The utilization of the biogas as the fuel for the internal combustion engine has been studied mainly on gasoline engine. But it seems effective to apply the biogas to the diesel engine which has economical fuel performance and good durability. In this paper, the replacement percentage of gas oil by the biogas was investigated. Also the waste edible oil methyl ester (WME) was used instead of gas oil and the running performance with quasi-biogas was investigated. The quasi-biogas composed by methane gas and carbon dioxide was applied to small type diesel engine. The rotational velocity, the amount of supplied gas volume, the power output and the ingredient of exhaust gas was measured. With the results obtained in the experiments, the performance of the engine was similar between the gas oil and WME. The quasi-biogas was supplied and up to 77 percent of the gas oil and up to 69 percent of WME was replaced.

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The way of using woody biomass varies in burning, producing ethanol, gasification and so on. Some researches have been made for cultivating and producing short rotation trees as an energy source. Woody biomass such as willow or hybrid poplar is grown in European and North American countries. In that area, sugarcane harvester is used for harvesting woody biomass production. While in the south-west islands of Japan, sugarcane is grown as one of the main crops and many harvesters are used. Also, considerable area is expected for woody biomass production. There should be big potential to grow short rotation trees for energy source in that area under the subtropical climate. In this study, the production possibility of woody biomass in south-west islands of Japan is discussed. For testing the adjustability with the sugarcane production, the cutting resistances of some selected species were measured using the cutting knife of the sugarcane harvester.

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We investigated the influence of the kinds of fertilizers on the concentrations of polyphenols in the tea shoots. The contents of four kinds of catechins such as (-)-epigallocatechin 3-O-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin 3-O-gallate (ECG) and (-)-epicatechin (EC) decreased when the applied amount of organic fertilizer and chemical fertilizer was increased. The concentrations of EGC and EC increased during the first flush developing period. However the concentrations of EGCG and ECG were maximal just before the first harvest period. The concentration of strictinin decreased during the first flush period and was very low during the summer harvest period. It was suggested that gallic acid was found prior to the formation of an ester with the flavan-3-ol at 3-position of EGCG and ECG, whereas the formation of strictinin was relatively decreased probably due to the lack of gallic acid to combine with D-glucose.

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For the simultaneous removal of phosphorus and nitrate from drainage water, we explored a method that involves the use of "filtration cake," which is composed of industrial waste from a filtration plant. Nitrate removal was possible by denitrification under anaerobic conditions, using a filtration cake containing rice straw. Decreasing the soluble oxygen concentration to approximately 1.0 mg/L was desirable for nitrification and placing the cake at the influx of the filtration equipment was noted to be most effective. The filtration cake supplemented with 0.1% rice straw was insufficient for denitrification and could not remove nitrate completely. When the filtration cake was used rather liberally, a large amount of nitrate was eluted into the drainage water, and decreasing its concentration was time-consuming. In all experiments, phosphorus in the drainage water was completely removed soon after starting the treatment.

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It is necessary to elucidate the factors determining sale price formation in the calf market so as to ensure a stable cattle breeding management in the beef industry. This paper examines the causal relationship between calf lineage, breeding days, sale weight, purchaser and calf sale price along with the effect that enhanced breeding management technology has on farm management improvement by means of multivariate statistical analyses. Meaningful results have been found in this study. Firstly, the sale weight continues to be the most important factor influencing sale price. Secondly, the difference in sale price between individual calves is obvious and the difference between farm households is significant according to results of the variance analysis. However, sale weight and change of lineage which are farm household factors explain little of the changes in calf price and most explanation is given by changes in individual calves. Changes in individual calves are associated with the farmer's breeding management technology and reduction of production cost.

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This paper evaluates the use of near infrared (NIR) spectroscopy and chemometrics in determination of chemical oxygen demand (COD) in simple organic solutions. For this purpose sucrose-water, BSA (bovine serum albumin)-water and sucrose-BSA-water matrices were used as standard solutions. The solutions were prepared and the COD determined by using standard methods. The COD ranged from 7.5mg/l to 1397mg/l. NIR of different dilutions were taken and the resulting spectra preprocessed into first derivative (1D) and second derivative (2D) spectra. Calibration models were developed based on multiple linear regression (MLR) and partial least squares regression (PLSR). The best calibration models were as follows: PLSR-2D for sucrose-water matrix (R=0.9618), MLR-Absorbance for BSA-water matrix (R=0.9939), and MLR-Absorbance for sucrose-BSA-water matrix (R=0.8798). It is concluded that NIR and chemometrics has a good potential to be used in determination of COD even in complex matrices like real wastewater.

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This article aims to clarify what consumers are more likely to frequently make a purchase at convenience store. The logistic regression analysis, based on the individual data obtained from the Japanese General Social Survey 2003(JGSS-2003), clearly suggests that consumers fulfilling the following conditions are more likely to do so: 1. They are male, young, in employment, and smokers. 2.They tend to go shopping frequently, and do not mind price. In addition, they are not members of a consumer organization. 3.Compared to several years ago, they take more meals outside their home. 4.They resident in the Hokkaido, Southern Kanto and Kinki regions.

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Symptoms and occurrence time of water spot-like disorder of 'Kiyomi' fruit ('Miyagwa wase' satsuma mandarin [Citrus unshiu Marc.] x 'Trovita' orange [C. sinensis Osbeck]) were investigated. No disorder appeared before December but the injury began to occur in January and gradually increased thereafter. The percentage of disordered fruit was 3% and 10% in January and March, respectively. External water seems to enter rind through structurally weak portions such as cracks at the stem end and fresh mechanical wounds. Since the symptoms were similar to those of water spot injury of 'Natsudaidai' (C. natsudaidai Hayata) fruit, this disorder can also be designated as water spot injury of 'Kiyomi' fruit.

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This study was carried out to clarify the suitable planting system for getting high quality of cut flowers of Lathyrus latifolius L. Plants of 'Pink Pearl' were planted at distance of 15-, 30-, 60- or 90cm in single row. Moreover, plants were planted on single, double or triple row at 30cm intrarow space. When plants were trimmed leaving four shoots and were planted at 30cm distance in single row, cut flowers with sufficient stem length were harvested.

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