• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.708-712
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• 2012

Ionic liquids (ILs) existing as liquid state at room temperature are composed of a immense heterocyclic cation and inorganic anion which is smaller than cation's size. Thus, the species of cation and anion as well as the length of alkyl group on the cation have influence on their physical properties. Their outstanding properties such as non-volatility, thermal stability and wide range of electrochemical stability make these materials excellent candidates for green solvent which can substitute the conventional organic solvents. In this study, ILs based on imidazolium cation have been synthesized such as 1-butyl-3-methylimidazolium bromide ([BMIM][Br]), 1-butyl-3-methylimidazolium chloride ([BMIM] [Cl]), 1-butyl-3-methylimidazolium iodide ([BMIM][I]), and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][$BF_4$]). The density, viscosity, refractive index, heat capacity and ionic conductivity of [BMIM][Br], [BMIM][I], and [BMIM] [$BF_4$] were measured over range of temperature of 293.2 to 323.2 K. The density and refractive index values of [BMIM][I] were the highest among three ILs and the viscosity values of [BMIM][Br] were the highest among three ILs. The heat capacities [BMIM][$BF_4$] were higher than those of [BMIM][Br]. The ionic conductivities of [BMIM][$BF_4$] were higher than those of [BMIM][I].

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.2
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• pp.32-45
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• 2000

This paper presents the analytic derivation of the SINR, when a linear array antenna is accommodated into the cellular CDMA basestation receiver, in relation to the two major performance effecting factors in beamforming(BF) applications, i. e., the direction selectivity, which refers to the narrowness of the mainbeam width, and the direction-of-arrival(DOA) estimation accuracy. The analytically derived results are compared with the operation simulation of the receiver realized with the several BF algorithms and their agreements are confirmed, consequently verifying the correctness of the analysis and the operation simulation. In order to investigate separately the effects of the errors occurring in the direction estimation and in the interference suppression, which are the two major functional components of general BF algorithms, both the algorithms of steering BF and the minimum- variance- distortionless-response(MVDR) BF are applied to the analysis. A signal model to reflect the spatially scattering phenomenon of the RF waves entering into the .:nay antenna, which directly affects on the accuracy of the BF algorithm's direction estimation, is also suggested in this paper and applied to the analysis and the operation simulation. It is confirmed from the results that the enhancement of the direction selectivity of the away antenna is not desirable in view of both the implementation economy and the BF algorithm's robustness to the erroneous factors. Such a trade-off characteristics is significant in the sense that it can be capitalized to obtain an economic means of BF implementation that does not severely deteriorate its performance while ensuring the robustness to the erroneous effects, consequently manifesting the significance of the analysis results of this paper that can be used as a design reference in developing BF algorithms to the cellular CDMA system.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.2
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• pp.153-162
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• 2021

The effects of activated carbon originated Ballasted Flocculant (BF) on the settleability of activated sludge and the recovery of BF by Hydro-cyclone (HC) were analyzed experimentally. Two kinds of BF (M-I: 125-250 ㎛, M-II: 250-425 ㎛ in dia.) and three kinds of activated sludges with different SS concentration (2,300-7,100 mg/L) were applied for this study. With the dosage variation of BF from 0.14 to 1.3 g-BF/g-SS, we could obtain 24-31% improvement in SV30 (Sludge Volume after 30min sedimentation) for the lowest SS concentration sludge (2,300 mg/L). Whereas the SV30 improvement was much higher as 44-48% for the highest SS concentration sludge (7,100 mg/L). The settling characteristics of the sludge with BF followed Vesilind model the best among three models (Vesilind, Takacs and Cho model). HC could effectively separate BF with the separation efficiency of 70-90% and over 95% separation efficiency could be obtained when the HC was applied twice.

• Transactions on Electrical and Electronic Materials
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• v.11 no.3
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• pp.120-125
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• 2010

For the fabrication of PMOS and integrated semiconductor devices, B, $BF_2$ and dual elements with B and $BF_2$ can be implanted in silicon. 15 keV B ions were implanted in silicon at $7^{\circ}$ wafer tilt and a dose of $3.0{\times}10^{16}\;cm^{-2}$. 67 keV $BF_2$ ions were implanted in silicon at $7^{\circ}$ wafer tilt and a dose of $3.0{\times}10^{15}\;cm^{-2}$. For dual implantations, 67 keV $BF_2$ and 15keV B were carried out with two implantations with dose of $1.5{\times}10^{15}\;cm^{-2}$ instead of $3.0{\times}10^{15}\;cm^{-2}$, respectively. For the electrical activation, the implanted samples were annealed with rapid thermal annealing at $1,050^{\circ}C$ for 30 seconds. The implanted profiles were characterized by using secondary ion mass spectrometry in order to measure profiles. The implanted and annealed results show that concentration profiles for the ${BF_2}^+$ implant are shallower than those for a single $B^+$ and dual ($B^+$ and ${BF_2}^+$) implants in silicon. This effect was caused by the presence of fluorine which traps interstitial silicon and ${BF_2}^+$ implants have lower diffusion effect than a single and dual implantation cases. For the fabricated diodes, current-voltage (I-V) and capacitance-voltage (C-V) were also measured with HP curve tracer and C-V plotter. Electrical measurements showed that the dual implant had the best result in comparison with the other two cases for the turn on voltage characteristics.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.12
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• pp.53-58
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• 1991

Hot-carrier induced degradation has been studied for the BF$_2$ ion-implanted surface-channel LDD(P$^{+}$ polysilicon gate) PMOSFET in comparison to the buried-channel structure(N$^{+}$ polysilicon gate) PMOSFET. The conditions for maximum degradation better correlated to I$_{g}$ than I$_{sub}$ for both PMOSFET's. Due to the use of LDD structure on SC-PMOSFET, the substrate current for SC-PMOSFET was shown to be smaller than that of BC-PMOSFET. The gate current was smaller as well, due to the gate material work-function difference between p$^{+}$ and n$^{+}$ polysilicon gates. From the results, it was shown that the surface-channel LDD PMOSFET is more resistant to short channel effect than the buried-channel PMOSFET.

• Journal of Haehwa Medicine
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• v.10 no.2
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• pp.11-19
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• 2002

To evaluate the antitumor activity and antimetastatic effects of Bruceae FructusCBF), studies were done experimentally. The results were obtained as follows : 1. In cytotoxicity against A549, SK-MEL-2, MCF-7 and XF498 cell concentration inhibiting cell growth up to below 50% of control was recognized at $25{\mu}g/m{\ell}$ of BF. Also BF inhibited cell growth up to below 50% of control against HCT15 cell at $12.5{\mu}g/m{\ell}$, so it showed stronger cytotoxicity against HCT15 cell than another cancer cell. 2. In Inhibitory effect on activity of DNA topoisomerase- I, the $IC_{50}$ was shown $10-50{\mu}g/m{\ell}$ of BF. 3. The T/C% was 143.4 in BF treated group in S-180 bearing ICR mice. 4. The concentration inhibiting adhesion of A549 and SK-OV-3 to complex extracellular matrix up to below 30% of control was recognized at $1{\mu}g/m{\ell}$ of BF. 5. In pumonary colonization assay, a number of colonies in the lungs were decreased significantly in BF treated group as compared with control group. These results suggested that BF extracts might be usefully applied for prevention and treatment of cancer.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.555-563
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• 2018

Barley has nutritional benefits due to its high dietary fiber content; therefore, the intake of whole barley grains is recommended. However, barley is often consumed in the fermented form because of the improved texture and digestibility. The present study was designed to elucidate the intracellular signaling pathway for macrophage activation by the polysaccharide BF-CP from fermented barley. BF-CP is a neutral polysaccharide, composed of neutral sugars, including glucose (70.7%), xylose (11.4%), and arabinose (9.0%). BF-CP exhibited macrophage-stimulatory activity by inducing the production of interleukin (IL)-6, tumor necrosis factor $(TNF)-{\alpha}$, and nitric oxide in RAW 264.7 macrophages. Further, BF-CP treatment strongly increased the IL-6 and $TNF-{\alpha}$ gene expression in a concentration-dependent manner. Signal transduction experiments using immunoblotting showed that BF-CP phosphorylated mitogen-activated protein kinases (MAPKs), such as c-Jun N-terminal kinase, extracellular signal-regulated kinase, and p38, and nuclear factor $(NF)-{\kappa}B$, in RAW 264.7 cells in a concentration-dependent manner. These results suggest that BF-CP activates the macrophages via MAPK and $NF-{\kappa}B$ pathways, and also induces an increase in the production of cytokines.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.439-445
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• 2018

Experimental measurements of the response of $BF_3$ detector to a 3 Ci Am-Be neutron source for three different reflecting materials, i.e., aluminum, wood, and Perspex of varying thicknesses have been carried out. The varying contribution of wall effect to the response due to change in active volume of the detector has also been determined experimentally. Then, a Monte Carlo code has been developed for the calculation of the neutron response function of the $BF_3$ detector using source biasing and importance sampling. This code simulates the $BF_3$ detector response exposed to the neutron field in a three-dimensional source, detector, and reflecting medium configurations. The results of simulation have been compared with the corresponding experimental measurements and are found to be in good agreement. The experimental neutron albedo measurements for various values of Perspex thickness show saturating behavior, and results agree very well with the data obtained by Monte Carlo simulation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.180-187
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• 2015

This study was conducted to determine the effects of feeding by-product feed (BF)-based silage on the performance, blood metabolite parameters, and carcass characteristics of Hanwoo steers. The BF-based silage was composed of 50% spent mushroom substrate, 21% recycled poultry bedding, 15% cut ryegrass straw, 10.8% rice bran, 2% molasses, 0.6% bentonite, and 0.6% microbial additive (on a wet basis), and ensiled for over 5 d. Fifteen steers were allocated to three diets during the growing and fattening periods (3.1 and 9.8 months, respectively): a control diet (concentrate mix and free access to rice straw), a 50% BF-based silage diet (control diet+50% of maximum BF-based silage intake), and a 100% BF-based silage diet (the same amount of concentrate mix and ad libitum BF-based silage). The BF-based silage was fed during the growing and fattening periods, and was replaced with larger particles of rice straw during the finishing period. After 19.6 months of the whole period all the steers were slaughtered. Compared with feeding rice straw, feeding BF-based silage tended (p = 0.10) to increase the average daily gain (27%) and feed efficiency (18%) of the growing steers, caused by increased voluntary feed intake. Feeding BF-based silage had little effect on serum constituents, electrolytes, enzymes, or the blood cell profiles of fattening steers, except for low serum Ca and high blood urea concentrations (p<0.05). Feeding BF-based silage did not affect cold carcass weight, yield traits such as back fat thickness, longissimus muscle area, yield index or yield grade, or quality traits such as meat color, fat color, texture, maturity, marbling score, or quality grade. However, it improved good quality grade (1+ and 1++) appearance rates (60% for the control group vs 100% for the BF-based silage-fed groups). In conclusion, cheap BF-based silage could be successfully used as a good quality roughage source for beef cattle.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1222-1228
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• 2007

The aim of this experiment was to compare the characterization of fatty acid digestion of Beijing Fatty (BF) and Arbor Acres (AA) chickens. One-day-old male AA and BF chickens were raised in the same house, and fed with the same diet. We first evaluated utilization of dietary fatty acids in chickens by the total collection procedure, and chickens were then killed to compare the abundance of intestinal mRNA expression of liver-fatty acid binding protein (L-FABP) and intestinal-fatty acid binding protein (I-FABP) by Real-time PCR, and also the pH of intestinal mucosa at 3 and 6 weeks of age. Another group of chickens were sampled at 6 weeks of age to compare the total bile acid concentration in serum, and lipase activity in contents of the small intestine. Results showed that compared to AA chickens, BF chickens had higher lipase activity in the content of the small intestine (p<0.05), greater total bile acid content in portal vein blood (p<0.05) at 6 weeks of age, lower intestinal mucosal pH at both 3 weeks (p<0.05) and 6 weeks (p<0.05) of age, and higher abundance of liver-fatty acid binding protein (L-FABP) mRNA expression in intestine tissues at 6 weeks of age (p<0.05), and higher digestibility of fatty acids at both 3 and 6 weeks (p<0.05) of age. There was no difference in I-FABP mRNA expression between AA and BF chickens at either age. Thus, BF chickens had greater fatty acids utilization than AA chickens that was associated with L-FABP, lipase activity, bile acid content and intestinal mucosal pH.