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1.
Jung-Hoon Choi In-Hak Cho Hee-Chul Eun Hwan-Seo Park Yung-Zun Cho Ki-Rak Lee Geun-Il Park Song-Hyun Kim Chang-Ho Shin Jong-Kyung Kim 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1731-1738
The pyrochemical process, which uses a dry method to recycle used nuclear fuel generates waste LiCl–KCl salt containing radioactive lanthanide elements. To reuse LiCl–KCl salt, the lanthanide elements are separated through a precipitation method promoted by oxygen sparging and the separated fission product of lanthanide oxide should be fabricated into durable wasteforms sustainable for several 1,000 years to store in a final geological repository. Herein, we report the fabrication of a borosilicate glass based wasteform with a glass matrix of SiO2–Al2O3–B2O3 having a high waste loading of 50 wt% lanthanide oxide. Th physical properties of four kinds of wasteforms having a different lanthanide oxide waste composition were evaluated. To investigate the long-term physical stability of each sample having 50 wt% lanthanide oxide waste loading, time–temperature–transformation (TTT) test was conducted at 500 and 700 °C for 60 and 180 h, and the physical properties were evaluated after each TTT test. 相似文献
2.
Jang Junhyuk Kim Tack-Jin Eun Hee-Chul Kim Gha-Young Lee Sungjai 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):649-654
Journal of Radioanalytical and Nuclear Chemistry - U recovery test was performed on a Zn-U alloy to confirm the feasibility of Zn as an alternative cathode material. An evaporation test of pure Zn... 相似文献
3.
Eun Hee-Chul Yang Hee-Chul Kim Hyung-Ju Kim Sung-Jun Jeon Min-Ku Lee Keun-Young Seo Bum-Kyoung 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3735-3744
Journal of Radioanalytical and Nuclear Chemistry - CaCO3 powder containing C-14, which has a long half-life, is generated from the treatment process of spent activated carbons from the air cleaning... 相似文献
4.
Young-Gu Cho Dae-Kwang Park Dae-Won Park Hee-Chul Woo Jong-Shik Chung 《Research on Chemical Intermediates》2002,28(5):419-431
The selective oxidation of hydrogen sulfide containing excess water and ammonia was studied over vanadium-bismuth mixed oxide catalysts. The investigation was focused on understanding the complex reaction steps and the roles of each metal oxide. Therefore, supported V2O5/TiO2, V-Bi-O/TiO2 catalysts and a mechanical mixture of V2O5 + Bi2O3 were tested in the reaction. Ammonia reacted either with H2S or SO2, produced from the oxidation of H2S. Water vapor promoted the reaction of ammonia and SO2. Strong synergistic phenomena in catalytic activity were observed for the mechanically mixed catalyst of V2O5 and Bi2O3. V-Bi-O/TiO2 catalyst showed very high H2S conversion without any considerable emission of SO2. Temperature-programmed studies (TPR and TPO), XRD and Raman analyses revealed that the high catalytic performance of V-BiO/TiO2 catalyst originated from the high redox capacity of the bismuth vanadate phase. 相似文献
5.
Hwan-Seo Park In-Tae Kim Yong-Jun Cho Mi-Sook Son Hee-Chul Eun 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):267-272
Radioactive molten salt generated from a pyrochemical process to separate reusable U and TRU elements is one of problematic
wastes to manage for a final disposal. For the minimization of final waste, it is desirable to selectively remove radionuclides
from the waste salts. In this paper, structural change of some zeolites in a series of molten salt systems and its removal
behavior of CsCl was investigated. Zeolite-4A(LTA) was transformed into LiAlSiO4 and Li-sodalite with the mol-fraction of LiCl in LiCl–KCl system at 650 °C while it was not changed in NaCl–KCl at 750 °C,
regardless of mol-fraction of metal chloride. Other commercial zeolite with specific structure (FAU) had the same trends on
the structural stability in molten salt system. From the Cs removal experiments, the decomposed zeolitic materials in molten
salt lost their removal ability of Cs. In conclusion, a new selective material or method should be investigated or developed
for obtaining the validity on the separation of group I and II radionuclides from a molten waste salt because the zeolite
4A is unstable in the LiCl system and it also showed a low capacity in the LiCl–KCl phase. This paper gives basic information
on the removal of radionuclides from molten systems by using zeolitic materials. 相似文献
6.
Ahn HC Juranić N Macura S Markley JL 《Journal of the American Chemical Society》2006,128(13):4398-4404
We chose crambin, a hydrophobic and water-insoluble protein originally isolated from the seeds of the plant Crambe abyssinica, as a model for NMR investigations of membrane-associated proteins. We produced isotopically labeled crambin(P22,L25) (variant of crambin containing Pro22 and Leu25) as a cleavable fusion with staphylococcal nuclease and refolded the protein by an approach that has proved successful for the production of proteins with multiple disulfide bonds. We used NMR spectroscopy to determine the three-dimensional structure of the protein in two membrane-mimetic environments: in a mixed aqueous-organic solvent (75%/25%, acetone/water) and in DPC micelles. With the sample in the mixed solvent, it was possible to determine (>NH...OC<) hydrogen bonds directly by the detection of (h3)J(NC)' couplings. H-bonds determined in this manner were utilized in the refinement of the NMR-derived protein structures. With the protein in DPC (dodecylphosphocholine) micelles, we used manganous ion as an aqueous paramagnetic probe to determine the surface of crambin that is shielded by the detergent. With the exception of the aqueous solvent exposed loop containing residues 20 and 21, the protein surface was protected by DPC. This suggests that the protein may be similarly embedded in physiological membranes. The strategy described here for the expression and structure determination of crambin should be applicable to structural and functional studies of membrane active toxins and small membrane proteins. 相似文献
7.
We describe a novel real-time PCR method, which utilizes the in situ generated signal upon incorporation of a fluorogenic nucleotide. The method has been compared with a conventional method and evaluated for practical uses such as quantification of cDNA and malaria diagnosis. 相似文献
8.
Eun Hee-Chul Yang Hee-Chul Kim Hyung-Ju Kim Sung-Jun Lee Keun-Young Seo Bum-Kyoung 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):627-635
Journal of Radioanalytical and Nuclear Chemistry - Activated carbon wastes from the air cleaning system in a nuclear facility contain a long half-life value of 14C (5700 years). This 14C... 相似文献
9.
Genetic and expression alterations in association with the sarcomatous change of cholangiocarcinoma cells 总被引:1,自引:0,他引:1
Hee-Jung Yoo Bo-Ra Yun Jung-Hee Kwon Hyuk-Soo Ahn Min-A Seol Mi-Jin Lee Goung-Ran Yu Hee-Chul Yu BeeHak Hong KwanYong Choi Dae-Ghon Kim 《Experimental & molecular medicine》2009,41(2):102-115
Cholangiocarcinoma (CC) is an intrahepatic bile duct carcinoma with a high mortality rate and a poor prognosis. Sarcomatous change/epithelial mesenchymal transition (EMT) of CC frequently leads to aggressive intrahepatic spread and metastasis. The aim of this study was to identify the genetic alterations and gene expression pattern that might be associated with the sarcomatous change in CC. Previously, we established 4 human CC cell lines (SCK, JCK1, Cho-CK, and Choi-CK). In the present study, we characterized a typical sarcomatoid phenotype of SCK, and classified the other cell lines according to tumor cell differentiation (a poorly differentiated JCK, a moderately differentiated Cho-CK, and a well differentiated Choi-CK cells), both morphologically and immunocytologically. We further analyzed the genetic alterations of two tumor suppressor genes (p53 and FHIT) and the expression of Fas/FasL gene, well known CC-related receptor and its ligand, in these four CC cell lines. The deletion mutation of p53 was found in the sarcomatoid SCK cells. These cells expressed much less Fas/FasL mRNAs than did the other ordinary CC cells. We further characterize the gene expression pattern that is involved in the sarcomatous progression of CC, using cDNA microarrays that contained 18,688 genes. Comparison of the expression patterns between the sarcomatoid SCK cells and the differentiated Choi-CK cells enabled us to identify 260 genes and 247 genes that were significantly over-expressed and under-expressed, respectively. Northern blotting of the 14 randomly selected genes verified the microarray data, including the differential expressions of the LGALS1, TGFBI, CES1, LDHB, UCHL1, ASPH, VDAC1, VIL2, CCND2, S100P, CALB1, MAL2, GPX1, and ANXA8 mRNAs. Immunohistochemistry also revealed in part the differential expressions of these gene proteins. These results suggest that those genetic and gene expression alterations may be relevant to the sarcomatous change/EMT in CC cells. 相似文献
10.
Lee YM Kim HE Park CJ Lee AR Ahn HC Cho SJ Choi KH Choi BS Lee JH 《Journal of the American Chemical Society》2012,134(11):5276-5283
Z-DNA is produced in a long genomic DNA by Z-DNA binding proteins, through formation of two B-Z junctions with the extrusion of one base pair from each junction. To answer the question of how Z-DNA binding proteins induce B-Z transitions in CG-rich segments while maintaining the B-conformation of surrounding segments, we investigated the kinetics and thermodynamics of base-pair openings of a 13-bp DNA in complex with the Z-DNA binding protein, Zα(ADAR1). We also studied perturbations in the backbone of Zα(ADAR1) upon binding to DNA. Our study demonstrates the initial contact conformation as an intermediate structure during B-Z junction formation induced by Zα(ADAR1), in which the Zα(ADAR1) protein displays unique backbone conformational changes, but the 13-bp DNA duplex maintains the B-form helix. We also found the unique structural features of the 13-bp DNA duplex in the initial contact conformation: (i) instability of the AT-rich region II and (ii) longer lifetime for the opening state of the CG-rich region I. Our findings suggest a three-step mechanism of B-Z junction formation: (i) Zα(ADAR1) specifically interacts with a CG-rich DNA segment maintaining B-form helix via a unique conformation; (ii) the neighboring AT-rich region becomes very unstable, and the CG-rich DNA segment is easily converted to Z-DNA; and (iii) the AT-rich regions are base-paired again, and the B-Z junction structure is formed. 相似文献