• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.478-490
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• 2021

We aimed to generate basic breeding data for melon (Cucumis melo L.). A total of 219 melon accessions conserved at the National Agrobiodiversity Center (NAC) in Rural Development Administration (RDA) were used in this study, of which 72 (33%) were collected from India. The majority of accessions showed orange (42%) and white (36%) flesh color. In addition to phenotypic evaluations, the accessions were genotyped using a molecular marker for the carotenoid biosynthesis gene CmOr. DNA fragments of the expected size were amplified in 205 out of 219 accessions. Digestion of the PCR products with HinfI restriction endonuclease showed 100% concordance between phenotype and genotype in green-fleshed accessions, but 98%, 97%, and 80% concordance in orange-, white-, and creamy-fleshed accessions, respectively. Sequence analysis revealed single nucleotide changes in the three positions of SNP1, SNP2 and SNP1int in the CmOr gene among accessions. These newly found alleles suggest that there are multiple mechanisms in determining fruit flesh color in melon. Also, the phenotype data of diverse accessions obtained in this study will be a valuable source for melon breeding.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.2
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• pp.73-77
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• 2021

Ga-doped ZnO thin films by RF magnetron sputtering process were synthesized according to the deposition conditions of O2 and Ar atmosphere gases, and rapid heat treatment (RTA) was performed at 600℃ in an N2 atmosphere. The thickness of the deposited ZnO : Ga thin film was measured, the crystal phase was investigated by XRD pattern analysis, and the microstructure of the thin film was observed by FE-SEM and AFM images. The intensity of the (002) plane of the X-ray diffraction pattern showed a significant difference depending on the deposition conditions of the thin films formed by O2 and Ar atmosphere gas types. In the case of a single thin f ilm doped with Ga under O2 conditions, a strong diffraction peak was observed. Under O2 and Ar conditions, in the case of a multilayer thin film with Ga doping, only a peak on the (002) plane with a somewhat weak intensity was shown. In the FE-SEM image, it was observed that the grain size of the surface of the thin film slightly increased as the thickness increased. In the case of a multilayer thin film with Ga doping under O2 and Ar atmosphere conditions, the specific resistance was 6.4 × 10-4 Ω·cm. In the case of a single thin film with Ga doping under O2 atmosphere conditions, the resistance of the thin film decreased. The resistance decreased as the thickness of the Ga-doped ZnO thin film increased to 2 ㎛, showing relatively a low specific resistance of 1.0 × 10-3 Ω·cm.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.25-37
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• 2020

In this study, hybridization of graphene oxide and metal was carried out by the functional groups containing oxygen and thermal treatment for reduction in order to enhance the electrical conductivity and magnetic properties of graphene materials. Graphene-metal hybrid materials were synthesized using the oxygen-containing functional groups (-OH, -COOH and so on) on the surface of graphene oxide by replacing them with metal ions via ion exchange method as well as thermal reduction. The metals used in this study were Fe, Ag, Ni, Zn, and Fe/Ag, and it was confirmed that metal particles of uniform size were well dispersed on the graphene surface through SEM, TEM, and EDS. All of the metal particles on the graphene surface had an oxide-crystalline structure. To check the electrical properties, sheet resistance of the rGO-metal hybrid sample was measured on the PET film made by the dip-coating, and the specific resistance was calculated by measuring the thickness of the specimen through SEM. As a result, the specific resistance was in the range of 2.14×10-5 and 3.5×10-3 ohm/cm.

• Microbiology and Biotechnology Letters
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• v.48 no.4
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• pp.547-555
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• 2020

Microalgae are a promising resource in energy and food production as they are cost-effective for biomass production and accumulate valuable biological resources. In this study, CO2 assimilation, biomass, and lipid production of 4 microalgal species (Chlorella vulgaris, Mychonastes homosphaera, Coelastrella sp., and Coelastrella vacuolata) were characterized at different CO2 concentrations ranging from 1% to 9%. Microscopic observation indicated that C. vulgaris was the smallest, followed by M. homosphaera, C. vacuolata, and Coelastrella sp. in order of size. C. vulgaris grew and consumed CO2 more rapidly than any other species. C. vulgaris exhibited a linear increase in CO2 assimilation (up to 9.62 mmol·day-1·l-1) as initial biomass increased, while the others did not (up to about 3 mmol·day-1·l-1). C. vulgaris, Coelastrella sp., and C. vacuolata showed a linear increase in the specific CO2 assimilation rate with CO2 concentration, whereas M. homosphaera did not. Moreover, C. vulgaris had a greater CO2 assimilation rate compared to those of the other species (14.6 vs. ≤ 11.9 mmol·day-1·l-1). Nile-red lipid analysis showed that lipid production per volume increased linearly with CO2 concentration in all species. However, C. vulgaris increased lipid production to 18 mg·l-1, compared to the 12 mg·l-1 produced by the other species. Thus, C. vulgaris exhibited higher biomass and lipid production rates with greater CO2 assimilation capacity than any other species.

• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.247-257
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• 2021

In this work, Iron Nano-Particles Impregnated BioChar/bead (INPBC/bead) soil amendment was developed to increase biochar's reactivity to As in soil and preventing possible wind loss. Prior to preparation of INPBC/bead, INPBC was produced utilizing lignocellulosic biomass and Fe(III) solution in a hydrothermal method, followed by a calcination process. Then, the bead type amendment, INPBC/bead was produced by cross-linking reaction of alginate with INPBC. FT-IR, XRD, BET, and SEM-EDS analyses were utilized to characterize the as-synthesised materials. The particle size range of INPBC/bead was 1-4 mm, and different oxygen-containing functional groups and Fe3O4 crystalline phase were produced on the surface of INPBC/bead, according to the characterization results. The soil cultivation test was carried out in order to assess the stabilization performance of INPBC/bead utilizing As and Pb-contaminated soil obtained from an abandoned mining location in South Korea. After 4 weeks of culture, TCLP and SPLP extraction tests were performed to assess the stabilization efficacy of the amendment. The TCLP and SPLP findings revealed that raising the application ratio improved stabilizing efficiency. The As stabilization efficiency was determined to be 81.56 % based on SPLP test findings for a 5% in (w/w) INPBC/bead treatment, and the content of Pb in extracts was reduced to the limit of detection. According to the findings of this study, INPBC/bead that can maintain pH of origin soil and minimize wind loss might be a potential amendment for soil polluted with As and heavy metals.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.208-216
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• 2022

Surface morphology and adsorption characteristics of black and white charcoals prepared from Korean traditional kiln were quantitatively analyzed. TGA and elemental analysis of charcoals were different from produced kiln, and thermal degradation temperature and carbon content of white charcoals were apparently higher than those of black charcoals. Surface morphology shows the activation progressed through the longitudinal direction of woods and new micropores were developed to radial direction on the surface of macropores as the furthermore activation resulting in the pore connection. BET adsorption isotherms show that there are low-pressure hysteresis due to the no desorption of adsorbates, which resulted in unique Type of charcoals overlapping Type I and Type IV. Such a low-pressure hysteresis is occurred from expansion of adsorbates, which were embedded in the micropore entrances and did not get out during the desorption run. The characteristics of charcoals such as specific surface area and pore size distribution did not show correct values depending on not only produced company but also sampling sites of one piece of charcoal. Therefore, it is not easy to suggest the quantitative characteristics of charcoals prepared from Korean traditional kiln. On the other hand, preparation the quality standard of charcoal is necessary for their special uses such as adsorbent.

• Animal Bioscience
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• v.35 no.11
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• pp.1808-1816
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• 2022

Objective: The study of Hanwoo (Korean native cattle) has mainly been focused on meat quality and productivity. Recently the field of microbiome research has increased dramatically. However, the information on the microbiome in Hanwoo is still insufficient, especially relationship between vagina and feces. Therefore, the purpose of this study is to examine the microbial community characteristics by analyzing the 16S rRNA sequencing data of Hanwoo vagina and feces, as well as to confirm the difference and correlation between vaginal and fecal microorganisms. As a result, the goal is to investigate if fecal microbiome can be used to predict vaginal microbiome. Methods: A total of 31 clinically healthy Hanwoo that delivered healthy calves more than once in Cheongju, South Korea were enrolled in this study. During the breeding season, we collected vaginal and fecal samples and sequenced the microbial 16S rRNA genes V3-V4 hypervariable regions from microbial DNA of samples. Results: The results revealed that the phylum-level microorganisms with the largest relative distribution were Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria in the vagina, and Firmicutes, Bacteroidetes, and Spirochaetes in the feces, respectively. In the analysis of alpha, beta diversity, and effect size measurements (LefSe), the results showed significant differences between the vaginal and fecal samples. We also identified the function of these differentially abundant microorganisms by functional annotation analyses. But there is no significant correlation between vaginal and fecal microbiome. Conclusion: There is a significant difference between vaginal and fecal microbiome, but no significant correlation. Therefore, it is difficult to interrelate vaginal microbiome as fecal microbiome in Hanwoo. In a further study, it will be necessary to identify the genetic relationship of the entire microorganism between vagina and feces through the whole metagenome sequencing analysis and meta-transcriptome analysis to figure out their relationship.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.2
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• pp.111-118
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• 2023

In this study, the feasibility of laser patterning on the surface of food packaging polymer film was confirmed, and the surface patterning process conditions of femtosecond laser were established. In addition, it was proved that the surface properties of the film can be changed and controlled through the fabrication of various patterned films on the surface of food packaging films such as HDPE, PP, and PET. Various patterned surfaces, including large-scale circular patterns induced by a single femtosecond laser pulse, roughness patterns achieved by overlapping single pulses by 30%, straight line patterns, roughness patterns obtained by overlapping straight line patterns, and grid patterns formed by intersecting straight line patterns were fabricated. The characteristics of the patterned HDPE, PP, and PET films, based on the surface pattern structure and size, were analyzed using SEM, AFM, and contact angle measurements. Compared to the surface of each control film without femtosecond laser patterning, the contact angles of the surfaces of large-area circular patterning HDPE and PP films, large-area roughness patterning HDPE and PP films by overlapping 30% of single pulses, and large-area roughness patterning PET film by overlapping rectilinear patterning were in the range of 27.1-37.5 degree. This indicated that the HDPE, PP, and PET films became more hydrophilic after patterning. On the other hand, the HDPE film patterned with a large-scale grid pattern exhibited a contact angle of 120.4 degree, indicating that the HDPE film became more hydrophobic after patterning. Therefore, films that have been changed to hydrophilic surfaces through patterning can be used in anti-fouling applications where proteins, cells, viruses, and other food materials do not adhere or are easily detached. In addition, if a superhydrophobic surface of 150 degrees or more is fabricated through more precise lattice patterning in the future, it will be possible to use it for superhydrophobic surface applications such as self-cleaning.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.571-582
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• 2022

In this study, the raw material and tempers of bricks used in three brick tombs built in Gongju, during the Ungjin period of Baekje were investigated. The royal tomb of King Muryeong, the 6th tomb in the royal tombs, and Kyochonri brick tomb remained in Gongju and the bricks of each site had different shape and physical properties despite their similarity in raw materials. As the results of the mineralogical and microstructural analysis, the bricks of the royal tombs were made of refined raw materials, and were infrequently added crushed bricks(grogs) as a tempering material. On the other hand, thick and elongated pores of bricks from the Kyochonri brick tomb were frequently found, and the remains of plant carbonization are observed in their microstructures. Since the pores are mainly distributed in a thickness of 0.3 to 1 mm, it is estimated that bricks were produced by adding a certain size of the plant to refined soil, and grogs also were added as a tempering material. In particular, it was found that adding plants and grogs in raw materials of bricks caused thick pores or cracks in the internal structure. Since the bricks of the Kyochonri brick tomb have internal cracks and low firing temperature, the ultrasonic velocity of the bricks was lower than that of the royal tomb bricks. It means that the mechanical strength of these bricks were relatively low. Accordingly, it is estimated that the tempering materials, firing temperature, and internal structures of bricks can affect durability of the brick, and it can be thought as a difference in the manufacturing technology of brick making.

• Analytical Science and Technology
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• v.21 no.1
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• pp.58-63
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• 2008

Nano-sized ZnO crystals were successfully incorporated using ion exchange method in TMA-A zeolite synthesized by the hydrothermal method. The optimal composition for the synthesis of TMA-A zeolite was resulted in a solution of $Al(i-pro)_3$ : 2.2 TEOS : 2.4 TMAOH : 0.3 NaOH : 200 $H_2O$. 0.3 g of TMA-A zeolite and 5 mol of $ZnCl_2$ solution were employed for the preparation of ZnO incorporated TMA-A zeolite. The crystallization process of ZnO incorporated TMA-A zeolite was analyzed by X-ray diffraction (XRD). The incorporated nano-sized ZnO crystals and the crystallinity of TMA-A zeolite were evaluated by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). The size of the incorporated nano-sized ZnO crystals was 3~5 nm, while the TMA-A zeolite was 60~100 nm. The bonding structure and absorption of the ZnO incorporated TMA-A zeolite were compared with the ZnO and TMA-A zeolite by the FT-IR analysis. Subsequentlly, the ZnO incorporated TMA-A zeolite showed the photoluminescent characteristics on the wavelengths of 330~260 nm and 260~230 nm by measurement of UV spectrophotometer.