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1.
Satz 41 in Hasse's monograph [4] is modified because of the incorrectness of Satz 29. We investigate unit indices of imaginary abelian number fields of type (2,2) and (2,2, 2), some of which give counterexamples to Satz 41. We moreover give a relation between unit indices of certain imaginary fields of type (2,22) and those of their real cyclic subfields. 相似文献
2.
A fast electrooptic modulation in a polymer waveguide using a ferroelectric liquid crystal has been proposed. In this device, the surface stabilized ferroelectric liquid crystal and the soft mode ferroelectric liquid crystal are used as an active material on the passive polymer waveguide, and electrooptic switching is realized by controlling the total reflection at the polymer waveguide-liquid crystal interface. The response time is of the order of several microseconds. The analogue electrooptic modulation in the waveguide is realized using the field induced linear molecular tilt of the electroclinic effect in the soft mode ferroelectric liquid crystal. 相似文献
3.
Yue Liu Masahito Ohta Grozdena Todorova 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2007
We study here instability problems of standing waves for the nonlinear Klein–Gordon equations and solitary waves for the generalized Boussinesq equations. It is shown that those special wave solutions may be strongly unstable by blowup in finite time, depending on the range of the wave's frequency or the wave's speed of propagation and on the nonlinearity. 相似文献
4.
The effects of vitamin E (E) deficiency on the formation of aliphatic aldehydes in rat plasma and liver were studied. Three-week-old Wistar male rats were fed either an E supplemented diet (2-ambo-alpha-tocopheryl acetate 20 mg/kg diet, designated as E supplemented diet group) or an E deficient diet (E deficient diet group). After 8 weeks, n-hexanal and (E)-4-hydroxy-2-nonenal (4-HN) in the plasma of the E deficient diet group were found to be 2.0 and 2.5-fold greater than those of the E supplemented diet group, respectively. The contents of aldehydes such as n-pentanal, n-hexanal, 4-HN in the liver were also significantly higher in the E deficient diet group than in the E supplemented diet group. These results indicate that some aldehydes, arising possibly from lipid peroxides, are produced and detected in the plasma and liver of rats under the condition like E deficiency. In this study we further found that the activity of the liver aldehyde dehydrogenase (ALDH, EC 1.2.1.3) was significantly changed; 5 and 8 weeks after the start it was lower in the E deficient diet group when compared to that in the E supplemented diet group. The decrease of enzyme activity was related to the increase of aldehydes such as n-hexanal in the liver. the aldehyde increase in the plasma of the E deficient diet group was thought to raise the injury of cells, namely, a strong hemolysis on erythrocytes prepared from the blood of rats fed the E deficient diet. 相似文献
5.
K Yoshino K Goto T Kohno T Morita G Tsukamoto 《Chemical & pharmaceutical bulletin》1990,38(3):676-680
Various asymmetric or cyclic ester derivatives of the phosphonic acid moiety in the calcium antagonist fostedil (KB-944) were synthesized. The coronary vasodilator activity of these compounds was assessed by Langendorff's method. Among them, the ethyl isopropyl ester 12 showed the most potent activity, which was comparable to that of fostedil. 相似文献
6.
An orally applicable pulsatile drug delivery system in dry-coated tablet form was prepared using diltiazem hydrochloride as the model drug, and a polyvinyl chloride-hydrogenated castor oil-polyethyleneglycol mixture as the outer shell of the tablet. In vitro drug release from the prepared tablet exhibited a typical pulsatile pattern with a 7 h lag phase (non-drug release period). This dosage form was orally administered to three beagle dogs under non-fasting and fasting conditions, and the plasma concentration level of diltiazem was determined according to time after administration. The result of the in vivo study in non-fasting dogs suggested that the drug could be released in the gastrointestinal tract as in the in vitro test. However, under the fasting condition, a large difference in the plasma concentration profile was found, suggesting that the disintegration time of the tablet tended to be influenced by the feeding condition of subject. 相似文献
7.
Ionizing radiations, which have already been utilized for the sterilization of medical supplies as well as gas fumigation, should be the final candidate to decontaminate “hybrid” biomaterials containing bio-active materials including enzymes because irradiation induces neither heat nor substances affecting the quality of the materials and our health. In order to check the feasibility of 60Co-gamma rays on these materials, we selected commercial proteases including papain and bromelain hybridized with commercial activated chitosan beads and demonstrated that these enzyme-hybrids suspended in water showed the significant radiation durability of more than twice as much as free enzyme solution at 25-kGy irradiation. Enhanced thermal and storage stability of the enzyme hybrids were not affected by the same dose level of irradiation, either, indicating that commercial irradiation sterilization method is applicable to enzyme hybrids without modification. 相似文献
8.
Matsumoto T Kamada Y Sugimoto T Tada T Noguchi S Nakazumi H Shiro M Yoshino H Murata K 《Inorganic chemistry》2003,42(17):5192-5201
Two donor molecules newly synthesized, dimethylthio- and ethylenedithio-tetrathiafulvalenothioquinone-1,3-diselenolemethides (1 and 2), were used to prepare their charge-transfer (CT) salts with a magnetic FeBr(4)(-) counteranion. For 1, a low electrical conducting 1:1 salt (1.FeBr(4)) was obtained, in which molecules of 1 are tightly dimerized in a one-dimensional (1D) stacking column. On the other hand, 2 gave a 2:1 salt (2(2).FeBr(4)) as two different kinds of plate crystals (I and II). Both I and II possess similar stacking structures of molecules of 2 in each 1D column with a half-cut pipelike structure along the c axis. However, for I, the stacking columns are aligned in the same direction along the a and b axes, while for II they are in the same direction along the a axis, but in the reverse direction along the b axis, resulting in the difference in the relative arrangement of molecules of 2 and FeBr(4)(-) ions between the two crystals. The room-temperature electrical conductivities of the single crystals of I and II were 13.6 and 12.7 S cm(-)(1), respectively. The electrical conducting behavior in I was metallic above 170 K but changed to be semiconducting with a very small activation energy of 7.0 meV in the temperature range 4-170 K. In contrast, II showed the semiconducting behavior in the whole temperature range 77-285 K. The corresponding nonmagnetic GaBr(4)(-) salts with almost the same crystal structure as I and II showed definitively different electrical conducting properties in the metal to semiconductor transition temperature in I as well as in the magnitude of activation energy in the semiconducting region of I and II. The interaction between the d spins of FeBr(4)(-) ions was weak and antiferromagnetic in both I and II, but the magnitude of the spin interaction was unexpectedly larger compared with that in the FeBr(4)(-) salt of the corresponding sulfur derivative of 2 with closer contact between the neighboring FeBr(4)(-) ions. These electrical conducting and magnetic results suggest a significant interaction between the conducting pi electrons and the d spins of FeBr(4)(-) ions located near the columns or layers. 相似文献
9.
A potentiometric and spectrophotometric investigation on the formation of zinc(II) complexes with Semi-Xylenol Orange (SXO or H(4)L) is reported. In an aqueous solution (mu = 0.1), three 1:1 complex species, MH(2)L, MHL(-), ML(2-), and a 1:2 complex, ML(6-)(2), seem to exist. In a strongly alkaline medium (above pH 12.5) the complexes may dissociate to give zinc hydroxide and L(4-). The formation of a hydroxy complex is not observed. The absorption maxima are at 445 nm (MH(2)L), 466 nm (MHL(-)) and 561 nm (ML(2-)), the molar absorptivities being 2.34 x 10(4), 2.42 x 10(4) and 3.14 x 10(4) 1.mole(-1) .cm(-1) respectively. The formation constants are (at 25 +/- 0.1 degrees ) log K(M)(ML) = 11.84, log K(M)(MHL) = 7.13, log K(M)(MH(2)L) = 2.70, log K(M)(ML(2)) = 16.60. 相似文献
10.
Automated selective iodometric methods for the determination of chlorine and oxychlorine species have been developed for use in the drinking water industry. By utilising kinetic-based methods, linear ranges observed were: chlorine, 0.2–10 mg l?1; chlorine dioxide, 0.3–10 mg l?1; chlorite ion, 0.08–5 mg l?1; and chlorate ion, 0.08–5 mg l?1. 相似文献