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971.
972.
We studied the defense mechanisms against the negative effects of tannins in acorns by using the Japanese wood mouse (Apodemus speciosus) and acorns of a Japanese deciduous oak Quercus crispula, which contain 9.9% tannins on a dry weight basis. For the experiment, we allocated 26 wood mice into two groups: acclimated (N = 12) and nonacclimated (N = 14). Mice in the nonacclimated group were fed only acorns for 10 d after 4 wk of receiving a tannin-free diet. In contrast, mice in the acclimated group received ca. 3 g acorns daily in addition to the tannin-free diet for the first 4 wk, then they were fed only acorns for 10 d. Body weight, food intake, and digestibility were monitored. In addition, the amount of salivary proline-rich proteins (PRPs) and abundance of tannase-producing bacteria (TPB) in the feces of mice were measured. Of the 14 mice in the nonacclimated group, 8 died, whereas only 1 of the 12 in the acclimated group died. During the first 5 d of feeding acorns only, mice in the nonacclimated group lost, on average, 17.5% of their body mass, while those in the acclimated group lost only 2.5%. Food intake, dry matter digestibility, and nitrogen digestibility were higher in the acclimated group than in the nonacclimated group. The results indicate that wood mice can mitigate the negative effects of tannins by acclimation. Path analysis revealed that increased secretion of PRPs and abundance of Lactobacillus type of TPB might explain the acclimation to tannins.  相似文献   
973.
The standard Gibbs energies of formation of Ni3B, Ni2B, o-Ni4B3(Ni0.586B0.414), m-Ni4B3(Ni0.564B0.436), NiB, and Ni3B2O6 of the Ni-B-O system have been determined by measuring electromotive forces of galvanic cells using a Y2O3-stabilized ZrO2 solid oxide electrolyte. The results are as follows:
Temperature range: 1198 to 1298 K
Temperature range: 1182 to 1285 K
Temperature range: 1193 to 1273 K
Temperature range: 1193 to 1273 K
Temperature range: 1203 to 1253 K
Temperature range: 1182 to 1393 K where the standard pressure is 1 bar (100 kPa).  相似文献   
974.
975.
In quantum information theory, superadditivity in the capacity of a quantum channel occurs as a special property. We present a method of calculating the mutual information analytically for binary linear codes by using square‐root measurement as the decoding process. Many examples of codes showing the existence of superadditivity in capacity have been given in the past, but the scope of the method was not clarified. In the present paper, we show that the method can be applied to any binary linear codes. We also show that the quantum channel capacity is almost fully attained in a finite codeword length by using approximation to simplex code. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 48–57, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20646  相似文献   
976.
The kinetics of diethyl dithiophosphate adsorption on chalcopyrite and tennantite has been studied by UV-visible spectroscopy at pH values of 4, 6, and 9. The concentration of diethyl dithiophosphate in the solution has been monitored as a function of time and pH for both minerals. It was found that the adsorption tendency of diethyl dithiophosphate on both minerals decreased with the increasing pH treatments. This is due to the existence of metal hydroxide species onto the mineral surface in more alkaline condition inhibiting the adsorption of diethyl dithiophosphate species. In comparison to that of chalcopyrite, tennantite possessed slightly higher adsorption of diethyl dithiophosphate in acid condition, while vice versa correlation observed at other pH treatments at where the coverage of metal hydroxide species obtained higher than that of chalcopyrite showing that the rate oxidation of tennantite is higher. An adsorption mechanism has been proposed and tested against the experimental kinetic data. Both the kinetic data and flotation studies are consistent with the proposed mechanism.  相似文献   
977.
This paper presents a new interior point nonlinear programming algorithm for optimal power flow problems (OPF) based on the perturbed KKT conditions of the primal problem. Through the concept of the centering direction, the authors extend this algorithm to classical power flow (PF) and approximate OPF problems. For the latter, CPU time can be reduced substantially. To efficiently handle functional inequality constraints, a reduced correction equation is derived, the size of which depends on that of equality constraints. A novel data structure is proposed which has been realized by rearranging the correction equation. Compared with the conventional data structure of Newton OPF, the number of fill-ins of the proposed scheme is roughly halved and CPU time is reduced by about 15% for large scale systems. The proposed algorithm includes four kinds of objective functions and two different data structures. Extensive numerical simulations on test systems that range in size from 14 to 1047 buses, have shown that the proposed method is very promising for large scale application due to its robustness and fast execution time  相似文献   
978.
Freeze concentration is one of the methods to concentrate solution by making pure ice in the solution. In general, the ratio of condensation is focused on, and so the research on the concentration captured in ice is very limited. However, quality improvement of eliminating impurities from wastewater is a very important task. In this study, the difference of initial morphology of ice was focused on and the influence on the freeze concentration was studied. It was found that the concentration of solute captured in ice was in the following order, from bigger value, multi-crystal ice, a single crystal ice with growth direction in a-axis and a single crystal ice with growth direction in c-axis. It was clarified that the ratio of concentration between the solute captured in ice and the solute in the mother solution varied from 1/10 to 1/250, depending on the crystal orientation of the ice.  相似文献   
979.
The effects of edge city formation on the structure of an existing core city are investigated. Focus is put on the phenomenon of ``vacated business district' in the core city. It is hypothesized that some area of land in an existing business district becomes vacant due to edge city formation because of the transformation and/or adjustment costs of land. Equilibrium configuration in a metropolitan area is investigated, and various comparative static analysis is performed by numerical simulation method. Received: January 2004 / Accepted: July 2004 The previous version of this paper was presented at the ARSC meeting (at Osaka) and the European Congress of Regional Science (at Dublin). We are grateful to the participants of both conferences for their helpful comments. We also thank to anonymous referees and the editor of this Journal for their useful comments and suggestions.  相似文献   
980.
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