• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.506-510
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• 2007

Vacuum deposited 4,4',4''-tris(N-(1-naphthyl)-N-phenylamino)-triphenylamine (1-TNATA), a widely-used semiconductor material, is placed as a thin interlayer between indium tin oxide (ITO) electrode and a hole transporting layer (HTL) in OLEDs and a well-stacked 1-TNATA layer leads to stable and high efficiency devices by reducing the carrier injection barrier at the interface between the ITO anode and hole transport layers. According to Raman spectra, thermal annealing after deposition as well as electromagnetic field treatment during deposition lead to closer stacking of 1-TNATA molecules and resulted in molecular ordering. By thermal annealing at about $110^{\circ}C$, an increase in current flow through the film by over 25% was observed. Molecularly-ordered 1-TNATA films played an important role in achieving higher luminance efficiency as well as higher power efficiency of the multi-layered organic EL devices in the present work. Electromagnetic field treatment during deposition was less effective compared to thermal annealing

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.79-88
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• 2001

Lectin was isolated from shiitake mushroom (Lentinula edodes) with 0.15 M NaCl solution, and purified by the following procedures : precipitation by ammonium sulfate, anion exchange column chromatography on DEAE Sephadex A-50 and hydroxyapatite column chromatography. The fresh pileus part of the mushroom contained more than two times of lectin compared to the stipe part, and lectins and its activity were reduced by heating. The extraction yield of crude lectin was 46.03%, 28% yield after purification on on DEAE Sephadex A-50 column chromatography. Some amino acids, aspartic acid, serine, alanine and histidine, were increased by purification process. Relatively low molecular weight parts of lectin had the agglutinating activity for rabbit blood, and its molecular weight was about 23 kDa The molecular weights of purified lectins, LA-a and LB-b, by the hydroxyapatite column chromatography were 24 kDa and 23 kDa, respectively.

• Applied Biological Chemistry
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• v.35 no.2
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• pp.92-98
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• 1992

Some physicochemical properties and molecular structure of cow pea, mung bean and acorn starches(mook-forming starches) and red bean, wheat and sweat potato starches(mook-unforming starches) were investigated. Amylose contents of cow pea, mung bean and acorn starch were higher than the others. Cow pea starch was similiar to mung bean starch in gelatinization characteristics by Brabender amylogram but cold viscosity of red bean starch and peak viscosity of sweet potato starch were especially high. Whereas viscosity of wheat starch was low in whole temperature range. Amylose molecules of larger molecular size$(above\;5{\times}10^5\;molecular\;weight)$ of three mook-forming starches were more than shoes of red bean and wheat starch. Chain distribution ratios$(DP\;35{\sim}55\;to\;DP\;10{\sim}20)$ of cow pea, mung bean and acorn amylopectin were higher than thoes of red bean, sweet potato and wheat amylopectin.

• IMMUNE NETWORK
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• v.2 no.1
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• pp.35-40
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• 2002

Background: CTLA-4 (Cytotoxic T Lymphocyte associated Antigen 4, CD152) has been known as a homologue of CD28, an accessory molecule providing a key costimulatory signal for successful antigen-driven activations of T lymphocyte. Most of biochemical and cell biological characteristics of the CD152 protein remain unknown while those of CD28 have been characterized in detail. Methods: In this study CD152 expression in both $CD4^+$ and $CD8^+$ PBLs was studied by using flow cytometry. And intracellular CD152 multiprotein complex was purified and used for generating antibodies recognizing proteins composing of intracellular CTLA-4 multi protein complex. Results: Level of surface expression of this molecule was peaked at 2 days of PHA stimulation in flow cytometric analysis. 40~45% of PHA blast cells were $CD152^+$ in both of two subsets at this stage and the level of expression were equivalent in both two subsets. Contrary to this surface expression, intracellular expression was peaked at day 3 and it was preferentially induced in $CD8^+$ cells and about 60% of $CD8^+$ cells were $CD152^+$ at this stage. High molecular weight (>350 kD) intacellular CD152 protein complex purified by using preparative electrophoresis were immunized into rabbits and then 3 different anti-P34PC4, anti-P34PC7 and anti-P34PC8 antibodies were obtained. Using these 3 antibodies two unknown antigens associated with intracellular CD152 multiprotein complex were found and their molecular weights were 54 kD and 75 kD, respectively. Among these, the former was present as 110 kD homodimer in non-reducing condition. Conclusion: It seemed that 34 kD intracellular CD152 molecule forms high molecular weight multiprotein complex at least with 2 proteins of 75 kD monomer and 110 kD homodimer.

• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.283-290
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• 2002

Generally polymer mortar and concrete using unsaturated polyester resin has high strengths and good chemical resistance. However it also has high brittleness and because of this reason, it is not used for the purpose that demands high resistance to impact. The purpose of this study is to improve the brittleness of unsaturated polyester mortar(UPE mortar) which could be used for the flooring material with recycled aggregates and UPE. Polyurethane liquid rubber(PU) and recycled aggregates were used to complement the brittleness and to recycle the resources respectively. The characteristics of mortar were investigated according to the molecular weight and substitution rate of PU. As the molecular weight and PU substitution rate were increased, the viscosity was increased, working life became fast and curing shrinkage was reduced. Compressive and flexural strengths were also reduced but tile brittleness was improved. Therefore, it is seemed that the improved WE mortar could be obtained by using polyurethane liquid rubber with the polyol of molecular weight 2000, 3000.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.112-117
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• 2016

This research compared the tensile performance of the vegetation mat, which was developed byu using the rapidly growing biodegradable plastic, Poly Lactic Acid(PLA), according to the biodegradation period. The test applied the method defined by Korean Standard KS. In the result of experiment using single-material PLA mesh and PLA plastic, the tensile strength and molecular weight were inverse-proportional to the 5 months of biodegradation period. The thickness of PLA mesh was increased by 11.2~13.4% while the tensile strenth of it was reduced by 32.4~55.4%. The tensile strength and molecular weight of PLA plastic were also reduced over time. However, the tension test of vegetation mat comprised of PLA mesh, non-woven fabric (including seeds), and jute net didn't have specific tendency.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.243-252
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• 2006

White salted noodles and pan bread were prepared from Korean wheats with 1Dx2.2+1Dy12 subunits in high molecular weight glutenin subunits (HMW-GS) to evaluate the suitability for end-use products through the comparison with US wheats with various classes and commercial wheat flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed higher SDS sedimentation volume than US wheat flours with similar protein content. Compared to wheat flours with similar protein content and SDS sedimentation volume, water absorption percent of Korean wheat flours using a mixograph was higher than that of US wheat flours, but similar to commercial wheat flours. Mixograph mixing time was similar to hard wheat flours and commercial noodle flours. Optimum water absorption percent of noodle dough from Korean wheat flours was higher than that of US wheat flours. Noodle sheets from Korean wheat flours with 1Dx2.2+ 1Dy12 subunits showed lower L values, higher a values and similar b values compared to commercial noodle flours. Hardness of cooked noodles from Korean wheat flours 1Dx2.2+1Dy12 subunits correlated positively with protein content, NIRS hardness, mixograph water absorption and gluten yield of flours. Korean wheat flours with 1Dx2.2+1Dy12 subunits showed lower loaf volume and harder crumb firmness than hard wheat flours and commercial bread wheat flours in spite of similar protein quantity and quality to hard wheat flours.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.610-613
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• 2009

New rod-disc liquid crystal (LC) molecule RD12 (12 is the number of carbon atoms between the rod and disc mesogenic liquid crystals) was synthesized via the chemical attachment of six cyanobiphenly calamitic mesogens linked to the triphenyl discotic mesogen with six alkyl chain linkage. Aligning characteristics associated with homogenous alignment is investigated at first and then field-dependent molecular reorientation under a vertical electric field is studied. Interestingly, they show abnormal slow molecular transition from initiate state (no electric field condition) to certain voltage. In this condition, we observe the molecular competition during reorientation. However, once a tilting direction of disk molecules are defined, the frustration is not observed anymore. The origin of this phenomenon is explained with a suggested model for the first time.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.1
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• pp.10-23
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• 2007

Hallmarks of clinical behaviors of adenoid cystic carcinoma(ACC) of salivary glands are the delayed onset of vascular metastasis and poor responses to classical chemotherapeutic agents. Poor prognoses from salivary ACC are caused by lung metastases that are resistant to conventional therapy. Therefore, cellular and molecular characteristics that influence the dissemination of metastatic cells are important for the design of more effective treatment of salivary ACC. Tumor angiogenesis has been known to be essential for the distant metastasis of malignant cells. So, we determined expressions of angiogenic proteins in benign (pleomorphic adenoma) and malignant (ACC, mucoepidermoid carcinoma) tumors of salivary glands and compared each other and to those in oral squamous cell carcinoma. Using surgical specimens, we performed immunohistochemical assays with anti-vascular endothelial growth factor (VEGF), VEGF receptor-2 (VEGFR-2), phosphorylated VEGFR-2 (pVEGFR-2), matrix metalloproteinase (MMP)-9, and interleukin (IL)-8 antibodies. Most angiogenic factors were overexpressed in malignant salivary tumors than in pleomorphic adenoma which is benign nature. Moreover, ACC demonstrated more expression of VEGFR-2 than that of squamous cell carcinoma which used as control. Conclusively, these data show those angiogenic factors produced by salivary gland tumors may affect the propagation and metastasis of malignant cells of salivary tumors, and could be used as biomarkers for the malignant transformation of salivary gland tumors. Prospectively, although further studies will be needed, these biomarkers related to angiogenesis can be molecular targets for the therapy of salivary ACC, which has propensity for delayed vascular metastasis.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2238-2246
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• 2012

Molecular dynamics simulations have been performed to investigate hydrogen bonding characteristics of hydroxyl groups in glucose aqueous solutions with different concentrations. The hydrogen bonding abilities and strength of different O and H atom types have been calculated and compared. The acceptor/donor efficiencies have been predicted and it has been found that: (1) O2-HO2 and O3-HO3 are more efficient intramolecular hydrogen bonding acceptors than donors; (2) O1-HO1, O4-HO4 and O6-HO6 are more efficient intramolecular hydrogen bonding donors than acceptors; (5) O1-HO1 and O6-HO6 are more efficient intermolecular hydrogen bonding acceptors than donors while hydroxyl groups O2-HO2 and O4-HO4 are more efficient intermolecular hydrogen bonding donors than acceptors. The hydrogen bonding abilities of hydroxyl groups revealed that: (1) the hydrogen bonding ability of OH2-$H_w$ is larger than that of hydroxyl groups in glucose; (2) among the hydroxyl groups in glucose, the hydrogen bonding ability of O6-HO6 is the largest and the hydrogen bonding ability of O4-HO4 is the smallest; (3) the intermolecular hydrogen bonding ability of O6-HO6 is the largest; (4) the order for intramolecular hydrogen bonding abilities (from large to small) is O2-HO2, O1-HO1, O3-HO3, O6-HO6 and O4-HO4.