• Proceedings of the Materials Research Society of Korea Conference
• /
• 2009.05a
• /
• pp.56.1-56.1
• /
• 2009

The intermediate operating temperature of solid oxide fuel cells (IT-SOFCs) have achieved considerable importance in the area of power fabrication. This is because to improve materials compatibility, their long-term stability and cost saving potential. However, to conserve rational cell performance at reduced-temperature regime, cathode performance should be obtained without negotiating the internal resistance and the electrode kinetics of the cell. Recently, double perovskite structure cathodes have been studied with great attention as a potential material for IT-SOFCs. In this study, double-perovskite structured cathodes of $GdBaCoCuO_{5+\delta}$, $GdBaCo_{2/3}Cu_{2/3}Fe_{2/3}O_{5+\delta}$ compositions and $(1-x)GdBaCo_2O_{5+\delta}+xCe_{0.9}Gd_{0.1}O_{1.95}$ (x = 10, 20, 30 and 40 wt.%) composites were evaluated as the cathode for intermediate temperature solid oxide fuel cells(IT-SOFCs). Electrical conductivity of the cathodes were measured by DC 4-probe method, and the thermal expansion coefficient of each sample was measured up to $900^{\circ}C$ by a dilatometer study. Area specific resistances(ASR) of the $GdBaCo_{2/3}Cu_{2/3}Fe_{2/3}O_{5+\delta}$ cathode and 70 wt.% $GdBaCo_2O5+\delta$ + 30wt.% Ce0.9Gd0.1O1.95 composite cathode on CGO electrolyte substrate were analyzed using AC 3-probe impedance study. The obtained results demonstrate that double perovskite-based compositions are promising cathode materials for IT-SOFCs.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.4
• /
• pp.577-580
• /
• 2004

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.06a
• /
• pp.565-568
• /
• 2007

In this paper, we designed and fabricated a broadband probe with a double-ridged waveguide for broadband near-field measurements. An exponentially tapered ridge in the rectangular waveguide and a novel waveguide transition were used for broadband impedance matching. The probe has broadband characteristics and its measured impedance bandwidth is approximately 123% (4.17:1) in the range 12.0-50 GHz for standing wave ratios (SWR) < 3.0. The peak radiation gain range and nominal radar cross-section (RCS) are 5.7-14.3 dBi. The performance of this probe was verified using the measured results and is in good agreement with the simulated results.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.3
• /
• pp.823-826
• /
• 2013

A low-${\varepsilon}$ solid-state NMR(Nuclear Magnetic Resonance) probe was developed for the spectroscopic analysis of two-dimensional $^{15}N-^1H$ heteronuclear dipolar coupling in dilute membrane proteins oriented in hydrated and dielectrically lossy lipid environments. The system employed a 800 MHz narrow-bore magnet. A solenoid coil strip shield was used to reduce deleterious RF sample heating by minimizing the conservative electric fields generated by the double-tuned resonator at high magnetic fields. The probe's design, construction, and performance in solid-state NMR experiments at high magnetic fields are described here. Such high-resolution solid-state NMR spectroscopic analysis of static oriented samples in hydrated phospholipid bilayers or bicelles could aid the structural analysis of dilute biological membrane proteins.

• Proceedings of the KIEE Conference
• /
• 2006.07c
• /
• pp.1568-1569
• /
• 2006

An electric probe is a conductor inserted into the plasma, by which plasma density and electron temperature can be deduced from the collected current (I) versus applied voltage (V) to the probe. In RF plasma the I-V characteristics of electric probe is distorted due to the RF fluctuation of plasma potential, so that it is hard to measure the real plasma parameters, especially the electron temperature. To eliminate the RF fluctuation, several compensation methods are developed such as RF compensation probe, peak-to-peak method, asymmetric double probe. By comparing proposed methods, a suitable method is to be introduced in determining electron temperatures in RF plasma.

• Journal of Genetic Medicine
• /
• v.1 no.1
• /
• pp.45-50
• /
• 1997

Neuroblastoma, a pediatric malignant neoplasm of neural crest origin, has a wide range of clinical virulence. The mechanisms contributing to the development of neuroblastomas are largely unclear, but non-random chromosomal changes identified over the past years suggest the involvement of genetic alterations. Amplification of the human N-myc proto-oncogene is frequently seen either in extrachromosomal double minutes or in homogeneously staining regions (HSRs) of aggressively growing neuroblastomas. N-myc maps to chromosome 2 band 24, but HSR have never been observed at this band, suggesting transposition of N-myc during amplification. We have constructed and analyzed the region-specific painting probe for HSR in neuroblastoma IMR-32 to determine the derivative chromosomes. Microdissection was performed on HSR using an inverted microscope with the help of microglass needles and an micromanipulator. We pretreated the microdissected fragments with Topoisomerase I which catalyzes the relaxation of supercolled DNA, and performed two initial rounds of DNA synthesis with T7 DNA polymerase followed by conventional PCR to enable the reliable preparation of Fluorescent in situ hybridization probe from a single microdissected chromosome. With this method, it was possible to construct the region-specific painting probe for HSR. The probe hybridized specifically to the HSRs of IMR-32, and to 2p24, 2p13 of normal chromosome. Our results suggest there was coamplification of N-myc together with DNA of the chromosome 2p24 and 2p13. Moreover, the fluorescent signals for the amplified chromosomal regions in IMR-32 cells were also easily recognized at a Thus this painting probe can be applied to detect the similar amplification of N-myc in neuroblastoma tissue, and the probe pool for HSR may be used to identify the cancer-relevant genes.

• Journal of radiological science and technology
• /
• v.43 no.2
• /
• pp.87-96
• /
• 2020

This study examined the hygiene management of ultrasound probes by examining the cleaning tools for hygiene management of ultrasound probes, the presence or absence of wearing glove as a personal protective equipment, and the awareness of ultrasound probe hygiene. Parts 154 questionnaire about people working in the ultrasound room were surveyed and analyzed. The single gel removal tool of the ultrasound probe was most frequently used with a 48.7% cotton towel, and for double gel removal tools, the first gel removal tool was 42.4% cotton towel and the second gel removal tool was used with 57.6% wet tissue. Antimicrobial wipes were the most commonly used drug and instrument used in ultrasound hygiene management at 58.4%. According to the survey of the presence or absence of wearing glove during ultrasound examination, 46.8% were found to be unworn. When examining the intracavity ultrasound, 30.9% of those who do not wear glove and 61.0% of hygiene awareness of ultrasound probes are 'normal'. According to age, ultrasound probe gel removal tool was not significant difference(p>0.05). According to the working organization and the working department, it was significant difference to wearing gloves during ultrasound examination(p<0.05). Therefore, in order to properly sanitize the ultrasound probe, it is considered that a guideline for hygiene management of the ultrasound probe that fits the situation in Korea is necessary, and it is considered that thorough hygiene management training for inspector is necessary for efficient hygiene management of the ultrasound probe.

• Korean Journal of Optics and Photonics
• /
• v.6 no.2
• /
• pp.165-171
• /
• 1995

Infrared-Radio frequency double resonance (IRRFDR) and Infrared-Microwave double resonance (IRMWDR) spectroscopy have been used to probe a level of A symmetry for $CD_{3}$OH. Double resonance spectra of $CD_{3}$OH have been investigated over the range of 940 to 1020 $cm ^{-1}$ . Twenty K-type doublet transitions have been observed in both the radio frequency region, which covers 50 MHz to 1 GHz, and the microwave region, which covers 8 GHz to 12 GHz. The results propose new assignments of infrared (IR) absorption transitions and far-infrared (FIR) laser emission lines. These involve torsional excited levels and CO stretch states. Measurements of the A state splitting have permitted the determination of the asymmetry splitting parameters $S^{o}$(n, K) and $^{co}$ (n, K) for (n, K)=(0.3) and (1.3)

• Ceramist
• /
• v.21 no.2
• /
• pp.19-28
• /
• 2018

Coulomb drag is an effective probe into interlayer interaction between two electron systems in close proximity. For example, it can be a measure of momentum, phonon, or energy transfer between the two systems. The most exotic phenomenon would be when bosonic indirect excitons (electron-hole pairs) are formed in double layer systems where electrons and holes are populated in the opposite layers. In this review, we present various drag phenomena observed in different double layer electron systems, e.g. GaAs/AlGaAs heterostructures and two-dimensional material based heterostructures. In particular, we address the different behavior of Coulomb drag depending on its origin such as momentum or energy transfer between the two layers and exciton condensation. We also discuss why it is difficult to achieve electron-hole pairs in double layer electron systems in equilibrium.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.10b
• /
• pp.61-62
• /
• 2002

In order to clarify the contact mechanism between specimen surface and probe tip in the surface observation by the AFM (atomic force microscope) or the FFM (friction force microscope), several molecular dynamics simulations have been performed. In the simulation, a 3-dimensional simulation model is proposed where the specimen and the probe are assumed to consist of mono-crystal line copper and a carbon atom respectively and the effect of cantilever stiffness is also taken into considered. The surface observation process on a well-defined Cu{100} is simulated. The influences of cantilever stiffness on the reactive force images and the behavior of probe tip were evaluated. As a resuIt, several phenomena similar to those observed by the actual surface observation experiment, such as double-slip behavior and dispersion in the stick-slip wave period were observed.