• Journal of Korean Society of Water and Wastewater
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• v.14 no.4
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• pp.350-355
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• 2000

Powdered activated carbon(PAC) is widely used to control 2-MIB와 geosmin causing earthy-musty odor in water supplies. It was known that chlorine is one of the chemicals often come into contact with activated carbon. But activated carbon react with chlorine and surface oxide accumulate on carbon surface. As result, adsorption capacity of activated carbon is reduced. To investigate the effect of chlorine on the PAC's ability to adsorb 2-MIB and Geosmin, a series of experiments was carried out to show (1) the effect of aqueous chlorine doses on the ability of PAC to adsorb 2-MIB and Geosmin from Lake Heodong water. (2) the effect of delaying the chlorine addition after PAC had been added (to simulate the effect of using an alternative point of chlorine addition). As a result of experiment, as chlorine dose increased correspondingly decreased the capacity of activated carbon to adsorb 2-MIB and geosmin. Even though previously adsorbed 2-MIB and geosmin released, as result of the application of delaying the chlorine adding was more beneficial than simultaneous adding chlorine with PAC.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.913-916
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• 2009

Femtosecond vibrational spectroscopy was used to probe the dynamics of CO rebinding to hemoglobin (Hb), denatured by 4.0 M GdnHCl in $D_2O# at 283 K, after photolysis of HbCO. The stretching mode of $^{13}CO$ bound to the denatured $Hb^{13}CO$ showed a single band centered at 1922 $cm^{-1}$, indistinguishable from that of denatured $Mb^{13}CO$. Geminate rebinding of CO to the denatured Hb was accelerated more than 1000 times, suggesting that the native structure of the Hb is required to suppress efficient geminate rebinding of CO, as is the case in Mb. The geminate yield and rate for CO rebinding are almost the same in both the denatured Hb and Mb. Similarity in the equilibrium spectrum and rebinding dynamics of CO indicates that the state of the denatured Hb is very similar to that of the denatured Mb. In the denatured Hb, quaternary contact of the protein is likely severed, with the denatured protein existing as an independent subunit much like Mb.

• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1420-1427
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• 2016

Geosmin and 2-methylisoborneol (2-MIB) are two of the most common taint compounds that adversely affect the quality of aquacultural animals. In the present study, 94% of geosmin and 97% of 2-MIB in suspended growth reactors producing bioflocs (SGRs) with aquaculture waste were removed after inoculation with Bacillus subtilis, significantly higher than that of control SGRs (70% of geosmin and 86.4% of 2-MIB). The lowest concentrations of geosmin and 2-MIB achieved in the effluent of the SGRs were 2.43 ± 0.42 ng/l and 2.23 ± 0.15 ng/l, respectively. The crude protein content of the bioflocs produced in the SGRs was 35 ± 4%. The NH₄⁺-N and NO₂^--N concentrations in the effluent of the reactors were 1.13 ± 0.21 mg/l and 0.42 ± 0.04 mg/l, respectively. These results suggest that inoculated with Bacillus subtilis, SGRs have a better performance to reuse the nitrogen in fish waste and to remove geosmin and 2-MIB from the culture water efficiently.

• Applied Chemistry for Engineering
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• v.32 no.3
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• pp.348-356
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• 2021

The lignocellulose-based dried watermelon rind (WR) was modified with sulfuric acid, namely SWR for enhancement of methylene blue (MB) adsorption from the aqueous solution. According to FT-IR analysis, after the modification of WR with sulfuric acid, the functional groups of R-SO₃H, COOH and -OH groups was formated or enhanced on the surface of the WR. Moreover, the point of zero charge (pHpzc) was changed from 6.3 to 4.1 after modification, which widened the range for adsorbing of cationic dye MB. The adsorption process of MB onto the SWR was suitable for pseudo-2nd-order and Langmuir model and the maximum adsorption capacity of Langmuir was found to be 334.45 mg/g at pH 7. In adition, the adsorption process occurs through the electrostatic interaction, hydrogen bridge formation, electron donor-acceptor relationship, and 𝜋-𝜋 electron dispersing force between functional groups on the carbon surface with MB molecules. Depending on functional groups available on the SWR surface, the MB adsorption mechanism can occur in combination with various interactions.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.274-274
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• 2004

The purpose of this study is to evaluate the efficacy of in vitro differentiated human embryonic stem (MB03) cells expressing Nurr1 in relief of symptomatic motor behavior of Parkinson's disease (PD) animal models. MB03 cell was genetically modified to express Nurr1 protein (Nr#24/MB03) and was induced to differentiate according to 2- /4+ protocol using retinoic acid and ascorbic acid. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.141.1-141.1
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• 2003

The inhibitory effect of 13(E)-Labd-13-ene-8$\alpha$ 15-diol(1), isolated from the ethanol extract of Brachyglottis monroi, on the proliferation of human breast cancer MDA-MB231 cells was examined. Compound (1) at concentration as high as 16$\mu$/$m\ell$ has inhibited the proliferation of MDA-MB231 and this cytotoxic effect was increased in a time and dose-dependent manners. (omitted)

• Journal of Sensor Science and Technology
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• v.10 no.4
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• pp.214-221
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• 2001

The use of an asymmetric Mach-Zehnder interferometric amplitude modulator to measure a relatively low frequency electric field strength is described. The sensitivity of an electric field sensor using a $Ti:LiMbO_3$ optical modulator is strongly affected by the shape of a electrode(probe antenna). To measure the low frequency electric field, a probe antenna of wide effective area is more useful than the usual dipole antenna. As a proof of this, the optical modulator was fabricated with a plate-type probe antenna and the usefulness of this antenna tested for measuring low frequency electric field strength. Measurements were performed in the range 0.1 V/cm to 60 V/cm at 60Hz through 100 kHz. Using a probe antenna of $10\;mm{\times}10\;mm$, the output voltage of $10^{-2}\;mV$ was measured with respect to the electric field strength of 0.1 V/cm at 60 Hz. By increasing the effective area of the probe antenna, better sensitivity is obtainable over the measured range.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.12A
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• pp.1174-1182
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• 2005

This paper, we propose a new channel Estimation method for MB-OFDM(Multi-Band OFDM) system that is suggested as one of standards in IEEE 802.15 TG3a for high data rate(110Mbps${\~}$480Mbps) WPAN system. The proposed method uses correlation characteristic of the PS(Packet Synchronization) sequence for timing synchronization. It can reduce the influence of noise compared with the conventional algorithm which based on LS(Least square) algorithm is redundancy without using the CE(Channel Estimation) Sequence for channel Estimation. We simulate both conventional method and proposed method for performance analysis in S-V channel environment which proposed by IEEE 802.15.3a. Simulation results show the proposed algorithm outperforms conventional algorithm about 1${\~}$1.5dB of Eb/NO.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.125-133
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• 1998

This study was designed to identify the efficiency of serum troponin-T(s-TnT) level as a diagnostic indicator for the perioperative myocardial damage with open heart surgery(OHS) and to compare with the conventional myocardial enzyme tests such as isoenzyme fraction of creatine kinase(% CK-MB) and isoenzyme ratio of lactate dehydrogenase(LDH1/LDH2 ratio). The study was performed on 30 adult patients who underwent OHS from Jan. 1996 to June 1996 at Inje University Pusan Paik Hospital, and they were divided into two groups accor- ding to aortic clamping time(ACT) duration : group I(ACT＜60 minutes, n=15); group II (ACT＞60 minutes, n=15). S-TnT, % CK-MB, and LDH1/LDH2 ratio were measured in serial blood samples from all subjected patients. The results were obtained as follows. 1. In both groups, s-TnT concentrations increased gradually during OHS and elevated significantly at CPB-10(p＜0.001). The peak level was noticed at POD 1 in group I(1.10 $\pm$0.19 ng/ml), whereas, at CPB-off in group II(1.88$\pm$0.42 ng/ml). The elevated levels remained until POD 7 in both groups. 2. %CK-MB was risen significantly with the initiation of operations(p＜0.001) and the peak levels were noticed at CPB-off in both groups(7.14$\pm$0.86% in group I, 10.69$\pm$1.27% in group II). Thereafter, these levels returned to normal values at POD 3. 3. There were no significant changes in the values of LDH1/LDH2 ratio during and after OHS compared with the control levels(p＞0.05). 4. The serial changes of s-TnT were relatively well correlated with those of changes of % CK-MB(r=0.64, p＜0.05). 5. The serial s-TnT levels were significantly higher in group II than group I from B-ACR to POD 1(p＜0.05), suggesting that duration of aortic clamping time was a major factor concerned with perioperative myocardial injury. In conclusion, measurement of s-TnT is a very useful indicator in assessing the myocardial cell damage and therefore it is expected that serial checking and evaluation of the s-TnT is very available for identification of the perioperative myocardial damage and for postoperative cares in patients with OHS.

• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.758-764
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• 2014

Femtosecond vibrational spectroscopy was used to measure the vibrational population relaxation time ($T_1$) of different anions bound to ferric myoglobin ($Mb^{III}$) and hemoglobin ($Hb_{III}$) in $D_2O$ at 293 K. The $T_1$ values of the anti-symmetric stretching (${\nu}_1$) mode of NCS in the $NCS^-$ bound to $Mb^{III}$ ($Mb^{III}$NCS) and $Hb_{III}$ ($Hb_{III}$NCS) in $D_2O$ are $7.2{\pm}0.2$ and $6.6{\pm}0.2$ ps, respectively, which are smaller than that of free NCS. in $D_2O$ (18.3 ps). The $T_1$ values of the ${\nu}_1$ mode of NCO in the $NCO^-$ bound to $Mb^{III}$ ($Mb^{III}$NCO) and $Hb_{III}$ ($Hb_{III}$NCO) in $D_2O$ are $2.4{\pm}0.2$ and $2.6{\pm}0.2$ ps, respectively, which are larger than that of free $NCO^-$ in $D_2O$ ($1.9{\pm}0.2$ ps). The smaller $T_1$ values of the ${\nu}_1$ mode of the heme-bound NCS suggest that intramolecular vibrational relaxation (VR) is the dominant relaxation pathway for the excess vibrational energy. On the other hand, the longer $T_1$ values of the ${\nu}_1$ mode of the heme-bound NCO suggest that intermolecular VR is the dominant relaxation pathway for the excess vibrational energy in the ${\nu}_1$ mode of $NCO^-$ in $D_2O$, and that intramolecular VR becomes more important in the vibrational energy dissipation of the ${\nu}_1$ mode of NCO in $Mb^{III}$NCO and $Hb_{III}$NCO.