• Title/Summary/Keyword: $U_3 O_8$

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Cytoprotective Effect on Oxidative Stress and Inhibitory Effect on Cellular Aging of Terminalia chebula and Uncaria sinensis

  • Na, Min-Kyun;Hong, Nam-Doo;Kamiryo Yuko;Senoo, Yu-Ichiro;Yokoo Seiichi;Ito Shinobu;Miwa Nobuhiko
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.201.3-201.3
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    • 2003
  • The ethanol extract from the fruit of Terminalia chebula (Combretaceae) and the hook of Uncaria sinensis (Rubiaceae) exhibited significant inhibitory activity on oxidative stress and the age-dependent shortening of the telomeric DNA length. In the peroxidation model using t-BuOOH, human epidermal keratinocytes-neonatal foreskin (HEK-N/F) cells were treated with the T. chebula and U. sinensis extracts. The results showed a notable enhancing effect on the cell viability of 60.5 ${\pm}$ 3.8 and 65.0 ${\pm}$ 3.0%, respectively, by 50 $\mu\textrm{g}$/ml of the extracts. (omitted)

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Spark plasma sintering of UO2 fuel composite with Gd2O3 integral fuel burnable absorber

  • Papynov, E.K.;Shichalin, O.O.;Belov, A.A.;Portnyagin, A.S.;Buravlev, I.Yu;Mayorov, V.Yu;Sukhorada, A.E.;Gridasova, E.A.;Nomerovskiy, A.D.;Glavinskaya, V.O.;Tananaev, I.G.;Sergienko, V.I.
    • Nuclear Engineering and Technology
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    • v.52 no.8
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    • pp.1756-1763
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    • 2020
  • The paper studies spark plasma sintering (SPS) of industrially used UO2-based fuel containing integral fuel burnable absorber (IFBA) of neutrons Gd2O3. Densification dynamics of pristine UO2 powder and the one added with 2 and 8 wt% of Gd2O3 under ultrasonication in liquid has been studied under SPS conditions at 1050, 1250, and 1450 ℃. Effect of sintering temperature on phase composition as well as on O/U stoichiometry has been investigated for UO2 SPS ceramics. Sintering of uranium dioxide added with Gd2O3 yields solid solution (U,Gd)O2, which is isostructural to UO2. SEM with EDX and metallography were implemented to analyze the microstructure of the obtained UO2 ceramics and composite UO2-Gd2O3 one, particularly, open porosity, defects, and Gd2O3 distribution were studied. Microhardness, compressive strength and density were shown to reduce after addition of Gd2O3. Obtained results prove the hypothesis on formation of stable pores in the system of UO2-Gd2O3 due to Kirkendall effect that reduces sintering efficiency. The paper expands fundamental knowledge on pros and cons of fuel fabrication with IFBA using SPS technology.

Transglycosylation Reaction on Cellobiose by Dextansucrase of Leuconostoc mesenteroides B512FMC/6HG8 (Leuconostoc mesenteroides B512FMC/6HG8가 생산하는 Dextransucrase에 의한 Cellobiose의 당전이반응)

  • 강현록;양지영;이현규
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.5
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    • pp.802-806
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    • 2000
  • The transglycosylation reaction by dextansucrase from Leuconostoc mesenteroides B512FMC/6HG8 was investigate with cellobiose as an acceptor molecule and sucrose as a donor. he optimal conditions of transglycosylation on cellobiose were found that the ration of sucrose to cellobiose was 3:1, the amount of enzyme was 2U/mL, the ionic strength of buffer was 25 mM, pH was 5.0 and reaction temperature was $25^{\circ}C$. also, acceptor products of cellobiose by transglycosylation were a series of oligosaccharides showing the degree of plymenzation of 6.

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EFFECTS OF AMMONIATED RICE STRAW FEEDING ON MICROBES AND THEIR FERMENTATION END-PRODUCTS IN THE RUMEN AND CAECUM OF SHEEP

  • Cann, I.K.O.;Kobayashi, Y.;Wakita, M.;Hoshino, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.1
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    • pp.67-72
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    • 1993
  • Three sheep fitted with cannulas in the rumen and the caecum were used in a $3{\times}3$ Latin square design to study the changes in ruminal and caecal microbial populations and their metabolite composition with ammoniated rice straw feeding. The 3 diets contained either 80% untreated rice straw (UTS) or ammoniated rice straw (ATS) and 20% formula feed. These were a control diet (C), a urea supplemented diet (U) containing urea at 1.1% and an ammoniated rice straw diet (AT). Data were analyzed by analysis of variance and means separated by the Student Neumann Kuel's multiple comparison. AT feeding increased ruminal bacterial counts, in particular cellulolytic bacterial counts (p < 0.05) which were 1.8, 2.4 and 7.0 (${\times}10^6/ml$ ruminal fluid) for C, U and AT, respectively. There was an increasing tendency (p < 0.10) in ruminal fungal population with U; values were 2.0, 5.2, 3.1 (${\times}10^3/ml$ ruminal fluid) for C, U and AT, respectively. Ruminal protozoa counts were not significantly (p > 0.05) altered with diets. Caecal total viable bacterial count with AT was about thrice the value with C. Total VFA concentration in the rumen was significantly increased (p < 0.025) (7.7 mmol/dl for C and 8.2 mmol/dl for AT) and correspondingly, pH lowered when AT was fed. Sheep on AT tended to produce less acetate and more butyrate in the rumen without significance (p > 0.05). Similar to the rumen, total VFA concentrations of 4.4, 3.8 and 5.2 mmol/dl were detected, respectively, for C, U and AT. Caecal ammonia-nitrogen concentrations were about six-fold of that in the rumen, though there were no differences (p > 0.05) among treatments.

Study of HubWA Protein Folding Reaction by Measuring the Stability of Folding Intermediate (중간단계의 구조적 안정성을 통한 HubWA 단백질의 접힘(folding) 반응 탐색)

  • Soon-Ho Park
    • Journal of the Korean Chemical Society
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    • v.67 no.2
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    • pp.81-88
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    • 2023
  • The contribution of hydrophobic residues to the protein folding reaction was studied by using HubWA variant proteins with I and L to V mutation. Folding kinetics of all V variant proteins was observed to be satisfied by a three-state on-pathway mechanism, U ⇌ I ⇌ N, where U, I, and N represent unfolded, intermediate, and native state, respectively. Three-state folding reaction was quantitatively analyzed and the free energy of folding of each elementary reactions and overall folding reaction, ΔGoUI, ΔGoIN, and ΔGoUN, were obtained. From the ratio of free energy difference between the variant protein and HubWA, ΔΔGoUI/ΔΔGoUN (ΔΔGoUI = ΔGoUI (variant protein) - ΔGoUI (HubWA) and ΔΔGoUN = ΔGoUN (variant protein) - ΔGoUN(HubWA)), the contribution of hydrophobic residues to HubWA folding was analyzed. The residues which are located in the hydrophobic core between α-helix and β-sheet, I3, I13, L15, I30, L43, I61 and L67, showed ΔΔGoUI/ΔΔGoUN value of ~0.5 when each of these residues was mutated to V, indicating that these residues form relatively solid hydrophobic core in the intermediate state. Residues located at the end of secondary structures and loop, I23, L69 and I36 showed ΔΔGoUI/ΔΔGoUN value below 0.4 when each of these residues was mutated to V, indicating that the region containing these residues are loosely formed in the intermediate state. V17A, L50V and L56V showed fairly high ΔΔGoUI/ΔΔGoUN value of ~0.8. Since L50 and L56 are located in the region containing long loop (residue 46 to 62), it is suggested that the high ΔΔGoUI/ΔΔGoUN value of these residues prevents the formation of aggregate at the early stage of folding reaction.

A Basic Study on Spherical UO2 Kernel Preparation Using the Sol-Gel Method (Sol-Gel법을 이용한 구형 UO2 Kernel 제조에 관한 기초연구)

  • Kim, Yeon-Ku;Jeong, Kyung-Chai;Oh, Seung-Chul;Cho, Moon-Sung;Na, Sang-Ho;Lee, Young-Woo;Chang, Jong-Wha
    • Journal of the Korean Ceramic Society
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    • v.42 no.9 s.280
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    • pp.618-623
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    • 2005
  • HTGR (High Temperature Gas-Cooled Reactor) is highlighted to next generation power plant for producing the clean hydrogen gas. In this study, the spherical $UO_2$ kernel via $UO_3$ gel particles was prepared by the sol-gel process. Raw material of slightly Acid Deficient Uranyl Nitrate (ADUN) solution, which has pH = 1.10 and $[NO_3]/[U]$ mole ratio = 1.93, was obtained from dissolution of $U_3O_8$ powder with conc.-$HNO_3$. The surface of these spherical $UO_3$ gel particles, which was prepared from the broth solution, consisted of 1 M-uranium, 1 M-HMTA, and urea, were covered with the fine crystallite aggregates, and these particles were so hard that crushed well. But the other $UO_3$ gel particles prepared with the broth solution, consisted of 2 M-uranium, 2 M-HMTA, and urea, have soft surface characteristics and an amorphous phase. This type of $UO_3$ gel particles is some chance of doing possibility of high density from the compaction. The amorphous $UO_3$ gel particles was converted to $U_3O_8$ and then $UO_2$ by calcination at $600^{\circ}C\;in\;4\%\;-\;H_2\;+\;N2$ atmosphere.

Study on Dai Meridian(帶脈) and Meridian Points(經穴) of Joining with Circulation of Dai Meridian through Literatures of Every Generation (대맥(帶脈) 및 그 유주상(流注上) 회합(會合)하는 경혈(經穴)에 대한 문헌적(文獻的) 고찰(考察))

  • Yang Seung-Joung;Jin Cheon-Sik;Cho Myung-Rae
    • Korean Journal of Acupuncture
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    • v.18 no.1
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    • pp.105-116
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    • 2001
  • We examined and referred to some literatures on the meaning, Dai meridian and Meridian points of joining with circulation of Dai meridian through literatures of every generation. And then we came to get a few conclusions as follows. 1. Dai meridian starts below the hypochondriac region. Running obliquely downward, it runs transversely around the waist like a belt. Its function is to bind up all the meridians to circulate in a proper way. 2. The coalescent points of dai meridian are $D\grave{a}im\grave{a}i$(帶脈), $W\check{u}sh\bar{u}$(五樞) and $W\acute{e}id\grave{a}o$(維道). 3. Location of $D\grave{a}im\grave{a}i$(帶脈) is on the lateral side of the abdomen, 1.8 cun below $Zh\bar{a}ngm\grave{e}n$(章門), at the crossing point of vertical line through the free end of the 11th rib and a horizontal line through the umbilicus. Location of $W\check{u}sh\bar{u}$(五樞) is on the lateral side of the abdomen, anterior to the anterosuperior iliac spine, 3 cun below the level of the umbilicus. Location of $W\acute{e}id\grave{a}o$(維道) is on the lateral side of the abdomen, anterior and inferior to the anterosuperior iliac spine, 0.5 cun anterior and inferior to $W\check{u}sh\bar{u}$(五樞). 4. Indication of $D\grave{a}im\grave{a}i$(帶脈) is irregular menstruation, leukorrhea with reddish discharge, hernia, pain in the lumbar and hypochondriac region. Indication of $W\check{u}sh\bar{u}$(五樞) is prolapse of the uterus, leukorrhea with reddish discharge, irregular menstruation, hernia, pain in the lower abdomen, constipation and lumbosacral pain. Indication of $W\acute{e}id\grave{a}o$(維道) is edema, pain in the side of the lower abdomen, prolapse of the uterus, hernia and morbid leukorrhea. 5. The Dai meridian binds all meridians, produces pregnancy, grasps lumbar and abdomen region and controls leukorrhea. 6. Diseases of the Dai meridian manifested as distention and fullness in the lumbar region and abdomen, leukorrhea with reddish discharge, pain the navel, lumbar and spinal regions, flaccidity and hypoactivity of the lower limbs, etc.

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Increased Production of an Alkaline Protease from Bacillus clausii I-52 by Chromosomal Integration (Bacillus clausii I-52의 Chromosomal Integration에 의한 Alkaline Protease의 생산성 향상)

  • Joo, Han-Seung;Park, Dong-Chul;Choi, Jang-Won
    • Journal of agriculture & life science
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    • v.46 no.1
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    • pp.163-176
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    • 2012
  • TTo increase productivity of a strong extracellular alkaline protease (BCAP), stable strains of Bacillus clausii I-52 carrying another copy of BCAP gene in the chromosome were developed. Integrative vector, pHPS9-fuBCAP carrying BCAP promoter, ribosome binding site, signal sequence and active protease gene was constructed and transferred into B. clausii I-52, and integration of the constructed plasmid into chromosome was identified by PCR. An investigation was carried out on BCAP production by B. clausii I-52 and transformant C5 showing the highest relative activity of alkaline protease using submerged fermentation. Maximum enzyme activity was produced when cells were grown under the submerged fermentation conditions at $37^{\circ}C$ for 48 h with an aeration rate of 1 vvm and agitation rate of 650 rpm in a optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_47H_2O$ 0.01%, $FeSO_47H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). A protease yield of approximately 134,670U/ml was achieved using an optimized media, which show an increase of approximately 1.6-fold compared to that of non-transformant (83,960 U/ml). When the stability of transformant C5 was examined, the integrated plasmid pHPS9-fuBCAP was detected in the transformant after cultivation for 8 days, suggesting that it maintained stably in the chromosomal DNA of transformant C5.

The Effects of Sample Disturbance on Undrained Properties of Yangsan Clay (양산점토의 비배수 특성에 대한 시료교란의 효과)

  • 김길수;임형덕;이우진
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03b
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    • pp.639-646
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    • 2000
  • It is important to estimate the mechanical properties of clay since it is directly related to the design and the construction of geotechnical structures. Site exploration, which is composed of boring, sampling, in-situ, or laboratory tests, is preformed to estimate the mechanical properties. However, mechanical properties of clay measured from laboratory test may be different from in-situ properties due to disturbances occurred during sampling, transportation, storage, and trimming. In this study, the degree of disturbance according to sampling method was estimated with the test results of CK/sub o/U triaxial compression test on Yangsan clay. The soil samples were obtained by three types of sampling method, j.e., 76mm-tube sampler, 76mm-piston sampler, and block sampler. In order to evaluate the quality of samples, volumetric strain, undrained shear strength, secant Young's modulus, and pore pressure coefficient at peak measured from each sample were compared with one another. From the test results, it was observed that mechanical properties of the block and piston samples were more reliable than those of tube samples. But it was observed that the water content of piston was similar to that of tube samples at given depths while the water content of block samples was 14.3∼15.8% smaller than that of piston and tube samples. In addition to the evaluation of the quality of samples, relationship between c/sub u// σ/sub vc/'and OCR was established from the results of the CK/sub o/U triaxial compression tests, which were carried out using SHANSEP method. And also undrained shear strength was analyzed using the in-situ test data such as Cone Penetration Test(CPT), Dilatometer Test(DMT), and Field Vane Test(FVT) and was compared with that evaluated from CK/sub o/U triaxial compression test.

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