Radionuclide analysis methods must be secured in the event of emergencies such as the discovery of unknown nuclear material or nuclear accidents in neighboring countries or Korea. Most institutions in Korea are in their early stages of radionuclide analysis method development and do not even have Radiation Controlled Areas where they can handle the samples safely. Some institutions such as the Korea Atomic Energy Research Institute have the ability to perform radionuclide analysis for nuclear facilities or verification of nuclear activities. In Korea, it is necessary to secure nuclide analysis technology to enable independent verification in times of emergency or need. This paper analyzes uranium as the target nuclide using alpha spectrometer and TIMS. Alpha spectrometer detects alpha particles emitted from uranium samples and measures the concentration of uranium isotopes. This method has a high selectivity that distinguishes it from other elements, and accurate measurements can be made even when uranium samples are mixed with other elements. In addition, there is minimal interference from other radioactive isotopes in the sample, and the sample preparation is simple, resulting in relatively short analysis times. In contrast, TIMS detects ionized uranium ions by heating the uranium sample. This method may have potential interference from other elements and may take relatively longer analysis times. However, TIMS has high sensitivity and accuracy and can detect various elements other than uranium, making it suitable for various analyses. Therefore, when analyzing uranium, it is recommended to select and use the appropriate device according to the purpose, as both alpha spectrometer and TIMS have their pros and cons. Furthermore, by using both devices in parallel, more accurate and reliable results can be obtained. This paper aims to compare the analysis methods of alpha spectrometer and thermal ionization mass spectrometry, which are widely used for nuclide analysis in unknown nuclear materials.

Scale and rust generation in water pipes is a common phenomenon when cast iron water pipes have been used for a long time. A physical water treatment device is known among various means for suppressing rust in a water pipe, and a zinc ionization device for putting zinc metal into a pipe and emitting the zinc cation into water is one of such devices. This research measured the amount of zinc ion generated, which is known to exhibit an effect of inhibiting rust and scale generation in a pipe, and examined the scale and rust inhibition effect of the ionization device installed for ground or building water supply. In the case of distilled water, the concentration of zinc ion increased by circulating water in the ionization device several times, and it was verified to be hundreds of μg/L, and in the case of discharging ground or tap water, it was verified to be tens of μg/L. In addition, a verification pipe was installed to confirm the change inside the pipe before and after installation of the zinc ionization device, and the internal condition of the pipe was observed 3 months to several years after installation. It was confirmed that the corrosion area of the surface of the pipe was no longer increased by installing a corrosion inhibitor, and if the pipe was already filled with corrosion products, the amount of corrosion products gradually decreased every year after installation. The phenomenon of fewer corrosion products could be interpreted as expanding the space in the pipe due to the corrosion product as Fe2O3 adhered to the inner surface of the pipe and turned into a smaller black Fe3O4. In addition, we found that scale such as CaCO3 together in the corrosion by-products gradually decreased with the attachment of the ionization device.

본 연구는 조제유류 중 지방산에 대해 최신 분석법을 마련하고자 수행하였다. 조제유류 중 지방산 함량 분석을 위해 GC를 이용한 분석법을 확립하고 시중에 유통 중인 제품을 대상으로 적용성을 검토하였다. 분석법 검증은 특이성, 직선성, 검출한계 및 정량한계, 정확성, 정밀성에 대해 수행되었다. Linoleic acid 및 α-linolenic acid의 0.1-5 mg/ mL 농도범위에서 R2=0.999 이상의 우수한 직선성을 확인할 수 있었다. Linoleic acid 및 α-linolenic acid의 LOD는 각각 0.06 mg/mL, 0.01 mg/mL, LOQ는 각각 0.16 mg/mL, 0.03 mg/mL였다. 표준인증물질 분석을 통해 정확성을 검토 하였으며, linoleic acid 및 α-linolenic acid의 회수율은 각각 100.8%와 101.1%로 확인하였다. 정밀성을 검토한 결과 시료 채취량에 따른 반복성은 linoleic acid 1.4-2.9%, α- linolenic acid 1.1-2.7%이었고, 실험실간 재현성은 각각 2.8%, 1.5%임을 확인하였다. 본 연구에서 확립된 분석법을 적용하여 국내 유통 중인 조제유류 및 조제식 제품 12건에 대해 적용성 검토를 실시한 결과 전체 시료에서 분석이 용이 하였으며, 모두 기준·규격에 적합함을 확인하였다. 본 결과로부터 확립된 GC를 이용한 분석법은 조제유류 중 지방산 함량을 확인하기에 적합함을 확인하였으며 국내 식품 영양 성분의 관리 기반을 강화하는데 기여할 것으로 사료된다.

We study the radio properties at 1.4 GHz of Seyfert galaxies with strong forbidden highionization lines (FHILs), selected from the Sloan Digital Sky Survey – a large-sized sample containing nearly equal proportion of diverse range of Seyfert galaxies showing similar redshift distributions compiled by Gelbord et al. (2009) using the Very Large Array survey images. The radio detection rate is low, 49%, which is lower than the detection rate of several other known Seyfert galaxy samples. These galaxies show low star formation rates and the radio emission is dominated by the active nucleus with ≤10% contribution from thermal emission, and possibly, none show evidence for relativistic beaming. The radio detection rate, distributions of radio power, and correlations between radio power and line luminosities or X-ray luminosity for narrow-line Seyfert 1 (NLS1), Seyfert 1 and Seyfert 2 galaxies are consistent with the predictions of the unified scheme hypothesis. Using correlation between radio and [O III]  5007°A luminosities, we show that ∼8% sample sources are radio-intermediate and the remaining are radio-quiet. There is possibly an ionization stratification associated with clouds on scales of 0.1–1.0 kpc, which have large optical depths at 1.4GHz, and it seems these clouds are responsible for free–free absorption of radio emission from the core; hence, leading to low radio detection rate for these FHIL-emitting Seyfert galaxies.

새싹은 영양분이 풍부한 식품이다. 하지만 생산 과정에서 종피에 있는 미생물에 의한 오염 가능성이 존재한다. 이 실험의 목적은 음이온 처리가 새싹의 생장과 살균에 미치는 효과를 구명하는 것이다. 음이온 처리는 4종류의 새싹의 생장과 살균효과에 긍정적인 효과를 보였다. 대조구에 비해 음이온 처리한 적양배추와 케일 새싹의 배축길이는 약 1.26배 증가하였으며, 상추, 적양배추, 케일 유근의 길이는 1.4~1.6배 증가하였다. 모든 새싹의 생체중은 음이온 처리했을 때 대조구에 비해 16.0~38.5% 유의적으로 증가하였다. 유근의 활력 또한 음이온 처리가 대조구에 비해 유의적으로 높은 수치를 보였다. 음이온 처리된 상추, 적양배추, 다채 새싹의 일반 세균 수는 대조구에 비해 각각 41%, 66%, 19% 감소하였으며, 배수되는 물의 세균 수 또한 감소되었다. 결국 음이온처리는 새싹의 생장을 향상시켰으며, 동시에 살균하는데도 효과적이었다.

차 중에 있는 살균제 tridemorph의 잔류량을 검사하기 위해 LC-ESI-MS/MS를 이용한 정확하고 감도가 좋은 분석방 법을 개발하였다. Tridemorph 잔류물은 샘플을 수화한 후 acetonitrile로 추출하고, NaCl을 이용한 액-액 분배, NH2 카트리지 정제를 거쳐 기기분석을 수행하였다. 직선성은 0.02~1.0 μgmL−1 범위에서 상관계수(r2) 0.9999로 높은 직선 성을 보였다. 0.02와 0.05 mgkg−1 처리수준으로 회수율을 실험한 결과는 75.0~84.7% 이었으며, 상대표준편차는 10% 미만이었다. 분석방법의 검출한계와 정량한계는 각각 0.01 와 0.02 mgL−1 이었다. 이러한 결과들을 통해 확립된 분석법은 차 중 tridemorph의 잔류량 분석에 적합함을 확인할 수 있었다.

Proteomics may help to detect subtle pollution-related changes, such as responses to mixture pollution at low concentrations, where clear signs of toxicity are absent. Also proteomics provide potential in the discovery of new sensitive biomarkers for environmental pollution. We utilized SELDI-TOF MS (surface enhanced laser desorption. / ionization time-of-flight mass spectrometry) to analyze the proteomic profile of Heterocypris incongruens exposed to several heavy metals (lead, mercury, copper, cadmium and chromium) and pesticides (emamectin benzoate, endosulfan, cypermethrin, mancozeb and paraquat dichloride). Several highly significant biomarkers were selected to make a model of classification analysis. data sets obtained from H. incongruens exposed to pollutants were investigated for differential protein expression by SELDI-TOF MS and decision tree classification. Decision tree model was developed with training set, and then validated with test set from profiling data of H. incongruens. Machine learning techniques provide a promising approach to process the information from mass spectrometry data. Even thought the identification of protein would be ideal, class discrimination does not need it. In the future, this decision tree model would be validated with various levels of pollutants to apply field samples.

This study was conducted to examine the potential of surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) to screen Tetranychus urticae resistance to pyridaben and dicofol. T. urticae is one of the most important pests in greenhouse and orchard, and huge expense is needed to control because of its strong resistance to acaricides. Consequently speedy and accurate monitoring of acaricidal resistance is the key factor of IPM for T. urticae. SELDI-TOF MS is a novel approach to biomarker discovery that combines two powerful techniques: chromatography and mass spectrometry. It can provide a rapid protein expression profile of acaricidal sensitive and resistant T. urticae. In this study we had different protein and peptide patterns between sensitive and resistant strains to pyridaben and dicofol. In the future this results could be a useful data to develop a good monitoring tool of site and host specific mite resistance to various acaricides.

LC-DAD-ESI/MS를 이용하여 국내 자색벼 품종에 대해 개별 안토시아닌 조성 및 함량을 평가한 결과는 다음과 같다. 1. 자색벼 품종에서 분리된 모든 개별 안토시아닌의 화학구조는 MS fragment 패턴을 확인하여 cyanidin을 base로 한 unknown 화합물 1종을 포함, cyanidin 3,5-diglucoside, cyanidin 3-glucoside, peonidin 3-glucoside의 총 4가지 개별성분이 분리 및 동정되었다. 2. Cyanidin 3-glucoside 및 peonidin 3-glucoside이 주요성분으로 cyanidin 3-glucoside의 경우 90% 이상의 가장 높은 함량 비중을 나타냈으며, 개별성분별 평균 함량은 cyanidin 3-glucoside > peonidin 3-glucoside > cyanidin 3,5-diglucoside > unknown(cyanidin based)의 순으로 나타났다. 3. 흑진주벼의 총 안토시아닌 함량은 408 mg/100 g으로 흑남벼보다 약 6배 정도 높은 함량을 나타내었다.

Bacillus thuringiensis (B. t.) strains are important microorganism because they produced a large amount of δ-endotoxin protein per bacterial cell and their toxins are highly toxic to Lepidoptera, Coleoptera, and Diptera depending on B. t. To date, more than a hundred Cry proteins have been identified and classified into 195 holotypes, based on the amino acid sequence identity. The Cry proteins or cry genes from the Korean native B. t. isolates in this study were not identified yet. The electrospray ionization of quadrupole time of flight mass spectrometry (ESI Q-TOF MS) was used to get the internal amino acid sequences of the endotoxin-spore culture mixtures of B. t. isolates, for which polymerase chain reaction (PCR) techniques were unable to detect the cognate genes. Most of Cry proteins seperated, excized, and extracted from the one dimensional - polyacrylamide gel electrophoresis (1D-PAGE), instead of 2D-PAGE, were matched with protein databases using MS-MASCOT search program. The internal amino acid sequences which were submitted to protein BLAST (basic local alignment search tool) had partially homology with the Cry protein databases. Hence, present data strongly suggest that the de novo amino acid sequencing and ESI Q-TOF/MS analysis along with MASCOT search could be used as a simple and rapid method for detection of novel Cry toxins from B. t. isolates and identification of B. t. isolates.

In this paper, the intensity ratio of [O I] λ6300 and Hα lines, which plays an important role in the study of warm (or diffuse) ionized interstellar medium, is calculated assuming collisional ionization equilibrium (or coronal equilibrium). The calculated ratio is compared with the previous works, and with the observations, obtained by Reynolds (1989) and Reynolds et al. (1998) with the Wisconsin Ha Mapper facility, toward the directions that sample the faint interstellar emission-line background. The comparison confirms that most of the Ha originates from nearly fully ionized regions along the lines of sight rather than from partially ionized H I clouds or layers of H II on the surfaces of H I clouds.

The effects of molecular structure on the redox properties of the organic electroluminescent materials (Ir(ppy)3 Ir(m-ppy)3 Ir(p-toly)3) were studied using cyclic voltammetry and spectroscopy. These iridium complexes show reversible oxidation and reduction on the electrode, which produce the symmetric cyclic voltammogram. It indicates that these materials are very stable under repetitive oxidation/reduction cycles. The electrochemically determined ionization potentia/electron affinity values are 5.4OeV/3.02eV for Ir(ppy)3, 5.36eV/2.96eV for Ir(m-ppy)3, and 5.35eV/2.97eV for Ir(p-toly)3 from the SCE(Standard Calomel Electrode). The electrically determined band gaps are 2.38eV (521nm), Ir(ppy)3, 2.4OeV (517nm), Ir(m-ppy)3, and 2.38eV (521nm). Ir(p-toly)3, which are similar with the optical band gaps. The position of methyl group on 2-phenylpyridine (ppy) effects do not influence much on the ionization potential, electron affinity, and band gap of Ir(ppy)3 derivatives.

The ionization degree of hydrogen is crucial in the physics of the plasma in the solar chromosphere. It specifically limits the range of plasma temperatures that can be determined from the Hα line. Given that the chromosphere greatly deviates from the local thermodynamic equilibrium (LTE) condition, precise determinations of hydrogen ionization require the solving of the full set of non-LTE radiative transfer equations throughout the atmosphere, which is usually a formidable task. In many cases, it is still necessary to obtain a quick estimate of hydrogen ionization without having to solve for the non-LTE radiative transfer. Here, we present a simple method to meet this need. We adopt the assumption that the photoionizing radiation field changes little over time, even if physical conditions change locally. With this assumption, the photoionization rate can be obtained from a published atmosphere model and can be used to determine the degree of hydrogen ionization when the temperature and electron density are specified. The application of our method indicates that in the chromospheric environment, plasma features contain more than 10% neutral hydrogen at temperatures lower than 17,000 K but less than 1% neutral hydrogen at temperatures higher than 23,000 K, implying that the hydrogen temperature determined from the Hα line is physically plausible if it is lower than 20,000 K, but may not be real, if it is higher than 25,000 K. We conclude that our method can be readily exploited to obtain a quick estimate of hydrogen ionization in plasma features in the solar chromosphere.

In solstices during the solar minimum, the hemispheric difference of the equatorial ionization anomaly (EIA) intensity (hereafter hemispheric asymmetry) is understood as being opposite in the morning and afternoon. This phenomenon is explained by the temporal variation of the combined effects of the fountain process and interhemispheric wind. However, the mechanism applied to the observations during the solar minimum has not yet been validated with observations made during other periods of the solar cycle. We investigate the variability of the hemispheric asymmetry with local time (LT), altitude, season, and solar cycle using the electron density taken by the CHAllenging Minisatellite Payload satellite and the global total electron content (TEC) maps acquired during 2001–2008. The electron density profiles provided by the Constellation Observing System for Meteorology, Ionosphere, and Climate satellites during 2007–2008 are also used to investigate the variation of the hemispheric asymmetry with altitude during the solar minimum. During the solar minimum, the location of a stronger EIA moves from the winter hemisphere to the summer hemisphere around 1200–1400 LT. The reversal of the hemispheric asymmetry is more clearly visible in the F-peak density than in TEC or in topside plasma density. During the solar maximum, the EIA in the winter hemisphere is stronger than that in the summer hemisphere in both the morning and afternoon. When the location of a stronger EIA in the afternoon is viewed as a function of the year, the transition from the winter hemisphere to the summer hemisphere occurs near 2004 (yearly average F10.7 index = 106). We discuss the mechanisms that cause the variation of the hemispheric asymmetry with LT and solar cycle.