• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.43-49
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• 2023

This study reports on the preparation of sodium caseinate-cardanol (CasNa/CL)-based papers coated with different amounts of bentonite (BN) for use as a sustainable packaging material. Their chemical and morphological structures, mechanical properties, water vapor permeability, surface properties, and antioxidant activity of coated papers was assessed as a function of the BN content. The drying of the CasNa/CL coated papers led to the formation of pinholes on their surfaces owing to the presence of trapped water resulting from the difference in the drying rate between the external surface and the inside of the coated layers. Increasing the BN content reduced the pinholes on surface of CasNa/CL/BN coated papers and highly decreased the water vapor transmittance rate of the papers from 387.3±1.9 g/m²·day to 269.25±4.5 g/m²·day. Free radical scavenging assays indicated the addition of CL to the CasNa exhibited the antioxidant activity and antioxidant activity of CasNa/CL/BN did not changed as increase of BN contents. The improved water vapor barrier property and antioxidant activity of CasNa/CL/BN coated papers can be promised for various packaging applications.

• Current Research on Agriculture and Life Sciences
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• v.28
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• pp.69-78
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• 2010

To develop the functional noodles, powders of soybean and Gastrodine rhisoma were mixed with wheat powder. When 0-5% of soybean powder was mixed with wheat one, the characteristics of noodles was changed as follows; Along with the increasing of mixed soybean powder, L(brightness) and a(redness) value was decreased. Hardness showed increasement in all noodles added with soybean powder but, on the contrary, Cohesiveness was decreased. The content of isoflavones in noodles was increased along with the increament of mixing ratio of soybean powder. Sensory evaluation showed that the noodles with 5% of sobyean powder was significanly higher than those of no-soybean powder. At the same time, the characteristics of noodles added with Gastrodine rhisoma was evaluated. The results were as follows; As in soybean powder, L(brightness) and a(redness) value was decreased along with the increasing of mixed Gastrodine rhisoma. Compared with no-powder, hardness and Chewiness was significantly increased in 0.5% and 1.0% in soybean powder, and 0.5% in Gastrodine rhisoma one, respectively. Sensory evaluation showed that the noodles with 1.0% of Gastrodine rhisoma powder was significanly higher than those of no-soybean powder. Considering together with sensory evaluation and economic aspect, noodles with 5% of soybean powder and 0.5% of Gastrodine rhisoma to be the best ones.

• The korean journal of orthodontics
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• v.25 no.2 s.49
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• pp.187-200
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• 1995

To estimate the characteristics of Korean Ni-Ti alloy orthodontic wire, this study investigated compositions, tensile properties, bending properties, heat treatment effects, and ion releasing degrees, and compared these characteristics to those of the imported Ni-Ti alloy wire. The results obtained are as follows ; 1. Ti and -Ni elements in ORTHOLLOY were in a range showing superelasticity, and there was a little difference in the Ni and Ti contents of ORTHOLLOY as compared with those of SENTALLOY. 2. The results of the tensile test concerning ORTHOLLOY exhibited a superelastic effect, indicating an area of a definite amount of stress in spite of the changes in the range from $2\%\;to\;8\%$ in the strain rate. 3. ORTHOLLOY presented higher load values than SENTALLOY in the same deflection values when the wire was tested in three-point bending. A load range displaying a superelastic effect was 80-l00g, 140-l80g, and 130-200g respectively, in wire diameters of 0.014', 0.016', and 0.018' 4. By heat treatments at $400^{\circ}C$ and at $500^{\circ}C$, a load range showing the effect of superelasticitly was lessened by the duration of the heat treatment time. The superelastic effect was destroyed as a result of the 10 minutes heat treatment at $600^{\circ}C$. 5. The quantity of the Ni ion released from ORTHOLLOY, tended to be greater than the amount of released Ni ion in SENTALLOY. The Co ion released was very little(<0.01ppm) in SENTALLOY and ORTHOLLOY irrespective of the lapse of time. Released Ni ions on the 1st day were at the maximum, and the releasing rate showed plateaus after three days. 6. The surface morphology of SENTALLOY was relatively regular irrespective of the lapse of rime, and the corrosion tendency was not observed. However, the surface morphology of ORTHOLLOY was rather irregular and shelved fitting corrosion after immersion.

• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.73-90
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• 2014

The Officially Announced Land Price System has a limit, that is required to be able to reflect changes in land constantly every year, to implement Land Characteristic Survey for calculating land price during a specific period and human resources with limited. The purpose of this study is to apply the 'National Territory Space Usage status Survey' method to survey part of the territorial feature status information inside of selected the target sites, considering the core survey items (land category, the state of land use, altitude difference, standard site inclusion, etc) in the areas surrounding Yeonshinnae Station in which three dongs (Galhyeon-dong, Daejo-dong, Bulgwang-dong) of Eunpyeong-gu, Seoul share borders with. Based on the given budget, the manpower and period was taken into consideration to sort a total of 2,041 lots and conduct surveys on all sites. This study will be able to diagnose the efficient idle human resource utilization and work process construction plan through pilot projects specialized for providing real estate information services in preparation for cases in which national territory information survey projects that provide various business model, as well as major future core projects of the corporation will be carried out.

• Korean Journal of Food Science and Technology
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• v.54 no.3
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• pp.327-333
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• 2022

An orally disintegrating film (ODF) based on hyaluronic acid (HA) containing vitamin D was developed. The vitamin D content in the ODF was set based on the adequate intake (AI) of vitamin D from 0 to 10 AI (0, 1, 4, 7, and 10AI). The control (0AI) had the highest thickness and showed the longest disintegration time among the samples. The moisture content of the ODFs was significantly lower in those with vitamin D compared to the control. As the amount of vitamin D increased, the water vapor permeability (WVP) of the ODFs decreased, and the opacity significantly increased. The tensile strength was higher in the films containing vitamin D compared to the control films. However, the elongation at the break showed no significant difference among the films. The vitamin D content in the film was reduced by 25.7-44.2% during processing compared to the amount that was originally added. Based on the above results, a new and convenient vitamin D delivery system, an ODF, could be successfully produced.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.954-959
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• 1999

Radiation-induced grafting of 2-hydroxyethyl methacrylate(HEMA), acrylic acid(AAc) and methacrylic acid(MAAc) onto polypropylene microfiltration membrane has been studied. The effect of grafting conditions such as solvent composition(MeOH and $H_2O$) and monomer concentration on the grafting yield in investigated. The highest degree of grafting is obtained at a solvent composition of 25% $H_2O$:75% MeOH for HEMA, pure water for AAc and 50% $H_2O$:50% MeOH for MAAc. Modification of the PP membranes with hydrophilic monomers is shown to cause an increase in the water permeation flux of the membranes. It is found that HEMA is the best monomer to increase the water permeation flux and the highest water permeation flux is obtained at 99% degree of grafting. The water permeation flux of AAc-grafted PP membrane and MAAc-grafted PP membrane is very sensitive to environmental pH and $Cu^{2+}$ ion, but the water permeation flux of HEMA-grafted PP membrane scarcely depends on pH and $Cu^{2+}$ ion.

• Polymer(Korea)
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• v.35 no.4
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• pp.337-341
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• 2011

To expand the viewing angle of vertical alignment liquid crystal display (VA-LCD), a wide-band compensation film has been newly developed. VA-LCD needs a retardation film with improved oblique viewing property. The retardation film for VA-LCD has been fabricated by solvent casting and subsequent drawing triacetylcellulose (TAC) containing optical additives. Here, optical birefringence and wavelength dispersion of the retardation film strongly depend on the chemical structures of optical additives. Utilizing quantum mechanical computation, the polarizing anisotropy of retardation film was calculated with respect to additives. It is also realized that the wavelength dispersion of polarizing anisotropy depends on the type and location of substituent to the selected main isomer. When two propionates are substituted to the meta position of the selected main isomer, the wavelength dispersion of polarizing anisotropy shows the most gentle slop, which is well matched with the experimental results. The most gentle slop of wavelength dispersion means that the viewing angle characteristics of LCD are less influenced according to the wavelength of light source of LCD, and it's possible to make better image quality than the present level.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.99-105
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• 2002

To develop good soybean varieties for sprouts. 285 indigenous lines and 16 recommending varieties were evaluated by the sprout and agronomic characteristics. The range of whole length, hypocotyl length, root length, and yield rate of sprouts was 9.5~23.0cm, 5.9~15.1cm, 3.2~9.2cm, and 121~695%, respectively. Yield rate of sprouts was the highest, 409%, in the lines of mixed seed coat color. At the same time, it was reversely proportional to seed weight : the smaller the seed weight, the higher the yield rate as in all other reports. The number of roots was significantly fewer in the lines of the black and the green seed coat color than others. Based on whole length, rate of root length, and yield rate of sprouts, many indigenous lines were evaluated much better than recommending varieties. In the hypocotyl color of sprouts, the brightness was higher in improved variety than indigenous lines but vice versa in redness and yellowness in general.

• Journal of Korea Foundry Society
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• v.41 no.5
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• pp.434-444
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• 2021

This study investigated the overall dependence of the tensile properties of Al-Si alloys on the distribution aspect of a eutectic Si particle in terms of defect susceptibility to the effective void area fraction, referring to the sum of pre-existing microvoids and the damage evolution of the Si particle. The network morphology of as-cast Al-xSi (x=2,5,8,11) alloys was modified to a granular type via a T4 treatment, after which a computational topography (CT) analysis and scanning electron microscope (SEM) observations were utilized to evaluate the size and distribution of the microvoids. The CT and SEM analyses indicated that the main cracks grow along local regions that possess the highest porosity level. The local plastic deformation around the microvoids and the distribution aspect of the microvoids induced a practical difference between the iso-volumetric CT measurement and the SEM fractography outcomes. The results demonstrated that the overall dependence of the ultimate tensile strength (UTS) and elongation on the effective void area fraction is more sensitive to the variation of the area fraction of the Si particle in the network morphology than in the granular type; this is due to the sequential damage evolution of the neighboring Si particles in the eutectic Si colony.

• Composites Research
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• v.35 no.3
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• pp.147-152
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• 2022

Low-temperature characteristics according to internal temperature conditions during rotational molding of Type 4 pressure vessel liners were studied in this paper. Since rotational molding has a sensitive effect on the formability of the liner depending on the temperature conditions, the temperature conditions for the polyamide used should be accurately set. The structural changes of polyamide as the liner material was analyzed the surface by atomic force microscope (AFM), and the crystallinity measured with a differential scanning calorimeter (DSC) is used to evaluate the change of the mechanical strength value at low temperature. In addition, the formability of the liner was confirmed by observation of the yellow index inside the liner. As a result, as the melting range of the internal temperature becomes wider, the yellow index shows a lower value, and the elongation and impact characteristics at low temperatures are improved. It was also confirmed that the structure of the polyamide was uniform and the crystallinity was high by AFM and DSC. These experimental results contribute to the improvement of characteristics at low temperatures due to changes in temperature conditions during rotational molding.