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A Study on the Improvement of Skin-affinity and Spreadability in the Pressed Powder using Air Jet Mill Process and Mono-dispersed PMMA (Air Jet Mill 공법과 PMMA의 단분산성이 프레스드 파우더의 밀착성 및 발림성 향상에 대한 연구)

  • Song, Sang Hoon;Hong, Kyong Woo;Han, Jong Seob;Kim, Kyong Seob;Park, Sun Gyoo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.43 no.1
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    • pp.61-68
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    • 2017
  • The key quality attributes of the pressed powder, one of base makeup products, are skin-affinity and spreadability. In general, there was a limit to meet skin-affinity and spreadability simultaneously, which are opposite attributes each other. In this study, air jet mill process was tried to satisfy two main properties. Skin-affinity was improved by a wet coating of sericite with a mixture of lauroyl lysine (LL) and sodium cocoyl glutamate (SCG). The application of mono-dispersed polymethyl methacrylate (PMMA) and diphenyl dimethicone/vinyl diphenyl dimethicone/silsesquioxane crosspolymer (DDVDDSC) improved both qualities. Air jet mill process has been mainly applied in the pharmaceutical and food industries, and is a method used for processing powder materials in cosmetic field. In this study, we were able to complete makeup cosmetics with an optimum particle size $6.8{\mu}m$ by combining the air jet mill process at the manufacturing stage. It was confirmed that the Ti element was uniformly distributed throughout the cosmetics by EDS mapping, and that the corners of the tabular grains were rounded by SEM analysis. It is considered that this can provide an effect of improving the spreadability when the cosmetic is applied to the skin by using a makeup tool. LL with excellent skin compatibility and SCG derived from coconut with little skin irritation were wet coated to further enhance the adhesion of sericite. SEM images were analyzed to evaluate effect of the dispersion and uniformity of PMMA on spreadability. With the spherical shapes of similar size, it was found that the spreading effect was further increased when the distribution was homogeneously mono-dispersed. The dispersion and spreadability of PMMA were confirmed by measuring the kinetic friction and optimal content was determined. The silicone rubber powder, DDVDDSC, was confirmed by evaluating the hardness, spreading value, and drop test. Finally, it was found that the dispersion of PMMA and silicone rubber powder affected spreadability. Such makeup cosmetics have excellent stability in drop test while having appropriate hardness, and good stability over time. Taken together, it is concluded that air jet mill process can be utilized as a method to improve skin-affinity and spreadability of the pressed powder.

The Simulation of Pore Size Distribution from Unsaturated Hydraulic Conductivity Data Using the Hydraulic Functions (토양 수리학적 함수를 이용한 불포화 수리전도도로부터 공극크기분포의 모사)

  • Yoon, Young-Man;Kim, Jeong-Gyu;Shin, Kook-Sik
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.407-414
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    • 2010
  • Until now, the pore size distribution, PSD, of soil profile has been calculated from soil moisture characteristic data by water release method or mercury porosimetry using the capillary rise equation. But the current methods are often difficult to use and time consuming. Thus, in this work, theoretical framework for an easy and fast technique was suggested to estimate the PSD from unsaturated hydraulic conductivity data in an undisturbed field soil profile. In this study, unsaturated hydraulic conductivity data were collected and simulated by the variation of soil parameters in the given boundary conditions (Brooks and Corey soil parameters, ${\alpha}_{BC}=1-5L^{-1}$, b = 1 - 10; van Genuchten soil parameters, ${\alpha}_{VG}=0.001-1.0L^{-1}$, m = 0.1 - 0.9). Then, $K_s$ (1.0 cm $h^{-1})$ was used as the fixed input parameter for the simulation of each models. The PSDs were estimated from the collected K(h) data by model simulation. In the simulation of Brooks-Corey parameter, the saturated hydraulic conductivity, $K_s$, played a role of scaling factor for unsaturated hydraulic conductivity, K(h) Changes of parameter b explained the shape of PSD curve of soil intimately, and a ${\alpha}_{BC}$ affected on the sensitivity of PSD curve. In the case of van Genuchten model, $K_s$ and ${\alpha}_{VG}$ played the role of scaling factor for a vertical axis and a horizontal axis, respectively. Parameter m described the shape of PSD curve and K(h) systematically. This study suggests that the new theoretical technique can be applied to the in situ prediction of PSD in undisturbed field soil.

SEM Photomicrograph on Fluoride Concentration of Enamel by Fluoride Iontophoresis (불소이온영동에 의한 법랑질 표면 불소농도의 주사전자현미경적 관찰)

  • Jang, Jong-Hwa;Lee, Young-Soo
    • Journal of dental hygiene science
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    • v.6 no.4
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    • pp.303-307
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    • 2006
  • The objective of this study was to evaluate the effects of the topical application of fluoride by iontophoresis on the fluoride concentration in the dental enamel. Eighty-eight healthy teeth were extracted from orthodontic patients and divided into three experimental groups at 0.2 mA and 0.5 mA current and a control group. Each experimental group was further divided into three subgroups according to the application time (1, 3, and 5 min). Five to six teeth were assigned to each subgroup. Inotophoresis was performed using a 2% sodium fluoride solution and each tooth was sliced into a $3{\times}3mm$ specimen on enamel. The fluoride concentration in the enamel was measured using X-ray photoelectron spectroscopy. It was used to estimate the atomic ratio of fluoride on the enamel surface on selected samples. The specimen was observed via scanning electron microscopy as well. This finding was confirmed by the result that the fluoride ratios estimated by x-ray photoelectron spectroscopy was 2.71%, 2.87% and 3.80% after fluoride iontophoresis had been performed using a 2% sodium fluoride solution at 0.5 mA for 1, 3 and 5 min, respectively. In comparison, the fluoride ratio was 0.49% in the control group. As the current became higher and the time lapsed, the formation of irregular particles was strengthened on the enamel surface. Afterwards, the enamel surface was dissolved and new matrix was formed on the enamel. Fluorapatite was observed on the enamel after fluoride iontophoresis was performed at 0.5 mA for 5 min. The fluoride concentration tended to increase with increasing duration of iontophoresis. The study findings indicated that under proper conditions, fluoride iontophoresis has a positive effect in increasing the fluoride concentration in dental enamel.

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The Density and Strength Properties of Lightweight Foamed Concrete Using Stone-Powder Sludge in Hydrothermal Reaction Condition (수열반응 조건에서 석분 슬러지를 사용한 경량 기포 콘크리트의 밀도와 강도 특성)

  • Kim, Jin-Man;Jeong, Ji-Yong;Choi, Se-Jin;Kim, Bong-Joo
    • Journal of the Korea Concrete Institute
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    • v.18 no.5 s.95
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    • pp.687-693
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    • 2006
  • The Stone Powder Sludge(below SPS) is the by-product from the process that translates stone power of 8mm under as crushed fine aggregate. It is the sludge as like cake that has average particle size of $7{\mu}m$, absorbing water content of 20 to 60%, and $SiO_2$ content of 60% over. Because of high water content of SPS, it is not only difficult to handle, transport, and recycle, but also makes worse the economical efficiency due to high energy consuming to drying. This study is aim to recycle SPS as it is without drying. Target product is the lightweight foamed concrete that is made from the slurry mixed with pulverized mineral compounds and foams through hydro-thermal reaction of CaO and $SiO_2$. Although in the commercial lightweight foamed concrete CaO source is the cement and $SiO_2$ source is high purity silica powder with $SiO_2$ of 90%, we tried to use the SPS as $SiO_2$ source. From the experiments with factors such as foam addition rate and replacement proportion of SPS, we find that the lightweight foamed concrete with SPS shows the same trends as the density and strength of lightweight foamed concrete increases according to decrease of foam addition rate. But in the same condition, the lightweight foamed concrete with SPS is superior strength and density to that with high purity silica. This trends is distinguished according to increase of replacement proportion of SPS, also the analysis of XRF shows that the hydro thermal reaction translates SPS to tobermorite. Although SPS has low $SiO_2$ contents, the lightweight foamed concrete with SPS has superior strength and density, because it reacts well with CaO due to extremely fine particles. We conclude that it is possible to replace the high purity silica as SPS in the lightweight foamed concrete experimentally.

Effects of Indoor Greening Method on Temperature, Relative Humidity and Particulate Matter Concentration (실내녹화 방법이 온·습도 및 미세먼지 농도에 미치는 영향)

  • Kwon, Kei-Jung;Park, Bong-Ju
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.4
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    • pp.1-10
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    • 2017
  • This study investigated indoor temperature and humidity control and PM1 and PM10 mitigation effects of a single green wall (Case 1), two green walls (Case 2), and two green walls plus a waterfall (Case 3) in comparison with a control without either a green wall or waterfall. Experiments were conducted in the office of Chungbuk National University from August to September, 2015. Experiments were carried out sequentially in the order of control, Case 1, Case 2, and Case 3. Data collected from August 17 to August 20, 2015 (Experiment 1), and from August 31 to September 3, 2015 (Experiment 2), when outdoor temperature was relatively constant, were analyzed. Plant volume ratios by indoor landscaping of the control, Case 1, Case 2 and Case 3 were 0.0, 0.6, 1.2, and 1.4%, respectively. Compared to the control, average temperatures of Case 1, Case 2 and Case 3 were decreased by 0.3~0.7, 0.7~0.9 and $1.0^{\circ}C$, respectively, and relative humidity was increased by 1.8~8.7, 9.2~14.6 and 14.8~21.9%, respectively. Three hundred minutes after exposure to mosquito repellent incense particles, the ratio of the remaining PM1 of the control, Case 1, Case 2 and Case 3 were 25.0, 22.0%, 21.2%, 17.3%, respectively, in Experiment 1 and 42.3, 28.9, 23.1, and 30.9%, respectively, in Experiment 2. As indoor greening increased the effect of indoor temperature, PM1 and PM10 mitigation were greater, and temperature and humidity were lower. The greater the relative humidity was, the faster PM1 and PM10 mitigation tended to be.

Structural Features of the Glandular Trichomes in Leaves of Carnivorous Drosera anglica Huds. (식충식물 긴잎끈끈이주걱 (Drosera anglica Huds.) 분비모의 구조적 특성)

  • Baek, Kyung-Yeon;Kim, In-Sun
    • Applied Microscopy
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    • v.38 no.1
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    • pp.21-28
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    • 2008
  • Carnivorous plants vary in their unique features of morphology, ultrastructure and biochemical properties by species. Furthermore, prey-capturing mechanism as well as structural and physiological adaptations have been used for grouping various carnivorous species. In Drosera plants, glandular trichomes, which develop in the leaf epidermis, are known to play the most important role during the prey capturing process. The present study examined such trichomes, focusing on the glandular type, in leaves of Drosera anglica using scanning and transmission electron microscopy. Three types of rudimentary glandular trichomes were found to develop within the folded leaf primordia and immature leaf during early development. The first type, stalked glandular trichomes (Type I), occurred on the margin and upper epidermis of the leaf. With maturation, the longest glandular trichomes having lengthy stalks, ca. $2.2{\sim}5.1\;mm$, developed along the margin, while shorter stalked trichomes, ca. up to $200\;{\mu}m$, were found on the inner leaf blade. The shorter ones consisted of a globose head having two layers of secretory cells, parenchyma bell cells and tracheids and a multicellular stalk. The stalks gradually decreased in length in centripetal fashion. The second type, Type II, having ca. $15{\sim}30\;{\mu}m$ short stalks, also developed along the inner blade. Both types secreted mucilage from the secretory cells which had a thin cell wall and cuticle layer. The sessile six-celled glandular trichomes were the third type, Type III, and were $25{\sim}40\;{\mu}m$ in length. They were distributed most commonly throughout the upper and lower epidermis, petiole and even on the stalk surfaces of the first two types of trichomes. The third type was also found to be involved in the active secretion. In prey capturing leaves, all trichome types secreted substances through thin cuticles in the head cell wall, which exhibited relatively loose wall components.

The effect of Silano-pen on the shear bond strength of resin to feldspathic porcelain and zirconia (실라노 펜의 적용이 장석계 도재 및 지르코니아와 레진의 전단결합강도에 미치는 영향)

  • Shin, Myoung-Sik;Lee, Jeong-Yol;Kim, Min-Soo;Shin, Sang-Wan
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.1
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    • pp.1-8
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    • 2014
  • Purpose: The purpose of this study is to evaluate the effect of applying Silano-pen to feldspathic porcelain and zirconia on shear bond strength with composite resin. Materials and methods: Feldspathic porcelain and zirconia specimens were produced into 30 per each 2 mm thick and 12 mm in diameter and their surface was made smooth and even and then embedded in acrylic resin. The specimens were divided into each Group F (Feldspathic porcelain) and Group Z (Zirconia), (1) Hydrofluoric acid etching and silane (F1 & Z1), (2) Silano-pen and silane (F2 & Z2), (3) Hydrofluoric acid etching and Silano-pen, silane (F3 & Z3). After surface conditioning, substrate surfaces of the specimen were examined by SEM. Composite resin cylinders (2 mm high, 3 mm in diameter)were bonded to specimen and shear bond strength between ceramic and composite resin was measured by using universal testing machine. The measured values were statistically analyzed by using two way ANOVA and Tukey's multiple comparison test (${\alpha}=.05$). Results: In the scanning electron micrograph of the treated ceramic surface, Group F2 and F3 appeared the high roughness and Group Z3 appeared the highest density of silica particle. In Feldspathic porcelain, the result of measuring shear bond strength showed that Group F3 was measured to be highest and Group F1 was measured to be lowest but there was no statistical significance among Groups. In zirconia, Group Z3 was measured to be highest and Group Z1 was measured to be lowest and there was statistical significance among Groups (P<.05). Conclusion: In zirconia, applying hydrofluoric acid etching and then Silano-pen and silane is effective for composite resin adhesion.

Stability of $^{188}Re$ Labeled Antibody for Radioimmunotherapy and the Effect of Stabilizing Agents (방사면역치료용 $^{188}Re$ 표지 항체의 안정성과 안정제의 효과)

  • Chang, Young-Soo;Kim, Bo-Kwang;Jeong, Jae-Min;Chung, June-Key;Lee, Seung-Jin;Lee, Dong-Soo;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.36 no.3
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    • pp.195-202
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    • 2002
  • Purpose: For clinical application of beta-emitter labeled antibody, high specific activity is imporiant. Carrier-free $^{188}Re$ from $^{188}W/^{188}Re$ generator is an ideal radionuclide for this purpose. However, low stability of $^{188}Re$ labeled antibody, especially in high specific activity, due to radiolytic decomposition by high energy (2.1 MeV) beta ray was problem. We studied the stability of $^{188}Re$ labeled antibody, and stabilizing effect of several stabilizers. Materials and Methods: Pre-reduced monoclonal antibody (CEA79.4) was labeled with $^{188}Re$ by incubating with generator-eluted $^{188}Re-perrhenate$ in the presence of stannous tartrate for 2 hr at room temperature. Radiochemical purity of each preparation was determined by chromatography. Human serum albumin was added to the labeled antibodies (2%). Stability of $^{188}Re-CEA79.4$ was investigated in the presence of ascorbic acid, ethanol, of Tween 80 as stabilizing agents. Results: Labeling efficiencies were $88{\pm}4%\;(n=12)$. Specific activities of $1.25{\sim}4.77MBq/{\mu}g$ were obtained. If stored after purging with $N_2$, all the preparations were stable for 10 hr. However, stability decreased in the presence of air. Perrhenate and $^{188}Re-tartrate$ was major impurity in declined preparation. colloid-formation was not a significant problem in all cases. Addition of ascorbic acid stabilized the labeled antibodies either under $N_2$ or under air by reducing the formation of perrhenate. Conclusion: High specific activity $^{188}Re$ labeled antibody is unstable, especially, in the presence of oxygen. Addition of ascorbic acid increased the stability.

Monte Carlo Simulation of the Carbon Beam Nozzle for the Biomedical Research Facility in RAON (한국형 중이온 가속기 RAON의 의생물 연구시설 탄소 빔 노즐에 대한 Monte Carlo 시뮬레이션)

  • Bae, Jae-Beom;Cho, Byung-Cheol;Kwak, Jung-Won;Park, Woo-Yoon;Lim, Young-Kyung;Chung, Hyun-Tai
    • Progress in Medical Physics
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    • v.26 no.1
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    • pp.12-17
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    • 2015
  • The purpose of the Monte Carlo simulation study was to provide the optimized nozzle design to satisfy the beam conditions for biomedical researches in the Korean heavy-ion accelerator, RAON. The nozzle design was required to produce $C^{12}$ beam satisfying the three conditions; the maximum field size, the dose uniformity and the beam contamination. We employed the GEANT4 toolkit in Monte Carlo simulation to optimize the nozzle design. The beams for biomedical researches were required that the maximum field size should be more than $15{\times}15cm^2$, the dose uniformity was to be less than 3% and the level of beam contamination due to the scattered radiation from collimation systems was less than 5% of total dose. For the field size, we optimized the tilting angle of the circularly rotating beam controlled by a pair of dipole magnets at the most upstream of the user beam line unit and the thickness of the scatter plate located downstream of the dipole magnets. The values of beam scanning angle and the thickness of the scatter plate could be successfully optimized to be $0.5^{\circ}$ and 0.05 cm via this Monte Carlo simulation analysis. For the dose uniformity and the beam contamination, we introduced the new beam configuration technique by the combination of scanning and static beams. With the combination of a central static beam and a circularly rotating beam with the tilting angle of $0.5^{\circ}$ to beam axis, the dose uniformity could be established to be 1.1% in $15{\times}15cm^2$ sized maximum field. For the beam contamination, it was determined by the ratio of the absorbed doses delivered by $C^{12}$ ion and other particles. The level of the beam contamination could be achieved to be less than 2.5% of total dose in the region from 5 cm to 17 cm water equivalent depth in the combined beam configuration. Based on the results, we could establish the optimized nozzle design satisfying the beam conditions which were required for biomedical researches.

Evaluation of Quality Characteristics and Definition of Utilization Category in Korean Potato (Solanum tuberosum L.) Cultivars (국내산 감자(Solanum tuberosum L.)의 품종별 품질특성 평가 및 용도구분)

  • Lee, Yeh-Jin;Jeong, Jin-Cheol;Yoon, Young-Ho;Hong, Su-Young;Kim, Su-Jeong;Jin, Yong-Ik;Nam, Jeong-Hwan;Kwon, Oh-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.57 no.3
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    • pp.271-279
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    • 2012
  • Total twenty cultivars of potato (Solanum tuberosum L.) were grown at Gangneung where is located in low land of Korea. Their tubers were harvested from 100 to 120 days after planting, and over 150 g of tubers were selected for quality evaluation. Dry matter, starch, amylose in starch, ascorbic acid, protein, individual sugars and mineral were analyzed and mealiness of cooked potatoes were also evaluated by panel test. Dry mater content was the highest in 'Haryeong', 'Jayoung' and 'Shepody', and the biggest starch granules were observed in 'Jayoung' and 'Sinnamjak'. In addition, the content of amylose was highest in 'Haryeong', 'Chudong' and 'Goun'. Mineral content showed the slight difference between cultivars, but it's tendency was not clear. Vitamin C content was highest in 'Jayoung' as 62.5 $mg{\cdot}100g^{-1}$ FW, and 'Chugang' exhibited the highest content of protein. Sugar content was lower in cultivars for single one than double cropping. The lowest sugar content was observed in 'Atlantic' and 'Namseo' among cultivars for single cropping, and in 'Goun' for double cropping. As a result of analysis for quality factors, we could select nine cultivars ('Atlantic', 'Gahwang', 'Gawon', 'Goun', 'Hareong', 'Irish Cobbler', 'Jasim', 'Jayoung' and 'Shepody') with high dry matter content and low reducing sugar as a cultivar group for processing. Additionally, seven cultivars ('Chugang', 'Gawon', 'Goun', 'Hareong', 'Irish Cobbler', 'Jasim' and 'Seohong') with high mealiness and amylose content and five cultivars ('Atlantic', 'Chudong', 'Gahwang', 'Jopung' and 'Jowon') with low mealiness and amylose content were classified as groups for boiled or steam cooking and for soup or pot dishes, respectively.