• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.906-910
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• 2012

Hollow gold-silver bimetallic nanoparticles (AuAg-HNPs) have been synthesized and their optical and structural properties were characterized. Initially Ag nanoparticles (Ag-NPs) were prepared using poly(ethylenimine) (PEI) as a reducing and a stabilizing agent simultaneously. AuAg-HNPs could then be synthesized via galvanic replacement reaction in a PEI aqueous solution by reacting sacrificial Ag template with a precursor compound of Au, i.e., $HAuCl_4$. Due to the presence of abundant amine functional groups in PEI, which could act as the dissolving ligand for AgCl, the precipitation problem of $Ag^+$ in the presence of Cl from $HAuCl_4$ salt was avoided. On this basis, the relatively high concentrations of $HAuCl_4$ and PEI-stabilized Ag nanoparticles could be used for the fabrication of AuAg-HNPs. Because of their increased surface areas and reduced densities, the AuAg-HNPs were expected and confirmed to outperform their solid counterparts in applications such as catalysis for the reduction of 4-nitrophenol in the presence of $NaBH_4$.

• 한국표면공학회지
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• 제56권1호
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• pp.40-54
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• 2023

In this work, we synthesized a novel electrochemical sensing materials based on tetracarboxylic copper phthalocyanine (TcCuPtc) conjugated PANI (TcCuPtc@PANI). The synthesized materials were employed to modify the screen-printed carbon electrode (SPCE) for the selective sensing of 4-nitrophenol. The TcCuPtc was conjugated with conducting polymer of PANI through the electrostatic interaction and π-π electron conjugation, the polymer film of PANI to inhibit the leakage of TcCuPtc from the surface of the electrode. The prepared TcCuPtc@PANI were characterized and confirmed by scanning electron microscopy (SEM) with EDX, ATR-IR, UV-vis absorption spectroscopy, cyclic voltammetry, and differential pulse voltammetry techniques. The prepared TcCuPtc@PANI/SPCE showed an excellent electrocatalytic sensing of 4-NP in the linear concentrations from 3 to 500 nM with a LOD of 0.03 nM and a sensitivity of 8.8294 ㎂/nM cm^-2. However, the prepared TcCuPtc@PANI/SPCE showed selective sensing of 4-NP in the presence of other interfering species. The practical applicability of the TcCuPtc@PANI/SPCE was employed for the sensing of 4-NP in different water samples by standard addition method and showed satisfactory recovery results.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.278-285
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• 1999

In order to use heat shock promoter for the detection of toxic substances, dnaK promoter was amplified from E. coli genomic DNA by using a polymerase chain reaction(PCR) followed by sequencing and sub-cloning into the multi-cloning site of the plasmid, pUCD615. The pUCD615 is a broad-host-range vector containing promoterless lux operon originated from V.fischeri. The recombinant plasmid was transfered to E. coli DH5$\alpha$ through electroporation. The recombinant E. coli showed several patterns of bioluminescent responses to ethanol stress. The bioluminescent E. coli also showed responses to other toxic substances including FeK3(CN)6, CdCl2, p-nitrophenol and HgCl2. The increases of RLU(Relative Light Unit) were observed at 100ppm of FeK3(CN)6, 10ppm and 100ppm and 100ppm of CdCl2, 1ppm of 10ppm of p-nitrophenol and at 1ppm of HgCl2.

• Applied Biological Chemistry
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• 제18권1호
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• pp.30-41
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• 1975

환경요인(環境要因)으로서 일광(日光), 미생물(微生物), 그리고 벼의 추출액(抽出液)에 존재(存在)하는 조효소(粗酵素)에 의(依)한 치환(置換) Diphenyl Ether계(系) 제초제(除草劑)의 일종(一種)인 MC-4379를 분해(分解)하여 그 분해산물(分解産物)을 TLC, GLC, IR등으로 분석확인(分析確認)하고 모화합물(母化合物)과 분해산물(分解産物)의 식물생육(植物生育)에 대(對)한 조해력(阻害力)을 시험(試驗) 하였다. 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. MC-4379는 광분해(光分解) 결과(結果) amino-MC-4379, 2,4-dichloro-3'-carboxyl-4'-nitro-diphenyl ether, Nitrofen, 2,4-dichloro-3'-carboxyl-4'-amino-diphenyl ether, amino-Nitrofen, 3-carboxymethyl-4-nitrophenel, p-nitrophenol, p-aminophenol과 소량(少量)의 미지화합물(未知化合物)이 생성(生成) 되었고 모화합물(母化合物)은 대부분(大部分) 작용(作用)을 받지 않은 채로 남아 있었다. 또한 photosensitizer로 알려진 benzophenone을 가(加)하면 광분해(光分解)가 더욱 촉진(促進)됨을 확인(確認)하였다. 2. 조효소액(粗酵素液)에 의(依)한 MC-4379의 분해시(分解時)에는 Nitrofen과 소량(少量)의 미지화합물(未知化合物)이 확인(確認)되었으며 대부분(大部分)의 모화합물(母化合物)은 작용(作用)을 받지 않은 채로 존재(存在)하고 있음을 알 수 있었다. 3. Pseudomonas cruciviae와 Aspergillus ustus에 의(依)한 분해시(分解時)에는 Nitrofen과 amino-MC-4379 및 소량(少量)의 미지화합물(未知化合物)이 생성(生成)되었으며 대부분(大部分)은 작용(作用)을 받지않은 모화합물(母化合物)의 형태(形態)로 존재(存在)하였다. 4. MC-4379와 그 분해산물(分解産物) 및 타종(他種) Diphenyl Ether제초제(除草劑)가 식물(植物)의 생육(生育)에 미치는 조해력(阻害力)을 시험(試驗)한 결과(結果) 벼에 있어서는 이들 각화합물(各化合物)(1,000 ppm 유화액(乳化液))의 생육조해력(生育阻害力)은 p-nitrophenol> C-6989 > Nitrofen> amino-nitrofen> MC-4379의 순위(順位)이었고 대두(大豆)에 있어서는 Nitrofen> amino-Nitrofen>MC-4379 의 순위(順位)였다. 잡초중(雜草中) 비름(Amantus blitum)과 강아지풀(Setaria viridis)의 발아(發芽)된 종자(種子)를 사용(使用)하여 이들 화합물(化合物)(500ppm)의 현탁액중(懇濁液中)에서 생육(生育)시켜본 결과(結果) 3일후(日後)에 모두 고사(枯死)하는 현상(現象)을 관찰(觀察)할 수 있었다.

• Archives of Pharmacal Research
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• 제8권4호
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• pp.191-195
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• 1985

The polymerization of title compound (MCEC, I) with phenols led to give corresponding resole type polymer. Phenol and p-methoxyphenol polymer had a relative higher molecular weight and a property of elastomer, but p-chloro-and p-nitrophenol polymer had a lower ones. Also, phenol and p-meth-oxyphenol gave to crosslinking polymer by elongation of reaction period and rising of temperature.

• Journal of Applied Biological Chemistry
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• 제48권1호
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• pp.7-10
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• 2005

Trichoderma sp. SY most effectively produces an extracellular ${\gamma}$-L-arabinofuranosidase (AF) using arabinose as a carbon source. AF grown on cellulose as a carbon source was purified 28-fold with 4.4% yield by DEAE exchange and HQ/20 cation exchange chromatographies The purified enzyme was found to be homogeneous on SDS-PAGE with molecular weight of 89 kDa. It exhibited a high level of activity with p-nitrophenyl ${\alpha}$-L-arabinofuranoside, showing $K_m$ and $V_{max}$ values of $0.15\;{\mu}M$ and $239.85U{\cdot}mg^{-1}$, respectively and did not require any metal ion for activity. It also released p-nitrophenol from p-nitrophenol conjugated ${\beta}$-D-xylopyranoside, and ${\beta}$-D-galactopyranoside not from ${\beta}$-D-glucopyranoside.

• 약학회지
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• 제41권4호
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• pp.492-497
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• 1997

A difference in ethanol metabolism between premature and young adult rats was examined. Female SD rats, either 4wk or 12wk old, were injected with a single dose of ethanol (1.5g /kg) through jugular vein and the blood ethanol level was monitored for 300 min using a gas chromatographic method. Reduction of blood ethanol level per unit of time was less and the area under the blood concentration-time curve (AUC) was significantly greater in young adults compared to premature rats. Activity of hepatic alcohol dehydrogenase was not influenced by the age increase. Total cytochrome P-450, cytochrome $b_5$. or aminopyrine N-demethylation was not different between premature rats and young adult rats. However, p-nitrophenol hydroxylation and p-nitroanisole O-demethylation activities were significantly higher in premature rats. The relative liver weight was 45% greater in premature rats leading to an overall increase in ethanol metabolizing activity in these animals. The results indicate that the reduction in ethanol elimination in young adult rats appears to be mostly associated with the decrease in relative liver weight as the age of animals increases.

• 대한환경공학회지
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• 제33권3호
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• pp.157-161
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• 2011

본 연구에서는 골프장 등에서 살충제로 사용하는 대표적인 농약 중 fenitrothion에 대해 ZVI를 사용하여 분해경로를 파악하고 분해특성을 회분식 반응기를 이용하여 연구하였다. 또한 ZVI에 의한 순수 fenitrothion과 스미치온에 함유되어 있는 fenitrothion 분해율을 비교하였다. ZVI에 의한 fenitrothion의 분해 과정에서 3-methyl-4-nitrophenol과 4-amino-m-cresol이 생성되는 것을 알 수 있었다. ZVI에 의한 순수 fenitrothion 및 스미치온에 함유된 fenitrothion의 분해반응은 1차 반응으로 나타낼 수 있으며, 주입농도가 증가 할수록 분해율 및 1차반응 속도상수 값도 증가하였다. 순수 및 스미치온에 함유된 fenitrothion의 비표면적 1차 속도상수 값은 각각 0.0398 및 $0.1312L/m^2{\cdot}hr$으로 스미치온에 함유된 fenitrothion이 순수 fenitrothion에 비해 ZVI에 빨리 분해되었다. 이는 스미치온에 함유된 계면활성제가 fenitrothion의 용해도를 증가시키며 ZVI의 분산력을 향상시킨 것에 기인하는 것으로 판단된다.

• 생명과학회지
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• 제14권4호
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• pp.582-588
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• 2004

대전 근교의 농약으로 오염된 토양으로부터 파라치온을 분해하는 81균주를 분리한 후, 분리균주들중 파라치온 이용능이 가장 우수한 한 균주를 최종선별하였다. 최종 선별된 균은 생리생화학적 조사와 16S rRNA 염기 서열분석 등을 통하여 Pseudomonas rhodesiae H5로 확인되었다. Pseudomonas rhodesiae H5는 다양한 당을 이용하였으나 sorbose는 이용하지 못하였다. 또 이 균주는 ampicillin, spectinomycin, mito-mycin C에는 일부 저항성을 가지나 kanamycin, chloram-phenicol에는 저항성을 나타내지 않았다. 그리고 $BaCl_2$, LiCl, $MnSO_4$등의 중금속에서는 mg/ml 단위까지 강한 내성을 나타냈다. Pseudomonas rhodesiae H5의 최적 생장 조건은 3$0^{\circ}C$, pH 7.0 이었고, 이 균주는 파라치온의 organophosphate bond를 가수분해하여 p-nitrophenol를 생성한 후 ortho-ring cleavage를 거쳐 중심대사에 연결되는 것으로 추정된다.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2519-2521
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• 2013