• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.98-133
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• 1987

The mechanical and rheological properties of agricultural materials are important for engineering design and analysis of their mechanical harvesting, handling, transporting and processing systems. Agricultural materials, which composed of structural members and fluids do not react in a purely elastic manner, and their response when subjected to stress and strain is a combination of elastic and viscous behavior so called viscoelastic behavior. Many researchers have conducted studies on the mechanical and rheological properties of the various agricultural products, but a few researcher has studied those properties of rice plant, and also those data are available only for foreign varieties of rice plant. This study are conducted to experimentally determine the mechanical and the rheological properties such as axial compressive strength, tensile strength, bending and shear strength, stress relaxation and creep behavior of rice stems, and grain detachment strength. The rheological models for the rice stem were developed from the test data. The shearing characteristics were examined at some different levels of portion, cross-sectional area, moisture content of rice stem and shearing angle. The results obtained from this study were summarized as follows 1. The mechanical properties of the stems of the J aponica types were greater than those of the Indica ${\times}$ Japonica hybrid in compression, tension, bendingand shearing. 2. The mean value of the compressive force was 80.5 N in the Japonica types and 55.5 N in the Indica ${\times}$ Japonica hybrid which was about 70 percent to that of the Japonica types, and then the value increased progressively at the lower portion of the stems generally. 3. The average tensile force was about 226.6 N in the Japonica types and 123.6 N in the Indica ${\times}$ Japonica hybrid which was about 55 percent to that of the Japonica types. 4. The bending moment was $0.19N{\cdot}m$ in the Japonica types and $0.13N{\cdot}m$ in the Indica ${\times}$ Japonica hybrid which was 68 percent to that of the Japonica types and the bending strength was 7.7 MPa in the Japonica types and 6.5 MPa in the Indica ${\times}$ Japonica hybrid respectively. 5. The shearing force was 141.1 N in Jinju, the Japonica type and 101.4 N in Taebaeg, the Indica ${\times}$ Japonica hybrid which was 72 percent to that of Jinju, and the shearing strength of Taebaeg was 63 percent to that of Jinju. 6. The shearing force and the shearing energy along the stem portion in Jinju increased progressively together at the lower portions, meanwhile in Taebaeg the shearing force showed the maximum value at the intermediate portion and the shearing energy was the greatest at the portion of 21 cm from the ground level, and also the shearing strength and the shearing energy per unit cross-sectional area of the stem were the greater values at the intermediate portion than at any other portions. 7. The shearing force and the shearing energy increased with increase of the cross-sectional area of the rice stem and with decrease of the shearing angie from $90^{\circ}$ to $50^{\circ}$. 8. The shearing forces showed the minimum values of 110 N at Jinju and of 60 N at Taebaeg, the shearing energy at the moisture content decreased about 15 percent point from initial moisture content showed value of 50 mJ in Jinju and of 30 mJ in Taebaeg, respectively. 9. The stress relaxation behavior could be described by the generalized Maxwell model and also the compression creep behavior by Burger's model, respectively in the rice stem. 10. With increase of loading rate, the stress relaxation intensity increased, meanwhile the relaxation time and residual stress decreased. 11. In the compression creep test, the logarithmic creep occured at the stress less than 2.0 MPa and the steady-state creep at the stress larger than 2.0 MPa. 12. The stress level had not a significant effect on the relaxation time, while the relaxation intensity and residual stress increased with increase of the stress level. 13. In the compression creep test of the rice stem, the instantaneous elastic modulus of Burger's model showed the range of 60 to 80 MPa and the viscosities of the free dashpot were very large numerical value which was well explained that the rice stem was viscoelastic material. 14. The tensile detachment forces were about 1.7 to 2.3 N in the Japonica types while about 1.0 to 1.3 N in Indica ${\times}$ Japonica hybrid corresponding to 58 percent of Japonica types, and the bending detachment forces were about 0.6 to 1.1 N corresponding to 30 to 50 percent of the tensile detachment forces, and the bending detachment of the Indica ${\times}$ Japonica hybrid was 0.1 to 0.3 N which was 7 to 21 percent of Japonica types. 15. The detachment force of the lower portion was little bigger than that of the upper portion in a penicle and was not significantly affected by the harvesting period from September 28 to October 20. 16. The tensile and bending detachment forces decreased with decrease of the moisture content from 23 to 13 percent (w.b.) by the natural drying, and the decreasing rate of detachment forces along the moisture content was the greater in the bending detachment force than the tensile detachment force.

• Journal of the Korean Society of International Agriculture
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• v.31 no.3
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• pp.249-254
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• 2019

'Japonica 6' is a japonica rice variety developed from a cross between 'MS11', the beginning variety adaptable to tropical region, and 'IR86743-28-1-4', an elite line of high yield and good plant type by a Korea(RDA)-IRRI cooperative breeding program at IRRI in 2017. The growth duration of 'Japonica 6' is 121 days from sowing to harvest. It is 10 days later than that of the check variety 'MS11'. The culm length of 'Japonica 6' is 70 cm, and 1,000-brown rice grain weight is 26.7 g. It has a shorter culm and a larger grain. size than that of MS11. 'Japonica 6' is moderately resistant to blast disease but susceptible to bacterial blight, tungro virus and plant hoppers. The milled rice recovery rate of 'Japonica 6' is improved than that of 'MS11'. The head rice rate of 'Japonica 6' is significantly higher than that of 'MS11'. Yield of 'Japonica 6' is averagely 3.59 MT/ha of milled rice in 5 areas of the Philippines. The 'Japonica 6' was registered in Philippines and would be adaptable to the diverse regions of tropical Asia (Registration No in Philippines. BPI-NSIC-2017-Rc 484SR).

• KIEAE Journal
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• v.12 no.4
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• pp.77-82
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• 2012

This study conducted the experiment of reduction of Volatile Organic Compounds(VOCs) and Formaldehyde concentration by Native plants, Fatsia japonica and Ardisia pusilla. The two plants are advantageous in that they are highly available as they grow wild, and being easy to get. Fatsia japonica is a plant of its wide and large leaf diverged 7 or 8 parts, which is thought to have a high effect of air purification. Ardisia pusilla has a smaller leaf than Fatsia japonica, which is characterized by more leaves and beautiful. Field measurements were performed using Fatsia japonica and Ardisia pusilla which were verified as air-purifying plants in Korea. The effect of reducing the concentration of VOCs and Formaldehyde by plant studied in a full scale mock-up model. The dimensions of the two models were equal. The concentration of Benzene, Toluene, Ethylbenzene, Xylene, Stylene, Formaldehyde were monitored, since they were known as most toxic materials. The concentration of VOCs was monitored three hours after the plants were placed and three days after the plants were placed. Field measurements were performed in models where the plants were placed and were not. As a result, they had all an effect of reducing pollution. In all cases of experiment of planting and growing volume, the more planting volume, the more excellent the effect. Toluene was more effective in Fatsia japonica and Ardisia pusilla planted, Formaldehyde was more effective in Fatsia japonica planted respectively. In planting and growing and placing experiment, the placement at sunny spot was more effective than that at scattered growing. When Fatsia japonica was placed at sunny spot, the reduction effect of Formaldehyde was the most excellent, and when Ardisia pusilla was placed at sunny spot, the reduction effect of Toluene was the most effective.

• Culinary science and hospitality research
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• v.15 no.4
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• pp.28-36
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• 2009

The purpose of this study is to evaluate the quality and sensory characteristics of soybean dasik prepared by additions of Dioscorea japonica flour. As the Dioscorea japonica contents flour level in the formula increased, the moisture contents of the samples increased. The lightness values, redness values and yellowness values decreased with Dioscorea japonica flour increased. In the mechanical evaluation, hardness increased with the amount of Dioscorea japonica flour increased, and cohesiveness, gumminess and chewiness decreased with the amount of Dioscorea japonica flour increased. Adhesiveness and springiness did not show significant difference according to the level of Dioscorea japonica flour. In conclusion, soybean dasik with 6% of Dioscorea japonica flour was most proper in taste, flavor and overall acceptability.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.11
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• pp.1238-1243
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• 2005

The batch experiments of biosorption were carried out for the removal of lead ion from metal solution using Laminaria japonica and Kjellmaniella crassifolia, two species of marine algaes as biosorbent. We have investigated biosorption kinetics and equilibrium of lead by using marine algaes. We observed that biosorption of lead occurred very rapidly by marine algaes ; the biosorption reached equilibrium less than 2 hr. These experimental data could be accurately described by a pseudo-second-order rate equation, obtaining values between $0.883{\times}10^{-3}$ and $0.628{\times}10^{-3}\;g/mg/min$ for the biosorption rate constant $k_{2,ad}$. It could be described with Langmuir, Redlich-Peterson, and Koble-Corrigan(Langmuir-Freundlich) equation. The biosorption capacity by L. japonica and K. crassifolia were in the sequence of Pb>Cd>Cr>Cu and Pb>Cu>Cd>Cr, respectively. The biosorption capacity of L. japonica were increased with pH increasing.

• Environmental Analysis Health and Toxicology
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• v.29
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• pp.2.1-2.7
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• 2014

Objectives Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone important in the maturation of a broad spectrum of protein. In this study, an HSP90 gene was isolated from Asian paddle crab, Charybdis japonica, as a bio-indicator to monitor the marine ecosystem. Methods This work reports the responses of C. japonica HSP90 mRNA expression to cellular stress by endocrine disrupting chemicals (EDCs), such as bisphenol A (BPA) and 4-nonylphenol (NP) using real-time. reverse transcription polymerase chain reaction. Results The deduced amino acid sequence of HSP90 from C. japonica shared a high degree of homology with their homologues in other species. In a phylogenetic analysis, C. japonica HSP90 is evolutionally related with an ortholog of the other crustacean species. The expression of HSP90 gene was almost distributed in all the examined tissues of the C. japonica crab but expression levels varied among the different body parts of the crabs. We examined HSP90 mRNA expression pattern in C. japonica crabs exposed to EDCs for various exposure times. The expression of HSP90 transcripts was significantly increased in C. japonica crabs exposed to BPA and NP at different concentrations for 12, 24, 48 and 96 hours. The mRNA expression of HSP90 gene was significantly induced in a concentration- and time-dependent manner after BPA or NP exposures for 96 hours. Conclusions Taken together, expression analysis of Asian paddle crab HSP90 gene provided useful molecular information about crab responses in stress conditions and potential ways to monitor the EDCs stressors in marine environments.

• Journal of Acupuncture Research
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• v.29 no.1
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• pp.67-74
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• 2012

Objectives : The objective of this study is to study the effects of hot aqueous extract and ethanol extract from $Lonicera$ $japonica$ $Flos$ on nitric oxide(NO) and prostaglandin $E_2(PGE_2)$ production in macrophage. Methods : $Lonicera$ $japonica$ $Flos$ was extracted in two ways. One was extracted with distilled water(2L) for 4 h and the other one was extracted with 70% ethanol (2L) for 4h. The RAW 264.7 macrophage was subclutured. In order to evaluate cytotoxicity, MTT assay was performed. The concentrations of NO were measured by Griess assay. The concentrations of $PGE_2$ were measured by enzyme immunoassay. Results : 25, $125{\mu}g/m{\ell}$ hot aqueous extract from $Lonicera$ $japonica$ $Flos$ inhibited NO production in LPS-stimulated RAW 264.7 macrophages significantly. 25, 125, $625{\mu}g/m{\ell}$ ethanol extract from $Lonicera$ $japonica$ $Flos$ inhibited NO production in LPS-stimulated RAW 264.7 macrophages significantly. 150, $200{\mu}g/m{\ell}$ hot aqueous extract and ethanol extract from $Lonicera$ $japonica$ $Flos$ inhibited $PGE_2$production in LPS-stimulated RAW 264.7 macrophages significantly. Conclusions : This study suggests that hot aqueous extract and ethanol extract from $Lonicera$ $japonica$ $Flos$ suppress NO and $PGE_2$ production. So hot aqueous extract and ethanol extract from $Lonicera$ $japonica$ $Flos$ may have an anti-inflammation effect.

• The Korean Journal of Malacology
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• v.17 no.1
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• pp.63-70
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• 2001

The distribution and seasonal changes of the intertidal macrobenthos community was performed on five intertidal rocky stations of Hwasoon at Jeju Islands September 1999 to August 2000. The macrobenthos was composed of six phyla, 13 classes, 24 orders, 49 families, and 97 species. The dominant species of the upper zones were Nodilittorina exigua, Notoacmea schrenckii, Liolophura japonica and Patelloida saccharina. Those of the middle zones were Monodonta labio, Chthamalus challengeri, Siphonalia japonica and Liolophura japonica. Those of the lower zones were Siphonalia sirius, Patelloida saccharina, Chthamalus challengeri, and Liolophura japonica. The community dominance indices of the upper zones were much higher than those of the middle and lower zones. Species diversity and evenness in all investigated zones were highest in station 1 and lowest in staton 3. But, species richness was highest in station 1 and lowest in station 4.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.327-334
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• 2015

We investigated the current and potential spatial distributions and habitable areas of Biston robustum and Camellia japonica in South Korea in order to provide useful data for the conservation of C. japonica and minimize the damage caused by B. robustum. It was predicted that, by 2070, although B. robustum would be widely distributed throughout the Korean Peninsula, except for the western and eastern coastal areas, it would be narrowly distributed along the Sokcho-si and Goseong-gun coastlines in Gangwon Province. C. japonica is currently located along the southern coastline but its critical habitable area is predicted to gradually disappear by 2070. Assessment of the potential distribution probabilities of B. robustum and C. japonica revealed that the area under the curve (AUC) values were 0.995 and 0.991, respectively, which indicate high precision and applicability of the model. Major factors influencing the potential distribution of B. robustum included precipitation of wettest quarter and annual precipitation (BIO16 and BIO12), whereas annual mean temperature and mean temperature of wettest quarter (BIO1 and BIO8) were important variables for explaining C. japonica distribution. Overlapping areas of B. robustum and C. japonica were $11,782km^2$, $5447km^2$, and $870km^2$ for the current, 2050-predicted, and 2070-predicted conditions, respectively, clearly showing a dramatic decrease in area. Although it is predicted that B. robustum would cause continuous damage to C. japonica in the southern part of the Korean Peninsula, such impacts might diminish over time and become negligible in the future.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.3
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• pp.53-63
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• 2014

This study was carried out to investigate the growth responses of medicinal plants such as Glehnia littoralis, Cryptotaenia japonica, Angelica gigas, Reynoutria japonica, Saururus chinensis, Houttuynia cordata, Ligularia fischeri, and Aralia cordata under 70%-shading and full sunlight conditions on a rooftop condition using artificial soil as a growth media. Glehnia littoralis, Cryptotaenia japonica, Ligularia fischeri, Saururus chinensis, and Houttuynia cordata showed better growth on plant height, leaf length, leaf width, petiole length and leaf number under full sunlight conditions on a rooftop condition. Cryptotaenia japonica and Houttuynia cordata had high value of Hunter's a (red-green) under full sunlight, while had lower value of L(lightness) and b(blue-yellow) than those of 70% shading condition. As an index of plant stress response, Glehnia littoralis, Reynoutria japonica, Houttuynia cordata, Ligularia fischeri showed Fv/Fm values 0.79~0.84 under full sunlight in August, indicating low stress on plant growth. Therefore they seemed to be suitable medicinal plats for rooftop conditions. Ligularia fischeri and Reynoutria japonica showed better growth under 70% shading treatment in August, while showed high growth response under full sunlight conditions in September. The 70% shading treatment was effective for the growth of Angelica gigas, Reynoutria japonica, and Aralia cordata. Angelica gigas and Reynoutria japonica, however, showed better plant growth under full sunlight during summer. The results showed that Glehnia littoralis, Cryptotaenia japonica, Ligularia fischeri, Saururus chinensis, and Houttuynia cordat seemed to be suitable medicinal plants for rooftop garden where there is a full sunlight condition.