• Ceramist
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• v.16 no.3
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• pp.35-43
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• 2013

• Ceramist
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• v.16 no.3
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• pp.54-60
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• 2013

• Polymer Science and Technology
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• v.11 no.5
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• pp.671-676
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• 2000

• Food Science and Preservation
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• v.16 no.6
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• pp.875-883
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• 2009

We investigated the effects of manufacturing method on the quality of beef jerky using electron micrography. Six types of beef jerky were prepared by the addition of sugar (A), licorice (B), one of three kinds of spice extract (clove: C, fennel fruit: D, and Chungyang green pepper extract: E), or a mixture of all spice extracts (F). Microstructural changes in beef jerky during preparation by drying, with respect to drying method and the nature of the added spice extract, were observed by scanning electron micrography (SEM) and transmission electron micrography (TEM). The latter technique showed that the microstructure of fresh meat showed actin and myosin in myofibril lines, and also mitochondria and inner membranes. Beef muscle structure was broken at many myofibril lines and decomposition of inner membrane material was evident after seasoning. SEM of air-blast dried beef jerky with added medicinal herb extracts showed both large spaces and regular myofibrils, whereas hot air-dried beef jerky had no spaces and the muscle myofibrils were still evident. After review of all available micrographs from SEM and TEM, we concluded that use of medicinal herb extracts could be helpful in preserving the muscle myofibril structure during drying, and the air-blast drying method is recommended to optimize the textural quality characteristics of beef jerky.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.436-443
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• 2017

Recently, the development of new energy technologies has become a hot topic due to problems,such as global warming. Unlike renewable energy technologies, such as solar energy generation, solar power, and wind power, which are optimized to achieve medium or above output power, the output power of energy harvesting technology is very small and has not received much attention. On the other hand, as the mobile industry has been revitalized recently, the utility of energy harvesting technology has been reevaluated. In addition, the technology of tracking the maximum power point has been actively researched. This paper proposes a new MPPT(Maximum Power Point Tracking) control method for a TEM(thermoelectric module) for load resistance. The V-I curve characteristics and internal resistance of TEM were analyzed and the conventional MPPT control methods were compared. The P&O(Perturbation and Observation) control method is more accurate, but it is less economical than the CV (Constant Voltage)control method because it usestwo sensors to measure the voltage and current source. The CV control method is superior to the P&O control method in economic aspects because it uses only one voltage sensor but the MPP is not matched precisely. In this paper, a method wasdesigned to track the MPP of TEM combining the advantages of the two control method. The proposed MPPT control method wasverified by PSIM simulation and H/W implementation.

• Korean Journal of Microbiology
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• v.46 no.1
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• pp.38-45
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• 2010

The study performed to identify the type of ESBL against strains which are producing extendedspectrum ${\beta}$-lactamases and isolated from sewage in Suyeong sewage disposal plant, Busan Environmental Corporation. By the standard activated sludge method, Suyeong sewage disposal plant purify living and lavatory sewage gathering from the northeast Busan and the facility purify total 550,000 tons of living sewage disposal a day. 14 strains were isolated by double disk synergy test and the third generation cepha-antibiotics test. Indole, methyl-red, Voges-Proskauer, Simmon's citrate, decarboxylasedihydrolase and sugar-fermentation tests identified as Klebsiella pneumoniae (n=4) and Escherichia coli (n=10). Plasmid-mediated transmission test against isolated 14 strains proved 11 strains transmitted resistance to recipient E. coli J53 (sodium $azide^R$, $ceftazidime^S$). 9 strains of conjugant were expressed ESBL genes transferred from parental strain but 2 conjugants did not expressed. The type of ESBL from each strain was determined by isoelectric focusing points, DNA and amino acids sequencing. The results indicated that the types of ESBL transmitted to recipient E. coli J53 were TEM-1, the parental TEM type and SHV-12 type.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.4
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• pp.311-316
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• 2008

In this study, we have investigated the effects of ultraviolet (UV) irradiation on the external and internal structure of human hair. For changes in morphological and chemical structure of UV-exposed hair, we utilized several microscopic techniques such as scanning electron microscope (SEM), transmission electron microscope (TEM), confocal laser scanning microscope (CLSM), and etc. The SEM showed the scales of UV-exposed hair appeared to be rough and bulkier because of chemical oxidation during UV irradiation. Small bulgy area of UV_exposed hair surface was appeared as a result of the decomposition in cysteic acid. In the TEM picture the UV-exposed hair showed the cleaved aperture of hair and destruction of melanin granules. Three dimensional topographical images were obtained by using CLSM. In the optical single section, high fluorescent intensity appeared in virgin hair. In the case of UV-exposed hair, low fluorescence intensity appeared. This means the aromatic amino acids in virgin hair were more abundant than UV-exposed hair.

• Korean Journal of Materials Research
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• v.11 no.8
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• pp.671-678
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• 2001

All solid-state thin film micro supercapacitor, which consists of $RuO_2$/LiPON/$RuO_2$ multi layer structure, was fabricated on Pt/Ti/Si substrate using a $RuO_2$ electrode. Bottom $RuO_2$ electrode was grown by dc reactive sputtering system with increasing $O_2/[Ar+O_2]$ ratio at room temperature, and a LiPON electrolyte film was subsequently deposited on the bottom $RuO_2$ electrode at pure nitrogen ambient by rf reactive sputtering system. Room temperature charge-discharge measurements based on a symmetric $RuO_2$/LiPON/$RuO_2$ structure clearly demonstrates the cyclibility dependence on the microstructure of the $RuO_2$ electrode. Using both glancing angle x-ray diffraction (GXRD) and transmission electron microscopy (TEM) analysis, it was found that the microstructure of the $RuO_2$ electrode was dependent on the oxygen flow ratio. In addition, x- ray photoelectron spectroscopy(XPS) examination shows that the Ru-O binding energy is affected by increasing oxygen flow ratio. Furthermore, TEM and AES depth profile analysis after cycling demonstrates that the interface layer formed by interfacial reaction between LiPON and $RuO_2$ act as a main factor in the degradation of the cyclibility of the thin film micro-supercapacitor.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.658-663
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• 2007

Bacillus thuringiensis is a well-known species of entomophathogenic bacteria that is widely used as a biopesticide against many insect pests. It produces parasporal crystals ($\delta$-endotoxin) and endospores during sporulation. In this report, the $\delta$-endotoxin produced by Bacillus thuringiensis BT-1 and BT-2 were characterized by Scanning Electron Microscope(SEM), Transmission Electron Microscope(TEM), SDS-PACE, and solubilization activity by alkaline solution. BT-1, BT-2 were cultured in the GBY medium, and the $\delta$-endotoxin of them was purified with discontinuous sucrose density gradient centrifugation. Their $\delta$-endotoxin was observed by SEM and TEM. Morphologically, the $\delta$-endotoxin of BT-1 was a square and flat type, whose size was $1.73{\mu}m{\times}0.7{\mu}m$, and the $\delta$-endotoxin of the BT-2 was spherical form whose size was $1.1{\mu}m{\times}0.9{\mu}m$ determined by SEM and TEM. The $\delta$-endotoxin of the BT-1 was composed of 28 kDa and 21 kDa, however, it of the BT-2 was composed of 50 kDa, 35 kDa, and 22 kDa bands determined by SDS-PACE. The purified crystals of BT-1 and BT-2 were dissolved gradually in alkaline solution as time goes by, and it was perfectly dissolved after 3 hours. It is supposed that the $\delta$-endotoxin of crystal was converted to a state of activation in the course of time in the intestines of insect.

• Economic and Environmental Geology
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• v.57 no.5
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• pp.563-575
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• 2024

In Korea, talc, vermiculite, sepiolite, and serpentine were designated as minerals likely to contain asbestos (MLCA) according to the Ministry of Environment (Asbestos Safety Management Act). The asbestos content in commercial products made of MLCA must not exceed 0.1 %. In this study, mineralogical analyses using PLM, XRD, and TEM-EDS were used to characterize the presence, content, and morphological characteristics of asbestos in MLCA-containing commercial products. A total of 28 samples were analyzed, including 18 cosmetics containing talc, 5 fertilizers containing vermiculite, 2 pet sanitary products containing sepiolite, and 3 accessories containing serpentine. All samples were heated at 450 ℃ for 6 hours to remove organic matter prior to XRD and PLM analyses according to the Ministry of Environment guidelines. Additionally, the presence and morphology of elongated mineral particles (EMPs) were investigated using TEM-EDS analysis according to the recently revised asbestos analysis method (FDA-2020-N-0025) by the US FDA. The analyses showed that no asbestos was detected in both talc-containing cosmetics and sepiolite-containing products, but actinolite asbestos was found (<0.25 %) in vermiculite-containing fertilizers and chrysotile was found (<0.25 %) in decorative serpentine stones. In TEM-EDS analysis, multiple columnar/fibrous particles measuring 0.5 ㎛ or more in length were observed in talc-containing products, and short chrysotile fibers were observed in bracelets containing serpentine. Therefore, these results indicated that the MLCA-containing products that come into direct contact with the human body would require management through precise inspection and continuous monitoring considering EMPs of 5 ㎛ or less. Furthermore, TEM-EDS for asbestos analysis indicated that it could overcome the detection limits of XRD and PLM analyses for short or thin asbestos fibers, thereby improving the precision and accuracy of asbestos analysis.