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101.
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.  相似文献   
102.
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer capacitors, etc.  相似文献   
103.
The fundamental characteristics of the direct-coupled pulse energization in electrostatic precipitators (EP's) are investigated in a test rig comprised of a coal pulverizing facility, a furnace, a gas cooling system, and an EP. The EP consisted of a corona electrode with barbed wires and a collection electrode with 300-mm duct spacing. This simulates the type of EP normally used in a coal-fired power station. The pulse-energized collection field shows a very high collection performance of more than 99 percent collection efficiency and the performance enhancement compared to the conventional dc energization, causing very severe back corona, becomes as large as H = 2.50.H is the enhancement factor in terms of the Deutsch migration velocity in the case of the very high resistivity dust of rd = 2 x 1013 ?cm at the gas temperature of Tg = 150°C. Even at the lower level of the dust resistivity at Tg = 110°C, where no back corona occurs in the dc-energized collection field, the performance enhancement is as large as H = 1.21. The mechanism of such great performance enhancement is likely to be the result of the very uniform and very intense formation of corona plasmas on the wires as a result of the very fast rise in the pulse voltage applied and a special sawtooth waveform of the operating voltage between the corona and collection electrodes.  相似文献   
104.
Chiral tagging reagents, 4-(N,N-dimethylaminosulphonyl)-7-(2-chloroformylpyrrolidin-1 -yl)-2,1,3- benzoxadiazole (R(+)-DBD-Pro-COCl and S(-)-DBD-Pro-COCl), react with mirror image enantiomers of amines to produce corresponding diastereomers in the presence of pyridine as a catalyst. The maximal excitation and emission wavelengths of the resulting diastereomers were ca. 450 nm and 560 nm, respectively. The diastereomers derived from some aliphatic amines were resolved by a reversed-phase chromatography with water-acetonitrile or normal-phase chromatography with n-hexane-ethyl acetate as the eluent. The reactivities of both enantiomers of DBD-Pro-COCl to chiral amines were almost comparable, whereas a slight difference of fluorescence intensity was observed with S(-)-DBD-Pro-COCl. When (S-)-DBD-Pro-COCl was used as the derivatization reagent, amines corresponding to S-configuration were eluted faster than R-configuration. The opposite elution order was obtained with the use of R(+)-DBD-Pro-COCl, instead of S(-)-DBD-Pro-COCl. The Rs values obtained from 1-cyclohexylethylamine (CEA) having aliphatic ring structure was larger than those of amines (1-(1-naphthyl)ethylamine (NEA) and 1-phenylethylamine (PEA)) having aromatic ring structures.  相似文献   
105.
This paper deals with the improvements in response time and reliability of the aWO3/LiClO4-PC (propylene carbonate) electrochromic display. Response time was improved by adopting the highly porous a-WO3 film, the porous reflector and the high surface area non-polarizable counter-electrode. Results from the reliability tests indicated that the ECD had a sufficient lifetime for practical applications such as in watches, clocks and calculators. The mechanism of performance drift upon cycling the display is investigated using ESCA, AES and atomic absorption methods.  相似文献   
106.
We have investigated the degradation mechanism of Al0.48In0.52As/In0.53Ga0.47As/ InP high electron mobility transistors (HEMTs) using WSi ohmic electrodes. Cross-sectional transmission electron microscopy (TEM) observation and en-ergy dispersive x-ray (EDX) analysis reveal impurities diffusion of gate electrode (titanium: Ti) and fluorine (F) in the AlInAs layer after a high temperature (Ta = 170°C operating life test for 500 h. The decrease of drain current (Ids) during life test shows linear dependence on square root of aging time. It suggests that the degradation is controlled by a diffusion mechanism. Hence, the estimated degradation mechanism of this device is related with decrease of carrier concentration in the epitaxial layer by these diffused impurities. On the other hand, TEM and EDX show no degradation of WSi/InGaAs interface after aging. Therefore, the WSi electrode for this type of HEMT demonstrates excellent high stability under the accelerated operating life test.  相似文献   
107.
108.
A new and efficient scheme is presented for evaluating the kernel function K, which occurs in the linearized theory of oscillatory airloads on a planar lifting surface in subsonic flow. Among many previous efforts of this sort, the present paper was inspired by Ueda's method [10] for computing the integral function B(X, r, k) appearing in the kernel.Firstly we point out that important are not only B but also the remaining part A of the kernel, since singularities are latent in A as well as B. Moreover, it is quite desirable to express the singularities, which often must be treated analytically, by using the original variable x0 rather than the modified one X.The second important problem concerns with the finite continuous part K?F, which must be numerically evaluated efficiently. A new method for this purpose is presented.This paper is restricted to the case where the frequency is real, namely the oscillation is neutrally stable.  相似文献   
109.
Although several sex pheromones of the family Geometridae have been characterized, investigations on Japanese species are limited. In order to obtain more information, screening using known sex pheromones and their analogs was carried out. The (Z,Z,Z)-3,6,9-triunsaturated and (Z,Z)-6,9-diunsaturated hydrocarbons with straight C19-C21 chains were synthesized by the Grignard coupling reaction as a key step starting from linolenic and linoleic acids, respectively. Oxidation of the homoconjugated trienes withm-chloroperoxybenzoic acid yielded a 111 mixture of three monoepoxy derivatives that could be separated by silica gel chromatography. The chemical structure of each positional isomer was confirmed using two-dimensional NMR techniques and MS measurements, which enabled characteristic fragment ions from the isomers to be identified. Field tests using lures incorporating only one of the above six hydrocarbons or nine epoxides were carried out in a forest in Tokyo. Consequently, attraction of male moths of 14 geometrid species in addition to four species in another family, the Noctuidae, was observed. It was concluded that hydrocarbons with a homoconjugated polyene system and the monoepoxy derivatives are important components of sex pheromones produced by Japanese lepidopterous insects, particularly the geometrid moths.  相似文献   
110.
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