• 한국결정성장학회지
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• 제16권1호
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• pp.8-11
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• 2006

The magnetic properties and crystal structures of $Sm_yGd_{2-y}Fe_{17-x}Si_x$ alloys ($0\leq\;x\leq2\;and\;y=0\~1.67$) have been investigated using x-ray diffraction and magnetic measurements. The $Sm_yGd_{2-y}Fe_{17-x}Si_x$ specimens were crystallized to the rhombohedral $Th_2Zn_{17}-structure$ with less than $5mol\%$ of impurities. The unit cells of the mixed rare-earth samples are smaller than those of $Sm_2Fe_{17}\;and\;Gd_2Fe_{17}.$ For example, the $T_c\;of\;SmGdFe_{17}\;(255^{\circ}C)$ is approximately 160 and $800^{\circ}C)$ higher than that of $Sm_2Fe_{17}\;and\;Gd_2Fe_{17},$ respectively. The $T_cs$ measured for $Sm_yGd_{2-y}Fe_{17-x}Si_x$ samples, 280 to $290^{\circ}C)$, are among the highest values observed for a $R_2Fe_{17-x}M_x$ intermetallic where M is a substituent other than cobalt.

• Progress in Superconductivity
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• 제10권2호
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• pp.128-132
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• 2009

Polycrystalline samples of $(Ru_{0.8}Nb_{0.2})Sr_2(Gd_{1.5-x}Nd_xCe_{0.5})Cu_2O_z$($ 0{\leq}x{\leq}1.25$) have been synthesized by a solid-state reaction route. The X-ray diffraction data revealed that the Nd solubility limit can be placed between x=0.5 and x=0.75. The superconducting transition temperature decreased with increasing Nd content, confirming that Nd entered the lattice. Room-temperature thermoelectric power measurements showed that all the samples are in the underdoped state and the partial substitution of Nd for Gd resulted in a decrease in the carrier density on the superconducting layers.

• Journal of Microbiology and Biotechnology
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• 제33권10호
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• pp.1337-1350
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• 2023

Caproic acid is a precursor substance for the synthesis of ethyl caproate, the main flavor substance of nongxiangxing baijiu liquor. In this study, Clostridium butyricum GD1-1, a strain with high caproic acid concentration (3.86 g/l), was isolated from the storage pit mud of nongxiangxing baijiu for sequencing and analysis. The strain's genome was 3,840,048 bp in length with 4,050 open reading frames. In addition, virulence factor annotation analysis showed C. butyricum GD1-1 to be safe at the genetic level. However, the annotation results using the Kyoto Encyclopedia of Genes and Genomes Automatic Annotation Server predicted a deficiency in the strain's synthesis of alanine, methionine, and biotin. These results were confirmed by essential nutrient factor validation experiments. Furthermore, the optimized medium conditions for caproic acid concentration by strain GD1-1 were (g/l): glucose 30, NaCl 5, yeast extract 10, peptone 10, beef paste 10, sodium acetate 11, L-cysteine 0.6, biotin 0.004, starch 2, and 2.0% ethanol. The optimized fermentation conditions for caproic acid production by C. butyricum GD1-1 on a single-factor basis were: 5% inoculum volume, 35℃, pH 7, and 90% loading volume. Under optimal conditions, the caproic acid concentration of strain GD1-1 reached 5.42 g/l, which was 1.40 times higher than the initial concentration. C. butyricum GD1-1 could be further used in caproic acid production, NXXB pit mud strengthening and maintenance, and artificial pit mud preparation.

• Progress in Superconductivity
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• 제13권2호
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• pp.127-132
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• 2011

Many research groups have been manufacturing coated conductor by various processes such as PLD, MOD, and MOCVD, but the methods with production cost suitable for wide and massive application of coated conductor did not develop yet. Spray pyrolysis method adopting ultrasonic atomization was tried as one of the possible option. GdBCO precursor films have been deposited on IBAD substrate by spray pyrolysis method at low temperature and converted to GdBCO by post heat treatment. Ultrasonic atomization was used to generate fine droplets from precursor solution of Gd, Ba, and Cu nitrate dissolved in water. Primary GdBCO films were deposited at $500^{\circ}C$ and oxygen partial pressure of 1 torr. After that, the films were converted at various temperatures and low oxygen partial pressures. C-Axis oriented films were obtained IBAD substrates at conversion temperature of around $870^{\circ}C$ and oxygen partial pressures of 500 mtorr ~ 1 torr in a vacuum. Thick c-axis epitaxial film with the thickness of 0.4 ~ 0.5 ${\mu}m$ was obtained on IBAD substrate. C-axis epitaxial GdBCO films were successfully prepared by ex-situ methods using nitrate precursors on IBAD metal substrate. Converted GdBCO films have very dense microstructures with good grain connectivity. EDS composition analysis of the film showed a number of Cu-rich phase in surface. The precursor solution having high copper concent with the composition of Gd : Ba : Cu = 1 : 2 : 4 showed the better grain connectivity and electrical conductivity.

• Investigative Magnetic Resonance Imaging
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• 제6권2호
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• pp.158-165
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• 2002

목적: 체내에 주입된 Gd-DTPA가 뇌의 확산강조 자기공명영상 신호강도 및 현성확산계수에 미치는 영향을 알아보았다. 대상 및 방법 : 성숙한 잡견 5마리에 대하여 동맥내 도관삽입에 의한 좌측 내경동맥 색전방법을 이용하여 초급성 뇌경색 동물모델을 만들었다. 색전 후 1시간째 확산강조영상을 시행하고, Gd-DTPA를 주입한 다음 다시 90분까지 11회의 추가 확산강조영상을 얻었다. 관심영역을 설정하여 측정한 초급성 뇌경색부위와 반대측 정상부위의 확산강조영상 신호강도 및 현성확산계수를 분석하였다. 결과: 뇌경색은 색전 후 1시간에 시행한 확산강조 자기공명영상에서 잡견 5마리 모두에서 발견되었다. 확산강조영상에서 초급성 뇌경색부위의 신호강도는 Gd-DTPA 주입 여부와 관계없이 시간이 경과함에 따라 증가하였으나, 관류가 유지된 정상부위의 신호강 도는 Gd-DTPA 주입 후 2분에 시행한 첫 검사에서 오히려 저하된 후, 시간경과에 따라 다시 증가하였다. 현성확산계수는 초급성 뇌경색부위에서 Gd-DTPA주입여부에 관계없이 시간 이 경과함에 따라 지속적으로 감소되었으나, 관류가 유지된 반대측 정상부위에서는 변화하지 않았다. 결론: 체내에 주입된 Gd-DTPA는 초급성 뇌경색부위 및 정상부위의 현성확산계수에 영향을 미치지 않으나, 정상부위에서는 조영제 주입 직후 초기의 자화율효과에 의해 확산강조영상의 신호 강도를 저하시켰다. 조영제 주입 후 시행한 확산강조영상 신호 강도의 정량적인 측정이 필요한 연구 혹은 임상 증례에 대하여는 현성확산계수를 측정함으로써 Gd-DTPA의 자화율효과에 의한 영향을 배제하여야 할 것이다.

• 한국축산식품학회지
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• 제35권3호
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• pp.322-329
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• 2015

This study investigated the effects of glucono-δ-lactone (GdL) addition on physicochemical and microbiological characteristics of fermented sausages during ripening and drying. Five batches of sausages were produced under ripening conditions: without GdL and with 0, 0.1, 0.25, 0.5 and 0.75% of GdL addition. Samples from each treatment were taken for physicochemical and microbiological analyses on the 0, 1, 3, 5, 7, 10, 15, 20 and 25th day of ripening. Chemical analysis showed a significant decrease in moisture content of sausages with increasing amounts of GdL added (p<0.05). The moisture contents decreased, whereas the fat, protein and ash contents increased throughout ripening (p<0.05). Increasing levels of GdL caused a decrease in the pH values (p<0.05), which can have an inhibitory effect against microflora. Water holding capacity content of samples decreased with increasing GdL concentration (p<0.05). The shear force values of fermented sausages showed the highest in T4 (p<0.05). During ripening, the shear force values of sausages were increased on the 25th day compared to day 0 (p<0.05). The higher GdL level produced lighter and more yellow sausages. The addition of 0.75% GdL was effective in controlling bacteria counts. Addition of GdL in sausages resulted in the physicochemical and microbiological attributes equal to or better than no addition of GdL without any harmful effect.

• 한국세라믹학회지
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• 제47권2호
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• pp.183-188
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• 2010

$Ce_{0.8}Gd_{0.2}O_{1.9}$(GDC20) powder was synthesized by milling of $CeO_2$ slurry and Gd oxalate precipitation. The mixture of $CeO_2$ powder and Gd precipitates calcined at $600^{\circ}C$ for 2 h showed the particle size distribution similar to that of $CeO_2$ powder, which had been milled during the synthesis process. Attrition milling of the calcined powder with an average particle size of $0.36\;{\mu}m$ for 2 h resulted in a decrease in the particle size to $0.24\;{\mu}m$. Although the milled powder consisted of small particles(<$1\;{\mu}m$), a small amount of fine platy $Gd_2O_3$ particles, which had been survived in the milling process, was observed. Sintering of the powder compacts for 4 h showed relative densities of 80.7% at $1300^{\circ}C$ and 97% at $1400^{\circ}C$, respectively. Densification was found to almost complete at $1500^{\circ}C$, resulting in a dense and homogeneous microstructure with a relative density of 99.5%.

• Applied Science and Convergence Technology
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• 제27권3호
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• pp.52-55
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• 2018

We reported a new method to enhance the photoluminescence (PL) properties of $Eu^{3+}$ ions doped $Gd_2Mo_4O_{15}$ phosphors via cation substitution. With the aid of conventional sol-gel method, a series of $Eu^{3+}$ ions doped $Gd_{2(1-x)}Y_{2x}Mo_4O_{15}$ phosphors were prepared. The prepared samples emitted red light when excited at 393 nm. Moreover, when part of the $Gd^{3+}$ ions was substituted by the $Y^{3+}$ ions, the PL emission intensity of the studied samples was enhanced and the optimal doping concentration for $Y^{3+}$ ions was 30 mol%. The calculated CIE coordinate (0.663,0.337) was situated in the red region. Furthermore, the thermal quenching behaviors of the synthesized $Eu^{3+}$ ions doped $Gd_{2(1-x)}Y_{2x}Mo_4O_{15}$ phosphors were studied. At last, we also packaged a red-emitting light-emitting diode device by integrating the obtained phosphors and a near-ultraviolet chip to verify the applications of the $Eu^{3+}$ ions doped $Gd_{2(1-x)}Y_{2x}Mo_4O_{15}$ phosphors for indoor lighting.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.70-75
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• 2000

We report results of a comparative study of the normal-state and superconducting properties in the GdBa$_2$(Cu$_{2.9}$Al$_{0.1}$)O$_z$ system with substitutions by Pr for the Gd and Ba sites. It is observed that, fur both Pr-doped systems, the superconducting transition temperature(T$_c$) decreases almost linearly with the Pr-content, but Pr at Ba sites results in a faster T$_c$ drop than that of Pr at Gd sites. The thermoelectric power measurements indicate that there is a strong correlation between the T$_c$ and the room temperature value of thermoelectric power. The experimental results are discussed in connection with existing models.

• Journal of Interdisciplinary Genomics
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• 제1권2호
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• pp.15-18
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• 2019

Gaucher disease (GD) is an autosomal recessive inborn error of metabolism resulting from a deficiency in ${\beta}$-glucocerebrosidase (GBA) activity that leads to the accumulation of glucocerebroside in macrophages in multiple organs, such as the bone marrow, liver, spleen, and brain. GD can be classified into three clinical types: type 1 (non-neuropathic form, OMIM #230800); type II (acute neuropathic form, OMIM #230900); and type III (chronic neuropathic form, OMIM #231000). Type III is the subacute form of neuropathic GD. The best available treatment for GD is long-term enzyme (imiglucerase) replacement therapy (ERT) performed every two weeks. This report describes the long-term clinical course of a patient with type III GD who was treated with ERT for 18 years.