• The International Journal of Costume Culture
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• v.7 no.1
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• pp.40-47
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• 2004

The purpose of this research was to examine the degradation rate of alizarin in accelerated degradation conditions using the GC-MS quantitative analysis. Alizarin dye solution (2.5 x 10/sup -3/ M conc.) were kept in 150℃ oven for total of 7 days and the degradation rate was examined each day. 2.5 × 10/sup -4/M conc. alizarin dye solution was mixed with H₂O₂ according to [H₂O₂]/[dye] ratio 40 and were kept under 365㎚ UV for 2 hours, analyzed after 0, 30, 60, 90, 120min using the GC-MS. Gas chromatogram showed alizarin peak at 9.96 - 10.13 min. retention time range and residual peaks in the wide range from 9.6 to 11.1 min. Oven degradation exhibited an initial decrease in the amount of alizarin, which was followed by increasing amount in 4/sup th/ day. The decrease in the alizarin was significantly shown by the 7/sup th/ day. Same pattern was also observed in the H₂O₂/UV/O₂ degradation samples and was verified ed by the UV-VIS spectra. The differences in the amount of alizarin between 1/sup st/ day and 4/sup th/ day samples, 4/sup th/ day and 7/sup th/ day samples, and Control and 7/sup th/ day samples of the oven degradation were significant at alpha .20.

• Textile Coloration and Finishing
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• v.30 no.1
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• pp.29-37
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• 2018

Cotton has no adsorption ability for the cationic dye and heavy metal but, if anionized cotton can be made, it will be possible. In this study, to enable the anionisation of cotton fabric, it was modified using sodium vinylsolfonate(SV) as the anionisation reagent, employing a pad-dry-cure(PDC) technique. The effects of curing time, treatment concentrations of urea, sodium hydroxide and SV on the weight increase were experimented and then, the physical characterizations of sulfoethyl cotton(SEC) depending on the finishing conditions were estimated, thus the application possibility of SV as anionisation reagent was investigated. It was not much changed by anionisation except wrinkle recovery. And the structure of SEC was elucidated by Raman and NMR spectoscopy. The feasibility of using Raman and NMR spectroscopy with the band at $1,043cm^{-1}$, and 50.5ppm, respectively as marker band to determine sulfoethyl group of SEC was reported. The total degree of SV substitution(DSV) was determined via elemental analysis. SEC with diverse total DSV up to 0.066 was obtained. In the thermal decomposition(pyrolysis) by DSC, it can be found that the pyrolysis temperature was about $30^{\circ}C$ lower than that of non-treated cotton fabric.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.142-148
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• 2009

The direct injection(DI) diesel engine has become a prime candidate for future transportation needs because of its high thermal efficiency. However, nitrogen oxides(NOx) increase in the local high temperature regions and particulate matter (PM) increases in the diffusion flame region within diesel combustion. Therefore, the demand for developing a suitable after treatment device has been increased. NOx absorbing catalysts are based on the concept of NOx storage and release making it possible to reduce NOx emission in net oxidizing gas conditions. This De-NOx system, called the LNT(Lean NOx Trap) catalyst, absorbs NOx in lean exhaust gas conditions and release it in rich conditions. This technology can give high NOx conversion efficiency, but the right amount of reducing agent should be supplied into the catalytic converter at the right time. In this research, a performance characteristics of LNT with a hydrogen enriched gas as a reductant was examined and strategies of controlling the injection and rich exhaust gas condition were studied. The NOx reduction efficiency is closely connected to the injection timing and duration of reductant. LNT can reduce NOx efficiently with only 1 % fuel penalty.

• Journal of the Korean Society of Safety
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• v.17 no.4
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• pp.101-109
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• 2002

The electrical properties of polyethylene are changed by the superstructure. Such crystalline polymer as polyethylene or polypropylene changes crystallinity and products spherulite or trans-crystal when it is cooled slowly. In this study, after thermal treatment of LDPE at 100[${circ}C$], in silicone oil for an hour, we made specimens in order of slow cooling, water cooling, quenching according to cooling speed. Also, to study the influence of electrical properties due to the superstructure change, we analyzed physical properties and performed dielectric breakdown experiments using DC and impulse voltage Moreover we measured space charges in bulk using Laser Induced Pressure Pulse(LIPP) method. Trap level of specimen is 0.064[eV] at the low temperature region 0.31[eV] at the high temperature region in DC dielectric strength, 0.03[eV] at the low temperature region 0.0925[eV] at the high temperature region in impulse dielectric strength. As its result shows that the quantity of charges induced from the electrode surface increases with applied voltage time, and the distribution of space charges in samples increases the quantity of charges in proportion to applied voltage.

• Journal of Powder Materials
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• v.13 no.3 s.56
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• pp.192-198
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• 2006

The nanostructured cerium oxide powders were synthesized by spray thermal decomposition process for the use as the raw materials of resistive oxygen sensor. The synthesis routes consisted of 1) spray drying of water based organic solution made from cerium nitrate hydrate ($Ce(NO_3){_3}6H_2O$) and 2) heat treatment of spray dried precursor powders at $400^{\circ}C$ in air atmosphere to remove the volatile components and identically to oxidize the cerium component. The produced powders have shown the loose structure agglomerated with extremely fine cerium oxide particles with about 15 nm and very high specific surface area ($110m^2/g$). The oxygen sensitivity, n ($Log{\propto}Log (P_{O2}/P^o)^{-n}$ and the response time, $t_{90}$ measured at $600^{\circ}C$ in the sample sintered at $1000^{\circ}C$, were about 0.25 and 3 seconds, respectively, which had much higher performances than those known in micron or $100{\sim}200nm$ sized sensors.

• Journal of Oriental Neuropsychiatry
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• v.33 no.1
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• pp.113-122
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• 2022

Objectives: To report the effect of Korean medicine on a patient with insomnia from severe hot flashes. Methods: The patient suffered from extreme hot flashes for months. Symptoms were so severe that the patient attempted suicide. After starting psychiatric medication, symptoms persisted and hospitalization began. During hospitalization, herbal medicine, acupuncture, and psychotherapy were conducted. For evaluating therapeutical effect, Digital Infrared Thermal Imaging was performed twice during the treatment process. It was divided into major facial area and back area. The facial area was divided into two small units to measure the difference in temperature between two points. The back area was measured in the same way. Results: The temperature difference between the two points decreased over time and the patient's subjective symptoms reduced. Conclusions: Korean medicine therapy can improve symptoms of patients with insomnia accompanied by hot flashes.

• Journal of ILASS-Korea
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• v.17 no.3
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• pp.146-151
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• 2012

This study was primarily focused on the experimental comparison of the particle emission characteristics for heavy duty engine. PM and particle number from various heavy duty engines and DPF type were analyzed with a golden particle measurement system recommended by the Particle Measurement Program. And the repeatability and reproducibility between test mode was analyzed. This study was conducted for the experimental comparison on particulate emission characteristics between the European and World-Harmonized test cycles for a heavy-duty diesel engine. To verify the particulate mass and particle number concentrations from various operating modes, ETC/ESC and WHTC/WHSC, both of which will be enacted in Euro VI emission legislation, were evaluated. Real-time particle formation of the transient cycles ETC and WHTC were strongly correlated with engine operating conditions and after-treatment device temperature. A higher particle number concentration during the ESC mode was ascribed to passive DPF regeneration and the thermal release of low volatile particles at high exhaust temperature conditions.

• Journal of Yeungnam Medical Science
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• v.41 no.4
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• pp.279-287
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• 2024

Atrial fibrillation (AF) is the most common sustained tachyarrhythmia and its increasing prevalence has resulted in a growing health-care burden. A recent landmark randomized trial, the EAST-AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial), highlighted the importance of early rhythm control in AF, which was previously underemphasized. Rhythm control therapy includes antiarrhythmic drugs, direct-current cardioversion, and catheter ablation. Currently, catheter ablation is indicated for patients with AF who are either refractory or intolerant to antiarrhythmic drugs or who exhibit decreased left ventricular systolic function. Catheter ablation can be categorized according to the energy source used, including radiofrequency ablation (RFA), cryoablation, laser ablation, and the recently emerging pulsed field ablation (PFA). Catheter ablation techniques can also be divided into the point-by-point ablation method, which ablates the pulmonary vein (PV) antrum one point at a time, and the single-shot technique, which uses a spherical catheter to ablate the PV antrum in a single application. PFA is known to be applicable to both point-by-point and single-shot techniques and is expected to be promising owing to its tissue specificity, resulting in less collateral damage than catheter ablation involving thermal energy, such as RFA and cryoablation. In this review, we aimed to outline catheter ablation for rhythm control in AF by reviewing previous studies.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.446-449
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• 2005

Two single-magnetron heating systems (SM-HS), each with a helical glass heat exchanger and a cylindrical cavity, were combined to make a two-magnetron-in-series heating system (2MS-HS) in order to increase the heating capacity. A comparison using water showed that the heating performance of the 2MS-HS was increased by two-fold as compared to that of the SM-HS, resulting in energy saving of 7.0% in 2MS-HS. Pasteurization test of 2MS-HS conducted with model food (LB broth contaminated with Bacillus subtilis) showed two-fold higher treatment capacity compared to SM-HS. Relationships between outlet temperature of the processed food, flow rate, and residence time in the 2MS-HS were established for water. Optimum pasteurization capacity was 17 s, $73^{\circ}C$, at flow rate of 280 ml/min. The 2MS-HS could be applied to the small-scale pasteurization of liquid food.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.408-412
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• 2008

Determining the elution of water-soluble substances from herbal teas is an important factor in their efficient use in terms of taste, perfume, and content of health-related components. The antioxidant activity and content of catechins in commercial Chrysanthemum indicum (gamguk) teas were determined for optimum elution conditions. The water extract of gamguk teas did not differ significantly in yield compared to methanol extracts and showed stronger antioxidant activity. Catechin contents in gamguk teas were 8-18% of the extracts when individual peaks in high-performance liquid chromatography analysis were compared to standard catechin peaks. Gamguk teas exhibited faster release of antioxidants, and the antioxidant activity was positively correlated with the thermal treatments. Gukhwacha (GC) was the best tea for rapid release (30 sec) of antioxidants with the $50^{\circ}C$ treatment, whereas antioxidants in other teas were relatively slower released.