• Journal of the Korean Electrochemical Society
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• v.10 no.1
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• pp.48-51
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• 2007

In order to investigate the effects of particle size and specific surface area(BET area) of spinel powder, $LiMn_2O_4$ were synthesized using metal oxide precursor by co-precipitation method(CoP) and solid state reaction (SSR) .X-ray diffraction(XRD) patterns revealed that the both prepared powder has a well developed spinel structure with Fd3m space group. The $LiMn_2O_4$ prepared by co-precipitation showed spherical morphology with narrow size distribution. However, the $LiMn_2O_4$ prepared by solid state reaction showed relatively smaller particles with irregular shape. The measured BET areas of the powers are $0.8m^2g^{-1}$ (CoP) and $3.6m^2g^{-1}$(SSR). The electrochemical performance of the Prepared $LiMn_2O_4$ powders was evaluated using coin type cells(CR2032) at elevated temperature ($55^{\circ}C$). The $LiMn_2O_4$ prepared by co-precipitation showed the better cycling performance(82.3%capacity retention at $50^{th}$ cycle) than that of the $LiMn_2O_4$(68.3%) prepared by solid state reaction at elevated temperature.

• Clean Technology
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• v.26 no.2
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• pp.96-101
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• 2020

In this paper, the commercial feasibility of trigeneration, producing heat, power, and hydrogen (CHHP) and using biogas derived from macroalgae (i.e., seaweed biomass feedstock), are investigated. For this purpose, a commercial scale trigeneration process, consisting of three MW solid oxide fuel cells (SOFCs), gas turbine, and organic Rankine cycle, is designed conceptually and simulated using Aspen plus, a commercial process simulator. To produce hydrogen, a solid oxide fuel cell system is re-designed by the removal of after-burner and the addition of a water-gas shift reactor. The cost of each unit operation equipment in the process is estimated through the calculated heat and mass balances from simulation, with the techno-economic analysis following through. The designed CHHP process produces 2.3 MW of net power and 50 kg hr^-1 of hydrogen with an efficiency of 37% using 2 ton hr^-1 of biogas from 3.47 ton hr^-1 (dry basis) of brown algae as feedstock. Based on these results, a realistic scenario is evaluated economically and the breakeven electricity selling price (BESP) is calculated. The calculated BESP is ¢10.45 kWh^-1, which is comparable to or better than the conventional power generation. This means that the CHHP process based on SOFC can be a viable alternative when the technical targets on SOFC are reached.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.10
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• pp.1009-1015
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• 2006

The elcetrodewatering filter press(EDFP) which had anode and cathod plates to be set between filter plates was built for reducing the waterworks sludge and improving performance of dewatering equipment. Several tests to compare the dewaterability with conventional mechanical filter press dewatering(MDEP) and EDFP was conducted through this equipment. As test results, filtration amount discharged from EDFP measured 43.2 kg which increased against MDFP, and cake weight measured 4 kg which was two times against MDFP. The water content of dewatered cake from EDFP was 55wt% and dewatering velocity was 2.3 $kg/m^2{\cdot}cycle$. This water content decrease 20% and dewatering velocity increased 30% with compare to the MDFP. That is to say, EDFP constructed from electrodewatering mechanism increase filtrate discharging amount, which make dewatering velocity increase and produce the low water content dewatered cake against MDFP. Energy consumption of EDFP is analysed to 400 kwh/DS ton. The results to analysis the economical aspect considering the power consumption and the handling cost decline as sludge volume reduction due to producing the low water content cake showed that expenses to handle sludge of 1 ton by dry solid base cut down on 20,000 won. If considering several test aspects, it was analysed that EDFP was excellent in the side of performance as well as economical suitability.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.29-35
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• 2014

Purpose : This study has already started commercial Gated RapidArc automation equipment which was not previously in the Gated radiation therapy can be performed simultaneously with the VMAT Gated RapidArc radiation therapy to the accuracy of the analysis to evaluate the usability, Amplitude mode applied to the patient. Materials and Methods : The analysis of the distribution of radiation dose equivalent quality solid water phantom and GafChromic film was used Film QA film analysis program using the Gamma factor (3%, 3 mm). Three-dimensional dose distribution in order to check the accuracy of Matrixx dosimetry equipment and Compass was used for dose analysis program. Periodic breathing synchronized with solid phantom signals Phantom 4D Phantom and Varian RPM was created by breathing synchronized system, free breathing and breath holding at each of the dose distribution was analyzed. In order to apply to four patients from February 2013 to August 2013 with liver cancer targets enough to get a picture of 4DCT respiratory cycle and then patients are pratice to meet patient's breathing cycle phase mode using the patient eye goggles to see the pattern of the respiratory cycle to be able to follow exactly in a while 4DCT images were acquired. Gated RapidArc treatment Amplitude mode in order to create the breathing cycle breathing performed three times, and then at intervals of 40% to 60% 5-6 seconds and breathing exercises that can not stand (Fig. 5), 40% While they are treated 60% in the interval Beam On hold your breath when you press the button in a way that was treated with semi-automatic. Results : Non-respiratory and respiratory rotational intensity modulated radiation therapy technique absolute calculation dose of using computerized treatment plan were shown a difference of less than 1%, the difference between treatment technique was also less than 1%. Gamma (3%, 3 mm) and showed 99% agreement, each organ-specific dose difference were generally greater than 95% agreement. The rotational intensity modulated radiation therapy, respiratory synchronized to the respiratory cycle created Amplitude mode and the actual patient's breathing cycle could be seen that a good agreement. Conclusion : When you are treated Non-respiratory and respiratory method between volumetric intensity modulated radiation therapy rotation of the absolute dose and dose distribution showed a very good agreement. This breathing technique tuning volumetric intensity modulated radiation therapy using a rotary moving along the thoracic or abdominal breathing can be applied to the treatment of tumors is considered. The actual treatment of patients through the goggles of the respiratory cycle to create Amplitude mode Gated RapidArc treatment equipment that does not automatically apply to the results about 5-6 seconds stopped breathing in breathing synchronized rotary volumetric intensity modulated radiation therapy facilitate could see complement.

• Journal of the Korean Ceramic Society
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• v.42 no.9 s.280
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• pp.631-636
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• 2005

$LiNi_{1-y}Ga_yO_2$ (y = 0.005, 0.010, 0.025, 0.050, and 0.100) were synthesized by the solid-state reaction method after mechanical mixing, and their_electrochemical properties were investigated. All the $LiNi_{1-y}Ga_yO_2$ (y=0.005, 0.010, 0.025, 0.050, and 0.100) samples had the R3m structure. The sample with y = 0.025 showed the largest first discharge capacity (131.4 mAh/g) and good cycling performance [discharge capacity 117.5 mAh/g ($89.4{\%}$ of the first discharge capacity) at the 20th cycle]. The first discharge capacity decreased as the value of y increased. The samples with y = 0.010 and y = 0.005 had small R-factor but their cycling performance was worse than that of the sample with y = 0.025. All the $LiNi_{1-y}Ga_yO_2$ samples had smaller discharge capacities than $LiNiO_2$, but their cycling performances were better than that of $LiNiO_2$.

• Clinical and Experimental Reproductive Medicine
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• v.9 no.1_2
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• pp.43-53
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• 1982

여성의 난소기능은 뇨중 Oestrone-3-glucuronide를 간편한 solid-phase 의 화학발광성 면역학적 측정법 (Chemiluminescence Imrnunoassay(CIA) 에 의하여 그 기능이 탐지될 수 있다. Oestrone-3-g1ucuronyl-6-bovine serum albumine에 대한 antiserum의 IgG fraction은 polystyrene 실험관벽에 흡착시켰으며, 항원으로서는 est r one-3- gl ucuronyI-6-aminoethyl-ethyl-isoluminol 을 항원 (antigen) 에 labeI 시킨 것이다. 시험 대상물인 뇨는 매일아침뇨(early morning urine) 을 희석 (1:1000 V/V)한 후 100mcl 를 취하여 이를 각기 이중분석액으로 택하였다. 시험관 내에서 결합반응 (1 hour at $4^{\circ}C)이 일어난 후에는 시험관내의 액체를 전부 흡입 폐기시켰으며, 항체반응이 일어난 후 ( antibody-bound fraction )에는 완충액 (400mcl)으로 한번 세척시켰다. 그후 염화수산화물(2N , 200mcl)을 가지고 $22^{\circ}C$에 60 분간 방치 혼합케 한 후 효소(microperoxidase) 와 과산화수소를 가하면서 산화작용에서 발생되는 발광양을 10초동안 측정하여 그 결과를 분석하였다. 위에 기술한 분석방법을 평가하면 다음과 같은 결론을 얻었다. Calibration curve sensitivity$3.12{\pm}0.75$ PG/tube ($mean{\pm}SD$)였고, lntra-assay precision(CV%) 9.52 (20 replicates;$38.4{\pm}3.66$nmol/1) 와 8.81 (15 replicates; $102.4{\pm}8.82$nmol/1)였다. Inter-assay precision(CV%) 은 11.9 (mean of 4 pools-7.03, 23.16, 52.11 과 117.53 nmol/1)로 2개월 동안에 걸쳐 시행되었고, 평균 비이어스(mean bias)는 -0.78 로 28에서 448 nmol 범위로서 매일아침 "뇨"의 차이분(different aliquots)은 좋은 결과를 얻었다. 건강한 여성으로부터 채취된 뇨중 Oestrone-3-glucuronide 의 농도(nmol/1)를 보면 월경주기의 여포기와 배난기 및 황체기에 있어서 각기 $40.2{\pm}9.9$ , $102.3{\pm}39.4$와 $84.3{\pm}13.3$nmol/1였다. 이와같은 결과는 동일한 검사뇨를 방사면역학적 방법(RIA)으로 측정 (6 menstrual cycle)한 결과와 유사한 측정치를 얻으므로서 간편하고 진보된 좋은 방법중의 하나라고 사료되는바이다.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2883-2888
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• 2014

Background: Realgar which contains arsenic components has been used in traditional Chinese medicine (TCM) as an anticancer drug. However, neither Realgar nor its formula are soluble in water. As a result, high dose of Realgar has to be administered to achieve an effective blood medicine concentration, and this is associated with adverse side effects. The objective of the present study was to increase the solubility of a formula using hydrometallurgy technology as well as investigating its effects on in vitro and in vivo cell proliferation and apoptosis in Sarcoma-180 cell line. Materials and Methods: Antiproliferative activity of Realgar Bioleaching Solution (RBS) was evaluated by MTT assay. Further, effects of RBS on cell proliferation and apoptosis were studied using flow cytometry and transmission electron microscopy. Kunming mice were administered RBS in vivo, where arsenic specifically targeted solid tumors. Results: The results indicated that RBS extract potently inhibited the tumor growth of Sarcoma-180 cell line in a dose-dependent manner. Flow cytometry and transmission electron microscopy further indicated that RBS significantly induced cell apoptosis through the inhibition of cell cycle pathway in a dose-dependent manner. Further, on RBS administration to mice, arsenic was specifically targeted to solid tumor.s Conclusions: RBS could substitute for traditional Realgar or its formula to work as a potent tool in cancer treatment.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.125-137
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• 1989

To check technical improvement in the soundness and strength of 12% Cr steel rotor, a 25 tons of rotor with 65 tons of ingot was made in real size and was cut to pieces to take test samples, and the various mechanical tests such as impact, tensile, creep, and fatigue were carried out. The strengths are compared with those of 1% Cr-Mo-V rotor of same size. Microstructures of the samples are examined and reviewed. The results can be summarized as follows. 1) Fracture appearance transition temperatures are 80.deg. C at the center part and 60.deg. C near surface of 12% Cr rotor, and 8.deg. C near surface of 1% Cr-Mo-V rotor. 2) Comparative rapid softening occurs at higher temperatures above 600.deg. C for 12% Cr steel and 550.deg. C for 1% Cr-Mo-V steel in tension tests. 3) Fatigue crack propagation rate of 12% Cr steel is almost same as that of 1% Cr-Mo-V steel at the same corresponding surface part of the rotors. The crack growth rate of center part of 12% Cr rotor is faster than near surface part of the rotor, and the crack growth rate at the load condition of R=0.04 is slower than that of the load condition of R=0.5 for both 12% Cr steel and 1% Cr-Mo-V steel. 4) Crack growth rate of radial direction near surface of 12% Cr rotor is faster than that of transverse direction at the same part because of the difference in residual stresses. 5) Both creep and fatigue strengths of 12% Cr steel are superior to those of 1% Cr-Mo-V steel and the difference is thought the effect of climb and glide controlled creep by solid solution of alloying elements and dispersion of carbides.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.625-625
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• 1989

To check technical improvement in the soundness and strength of 12% Cr steel rotor, a 25 tons of rotor with 65 tons of ingot was made in real size and was cut to pieces to take test samples, and the various mechanical tests such as impact, tensile, creep, and fatigue were carried out. The strengths are compared with those of 1% Cr-Mo-V rotor of same size. Microstructures of the samples are examined and reviewed. The results can be summarized as follows. 1) Fracture appearance transition temperatures are 80.deg. C at the center part and 60.deg. C near surface of 12% Cr rotor, and 8.deg. C near surface of 1% Cr-Mo-V rotor. 2) Comparative rapid softening occurs at higher temperatures above 600.deg. C for 12% Cr steel and 550.deg. C for 1% Cr-Mo-V steel in tension tests. 3) Fatigue crack propagation rate of 12% Cr steel is almost same as that of 1% Cr-Mo-V steel at the same corresponding surface part of the rotors. The crack growth rate of center part of 12% Cr rotor is faster than near surface part of the rotor, and the crack growth rate at the load condition of R=0.04 is slower than that of the load condition of R=0.5 for both 12% Cr steel and 1% Cr-Mo-V steel. 4) Crack growth rate of radial direction near surface of 12% Cr rotor is faster than that of transverse direction at the same part because of the difference in residual stresses. 5) Both creep and fatigue strengths of 12% Cr steel are superior to those of 1% Cr-Mo-V steel and the difference is thought the effect of climb and glide controlled creep by solid solution of alloying elements and dispersion of carbides.

• Journal of the Korean Ceramic Society
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• v.47 no.6
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• pp.638-642
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• 2010

The spinel material $Li_4Ti_5O_{12}$ has attracted considerable attention as an anode electrode material for many battery applications owing to its light weight and high energy density. However, the real capacity of $Li_4Ti_5O_{12}$ powder as determined by the solid-state method is lower than the ideal capacity. In this study, we investigated the effect of the dopants in M-doped spinel $Ba_xLi_{4-2x}Ti_5O_{12}$(x=0.005, 0.05, 0.1) powders prepared by the solid-state reaction method and used as the anode material in lithiumion batteries. The results confirmed the effect of the Ba and Sr dopants on the powder properties of the spinel $Li_4Ti_5O_{12}$, which exhibited a pure spinel structure without any secondary phase in its XRD pattern. Moreover, the electrochemical properties of the spinel M-LTO materials were investigated using a half cell. The electrochemical data show that cells with anodes made of undoped $Li_4Ti_5O_{12}$ and Ba- and Sr-doped $Li_4Ti_5O_{12}$ have discharge capacities of 97, 130, and 112 mAh/g, respectively, at the first cycle. Moreover, the Ba- and Sr-doped spinel $Li_4Ti_5O_{12}$ demonstrated good properties in the mid-voltage range at 1.55 V, showing stable cyclic voltammogram properties which surpassed those of the same material without Ba or Sr at 1 C after 100 cycles.