• International Journal of Advanced Culture Technology
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• v.3 no.2
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• pp.25-33
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• 2015

This study aims to synthesis the self-cleaning fibers. The nano-titanium dioxide ($TiO_2$) were blend with the polypropylene (grade 561R) at 1wt%, 3wt%, 5wt%, 10wt%, 15wt% and 20wt%. The $TiO_2$-fibers were obtained from single screw extruder. The mechanical, thermal, rheology and self-cleaning properties were also investigated. The results showed that the tensile strength of the $nTiO_2$-PP fibers decreased with increasing of the amount of $TiO_2$. The presents of the $TiO_2$ in the PP fibers significantly showed the improving of the self-cleaning properties under sunlight and 20 watt of UV radiation. The $TiO_2$-PP fibers in presents of $TiO_2$ 20wt% showed the best results of self-cleaning under 5 hours of the sunlight which the similar results were found under 5 hours of 20 watts of UV radiation.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.943-946
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• 2011

The electronic absorption and surface morphology evolution of two types of molecular double layer thin films, copper phthalocyanine (CuPc) layer deposited on chloro[subphthalocyaninato]boron(III) (SubPc) layer, denoted as SubPc/CuPc, and vice versa, with various thicknesses were investigated using ultraviolet (UV)-visible spectroscopy and atomic force microscopy (AFM). Both types of double layer structures showed similar broadened absorption patterns in the UV-visible region that were consistent with the fitted spectra following simple linear combination of the single layer absorption spectra of the two materials. In contrast, the surface morphology of double layer structures was dependent on the order of deposition. For the CuPc/SubPc structures, surface morphology was characterized by elongated grains, which are characteristic of SubPc thin films, indicating that the morphological influence of the underlying CuPc layer on the subsequent SubPc layer was not large. For the SubPc/CuPc structures, however, the underlying SubPc layer acted as a morphological template for the subsequently deposited CuPc layer. It was also observed that the grain size of the CuPc layer varied according to the thickness of the underlying SubPc layer.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1733-1737
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• 2009

A new cathode material based on Li$Ni_{0.8}Co_{0.15}Al_{0.05}O_2$ (LNCA)/polyaniline (Pani) composite was prepared by in situ self-stabilized dispersion polymerization in the presence of LNCA. The materials were characterized by fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Electrochemical properties including galvanostatic charge-discharge ability, cyclic voltammetry (CV), capacity, cycling performance, and AC impedance were measured. The synthesized LNCA/Pani had a similar particle size to LNCA and exhibited good electrochemical properties at a high C rate. Pani (the emeraldine salt form) interacts with metal-oxide particles to generate good connectivity. This material shows good reversibility for Li insertion in discharge cycles when used as the electrode of lithium ion batteries. Therefore, the Pani coating is beneficial for stabilizing the structure and reducing the resistance of the LNCA. In particular, the LNCA/Pani material has advantageous electrochemical properties.

• Composites Research
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• v.26 no.2
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• pp.135-140
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• 2013

The static test was performed to verify the effect of the joint in the UHPC bridge deck slab and the minimum lap-spliced length was presented. A total of six test members was fabricated to estimate the static behavior of the steam curing UHPC bridge deck slab joint by the four points bending test method. The lap-spliced joint type was expected to be not only simple but also efficient in UHPC structure because of the high bond stress of UHPC. Test results show that the decrease of maximum flexural strength was about 30% and the minimum lap-spliced length which behaved similar to the continued reinforcement in strength and ductility was 150 mm.

• Journal of Korean Biological Nursing Science
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• v.22 no.1
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• pp.36-44
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• 2020

Purpose: The purpose of this study was to predict measuring site suited for abdominal skin fold thickness (ASFT) by measuring the distribution of abdominal subcutaneous fat thickness (AScFT) and ascertain the correlations among obesity indicators. Methods: The size of analysis materials was 124 secondary data measured by ultrasonic device, bioelectrical impedance analyzer and caliper. Data were analyzed using t-test, and Pearson's correlation. Results: The average of AScFT was 10.63± 6.79mm with its range 1.39-36.16 mm, and AScFT of female and of central parts were thicker than those of male and outer parts in the abdomen. The average of ASFT was 29.26±12.59 mm. Site 5 on Figure 1 was most similar to the average of AScFT in both sexes. Body mass index (BMI) and waist hip ratio (WHR) were 23.65±3.98 and 0.88±0.05 respectively. The body weight, BMI, WHR, visceral fat, ASFT vs AScFT revealed in significant correlation (r= .29, r= .55, r= .39, r= .33. r= .29). Conclusion: BMI and WHR seem more useful than other obesity indicators, when obesity control is necessary for Type 2 diabetes patients. Site 5 on Figure 1 is most suitable site to measure ASFT.

• The Korean Journal of Ecology
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• v.18 no.1
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• pp.137-146
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• 1995

Acer pseudo-sieboldianum, A. ginnala, A. negundo and A. saccharinum were selected as materials for the studies on the seasonal fluctuation of chlorophyll content and photosynthetic rates. In all the four species during the growing season except in October, the principal component that determined the total chlorophyll content was chlorophyll a. Content of chlorophyll b increased with leaf age, but that of chlorophyll a decreased. In contrast to A. saccharinum and A. pseudo-sieboldianum which showed their maximum chlorophyll content in June, A. negundo, which showed the highest chlorophyll content of the four species, exhibited its maximum chlorophyll content in July, whereas September in the case of A. ginnala. The fluctuation of chlorophyll content was similar to that of air temperature, and it increased till July. But chloprophyll content showed a significant relationship in early stage of leaf development, and there could be any interdependence between them in accordance with the seasonal change, no longer. In all four species light compensation points decreased in accordance with the seasonal change, and the maximum photosynthetic rates were obtained in August. Respiratory rates were shown no significant difference among species, and they decreased according to the adbance of season.

• Journal of Electrochemical Science and Technology
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• v.1 no.1
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• pp.45-49
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• 2010

$Li_2PtO_3$ thin film electrodes, which might be possible candidate for the cathode materials for implantable batteries, were synthesized using an electrostatic spray deposition (ESD) technique onto a platinum foil substrate. Single phase $Li_2PtO_3$with a structure similar to layered $LiCoO_2$ structure were synthesized by spraying a precursor solution of $CH_3CO_2Li2H_2O$ in ethanol onto a Pt substrate at temperatures ranging from 200 to $400^{\circ}C$ followed by annealing at above $600^{\circ}C$. Lithium carbonate was the only major phase at temperatures up to $500^{\circ}C$. The X-ray diffraction (XRD) peaks of the Pt foil substrate and lithium carbonate disappeared at temperatures >$600^{\circ}C$. The volumetric capacity of the $Li_2PtO_3$ thin film synthesized using the ESD technique was approximately 817 mAh/$cm^3$, which exceeded that of $LiCoO_2$ (711 mAh/$cm^3$).

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.42 no.1
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• pp.9-12
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• 2016

Objectives: In this study we evaluated heat generation during the low-speed drilling procedure without irrigation. Materials and Methods: Ten artificial bone blocks that were similar to human D1 bone were used in this study. The baseline temperature was $37.0^{\circ}C$. We drilled into 5 artificial bone blocks 60 times at the speed of 50 rpm without irrigation. As a control group, we drilled into an additional 5 artificial bone blocks 60 times at the speed of 1,500 rpm with irrigation. The temperature changes during diameter 2 mm drilling were measured using thermocouples. Results: The mean maximum temperatures during drilling were $40.9^{\circ}C$ in the test group and $39.7^{\circ}C$ in the control group. Even though a statistically significant difference existed between the two groups, the low-speed drilling did not produce overheating. Conclusion: These findings suggest that low-speed drilling without irrigation may not lead to overheating during drilling.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.4
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• pp.191-197
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• 2018

Objectives: The objective of the study was to evaluate the results of nasolabial/extended nasolabial flaps as a modality for treatment of oral submucous fibrosis. Materials and Methods: Eleven patients of Stage III or IVa maximum interincisal opening were selected to be operated. Nasolabial/extended nasolabial flaps were done for both the sides. All of the flaps were done in a single stage and were inferiorly based. A similar flap harvest/surgical technique was utilized for all the cases. Results: The preoperative mouth opening ranged from 5 to 16 mm, with a mean of 10.09 mm. At 6 months the mouth opening ranged from 29 to 39 mm. Some of the complications encountered were poor scar, wisdom tooth traumatising the flap, decreased mouth opening due to non compliance and too much bulk. All of theses were managed satisfactorily. Conclusion: The nasolabial flap is a very reliable flap to restore the function of oral cavity. Important adjuvant measures are habit cessation, lifestyle changes, and aggressive physiotherapy.

• Journal of Periodontal and Implant Science
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• v.38 no.1
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• pp.109-113
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• 2008

Purpose: Surgical intervention into the maxillary posterior area can lead to inadvertent communication with the maxillary sinus. Spontaneous healing of 1 to 2 mm openings can occur. However, in patients with larger oro-antral communications and those with a history of sinus disease, surgical closure is often indicated. Materials and Methods: In this case, a modified free gingival graft technique was used. The oro-antral sinus track after extraction was about $2{\times}4\;mm$. But the patient had a history of Caldwell-Luc operation. Immediately after extraction, a modified free gingival graft was used for the closure of oro-antral sinus track. Result: A modified free gingival graft technique was successfully used for the closure of oro-antral sinus track. With this technique, esthetic results including similar colors, textures were achieved. Conclusion: It is thought that this technique is very useful in the closure of oro-antral sinus track.