• Bulletin of the Korean Chemical Society
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• v.16 no.12
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• pp.1212-1218
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• 1995

An efficient synthesis of 6,8-dioxa-1,4-diazacyclopenta[b]phenanthren-5-one (Pyrazinopsoralen) (4) has been carried out by the Suzuki coupling reaction as a key step starting from 5-bromo-6-methoxybenzofuran (6) and methyl 2-iodo-3-pyrazinecarboxylate (8).

• Progress in Superconductivity and Cryogenics
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• v.25 no.4
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• pp.14-18
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• 2023

We have investigated the behavior induced by Ga substitution in B-1212 system and observed an anomalous superconductor-like resistivity drop with an onset near 260 K and an offset at 248 K in the nominal (B_0.65Ga_0.35)(Ba_1.25Sr_0.75)(Er_0.5Ca_0.5)Cu₂O_z compound. However, this property degraded with repeated cycling. Systematic studies of the superconducting properties of the (B_1-xGa_x)(Ba_1.25Sr_0.75)(Er_0.5Ca_0.5)Cu₂O_z compounds are reported and discussed in the context of the anomalous resistivity transition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.12
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• pp.1212-1218
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• 2014

This paper proposes a planar bow-tie UWB antenna by modifying the ground patch of a reference bowtie-monopole antenna satisfying low band of UWB. The proposed antenna was implemented with five-angled ground patch to be operated in whole UWB band, while the reference antenna had a ground patch of half circle type. The measured return loss satisfies less than -10 dB in 3.1~10.6 GHz, except 4.9~5.8 GHz rejection band. The measured radiation pattern is almost the same with that of the monopole antenna. The radiation gain reduction is about 8 dB at rejection band.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.8
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• pp.1212-1216
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• 2015

In this paper, we compared the performance of the Right Handed Nonlinear Transmission Line (RH-NLTL) and Left Handed Nonlinear Transmission Line (LH-NLTL) as a harmonic generator. For a performance comparison, we fabricated both a RH-NLTL and a LH-NLTL harmonic generator whose operational bandwidth is from 0.5 GHz to 1.5 GHz. Under the each condition for the RH-NLTL and the LH-NLTL to maximize second harmonic, the output power of the second harmonic was 9.33 dB lower than the input power for the RH-NLTL and 12.67 dB lower than the input power for the LH-NLTL. Under the each condition for the RH-NLTL and the LH-NLTL to maximize third harmonic, the output power of the third harmonic was 13.33 dB lower than the input power for the RH-NLTL and 14.83dB lower than the input power for the LH-NLTL. Also, we have observed that, generatlly, a RH-NLTL is useful in generating various multiple harmonics and a LH-NLTL is useful in generating a specific order of harmonic by adjusting a proper DC vias, input frequency and input power. These tendencies could be a good guideline to use NLTLs as a frequency multiplier.

• Journal of Veterinary Clinics
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• v.26 no.2
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• pp.117-122
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• 2009

The aim of this study is to investigate the effects of surfactin in combination with Bacillus subtilis BC1212 isolated from Korean soybean paste, on feed utilization and growth performance during 4 weeks in weaning piglets. Eighteen weaning piglets(Landrace$\times$Yorkshire$\times$Duroc; weighing $7.68{\pm}0.97\;kg$) were divided into control(n=9) and experimental groups(n=9). The treatments included a control group consisting of the basal diet with no additives(control) and an experimental group consisting of the basal diet supplemented with 1 g of surfactin C and $1.0{\times}10^9CFU$ of Bacillus subtilis BC1212/kg feed. Piglets fed Bacillus subtilis BC1212 increased in average daily weight gain and feed efficiency. In comparison with the control group, the fecal Bacillus subtilis were significantly increased and the fecal coliform bacteria were markedly reduced in the experimental group. In addition, Bacillus subtilis BC1212 had excellent acid and bile tolerance. The treatment of surfactin($50{\mu}g\;ml^{-1}$) in lipopolysaccharide(LPS)-stimulated swine peripheral blood mononuclear cells(PBMCs) for 6 h showed a significant inhibitory effect on INF-$\gamma$, TNF-$\alpha$ and NO secretion(p<0.05) in comparison with LPS treatment alone but not on IL-10 secretion, with levels of secreted IL-10 similar to those secreted by PBMCs stimulated with LPS alone. Supplementation with surfactin in combination with Bacillus subtilis BC1212 in diets improved the ecosystem of gastrointestinal tract by increasing probiotic population and enhanced the systemic immune response in weaned piglets.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1211-1212
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1211-1212
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• 2011

• Current Applied Physics
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• v.18 no.11
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• pp.1212-1217
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• 2018

The electric field-induced modifications of magnetic anisotropy in CoFeB/MgO systems are studied using X-ray resonant magnetic scattering and magneto-optical Kerr effect. Voltage dependent changes of the magnetic anisotropy of -12.7 fJ/Vm and -8.32 fJ/Vm are observed for Ta/CoFeB/MgO and Hf/CoFeB/MgO systems, respectively. This implies that the interfacial perpendicular magnetic anisotropy is reduced (enhanced) when electron density is increased (decreased). X-ray resonant magnetic scattering measurements reveal that the small in-plane magnetic component of the remanent state of CoFeB/MgO systems with weak magnetic anisotropy changes depending on the applied voltage leading to modification of the magnetic anisotropy at the CoFeB/MgO interface.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1212-1217
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• 2003

Fifty-two Holstein cows with different phenotypes of $\kappa$-casein ($\kappa$-CN) and $\beta$-lactoglobulin ($\beta$-LG) were selected to provide weekly milk samples for heating at 30, 70, 75 and $80^{\circ}C$ for 2 min. Coagulating properties of heated milk samples measured as rennet clotting time, rate of curd firming and curd firmness at cutting were determined by a Formagraph. Milk samples were analysed for fat and casein. Least squares analyses of data, after adjustments were made for effect of milk casein and fat contents, indicated that although an increase in heating temperatures resulted in less desirable coagulating properties, the effect of milk types was inherent irrespective of heating temperatures. The shortest rennet clotting time (6.06 min), fastest rate of curd firming (5.61 min) and firmest curd (38.05 mm) were obtained from milk with the B variant for $\kappa$-CN and B variant for $\beta$ -LG when preheated at $30^{\circ}C$. It appears that milk bearing $\kappa$-CN B is more resistant to heat perturbation. All milk samples having the $\kappa$-casein AA (milk types AA/AA, AA/AB, AA/BB) did not have a measurable K20 value when preheated at $70^{\circ}C$. This effect was observed for $\kappa$-casein AB (milk types AB/AA, AB/AB, AB/BB) at $75^{\circ}C$ and $\kappa$-casein BB (milk types BB/AA, BB/AB, BB/BB) at $80^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.707-714
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• 2013

Microbially induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process that has various applications in remediation and restoration of a range of building materials. In the present investigation, five ureolytic bacterial isolates capable of inducing calcium carbonate precipitation were isolated from calcareous soils on the basis of production of urease, carbonic anhydrase, extrapolymeric substances, and biofilm. Bacterial isolates were identified as Bacillus megaterium, B. cereus, B. thuringiensis, B. subtilis, and Lysinibacillus fusiformis based on 16S rRNA analysis. The calcium carbonate polymorphs produced by various bacterial isolates were analyzed by scanning electron microscopy, confocal laser scanning microscopy, X ray diffraction, and Fourier transmission infra red spectroscopy. A strain-specific precipitation of calcium carbonate forms was observed from different bacterial isolates. Based on the type of polymorph precipitated, the technology of MICCP can be applied for remediation of various building materials.