• Applied Biological Chemistry
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• 제34권1호
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• pp.26-31
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• 1991

한국산 고구마 중 분질인 수원 147과 점질인 황미로부터 전분을 분리하고 이화학적 특성을 비교하였으며 아밀로펙틴의 분자구조적 성질을 조사하였다. 수원 147 전분은 황미전분에 비하여 팽윤력이 낮고 호화개시온도가 높았다. ${\beta}-Amyloysis\;limit(%)$는 수원 147 아밀로펙틴이 57.6%, 황미 아밀로펙틴이 57.0%를 나타내었고, 평균사슬길이는 수원 147 아밀로펙틴이 24.8 포도당단위, 황미 아밀로펙틴이 21.9 포도당단위였다. 아밀로펙틴을 pullulanase로 가지절단처리한 후 Sephadex G-50으로 분획한 결과는 중합도($\overline{DP}\;35{\sim}45$)와 $\overline{DP}\;10{\sim}20$의 bimodal 분포를 나타내었으며 두 아밀로펙틴간 peak의 중합도에서 차이가 있었다.

• 약학회지
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• 제45권6호
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• pp.634-640
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• 2001

Ibuprofen is one of the nonsteroidal anti-inflammatory drugs (NSAID) and has shown antiinflammatory; antipyretic, and analgesic activity in both animals and humans. But it causes gastric mucosal abnormalities including edema, erythema, and submucosal petechial hemorrhages and erosin in human. In addition, based on the pharmaceutical point of view the compression and dissolution ability of ibuprofen is known as poor. Therefore we studied to develop novel formulation containing water-insoluble drug, ibuprofen, using microemulsion consisting of surfactant, oil phase, and water phase was prepared for the purpose of increasing its bioavilability The physicochemical properties such as particle size, dissolution rate, solubility of ibuprofen in the system were determined. After oral administration of ibuprofen containing the microemulsion system, to Sprague-Dawley rats, pharmacokinetic parameters were also obtained. For the formulation in the study, oleic acid, linoleic acid, and several kinds of glycerides and triglycerides were used as an oil phase with several surfactants. Diethylene glycol monoethyl ether (Transcuto $l^{ }$) or saturated polyglycolized glycerides (Labrafil $^{ }$)as surfactant was used, the domain of microemulsion was wide. The diameter of o/w microemulsion was ranged from 90 to 220 nm. Microemulsion, prepared with unsatulated polyglycolized glycerides (Labrafil $^{ }$) and the 2 : 1 molar mixture of diethylene glycol monoethyl ether (Transcuto $l^{ }$)/polyoxyethylene(4) lauryl ether (Bri $j^{ }$ 30) , is expected to be promising system that increased the bioavilability of ibuprofen.ibuprofen.

• Environmental Engineering Research
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• 제24권4호
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• pp.608-617
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• 2019

The adsorption of sulfamethoxazole (SMX) onto a NaOH-activated pine wood-derived biochar was investigated via batch experiments and models. Surprisingly, the maximum adsorption capacity of activated biochar for SMX (397.29 mg/g) was superior than those of pristine biochars from various feedstock, but comparable to those of commercially available activated carbons. Elovich kinetic and Freundlich isotherm models revealed the best fitted ones for the adsorption of SMX onto the activated biochar indicating chemisorptive interaction occurred on surface of the activated biochar. In addition, the intraparticle diffusion limitation was thought to be the major barrier for the adsorption of SMX on the activated biochar. The main mechanisms for the activated biochar would include hydrophobic, π-π interactions and hydrogen bonding. This was consistent with the changes in physicochemical properties of the activated biochar (e.g., increase in sp² and surface area, but decrease in the ratios of O/C and H/C).

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.91-94
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• 2003

In this work, the physicochemical properties for permeant molecules and polyion complex membrane prepared by complexation between SA and chitosan were determined by using molecular modeling methods, and the permeation behaviors of water and alcohol molecules through the PIC membrane have been investigated. In the case of penetrant molecule, the experimental results showed that the prepared membrane was excellent pervaporation performance result in most solution, and the selectivity and permeability of the membrane were dependent on the molecular size, the polarity and the hydrophilic surface of permeant organics. However, the separation behavior of methanol aqueous solution exhibited other permeation tendency with other feed solutions and contradictory result. That is, the membrane were preferentially permeable to methanol over water despite water molecule has stronger polarity and small molecular size than methanol molecule. In this study, the results were discussed from the viewpoint of chemical and physical properties between permeant molecules and membrane in the diffusion state.

• KSBB Journal
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• 제8권3호
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• pp.209-216
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• 1993

미생물을 이용한 생분해성 고분자 생산연구의 일환으로 토양으로부터 고점성의 생물고분자 생산균주를 분리하고, 이 분리균에 대한 분류학적 성질 및 생성 생물고분자의 이화학적 성상을 검토, 규명하였다. 분리균주는 Alcaligenes속의 한 균종으로 동정하였으며, 호알카리성 균주의 특성을 나타내었다. CPC(cetylpridinium chloride)침전 및 acetone처리하여 정제한 산성 고분자 물질은 carboxyl기를 갖고 자외 흡수가 강한 glutamic acid만을 구성성분으로 하였고, glutamic acid는 $\gamma$-peptide 결합의 $\gamma$-polyglutamic acid로 존재하였다. 중화당량은 약 350으로 $\gamma$-PGA 2.7잔가당 1개의 음이온이 존재하였으며, 분자량은 약 $6.5{\times}10^5$Daltons이었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
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• pp.145-145
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• 2000

M-CeO2 (M : noble metal) catalysts have been widely studied as three-way catalysts and methanol synthesis catalysts. Ceria is thought to play a number of roles in these catalysts. The Ce(IV)/Ce(III) redox pair may store/release gases under oxidizing/reducing conditions, extending the operational window. Additionally, metal-ceria interactions lead to several effects, including the dispersion of the active components and promoting the activation of molecules such as CO or NO. Pd is a promising component to current TWC formulations and behaves particularly well when compared with Pt and Rh-based catalysts for low-temperature oxidation of Co and hydrocarbon. However the effect of Pd-ceria interactions on the physicochemical properties of Pd and the redox properties of Ce is not elucidated yet. In order to know exactly about the metal-ceria interactions, the model study are expecting to give a better environment, resulting in the wide use of the surface science tools. The substrate was Si(100) wafer, on which Ta metal was sputtered as a thickness of 100nm. The CeO2 thin film of 30nm was deposited by using the magnetron sputtering. Spin coating and magnetron sputtering methods were used to make the Pd thin film layer. The prepared sample was investigated by in-situ XPS, AES, SEM and AFM analysis.

• Food Science and Biotechnology
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• 제17권4호
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• pp.734-738
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• 2008

The physicochemical and in vitro physiological properties of soluble dietary fiber (SDF) from wax gourd (Benincasa hispida) pulp and peel were investigated. The pulp was composed of 11.4% SDF and 24.3% insoluble dietary fiber (IDF), while the peel contained 3.2% SDF and 43.3% IDE The predominant sugar in the SDF of the wax gourd pulp and peel was uronic acid, followed by galactose and rhamnose. The SDFs from the wax gourd pulp and peel gave similar elution patterns, with 4 main neutral sugar and uronic acid peaks eluted by 0.4, 0.5, 1, and 2 M ammonium acetate buffer. The pulp SDF had a much higher glucose retardation index (GRI) than the peel SDF for all measurement times. The pulp SDF showed strong growth-inhibiting activity against Escherichia coli and Clostridium perfringens, whereas the peel SDF produced strong growth-promoting activity against Bifidobacterium longum, Bifidobacterium infantis, and Lactobacillus brevis when compared to glucose.

• 한국식생활문화학회지
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• 제36권6호
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• pp.640-648
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• 2021

In this study, when manufacturing Yakgwa, 0, 25, or 50% of embryonic rice flour (ERF) was substituted for wheat flour (WF) to make the dough. After making Yakgwa by hot air frying (HF) or deep-fat frying (DF) methods, physicochemical characterization and acceptance tests were conducted. ERF had a higher water-binding capacity and a lower fat-binding capacity than WF (p<0.05). Yakgwa prepared by HF had lower crude fat contents, peroxide values, and expansion rates, but higher hardnesses, lightnesses, and rednesses (p<0.05) than that prepared by DF. Higher ERF substitution ratios reduced acid values and expansion rates and increased hardness (p<0.05). Acceptance testing showed 0% ERF Yakgwa prepared by HF had a significantly higher acceptance than Yakgwa prepared by DF. HF was found to have a positive effect on product acceptability. Yakgwa prepared with the DF method by substituting WF with ERF resulted in better flavor and overall acceptability than Yakgwa prepared with WF alone (p<0.05).

• Advances in concrete construction
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• 제11권5호
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• pp.367-374
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• 2021

The present study investigated the effect of the combined carbonation and steam curing on the physicochemical properties and CO₂ uptake of the Portland cement concrete. Four different curing regimes were adopted during the initial 10 h of curing to evaluate the potential of carbonation curing as an alternative to conventional steam curing in the precast concrete industry from environmental and practical viewpoints. Four combinations of carbonation and steam curing conditions were applied as curing regimes to the samples at an early age. The test results indicated that the samples treated with the combined carbonation and steam curing exhibited higher early strength development compared to the other samples, signifying that carbonation curing can reduce the production time of precast concrete. Furthermore, the CO₂ uptake capacity of the samples was calculated and found to be as high as 18% with respect to the mass of the paste samples. Hence, the simultaneous utilization of steam and CO₂ for the fabrication of precast concrete members has the potential to make precast concrete greener and more cost-effective.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.524-533
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• 2021

In this study, a series of anion conductive organic/inorganic composite membranes with excellent ionic conductivity and chemical stability were prepared by introducing graphene oxide (GO) inorganic nanofiller into the quaternized poly(phenylen oxide (Q-PPO) polymer matrix. The fabricated organic/inorganic composite membranes showed higher ionic conductivity than the pristine membrane. In particular, Q-PPO/GO 0.7 showed the highest ionic conductivity value of 143.2 mS/cm at 90℃, which was 1.56 times higher than the pristine membrane Q-PPO (91.5 mS/cm). In addition, the organic/inorganic composite membrane showed superior dimensional stability and alkaline stability compared to the pristine membrane, and the physicochemical stability was improved as the content of inorganic fillers increased. Therefore, we suggest that the as-prepared organic/inorganic composite membranes are very promising materials for anion exchange membrane applications with high conductivity and alkaline stability.