• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.95-106
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• 1998

A study was made to estimate the economic level(Necon.) of mineral nitrogen and a cutting frequency for the dry matter production of reed canarygrass(Phalaris arundinacea L.) in uncultivated rice paddy during the harvested years in 1993~1995. Annual mineral nitrogen was applied at the levels of 0, 90, 180, 270 and 360 kg $ha^{-1}$ in 3 cuttings, 0, 120, 240, 360 and 480 kg $ha^{-1}$ in 4 cuttings, and 0, 150, 300, 450 and 600 kg $ha^{-1}$ in 5 cuttings, respectively. The results were summarized as follows; 1. The dry matter yields of all cutting frequencies in 1993 were significantly higher than in the other hay years. Mean dry matter yield were 14.40, 13.88 and 15.98 tons $ha^{-1}$ in 3, 4 and 5 cuttings, respectively. 2. Significantly higher matter yields were obtained as 15.37 and 15.80 tons $ha^{-1}$ at the level of 120 kg $ha^{-1}\;cut^{-1}$ in 3 and 4 cuttings, and 14.02~14.08 tons $ha^{-1}$ levels of 90~120 kg $ha^{-1}$ in 5 cuttings, respectively. 3. Higher efficiencies of dry matter production in response to mineral nitrogen application were recorded as 29.7 kg at level of 90 kg $ha^{-1}\;yr^{-1}$ in 3 cuttings, 19.6 kg at level of 240 kg $ha^{-1}\;yr^{-1}$ in 4 cuttings, and 20.1 kg at level of 150 kg $ha^{-1}\;yr^{-1}$ in 5 cuttings, respectively. 4. Significantly higher matter yields appeared as 5.02 tons $ha^{-1}$ at 2nd cut in 3 cuttings, 3.94~4.37 tons $ha^{-1}$ at 2nd and 3rd cut in 4 cuttings, and 3.81~3.58 tons $ha^{-1}$ at 2nd and 3rd cut in 5 cuttings, respectively. 5. The highest values of relative dry matter yield were 40.4% for 2nd cut in 3 cuttings, 34.9% for 3rd cut in 4 cuttings, and 31.5% for 2nd cut in 5 cuttings, respectively. 6. The estimated marginal dry matter yields(Ymar.) were 13.8~14.7 tons $ha^{-1}$ at ranges of economic N level of 228.5~291.9 kg $ha^{-1}\;yr^{-1}$ in 3 cuttings, 13.8~14.2 tons $ha^{-1}$ at ranges of 293.5~335.7 kg $ha^{-1}\;yr^{-1}$ in 4 cuttings, and 12.2~12.8 tons $ha^{-1}$ at ranges of 237.5~302.5 kg $ha^{-1}\;yr^{-1}$ in 5 cuttings, respectively. 7. Maximun dry matter yields(Ymax.) were 17.0 tons at the level of limiting N(Nmax.) of 558.9 kg $ha^{-1}\;yr^{-1}$ in 3 cuttings, 16.1 ton at level of limiting N of 531.4 kg $ha^{-1}\;yr^{-1}$ in 4 cuttings, and 13.9 ton at level of limiting N of 546.3 kg $ha^{-1}\;yr^{-1}$ in 5 cuttings, respectively. 8. Economic N level in all cuts were in the ranges of 42.6~123.8 kg $ha^{-1}$ in 3 cuttings, 27.3~144.1 kg $ha^{-1}$ in 4 cuttings, and 9.3~159.4 kg $ha^{-1}$ in 5 cuttings, respectively. 9. The proper cutting frequency for matter production of reed canarygrass was 3 cuttings during the h harvested years in 1993~1995, due mainly to the higher efficiency of N for the dry matter production.

• Computers and Concrete
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• v.11 no.2
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• pp.123-148
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• 2013

The nonlinear finite element method with eight noded isoparametric quadrilateral element for concrete and two noded element for reinforcement is used for the prediction of the behavior of reinforcement concrete structures. The disturbed state concept (DSC) including the hierarchical single surface (HISS) plasticity model with associated flow rule with modifications is used to characterize the constitutive behavior of concrete both in compression and in tension which is named DSC/HISS-CT. The HISS model is applied to shows the plastic behavior of concrete, and DSC for microcracking, fracture and softening simulations of concrete. It should be noted that the DSC expresses the behavior of a material element as a mixture of two interacting components and can include both softening and stiffening, while the classical damage approach assumes that cracks (damage) induced in a material treated acts as a void, with no strength. The DSC/HISS-CT is a unified model with different mechanism, which expresses the observed behavior in terms of interacting behavior of components; thus the mechanism in the DSC is much different than that of the damage model, which is based on physical cracks which has no strength and interaction with the undamaged part. This is the first time the DSC/HISS-CT model, with the capacity to account for both compression and tension yields, is applied for concrete materials. The DSC model allows also for the characterization of non-associative behavior through the use of disturbance. Elastic perfectly plastic behavior is assumed for modeling of steel reinforcement. The DSC model is validated at two levels: (1) specimen and (2) practical boundary value problem. For the specimen level, the predictions are obtained by the integration of the incremental constitutive relations. The FE procedure with DSC/HISS-CT model is used to obtain predictions for practical boundary value problems. Based on the comparisons between DSC/HISS-CT predictions, test data and ANSYS software predictions, it is found that the model provides highly satisfactory predictions. The model allows computation of microcracking during deformation leading to the fracture and failure; in the model, the critical disturbance, Dc, identifies fracture and failure.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1715-1720
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• 2005

Two promising varieties of forage sorghum viz. HD-15 and J. Sel-10 were identified for their higher forage yield (350-400 quintals per hectare) compared to traditional/existing variety, HC-136 at Indian Grassland and Fodder Research Institute, Jhansi. Silage of these three forage sorghum varieties viz., HD-15, J.Sel-10 and HC-136 were prepared in three concrete silos for their nutritional evaluation in sheep. Twelve adult Muzaffarnagari Ewes, divided into three equal groups of 4 each, were offered a particular variety of sorghum silage ad libitum over a period of 30 days followed by a 6 day metabolism trial and a collection of rumen liquor and blood samples. The HD-15 variety of forage sorghum silage contained higher crude protein (CP) than both the J.Sel-10 and HC-136. Average daily dry matter (DM) intake (% of live weight) differed significantly (p<0.05) in sheep that were fed the different varieties of silage, with the maximum amount in HD-15 (2.55) followed by J.Sel-10 (2.49) and HC-136 (1.84). The average apparent digestibility of all the nutrients was low in the sheep that were fed the HC-136 variety of sorghum silage when compared to both HD-15 and J.Sel-10. However, digestibility of organic matter (p<0.05) and crude protein (p<0.01) was significantly low in the HC-136 variety. The average daily nitrogen retention was-0.19, 2.15 and 0.42 g in HC-136, HD-15 and J.Sel-10, respectively which differed significantly (p<0.01). The average digestible crude protein and total digestible nutrient (TDN) contents (%) of the silage varieties were higher in HD-15 (3.14 and 55.3) than HC-136 (0.25 and 58.6) and J.Sel-10 (1.58 and 55.3) varieties. On comparing to the maintenance requirements (ICAR, 1985) for dry matter, crude protein and total digestible nutrients, both the improved varieties (HD-15 and J.Sel-10) almost met the requirements except crude protein, which met only 73.3% of the requirement by J.Sel-10, while the HC-136 variety was unable to meet the requirements. The average rumen pH and total volatile fatty acids concentrations were comparable among the groups. However, concentrations of nitrogen metabolites were higher in the animals fed the HD-15 variety of silage. Varieties of sorghum silage also did not have any influence on the concentration of the blood metabolites. It was concluded that the HD-15 variety of sorghum silage was nutritionally superior to both J.Sel-10 and HC-136 silage.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.124-129
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• 2016

The extraction and purification of the anti-hyperglycemic α-glucosidase inhibitor from an edible mushroom, Pleurotus cornucopiae, were investigated. The inhibitor was maximally extracted when the P. cornucopiae fruiting body was treated with distilled water at 30℃ for 12 h. Purification was achieved using Sephadex G-100 and G-50 filtration chromatography, pepsin hydrolysis, and reverse-phase HPLC. The compound’s solid yield and inhibitory activity were 12.2% and 9.10 mg/ml of IC₅₀, respectively. The purified inhibitor contained two hexapeptides with Thr-Ile-Ala-Phe-Ile-Asp (A) and Tyr-Tyr-Ala-Ile-Gly-Asp (B) sequences and molecular weights of 678.79 Da (A) and 643.7 Da (B). The purified inhibitor showed a mixed inhibition pattern to α-glucosidase and a dose-dependent anti-hyperglycemic effect in a streptozotocininduced diabetic Sprague-Dawley rat model, exhibited by decreased blood glucose levels at doses of 50 and 300 mg/kg.

• Applied Biological Chemistry
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• v.25 no.2
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• pp.105-109
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• 1982

The effect the physiochemical properties of red and white ginseng powder after $^{60}Co-{\gamma}$ ray irra diationduring the storage for 4 months at $25^{\circ}C$ was investigated. The storage periods and the treatment of irradation at various doses on ginseng powders has no significant effect on the proximate composition and color density of ginseng extract with 50% ethanol. No changes in the contents of saponin and its HPLC patterns were found during the storage. However, a little increase was found in the yield of 50% ethanol extract and Hunter's color value of powder. But generally it was found to be stable in the physicochemical properties of red and white ginseng powder by irradiation of the intensity during the storage.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.3-11
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• 1987

The study was conducted to identify growth habit of Monochoria vaginalis gathered from three different locations (Suweon, Jeonju and Milyang). The plant height, number of leaves and dry weight of M. vaginalis gathered from three different locations were greatly affected by the seeding dates. The earlier the seeds of M. varginalis sown, the greater M. vaginalis grew, In general, the earlier seeding dates produced significantly longer plant height, number of leaves and dry weight than those of later seeding dates, showing no difference in the collection of weed seeds in different locality. The earlier seeding dates resulted in the earlier flowering, but the interval between dates of seeding and flowering decreased progressively as the seeding times were delayed. Seed production was not significant among three locations and but seeding date on June 15 produced th highest seed production as compared with other seeding times. No. of flowers and capsule per pot among yield components were two major factors affecting seed production.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.647-653
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• 2010

The objectives of this research are to evaluate and compare the oxygen transfer coefficients($K_{La}$) in both a general bubbles reactor and a micro-nano bubbles reactor for effective operation in sewage treatment plants, and to understand the effect on microbial kinetic parameters of biomass growth for optimal biological treatment in sewage treatment plants when the micro-nano bubbles reactor is applied. Oxygen transfer coefficients($K_{La}$) of tap water and effluent of primary clarifier were determined. The oxygen transfer coefficients of the tap water for the general bubbles reactor and micro-nano bubbles reactor were found to be 0.28 $hr^{-1}$ and 2.50 $hr^{-1}$, respectively. The oxygen transfer coefficients of the effluent of the primary clarifier for the general bubbles reactor and micro-nano bubbles reactor were found be to 0.15 $hr^{-1}$ and 0.91 $hr^{-1}$, respectively. In order to figure out kinetic parameters of biomass growth for the general bubbles reactor and micro-nano bubbles reactor, oxygen uptake rates(OURs) in the saturated effluent of the primary clarifier were measured with the general bubbles reactor and micro-nano bubbles reactor. The OURs of in the saturated effluent of the primary clarifier with the general bubbles reactor and micro-nano bubbles reactor were 0.0294 mg $O_2/L{\cdot}hr$ and 0.0465 mg $O_2/L{\cdot}hr$, respectively. The higher micro-nano bubbles reactor's oxygen transfer coefficient increases the OURs. In addition, the maximum readily biodegradable substrate utilization rates($K_{ms}$) for the general bubbles reactor and micro-nano bubbles reactor were 3.41 mg COD utilized/mg active VSS day and 7.07 mg COD utilized/mg active VSS day, respectively. The maximum specific biomass growth rates for heterotrophic biomass(${\mu}_{max}$) were calculated by both values of yield for heterotrophic biomass($Y_H$) and the maximum readily biodegradable substrate utilization rates($K_{ms}$). The values of ${\mu}_{max}$ for the general bubbles reactor and micro-nano bubbles reactor were 1.62 $day^{-1}$ and 3.36 $day^{-1}$, respectively. The reported results show that the micro-nano bubbles reactor increased air-liquid contact area. This method could remove dissolved organic matters and nutrients efficiently and effectively.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.29-34
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• 1970

This experiment was conducted to investigate the influence of amounts of lime dressed on the growth of rice by the treatment of percolation and nonpercolation in the acid sulphate soil. And also analysis of soil chemical components after treatment was carried out. The results obtained were summarized as follows: 1. In the initial stage of growth, number of tillers and plant length showed no distinct differences between the treatments of percolation and nonpercolation, but after August the effect of lime appeared and the percolation treatment was more effective than the nonpercolation. 2. Lime dressing affected good influence on the panicles, grain per panicles and the rate of grain formation, and the treatment of percolation showed better results than nonpercolation. 3. If the yield of rough rice in the control (nonpercolation and lime dressing) was 100, it was 194 in the treatment of nonpercolation 12me/100gr of lime dressed, 268 in the treatment of percolation-4me/100gr of lime and 315 in the 8me/100gr-percolation. 4. Lime dressing affected good influence on the control of Helminthosporium leaf spots. 5. In the case of lime dressing, amounts of available phosphate and soluble silicon dioxide were increased, but ferrous ion ($Fe^{{+}{+}}$) were decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.105-109
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• 2001

Poorly drained coarse textured paddy soils has harmful substances(e.g. $Fe^{2+}$, $H_2S$, organic acid etc.) due to reduction condition, and lower soil temperature during early stage of rice crop. The roots of the rice plant usually were distributed in the surface layer, and prone to lodged. To solve the problems, the study was carried out in the typical poorly drained, sandy loam textured paddy soils during 1997-1998. Coated urea and urea fertilizers were applied on the surface and whole layer mixed respectively. Yield of the surface fertilization of coated urea had increasing tendency but not significant. Advantages of this experiment was saving of about 30% of nitrogen fertilizer and top dressing labour, which would reduce possibility of water pollution.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.1-11
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• 1998

This experiment was conducted to investigate weed infestation and to determine effective weed control methods in direct-seeded rice. Twenty two weed species occurred in dry- and water-seeded rice, which was mainly composed of annual weeds. Dominant weed species in dry-seeded rice were Cyperus difformis, Echinochloa crus-galli, Aneilema keisak and Digitaria sanguinalis in discending order. Dominant weed species in water-seeded lice were E. crus-galli, C. difformis, Monochoria vaginalis and Scirpus juncoides. E. crus-galli emerged at 7 days after sowing. In water-seeded rice, E. crus-galli emerged at 5 days after sowing, and M vaginalis, S. juncoides and C. difformis at 8~10 days after sowing. Mean days to emerge important weeds was 20 days in dry-seeded rice and 13 days in water-seeded rice. Leaf development of weeds was faster than that of rice in dry-seeded rice. In water-seeded rice, E eras-galli was more vigorous than rice, but leaf development of other weeds were slower than that of rice. Changes in number of weeds and dry weight oil weed species varied depending upon weed species in the direct-seeded rice. Dry weight of weeds were increased greatly from 30 days to 60 days after sowing in dry-seeded rice. Number of weeds tended to increase up to 40 days after sowing drastically, and then trend of the increase was dull thereafter. Dry weight and number of weeds increased up to 20~60 days after sowing in water-seeded rice. Most effective herbicide treatments was foliar application of cyhalofop/bentazon at 20 days after sowing followed by fenoxaprop/bentazon at 45 days after sowing in dry-seeded rice. All herbicide treatments except foliar applications were very effective to control weeds in water-seeded rice. Slight phytotoxicity was observed in foliar applied fenoxaprop/bentazon at 45 days after sowing in water-seeded rice, but it did not affect rice yield.