자외선차단 화장품은 기능성 화장품 중의 하나로서, 유·무기 자외선차단물질이 함유되어 있다. 무기계 자외선차단제는 주로 산화아연, 이산화티탄 등이 있다. 무기계 자외선차단제는 입자의 지름이 60 ~ 100 nm로 자외선 A, B의 차단능이 좋은 것으로 알려져 있다. 또한 자외선을 포함한 태양광선에 대해 비활성이 크고 안전성이 우수하다. 그리고 유기계 자외선차단제처럼 피부에 흡수 또는 축적되지 않으므로 피부 자극이나 알레르기를 유발하지 않는다. 본 연구에서는 판상 무기안료인 마이카, 자외선차단 효과를 갖는 이산화티탄 나노입자, 소수성 실리카를 각각 계면활성제로 표면처리 하였고, 각 물질의 전하 차이에 따른 비화학적인 상호 인력 작용에 의해 마이카에 이산화티탄 나노입자, 실리카를 물리적으로 흡착시켰다. 이후, 소수성 표면처리제인 실란을 표면처리 하여 소수성을 갖는 자외선 차단 판상 마이카 복합체를 제조하였다. 자외선 차단 판상 마이카 복합체는 일반적인 나노입자 이산화티탄의 응집성을 개선하고 균일한 분산에 따른 자외선차단 효과가 증대되었으며, 소수성으로 표면처리를 하여 화장품 제형에서의 분산안정성을 크게 개선할 수 있었다. 안료의 표면전하는 제타전위로 평가하였으며, 제조된 자외선차단 마이카 복합체의 특성 평가는 FE-SEM, XRD, FT-IR, UV-VIS 등으로 확인하였다.

In this paper, the relationship between the frequency split and the mode-coupling in the disc doublet mode, which is expressed according to the pattern of the surface of the disc, is utilized by using of 3 types(Chaos, Vent-hole, Normal). As the frequency split between the doublet mode disc that is expressed in the model through the interpretation is larger, and analogy through interpretation mode-coupling instability also lower. Vent-hole, which has a relatively large frequency split of disc doublet mode in 3 types(Chaos, Vent-hole, Normal) model, showed a large value of critical coefficient of friction in which mode-coupling instability is expressed. In addition, it was confirmed by analysis that the Vent-hole had a relatively large frequency split than the other models by analyzing the change in contact stiffness. It can be concluded that the larger the frequency split of the disc doublet mode, the lower the instability due to the mode-coupling.

The brake systems are composed of brake disc, brake pad and caliper and, these three parts play an important role for braking. In this study, heat fluid analysis is conducted for five different ventilated disc models, and two piece brake disc model separated in rotor and housing is used. In this case, each model has a different number of holes and vent shape. The basic heat flux and braking power equations are applied for the heat fluid analysis. The cooling performance with/without the braking operation is also analyzed for given five models where the material properties and boundary conditions are set to be identical. From our analysis results, it is found that the number of disc holes and ventilated pins strongly influences on the cooling performance.

The objective of this study was to investigate design factors of the electrolysis reactor through the CFD(computational fluid dynamics) simulation technique. Analyses of velocity vector, streamline, chloride ion concentration distribution showed differences in flow characteristics between the plate type electrode and the porous plate type electrode. In case of the porous plate type electrode, chlorine gas bubbles generated from the anode made upward density flow with relatively constant velocity vectors. Electrolysis effect was more expected with the porous plate type electrode from the distribution of chloride ion concentration. The upper part of the electrolysis reactor with the porous plate type electrode had comparatively low chloride concentration because chloride was converted to the chlorine gas formation. Decreasing the size and increasing total area of rectifying holes in the upper part of cathodes, and widening the area of the rectifying holes in the lower part of cathodes could improve the circulation flow and the efficiency of electrolysis reactor.

The dewatering characteristics of the sewage sludge was investigated through the experimental observations and model simulations. The activated sludge and the anaerobically digested sludge were examined for the dewaterability evaluation within the pressure range of $0{\sim}10^6N/m^2$. Modified Buchner funnel test and compression test by the consolidometer were conducted to evaluate average specific resistance, porosity, and moisture percentage of filter cake. Shirato's technique of compression-permeability test was followed for the pressure range lower than about $10^2N/m^2$. The flocculation effects on sludge dewatering was also examined for ferric chloride and polymeric flocculant. The application of hydrated lime which can be used for flue-gas desulfurization showed improved moisture percentage, and was thought to have positive feasibility in combined system of sludge dewatering and incineration. Determined characteristic constants were applied to Tiller's cake filtration model to simulate liquid pressure distribution and porosity distribution in cake. Model simulations showed a sharp drop of the porosity close to the cake-medium interface for the highly compressible material such as the activated sludge and the anaerobically digested sludge.

Background : Jujube (Zizyphus jujuba. Mill) is a broad-leaved shrub belonging to the family Seagull. Its origin is India and its height is about 5 m. The flowers are gathered in two to three in May-June, with five petals and yellowish green. Leaves are alternate, egg-shaped or long egg-shaped, with clearly visible three veins. The fruit, called jujube, is an elliptical nucleus with the seed wrapped in a solid nucleus. It is 2.5 - 3.5 ㎝ in length, green at first, ripened in brown or reddish brown in September-October. Jujube uses the bud mutation to breed and spreads through grafting. Therefore, there is little difference in phenotype between cultivars. However, because of the lack of research on jujube molecular biology, there is no standard to distinguish the variety at the DNA level. In order to overcome such difficulties and to create a research foundation of jujube, we have developed molecular markers from jujube. Methods and Results : We collected 12 jujube varieties include Bogjo and extracted DNA using CTAB method. The DNA was diluted to 10 ng/㎕ and kept at -20℃. We designed the primer sets using CLC Main Workbench based on DNA InDel regions between the varieties. PCR and electrophoresis were performed to confirm the polymorphism. We designed 26 primer sets from 23 InDel regions. Eighteen of 26 primer sets amplified the amplicon from the primer screening. Eight primer sets were selected for polymorphism assays. All primer sets showed polymorphism. The domesticated cultivars were divided into two groups and the Japanese and Chinese varieties were separated. Conclusion : The InDel markers developed in this study could be good tools to differentiate the jujube cultivars cultivated in Korea.

Background : Angelica species are representative medicinal plants and it has been used in traditional medicinal methods, especially, in the traditional Asian medicine. The Angelica species used in conventional medicine varies by country according to specific regulations, i.e. A. gigas Nakai in Korea, A. sinensis Diels in China, and A. acutiloba Kitagawa in Japan. Because of the similarity between the names among Angelica, they can be confused in the market. Methods and Results : In this study, twenty-four chloroplast insertion or deletion (cpInDel) markers were developed from chloroplast DNA of A. gigas Nakai and tested for the classification of Angelica species. Primer sets were designed from flanking sequences of the discovered InDel loci from chloroplast DNA of A. gigas Nakai using CLC Main Workbench with the following parameters : primer length = 18 - 26 bp (Opt. 23 bp); GC% = 50 - 70% (Opt. 60%); Ta = 55 - 62℃ (Opt. 58℃); product size range = 120 - 300 bp. Polymorphism and genotype analysis of 13 Angelica species were performed using the developed cpInDel markers. Conclusion : The 24 cpInDel markers developed in this study could be used for genetic diversity analysis and classification of Angelica species.

Background : The Codonopsis genus belongs to the Campanulaceae, and it is recorded that there are four species of Codonopsis genus in Korea, such as Codonopsis lanceolata, Codonopsis pilosula, Codonopsis minima, and Codonopsis ussuriensis. C. lanceolata has been proved to be safety and efficacy, and has been widely used for medicinal and edible purposes for a long time in East Asian countries including Korea, China and Japan. However, little genetic research has been done. Methods and Results : Ten species of Codonopsis plants were collected and DNA was extracted using CTAB (cetyl trimethylammonium bromide) method. The extracted DNA was diluted to 5 ng/㎕ for the PCR (polymerase chain reaction) process. C. lanceolata genome was used to develop molecular markers by searching insertion and deletion regions (InDel) in the chloroplast sequence. The developed markers were applied to 4 individuals per Codonopsis species. PCR amplification was carried out using a denaturation at 94℃ for 30 sec, annealing at 58℃ for 30 sec and extension at 72℃ for 30 sec, repeated for 35 total cycles. The PCR products were separated in a 4% agarose gell at 100 V for 40 min. Conclusion : Using the molecular markers developed in this study, genetic diversity of Codonopsis genus was tested, and at the same time, a specific molecular marker was developed to differentiate C. lanceolata from the Codonopsis plants.

Background : Codonopsis lanceolata is a perennial plant of Campanulaceae and mainly distributed in East Asia such as Korea, China, and Japan. C. lanceolata has a unique taste and aroma, and it is rich in minerals such as phosphorus and calcium, and vitamin B1 and B2, so our ancestors used the plant as medicinal herb and edible vegetable. However, systematic cultivation and development of varieties have not been achieved compared to demand or high added value. The genetic diversity and relationship analysis of the plants help to increase the efficiency of breeding through genetic variation. Methods and Results : Ten species of Codonopsis plants were used as materials and DNA was extracted from each 4 individuals per species and quantified at a concentration of 10 ng /㎕. The extracted DNA was pooled by species and PCR was performed using the EST-SSR marker developed based on C. lanceolata in the previous study. PCR amplification was carried out using a denaturation at 94℃ for 30 sec, annealing at 58℃ for 30 sec and extension at 72℃ for 30 sec, repeated for 35 total cycles. The PCR products were separated in a 4% agarose gell at 100 V for 40 min. Conclusion : In this study, C. lanceolata collections was determined among several Codonopsis species using these molecular marker. It is expected that the data of this study can be used as reference for genetic polymorphism analysis and related gene studies of Codonopsis species.

Background : Codonopsis lanceolata is a perennial plant of Campanulaceae with characteristic flavor and aroma and this plant has saponin, flavonoid, and inulin, which are reported to have physiological activity and antioxidant activity. In contrast, breeding or study of C. lanceolata varieties had not been done for a long time. Genetic polymorphism and phylogenetic relationship analysis of the plants by region of the crops can help the collection of genetic backgroud data for variety development. Methods and Results : In this study, we collected 26 C. lanceolata lines (95 individual plants) from 26 regions in Korea. We genotyped the collected lines using SSR markers developed in the previous study and analyzed the population structure based on the results. Population structures were analyzed using model-based STRUCTURE software (version 2.3.4) using the following parameters: Number of clusters (K) set = 1 to 12; Number of Iterations = 5; Length of Burning Period = 100,000; Number of MCMC (Markov Chain Monte Carlo) Reps after Burnin = 100,000. As a result, Of the 26 collections, were genetically grouped into 6 or 7 groups. Conclusion : The 26 C. lanceolata collections (95 individual plants) were genetically grouped but not grouped by collected regions. These results suggest that C. lanceolata has diverse genetic backgrounds and this data could be used as a basis for genetic polymorphism analysis of Codonopsis species.