In this research, we have proposed the best processing system the BAS (Best Available System) on both sides of the environment and the economy to us by using LCA (Life Cycle Assessment) and LCC (Life Cycle Costing) for waste management. To propose BAS, the municipal waste evaluation software has been developed in our laboratory. We objectively evaluated the technology as an example of the next generation stoker-type furnace and the digestive equipment of sewage sludge. And we evaluated various ranges of the evaluation, We considered the influence on the evaluation result and the meaning of the evaluation result.

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Teshima waste treatment project has been done as a solution of the industrial waste illegal disposal problem happening in Teshima-island, Kagawa Prefecture since 2003. The role of the watch of the project is requested by the resident living in Teshima-island and Naoshima-island. On the other hand, disclosing useful relevant information for the understanding this project is needed in Kagawa Prefecture who is the entrepreneur. Both of information matched to the progress of the project .co-creation system is thought to be necessary by such correspondence. We have aimed to practice what we can do as an engineer. The goal of our study is to prevention illegal dumping and to accumulate data about teshima waste treatment project. In this report, we show the result of Life Cycle Assessment (LCA) of Teshima waste treatment project was evaluated.

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The aim of our study is to propose manufacturers and users have to do for building a sustainable zero-waste economy/society through quantification of the design for environment, DfE. For a background problem of global warming and depletion of natural resources, it is required to reduce the environmental impacts of the products and services life cycle and to develop the method for quantifying the environmental impacts. Following such a demand, the Eco-Efficiency Potential Assessment, E2-PA which could solve problems in existing LCA, is developed. The feature of E2-PA is to be able to assess the environmental impacts only by the data on the design phase of products and services. Therefore the designer can consider the life cycle including used on the design phase. In this paper, we pay attention to home appliances and ICT devices. Then, we analyze the way of reducing the environmental load about them through a comparison between the environmental load in use and in manufacturing.

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A number of accidents are happening in waste disposal and recycling facilities. Diversity of waste and advancement of disposal and recyclingtechnologies are considered one of the reasons. Then, we construct and analyze database called ATHDB-all. It contains accidents, troubles and the Hiyarihattocases that happened in Japan. The goal of our study is to construct safety and soundsystem in waste disposal and recycling facilities. We upgradethe collecting information tool by ICT(information communication technology)and use these continually in two individual facilities. To developthe safety education systemby APT(Accident Prevention Training tool) with 3D-VR(Virtual Reality) technique, we make software that can analyze database which have individual facilities' accident informationautomatically.

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The characteristics of greenhouse gas emissions from small wastewater treatment plants (WWTPs) in Japan were studied using life cycle assessment methodology within the confine of the operation phase of the WWTPs. As the oxidation ditch process (OD) has been adopted mostly in small scale wastewater treatment plants in Japan, our study focusing on WWTPs using OD process as an water treatment method. The ratios of greenhouse gas emission to total treated wastewater of WWTPs declined over the first five-year.

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Sterilization device using an atmospheric pressure discharge has been expected as a next-generation sterilization method due to easy handling, low cost and safety. In the present study, we generated plasmas in air and water vapor. The sterilization of spores of Geobacillus stearothermophilus was completed in the air plasma for 40 min-discharge and the water vapor plasma for 180 min-discharge, respectrively. In the case of air plasma, NOx were considered as one of sterilization factors since NOx were observed by a spectrum analysis. This result implies that sterilization in the air plasma at atmospheric pressure has a good performance as a sterilization device.

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Ultra-high pressure underwater shock wave was applied to treatment microbe. The imploding detonation of propane-oxygen mixture was used to generate underwater shock wave in sample holder. We investigated imploding detonation wave in approximately cone-shaped combustion chamber having maximum inner diameter of 60 mm. As microbe of the treatment experiments, Microcystis sp. and Anemia salina's eggs were used. As a result, we could completely treatment the Microcystis sp. by more than 3 times treatments of the underwater shock wave that maximum pressure was about 100 MPa. On the other hand, the experimental result using Anemia salina's eggs showed that hatchability was less than 1% at over 2 times treatments of about 100MPa under water shock wave.

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The author reports the development of the new chemical water treatment technology using the aqueous of stabilization hypochlorous acid. This stabilization solution is prepared by the low environmental loading manufacturing equipment for very precise fluid control using diffusion phenomena. It is prepared from dilute hydrochloric acid and aqueous solution of sodium hypochlorite without the electrolysis. The work environment of the preparation process is very good, since the preparative procedure without using or generation of the chlorine. The prepared aqueous solution is high precise continuously prepared with optionally designated for the available chlorine concentration; 10 ppm < [available Cl] < 200 ppm, and the hydrogen ion exponent (the pH value; 5.0 < pH < 6.8). In addition, the aqueous solution is very long life, and it is possible to storage and/or prevails. This functional water is a solution presenting slightly acidic or neutrality without having the corrosiveness, since the hydrochloric acid is not contained in forming solution. Since it has the powerful oxidizability, this solution manifests very powerful pasteurization effect and deodorizing effect. This aqueous solution is used in order to deal with water supply, intermediate process water, and wastewater. It is widely applied in medicine, food processing, agriculture, livestock industry, fisheries field and so on. In addition, the author also reports applications of this technology for prevention of epidemics countermeasure.

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The environmental regulation tends to become strict rapidly, and the further highly performance of DPF is demanded. Generally, the square cell design of DPF is worldwide standard. In recent years, DPFs with some another cell design have been realized by the improvement of processing technology. These DPFs have been developed for higher Ash capacity and lower pressure loss. In this study, we compared two DPFs performances between hexagonal cell and traditional square cell. We measured particle number concentration by EEPS to obtain filtration efficiency on early filtration stage; and we also measured pressure drop during soot loading at engine test bench. Results show that, the soot leakage on early filtration stage reduced rapidly with hexagonal cell. Backpressure during soot loading with hexagonal cell is lower than that of traditional square cell.

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Diesel Exhaust Particles (DEPs) are the problem of air pollution in high concentration the closing space such as long-distance tunnels of highway. Electrostatic precipitators (ESPs) are installed in a tunnel to collect particulates that principally involve DEP. They are suitable for decontaminating polluted gases and improving the visibility index in road tunnels, thereby saving drivers and improving the air environment around the tunnels. In this study, the underlying data of ESP performance was extracted in condition of high gas flow velocity. The gas flow velocity was in the range of 10 to 25 m/s. The experimental ESP was two'stage'type which composed of a prechager, followed by the collection section. The high voltage electrode in the charging section was sawtooth type. The collection efficiency for experiment and the simulation were compared. The constitution of the ESP units to collection efficiency was considered.

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The author investigates adsorption and desorption process of NOx as an aftertreatment system for diesel engine exhaust gas. This report suggests the possibility of the system that can reduce both the NOx generation and fuel consumption of diesel engine. In this study, the mechanism of NOx reduction is studied qualitatively through the extended-Zeldovich mechanism.

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The intense shock waves were applied to the CO_2 decomposition. High temperature and high pressure exhaust gas, produced by the propane-oxygen detonation, was used to generate intense shock waves in a low pressure chamber of 100mm inner diameter. The experimental apparatus was composed of pre-combustion chamber, imploding chamber, and shock tube which consists of a high pressure chamber of 2020mm in length and a low pressure chamber 4250mm in length. The experimental results show that the volume ratio CO/CO_2 increases as the temperature increases. The volume ratio CO/CO_2 was about 0.27 at 3800K using intense shock waves. The volume ratio CO/CO_2 was about 0.64 at 3500K using iron particles of rough grain.

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A near-IR laser based spectrometer for continuous measurement of stable carbon isotopes in CO_2 has been developed. ^<12>CO_2 and ^<13>CO_2 are detected with wavelength modulation spectroscopy and a Herriott-type multi-pass cell with a optical path length of 29.9 m using a distributed feedback laser diode in the 2-μm wavelength region. To measure the isotope ratio precisely, the influence of pressure and temperature variation in d^<13>C was evaluated. The limit of detection for our system was 16 ± 1 ppbv. The precision in the determination of δ^<13>C was 0.1 ‰ for 120 seconds signal integration time at ambient concentration levels. We demonstrate that our system enables automated continuous measurements of δ^<13>C of CO_2 in ambient air without any complex operation by users.

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The authors have been developed both of the electro-magnetic heat absorption technique and electro-magnetic resonance combustion technique for realization of high energy saving and low CO_2 emission. From several kinds of verification tests, we may say that a specific wave number at the regime of far infrared rays has both abilities to promote the combustion process and to increase the amount of heat transfer to working fluids from combustion gas. The principle is very useful to achieve the high energy saving and low emission of CO_2 for fossil fuel combustion.

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An atmospheric plasma discharge was produced between a platinum pin electrode and the surface of water. The thermal flow field of the cold atmospheric plasma in air and water was measured experimentally and analyzed computationally. A gas flow with a velocity of around 15 m/s was shown to be generated toward the water surface by the discharge. This air flow induced a circulating flow in the water from the discharge point at the water surface due to friction. These results were also predicted computationally.

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It is important to track the behavior of bottom sediment which does harm to water environment. The purpose of this study is to predict a series of natural phenomena, namely, natural wind creates currents in the water, and, in turn, stirs up the bottom sediment. In our numerical simulations transport of fluid (air and water) and mass (sediment) are examined simultaneously. From the numerical results influences of inflow (natural wind) velocity on the stirred bottom sediment was evaluated. It is discovered that bottom sediment moves more broadly and actively in larger inflow velocity. It is also revealed that oscillate flow occurs in the water. This may cause the sediment resuspension.

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This study aims to clarify the cedar pollen transportation by suspension and saltation and to confirm the validity of the prediction method. For this purpose the followings are done: (1) The terminal velocity of Japanese cedar pollen is measured and the test particle is selected. (2) The suspension and saltation behavior of the test particle is observed and measured by the optical measurement methods: path line image analysis and particle tracking velocimetry. (3) The suspension and saltation behavior is also numerically calculated by Euler-Euler method and Lagrangian particle tracking method respectively. These methods can predict the suspension and saltation behavior.

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The relationship between local circulation and surface air temperature during mid-summer in Osaka plane was investigated. The pattern of local circulation was categorized according to the wind direction, and the frequency of each category was estimated from surface observation data. As an index of sea breeze cooling, the amount of sensible heat advection was calculated by using a meteorological model.

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A calculation method is considered that it is able to simulate atmospheric dispersion of ship exhaust. This calculation method is structured the following these elements: (1) estimation model of two dimensional wind based on SIMPLE (Semi-Implicit Method for Pressure-Linked Equation) with observed data, (2) calculation formula for amount of exhaust NOx based on total volume control manual and (3) discretized advection-diffusion equation based on Cell Automaton method. This simulation runs that diffusion of ship exhaust that sail inside Osaka Bay by using this calculation code which is combined these elements. The result confirms that ships move shipping route as time progresses and ship exhaust diffuse downwind while convect one. It is, consequently, exposed that this calculation method is available diffusion simulation of ship exhaust.

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The Annex VI on "Regulations for the Prevention of Air Pollution from Ships" in MARPOL 73/78 was revised to progressively reduce air pollutant emissions. The revised Annex VI went into effect in July 2010. This study estimated changes in air pollutant emissions from ship after the effect of the revised Annex VI and impact of the change in emission on air quality. For the estimate of change in ship emission from the present to 2050 in Japan, following assumptions were applied: the life of ship is 35 years; shipping tonnage is constant. The total amounts of NO_x and SO_x emission in the study region are expected to be decreased by 17.5% and 24.3% between the present and 2050, respectively. The WRF/CMAQ modeling system was utilized to predict the impact of the ship emission regulation on air quality in Kinki area. The results show that combination of ship emission regulation and land base VOCs regulation is more effective for the decreases of air pollutant concentrations in larger area.

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Fundamental characteristics of N_2O decomposition and formation by atmospheric non-equilibrium plasma were investigated under room temperature without catalysts. A pulsed dielectric barrier discharge (DBD) with a one-cycle sinusoidal-wave power source was employed. In N_2O-N_2 system, an N_2O concentration of 40 ppm was completely decomposed at an applied voltage of 18 kV. In N_2O-O_2-N_2 system, N_2O was produced by elemental reaction in the DBD reactor by contribution of O and N radicals. O_2 concentration was determined to decompose 40 ppm N_2O by the DBD reactor.

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A unique SNCR system by excited ammonia injection using an intermittent dielectric barrier discharge (DBD) has been developed to remove NOx from an incinerator. However, the NOx reduction mechanisms are not elucidated so far.. In this paper, nitric oxides formation was investigated in excited NH_3-O_2-N_2 system. Hydrogen concentrations at the plasma reactor and NOx concentrations at the reactor exit were measured to characterize chemical species generated by DBD. Hydrogen concentrations were increased with an increase of the applied voltage and residence time of NH_3/Ar gas mixture in the plasma reactor. In oxidation of excited NH_3, NOx was generated above temperature of 600℃. Behavior of NOx formation in experiments was compared with calculation results by elementary reaction analysis based on Miller & Bowman mechanism.

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To broaden and lower the narrow temperature window of the selective non catalytic reduction (SNCR) of nitric oxide (NO), the use of activated ammonia as the reduction agent was examined A xenon excimer lamp emitting a wavelength of 172 nm (i.e., vacuum ultraviolet; VUV) was employed as the excitation source for molecular ammonia. The effects of reaction temperatures, oxygen concentrations, and NH_3/NO molar ratios (MRs) on NO removal were investigated in a lab-scale plug flow reactor. Temperatures ranged from 500℃ to 850℃. A temperature window enlargement of 150℃ was achieved at the lower boundary of the temperature window. Above 600℃, NO removal was effected by injection of activated ammonia, while around 750℃, conventional SNCR by injection of molecular ammonia was effective. An approximate 80% NO removal was attained at 700℃ with an MR=2.0 and 8.3% O_2.

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The authors realize a new prototype of plasma-assisted environmental protection aftertreatment system using atmospheric-pressure nonthermal plasma combine processes for super clean diesel engines. This system does not use any rare or precious metal catalysts and harmful ammonia or urea solution. A NOx aftertreatment system, using nonthermal plasma (NTP) reduction and exhaust gas components recirculation, is investigated. A pilot-scale system is applied to a stationary diesel engine using A type of heavy oil fuel. In this system, NOx is first removed by adsorption, and subsequently, the adsorbent is regenerated by thermal desorption. The desorbed high-concentration NOx is reduced by using nitrogen NTP with low flow rate. Moreover, NOx re-circulated into the engine intake reduces NOx emission. In the present experiments, a very high system energy efficiency of 437 g (NO_2)/kWh is achieved in the NOx reduction test. The developed system demonstrates excellent energy efficiencies to meet the most recent international regulation of marine diesel engine exhaust gas.

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The effect of a plasma feedstock gas on the composition of combustion products in plasma-assisted combustion was investigated by a spectroscopic measurement of the ethylene (C_2H_4) flame ignited and held by a plasma jet (PJ). Spectra of CH, CN and C_2 were detected in emissions from the flame ignited by N_2 PJ. On the other hand, only CH spectrum was detected in emission of the flame ignited by O_2 PJ. The decrease in the CN emission downstream was much faster than those in CH and C_2 emissions. In the case of N_2 PJ, an increase in the electric power to the PJ torch decreased the flame length.

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To decrease the power consumption of air-conditioning in the data centers, a packaged air-conditioner that contained the pump cycle was developed. The new air-conditioner has improved COP when outdoor temperature degree is especially low. In this report, the performance at the pump cycle was evaluated with a real machine of the test site. As a result of the verification, the stability of driving at the pump cycle was confirmed. In addition, it was shown the relation between outdoor temperature degree and total COP, and high driving efficiency at the low outdoor temperature degree.

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In this report, the performance of the double-skin facades is studied. The comfort and energy efficiency in the building where double-skin facades is introduced are investigated. It is confirmed that window surface temperature, vertical room temperature differences, PMV near window, the maximum in air-condition load, and the window shade installation position achieve the targeted value.

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For the power saving of the data center air-conditioning systems, not only efficiency as for the air-conditioning machine but also the method of operating the server room becomes important We executed the measurement verification of the operation improvement measures in the server room. One measure is the IT device suction exhaust current of air separation, the other is making return air proper. The effect of an environmental improvement and the effect of the power saving of these measures were clarified. Moreover, the note to maximize the effect of measures was considered.

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Multi-split type air-conditioning systems for buildings that have multiple indoor units require the system performance analysis under various operating conditions for optimization of their design and operation. In this paper, a cycle simulation model for multi-split type air-conditioning systems is developed because the system performance analysis by experimental approaches takes a lot of time and energy. The simulation model is based on a module partitioning approach so that the model can be easily extended to various kinds of system configurations and refrigerants. Moreover, the cycle performance of a multi-split type air-conditioning system that has two indoor units is analyzed by using this model. The result reveals the cycle performance under a typical operating condition where the inlet air temperatures to the two indoor units are different.

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Recent years, global environmental problems have become aggravated, and various energy-saving functions and methods been introduced in vending machines. However, it is reported that useless energy is consumed because the amount of power consumption changes greatly by the installation environment in actual operation. We aim to improve over concentration of vending machines by considering demands, conveniences, and environmental impact of vending machines. In this study, our team cooperates with Pacifico Yokohama and vending machine companies. We tried to make reduction of power consumption in Pacifico Yokohama by using our system of Conservation of energy setting at vending machine.

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In this study, we estimated the energy saving performance of Photovoltaic Thermal Hybrid System (PVT system) by the computer simulation. PVT system is a device that combines solar thermal collector and photovoltaic cell. We inputted 12 houses data into our simulation. These data are actual general houses data in a year. This simulation results show that electrical efficiency and thermal efficiency of PVT system depend by water flow. PVT system has three type of PV which are crystalline, multicrystalline and amorphous silicon. The efficiency of PVT system of crystalline silicon is higher than the others. Rate of primary energy reduction of PVT system is better than that of PV cell, solar water heater or PV cell (3m^2) + solar water heater (3m^2). Therefore PVT system has the better performance of energy saving.

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Recently, global warming has become a serious problem. For Japan in the world's highest level is already energy efficient, the shift from fossil fuels account for the majority of energy is required for promoting greater energy non-fossil. Then, this study is intended to examine possible measures to aggressively promote new energy. Although solar thermal energy is one of the most effective green technology to reduce GHG emission today, number of installation in Japan has been declining as well as its market shrinking causing withdrawal of manufacturer from the division. On the other hand, installation of such equipments in abroad has been growing which tightened competition resulting in improvements of cost performance and technology, and eventually price-reduction. Thus, we have completed verification test of foreign-made solar heat panels and examined its usage, economic impact and influence of installation in order to stimulate domestic market of solar heat panel.

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Solar energy use air-conditioning system has been attracting great attention from the view point of global wanning problem. In this paper, the performance of a solar-assisted absorption chiller heater of 352 kilowatt refrigeration capacity has been examined experimentally through a long series of proof examination of 17 months. Also, the analytical model of solar collector subsystem has been developed and the temperature changes at the collector outlet were calculated in order to investigate the performance theoretically. Solar radiation irradiance, temperatures at inlet and outlet of circulation water in three types of solar collector, collecting heat amount by the solar energy and town gas consumption rate were measured continuously every ten minute. From these measured data, both of the solar collector performances and the absorption chiller heater performance were calculated and the performance properties of the system against the solar radiation were revealed. Consequently, the amount of town gas consumption of the absorption chiller heater has been decreased about 13 percent through air-conditioning period. Also different characteristics of three types of solar collectors to the solar radiation were revealed quantitatively.

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The energy saving characteristic is investigated for a gas engine cogeneration system combined with a photovoltaic array and a gas engine heat pump with power generation or a gas-fired absorption chiller heater with input of exhaust heat, when it is installed into a hospital as an example of commercial buildings. The on-off status and load of each piece of equipment are determined to minimize the primary energy consumption of electricity and natural gas purchased from utility companies. This optimization problem is formulated as a mixed-integer linear programming one and is solved using a commercially available solver. A numerical study shows that the gas engine cogeneration system is superior to a conventional system in the energy saving characteristic: the energy saving rate of the system with the gas engine heat pump with power generation is about 11%, and that of the system with the gas-fired absorption chiller heater with input of exhaust heat is about 8%.

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An efficient configuration method of a biogas-fuelled cogeneration system (CGS) in a sewage treatment center was investigated in this study. The efficient configuration was clarified by classifying a relationship between exhaust heat recovery efficiency (η_<ehr>) of the micro gas turbine COS, and the ratio of average heat demand to average biogas production of the facility (Q_<h.d/Q_<b.p>). It was found that the CGS can cover the total heat demand of the facility by only using biogas produced in any conditions, but on the point of view of reduction of unutilized biogas efficiency, biogas energy recovery efficiency and reduction of electrical power demand efficiency, the most efficient CGS was obtained under Q_<h.d>/Q_<b.p> 〓 η_<ehr> condition. If a CGS with lower η_<ehr> such as a fuel cell is used under Q_<h.d/Q_<b.p> < η_<ehr> condition, or a CGS with higher η_<ehr> such as a steam turbine is used under Q_<h.d/Q_<b.p> < η_<ehr> condition, more efficient system can be obtained. On the other hand, if η_<ehr> cannot be conformed with the Q_<h.d/Q_<b.p> value of the facility, more efficient energy system can be obtained if other heat supplier equipment such as a heat pump is used under the Q_<h.d/Q_<b.p> > η_<ehr> condition, and other biogas or heat utilization pathways are used under the Q_<h.d/Q_<b.p> < η_<ehr> condition.

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Free cooling system is a system which manufactures the chilled water for air-conditioning or production equipment when outdoor air temperature (wet bulb temperature) is comparatively low. Since cold heat can be made without using a freezer if conditions suit, the large energy-saving effect is expectable. In this paper, we calculated heat load of a modeled office building and analyzed energy consumption and carbon dioxide emission with using gas absorption chillers and free cooling system.

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Authors have proposed application of ice slurry to a cold storage of foods for widely using the ice slurry. Thus, in order to form new ice slurry for cold storage of foods, a trehalose with the effect expected to suppress ice crystal growth was used. The trehalose is a kind of a food additive. In this paper, "harvest method" was adopted to form the ice slurry. And freezing characteristics of trehalose solution were investigated based on a scraping force of ice growing on a carbon steel surface and observation results for behaviors of scraped ice, varying amounts of formed ice and supercooling degrees. Moreover, a feature for freezing characteristics of the trehalose solution was also clarified by comparing scraping force in the case of the trehalose solution with that of the ethylene-glycol solution.

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The authors, in order to investigate the basic characteristics of an autorotating plate in uniform mainstream, which has a potential for new windmills and waterwheels with very simple structures in addition to mixers/difrusers. The present study concerns subsonic wind-tunnel experiments, focusing on both the effects of an aspect ratio AR and a tip-speed ratio Ω^* upon the tumbling of a flat plate with a low depth-to-width ratio λ = 0.02 - 0.08. The authors carry out flow visualisations and measurements using a hot-wire anemometer and a torque meter together with the synchronised measurements of a plate's attack angle α for the analyses with a phase-averaging technique. As a results, there are two flow modes I and II. In addition, the authors reveal the basic features of each mode, on the basis of instantaneous velocity profiles at each α, flow visualisations, wake deviations, momentum deficits and torque. These give us more useful information for efficient renewable-energy resources.

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Geothermal energy resources are abundant in Japan, and are expected to actively use. But most of the geothermal resources are liquid dominated and have been delayed development. The porpouse of this work is effective energy conversion from geothermal resources. In order to apply the helical screw expander to the total flow geothermal system, influence of the quality at the expansion process are investigated. Then, the practical relationship between the built in pressure ratio and the expansion ratio at the adequate expansion process are obtained. This expression facilitates the computation of the theoretical work and the theoretical efficiency and is useful for understanding the performance of the screw expander.

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Wind energy has potential and usefulness as natural energy, and can be harvested from wide range of windy area. We have developed a flexible piezoelectric device (FPED) composed of polyvinylidene fluoride (PVDF) and functional polymers. The characteristics of the FPED are thin layer, light and flexible. Therefore, both a force caused by breeze and flow energy with various frequency spectrums can be used effectively using the FPED. In this study, we make clear electrical characteristics of the FPED and availability of an attached bluff body in uniform flow. Moreover, we validated improvement of electrical efficiency due to the structural changed FPED by conducting a vibration test.

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Stored winter cold in snow and ice is used for cooling during the summer, one alternative electricity use. In Japan, this snow and ice use system is employed in about 140 buildings. Of this, 117 buildings are using snow, and 14 buildings are using ice. Collecting snow or ice only for cooling is too much expensive. Therefore, ice-using systems need making ice artificially at cold climate. In Sweden, for artificial ice making, the snow gun is used at very cold climate. In Japan, average temperature is relatively high, the two-fluid nozzle has low coefficient of performance and high cost problems. So, we tested for efficiency of making ice using one-fluid nozzle at indoor and outdoor. Ice production rate was 78% at outdoor -6 centigrade. In Hokkaido, initial costs estimation of one-fluid nozzle is lower than chiller.

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In this study, the photosynthetic microorganism that was able to do the production life of energy by using sunlight as well as the plant was researched. The photosynthetic microorganism is a kind of the most primitive bacillus in the living thing that does photosynthesis, and hydrogen is produced in the reactive process according to the kind. However, because carbon dioxide cannot be reduced by decomposing water by the difference from the plant photosynthesis, an organic compound and the hydrogen sulfide, etc. are used. The hydrogen processing technology that uses such phototropic bacteria is paid to attention as a low environmental impact technology that generates hydrogen from the organic refuse and light energy. However, because the hydrogen generation efficiency is low now, it has not become practical use. Then, we aimed at the efficiency gain of the hydrogen formation by phototropic bacteria. "Rhodopseudomonas Palustris" that was the purple nonsulphur bacterium of phototropic bacteria was used. The relation between the substrate dosage and the amount of the hydrogen generation was verified, and an increase in the amount of the hydrogen generation by the optimization of the substrate dosage and the improvement of the hydrogen generation efficiency, etc. were examined

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The main challenge for biodiesel fuel (BDF) production is the cost reduction in view of the chemicals utilization and energy consumption for a long reaction time and purification processes. Many reactors have been developed to enhance the reaction rate, reduce the chemicals and energy requirements. In this research, a comparison of two mixing technologies were carried out; conventional mechanical mixer and the static mixer. The static mixer has the potential to deliver better rigorous mixing, to the point that it can make the dispersed droplets of methanol in the raw oil smaller and more uniform, which should result in enhancement of the reaction with the possibility of shortening the reaction time associated with BDF production.

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The isobaric heat capacities of liquid ethanol are measured. Our group constructed a flow-calorimeter in 1996 for measuring specific heat-capacity at constant pressure of liquid refrigerants. Moreover, improvement of apparatus is continuously conducted. In 2008, Suzuki reconstructed the apparatus of a flow calorimetry and stable mass flow rate became possible. And isobaric heat capacities of ethanol are measured by using this apparatus. The measurements obtained 8 points at the temperature range from 280 to 320 K and at pressures 500 kPa. And uncertainty for heat capacity is estimated to be from 0.59% to 0.69% .Because we confirmed that the apparatus is able to measure isobaric heat capacities without influence of heat loss and to get the repeatability within the uncertainty, we are sure that our measurements are reliable value. For more careful consideration, we measured two different samples of ethanol under the same conditions. Even after replacing sample, measured value is within the uncertainty. And we also measured isobaric heat capacity of ethanol in lower temperature range. The measurements don't perfectly agree with existing measurements or derived specific-heat-capacity values from existing equation of state developed by Dillon and Penoncello within the uncertainty. We believe our measurements to be much reliable, although we are currently checking the reliability by further measurements.

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The authors research the jet from an asymmetrical two-dimensional nozzle, especially focusing upon the influence of jet's pulsation. Experiments are conducted at a Reynolds number of 6000. The aspect ratio of the nozzle exit is fixed to 300, and the lip length is 0,33h and 5.0h, where h denotes the height of the nozzle exit. Using a hot-wire anemometer, the authors show mean-velocity and turbulence-intensity profiles, comparing the pulsating flow with the steady flow.

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Measurement of thermophysical properties for gases near the saturation state is difficult, so the number of measurements is limited there. For example, specific heat at near saturation is important for designing air-conditioning and refrigeration systems, which is not correctly determined from equations of state. More than 5% difference is possible to exist among plural equations of state in the worst case such as R-143a. In our group, we study on determination of thermophysical properties including thermodynamic and transport properties such as viscosity, thermal conductivity from theoretical method using intermolecular potential model with the same or better uncertainty as that of measurements. We already confirmed to predict accurate thermodynamic properties and viscosity. For CO_2, isobutane and propane, thermodynamic properties and transport properties are predicted and compared with existing experimental results in this report.

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Among the various thermophysical properties, critical temperature and density are the most basic quantities of state. A determination method of these properties is studied, which uses a digital-image processing for the image around the vapor-liquid phase boundary of sample fluid near the critical point. Critical temperature and density can be determined on the basis of quantitative measurements. Conventional method was based on the personal observation of the meniscus. Author improvement is determination of the inner volume of a sample cell, which was measured using liquid normal butane. Using a new method, the following critical parameters were predetermined. Critical temperature of 304.143 K and density of 466.6 kg/m3 were determined with the expanded uncertainties (k=2) of 0.010 K and 1.1 kg/m3, respectively for carbon dioxide. Critical temperature of 407.808 K and density of 223.0 kg/m3 were determined with the expanded uncertainties (k=2) of 0.0094 K and 1.1 kg/m3, respectively for isobutene.

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Depleting of fossil fuel, contamination of atmosphere, traffic congestion, and so on, car life scene of recent years demands of mobility which is able to drive with smallest size of body and fewest energy. Now then, this project will produce "Ultra Light Vehicle" (ULV) which is able to drive with smallest size of body and fewest energy, and consider a method of decreasing environmental load and improvement model of "manufacturing in local and exploiting in local", which model of ULV is able to assembled by local small and medium-sized enterprises, and used effectively in local area. So, this project aim to realization of futurity mobility from community. In addition, aiming to "manufacturing in local and exploiting in local" model of ULV, this project will realize "Multi-PM"ULV, which model is able to choose suitable prime mover for area. Finally , this project consider these things, and aim ULV to spread and use effectively.

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In order to make lower environmental effect of domestic air conditioning system, we propose a new air conditioning system using cooling tower principle for outdoor unit. By performing experiment with a testing system, which is modified by replacing the air-cooled condenser by a water-cooled condenser, we confirmed a possibility to make lower condenser temperature. Moreover, the proposed system's performance is simulated using vapor compression cycle theory at a condition of the common cooling load for existing system. We compared the amount of power consumption with the conventional case. Saving power consumption is possible as outdoor temperature increases and it reaches up to 30% in the summer at temperatures of outdoor between 27 and 37 ℃. Amount of external exergy loss of the air-cooled condenser due to high temperature exhaust heat can reach to about 300 W at outdoor temperature of 37 ℃ and exhaust heat of 1.1 kW, while it is assumed to be nearly zero in case of the new system due to no temperature difference between condenser and the environment. Last but not least, a prototype of new heat exchanger is proposed and tested in summer weather. The results shows that heat-transfer coefficients are at least 4 times higher than the compact-heat-exchanger which is popularly used in air-cooled condenser of conventional air conditioning system.

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