• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.717-722
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• 2015

D-limonene included in citrus fruits is obtainable to extract essential oil as well as separate the oil ingredient. Soxhlet extraction, a type of SDE (Simultaneous steam Distillation and solvent Extraction), was used to extract limonene from tangerine peel. HPLC analysis was performed to quantify extracted d-limonene by using reversed-phase HPLC column. Results of HPLC analysis showed that the optimal extraction time was 2 hours in any solvent, and the extracted amounts of d-limonene in tangerine peel (per g tangerine peel) were 7.77 mg, 0.49 mg, and 0.28 mg in ethyl alcohol, n-hexane, and ether. Because yield was the highest in using ethyl alcohol as a solvent, polarity is stronger factor to effect on yield of extraction than boiling point.

• 한국유가공학회:학술대회논문집
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• 2001.05a
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• pp.15-23
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• 2001

It is very interest to use transparent milk for various determination because milk emulsion or colloidal state bring out opacity. The fat globule can disperse by butanone and casein complex can also disintergrate to monomer by action of Triton with aide of SDS and NaOH in same milk phase at time because it can be possible that butanone have amphiphilic characteristic solvent also miscible. Our formulution of solvent can treat almost all type of milk products except with proportion of Triton/Butanone such as 8:2 and 9:1 . In spite of growth inhibition to contact with solvent it call be use also for microbial counting because this formulution did not attactk wall. This is why present technique can be applied to diver determination for the reason of milk payment system, quality control, and national planning or control of national dairy.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.4
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• pp.514-517
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• 2004

Expeller pressed and solvent extracted palm kernel cake (PKC) were force-fed to male and female Muscovy ducks at 7 weeks of age. The nutrient digestibility, apparent metabolizable energy (AME), true metabolizable energy (TME) and true available amino acid (TAAA) digestibilities were determined. There was no significant (p>0.05) effect of the type of PKC used on crude protein (CP), ether extract (EE), metabolizable energy (ME) and amino acid (AA) digestibilities. However, digestibilities of dry matter (DM) and neutral detergent fibre (NDF) was found to be higher in solvent extracted compared to expeller pressed PKC. The average digestibility of DM, CP, NDF and EE were 43, 58, 39 and 89%, espectively. It was found that the ducks utilized about 47% of the gross energy of PKC. The respective average AMEn and TMEn values of PKC for Muscovy ducks was 1,743 and 1,874 kcal/kg. The overall TAAA of PKC for Muscovy ducks was 65%. The data on the TMEn and digestible AA for PKC obtained from this study provide new information with regard to diet formulation for Muscovy ducks.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2009-2014
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• 2007

The aminolysis of diphenyl thiophosphinic chloride (2) with substituted anilines in acetonitrile at 55.0 oC is investigated kinetically. Kinetic results yield large Hammett ρX (ρnuc = ?3.97) and Bronsted βX (βnuc = 1.40) values. A concerted mechanism involving a partial frontside nucleophilic attack through a hydrogen-bonded, four-center type transition state is proposed on the basis of the primary normal kinetic isotope effects (kH/kD = 1.0-1.1) with deuterated aniline (XC6H4ND2) nucleophiles. The natural bond order charges on P and the degrees of distortion of 42 compounds: chlorophosphates [(R1O)(R2O)P(=O)Cl], chlorothiophosphates [(R1O)(R2O)P(=S)Cl], phosphonochloridates [(R1O)R2P(=O)Cl], phosphonochlorothioates [(R1O)R2P(=S)Cl], chlorophosphinates [R1R2P(=O)Cl], and chlorothiophosphinates [R1R2P(=S)Cl] are calculated at the B3LYP/ 6-311+G(d,p) level in the gas phase.

• KSBB Journal
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• v.22 no.3
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• pp.146-150
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• 2007

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] microspheres were prepared using solvent evaporation technique. P(3HB-co-4HB) with 3.9 mol% 4HB was synthesized by fed-batch culture of Ralstonia eutropha. The effects of concentration and type of surfactant (Tween 80, sodium dodecylsulfate, and polyvinyl alcohol), addition of dispersion stabilizer (Acacia), concentration of polymer and model drug (bovine serum albumin) on particle size of the microspheres and their in vitro drug release characteristics were investigated. The average particle size of the microspheres decreased with the addition of dispersion stabilizer and increased with the concentration of surfactant, drug and polymer. Amount of drug release increased with decreasing particle size of the microspheres.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.28-32
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• 2023

We optimized ultrasound-assisted extraction to improve the extraction efficiency of bioactive compounds from the microalgae Acutodesmus reginae. To optimize this extraction process, we investigated the effects of solvent type, solvent concentration, extraction time, extraction number, and extraction power on the production of lutein, α-carotene, β-carotene, and chlorophylls a, and b. After sequential optimization of these main variables, the maximum amount of each compound was extracted at 30℃ with an ultrasound power of 80 W and using 99.5% methanol. Under these optimum conditions, the amount of lutein, α-carotene, β-carotene, and chlorophylls a, and b, were measured as 10.43, 8.66, 3.76, 15.43, and 6.39 mg/g dry matter respectively.

• Journal of the Korean Magnetic Resonance Society
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• v.6 no.1
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• pp.78-83
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• 2002

A new fluoroquinolone (DW-116) with a broad antibacterial spectrum was synthesized by introducing functional fluoropyridyl and methylpyrazine groups on N1, C7 position of quinolone moiety, respectively. $^{1}$H and $^{13}$ C NMR signal assignments and structure were completely elucidated by 2D-NMR methods. Physicochemical properties of products were also investigated. DW-116 is decomposed at 306.9$^{\circ}C$ and the decomposition starts at around 285$^{\circ}C$. The free base form is melt at 280.7$^{\circ}C$ and started to be decomposed immediately. DW-116 has two kinds of polymorphism which is important in drug action but these two plate and rod types have the same solubility in water. However the solubility is quite different in less or polar solvent. The plate type is more soluble in less polar solvent except in dichloromethane.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.358-364
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• 1993

Low foaming scouring agents(SLFS) were prepared by blending of 2-ethylhexylaminoethyl sulfate, Na-dioctyl sulfosuccinate, Newpol PP-2000, MJU-100, ethylene glycol and organic solvent. As the results of several tests, SLFS-2 showed good scouring effect, penetrating ability, emulsifiability and anti-alkaline property, and showed not much water pollution. The foaming power of SLFS-2 measured by Ross & Mites method was 8mm foam height immediately after foaming. And the foaming power of SLFS-2 measured by Ross & Clark method were less than 300mm foam height at $30^{\circ}C$, and 15mm at $80^{\circ}C$. As a result, SLFS-2 was proved as a good low foaming scouring agent.

• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.262-269
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• 1977

The solvolysis of 1-naphthalene-and 2-naphthalenesulfonyl chlorides in acetone-water mixtures have been studied by means of conductometry. The solvent effect and mechanism have been discussed in terms of variation in solvent composition and activation parameters. The reaction was predominantly $S_N2$ type, but bond breaking increased with the increase of water content. The rate constant for 1-naphthyl compound was smaller than that of 2-naphthyl compound due to the ground state stabilization effect and peri-hydrogen effect, and the latter effect was similar to that in ethanol-water mixtures.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04a
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• pp.133-138
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• 2000

MgO thin films were deposited using $Mg(tmhd)_2$ as a precursor dissolved in a solvent by electrostatic spray pyrolysis. When a pure tetra hydro furan was used as a solvent, a large number of particles appeared on the MgO thin film surface due to homogeneous nucleation. However, by adding 1-butyl alcohol or 1-octyl alcohol to THF, homogeneous nucleation was restricted and the number density of the large particles was also drastically reduced. X-ray diffraction analysis showed that the MgO films had a (100) preferred orientation regardless of the type of solvents used. Characterization using Fourier Transformed-Infrared and spectroscopic photometer revealed that the crystallized MgO thin films on the glass substrate had a high optical transmittance (> 85 %) in the visible range. Discharge characteristics of MgO thin films deposited by ESP method on an alternating-current plasma display panel were compared with a MgO thin film prepared by reactive radio-frequency planar magnetron sputtering.