• Journal of Magnetics
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• 제19권4호
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• pp.340-344
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• 2014

An effective process was employed for synthesizing anisotropic magnetic $SmCo_7$-type alloy flakes with high coercivity, which is highly desirable for many applications. The highest coercivity of 16.3 kOe corresponds to a typical flake thickness of 200 nm for the 3-h ball-milled sample. The anisotropy field was calculated by measuring the parallel and perpendicular directions to the easy magnetization direction of the powders. The anisotropy field decreased with the increase of the ball milling time, thus indicating that the decrease of coercivity was mainly caused by the reduction of the anisotropy field. Microstructure analysis indicated that the morphology, grain size, and anisotropy field of these samples have a great influence on the magnetic properties.

• E2M - 전기 전자와 첨단 소재
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• 제9권6호
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• pp.572-577
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• 1996

Alternating current and direct current of pure, ball milled, and $Al_{2}$O$_{3}$ added ZnO were investigated by means of complex impedance measurement and voltage-current source measurement unit. The electrical conductivity of A1$_{2}$O$_{3}$ added ZnO samples increases when the content of A1$_{2}$O$_{3}$ is used within 1 at% and decreases when it's used more than that. The increase and decrease of electrical conductivity seem to be the donor effect of $Al_{2}$O$_{3}$ and the increase of the number of ZnO grains, respectively. Impedance spectrum seems to be one semircicle. The size of semicircle increase with increasing the A1$_{2}$O$_{3}$ contents. The calculated dielectric constant(at 50.deg. C) were about 70-140 at the peak of the semicircle. The semicircles seem not to be the resistance of ZnO grain as compared to that of 10 for pure ZnO.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.305-307
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• 1997

Gd-doped $CeO_2$, ultrafine powders were synthesized by the glycine-nitrate process and then their sintering and electrical characteristics were analysed using the dilatometric and AC impedance measurements. In the dilatometric measurements green bodies from the synthesized powders after milling shrinked to about $1470^{\circ}C$ in appearance and then expanded thermally with the increase of the heating temperature, whereas those from the synthesized powders before milling continuously shrinked to the temperatures of $1600^{\circ}C$. It may be due to the change of the packing density of the synthesized powders by milling. In the AC impedance measurements, the electrical resistivity of the Gd-doped $CeO_2$ bodies from the as-milled powders, sintered at $1500^{\circ}C$ with the increase of the sintering time, showed the minimum value at the sintering time of 10h. The minimum total resistivity of the Gd-doped $CeO_2$ bodies sintered at $1500^{\circ}C$ for 10h seems to result from the lowest activation energy by the combination between the activation energies for the resistivities at the grain interior and grain boundary.

• Preventive Nutrition and Food Science
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• 제21권4호
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• pp.393-397
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• 2016

Whole grain wheat flour (WGWF) is the entire grain (bran, endosperm, and germ) milled to make flour. The WGWF of 31 Korean wheat (Triticum aestivum L.) cultivars were analyzed for the chemical compositions, and classified into groups by hierarchical cluster analysis (HCL). The average composition values showed a substantial variation among wheat varieties due to different wheat varieties. Wheat cv. Shinmichal1 (waxy wheat) had the highest ash, lipid, and total dietary fiber contents of 1.76, 3.14, and 15.49 g/100 g, respectively. Using HCL efficiently classified wheat cultivars into 7 clusters. Namhae, Sukang, Gobun, and Joeun contained higher protein values (12.88%) and dietary fiber (13.74 %). Regarding multi-trait crop breeding, the variation in chemical compositions found between the clusters might be attributed to wheat genotypes, which was an important factor in accumulating those chemicals in wheat grains. Thus, once wheat cultivars with agronomic characteristics were identified, those properties might be included in the breeding process to develop a new variety of wheat with the trait.

• 한국작물학회지
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• 제60권4호
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• pp.431-435
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• 2015

Rice (Oryza sativa L.) ratooning is the production of a second rice crop from the stubble left behind after the main crop harvest. The objectives of this study were to evaluate the effects of main-crop stubble height, irrigation and fertilization on ratoon grain yield. Main crop 'Jinbuol' rice cultivar was harvested to leave with 10, 20, 30, or 40 cm stubble height. When the main crop stubble was harvested with 10 cm height, ratoon rice grain yield was increased by 2,810 kg/ha. Irrigation on stubbles after main crop harvest did not affect the ratoon crop yield and rice quality. The results showed a large variation in the ratoon performance by fertilizer application methods. Top-dressed nitrogen fertilizer on the stubble after harvest caused increase in panicle production and higher maturity rate. However, there was no significant difference in protein content, amylose content of milled rice and cooked rice characters between plots managed with and without nitrogen fertilizer.

• 한국식품과학회지
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• 제12권3호
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• pp.182-184
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• 1980

벼를 현미(玄米)와 쌀로 가공(加工)할 때 유의(留意)해야 할 가공(加工) 특성(特性)을 구명(究明)하고저 11개(個) 품종(品種)을 대상(對象)으로 하여 시험(試驗)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 제현시(製玄時) 사용(使用)되는 사목(飾目)의 크기에 따른 제현률차(製玄率差)는 현미립(玄米粒)의 넓이 및 두께와 부(負)의 상관(相關)이 있었다. 2. 현백(玄白) 과정(過程)에서 생기는 쇄미률(碎米率)은 현미(玄米) 입장(粒長)과 상관(相關)이 있었다. 3. 공시(供試) 품종중(品種中) 협형(狹形)과 장립종(長粒種)에 해당(該當)되는 것은 없었다. 4. 쌀의 백도(白度)는 동일(同一)한 수준(氷準)의 도정도(搗精度)에서 $12{\sim}32M$의 범위에 폭(幅)넓게 분포(分布)되어 있었다.

• 농업과학연구
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• 제37권2호
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• pp.177-189
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• 2010

These studies were conducted to analysis for weather reaction on the growth and yield component according to meterological elements used Vector Autoregressive Regression(VAR) Model at Daejeon, Hongseong, Geumsan, Nonsan, and Yesan to core of center to Chungnam area in Rice. Reaction of cultivars according to change of meterological elements for growth and yield component effected on heading time in Gancheokbyeo and Mananbyeo, grain number of a spike in Gancheokbyeo, ratio of ripeness in Gancheokbyeo and Geumobyeo 1, amount of milled rice in Geurubyeo and Ansanbyeo, and 1,000 grains weight in Gancheokbyeo, Dasanbyeo, and Hwajinbyeo. An effect on the growth and yield components of meterological elements were influenced by heading date, 1,000 grain weight and ratio of repening as sunshine hours. The cultivars in sensitive reaction for change of weather condition were classified to 14 varieties including Gerubyeo et al., insensitive cultivars were classified to 66 varieties including Gyehwabyeo et. al.

• Journal of Magnetics
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• 제21권2호
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• pp.192-196
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• 2016

The Fe-Si-B-Nb-Cu alloys containing Ca and Al were rapidly solidified to thin ribbons by melt-spinning. The ribbons were ball-milled to make powders, and then mixed with 1 wt.% water glass and 1.5 wt.% lubricant. The mixed powders were burn-off, and then compacted to form toroidal-shaped cores, which were heat treated to crystallize the nano-grain structure and to remove residual stress of material. The characteristics of the powder cores were analyzed using a differential scanning calorimetry (DSC) and a B-H meter. The microstructures were observed using transmission electron microscope (TEM). The optimized soft magnetic properties (${\mu}_i$ and $P_{cv}$) of the powder cores were obtained from the Ca and Al containing alloys after annealing at $530^{\circ}C$ for 1 h. The core loss of Fe-Si-B-Nb-Cu-based powder cores was reduced by the addition of Ca element, and the initial permeability increased due to the addition of Al element.

• Journal of Plant Biotechnology
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• 제40권2호
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• pp.88-101
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• 2013

Eating quality of rice attracts more and more attention from rice-eating consumers in the recent years. Thus, improvement of eating quality of cooked rice has become one of the most important breeding goals in japonica rice. Here, the generation of transgenic japonica rice with improved eating quality and grain yield are reported. Overexpression of OsSbe1 gene encoding rice starch branching enzyme 1 was driven by 35S promoter. Eleven independent homozygous $T_3$ transgenic lines were characterized and had shown higher palatability (71.2 ~ 72.6) than wild type Gopum (70.4). Moreover, transgenic rice lines showed an increase in 1000-grain weight and number of spikelets per panicle compared with the wild type. The yield of milled rice was 562.8 ~ 596.7 kg/10a in eight $T_3$ lines, but 542.1 kg/10a in wild type. Gene expression analyses in mRNA transcription and enzyme activity levels suggest that improved eating quality is due to the up-regulation of OsSbe1 gene.

• 대한금속재료학회지
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• 제50권1호
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• pp.39-44
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• 2012

Nanopowders of TiCo were synthesized from Ti and Co by high energy ball milling. Highly dense nanostructured TiCo compounds were consolidated at low temperature by pulsed current activated sintering within 3 minutes from the mechanical synthesis of the powders (TiCo) and horizontal milled Ti+Co powders under 100 Mpa pressure. This process allows very quick densification to near theoretical density and prohibits grain growth in nanostructured materials. The grain sizes of the TiCo compounds were calculated. Finally, the average hardness values of the nanostructured TiCo compounds were investigated.