Masami Ueno

A measurement of basic mechanical quantities of off-the-road traveling performance☆

Abstract A new test apparatus was developed for the precise measurement of mechanical properties related to the traveling performance of off-road vehicles. In particular the apparatus is capable of performing the experiment under the condition of constant contact load between the wheel and the soil, which most of the existing apparatus do not fulfill satisfactorily, and of measuring the displacement of soil particles beneath the wheel. The test results obtained by the apparatus for a rigid wheel on sand are discussed with some mechanical interpretations.

PRESSURE SHOCKWAVES TO ENHANCE OIL EXTRACTION FROM JATROPHA CURCAS L

ABSTRACT Kinetic data regarding the intensity of maceration and subsequent pretreatment with pressure shockwaves (50 MPa to 60 MPa) are described in detail and evaluated statistically. Mass balances as well as the study on liquid environment are reported, allowing further process optimization according to financial aspects. It was verified on a laboratory scale by Soxhlet apparatus that oil extraction over 94% may be reached. Achieving such a high level of disintegration opens wide options for application of hydrolysis in order to break apart the remaining lignocellulose cell walls and access the last oil remaining in the vacuoles.

Commercial-scale utilization of greenhouse residues

Development of techniques utilizing waste without any additional energy or rare catalysts is a starting point for becoming sustainable. In the present work, the complex utilization of greenhouse residues was studied on a commercial scale. Only the energy produced by the process (8%) was used to run the technology, thanks to multilevel heat recuperation and high methane yields (over 340 m3 volatile solid t−1). Manifestations of labile carbon in relation to available nitrogen, methane yields, and the formation of inhibitors were investigated in detail. The results sweep away many false beliefs about the ratios of carbon to nitrogen and highlight the role of the availability of carbon in phytomass utilization.

The use of underwater high-voltage discharges to improve the efficiency of Jatropha curcas L. biodiesel production.

Underwater high‐voltage discharges (3.5 kV) resulting in 4.9 kJ shock waves (50–60 MPa) were studied at the laboratory scale as a Jatropha curcas L. seed disintegration method. Grinding and macerating in an excess of methanol (3.5:1) was advantageous because methanol acts both as a liquid carrier for the pressure shock waves and as a solvent that increases the efficiency of oil extraction while remaining usable for esterification. The influence of the number of shock waves and the intensity of methanol maceration on the heat values of the pressed cake are stated in detail. Soxhlet extraction demonstrated that a greater than 94% oil extraction was achieved. The increased disintegration of vacuoles rich in oil was documented by surface area analysis, mineralization kinetics analysis, and electron microscopy. The working volumes were small, and the proportion of energy inadequate compared to the yields released; however, much can be improved by upgrading the process.

Automated Quality Evaluation System for Net and Gross Sugarcane Samples Using near Infrared Spectroscopy

Sugar content is the most important index of sugarcane quality in the payment system. A quality evaluation technique for shredded sugarcane was investigated using an automatic and high-speed near infrared (NIR) spectroscopy system. In this study, net and gross canes were tested in order to assess the potential for labour saving and cost reduction by the NIR measurement. NIR reflectance spectra ranging from 1100 nm to 2498 nm were collected to evaluate the cane quality of the shredded cane. A calibration equation for the pol in cane (PIC) of net cane was developed using a modified partial least squares (MPLS) regression. The accuracy of the PIC calibration for net cane was satisfactory with standard errors of prediction (SEP) of 0.21% and a bias of −0.06% in the range 1100–1848 nm wavelength. To eliminate the trash removal, a PIC calibration for gross cane was also examined. Results of the PIC calibration in the 1100–1848 nm wavelength range showed the highest accuracy (SEP=0.46%, bias=0.01%), although the accuracy for gross cane was lower than that for net cane. The NIR instrument could be used as an evaluation tool for the quality of net and gross sugarcane in a practical payment system.

Precise measurement of soil deformation and fluctuation in drawbar pull for steel and rubber-coated rigid wheels

The travelling performance of rigid wheels on sand stratum is measured using two kinds of surface material, i.e. steel and steel coated with rubber. A new method for measuring the displacement of soil beneath the wheel has been developed using small polyester film markers. The trajectories of soil particles beneath the wheels are approximated by an exponential function and the fluctuations in the drawbar pull are represented by a sinusoidal function. The amplitude and basic wavelength of the fluctuation in the drawbar pull are discussed for both types of wheels.

A System for the Measurement of Vertical Gradients of CO2, H2O and Air Temperature within and above the Canopy of Plant

Absract This technical report describes a gradient system for characterizing the vertical gradients of CO2, H2O, and air temperature within and above the canopy of plants. The system is low in cost and easy to use. The instruments were fitted and placed in one box with a total weight of about 10 kg. The box can be carried and moved from one site to another. The features of this apparatus are high frequency sampling cycle as short as 1 min per cycle for all six measurement levels and fast response gas analyzer for measurement as short as 10s per level. Two exhaust pumps, one sampling pump, six 3-way solenoid valves, and flow meter were used to insure simultaneous flow rate of air in all tubes from all measurement levels. This system transfers data from the data-logger directly to the add-in Spreadsheet of Microsoft Excel by using an Ethernet cable to automatically convert digital data to scientific units in less time. This system also allows the use of multiple micro-environmental sensors that can be sampled at the same time. It is useful not only for agricultural ecosystems but is also adequately sensitive and rapidly responds to the gas analyzer with a modifiable flow rate meter for use in forest ecosystems. This system also has potential for use in the measurement of CO2, H2O, associated environmental elements, and CO2 storage flux within the canopy of plant, and other processes including a CO2 sink and source.

Effects of Potassium Chloride and Potassium Sulfate on Sucrose Concentration in Sugarcane Juice Under Pot Conditions

Sugarcane is generally fertilized with potassium chloride (KCl). It was reported in Okinawa, Japan, that potassium (K) in sugarcane juice has a negative effect on juice sucrose concentration. However, in some experiments, increasing K levels with potassium sulfate (K2SO4) did not reduce sucrose concentration. We hypothesized that sugarcane quality is affected not only by K but also by other components of K fertilizers, such as Cl− and SO42−. To test this hypothesis, two pot experiments were performed using different K levels supplied by KCl and K2SO4. Juice K+ and Cl− concentrations markedly increased with K levels irrespective of K type; however, there was little effect of the treatments on SO42− concentration. In the first experiment, as K levels increased, both KCl and K2SO4 application tended to increase sucrose concentration in August samples. In later periods, however, the relationships completely changed based on the K type: sucrose concentration tended to be reduced by KCl application but increased by K2SO4 application. Similar results were obtained in the second experiment, which resulted in lower sucrose concentration with higher levels of KCl; however, there was no negative effect of K2SO4 treatment. These results suggest that Cl− is the primary factor in sucrose reduction. K+ concentration strongly affected Cl− concentration in all K types; however, the rate of increase was lower when only K2SO4 was provided, thereby indicating that it is possible to lower Cl− concentration by K2SO4 application. This measure could lead to quality improvement.

Effects of duration and combination of drought and flood conditions on leaf photosynthesis, growth and sugar content in sugarcane

Abstract Global climate change will result in extreme environments, such as droughts and floods. We investigated the individual and combined effects of droughts and floods of varying duration on sugarcane (Saccharum spp.) growth using a pot experiment under glasshouse conditions with the following six treatments: drought for 15 d, prolonged drought for 30 d, flood for 15 d, prolonged flood for 30 d, short flood followed by prolonged drought, and prolonged flood followed by prolonged drought. Plants that were subjected to drought conditions, including drought after a flood, had reduced CO2 assimilation (through stomatal closure) and leaf areas, whereas flood conditions showed no effect. During flooding, some roots died, and adventitious roots with well-developed aerenchyma appeared from the submerged nodes. At the time of harvest, there were no significant differences in stem fresh weight, sucrose content, or sugar yield between the treatments. However, ion content analysis revealed that flood conditions caused an accumulation of sodium in the bottom of stems and adventitious roots. Therefore, under flood conditions, plants may develop adventitious roots, which may offset the negative effects of root death, helping them to maintain their growth and yield.

Direct sugar content analysis for whole stalk sugarcane using a portable near infrared instrument

Cane quality at the farm is important information for both farmers and millers when evaluating cane maturity and determining harvest schedules. We investigated the non-destructive measurement of the sugar content of cane stalks using a portable near infrared (NIR) instrument. A commercially available portable NIR instrument was modified for use in transmittance mode and employed to quantify Pol levels in cane stalks. Calibration models using a partial least squares regression analysis were developed for predicting Pol values from the juice and the cane sample spectra (600–1100 nm). Results of these calibrations, root mean square error of prediction for juice and cane samples, were 1.0% and 1.1% Pol, respectively. Based on the results of this study, the developed measurement method appears to be useful for monitoring cane quality and the planning of harvest schedules.