• Carbon letters
• /
• v.8 no.1
• /
• pp.12-16
• /
• 2007

Molecular sieving carbon (MSC) for separating $O_2-N_2$ and $CO_2-CH_4$ has been prepared through chemical vapor deposition (CVD) of methane and benzene on activated carbon spheres (ACS) derived from polystyrene sulfonate beads. The validity of the material for assessment of molecular sieving behavior for $O_2-N_2$ and $CO_2-CH_4$ pair of gases was assessed by the kinetic adsorption of the corresponding gases at $25^{\circ}C$. It was observed that methane cracking on ACS lead to deposition of carbon mostly in whole length of pores rather than in pore entrance, resulting in a reduction in adsorption capacity. MSC showing good selectivity for $CO_2-CH_4$ and $O_2-N_2$ separation was obtained through benzene cracking on ACS with benzene entrantment of $0.40{\times}10^{-4}\;g/ml$ at cracking temperature of $725^{\circ}C$ for a period of 90 minutes resulting in a selectivity of 3.31:1.00 for $O_2-N_2$ and 8.00:1.00 for $CO_2-CH_4$ pair of gases respectively.

• Preventive Nutrition and Food Science
• /
• v.17 no.2
• /
• pp.152-157
• /
• 2012

This study was performed to increase the availability of Sedum sarmentosum (Dolnamul) and to improve the nutraceutical value of rice cakes (sulgitteok). The contents of crude protein, mineral, dietary fiber, water holding capacity, and hardness significantly and directly increased with lyophilized sedum powder (SP). Pore ratio and expansion rate decreased in samples containing more than 10% SP compared to the control. In a sensory evaluation, a positive correlation was detected between overall acceptability and taste ($R^2$=0.99, p<0.01), and color ($R^2$=0.72, p<0.05). Total polyphenol contents of the SP-treated groups were significantly elevated, accompanied by an increase in radical scavenging ability estimated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Replacing 10% of the rice powder with SP efficiently improved the antioxidant and nutritional values of sulgitteok as well as its the sensory quality.

• Carbon letters
• /
• v.13 no.2
• /
• pp.109-114
• /
• 2012

A nuclear, biological, chemical (NBC) canister was indigenously developed using active carbon impregnated with ammoniacal salts of copper (II), chromium (VI) and silver (I), and high efficiency particulate aerosol filter media. The NBC canister was evaluated against carbon tetra chloride ($CCl_4$) vapours, which were used as a simulant for persistent chemical warfare agents under dynamic conditions for testing breakthrough times of canisters of gas masks in the National Approval Test of Respirators. The effects of $CCl_4$ concentration, test flow rate, temperature, and relative humidity (RH) on the breakthrough time of the NBC canister against $CCl_4$ vapour were also studied. The impregnated carbon that filled the NBC canister was characterized for surface area and pore volume by $N_2$ adsorption-desorption isotherm at liquid nitrogen temperature. The study clearly indicated that the NBC canister provides adequate protection against $CCl_4$ vapours. The breakthrough time decreased with the increase of the $CCl_4$ concentration and flow rate. The variation in temperature and RH did not significantly affect the breakthrough behaviour of the NBC canister at high vapour concentration of $CCl_4$, whereas the breakthrough time of the NBC canister was reduced by an increase of RH at low $CCl_4$ vapour concentration.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2015.07a
• /
• pp.216-217
• /
• 2015

This study consist of research on the strength development properties of alkali activated slag(AAS) by differential combination of activators, initial protecting and curing conditions. 3 type of binders cured in the atmosphere, underwater and sealed were estimated compressive strength of 3, 7 and 28 days. Test results showed that strength development properties of binders varied with initial protecting and curing conditions because of ionized anions in pore water.

• Development and Reproduction
• /
• v.16 no.1
• /
• pp.69-75
• /
• 2012

Hatching occurred in the time dependent manners and strictly controlled. Although, the hatching processes are under the control of muti-embryotrophic factors and the expressed G proteins of cell generate integrated activation, the knowledge which GPCRs are expressed during hatching stage embryos are very limited. In the present study, which G proteins are involved was examined during blastocyst development to the hatching stage. The early-, expanded-, and lobe-stage blastocysts were treated with various $G_{\alpha}$ activators and H series inhibitors, and examined developmental patterns. Pertusis toxin (PTX) improved the hatching rate of the early-stage blastocyst and lobe-formed embryos. Cholera toxin (CTX) suppressed the hatching of the early-stage blastocyst and expanded embryos. The effects of toxins on hatching and embryo development were changed by the H7 and H8. These results mean that PTX mediated GPCRs activation is signaling generator in the nick or pore formation in the ZP. In addition, PTX mediated GPCR activation induces the locomotion of trophectoderm for the escaping. CTX mediate GPCRs activation is the cause of suppression of hatching processes. Based on these data, it is suggested that various GPCRs are expressed in the periimplantation stage embryos and the integration of the multiple signals decoding of various signals in a spatial and temporal manner regulate the hatching process.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.19 no.2
• /
• pp.81-87
• /
• 2009

Final purpose of this study was designed to develop the quality control(QC) sample for proficiency analytical testing of asbestos. This study consisted of two parts; first, development of manufacturing apparatus and sample preparing procedure for asbestos quality control(QC) sample: second, validation of the QC samples made by our developed method as asbestos proficiency analytical testing sample. The main results of the first part research are as followed We developed the apparatus for manufacturing the asbestos QC sample, consisted of filter hold, filter holder manifolder, vacuum system, and vacuum pump. The most proper filter of making the QC samples was a cellulose ester membrane filter with 25 mm diameter, pore size 0.8 um. And we presented the optimal procedure for preparing the asbestos QC sample by using the developed apparatus. We will verify the manufactured asbestos QC samples by this method, and present the validation results to confirm the reliability as a asbestos QC sample in next paper.

• Geosystem Engineering
• /
• v.21 no.6
• /
• pp.344-351
• /
• 2018

It is reported that the flooding rate in low permeability sandstones is low and the oil recovery is hard to increase after water breakthrough. Understanding characteristics of waterflood is hence important for the recovery improvement. In this work, flooding tests on low permeability sandstones were conducted. The corresponding flooding characteristics were investigated by means of CT scanning and Nuclear Magnetic Resonance. Effects of irreducible water and different rates were also discussed in detail. Experimental results reveal a piston-like displacement at a low rate in low permeability samples. The saturation profile is steep and almost vertical to the forward direction. The results at a low rate confirm that once water broke through, increasing the flooding rate or flooding time can hardly reduce the remaining oil inside the sample. It is probably due to the high pore-throat ratio proven by rate-controlled mercury. Results also confirm that the presence of initial water enhanced sweep efficiency substantially. On one hand, because water had previously occupied the small pores, the subsequent oil can only invade relatively large pores and became more movable. On the other hand, stable collars can not form due to the steep front, which may suppress the snap-off.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.110-110
• /
• 2017

Stomata are the main gateways for water and air transport between leaves and the environment. Inward-rectifying potassium channels regulate photo-induced stomatal opening. Rice contains three inward rectifying shaker-like potassium channel proteins, OsKAT1, OsKAT2 and OsKAT3. Among these, only OsKAT2 is specifically expressed in guard cells. Here, we investigated the functions of OsKAT2 in stomatal regulation using three dominant negative mutant proteins, OsKAT2(T235R), OsKAT2(T285A) and OsKAT2(T285D), which are altered in amino acids in the channel pore and at a phosphorylation site. Yeast complementation and patch clamp assays showed that all three mutant proteins lost channel activity. However, among plants overexpressing these mutant proteins, only plants overexpressing OsKAT2(T235R) showed significantly less water loss than the control. Moreover, overexpression of this mutant protein led to delayed photo-induced stomatal opening and increased drought tolerance. Our results indicate that OsKAT2 is an inward-rectifying shaker-like potassium channel that mainly functions in stomatal opening. Interestingly, overexpression of OsKAT2(T235R) did not cause serious defects in growth or yield in rice, suggesting that OsKAT2 is a potential target for engineering plants with improved drought tolerance without yield penalty.

• The Journal of Engineering Geology
• /
• v.28 no.2
• /
• pp.247-258
• /
• 2018

In the demonstration-scale offshore $CO_2$ storage project, the monitoring team studies geophysical and geochemical monitoring of $CO_2$ injections in the Yeongil Bay, in which a $CO_2$ test injection (about 100t) was performed in January, 2017 and further injections in larger scales are planned for 2018 and 2019. In this study, the development status of the Korea-type Hydro-Geophone OBS (Ocean Bottom Sensor) and the geochemical baseline survey (focused on some anions of sediment pore water) are suggested as the preliminary results of the pre-injection test.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.1 no.2
• /
• pp.33-40
• /
• 2000

The present invention relates to a absorption rotor for removed VOC(volatile organic compound) and humidity in semiconductor clean room system. A absorption rotor medium is made by NaX zeolite and TS-1 zeolite formed on a honeycomb matrix of ceramic papers. The crystallization of NaX zeolite was hydrothermal reaction, and NaX zeolite crystals of a uniform particle size of 5$\mu$m were synthesized that NaX zeolite seed crystals (2~3$\mu$m) added in a batch composition at levels of 3~15 wt$\%$. The seeding resulted in an increase in the fraction of large crystals compared with unseeded batches and successfully led to a uniform NaX zeolite crystal. The microporous zeolite-type titanosilicate(TS-1) was synthesized by different of the reactant solution pH. The pH range of reactant solution has been changed from 10.0 to 11.5 TS-1 zeolite (ETS-10), having a large pore(8~10 $\AA$), was synthesized at 10.4 of pH, since TS-1 zeolite (ETS-4), having a small pore(3~5$\AA$), was synthesized at 11.5 of pH.