• Journal of IKEEE
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• v.22 no.2
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• pp.413-419
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• 2018

An UWB(Ultra Wide Band) antenna with band rejection characteristics is designed and implemented. A planar radiation patch with slot, parasitic elements on both sides of strip and ground plane on back side consist the proposed antenna. The slot in the radiation patch and parasitic elements contribute corresponding bands rejection characteristics. The slot contributes for WiMAX(World interoperability for Microwave Access, 3.30~3.70 GHz) band rejection and parasitic elements contribute for X-Band(7.25~8.395 GHz) rejection. Ansoft's HFSS(High Frequency Structure Simulator) was used to design the proposed antenna and performance simulations. Simulation result showed VSWR(Voltage Standing Wave Ratio) less than 2.0 for UWB band except for dual rejection bands of 3.30~3.86 GHz and 7.21~8.39 GHz. And VSWR measurement result for the implemented antenna shows less than 2.0 for 3.10~10.60 GHz band except dual rejection bands of 3.25~3.71 GHz and 7.25~8.46 GHz.

• Journal of the Korean Chemical Society
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• v.23 no.3
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• pp.141-151
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• 1979

The selective absorption of metal ions by chelating agent-loaded resins was studied in aqueous media. The resins were prepared by loading the conventional anion exchange resin, Dowex 1-X8 (50 to 100 mesh) with chelating agents containing sulfonic group, such as 8-hydroxy-quinoline-5-sulfonic acid (HQS) and 7-nitroso-8-hydroxyquinoline-5-sulfonic acid (NHQS). The stability of the resin was markedly influenced by the following factors; (1) the affinity and concentration of anions in the external solution, (2) the pH of the media. The optimum conditions for the absorption of metal ions were determined with respect to the pH, shaking time, and the effect of anion concentration in the medium. Under the optimum condition the order of the absorption of metal ions such as Fe(Ⅲ), Cu(Ⅱ), Pb(Ⅱ), and Zn(Ⅱ) was in accord with that of the stability constants of the chelates. The total capacities of the resins were found in the range of 0.6∼1.6 mmole metal per gram.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2249-2252
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• 2011

Two new carborane complexes containing closo- or nido-carborane diphosphine ligands with the formula: complex $[Hg(7,8-(PPh_2)_2-7,8-C_2B_9H_{10})_2]$ $CH_2Cl_2$ (1) and $[Ag_2({\mu}-Cl)_2(1,2-(P^iPr_2)_2-1,2-C_2B_{10}H_{10})_2]$ (2) have been synthesized and characterized by elemental analysis, 1H and 13C NMR spectroscopy and X-ray structure determination. The X-ray structure analyses revealed that the carborane diphosphine ligand was degraded from closo-1,2-$(PPh_2)_2-1,2-C_2B_{10}H_{10}$ to nido-[$7,8-(PPh_2)_2-7,8-C_2B_9H_{10}]^-$ in complex 1, while the closo nature of the starting ligand $1,2-(P^iPr_2)_2-1,2-C_2B_{10}H_{10}$ was retained in complex 2. In either of the two complexes, the carborane diphosphine ligand was coordinated bidentately to the Hg(II) or Ag(I) center through its two phosphorus atoms, therefore forming a five-member cheating ring between the carborane ligand and the metal center. The coordination geometry of the metal atom is distorted tetrahedron formed by $P_4$ unit in complex 1 and $P_2Cl_2$ unit in complex 2, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.393-400
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• 2012

The study was conducted to examine the effects of partially replacing soybean meal (SBM) by solid-state fermented cottonseed meal (FCSM) on growth performance, serum biochemical parameters and immune function of broilers. After inoculated with Bacillus subtilis BJ-1 for 48 h, the content of free gossypol in cottonseed meal was decreased from 0.82 to 0.21 g/kg. A total of 600, day-old male yellow-feathered broilers were randomly divided into four groups with three replicates of 50 chicks each. A corn-SBM based control diet was formulated and the experimental diets included 4, 8 or 12% FCSM, replacing SBM. Throughout the experiment, broilers fed 8% FCSM had higher (p<0.05) body weight gain than those fed 0, 4 and 12% FCSM. The feed intake in 8% FCSM group was superior (p<0.05) to other treatments from d 21 to 42. On d 21, the concentration of serum immunoglobin M in the 4% and 8% FCSM groups, as well as the content of complements (C3, C4) in 8% FCSM group were greater (p<0.05) than those in the SBM group. Besides, birds fed 8% FCSM had increased (p<0.05) serum immunoglobin M, immunoglobulin G and complement C4 levels on d 42 compared with bird fed control diet. No differences (p>0.05) were found between treatments regarding the serum biochemical parameters and the relative weights of immune organs. In conclusion, FCSM can be used in broiler diets at up to 12% of the total diet and an appropriate replacement of SBM with FCSM may improve growth performance and immunity in broilers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.8
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• pp.830-838
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• 2003

In this paper, TX/RX dual operation microstrip single antenna for satellite communication is designed, analyzed, fabricated and measured. TX/RX frequency ranges are 14.0∼l4.5 GHz, 11.7∼12.75 GHz in respectively and vertical and horizontal polarizations are used for TX and RX. This antenna uses microstrip direct feeding for RX and aperture coupled strip-line feeding for TX and accommodates stacked elements for a high directivity and wide impedance bandwidth. In an analysis of single element, FDTD and MOM was compared and FDTD analysis was more accurate because of the consideration of finite structure and imperfect two ground planes. The proposed structure facilitates generally to an extension of two dimensional array and lower an unwanted radiation by strip-line feed in TX. TX/RX 8${\times}$4 array has a return loss below -10 dB, -14 dB in TX, RX respectively and a gain ranging from 19.1∼20.7 dB in TX, 21.2∼21.8 dB in RX which has a radiation efficiency of 43∼5l %, 52∼57 %.

• Journal of the Mineralogical Society of Korea
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• v.30 no.4
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• pp.187-194
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• 2017

In this study, marble that consist mainly of calcite were used for applicability evaluation after treated with consolidant such as alkoxysilane series of 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%. The position and intensity of X-ray diffraction peaks are no change and increasing trend after treated with two consolidants. The results of scanning electron microscopic analysis, morphology of rope type and homogeneous surface of platy or leaflike form observed on the marble after treated with 0.8T0.2E1G_3wt0.08% and 1T1G_7wt0.08%, respectively. Brightness of surface after treated with consolidant are changing slightly dark. Shore hardness and ultrasonic velocity values show increasing after treated on the marble surface with two consolidants.

• Animal Bioscience
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• v.36 no.8
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• pp.1221-1227
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• 2023

Objective: The present study aimed to investigate the effect of dietary lutein on egg production, follicles, reproductive hormones, fertility, hatchability, and oxidative injury indexes of hens. Methods: Treatments consisted of a control diet (CON) and three lutein-supplementing diets at 25 (L1), 50 (L2), or 75 (L3) mg/kg of diet. Egg production was measured using 576 Arbor Acres breeder hens at 61 to 65 wk and follicles grades, reproductive hormones, fertility, hatchability, tissue lutein contents, and oxidative injury indexes were determined at 65 wk. Results: The results showed that at 65 wk, lutein- supplementing diets increased (p<0.05) egg production, follicular grades, fertility, hatchability, estradiol (E2), luteinizing hormone, progesterone (PROG), lutein content in the serum and yolk, compared to CON. L2 and L3 showed more pronounced (p<0.05) effects on egg production, PROG, and yolk lutein content than L1. With the increase of lutein doses from 25 to 75 mg/kg, there were linear increases (p<0.05) in egg production, lutein content, and PROG, and a quadratic trend (p<0.05) in E2. For the oxidative injury products, lutein-supplementing diets decreased (p<0.05) malondialdehyde (MDA) and protein carbonyl (PCO) in the serum, MDA and 8-hydroxy 2 deoxyguanosine (8-OHdG) in the yolk. There were linear decreases (p<0.05) in 8-OHdG in the serum, MDA, PCO, and 8-OHdG in the yolk, a quadratic trend (p<0.05) on serum 8-OHdG. Conclusion: It is concluded that lutein supplementation can improve egg production and fertility by beneficially regulating reproductive hormones and oxidative status in aged hens.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.570-575
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• 2014

This study was conducted to compare the effects of two forms of radiation (electron and X-ray; generated by an electron beam accelerator) on the conformation and antigenic properties of hen's egg albumin, ovalbumin (OVA), which was used as a model protein. OVA solutions (2.0 mg/mL) were individually irradiated by electron beam or X-ray at the absorbed doses of 0 (control), 2, 4, 6, 8, and 10 kGy. No differences between the two forms of radiation on the structural properties of OVA were shown by spectrometric and electrophoretic analyses. The turbidity of OVA solution increased and the main OVA bands on polyacrylamide gels disappeared after irradiation, regardless of the radiation source. In competitive indirect enzyme-linked immunosorbent assay, OVA samples irradiated by electron beam or X-ray showed different immunological responses in reactions with monoclonal and polyclonal antibodies (immunoglobulin G) produced against non-irradiated OVA. The results indicate that electron beam irradiation and X-ray irradiation produced different patterns of structural changes to the OVA molecule.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.503-507
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• 1998

Sintering behavior and dielectric peroperties of $xCaTiO_3-La(Zn_{1/2}Ti_{1/2})O_3$ system were investigated for better understanding of the microwave dielectric materials. In $xCaTiO_3-(1-x)La(Zn_{1/2}Ti_{1/2})O_3$ systems, solid solution type was focused as a function of composition(x=0.4-0.6) and sintered density. With increasing the sintered density, the relative dielectric constant was decreased and Q value was increased and then saturated. In solid solution type, dielectric constant was increased with increasing $CaTiO_3$ content. In $0.5\;CaTiO_3-0.5\; La(Zn_{1/2}Ti_{1/2})O_3$ case, dielectric constant(=48) and temperature coefficient of resonace frequency$(=-1 ppm/^{\circ}C$) were obtained.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.346-350
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• 2002

The effect of Ca-doping on the superconducting properties of Nd-Ba-Cu-O bulk superconductors, fabricated by the oxygen-controlled melt growth process, has been systematically investigated. Various c-axis textured bulk samples were grown using precursors with the nominal compositions of N $d_{1.8-x}$C $a_{x}$B $a_{2.4}$C $u_{3.4}$ $O_{y}$ (x = 0.00, 0.02, 0.05, 0.10, 0.15) in a reduced oxygen atmosphere of 1% $O_2$ in Ar. Magnetization measurements revealed that the critical temperatures( $T_{c}$) were almost linearly depressed from 95K to 86K with increasing the Ca dopant from x = 0.0 to 0.15, respectively, and thus critical current densities( $J_{c}$) at 77K and for H//c-axis of specimens were gradually degraded with increasing x. Compositional analyses revealed that although the amounts of the Ca dopant both in NdB $a_2$C $u_3$ $O_{y}$(Nd123) and N $d_4$B $a_2$C $u_2$ $O_{10}$(Nd422) were increased with increasing x, only less than half of the initial Ca compositions were detected in melt-grown Ca-doped Nd-Ba-Cu-O bulk crystals. The supression of $T_{c}$ is attributed to an increased Nd substitution for the Ba site in the Nd123 superconducting matrix with increasing the amount of the Ca dopant.t.opant.t.t.t.t.t.