An economic and energy analysis on bio-hydrogen fuel using a gasification process

Recently, in Japan, recycling technologies have been developed using waste biomass material. Waste biomass is traded in the waste materials market between users and a third-party, who receives a fee for processing them. This study is an environmental and economic analysis of a biomass energy system, which can produce hydrogen fuel for fuel cells (purity of 99.99%) as an example of an environmental business model. The experimental apparatus was made based on the moving-bed gasifier by the German company, DM2 Inc., and the hydrogen gas yield was measured. Finally, the economic viability of the future hydrogen business was estimated.The experimental results obtained gave the gas concentration of 57.5% in a Steam/Carbon ratio of 1.40 at 900 °C.Assuming the plant scale of 10 t/d, the production amount of hydrogen gas would be 21.3 kg/h. Based on the law concerning waste processing in Japan, a sizeable amount of waste biomass could be expected. Therefore, if the processing fee which is paid to the group (contractor) ranges between 5.0 and 10.0 $/t, and if the whole investment cost is 6 million dollars and the depreciation period is 15 years, the bio-hydrogen production cost using the experimental data would be 5.75–7.86 $/kg-H₂ without receiving related subsidies. In a one-third grant proportion, the cost would become 4.60–6.72 $/kg-H₂.     

Crystallographic evaluation of ZnSe crystals by x-ray diffraction

Crystallographic quality and the lattice constant of ZnSe crystals grown from Te/ Se solutions by the temperature gradient solution growth method were evaluated by using a high resolution x-ray diffractometer. The full width at half maximum of the x-ray rocking curve was 5.7 sec, a value almost equivalent to that of GaAs. The distribution of crystallographic properties along the growth direction was nearly the same excepting just on the heat-sink. The accurate lattice constant of the ZnSe crystal measured by this system was 5.6700 ± 0.000025 A.     

Simulation of high speed deformation of copper single crystals

Plastic deformation of copper single crystals was simulated by molecular dynamics using an embedded atom potential. The time step of molecular dynamics is on the order of 1 fs which corresponds to ultra high speed deformation. This paper reports the results of tension, bending, and compression tests. On notched tension surfaces, Heidenreich-Shockley partial dislocations formed near the tip of the notch as expected. In the absence of notch, creation of dislocations was quite difficult under tension. On compression surfaces, partial dislocations were generated near the wrinkle of the possibly redundant slip plane.     

Effectiveness of an energy-consumption information system for residential buildings

The authors have proposed a method of reducing the energy consumption in residential buildings by providing household members with information on energy consumptions in their own houses. An on-line interactive “energy-consumption information system” that displays power consumptions of, at most, 18 different appliances, power and city-gas consumption of the whole house and room temperature, for the purpose of motivating energy-saving activities has been constructed and the effectiveness of the system investigated by installing it in 10 residential buildings. The experiment showed that energy-saving consciousness was raised and energy consumption was in fact reduced by the energy-saving activities of the household members. In this paper, the system is described in detail and the effectiveness of reducing energy-consumption of the whole house and for space heating will be discussed. Also the energy-saving activities in a certain household are shown by using load duration curves.     

Brainstem lesions and gustatory function: III. The role of the nucleus of the solitary tract and the parabrachial nucleus in retention of a conditioned taste aversion in rats.

Bilateral electrolytic lesions of the nucleus of the solitary tract (NST) or ibotenic acid lesions of the pontine parabrachial nuclei (PBN) failed to disrupt retention of a preoperatively acquired conditioned taste aversion (CTA) to 0.3 M alanine. For both sham- and NST-lesioned rats, the CTA persisted following 3 nonreinforced conditioned stimulus (CS) presentations. For PBN-lesioned rats, retention was more labile. The preoperatively acquired CTA was extinguished by the 3rd nonreinforced CS exposure. When assessed postoperatively using a novel CS, NST-lesioned rats acquired a new CTA, although they were rendered anosmic with zinc sulfate (P. S. Grigson et al, see record 199707487-016). Rats with PBN lesions, however, failed to acquire a 2nd CTA postoperatively. Thus, the PBN is essential for the acquisition of a CTA, but neither of the brainstem gustatory nuclei need be intact for the retention of a preoperatively acquired CTA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of linear systems with time delay and unknown order

This paper proposes a system identification method for linear systems with time delay and unknown order. We hypothesize a number of candidate models, which have different order, because system order is unknown. In each model, we estimate the model parameters based on the maximum likelihood method by using nonlinear optimization technique. Then both local optimization technique and global search method are used because the estimated parameters may fall into a local minimum. After all candidate model's parameters are estimated, one model is selected among these models to estimate the system order by using a posteriori probability based on Bayes's theorem. Finally, the validity of the proposed method is demonstrated by numerical examples. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(3): 61–68, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10166     

Specific contact resistivity of indium contacts to n-type CdTe

Indium alloyed to n-type CdTe of about 10¹⁶ cm^-3 electron concentration provides a contact resistivity of about 7 x 10^-3 ohm cm². This is achieved by alloying for 10 minutes at 150-450‡C in a sealed ampoule with an overpressure of cadmium. If the alloying is done in an open tube H₂ flow without a Cd vapor overpressure, alloying temperatures above 250‡C cause the contact resistance to rise as cadmium vacancies increase the compensation in the CdTe. Further improvement of the contact resistivity to 1 x 10^-3 ohm cm is obtained by a 900‡C diffusion of In into the n-CdTe (electron concentration 10¹⁶ cm^-3 before the diffusion).     

Steep Impulse Voltage Characteristics of Suspension Insulators

Transmission and distribution lines are sometimes struck by lightning and there is some risk of electrical puncture of suspension insulators due to high and steep lightning surge voltage. When the insulators suffer from steep lightning surge voltages, the solid insulating body of the insulators sometimes is punctured before external flashover in the air occurs. These characteristics were investigated on the insulators in the laboratory by using different steep impulse voltages. From the investigation results, both V-t characteristics of external flashover and internal puncture were obtained on the insulators. It was found that the puncture of the insulators is a matter of probability, depending on the dimensions of the insulators, steep impulse voltages and number of impulse voltage applications. Especially, the effect of number of voltage applications on puncture probability was clarified and partial damage by a small number of voltage applications was verified before complete puncture occurred. Based on the study results, an empirical equation relating to probability of puncture (P), impulse voltage (V) and number of voltage applications (N) was established.     

Heat capacities of NpN and AmN

The heat capacities of NpN and AmN were determined with the drop calorimetry method. The NpN and AmN samples were prepared by the carbothermic reduction of the respective dioxides. The heat capacity of NpN obtained was in good agreement with the reported values in the temperature range from 334 to 1067 K, which was close to those of UN and PuN. The heat capacity of AmN was obtained experimentally for the first time, which was slightly smaller than those of UN, NpN and PuN in the temperature range from 354 to 1071 K.     

Nonstoichiometric behavior and phase stability of rare earth manganites at 1200°C: (1). LaMnO3

The perovskite phase LaMnO_3±λ was revealed to have nonstoichiometry ranging from 2.947 to 3.079 under the oxygen partial pressure below logPO₂(atm)=0 at 1200°C. The presence of the reductive perovskite phase LaMnO_3?λ with a more distorted structure than the monoclinic one was ascertained. The free energy change of oxidative reaction in MnO+1/2La₂O₃+1/4O₂=LaMnO₃ was determined to be ΔG°=19500±200cal at 1200°C. D.C. electrical conductivities of LaMnO_3±λ perovskites at room temperature became higher with increasing oxygen content. Magnetic measurements were also made.