of $S^{2-}$ and thiourea, which is conceded to by HgS, second peak is very weak and unidentified. The study also describes the differential pulse cathodic stripping voltammetric method for the determination of rubeanic acid. The followings were optimal conditions of rubeanic acid for the study : 0.05M borate buffer solution(pH 10.0) ; an accumulation potential of -0.30V(vs. Ag/AgCl); accumulation time of 120sec. : scan rate of 10mV/sec. The detection limit of trace analysis shows $2.7{\times}10^{-8}M$ of rubeanic and at optimal conditions.