• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.43 no.1
• /
• pp.61-68
• /
• 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.

• Korean Chemical Engineering Research
• /
• v.52 no.3
• /
• pp.321-327
• /
• 2014

Polymer dispersed liquid crystal lenses of the cell gap of $11{\mu}m$ and $30{\mu}m$ were made from a uniformly dispersed mixture of 40 wt% NOA65 prepolymer - 60 wt% E7 liquid crystal with the variations of the additional photoinitiator. The photoinitiator, benzophenone of 5.0 wt% was originally in the commercial prepolymer NOA65. In this works, the influence of the benzophenone amount intentionally added in the commercial NOA65 on the electrical properties of polymer dispersed liquid crystal lens for smart electronic glasses. The additional quantities of the photoinitiator were 1, 2, 4, 8 and 16 wt% of the weight of NOA65 - E7 mixture. All the electro-optical properties of the sample with added benzophenone such as the driving voltage, the slope of the linear region, the response time and contrast ratio were more improved than that of commercial NOA65 only. These improvements were due to the increase of the average size of E7 liquid crystal droplets in the samples with the increase of the added benzophenon amount. The liquid crystal droplet size was increased from $5.3{\mu}m$ to $12.2{\mu}m$ when the photoinitiator was added from 0 wt% to 8 wt%. At the same concentration range of the photoinitiator, the driving voltage was ranged from 11.1 V to 17.3 V. The slopes of the linear region were in the range of 10.35~13.96 %T/V, which were more enhanced than that of NOA65 without the additional benzophenone. In particular, though the deteriorations by cell gap of $11{\mu}m$ were so effective to offset the influence of the added benzophenone for both rising and falling response time, it is confirmed that there were still somewhat improvement by the additional benzophenone. Response time and contrast ratios of all the samples with excess benzophenone were slightly enhanced.

• Journal of Biomedical Engineering Research
• /
• v.23 no.2
• /
• pp.147-153
• /
• 2002

The purpose of this study was to evacuate the effect of different types of Poly(lactic-co-glycolic acid) (PLGA) scaffolds on the formation of human auricular and septal cartilages. All of the scaffolds were formed in a tubular shape for potential application for artificial trachea or esophagus with either 110,000 g/mol PLGA. 220,000 g/mol PLGA. or a combination of both. In order to maintain the tubular shape in vivo, two methods were used. One method was inserting polyethylene tube at the center of scaffolds made of 110,000 g/mol PLGA. The other method involved combination of the two different molecular weight PLGA's. The inner surface of tubular shaped scaffold made with 110,000 g/mol PLGA was coated with 220,000 9/mol PLGA to give more mechanical rigidity. Elastic cartilage was taken from the ear of a patient aged under 20 nears old and hyaline cartilage was taken from the nasal septum. The chondrocytes were then isolated. After second passage, the chondrocytes were seeded on the PLGA scaffolds followed by in vitro culture for one week. The cells-PLGA scaffold complex were implanted subcutaneously on the back of nude mice for 8 weeks. The tissue engineered cartilages were separated from nude mice and examined histologically after staining with the Hematoxylin Eosin. The morphology of the scaffolds were examined by scanning electron microscopy. The pores were well formed and uniformly distributed in the various PLGA scaffolds. After 8 weeks in vivo culture, cartilage was well formed with 110,000 g/mol PLGA. however lumen had collapsed. In contrast. a minimal amount of neocartilage was formed with 220,000 g/mol PLGA, while the architecture of scaffold and lumen were well preserved. Elastic cartilage formed more neocartilage than hyaline. Hyaline and elastic neocartilage were well formed on 110,000 g/mol PLGA with the polyethylene tube, exhibiting mature chondrocytes and preservation of the tubular shape. It was found that 110,000 g/mol PLGA was more appropriate for cartilage formation but higher molecular weight polymer was necessary to maintain the three dimensional shape of the scaffold.

• Journal of the Korean Vacuum Society
• /
• v.17 no.6
• /
• pp.538-543
• /
• 2008

Recently a nano-scale diamond is possible to manufacture forms of powder(below 100 nm) by new processing of explosion or deposition method. Using a sintering of nano-scale diamond is possible to manufacture of grinding tools. We have need of a processing development of coated uniformly inorganic to prevent an abnormal grain growth of nano-crystal and bonding obstacle caused by sintering process. This paper, in order to improve the sintering property of nano-scale diamond, we coated ZnO thin films(thickness: $20{\sim}30\;nm$) in a vacuum by ALD(atomic layer deposition) Economically, in order to deposit ZnO all over the surface of nano-scale diamond powder, we used a new modified fluidized bed processing replaced mechanical vibration effect or fluidized bed reactor which utilized diamond floating owing to pressure of pulse(or purge) processing after inserted diamond powders in quartz tube(L: 20 mm) then closed quartz tube by porosity glass filter. We deposited ZnO thin films by ALD in closed both sides of quartz tube by porosity glass filter by ALD(precursor: DEZn($C_4H_{10}Zn$), reaction gas: $H_2O$) at $10^{\circ}C$(in canister). Processing procedure and injection time of reaction materials set up DEZn pulse-0.1 sec, DEZn purge-20 sec, $H_2O$ pulse-0.1 sec, $H_2O$ purge-40 sec and we put in operation repetitive 100 cycles(1 cycle is 4 steps) We confirmed microstructure of diamond powder and diamond powder doped ZnO thin film by TEM(transmission electron microscope) Through TEM analysis, we confirmed that diamond powder diameter was some $70{\sim}120\;nm$ and shape was tetragonal, hexagonal, etc before ALD. We confirmed that diameter of diamond powders doped ZnO thin film was some $70{\sim}120\;nm$ and uniform ZnO(thickness: $20{\sim}30\;nm$) thin film was successfully deposited on diamond powder surface according to brightness difference between diamond powder and ZnO.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.1
• /
• pp.35-39
• /
• 2009

Purpose: Diagnostic and functional imaging softwares in Nuclear Medicine have been developed significantly. But, there are some limitations which like take a lot of time. In this article, we introduced that the basic concept of macro to help understanding macro and its application to Brain SPECT processing. We adopted macro software to SPM processing and PACS verify processing of Brain SPECT processing. Materials and Methods: In Brain SPECT, we choose SPM processing and two PACS works which have large portion of a work. SPM is the software package to analyze neuroimaging data. And purpose of SPM is quantitative analysis between groups. Results are made by complicated process such as realignment, normalization, smoothing and mapping. We made this process to be more simple by using macro program. After sending image to PACS, we directly input coordinates of mouse using simple macro program for processes of color mapping, adjustment of gray scale, copy, cut and match. So we compared time for making result by hand with making result by macro program. Finally, we got results by applying times to number of studies in 2007. Results: In 2007, the number of SPM studies were 115 and the number of PACS studies were 834 according to Diamox study. It was taken 10 to 15 minutes for SPM work by hand according to expertness and 5 minutes and a half was uniformly needed using Macro. After applying needed time to the number of studies, we calculated an average time per a year. When using SPM work by hand according to expertness, 1150 to 1725 minutes (19 to 29 hours) were needed and 632 seconds (11 hours) were needed for using Macro. When using PACS work by hand, 2 to 3 minutes were needed and for using Macro, 45 seconds were needed. After applying theses time to the number of studies, when working by hand, 1668 to 2502 minutes (28 to 42 hours) were needed and for using Macro, 625 minutes (10 hours) were needed. Following by these results, it was shown that 1043 to 1877 (17 to 31 hours were saved. Therefore, we could save 45 to 63% for SPM, 62 to 75% for PACS work and 55 to 70% for total brain SPECT processing in 2007. Conclusions: On the basis of the number of studies, there was significant time saved when we applied Macro to brain SPECT processing and also it was shown that even though work is taken a little time, there is a possibility to save lots of time according to the number of studies. It gives time on technologist's side which makes radiological technologist more concentrate for patients and reduce probability of mistake. Appling Macro to brain SPECT processing helps for both of radiological technologists and patients and contribute to improve quality of hospital service.

• Korean Journal of Weed Science
• /
• v.16 no.1
• /
• pp.21-27
• /
• 1996

This experiment was conducted to find out an effective propagation method for reed(Phragmites communis Trin.), ensuring a continuous herbicide screening for reed control. Reed propagation methods were compared under a greenhouse condition using tour different materials; seeds, rhizomes, depressed stolons of P. japonica Steud., and stem cuttings. Although reed seeds were easy to harvest and store, their germination rate(${\leq}$5%) was very low and seedling growth from the seeds was slow. Rhizomes were difficult to harvest and their harvest time was limited from November to March. Furthermore, reed propagation using rhizomes had problems of a relatively low germination rate(46%), no uniformity in size and shape, individual differences at the early stage of growth, and difficulties in material storage. Rate of reed growth from rhizomes was higher in commercial soil mix(Boo Nong soil) than in sand or in sand+upland soil(1:1). Depressed stolons of P. japonica had a moderate germination rate(65%) and were relatively easy to harvest. However, their harvest time was limited only from August to September. Propagation method using stem cuttings had several advantages over the above methods using other materials. Reed plants could uniformly be propagated from the stem cuttings with a relatively high germination rate(75%). Stem cuttings of central nodes showed a higher germination rate compared to those of upper or lower nodes. Stem cuttings from the field should be used immediately after harvest, since their germination rate decreased rapidly when they were stored under a wet- or a dry-refrigerated condition. Furthermore, the germination of stem cuttings tended to decrease when they were collected from the field after August. This indicates that there is a limitation of harvest time for stem cuttings. However, a year-round propagation of reed using stem cuttings is possible if parent plants are grown in a greenhouse, and thus herbicide screening for reed control could continuously be performed.

• 한국해양학회지
• /
• v.27 no.3
• /
• pp.210-227
• /
• 1992

KODOS-89 area, the northwestern part of Clarion-Clarion-Clipperton fracture zones in the Northeast Pacific, was surveyed in order to study the occurrence and distribution of manganese nodules. Variations in the nodule characteristics are related mainly to seafloor topography. Nodules from abyssal plain have high Mn/Fe ratio and high Mn, Cu, Ni and Zn concentrations, whereas those from seamount are characterized by low Mn/Fe ratio and high Fe and Co concentrations. These compositional characteristics are attributed to toxic diagnosis and hydrogenesis, respectively. Nodules of the early diegenetic origin tend to accurate crystalline Mn-oxides uniformly within the topmost sediment layers and maintain a regular spheroidal, ellipsoidal to discoidal shape with rough surface textures. On the other hand, those of hydrogenetic origin are characterized by polynucleation, irregualr shape, and smooth surface textures. Nodule abundance is high (avg. 13.4 kg/m$^2$) in seamount area, resulting from ample supply of nucleating materials by auto-fragmentation of older nodules. Nodule abundance in abyssal plain is relatively low (avg. 3.9 kg/m$^2$) and tends to increase southward. This phenomenon results from facilitation of taking seed materials from adjacent seamount and enhancement of the early diagenesis by sufficient supply of organic materials. Nodule abundance is considered to be controlled primarily by seeding effects and secondly by supplies of organic materials.

• Korean Journal of Heritage: History & Science
• /
• v.38
• /
• pp.329-358
• /
• 2005

The Three storied Stone pagoda in Gameunsa Temple site, one of the early staged stone pagodas, has been known as a standard for Silla stone pagodas. A stone pagoda is not only a stone art work and but also a stone structure. Most studies and investigation of the stone pagoda has done mainly based on style and chronological research according to an art historical view. However, there is not an attempt to research the stone pagoda as a stone architecture. Most Korean experts at the stone pagoda has art history in their background. Engineers who can understand the structure of the stone pagoda are very limited. More architectural and engineering approach is need to research not only art historial understanding but also safety as a structure. We can find many technical know-how from our ancestors who made stone pagodas. 1. To reduce any deformation such as relaxation and sinking of BuJae which is caused by a heavy load, the BuJae (consist of a foundation stone and lower stereobates) should be enlarged. 2. A special construction method for connection between Myonsuk and Tangjoo was invented. This unique method is not used any longer after the Three storied Stone pagoda in Gameunsa Temple site. 3. The upper BuJae and the lower BuJae are missed each other by making a difference of Okgaesuk and Okgaebatchim in size. It is done for a distribution of perpendicular load and a prevention for relaxation of BuJae. 4. The center of gravity in the BuJae is located to the center of the stone pagoda by trimming the upper surface of the Okgaebatchim into a convex shape. The man who made stone pagodas had excellent knowledge on the engineering and techniques to understand the structure of the stone pagodas. We can confirm it as follows: the enlarged BuJae, dislocated connection between upper Bujae and lower BuJae, and moving the center of gravity close to the center of the stone pagoda.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.6
• /
• pp.454-459
• /
• 2009

In order to identify the effect of soil salinity on saturated hydraulic conductivity in reclaimed paddy soils, we established the soil columns uniformly packed with soils collected at every 20 cm up to 60 cm from the reclaimed paddy area with high and low salinity which has been cultivated rice plants for the last 30 years. The soil textures were sandy loam and loamy sand for high-salinity and low-salinity topsoils, respectively. For high-salinity and low-salinity soils the ECes were ranged from 25.2 to $37.8dS\;m^{-1}$ and 3.0 to $3.4dS\;m^{-1}$ while the ESPs were ranged from 7.70 to 20.84 % and from 5.12 to 11.33 %, respectively. The bulk densities of the soil columns were adjusted to $1.15{\pm}0.03g\;cm^{-3}$. The results of the soil column experiments shows that the stabilized saturated hydraulic conductivity of low-salinity soil was $0.62cm\;hr^{-1}$ at the topsoil while there were little water flow at the bottom of the soil columns packed with high-salinity soils. After removal of $Na^+$ ions with $1N\;NH_4OAc$ from the high-salinity soil, Ksat of the saline soil was drastically increased to $0.23cm\;hr^{-1}$. Soil columns of high-salinity topsoil treated with four different concentration of NaCl influent after removal of soluble and exchangeable cations with $1N\;NH_4OAc$ show Ksat in the range of $0.1{\sim}0.15cm\;hr^{-1}$ and the Ksat slightly decreased as the concentration of NaCl influent was increasing. Conclusively, we could assume that $Na^+$ can be significantly contributed to the saturated hydraulic conductivity in newly reclaimed sandy soil.

• The Korean Journal of Nuclear Medicine
• /
• v.34 no.1
• /
• pp.62-73
• /
• 2000

Purpose: Esophageal cancer patients have a difficulty in the intake of meals through the blocked esophageal lumen, which is caused by an ingrowth of cancer cells and largely influences on the prognosis. It is reported that esophageal cancer has a very low survival rate due to the lack of nourishment and immunity as the result of this. In this study a new radioactive stent, which prevents tumor ingrowth and restenosis by additional radiation treatment, has been developed. Materials and Methods: Using ${\ulcorner}HANARO{\lrcorner}$ research reactor, the radioactive stent assembly ($^{166}Ho$-SA) was prepared by covering the metallic stent with a radioactive sleeve by means of a post-irradiation and pre-irradiation methods. Results: Scanning electron microscopy and autoradiography exhibited that the distribution of $^{165/166}Ho\;(NO_3)$ compounds in polyurethane matrix was homogeneous. A geometrical model of the esophagus considering its structural properties, was developed for the computer simulation of energy deposition to the esophageal wall. The dose distributions of $^{166}Ho$-stent were calculated by means of the EGS4 code system. The sources are considered to be distributed uniformly on the surface in the form of a cylinder with a diameter of 20 mm and length of 40 mm. As an animal experiment, when radioactive stent developed in this study was inserted into the esophagus of a Mongrel dog, tissue destruction and widening of the esophageal lumen were observed. Conclusion: We have developed a new radioactive stent comprising of a radioactive tubular sleeve covering the metallic stent, which emits homogeneous radiation. If it is inserted into the blocked or narrowed lumen, it can lead to local destruction of the tumor due to irradiation effect with dilatation resulting from self-expansion of the metallic property. Accordingly, it is expected that restenosis esophageal lumen by the continuous ingrowth and infiltration of cancer after insertion of our radioactive stent will be decreased remarkably.