• Journal of Powder Materials
• /
• v.11 no.2
• /
• pp.165-170
• /
• 2004

Growth behavior of two different types of grains, faceted and rounded, in a liquid matrix has been studied in the (75WC-25TiCN)-30Co system. Powder samples were sintered above the eutectic temperature for various times under a carbon saturated condition. (Ti,W)(C,N) grains with a rounded shape and WC grains with a faceted shape coexisted in the same Co based liquid. With increasing sintering time, the average size of (Ti.W)(C,N) grains increased continuously and very large WC grains appeared. The growth of rounded (Ti,W)(C,N) grains followed a cubic law, r^3-r^3_0$=kt, where r is the average size of the grains, $r_0$ the initial average size, k the proportionality constant and t the sintering time. indicating a diffusion-controlled growth. On the other hand, the growth of the faceted WC grains resulted in a bimodal grain size distribution, showing an abnormal grain growth. These observations show that the growth behavior of different types of grains is governed by their shape, faceted or rounded, even in the same liquid matrix.

• Asian-Australasian Journal of Animal Sciences
• /
• v.7 no.4
• /
• pp.517-522
• /
• 1994

Three experiments were carried out to evaluate the fermentation process and subsequent nutritional quality of silage made from dried and fresh barley straw with and without the addition of wet brewers' grains. The treatments were: 1 kg of dried straw with 600 g of water but no wet brewers' grains (I - 0) as a control, and the same straw mixed with 2 kg (I - 2), 3 kg (I - 3), 4 kg (I - 4), or 5 kg (I - 5) of wet brewers' grains as treatments in Experiment I; and 2 kg of fresh straw without wet brewers' grains (II - 0) as a control, and the same fresh straw mixed with 2 kg (II - 1), 4 kg (II - 2), 6 kg (II - 3), or 8 kg (II - 4) of wet brewers' grains as treatments in Experiment II. Each material prepared was ensiled in 5 L (vinyl) bag silos, and the silos placed in a chamber of $21^{\circ}C$ for 10 (Exp. I) or 7 (Exp. II) months. The fermentation quality and nutritive value of the barley straw silages produced were markedly improved by mixing them with wet brewers' grains. Increasing levels of wet brewers' grains caused on increase in fermentation quality. The in vitro dry matter digestibility of silages was also increased by adding wet brewers' grains. Two semi scale pilot silages, experiment III, prepared from dried and fresh barley straw mixed with wet brewers' grains were fed to wether sheep. These silages, which contained 50% barley straw and 50% wet brewers' grains by dry weight, were moderate apparent digestibility and supplied of about 50% TDN and DCP.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.48 no.2
• /
• pp.120-126
• /
• 2003

Four different rice varieties, Sindongjinbyeo, Dongjin #1, Saegyehwabyeo, and Iksan 467, were transplanted under three different nitrogen levels and two different seedling numbers per hill to obtain basic information on panicle traits under different cultural conditions and to propose the ideal panicle structure in Japonica rice. Sindongjinbyeo and Iksan 467 were characterized by more primary rachis branches (PRBs) per panicle and more grains on PRB than other cultivars. The two varieties also had fewer secondary rachis branches (SRBs) per PRB and fewer grains on SRB per PRB. These characteristics, consequently, resulted in higher ripened grain rate, contrary to that of Dongjin #1 and Saegyehwabyeo. In the correlation coefficient analysis, PRB number per panicle and grain number on PRB per panicle were positively correlated with ripened grain rate, while SRB number per panicle, number of grains on SRB per panicle, SRB number per PRB, number of grains on SRB per PRB and grain number per panicle were negatively correlated with ripened grain rate. Therefore, the number of grains on PRB per panicle, SRB number per PRB and the number of grains on SRB per PRB were the appropriate criteria for determining and achieving higher ripened grain rate in rice. High ripened grain rate over 90% was obtainable with over 12.5 PRBs per panicle and 63 grains on PRB per panicle, and with under 1.7 SRBs per PRB, 5 grains on SRB per PRB, 130 grains per panicle, and 14 panicles per hill. The study recommended that for over 90% high ripened grain rate, the critical limiting factors should be under 2 SRBs per PRB, 6 grains per PRB, and 130 grains per panicle, irrespective of the PRB number per panicle and the number of grains on PRB.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1992.10a
• /
• pp.55-60
• /
• 1992

Hydraulically filled ground is formed by the settling of soil grains from the mixture of soil grains and water. It was generally known that the settling speed of the soil grains in governed by Stokes low. In the case of clayed dredged material, the shape of soil grains is not round, the surface of the soil grains is relatively large compared to the weight of soil grains and inter-grain ionic force is relatively large compared to the wight of soil grains. By this reason the settling and consolidation behavior of hydraulically filled quite different from that of Stokes law. This study investigated the settling and consolidation behavior of hydraulically filled materials of Yeochon industrial complex by large scale laboratory settling & consolidation container. The test results showed tat actual settling speed of soil grains in quite large compared to that of Stokes law. It was turned out that this phenomenon was due to the aggregation of soil grains. Also, it was truned out that the void ration and water content after the completion of settling process was 8.7 and 322% respectively. The consolidtion settlement of clayey hydraulic fill material was predicated better by "incremental small strain" consolidation concept than classical Terzaghj's consolidation concept (infinitesimal strain).

• Mycobiology
• /
• v.46 no.3
• /
• pp.287-295
• /
• 2018

In this study, we evaluated the effect of different temperatures (10, 20, 30, and $40^{\circ}C$) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.183-183
• /
• 2022

This study was aimed to investigate the content of avenanthramides(AVNs) and other phenolic compounds in the grains of a naked oat cultivar, Daeyang, which were seeded in the fall and spring, and examine the effects of alcohol extracts from the grains on natural killer(NK) cell activity in vitro. The content of AVN-A, AVN-B, and AVN-C in the spring-seeded oat grains was 2.2 folds higher than the fall-seeded oat grains on average. Among these AVNs, the content of AVN-C was 1.9-folds higher in the spring-seeded oat grains(66.1㎍/g), comparing to the content in the fall-seeded oat grains(34.8㎍/g). The content of other phenolic compounds, such as phenolic acids and flavonoids in the spring-seeded oat grains was 1.1~4.7-folds higher than the fall-seeded oat grains. In particular, sinapinic acid was the most abundant phenolic acid in the spring-seeded oat grains(50.0㎍/g) and its content was 2.4-folds higher than its content in the fall-seed oat grains. Furthermore, NK cell activity in vitro treated with the spring-seeded oat grain extracts was 158%, and it was 18%p higher than NK cell activity treated with the extracts from the fall-seeded oat grain extracts. Our finding suggest that the bioactive properties of naked oat grains would be enhanced by spring seeding.

• Journal of Astronomy and Space Sciences
• /
• v.11 no.2
• /
• pp.165-174
• /
• 1994

We have investigated the chemical composition of dust grains in novae by computing the model spectra for the novae that showed temporary infrared developments shortly after their optical explosions. We find that a simple spherical dust shell models with hot blackbody central sources fit observations fairly well. Optical properties of dust grains deduced from modeling of AGB stars have been used for present calculations. We find that amorphous carbon grains appear to be the major infrared re-emission sources for the carbon-rich nova shells, and the silicate grains for the oxygen-rich nova shells.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.27 no.1
• /
• pp.1-10
• /
• 1982

Degree of grain shattering which is of varietal character is an important determinant for the magnitude of field loss of grains during harvest and threshing. Seven Indica \times Japonica progeny varieties and four Japonica varieties were subjected to measurements of tensile strength of grains, degree of grain shattering when panicles were dropped at 1.5m above concrete floor, and moisture content of grains (wet basis) during a period 35 to 63 days after heading. In addition, two varieties were tested for the relation of tensile strength of grains to the magnitude of field loss of grains in actual binder harvest. The 11 varieties differed conspicuously in tensile strength of grains and the degree of grain shattering: the weakest average tensile strength of grains of a variety was about 90g and the strongest about 250g with varying standard deviation of 30 to 60g. Three Indica \times Japonica varieties and one Japonica variety shattered I to 30% of the grains under the falling test. The threshold tensile strength of grains allowing grain shattering was estimated to be 180g on average for a sampling unit of 10 panicles, but only the grains having tensile strength weaker than 98g within the samples shattered. A decrease in average tensile strength by 10g below the threshold value corresponded to an increase of 3 to 5% in grain shattering. Most varieties did not change appreciably the tensile strength of grains and degree of grain shattering with delay in time of harvest and showed a negative correlation between the tensile strength and the moisture content of grains. The average tensile strength of grains was negatively correlated linearly with field loss in binder harvest. The average tensile strength for zero field loss in binder harvest was estimated to be 174g and a decrease in the average tensile strength by 10g corresponded to an increase of 40kg per hectare in field loss of grains. Instead of the average tensile strength of grains, the percentage of grains having tensile strength weaker than 100g is recommended as a criterion for the estimation of field loss of grains during harvesting operations as well as a basis of variety classification for grain shattering, since the standard deviation of tensile strength of grains varies much with variety and time of harvest, and individual grains having tensile strength stronger than 98 did not shatter practically.

• Journal of the korean society of oceanography
• /
• v.34 no.2
• /
• pp.113-121
• /
• 1999

Glauconite grains are widely distributed in the outer shelf surficial sandy sediments of the Korean continental shelves. Morphologically, these grains are characterized by ovoidal-shaped pellets with bulbous exterior, greenish color and moderately well polished surface. In thin sections, the glauconite grains are massive and contain numerous impurities composed mainly of quartz, feldspar and mica. The morphologies and microscopic examinations indicate mainly fecal pellet as a parent matierials for glauconite. SEM examination shows that glauconitic smectite crystals grow in pores and along fractures of the host grains, commonly as a boxwork arrangement or rosette clusters of blades. Bulbous external shape, high potassium content and rosette-shaped smectite structure, reflect the evolved stage (more than 10$^4$ years in age) of glauconite authigenesis. Moreover, the association of the glauconite grains with the relict sandy sediments on the outer shelf, impliesthat the glauconite grains are geologically old, or at least have formed under the environmental conditions different from the present shelf. The widespread occurrence of the glauconite grains, therefore, might be primarily related with redeposition of sediments transported from the outer shelf during Holocene transgression.

• Journal of Mushroom
• /
• v.12 no.4
• /
• pp.237-243
• /
• 2014

Spawn is the vegetative growth of the mycelium and serves as the inoculum or seed for cultivating mushrooms. Various cereal grains, such as wheat, millet, barley, sorghum, brown rice, rye, and oat were assessed to compare their characteristics and suitability for spawn production of button mushroom (Agaricus bisporus). The mycelial growth rates, density, and the number of completely colonized grains were measured from the twentieth day of inoculation. Wheat grains showed fastest mycelial growth with 8.4 cm followed by rye, oat, barley with 8.2, 7.5 and 7.3 cm, respectively. In the mycelial density, foxtail millet, barley, and sorghum were best compared with that of wheat grains. Especially, the number of grains which were completely colonized by mycelia were greatest in foxtail millet with 5,123 grains followed by proso millet, and wheat with 3,052 and 914, respectively. Based on the results obtained, barley, foxtail millet, and sorghum grains would be appropriate substituting for wheat grain in spawn production of button mushroom.