• Korean journal of food and cookery science
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• v.11 no.3
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• pp.282-286
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• 1995

Physicochemical properties of Jeungpyun dough were analyzed during fermentation in the ranges of 0 to 10 hours. Solube Protein and total content of free amino acid of Jeungpyun dough were decreased at the early stage of fermentation, recording minimum value, 0.292 mg/g-dry matter and 13.31 mg/100g-dry matter at fermentation time, 2 hours and 4 hours respectively while they were increased since then. It was observed that, although few changes occurred at the early stage of fermentation, the height of peak on X-ray diffractogram was decreased somewhat and some disintegration of starch granule on scanning electron micrograph occurred slightly in dough samples of above 6 hours of fermentation time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.12
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• pp.1691-1701
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• 1998

Fly ash produced in coal combustion is a fine-grained material consisting mostly of spherical, glassy, and porous particles. A study on the formation mechanism of the fly ash from coal particles in the pulverized coal power plant is investigated with a physical, morphological, and chemical characteristic analysis of fly ash collected from the Samchonpo power plant. This study may contribute to the data base of domestic fly ash, the improvement of combustion efficiency, fouling phenomena and ash collection in the electrostatic precipitator. The physical property of fly ash is determined using a particle counter for the measurement of ash size distribution. Morphological characteristic of fly ash is performed using a scanning electron micrograph. The chemical components of fly ash are determined using an inductively coupled plasma emission spectrometry(ICP). The distribution of fly ash size was bi-modal and ranged from 12 to $19{\mu}m$ in mass median diameter. Exposure conditions of flue gas temperature and duration within the combustion zone of the boiler played an important role on the morphological properties of the fly ash such as shape, particle size and chemical components. The evolution of ash formation during pulverized coal combustion has revealed three major mechanisms by large particle formation due to break-up process, gas to particle conversion and growth by coagulation and agglomeration.

• Journal of the Korean institute of surface engineering
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• v.27 no.2
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• pp.99-108
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• 1994

Films of glass-ceramics $Li_2O-Al_2O_3-SiO_2$(LAS)system were prepared on substrate of an iron plate(SCP) by sol-gel technique using metal alkoxide such as Si$(OC_2H_5)_4$,Al$(OC_2H_9)_3$) and Ti$(OC_2H_6)_4$). Sol which was made by means of simple spray coating, on the substrate was hydrolyzed at 75~$80^{\circ}C$ in moisture cabinet (80~90 % humidity) to form the multicomponent gel. The films up to about 0.8~1.0$mu extrm{m}$ in thickness can be obtained by repeating operation, spraylongrightarrowhydrolysis and condensationlongrightarrowdryinglongrightarrowheating and crystallization at $700^{\circ}C$ for 3~5min. The far-infrared radiation spectra of the coated films on substrate were examined by FT-IR and of films was also observed by scanning electron micrograph technique. The thermal evaluation of the gel-film is followed by TG/DTA measurements. The structure evaluation is followedd X-ray diffraction. These results suggest that this process is applicable to far-infrared radiat at thin film technique.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.743-746
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• 2000

The possiblity of sepiae os as a calcium supplement in food was studied. Elementary contents of sepiae os were as follows; Ca 53.254%, O 26.781%, Na 14.905%, Cl 4.37%, Sr 0.507%, P 0.068% and Si 0.051%, respectively. Most of calcium in sepiae os was present as a form of CaCO3. Sruface area of sepiae os was found as 386 m2/g, and scanning electron micrograph showed sepiae os has multilayer struture. Buffering capacity of sepiae os that of CaCO3. With above results, sepiae os can be used as a calcium supplement in food with good chacterateristics.

• Current Photovoltaic Research
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• v.1 no.2
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• pp.97-102
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• 2013

Aluminum-doped zinc oxide (AZO) thin films were prepared by dc magnetron sputtering at room temperature and the effect of heat treatment on the structural, electrical and optical properties of the films were examined. As the annealing temperature and time increased, the resistivity decreased and the transmittance improved. All AZO films had c-axis oriented (002) plane of ZnO, regardless of the annealing process employed. As the annealing temperature and time increased, the crystallinity of AZO thin films increased due to the formation of a new ZnO phase in which Al was substituted for Zn. However, at the high annealing temperature of $400^{\circ}C$, the resistivity of the films increased via separation of Zn and Al from ZnO phase due to their low melting points. X-ray diffraction, field emission scanning electron micrograph and Hall effect measurement confirmed the formation of uniformly distributed new grains of ZnO substituted with Al. The variation of Al contents in AZO films was shown to be the primary factor for the changes in resistivity and carrier concentration of the films.

• Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.7.1-7.6
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• 2016

In nature, marine mussels (Mytilus edulis) suffer less fouling colonization on the newly formed sides of their shells. Using settlement assays with algal spores of Porphyra suborbiculata, we determined that spore attachment and germination on the periostracum decreased to 36.8 and 3.3 %, respectively. Additionally, the spore settlement was considerably diminished by periostracum dichloromethane extracts containing 19 % oleamide, a major antifouling compound. A scanning electron micrograph of the surface revealed a regular ripple structure with approximately $1.4{\mu}m$ between ripples. Based on these results, mussel periostraca or their associated biomimetic materials may become environmentally friendly, antifouling agents for preventing the settlement of soft foulants.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.491-495
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• 1999

$Ni_{0.2}V_2O_5$ aerogel (ARG) was synthesized via the sol gel method and has been studied with an emphasis on the characterization of its electrochemical properties. ARG appear to be amorphous layered material. Electron micrograph revealed that entangled fibrous textures has been grown to form anisotropic corrugated sheets. Several sites for the Li ion intercalation exist between the layers of ARG and average cell potential was 3.1 V vs $Li/Li^+$ Th charge transfer resistance increases 3 to 4 times as lithium composition increases, but the interphase resistance remains almost constant regardless of the lithium composition in thc ARG.

• Journal of fish pathology
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• v.16 no.2
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• pp.81-90
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• 2003

High mortality with signs similar to viral haemorrhagic septicemia (VHS) such as severe haemorrhages in the skin, muscle and air bladder occurred in the farmed adult rainbow trout, Oncorhynchus mykiss, in Ku-mi and Je-chun area in Korea. The isolates were neutralized by an antiserum against IHNV but not by antisera against VHSV. Electron micrograph of an ultrathin section showed large numbers of bullet-shaped virus particles. The newly isolated rhabdovirus was composed of five structural proteins. In the western blot analysis Ihe anti-DiNV serum strongly reacted with G. N and MI protein. The cumulative mortalities of RTK infected rainbow trout (10-12cm.9-12g) with $10^{3.5}\;and\;10^{1.5}TCID_{50}/m{\ell}$ were 80% and 30%. respectiveIy_ RTJ infected fish showed 50% mortality by infection with $10^{3.5}TCID_{50}/m{\ell}$. Control group and IHNVChAb exhibited no mortality. From these results, the viruses were identified lHNV although diseased fish showed similar sign. with VHS and caused high mortality in large-sized fish.

• Journal of Welding and Joining
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• v.19 no.1
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• pp.40-48
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• 2001

An ultrasonic test method, as a nondestructive test is applied to ensure the clad interface quality assessment. According to the reference codes and standards, not only korea Industrial Standard(KS) but also American Society for Testing and Materials (ASTM) Standard, ultrasonic examination procedures use the pulse-echo, A-scan, back reflection signal drop method and/or side drilled reference hole used to establish the acceptance criteria of clad material test. But the variety of bonding materials and sizes makes it difficult to produce the reference blocks, or thus the criteria. In order to overcome these practical difficulties, new ultrasonic testing criterion is suggested. In this new method, the theoretical interface reflection signal amplitude level is calculated and suggested as an acceptance criteria with the back reflection signal set to 100% FSH(Full Screen Height) which is based on acoustic impedance mismatch at the clad interface for the explosive clad ultrasonic inspection. Applicability of suggested criterion, for the explosive clad Fe-Naval Brass with different bonding quality is confirmed to the pre-existed KS and ASTM specifications and verified by using SEM (Seanning Electron Microscope) micrograph. The results obtained by the suggested method is more conservative than the results according to the KS B 0234 and ASTM A 578 specifications The suggested method could be applicable to any other combination of explosive clad ultrasonic inspection.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1016-1020
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• 2002

Ru thin films were etched using CF/$_4$O$_2$ plasma in an ICP (inductively coupled plasma etching) system. The maximum etch rate of Ru thin films was 168 nm/min at a CF$_4$/O$_2$ gas mixing ratio of 10 %. The selectivity of SiO$_2$ over Ru was 1.3. From the OES (optical emission spectroscopy) analysis, the optical emission intensity of the O radical had a maximum value at 10% CF$_4$ gas concentration and drcrease with further addition of CF4 gas, but etch slope was enhanced. From XPS (x-ray photoelectron spectroscopy) analysis, the surface of the etched Ru thin film in CF$_4$/O$_2$ chemistry shows Ru-F bonds by the chemical reaction of Ru and F. RuF$_{x}$ compounds were suggested as a surface passivation layer that reduces the chemical reactions between Ru and O radicals. From a FE-SEM (field emission scanning electron microscope) micrograph, we had an almost perpendicular taper angle of 89$^{\circ}$.>.