• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.308-316
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• 2019

Electron beam physical vapor deposition (EBPVD) is a conventional method to fabricate thermal barrier coating (TBC) of high temperature airfoil engine parts, such as blade etc. for its high temperature structural stability from the nature of columnar growth behavior. For the high quality of TBC by EBPVD, the structural factors, such as growth behavior, thickness uniformity and so on, should be managed to obtain the coating which satisfied the required specifications of usable level of mechanical and thermal properties. In this study, the growth behavior and structure variations of 7YSZ (7 wt% yttria stabilized zirconia) coatings with different configurational deposition parameters for the specimens which have turbine blade shape mock-up were investigated. Growth behavior of coatings were studied by comparing computational modeling of evaporation behavior with actual deposition process using e-beam source.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.799-802
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• 2012

Background: Human papillomavirus (HPV) is a very common sexually transmitted disease affecting both men and women and is responsible for different ano-genital cancers in either sex. Co-existing sexually transmitted infections (STI) including HIV have been considered as important co-factors for carcinogenesis induced by HPV. The purpose of this study was to determine the prevalence of any HPV, HPV 16 and HPV 18 and also concomitant STIs among female sex workers (FSW), men having sex with men (MSM) and injectable drug users (IDU). Material and Method: This cross-sectional study was conducted among 45 FSWs, 26 MSMs and 58 IDUs who attended the STI or de-addiction clinics. Genital scrape samples collected from glans penis and coronal sulcus in males and cervical squamo-columnar junction in females were tested for HPV DNA by PCR using HPV L1 consensus primer. Type specific PCR to detect HPV 16 and 18 was done on the samples positive on consensus PCR. All participants were tested for associated STIs including HIV and hepatitis B and cervical cytology was done on all females. Results: Among the FSWs, HPV was detected in 73.3% and HPV 16 and 18 was detected in 25.7%. Though the HPV prevalence was similarly high among MSMs (69.2%) and IDUs (72.4%), the prevalence of HPV 16 and 18 was much lower in these groups compared to the FSWs. Prevalence of cervico-vaginal infection with Trichomonas vaginalis and syphilis was significantly higher in the HPV positive women compared to the HPV negative women. There was no statistically significant difference in the prevalence of other STIs among HPV positive and negative women and men. Conclusion: HPV infection is highly prevalent among FSW, MSM and IDUs. Trichomonas vaginalis infection is more frequent in HPV positive women.

• Korean Journal of Materials Research
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• v.20 no.12
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• pp.661-668
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• 2010

Cu(In,Ga)$Se_2$(CIGS) photovoltaic thin films were electrodeposited on Mo/glass substrates with an aqueous solution containing 2 mM $CuCl_2$, 8 mM $InCl_3$, 20 mM $GaCl_3$ and 8mM $H_2SeO_3$ at the electrodeposition potential of -0.6 to -1.0 V(SCE) and pH of 1.8. The best chemical composition of $Cu_{1.05}In_{0.8}Ga_{0.13}Se_2$ was found to be achieved at -0.7 V(SCE). The precursor Cu-In-Ga-Se films were annealed for crystallization to chalcopyrite structure at temperatures of 100-$500^{\circ}C$ under Ar gas atmosphere. The chemical compositions, microstructures, surface morphologies, and crystallographic structures of the annealed films were analyzed by EPMA, FE-SEM, AFM, and XRD, respectively. The precursor Cu-In-Ga-Se grains were grown sparsely on the Mo-back contact and also had very rough surfaces. However, after annealing treatment beginning at $200^{\circ}C$, the empty spaces between grains were removed and the grains showed well developed columnar shapes with smooth surfaces. The precursor Cu-In-Ga-Se films were also annealed at the temperature of $500^{\circ}C$ for 60 min under Se gas atmosphere to suppress the Se volatilization. The Se amount on the CIGS film after selenization annealing increased above the Se amount of the electrodeposited state and the $MoSe_2$ phase occurred, resulting from the diffusion of Se through the CIGS film and interaction with Mo back electrode. However, the selenization-annealed films showed higher crystallinity values than did the films annealed under Ar atmosphere with a chemical composition closer to that of the electrodeposited state.

• Journal of Korean Society of Forest Science
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• v.4 no.1
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• pp.9-13
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• 1965

Powdery mildew of Ailanthus altissima Sw. was first reported by J.S. Park in Korea, 1961. According to his report, this disease was found on the leaves of this tree species collected in Jeongup, 1957, and in Taejon, 1958. He described morphological characters of this pathogen and described also that the causal fungus may be closely related with Phyllactinia corylea. This disease which appears dusty grayish yellow molds under surface of leaves was collected again by the author in Kwangju, 1962. The present works were undertaken to make clear the species of causal fungus by means of the morphology and pathogenecity. According to the following results, the pathogen was identified as Phyllactinia corylea (Pers.) Karst. Morphological characters of the fungus Mycelia persistent or more or less evanescent; matured conidia solitary, aseptate, short-clavate to clavate to clavate, hyaline or yellowish, granulate, $44.6-89.2{\times}9.3-24.2{\mu}$, average $64.8-17.8{\mu}$ in size; conidiophores elongate clavate or columnar, hyaline, 2-3 septate, $122.8-346.0{\times}3.7-7.4{\mu}$, average $208.8{\times}6.3{\mu}$; per-thecia usually scattered, rarely gregarious, dark brown to black, depressed globose to globose, $223.2-297.6{\mu}$, average $267.8{\mu}$ in diameter; appendages 12-19, usually 15 in number, hyaline, straight, needle-shaped, sharply pointed at the apex and bulbous at the base, aseptate, $93.0-310.0{\times}5.0-8.0{\mu}$, average $173.3{\times}6.4{\mu}$ in size; asci elongate ellipsoidal to broadly clavate, hyaline, more or less stalked, 8-13 in number, $68.5-76.6{\times}26.1-34.2{\mu}$, average $71.4{\times}29.0{\mu}$ in size; ascospores 2-4, usually 2 in number, hyaline or yellowish, aseptate, ellipsoidal or ovate, $27.7-34.2{\times}14.7-17.9{\mu}$, average $25.5{\times}13.9{\mu}$ in size. Pathogenicity of the fungi In order to make clear the species of the fungus and the pathogenic differences of Phyllactinia fungi which are collected around the contaminated area and seemed to be related to Ailanthus powdery mildew, some inoculation experiments were performed. 1. Cross inoculation to several tree species with their pathogen: Tested materials; Phyllactinia in question on Ailanthus altissima Sw. Ph. fraxini (DC.) Homma. On Alnus firma S. et Z. Ph. moricola (P. Henn.) Homma on morus alba L. According to the results of the experiments, the reactions were all negative with the exception of the original hosts of tested fungi. 2. Inoculation to Picrasma ailanthoides Planch. : The appearance of symptom on the leaves of P. ailanthoides is not distinct, but more or less mycelial growth. Therefore, under the optimal condition in glass chamber, it may be possible to success artificially.

• Economic and Environmental Geology
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• v.33 no.5
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• pp.391-404
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• 2000

This study investigated the geochemical characteristics of mine drainage discharged from an abandoned coal mine in the Hwasoon area. Surface water samples were collected from 23 locations along the Hancheon creek. The concentration of Zn and Cu in stream waters was highest at low pH (3.53), whereas the content of TDS and TDI was highest at high pH (7.78) due to the concentration of Ca, $HCO_3$ and $SO_4$. At the upstream site, the Ba, Fe, Mn, Zn, and $SO_4$ contents were relatively high but decreased significantly with the distance from the coal mine. On the contrary, the Na and $NO_3$ contents were low at the upstream site but increased downstream. Yellow precipitate material collected in the Hancheon consisted mainly of iron and LOI. This yellow precipitate was heated from 100 to $900^{\circ}C$ for 1 hour. With increasing temperature, the intensity of hematite peaks were sharply produced in X-ray pattern and the absorption band Fe-O of hematite increased in IR due to dehydration and melting. The yellow to brown precipitate and evaporite materials were collected by a air-dry from the acid mine water at the laboratory. After drying, the concentration of ions in the acid water samples increased progressively in oversaturation with respect to either gypsum, ferrohexahydrite or quenstedetite. The X-ray powder diffraction studies identified that the precipitated and evaporated materials after drying were well crystallized gypsum, ferrohexahydrite and quenstedetite. Diagnostic peaks used for identification of gypsum were the 7.65, 4.28, 3.03, 2.87 and 2.48$\AA$ peaks and those for ferrohexahydrite were the 5.46, 5.12, 4.89, 4.44, 4.05, 3.62, 3.46, 3.40, 3.20, 3.03, 2.94, 2.53, 2.28, 2.07, 1.88 and 1.86${\AA} peaks. The IR spectra with OH-stretching, deformation of $H_2O$and ${SO_4}^{2-}$stretching vibration include the existence of gypsum, ferrohexahydrite and quenstedetite in the precipitated and evaporite materials. In the SEM and EDS analysis for the evaporite material, gypsum with well-crystallized, acicular, and columnar form was distinctly observed.

• The Journal of Engineering Geology
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• v.21 no.2
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• pp.125-131
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• 2011

The discharge characteristics of the Seodo Mulgol Spring-the only groundwater-producing area in Dokdo-were evaluated by measurements of discharge rate and electrical conductivity (EC) on five occasions. The Seodo Mulgol Spring is fed by rainfall in upstream areas of the Mulgol cave, and the rainwater of the area moves down along cooling joints developed in trachyandesite II and trachyte, finally discharging at the Mulgol cave. The discharge rate of the Seodo Mulgol Spring varied from 1.12 to 7.02 $m^3/d$ during the study period and EC varied from 2,650 to 3,390 ${\mu}S/cm$, showing a sharp increase during heavy rainfall. The observed variations in discharge rate and EC at the Seodo Mulgol Spring are attributed to the relatively short distance between the recharge area and the Mulgol cave, and to the rapid movement of groundwater through columnar joints developed in trachyandesite II and trachyte. Additional discharge measurements, combined with precise rainfall data, are required at Dokdo to elucidate the discharge characteristics of the Seodo Mulgol Spring.

• Applied Microscopy
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• v.31 no.2
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• pp.207-214
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• 2001

Anatomy and ultrastructure of the modifeid Krana pattern have been studied in succulent Salsola collina Pall. Cylindrical leaves exhibited the Salsoloid Kranz type containing two layers of peripheral chlorenchyma that surrounded the water storage cells and vascular tissues. Small veins were also peripherally arranged, but mostly embedded in the vicinity of the inner chlorenchma without the orderly arrangement of the concentric layering of bundle sheath and mesophyll cells. The current study mainly focused on the chlorenchyma tissue abutting such minor veins. The outer columnar layer exhibited features similar to the characteristics of palisade mesophyll cells, while the inner cuboid layer to the bundle sheath cells of a typical $C_4$ Kranz pattern. Cellular components of the inner chlorenchyma were centripetal and numerous, but starch-laden chloroplasts were rudimentary in the thylakoidal system. The outer chlorenchyma demonstrated normally developed chloroplasts having well-stacked thylakoids and plastoglobuli. Branched and complicated plasmodesmata frequently occurred in thick interfaces of the two layers, implying the active movement of the photosynthates between them. The present data were mostly congruent with one of the structural features of the C4 subtypes , NADP-ME type, reported in the $C_4$ pattern. The Kranz pattern encountered in this Salsola probably has been directly related to the structural modification that occurred during a functional adaptation to the $C_4$ photosynthesis.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.264-265
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• 2010

최근, nanorod나 nanowire와 같은 1차원의 나노구조가 나노디바이스로 각광을 받고 있다. [1] 특히 InN는 3족 질화물 반도체 중 가장 작은 밴드갭 에너지와 뛰어난 수송 특성을 가지고 있어 나노디바이스로의 응용에 적합한 물질이다. [2] 그러나 InN는 큰 평형증기압을 가지므로 쉽게 인듐과 질소로 분해되는 특성이 있어 나노구조로의 성장이 쉽지 않음이 알려져 있다. [3] 최근 연구결과에 따르면, InN 나노구조는 금속 catalyst를 사용한 방법이나, 기판 위 패턴을 이용하여 성장하는 방법, 염소를 사용한 방법이 널리 쓰이고 있다. [4,5,6] 그러나 이 방법들은 의도치 않은 불순물의 원인이 되거나 다른 추가적인 과정을 필요로 한다는 문제점도 일부 가지고 있다. 본 연구에서는 catalyst-free 유기 금속 화학 증착법 (MOCVD)를 이용하여 $Al_2O_3$ (0001)면 위에 InN nanostructure를 성장하였다. InN nanostructure 성장 시 트리메틸인듐(TMIn)과 암모니아($NH_3$) 를 전구체로 사용하였으며, 캐리어 가스로는 질소를 사용하였다. 또한 모든 샘플의 성장시간은 60분으로 고정하였으나, 성장 시 온도의 의존성을 보기 위해 $680-710^{\circ}C$ 의 온도범위에서 성장을 진행하였다. 그 결과 InN는 본 실험에서 적용된 성장온도범위 내에서 온도가 증가함에 따라 초기에는 columnar구조로 성장된 박막의 형태에서 wall이 배열된 형태로 변화하며 결국 $710^{\circ}C$ 의 온도에서 nanorod로 성장하게 된다. 성장된 InN의 나노구조는 X-선 회절 측정법, 주사 전자 현미경 그리고 투과 전자 현미경을 이용하여 각각의 구조적 특성을 분석하였다. X-선 회절 측정법과 주사 전자 현미경을 통한 분석결과에서는 이들 nanorods가 대부분 c 방향으로 수직하게 정렬되어 있음을 확인 할 수 있었다. 또한, $690^{\circ}C$ 에서 60분간 성장된 InN의 wall 구조의 두께는 200 nm, 길이는 $2-2.5\;{\mu}m$로 관찰되었으며, $710^{\circ}C$에서 60분간 성장된 InN nanorod의 지름은 150 nm, 길이는 $3\;{\mu}m$ 정도로 관찰되었다. 이를 통하여 볼 때 성장 온도가 InN의 나노구조 형성 시 표면의 모폴로지변화에 중요한 변수로 작용함을 알 수 있다. 본 발표에서는 이러한 표면 형상 및 구조 변화가 성장온도에 따른 관계성을 가짐을 InN의 분해와 성장의 경쟁적인 관계에 의해 논의할 것이다.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.361-371
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• 1990

The present observations were focussed mainly on the morphological findings of the utero-vaginal(U-V) glands in normal laying domestic hens and the storage of cock spermatozoa in the U-V glands at various times after artificial insemination(AI). These domestic hens were assigned to three group of PMS-treated, GnRH-treated before last AI, and control group. The hens were sacrified at intervals of 1,3,7,12 and 19 days after AI. Histological sections of U-V junctions were prepared and the morphological structures of the U-V glands were observed and then were scored about the spermatozoa presence in the U-V gland. 1. The U-V glandular tubules were mostly unbranched with single columnar epithelium. Also these tubules were occassionally observed as one circular-rotated tubules or 2 to 3 branched convoluted tubules in special shapes. The numbers of the convoluted curves per tubule were $4.3{\pm}3.3$ and the ranges of convoluted curve number were straight to 16 curves. 2. The inside and outside diameters of the glandular tubules were $6.5{\pm}3.5{\mu}m$, and $35.2{\pm}4.7{\mu}m$, respectively, and the tubular lengths of the U-V glands were $219.3{\pm}115.7{\mu}m$. 3. Storaged spermatozoa in the U-V glands of all three group hens were intensively stained by hematoxylin, and packed in tight, longitudinally parallel bundles within the tubules. In addition, numbers of completely spermatozoa-filled glands were tend to increase or decrease in proportion to the numbers of partially spermatozoa-filled glands. Also U-V glands containing spermatozoa tend to be present collectively in the any zone of U-V junction. 4. In the control group, the numbers of glands containing spermatozoa in the hens at 1,3,7,12, and 19 days after AI were found to be 22.9, 33.3, 35.8, 8.6, and 0% respectively. 5. In the PMS-treated group, the numbers of glands containing spermatozoa in the hens at 1,3,7,12, and 19 days after AI were found to be 33.6, 29.7, 26.8, 8.2 and 0% respectively. 6. In the GnRH-treated group, the numbers of glands containing spermatozoa in the hens at 1,3,7,12, and 19 days after AI were found to be 19.7, 40.8, 20.4, and 0% respectively.

• Applied Microscopy
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• v.32 no.1
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• pp.57-66
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• 2002

The structures of sucker of two Cobiidae; Common freshwater goby and Triden goby were observed by light and electron microscopy. Scanning electron microscopy revealed the characteristic narrow ridges and grooves on the apical portion of sucker of Common freshwater goby, and hexagonal structures similar to a honeycomb representing the intercellular junctional area on the middle and basal portions. Some ridges were present on the epithelial surface on the middle and basal portions. The openings of several mucus-secreting cells were present between main epithelial cells. Light and transmission electron microscopy revealed the core of the fin; soft rays with a surrounding dense collagen fiber layer. Some loosely arranged fibers (collagen fiber) radiated toward the surface epithelium. The surface epithelium was cuboidal or columnar in shape. Scanning electron microscopy revealed the coiled irregular ridges and grooves, which was less developed and had sparser distribution than in Common freshwater goby, on the apical portion of sucker of Triden goby. The middle and basal portions had honeycomb structures as in Common freshwater goby. Fewer mucoussecreting cells were present. Light and transmission electron microscopy showed the core of soft rays, dense collagen fiber layer, however, the radiating fibers observed in the Common freshwater goby was rarely present. The sucker was thinner because the epithelium is squamous or polygonal in shape and rare presence of the radiating fibers.