• Journal of Powder Materials
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• v.11 no.2
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• pp.149-157
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• 2004

High temperature deformation behavior of activated sintered W powder compacts was investigated. The compression tests were carried out in the temperature range between 900 and 110$0^{\circ}C$ at the strain rate of $10^{-3}s^{-1}$. The sintered specimens of Ni-doped submicron W powder compacts showed decrease in W grain size with increasing the Ni content. As the result, the flow stress was significantly increased with increasing the Ni content. We obtained Ni-activated sintered W compacts with the relative density of 94 $\pm$ l％and the average grain size of less than 5${\mu}{\textrm}{m}$. A moderate true strain up to 0.60 was obtained without fracture even at 110$0^{\circ}C$ with the strain rate of $10^{-3}s^{-1}$ for the activated W compact despite adding the 1.0 wt％Ni to submicron W powder.

• Plant Resources
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• v.7 no.1
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• pp.36-38
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• 2004

Bacterial grain rot of rice caused by Burkholderia glumae was examined between weather condition and disease incidence. From 1998 to 2000, average disease incidence was 3.0 ％ without difference in survey regions. However, it was related closely to amount of rainfall that disease incidence higher in 1998 and 2000 to 3.0 ％ and 3.6 ％ respectively than 2.3 in 1999 relatively small volum of rainfall season.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.75-90
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• 2003

A total of 192 Korean landraces were investigated for the comparison of each other as useful germplasm to organic farming and examined correlation between quantitative traits. Almost Korean landraces were classified into medium-heading variety and average days from seeding to heading was 111.1 days. Plant height and culm length were longer about 20∼40cm than general Japonica cultivar. Average width of leaf blade and average length of panicle were 1.3cm and 22.4cm, respectively, Average number of panicles per plant was 10.0 and almost varieties showed low tilling habit. Average length/width ratio of brown rice was 1.7 and several varieties were long grain type and average 1,000 grain weight was 21.6g. In correlation coefficient among quantitative traits, positive significant correlations were observed between culm length and leaf width, days from seeding to heading, but negative correlations were observed between days from seeding to heading and 1000 grain weight. 27.1% of Korean landraces showed weak and lodging degree in culm strength and 3.6% of total varieties showed purple margin on leaf blade and leaf sheath. In leaf blade angle and flag leaf angle, erect type was 46.9% and 10.9%, respectively. 24.0% of total varieties showed the slow and late degree of leaf senescence. The rate of awned type, waxy type and brown seed coat were 74.5%, 20.3% and 4.2%, respectively. The color of stigma, spikelet, apiculus and awn showed diverse color such as white, brown, red and purple.

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.1-4
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• 2009

This study was carried out to evaluate ecological growth characteristics of forty castor bean collections for biodiesel utilization. The emergence date and it's rate of collections was 15-16 days and 82.5%, respectively. It took 63-68 days from emergence to flowering. Stem length was ranged from 173 to 251 cm with an average 211.8 cm. The average stem diameter was 24.2 cm, and showed the high occurrence as 52.5% at the 20.4-24.9 cm. The node number was widely distributed as 13-22 and the average node number was 18.9. The seed numbers were widely distributed as 7-33ea, and the average liter weight of seed was 502.9 g of which minimum weight was 432.3 g and maximum weight was 572.5 g, and the gap between maximum and minimum was 140.2 g. It showed high difference. The 100 grain weight was distributed as 20.3 g-38.3 g which showed high differences between small grain and large grain collections. The seed numbers per plant were varied as 72 at the minimum and 1,011 at the maximum number, and average seed number was 465.2. The total yields of seed per plant were varied as 20 g-266.2 g, and the average yields were 128.1 g.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1575-1579
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• 2007

The glucose tolerance and pancreatic insulin secretion response to glucose in sheep fed on germinated sorghum grain were determined using an intravenous glucose load. Twelve male Thin Tail sheep (an Indonesian native sheep, 12 months old and 14.8 kg average body weight) were divided randomly into sorghum grain-based (S), germinated sorghum grain-based (G) and maize grain-based (C) diets. Sheep were maintained at the same daily intake levels of metabolizable energy and crude protein in the diets throughout the experimental period. After two months of the experimental conditions, each diet group was subjected to an intravenous glucose load experiment in which five doses of glucose (0, 10, 20, 40 and 80 mg/kg BW) were injected to estimate the rate of glucose removal from blood and the pancreatic insulin secretion response. For each sheep and each glucose load dose, the incremental blood serum glucose and insulin concentrations above pre-injection concentration were calculated as serum glucose and insulin response areas. At all glucose doses, sheep fed on S diet had a greater (p<0.05) glucose response area compared to those of sheep fed on G and C diets. Likewise at all glucose doses, the insulin response area was smaller (p<0.05) in sheep fed on S diet than in sheep fed on G and C diets. The glucose and insulin response areas in sheep fed on G and C diets differed slightly. It was concluded that the portion of maize grain in the ruminant ration could be substituted by germinated sorghum grain.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.629-632
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• 2004

The objectives of this study were to determine the effects of substituting bread by-product (BBP) for barley grain in high concentrate fattening diets for kids on nutrient intake, growth performance, and nutrient digestibility. Twenty-eight Baladi kids (body weight=17.1${\pm}$1.0 kg) were assigned randomly to 4 experimental finishing diets (7 kids/treatment) in a completely randomized design for 70 days. The control (CON) diet contained 20, 60, 11, 7 and 2% (DM basis) alfalfa hay, barley grain, soybean meal, corn grain, and mineral and vitamin mix, respectively. Bread by-product substituted barley grain by 10, 20 and 30% of the diet DM in the LBBP, MBBP, and HBBP diets, respectively. Dry matter intakes for the CON, LBBP and MBBP diets were similar (p>0.05; avg.=592 g/day), however, kids fed the HBBP diet had a lower (p<0.05) DM intake (451 g/day). Organic matter and CP intakes showed similar patterns to that observed for DM. Dietary treatments did not affect (p>0.05) average daily gain for kids fed the CON, LBBP and MBBP diets (avg.=150 g/day). Final body weights for kids fed the CON, LBBP and MBBP diets (avg. 27.1 kg) were greater (p<0.05) than for kids fed the HBBP diet (23.7 kg). Feed to gain ratio was greater for the CON, LBBP and MBBP diets (avg. 3.9) compared with the HBBP diet (5.0). No significant (p>0.05) effect of the dietary treatment was observed for DM, OM and NDF digestibility. Substituting BBP for barley grain up to 20% of the diet DM did not affect nutrient intake, growth performance and nutrient digestibility of kids and resulted in a decrease in feed cost.

• Journal of Powder Materials
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• v.25 no.2
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• pp.104-108
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• 2018

Grain-growth behavior in the $95Na_{1/2}Bi_{1/2}TiO_3-5BaTiO_3$ (mole fraction, NBT-5BT) system has been investigated with the addition of $Na_2CO_3$. When $Na_2CO_3$ is added to NBT-5BT, the growth rate is higher than desired and grains are already impinging each other during the initial stage of sintering. The grain size decreases as the sintering temperature increases. With the addition of $Na_2CO_3$, a liquid phase infiltrates the interfaces between grains during sintering. The interface structure can be changed to be more faceted and the interface migration rate can increase due to fast material transport through the liquid phase. As the sintering temperature increases, the impingement of abnormal grains increases because the number of abnormal grains increases. Therefore, the average grain size of abnormal grains can be decreased as the temperature increases. The phenomenon can provide evidence that grain coarsening in NBT-5BT with addition of $Na_2CO_3$ is governed by the growth of facet planes, which would occur via mixed control.

• Korean Journal of Materials Research
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• v.16 no.6
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• pp.360-366
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• 2006

A series of ZnO thin films were grown by radio-frequency (RF) magnetron sputtering with various RF powers on $SiO_2/Si$(100) substrates at $500^{\circ}C$. Thicknesses of the investigated ZnO films were fixed to about 250nm by changing the growth time based on the changes of growth rates with RF powers. All the ZnO thin films were grown with <0001> preferred orientation. Average grain sizes of about 250nm-thick ZnO films evaluated by FE-SEM, AFM, and TEM were increased by decreasing the RF power. Structural properties addressed by FWHM values of XRD (0002) omega rocking curves and their intensities were better for the smaller grain sized ZnO films grown with high RF powers, which implies small values of tilt for smaller grain sized ZnO films. However, optical properties addressed by intensities of band edge emissions from room temperature and low temperature photoluminescence were better for the larger grain sized ZnO films with low RF power, which implies grain boundaries acted as nonradiation recombination centers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.14-25
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• 2006

Response of grain yield and milled-rice protein content to nitrogen (N) rates at various growth stages is critical for quantifying real-time and real-amount of applied N requirement for target grain yield and protein content. An experiment including 10 N rate treatments at transplanting, tillering and panicle initiation stages with four rice cultivars in 2003, 6 N treatments with two rice cultivars in 2004 and 2005 was conducted. Increase of N rates at PIS significantly increased both grain yield and milled-rice protein content but increase of N rates at tillering stage significantly increased grain yield but not milledrice protein content. Therefore, high grain yield and low milled-rice protein content would be difficult to obtain only by adjusting N rates at PIS. Internal N use efficiency (INUE) was 60.5 kg grain/kg N accumulation on an average over N treatments, cultivars, and experimental years, showing considerable reduction especially at high shoot N accumulation in the experimental year of low sunshine duration. Milled-rice protein content tended to increase almost linearly with increasing shoot N accumulation, but it revealed big variation even at the same shoot N accumulation at harvest. Milled-rice protein content decreased with increasing INUE. N accumulation in the milled rice increased at an almost constant proportion of 45.5 percent of the shoot N accumulated at harvest, showing slight decresing proportion with the increasing shoot N accumulation.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.38.1-38.1
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• 2021

Dust polarization depends on the physical and mechanical properties of dust, as well as the properties of local environments. To understand how dust polarization varies with grain mechanical properties and the local environment, in this paper, we model the wavelength-dependence polarization of starlight and polarized dust emission by aligned grains by simultaneously taking into account grain alignment and rotational disruption by radiative torques (RATs). We explore a wide range of the local radiation field and grain mechanical properties characterized by tensile strength. We find that the maximum polarization and the peak wavelength shift to shorter wavelengths as the radiation strength U increases due to the enhanced alignment of small grains. Grain rotational disruption by RATs tends to decrease the optical-near infrared polarization but increases the ultraviolet polarization of starlight due to the conversion of large grains into smaller ones. In particular, we find that the submillimeter (submm) polarization degree at 850㎛(P850) does not increase monotonically with the radiation strength or grain temperature (Td), but it depends on the tensile strength of grain materials. Our physical model of dust polarization can be tested with observations toward star-forming regions or molecular clouds irradiated by a nearby star, which have higher radiation intensity than the average interstellar radiation field. Finally, we compare our predictions of the P850-Td relationship with Planck data and find that the observed decrease of P850 with Td can be explained when grain disruption by RATs is accounted for, suggesting that interstellar grains unlikely to have a compact structure but perhaps a composite one. The variation of the submm polarization with U (or Td)can provide a valuable constraint on the internal structures of cosmic dust