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1.
Shuichi Yamamoto Teruaki Morihiro Koichi Ariyoshi Turkan Aktas 《Drying Technology》2005,23(6):1319-1330
As the surface properties of the drying materials are very important not only for the drying rate but also for the quality change during drying, the effects of surface concentration on the drying behavior of liquid foods (sugar solutions) were investigated by isothermal drying experiments and by numerical calculation experiments. The isothermal drying experiments with gelled sugar solution systems (sucrose and maltodextrin) were carried out at various relative humidity (RH) values (RH = 0 to 84%). Separate experiments were carried out for determination of the desorption isotherms.
The isothermal drying curves of sugar solutions at RH = 0 to 51% were very similar. Numerical simulations also showed that the drying curves of these sugars at the surface concentration = 0 and 0.1 are almost the same, although the concentration distributions are different.
When a small amount of gelatin was added to sugar solutions, the drying rate decreased remarkably as the gelatin might form a thin film (skin) near the surface, and consequently the retention of ethanol increased. 相似文献
The isothermal drying curves of sugar solutions at RH = 0 to 51% were very similar. Numerical simulations also showed that the drying curves of these sugars at the surface concentration = 0 and 0.1 are almost the same, although the concentration distributions are different.
When a small amount of gelatin was added to sugar solutions, the drying rate decreased remarkably as the gelatin might form a thin film (skin) near the surface, and consequently the retention of ethanol increased. 相似文献
2.
Titanium oxides were reduced to metallic titanium using the liquid calcium floating on the molten CaCl2. A part of Ca dissolved into CaCl2 and reacted with TiO2 settled below CaCl2. The by-product CaO also dissolved by about 20 mol pct into CaCl2, which was effective in reducing the oxygen concentration in the obtained Ti particles. The compositional region in the Ca-CaCl2-CaO system was examined for the less oxygen contamination in Ti and the better handling in leaching. A large amount of the
residual calcium oxidized the titanium powder in leaching. The metallic Ti powder less than 1000 mass ppm oxygen could be
obtained only for 3.6 ks using 5 to 7 mol pct Ca-CaCl2 at 1173 K. The powder was slightly sintered like sponge, and contained approximately 1500 ppm Ca. The anatase phae, the intermediate
product in the refining process of TiO2, could be also supplied as raw material as well as rutile. 相似文献
3.
A method to estimate the acquisition time for the clock and data recovery (CDR) IC using the linear phase-locked loop (PLL) technique is proposed. Estimations using the method follow the measured acquisition time for the PLL with any loop parameters, which makes it possible to design the CDR IC for various targets. 相似文献
4.
5.
Shuichi Osanai Yoshiro Abe 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):43-45
Optically active and racemic quaternary ammonium cationics containing a chiral alkyl group, such as N,N-dimethyl-N-(1-phenylethyl)alkylammonium bromides were prepared and showed excellent antimicrobial properties against Gram positive and negative bacteria, with some exceptions, and against fungi. The influence of optical isomerism on their antimicrobial properties showed that the antimicrobial properties between racemic and optically active cationics were obscure. The order of activity of substituted alkyl groups was tetradecyl > dodecyl ° hexadecyl. 相似文献
6.
Hiroyuki Miki Takanori Takeno Toshiyuki Takagi Alexei Bozhko Mikhail Shupegin Hideya Onodera Takao Komiyama Takashi Aoyama 《Diamond and Related Materials》2006,15(11-12):1898
Superconductivity in a tungsten-containing carbon-oxide film was reported. The film with 500 nm thickness was deposited onto polycrystalline silicon oxides using chemical vapor deposition and the co-sputtering of a tungsten metal target. The bonding state of the carbon atoms and the macroscopic and microscopic crystal structure of the film were investigated by Raman spectroscopy, X-ray diffraction and transmission electron microscopy measurements. From the experimental results, we determined that this film essentially had an amorphous structure. The temperature dependence on resistivity was measured in the temperature range of 2–300 K. Resistive superconducting transition was observed at 3.8 K. The dc magnetizations were measured in the temperature range of 1.8–6.5 K. The diamagnetism resulting from a superconductive state was observed below 3.75 K, which is consistent with a resistive superconducting transition. It is thought that the finite sized clusters of the different superconductive transition temperatures cooperatively produce a macroscopic superconducting phenomenon. 相似文献
7.
Yasushi Sobajima Kunihiro Mori Masahiro Tsukamoto Norimitsu Yoshida Masao Takahashi Hikaru Kobayashi Shuichi Nonomura 《Solar Energy Materials & Solar Cells》2005,85(2):240-187
Effects of cyanide (CN) treatment with hydrogenated amorphous silicon (a-Si:H) films have been investigated. The decrease of ΔV/V was observed in cyanide treated a-Si:H films and the successive thermal annealing at 200°C after CN treatment induced the further reduction of the ΔV/V. XPS spectra show the indirect evidence that the cyanide species is present within 10 nm from the hydrogenated amorphous silicon surface. The results of CN treatment with a-Si:H solar cells are demonstrated. 相似文献
8.
Taxonomy for protective ability of rust layer using its composition formed on weathering steel bridge 总被引:2,自引:0,他引:2
For a quantitative evaluation of the protectiveness of a rust layer formed on a weathering steel bridge, the relationship between the corrosion rate of the bridge and the composition of the rust layers formed on the girders was first investigated. These corrosion rates were clearly classified by the protective ability index (PAI) of α/γ∗ and (β + s)/γ∗, where α, γ∗, β and s are the mass ratio of crystalline α-FeOOH, the total of γ-FeOOH, β-FeOOH and the spinel-type iron oxide (mainly Fe3O4), β-FeOOH and spinel-type iron oxide, analyzed by XRD, respectively. The inequality of the former index α/γ∗ > 1 expressed the protectiveness criterion of the rust layer, while that of the latter index, (β + s)/γ∗< 0.5 or > 0.5, classified the corrosion rate of the non-protective rust layer. The PAI is useful for a quantitative evaluation of the protectiveness of a rust layer formed on a weathering steel bridge and is an important item for the corrosion assessment of the bridge. 相似文献
9.
Tsugio Sato Kenji Dosaka Toshiaki Yoshioka Akitsugu Okuwaki Kazuo Torii Yoshiro Onodera 《Journal of the American Ceramic Society》1992,75(3):552-556
Amorphous CeO2 –ZrO2 gels were prepared by coprecipitation in ammonia solutions. The onset of crystallization of the gels, from calcining in air, was 420°C, while 200° to 250°C in the presence of water and organic solvents such as methanol and ethanol. The sintering behaviors of CeO2 –ZrO2 powders were sensitive to the crystallizing conditions, since hard agglomerates formed when the precipitated gels were crystallized by normal calcination in air, whereas soft agglomerates formed when they were crystallized in water or organic solvents. CeO2 –ZrO2 powders crystallized in methanol and water at 250°C were sintered to full theoretical density at 1150° and 1400°C, respectively, whereas that crystallized by calcination in air at 450°C was sintered to only 95.2% of theoretical density, even at 1500°C. 相似文献
10.
Kojima Shuichi; Takagi Nobuyuki; Minagawa Tetsuya; Fushimi Noriko; Miura Kin-ichiro 《Protein engineering, design & selection : PEDS》1999,12(10):857-862
We have previously shown that replacing the P1-site residue(Ala) of chicken ovomucoid domain 3 (OMCHI3) with a Met or Lysresults in the acquisition of inhibitory activity toward chymotrypsinor trypsin, respectively. However, the inhibitory activitiesthus induced are not strong. In the present study, we introducedadditional amino acid replacements around the reactive siteto try to make the P1-site mutants more effective inhibitorsof chymotrypsin or trypsin. The amino acid replacement AspTyrat the P2' site of OMCHI3(P1Met) resulted in conversion to a35000-fold more effective inhibitor of chymotrypsin with aninhibitor constant (Ki) of 1.17x1011 M. The Ki valueof OMCHI3(P1Met, P2'Ala) indicated that the effect on the interactionwith chymotrypsin of removing a negative charge from the P2'site was greater than that of introducing an aromatic ring.Similarly, enhanced inhibition of trypsin was observed whenthe AspTyr replacement was introduced into the P2' site of OMCHI3(P1Lys).Two additional replacements, AspAla at the P4 site and ArgAlaat the P3' site, made the mutant a more effective inhibitorof trypsin with a Ki value of 1.44x109 M. By contrast,ArgAla replacement at the P3' site of OMCHI3(P1Met, P2'Tyr)resulted in a greatly reduced inhibition of chymotrypsin, andAspAla replacement at the P4 site produced only a small changewhen compared with a natural variant of OMCHI3. These resultsclearly indicate that not only the P1-site residue but alsothe characteristics, particularly the electrostatic properties,of the amino acid residues around the reactive site of the proteaseinhibitor determine the strength of its interactions with proteases.Furthermore, amino acids with different characteristics arerequired around the reactive site for strong inhibition of chymotrypsinand trypsin. 相似文献