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Volume 39 (2008 - 200･･･
- Issue 4 Pages 243-
- Issue 3 Pages 183-
- Issue 2 Pages 95-
- Issue 1 Pages 1-
Volume 39, Issue 2
Displaying 1-6 of 6 articles from this issue
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Kazuya SHIMIZU, Kunihiro OKANO, Yingnan YANG, Motoo UTSUMI, Zhenya ZHA ...2008 Volume 39 Issue 2 Pages 95-104
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSImprovement of microbial ammonia oxidation method using a rockwool as a carrier in wastewater treatment was examined through batch and continuous operation. In batch operation, a nitrifying bacterium, Nitrosomonas europaea (NBRC 14298), and phosphorus and iron-complexes were highly attached to the rockwool. In continuous operation, the operation with rockwool (RW) was shortened the hydraulic retention time (HRT) from 20h to 10h, and the maximum ammonia removal ratio was 87.5%. The average of ammonia removal ratio was performed 73.1%, 78.2% at 20h and 10h, respectively, at aeration rate of 3000ml·min-1. The ammonia oxidation rate was 22.3mg-N·l-1-carrier·h-1 when the ammonia loading rate was 25.5mg-N·l-1-carrier·h-1. Quantitative PCR results revealed that around 1015 cells·l-1-carrier were immobilized to the RW. Therefore, the RW could retain a large number of nitrifying bacteria, improve the degree of nitrification and have widely application.View full abstractDownload PDF (2503K) -
Measuring local numbers of ventilation in the environmental controlled greenhouse of fruit treesNorihiro HOSHI, Kiyoshi HIRAOKA, Masahiko SHIMAZAKI, Kunihisa MORINAGA ...2008 Volume 39 Issue 2 Pages 105-112
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSA technique using an aerosol and optical sensors was introduced to estimate local ventilation efficiency in the environmental controlled glasshouse of fruit trees. After filling aerosol as optical tracer, instead of the tracer-gas like CO2, and mechanically ventilating in the glasshouse, laser beam is irradiated to the evaluating areas of the glasshouse and the increasing curve of laser signals according to the attenuation of aerosol content is measured to estimate the local numbers of ventilation in the glasshouse.
The number of ventilation calculated from the exhaust air flow rate was 30.3hr-1. On the other hand, the values of local number of ventilation measured by the method were ranged from 1.05 to 39.6hr-1. This is shown that there are clear dispersions in local numbers of ventilation which mean non-homogeneous condition in the glasshouse. The performance of ventilation system would be evaluated by using the optical method, especially when the ventilation rate is row.View full abstractDownload PDF (7309K) -
Shingo MIYAMOTO, Hiroomi ASANO, Kazuhiro SERATA, Manzo UCHIGASAKI2008 Volume 39 Issue 2 Pages 113-120
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSIn recent years, indoor experimental researches concerning the crops cultivation using LED has been increased. Comparing with the usual lighting system used for cultivation, LED light has some advantages. It (LED) can increase the photosynthetic photon flux density by the adjacent irradiation. Moreover, the power consumption of the LED source of lights is lower than the conventional ones. In this research, the influence of LED element while using as a supplementary source of light on the development of flower bud of the miniature rose was examined. The result showed an increasing tendency of flowers, buds as well as new shoots with a level (p<0.005) of significance while using LED lights as the supplementary source of power along with the fluorescent lamps usually used for domestic uses. When the miniature rose were exposed to different optical quality, even the level of significance could not be obtained, a tendency of early flowering was observed while using LED lights as the supplementary source. Therefore, it can be concluded that supplementary LED source of power had positive effect on plant growth of miniature rose.View full abstractDownload PDF (6201K) -
External Wind Pressure Coefficients on Enclosed StructuresYasushi UEMATSU, Koichi NAKAHARA, Hideki MORIYAMA, Sadanori SASE2008 Volume 39 Issue 2 Pages 121-132
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSWind loads for designing the structural frames of pipe-framed greenhouses have been studied based on a series of wind-tunnel experiments with two kinds of pipe-framed greenhouse models. The present paper focuses on enclosed greenhouses with no openings. Wind pressure distributions on two or three typical cross-sections were measured in a turbulent boundary layer simulating natural winds over typical open-country exposure for various wind directions. The measurements were made in two different wind tunnels, which are quite different in size from each other. The LRC (Load Response Correlation) method is employed for estimating the design wind pressures, expressed as equivalent static pressures, with consideration for the time-space correlations of wind pressures. The bending moment at the windward column base is taken into account as the most important load effect. The results of the LRC method are compared with those of a time-history analysis as well as with those predicted from a conventional gust effect factor approach from the viewpoint of load effect. It is found that the largest load effect is induced in a frame near the windward gable wall in an oblique wind not in a central frame in a normal wind. The wind force coefficients for gable and circular arc roofs, which are specified in the current standards, are not necessarily appropriate for pipe-framed greenhouses often used in Japan. The effects of turbulence intensity and scale on the wind pressure distributions are also investigated.View full abstractDownload PDF (5209K) -
Masahisa ISHII, Sadanori SASE, Limi OKUSHIMA, Hideki MORIYAMA, Atsuo I ...2008 Volume 39 Issue 2 Pages 133-140
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSFor wind tunnel testing, it is important to simulate the airflow pattern that has the same characteristics as the outside wind. The purpose of this study was to design vertical wind speed and turbulence intensity profiles with the same characteristics as outside agricultural fields. We used the wind tunnel facility at the National Institute for Rural Engineering (NIRE) in Japan. The vertical profiles of wind speed and turbulence intensity were measured at the center of a turntable placed inside the wind tunnel, using the 1/20 dimensional scale. In this study, the following results were obtained:
(1) The spires, roughness blocks and artificial turfs were arranged until a desirable roughness length was obtained that expressed the surface conditions of outside agricultural fields.
(2) Using logarithmic law, the 1/20 dimensional scaled roughness length of 0.52mm corresponded to a full-scale roughness length of 10.4mm, which corresponded to the roughness of a typical grass field.
(3) It was possible to achieve turbulence intensity values of 0.23 just above the top of the turntable. The obtained turbulence intensity was generally similar compared to the ‘Recommendations for Loads on Buildings’ published by the Architectural Institute of Japan.View full abstractDownload PDF (3880K) -
Focusing on its carbonate ion content as the pH change inhibitorYoshinori KAMITANI, Abdulsudi ISSA-ZACHARIA, Hiromi HIEJIMA, Kazuo MOR ...2008 Volume 39 Issue 2 Pages 141-146
Published: September 25, 2008
Released on J-STAGE: September 05, 2011
JOURNAL FREE ACCESSStrong acid electrolyzed water (SAcEW) is known to contain hypochlorite which has shown to have a strong bactericidal effect. Therefore it has been authorized by the Ministry of Labor and Welfare as medical device for hand washing and food additive in Japan. It is expected as an alternative means for the strong agricultural chemicals currently being used in agriculture field. Underground water is mainly used to produce electrolyzed water in realm of agriculture. Because of various ions is included; it has an effect in the pH buffering in making SAcEW. Therefore, the influence of the resource water's quality on the bactericidal effect of Strong Acid Electrolyzed Water (SAcEW) was studied. The water used as raw material was adjusted to mimic the quality of Japanese ground water in terms of alkalinity by the use of NaHCO3. In this paper, the correlation between the concentration of carbonate ions and pH of SAcEW was examined, and it was in confirmed this study that when the content of the carbonate ion exceeds 68mg/L, the pH of generated SAcEW exceeds regulated upper bound (pH 2.7). The pH rose to 3.3 when the resource water's carbonate ion concentration was raised to 150mg/L, the quality which is similar to the water quality of resource water used in Japan and the results were compared with that of pure water that was confirmed pH 2.5. At the same concentration of available chlorine, SAcEW with pH 3.3 showed faster sterilization speed on E. coli. than at pH 2.7. Therefore, the authors suggest that pH changes from the legal value (pH 2.5±0.2) to pH 3.3 resulting from the use of carbonate ion included water such as underground water would not affect the sterilization speed of SAcEW on E. coli.View full abstractDownload PDF (2225K)
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