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1.
Experimental studies were conducted using molecular sieve zeolites to remove pungent smell components from a coffee aroma-containing gas evolved from roasted and ground coffee packed in a percolation vessel. The components such as methyl mercaptan or acetaldehyde were selectively adsorbed from coffee volatiles, and a decrease of pungent odor was recognized on sensory evaluation. The adsorption selectivity was based on pore sizes of adsorbents and molecular sizes of adsorbates. Zeolite 5Å was preferable to 4Å for separation efficiency of methyl mercaptan and recovery yield of residual volatile compounds. 相似文献
2.
GRACE KING EDWARD GOO TAKASHI YAMAMOTO KIYOSHI OKAZAKI 《Journal of the American Ceramic Society》1988,71(6):454-460
Crystal structure and defects of ordered ((Pb1- x Ca x )TiO3 ceramics have been investigated by transmission electron microscopy. The structure is determined to be tetragonal, belonging to point group 4 mm . Pb and Ca are in an ordered fcc arrangement on the A sites. In addition to the chemical ordering, there is ordering due to atomic shuffling or what has been referred to as electrical ordering. Two distinct sets of planar defects are observed in the same region. One set of planar defects are identified as antiphase boundaries that are the results of chemical ordering and the other set are displacement boundaries that are the results of electrical ordering. 相似文献
3.
Effects of Grain Size and Porosity on Electrical and Optical Properties of PLZT Ceramics 总被引:2,自引:1,他引:1
A group of transparent ferroelectric hot-pressed (Pb0.92 La0.08 )-(Zr0.65 Ti0.35 )0.98 O3 specimens with controlled grain size and constant porosity and a group of similar specimens with controlled porosity and constant grain size were prepared. The electrical and optical constants and polarization-reversal properties of these ceramics were determined as functions of grain size and porosity. When poled PLZT ceramics were aged, the polarization-reversal characteristic was quite asymmetric, apparently because a space-charge field, E8p , was generated during aging. From a detailed study of the behavior of the E8p , including its (1) generation with increasing aging time, (2) relaxation with repeated polarization reversals, (3) relaxation by heat depolarization, and (4) grain-size and porosity dependence, it is concluded that the space-charge layer is present inside every domain. This layer also explains the grain-size dependencies of the remanent polarization, piezoelectric constants, and Curie point. 相似文献
4.
TAKAHIRO WATANABE HIROSHI AKIYAMA SOHEILA MALEKI HIROHITO YAMAKAWA KEN IIJIMA FUMINORI YAMAZAKI TAKASHI MATSUMOTO SATOSHI FUTO FUMIHIRO ARAKAWA MASATOSHI WATAI TAMIO MAITANI 《Journal of Food Biochemistry》2006,30(2):215-233
A qualitative method for detection of peanuts in foods using polymerase chain reaction was developed. A universal primer pair CP 03‐5′/CP 03‐3′ was designed to confirm the validity of the DNAs for PCR. The plant‐specific amplified fragments were detected from 13 kinds of plants using the universal primer pair. In addition, for the specific detection of peanuts with high sensitivity, the primer pair agg 04‐5′/agg 05‐3′ was designed to detect the gene encoding the peanut agglutinin precursor. The primer pair specifically generates a 95‐bp amplified fragment from peanut genomic DNA. Five hundred femto grams of peanut genomic DNA can be detected using the established method. The same qualitative results were obtained from both model processed and nonprocessed food samples containing 0.001, 0.01 and 0.1% of peanut. Moreover, it was shown that the trace amount of peanut in the commercial food products could be qualitatively detected using this method. The reproducibility and applicability of the proposed methods were verified in a six‐laboratory collaborative study. 相似文献
5.
The decomposition behavior and mechanism of calcium sulfate in O2/CO2 pulverized coal combustion were studied in an entrained flow reactor. A reaction rate expression correlating the influence of various factors was proposed for CaS04 decomposition and it is able to predict CaS04 decomposition satisfactorily. Under the conditions investigated, the decomposition of CaS04 was found to be a regime of chemically controlled shrinking core reaction. A CO2-rich atmosphere enhances CaSO4 decomposition in absence of oxygen. CaSO4 particles have catalytic effect on formation of CO from CO2. A high SO2 concentration inhibits CaSO4 decomposition. The kinetics of CaSO4decomposition has obvious dependence on experimental facilities and conditions, whereas the activation energy has much lower dependence. The kinetics derived in this work is more appropriate for investigating desulfurization in O2/CO2 pulverized coal combustion because an entrained flow reactor has a much closer condition to that in O2/CO2 pulverized coal combustion than a TGA. 相似文献
6.
Improved Modified Switching Transient Pulse Width Modulation (MT‐PWM) Method Applied to H‐Bridge Type Step‐Down Converter
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TAKAO MORI HIROHITO FUNATO SATOSHI OGASAWARA FUMIHIRO OKAZAKI YUKITSUGU HIROTA 《Electrical Engineering in Japan》2016,194(3):59-69
The authors have devised a new method to decrease high‐frequency harmonics in a specific frequency band by modifying the switching transient slope. In previous studies, there were several problems in applying modified transient pulse width modulation (MT‐PWM) to actual converters. In this paper, three problems are solved using an improved MT‐PWM method. First, the MT‐PWM signal was obtained using a trial‐and‐error approach that involved complex computation procedures in the previous studies. In this paper, a new calculation procedure for obtaining the MT‐PWM waveform using a simple calculation is proposed. Second, a new controller (drain‐source voltage controller) based on voltage feedback is proposed in order to realize a modified switching transient to increase the stability of the switching operation. Third, the dependency of MT‐PWM on source voltage variation is investigated in order to implement MT‐PWM in an actual step‐down converter. From this result, the concept of a new type of controller with the source voltage variation taken into consideration is proposed. Finally, the authors attempted to apply MT‐PWM to an H‐bridge converter to expand the application of MT‐PWM. An H‐bridge converter with MT‐PWM for a dc motor drive is successfully operated in an experiment. 相似文献
7.
TAKESHI MINAMI TAKASHI BOKU KATSUHIRO INADA MASANORI MORITA YUKO OKAZAKI 《Journal of food science》1989,54(3):763-763
The major odor components of finely grated, raw garlic in the air of the human mouth have been studied. Immediately after garlic ingestion, tests of the mouth air of six subjects revealed two major peaks that were positively identified as being allyl mercaptan and diallyl disulfide; these findings are based on an evaluation of the fragment patterns of a GC-MS analysis and from the actual retention times of these authentic compounds. The allyl mercaptan level was higher than the level of diallyl disulfide, although both compounds smell like garlic. Our results suggest that after garlic ingestion, allyl mercaptan is the major garlic-smelling compound in human mouth air, and diallyl disulfide is secondary. 相似文献
8.
ANANG MOHAMAD LEGOWO TAMOTSU IMADE YUKINORI YASUDA KATSUICHIRO OKAZAKI SHIGERU HAYAKAWA 《Journal of food science》1996,61(2):281-285
The gel strength of ovalbumin mixed with α-lactalbumin (α-La) was determined after heating at 80°C for 15 min at pH 7.0 Gel strength of the mixture of 4%α-La and 4% ovalbumin was two times that of 8% ovalbumin. Modified α-La at Cys6-Cys120 (3 SSα-La) had low enhancement effects on ovalbumin gelation. Competitive ELISA using monoclonal antibody to α-La showed decreased binding reactivities after heating α-La with ovalbumin at specific concentrations. The decrease of total SH groups in the gel mixed with 3SS α-La was much less than when mixed with α-La. A disulfide bond of Cys6-Cys120 in α-La contributed to interactions between ovalbumin and α-La in heat-induced gels. 相似文献
9.
Accurate data for dielectronic recombination of tungsten ions are essential in the modeling of tungsten impurity transport and radiative power loss in International Thermonuclear Experimental Reactor (ITER). Theoretical calculations have been made for dielectronic recombi- nation (DR) rate coefficients of Br-like tungsten ions using a flexible relativistic atomic code (FAC) from i eV to 50 keV. Level-by-level calculations are carried out for evaluating the contributions to DR through all the relevant Kr-like tungsten ions autoionizing inner-shell excited configuration complexes: (3s23p63d10)-14s24p5nlntl' (n = 4-5, n' = 4-100,l' = 0-8), (4s24pS)-lnln'l' (n = 4-6, n' = 4-100, l' = 0-12). Comparison of the rate coefficients for 3s, 3p, 3d, 4s and 4p subshell excitations shows that the 4p subshell excitation dominates over the whole temperature region, 4s subshell excitation at low temperature and 3p, 3d subshell excitations at high temperature can not be neglected. In order to facilitate simple applications, the total DR rate coefficient, △n = 0,1 and 2 core excitations DR rate coefficients are fitted to an empirical formula. 相似文献
10.
HajimeOKAZAKI MichiakiADACHI Jin-ichiIGARASHI 《石油学报(石油加工)》2001,17(1):77-80
High VI lubricating oil is produced in hydrocracker through hydrocracking (HDC) and hydroisomerization reactions. In order to effectively produce high VI component, such as iso-pafaffins and monocyclic naphtenes, it is important to load suitable HDC catalysts and operate them in the appropriate reaction conditions. Nippon Mitsubishi Oil Corporation (NMOC) and its affiliate company, Nippon Mitsubishi Petroleum Refining Company (NMPRC) reported their original HDC catalysts four years ago in this Japan-China joint seminar in Beijing. NMOC and NMPRC operate their hydrocracker both in fuel oil production mode and in lubricating oil production mode. In lubricating oil production mode, high VI lubricating oil called VHDC are produced. In this paper, at first, the advantages of high VI lubricating oil are described. And then it is announced that NMOC and NMPRC have developed a new generation of HDC catalyst with higher cracking activity, higher middle distillate selectivity and longer life than the other commercial HDC catalysts. In addition to those properties, the catalyst is able to yield high VI lubricating oil as well. 相似文献