• 대한화학회지
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• 제48권1호
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• pp.115-118
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• 2004

• Korean Chemical Engineering Research
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• 제48권5호
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• pp.632-637
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• 2010

1기압 298.15 K에서 water + tetrahydrofuran + butyl acetate + isoamyl alcohol를 포함한 4성분 액-액추출계의 상평형에 대하여 연구하였다. Butyl acetate + isoamyl alcohol을 혼합용매로 사용하였으며, 수용액으로부터 tetrahydrofuran를 추출함에 있어서 혼합용매 사용의 효과를 고찰하기 위하여 각 4성분계에 대한 용해도 곡선, 대응선(Tie-line), 분배도, 선택도를 측정하였다. 또한 실험에 의한 대응선(Tie-line) 데이터를 UNIFAC 모델식으로부터 예측된 값들과 비교한 결과, 액-액평형에 대한 UNIFAC 모델이 본 실험에 설정된 4성분계에 대하여 혼합용매 비율 75/25, 50/50, 25/75에 따라 3.35, 5.21, 5.65%의 편차가 나타남을 알 수 있었다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.17-20
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• 2000

• Journal of Pharmaceutical Investigation
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• 제40권3호
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• pp.193-200
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• 2010

The objective of this study was to investigate the effects of sample preparation, HPLC conditions and peak measurement methods upon determining progesterone content of poly-d,l-lactide-co-glycolide microspheres. A series of the microspheres with different formulations was first prepared. To determine their actual drug contents, the microspheres were dissolved in tetrahydrofuran and diluted with various amounts of methanol to precipitate the polymer. After removal of polymeric precipitates, the filtrates were subject to HPLC analysis under versatile experimental conditions. Interestingly, the composition of a sample solution (e.g., the ratio of methanol to tetrahydrofuran) affected the magnitudes of both peak fronting and peak broadening of progesterone. Its peak became broader and more asymmetrical at lower methanol:tetrahydrofuran ratios. Furthermore, its peak height was influenced by the proportion of tetrahydrofuran in a sample solution. Such problems encountered with tetrahydrofuran were exacerbated when a larger volume of the sample solution was injected onto an analytical column. Under our experimental conditions a peak area measurement provided more accurate and reliable determination of progesterone content in various microspheres than a peak height determination. Optimizing the composition of a sample solution, HPLC chromatographic conditions and peak analysis methods was a prerequisite to an accurate determination of progesterone encapsulated within microspheres.

• Reproductive and Developmental Biology
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• 제33권1호
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• pp.1-5
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• 2009

To search a new pig pheromonal odorant, the $N^1$-allyl-$N^2$-(tetrahydrofuran-Z-ylmethyl)oxalamide molecule predicted by ligand based approach and molecular docking method was synthesized by nucleophilic addition-elimination reaction ($Ad_{NU-E}$) between N-allyloxalamic acid ethylester and tetrahydrofurlmethylamine. According to the evaluation results for efficiency of pig estrus control, the synthesized pig pheromonal $N^1$-allyl-$N^2$-(tetrahydrofuran-2-ylmethyl)oxalamide molecule advanced the estrus by 11.3 days (p<0.05) compared with the non-pheromone group. And from these results, it is predicted that the synthesized pig pheromonal compound will be able to increase the reproduction efficiency of pig.

• 한국식품과학회지
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• 제31권6호
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• pp.1484-1487
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• 1999

Extraction is the most important and tedious step to determine water-soluble vitamin C in water-insoluble chewing gum. For the rapid determination of vitamin C in chewing gum, a new method of dispersion in tetrahydrofuran(THF) was performed. Vitamin C was easily extracted from gum base using THF The content of vitamin C in chewing gum was rapidly quantified with high reliability by an enzymatic method using a chewing gum sample dispersed in tetrahydrofuran.

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.296-298
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• 1986

Carboxylic acid anhydrides are rapidly reduced with borane-lithium chloride (1:0.1) system to give corresponding alcohols (diols in the case of cyclic anhydride) quantitatively in tetrahydrofuran at room temperature. This reagent tolerates aromatic acid ester, nitro, and halide functional groups, however competitively reduces aliphatic ester and nitrile groups.

• Reproductive and Developmental Biology
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• 제32권3호
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• pp.141-146
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• 2008

돼지 페르몬성 냄새 물질을 탐색하기 위하여 tetrahydrofuran-2-yl 계 화합물들과 관측된 결합 친화력상수(Obs.p$[Od]_{50}$) 사이의 정량적인 구조-활성관계(QSAR)로부터 4개 형태의 모델(2D-QSAR, HQSR, CoMFA 및 CoMSIA)들이 유도되었다. Ligand based approache로부터 최적화된 CoMFA 모델(예측성; $r^{2}_{cv.}(q^2)$=0.886 및 상관성: $r^{2}_{ncv.}$=0.984)이 가장 좋은 모델이었다. CoMFA 모델로부터 돼지 페르몬성 냄새 물질로 예측된 $N^{1}$-allyl-$N^{2}$-(tetrahydrofuran-2-yl)methyl) oxalamide (P1), 2- (4-trimethylammoniummethylcyclohexyloxy)tetrahydrofurane (P5) 및 2- (3-trimethylammonium-methylcyclohexyloxy)tetrahydrofurane (P6) 분자들은 비교적 높은 결합 친화력 상수값(Pred.p$[Od]_{50}=8{\sim}10$)과 몇 가지 독성에 대하여 낮은 독성간을 나타내었다.

• Elastomers and Composites
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• 제32권5호
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• pp.302-308
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• 1997

Over 1953/54 Karl Ziegler and Giulio Natta independently discovered new types of catalyst. Thus it was able to produce synthetic cis-polyisoprene rubber which has same properties like natural rubber, since then the amount of consumption was increased rapidly. The problem of disposing of used rubbers has become acute in recent years. cis-Polyisoprene was degraded in supercritical tetrahydrofuran and degree of degradation and product were observed by GPC, FT-IR, GC-MS analyses. As a result, degradation of cis-polyisoprene had small dependency upon the operating pressure, and was inhibited in concentration increase. And cis-polyisoprene was degraded into narrow molecular weight distribution oligomer in 3 hours, and more than 10 organic compounds were produced.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2011-2016
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• 2009

To resolve the differentiation problem of acetone and acrolein in the analysis of carbonyls by high-performance liquid chromatography (HPLC), we investigated the optimum analytical conditions for their separation. Carbonyl compounds were collected by 2,4-dinitrophenylhydrazine (DNPH)-coated cartridges. We examined the influence of three experimental variables: temperature (25, 30, 40, 50 and 60 ${^{\circ}C}$), flow rate (1.0 and 1.2 mL/min), and relative mobile phase composition (among acetonitrile, water and tetrahydrofuran). The experimental results revealed the optimum analytical condition of a flow rate of 1.2 mL/min, temperature of 32 ${^{\circ}C}$ and mobile phase composition of acetonitrile: water: tetrahydrofuran = 34 : 52.8 : 13.2. The analysis of indoor air composition indicated that acrolein and acetone comprised 11% and 42% of all aldehydes, respectively.