검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 8,244

        710.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Salinity is a major abiotic stress for crop plants that cause reduced food production. The application of plant growth-promoting microorganisms can improve the adaptability of plants to biotic and abiotic stresses. Therefore, in the current study, we aimed to enhance the mitigation effects of artificially applied rhizobacterium Klebsiella variicola AY13 on salinity stress in Trifolium repens L. The results suggested that AY13 innately produced indole-3-acetic acid and accelerated the morphological adaptation of T. repens to salt stress conditions. Furthermore, AY13 promotes a Trp-dependent pathway for indole-3-acetic acid (IAA) production, as adding L-tryptophan (L-Trp) increased IAA production in pure culture. AY13 improved plant growth by maintaining relative water content and minimizing water loss in excised leaves. Moreover, AY13 inoculation significantly reduced the endogenous levels of abscisic acid and antioxidants such as glutathione and catalase. These results suggest that AY13 plays a crucial role in reprogramming stress-related metabolism and enhancing plant stress tolerance.
        4,000원
        711.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Protoplasts were isolated from the primary leaves of lettuce (Lactuca sativa L.) seedlings 10 days after in vitro germination. The leaves were stripped and incubated in an enzyme mixture consisting of 1.2% Cellulase R-10 and 0.3% Macerozyme R-10 in cell and protoplast washing solution (CPW) overnight. The average protoplast yield was 8.25 x 106 protoplasts per g of fresh leaf tissue. When protoplasts were cultured at a density of 3.0 × 105 protoplasts/mL in agarose solid KM8P/KM8 medium, first and second divisions were observed in the protoplasts within a week. Protoplast-derived microcolonies formed after 4 weeks of culture, and visible colonies were present after 3 months of culture. Protoplast-derived microcalli were transferred to Murashige and Skoog medium supplemented with 2.0 mg/L kinetin and 0.1 mg/L NAA and incubated in the light for 3 weeks. They grew into callus, which then regenerated into plants after 7 weeks of culture. The regenerated plants grew as apparently normal flowering fertile plants.
        4,000원
        712.
        2022.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The current study, which consisted of two independent studies (laboratory and greenhouse), was carried out to project the hypothesis fungi-spray scheduling for leaf mold and gray leaf spot in tomato, as well as to evaluate the effect of temperature and leaf wet duration on the effectiveness of different fungicides against these diseases. In the first experiment, tomato leaves were infected with 1 × 104 conidia·mL-1 and put in a dew chamber for 0 to 18 hours at 10 to 25°C (Fulvia fulva) and 10 to 30°C (Stemphylium lycopersici). In farm study, tomato plants were treated for 240 hours with diluted (1,000 times) 30% trimidazole, 50% polyoxin B, and 40% iminoctadine tris (Belkut) for protection of leaf mold, and 10% etridiazole + 55% thiophanate-methyl (Gajiran), and 15% tribasic copper sulfate (Sebinna) for protection of gray leaf spot. In laboratory test, leaf condensation on the leaves of tomato plants were emerged after 9 hrs. of incubation. In conclusion, the incidence degree of leaf mold and gray leaf spot disease on tomato plants shows that it is very closely related to formation of leaf condensation, therefore the incidence of leaf mold was greater at 20 and 15°C, while 25 and 20°C enhanced the incidence of gray leaf spot. The incidence of leaf mold and gray leaf spot developed 20 days after inoculation, and the latency period was estimated to be 14‒15 days. Trihumin fungicide had the maximum effectiveness up to 168 hours of fungicides at 12 hours of wet duration in leaf mold, whereas Gajiran fungicide had the highest control (93%) against gray leaf spot up to 144 hours. All the chemicals showed an around 30‒50% decrease in effectiveness after 240 hours of treatment. The model predictions in present study could be help in timely, effective and ecofriendly management of leaf mold disease in tomato.
        4,000원
        713.
        2022.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        담낭암은 드물지만 치명적인 악성 종양으로 초기에는 증상이 없어 대부분의 담낭암이 늦게 진단되고, 급속하게 인접 장기로 전이되기 때문에 예후가 불량하다. 따라서 담낭암을 조기에 발견하는 경우는 드물고, 담낭담석이나 용종으로 수술적 절제를 시행한 후 우연히 발견되는 때가 대부분이다. 저자들은 급성 무결석 담낭염 환자에서 초음파 내시경을 통해 비교적 조기에 담낭관암을 발견하여 성공적으로 치료할 수 있었던 증례를 경험하였다. 이에 문헌고찰과 함께 보고한다.
        4,000원
        716.
        2022.10 구독 인증기관·개인회원 무료
        With respect to the geologic repository, intrusion of groundwater has been considered as a major factor that can transfer radionuclides to the natural environment. Moreover, the migration of radionuclides in the natural groundwater system is significantly influenced by the interaction between the radionuclides and groundwater constituents. Among various hydrogeochemical reactions, hydrolysis is one of the major reactions that can affect the aqueous solubility of radionuclides. Therefore, a precise understanding of relevant chemical thermodynamic behavior is of cardinal importance for the reliable prediction of migration/retardation behavior of radionuclides in the natural groundwater system. The objective of the present work is to investigate the solubility behavior of Nd(OH)3(s) to provide relevant chemical thermodynamic data of Nd(III) as a chemical analogy of major radiotoxic elements such as Am(III) and Cm(III). All the experiments were performed with Ar gas-filled glovebox under inert atmospheric condition. The aqueous Nd(III) solution was prepared by dissolution of 0.5 g NdCl3·6H2O (Sigma-Aldrich) in 10 ml of deionized water. The Nd(III) solid phase was precipitated by dropwise addition of ca. 10 ml of 4 M NaOH (Sigma-Aldrich). The Nd(III) precipitate was identified to be crystalline Nd(OH)3(s) nanorod by using XRD and TEM. For the solubility experiment, the solid Nd(OH)3(s) was equilibrated at the pH range from 5.0 to 9.0 at 0.1 M NaCl condition. The total concentration of the Nd(III) was quantified by using UV/Vis absorption spectroscopy and ICP-MS after the phase separation. In the present work, the solubility behavior of the solid Nd(OH)3(s) phase was investigated by using colorimetric analysis. The chemical thermodynamic data obtained in this study are expected to enhance the reliability of solubility prediction for the trivalent lanthanides and actinides.
        717.
        2022.10 구독 인증기관·개인회원 무료
        According to the Nuclear Safety and Security Commission (NSSC) Notice No. 2021-26 “Delivery Regulations for the Low- and Intermediate Level Radioactive Waste (LILW)”, the activity of 3H, 14C, 55Fe, 58Co, 60Co, 59Ni, 63Ni, 90Sr, 94Nb, 99Tc, 129I, 137Cs, 144Ce, and gross alpha must be identified. Currently, the scaling factor of the dry active waste (DAW) for LILW is applied as an indirect evaluation method in Korea. The analyses are used the destructive methods and 55Fe, 60Co, 59Ni, 63Ni, 90Sr, 94Nb, 99Tc, and 137Cs, which are classified as nonvolatile nuclides, are separated through sequential separation and then measured by gamma detector, liquid scintillation counter (LSC), alpha/beta total counter (Gas Proportional Counter, GPC), and ICP-MS. We will introduce how to apply the existing nuclide separation method and improve the measurement method to supplement it.
        718.
        2022.10 구독 인증기관·개인회원 무료
        The Korea Atomic Energy Research Institute operates the Nuclear Cycle Experimental Research Facility which has radiation controlled area in the laboratory with the aim of realizing pyroprocessing technology. In this Facility, depleted Uranium feed material and a depleted Uranium mixed with some surrogate material are used for performing experiments. Therefore the facility is using uranium, users should be careful of radiation. This paper will explain the radiation protection of the Nuclear Cycle Experimental Research facility and will also explain how much alpha radiation comes out from the facility. The RMS (Radiation Monitoring System) detector is made by CANBERRA and the model name is ICAM. ICAM RMS is the detector which can detect Alpha Radiation by absorbing the air in the facility. The RMS detector is installed in the HVAC room on the third floor to check the air contamination through the chimney. The RMS is connected to the air ventilation line for detecting Alpha radiation in the whole facility. Experiment was performed for two weeks to check the radiation level and the air ventilation fan continued to operate 24 hours a day. the results are below the required value which is 0.1 Bq/m3, indicating that the facility is safe in terms of radiation safety management.
        719.
        2022.10 구독 인증기관·개인회원 무료
        The dimensioning machine installed in the hot cell has been used for 20 years. It has been used for a long time so it was often malfunction due to aging and radiation. In addition, some parts of apparatus were discontinued and there were a lot of problems in maintenance and repair. In the old measuring system, the operator’s subjectivity was much involved. The process of control the focal length (distance between lens and specimen) by operator’s sense is a good example. The existing dimensioning machine was the Kh-7700 of Hirox Co., Ltd. As the equipment had been used for a longtime, additional utilities such as jigs, lighting module and servo motors have been customized and used. The same company’s apparatus was selected for the reasons that it did not need to manufacture a new utility so it could save the cost of radioactive waste disposal for existing utilities and its radiation resistance which has been used for 20 years in radiation environment. Lighting, standing, stage, controllers, cables and so on had been customized to provide remote control in hot cell. The installation was completed in March of this year in hot cell and has been successfully used until now. Through the improvement of dimensioning machine, an auto-focusing and multi-focusing were available. Therefore, they made it possible to produce high quality data and improve the accuracy of data. And this research could be a good example of how hot cell devices can be built and customized to achieve remote control.
        720.
        2022.10 구독 인증기관·개인회원 무료
        As the decommissioning and decontamination (D&D) of nuclear power plants (NPPs) has actively proceeded worldwide, the management of radiation exposure of workers has become more critical. Radioactive aerosol is one of the main causes of worker exposure, contributing to internal exposure by inhalation. It occurs in the process of cutting radioactive metal structures or melting radioactive wastes during D&D, and its distribution varies according to decommissioning strategies and cutting methods. Among the dominant radionuclides in radioactive aerosols, Fe-55 is known to be the most abundant. Fe-55, which decays by electron capture, is classified as a difficult-to-measure (DTM) radionuclide because its emitted X-rays have too low energy to measure directly from outside of the container. Generally, for measuring DTM nuclides, the liquid scintillation counting (LSC) method and the scaling factor (SF) method are used. However, these methods are not suitable for continuous monitoring of the D&D workplace due to the necessity of sampling and additional analysis. The radiation measurement system that can directly measure the radionuclides collected at the aerosol filter could be more useful. In this study, as preliminary research on developing the radioactive aerosol monitoring system, we fabricated a gamma-ray spectrometer based on a NaI (Tl) scintillator and measured the energy spectrum of Fe-55. A beryllium window was applied to the scintillator for X-ray transmission, and the Fe-55 check source was directly attached to the scintillator assuming that the aerosol filter was equipped. 5.9 keV photopeak was clearly observed and the energy resolution was estimated as 44.10%. Also, the simultaneous measurement with Cs-137 was carried out and all the peaks were measured.