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1.
We propose a super Lax type equation based on a certain class of Lie superalgebra as a supersymmetric extension of generalized (modified) KdV hierarchy. We are able to construct an infinite set of conservation laws and the consistent time evolution generators for generalized modified super KdV equations. Thefirst few of the conserved currents, the (modified) super KdV equation and the super Miura transformation are worked out explicitly in the case of twisted affine Lie superalgebraOSp(2/2)(2).Partially supported by the Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture (#01540246 and #01790203).RIFP will be known as Yukawa Institute for Theoretical Physics from June 8, 1990  相似文献   
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3.
A new, wide-band, high-speed and high-sensitivity THz detector has been developed. The prototype detector consists of a parabolic cylindrical mirror, a long wire antenna and a Schottky barrier diode. Direct detection measurements have shown a stable sensitivity of 150 ± 50 V/W for 1–2 THz without any adjustments. The long wire antenna was fixed at the focus of parabolic cylindrical mirror then it has been realized less operation steps, easy coupling to the external THz signals and a dramatic enhancement in the practicality of this system. The optically polished mirror and frosted surface one showed comparable sensitivities, thus easy polishing and less cost mirror fabrication can be applied for this system. The radiation pattern showed a maximum radiation angle of approximately 23° with its dominant main lobe, which was attributed to the wire antenna character and confirmed good agreements with classical antenna theory.  相似文献   
4.
We have investigated the effect of the surface state and surface treatment of the pores of an inorganic substrate on the plasma‐grafting behavior of pore‐filling‐type organic/inorganic composite membranes. Shirasu porous glass (SPG) was used as the inorganic substrate, and methyl acrylate was used as the grafting monomer. The grafting rate increased as the density of silanol on the SPG substrate increased. This result suggests that radicals are generated mainly at the silanol groups on the pore surface by plasma irradiation. The SPG substrates were treated with silane coupling agents used to control the mass of organic material bonded to the pore surface. The thickness of the grafted layer became thinner as the mass of organic material bonded to the pore surface of SPG increased. This decrease in the thickness of the grafted layer could be explained by the decrease in the penetration depth of vacuum ultraviolet rays contained in plasma having a wavelength of less than 160 nm that generated radicals in the pores of the substrate. The thickness of the grafted layer inside the SPG substrates could be controlled through the control of the mass of organic material bonded to the pore surface of the SPG substrate. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 846–856, 2006  相似文献   
5.
Hisanaka Ito  Takeo Taguchi 《Tetrahedron》2005,61(46):10868-10879
The reactions of γ,γ-dialkoxyallylic zirconium species with carbonyl compounds in the presence of Lewis acid are reported. The reactivity of γ,γ-dialkoxyallylic zirconium species and reaction pathway were strongly dependent on the structure and electrostatic nature of the carbonyl compounds.  相似文献   
6.
Hoshi S  Yamada M  Inoue S  Matsubara M 《Talanta》1989,36(5):606-608
Preconcentration by collection of metal complexes on chitin has been applied to the spectrophotometric determination of iron in water. The iron is collected as its 1,10-phenanthroline (phen) complex on a column of chitin in the presence of tetraphenylborate as counter-ion. The iron(II)-phen complex retained on the chitin is eluted with an acetone-1M acetic acid mixture (8:2 v/v), and the absorbance of the eluate is measured at 512 nm. Beer's law is obeyed over the concentration range 1.1-11.2 mug of iron in 10 ml of eluate. In the presence of EDTA as masking agent, Ca, Mg, Al, Mn, Zn, Cd and Pb do not interfere in concentrations up to 100 times that of iron(II) and Co, Ni and Cu do not interfere in concentrations up to 20 times that of iron(II). Common inorganic anions do not interfere in concentrations up to 10,000 times that of iron(II). The proposed method has been applied to determination of iron in tap water.  相似文献   
7.
Various kinds of 5'-O-unsaturated acyl 5-fluorouridines were synthesized to obtain 5-fluorouridine derivatives with low toxicity and high antitumor activity. Antitumor activity of the compounds against L-1210 leukemia in mice was examined, and the 5'-O-4-pentenoyl derivative showed the highest antitumor activity.  相似文献   
8.
To detect a lectin from soybean, an electrochemical procedure was developed by the use of a labeling of galactosamine. Because the lectin has binding sites to galactosamine, galactosamine labeled with daunomycin having electroactivity was prepared. When labeled galactosamine (LG) combines with lectin, the part of daunomycin is taken in the binding sites of the lectin and becomes electroinactive. Therefore, the concentration of the lectin can be estimated by measuring the peak current of the LG. On the other hand, a competitive reaction to the lectin of galactosamine and the LG makes a detection of galactosamine possible. This method has merit that does not require a separation procedure of the free LG from the bound one. An effect of length of spacer between daunomycin and galactosamine was also investigated. It was found that adsorption of reagent on the electrode increased due to introduction of the spacer. Furthermore, the electrode response of the LG was influenced by the type of the spacer.  相似文献   
9.
A single-chain amphiphile containing a rigid Schiff base segment, 3-cyano-N-benzylidene hexadecylamine (CNBHB) in the polar head group was synthesized and studied for its vesicle-forming properties. The dependence of the aggregation behavior of the vesicles as such and in the presence of manganese ions were studied as a function of temperature using differential scanning calorimetry and turbidity measurements. Transmission electron microscopy (TEM) was used to analyze the morphology of the vesicles, showed interesting features with fusion of regular structures, and were quite stable. In the presence of manganese ions, fusion of vesicles takes place. This could be due to the metal ions that are bound to the surface of the vesicles that cause a partial destruction of the hydration shell on the surface of the vesicles. The reduction in the hydration force could thus be responsible for the fusion.  相似文献   
10.
A new family of antitumor prodrugs (1-3) of 5-fluorouracil (5-FU) possessing photolabile 2-nitrobenzyl chromophores have been designed and synthesized to investigate the efficiency and mechanism of photoactivated 5-FU release upon UV-irradiation at lambda(ex)= 365 nm. The photoactivated prodrug 3 derived from conjugation of 2 with a tumor-homing cyclic peptide Cys-Asn-Gly-Arg-Cys (CNGRC) was so designed as to manifest a tumor-targeting function.  相似文献   
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