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61.
Zhe  Zhang  Ushio  Toshimitsu  Ai  Zhaoyang  Jing  Zhang 《Nonlinear dynamics》2020,99(2):1253-1267
Nonlinear Dynamics - This paper proposes a novel stability condition for delayed fractional-order composite systems. First, we extend the vector Lyapunov function to the fractional-order systems to...  相似文献   
62.
Spider dragline silk is a biopolymer with excellent mechanical properties. The development of recombinant spider silk protein (RSP)-based materials with these properties is desirable. Formic acid (FA) is a spinning solvent for regenerated Bombyx mori silk fiber with excellent mechanical properties. To use FA as a spinning solvent for RSP with the sequence of major ampullate spider silk protein from Araneus diadematus, we determined the conformation of RSP in FA using solution NMR to determine the role of FA as a spinning solvent. We assigned 1H, 13C, and 15N chemical shifts to 32-residue repetitive sequences, including polyAla and Gly-rich regions of RSP. Chemical shift evaluation revealed that RSP is in mainly random coil conformation with partially type II β-turn structure in the Gly-Pro-Gly-X motifs of the Gly-rich region in FA, which was confirmed by the 15N NOE data. In addition, formylation at the Ser OH groups occurred in FA. Furthermore, we evaluated the conformation of the as-cast film of RSP dissolved in FA using solid-state NMR and found that β-sheet structure was predominantly formed.  相似文献   
63.
In this article we consider linear operators satisfying a generalized commutation relation of a type of the Heisenberg-Lie algebra. It is proven that a generalized inequality of the Hardy’s uncertainty principle lemma follows. Its applications to time operators and abstract Dirac operators are also investigated.  相似文献   
64.
Renewable energy is regarded as a clean energy source but has some problems, one of which is intermittency. To reduce this, the time-delay of hydrogen production by photosynthetic bacteria can be effective. In this study, we qualitatively evaluated the time-delay of hydrogen production by photosynthetic bacteria under various irradiation conditions, and we also quantitatively evaluated it by fitting the experimental data and the hydrogen production model with a genetic algorithm. As a result of model fitting, we found that the relationship between the lengths of the optimized time-delay of hydrogen production by photosynthetic bacteria and the amount of light irradiation is linear. And we also found that the time-delay of hydrogen production by photosynthetic bacteria had an upper limit under low light intensity. We have suggested the existence of an energy store mechanism in photosynthetic bacteria.  相似文献   
65.
66.
The general formula for multiple-beam interference due to regular slit arrays illuminated with partially coherent quasi-monochromatic light is derived. The correlation functions chosen for partially coherent light assume Gaussian, sinc and besinc forms of correlation. The intensity distribution in the interference patterns is presented and discussed as a function of the spatial coherence condition. It is shown that spatial coherence of the illumination largely affects the features of multiple-beam interference patterns.  相似文献   
67.
a one-step conversion of butyne-1,4-diol (1) to 2,3-di(phenylsulfinyl)-1,3-butadiene (4) and the conversion of this bis-sulfoxide to the sulfoxide-sulfone 6 and the bis-sulfone 5 are reported.  相似文献   
68.
Gold nanoclusters covered with 4-aminothiophenol (4-ATP) self-assembled monolayers (SAMs) were electrochemically assembled on an Au or ITO electrode. The assembly mechanism is discussed on the basis of results of electrochemical, FT-IR, and XPS measurements. The intensity of plasmon absorption of the gold nanocluster assembly was shown to be dependent on applied potential as a result of electrochemical doping/undoping of a counteranion in the polyaniline film.  相似文献   
69.
Three precise measurements for elastic pd scattering at 135 MeV/A have been performed with the three different experimental setups. The cross sections are described well by the theoretical predictions based on modern nucleon-nucleon forces combined with three-nucleon forces. Relativistic Faddeev calculations show that relativistic effects are restricted to backward angles. This result supports the two measurements recently reported by RIKEN and contradicts the KVI data.  相似文献   
70.
Iron(III) complexes with the general formula of [Fe (R-Himap)2]X and [Fe(R-Himat)2]X (Himap = shiff-base prepared from the condensation of 4-formylimidazole and 2-aminophenol, Himat = shiff base prepared from the condensation of 4-formylimidazole and 2-aminobenzenethiol, and R = H, Me, Ph; X = ClO4, NO3, BPh4) have been synthesized. The complexes have an N4O2 donor set or an N4S2 donor set. These complexes have 5 and 5 member rings around an iron(III) atom per one chelate ring, that is, "5-5 member rings". The crystal structure, Mössbauer spectra, magnetic properties and absorption spectra of the complexes were examined. In addition, [Fe (Himsa)2]ClO4 having "5-6 member rings" of an N4O2 donor set and [Fe (Ph-Himap)(Ph-imap)] obtained by the deprotonation of [Fe (Ph-Himap)2]ClO4 have been also synthesized, and the Mössbauer spectra and magnetic properties of those complexes were examined. The X-ray structure of a single crystal of [Fe (Himap)2]BPh4 was determined: C44H36N6BO2Fe, triclinic, space group P(# 2), a = 12.452(2) Å, b = 12.748(2) Å, c = 11.996(2) Å, = 103.97(1)°, = 90.78(1)°, = 84.70(1)° and Z = 2. The moiety of an iron atom of [Fe(Himap)2]BPh4 was a pseudo octahedron with an FeN4O2 geometry. [Fe(R-Himap)2]X was in high-spin state (about 5.9 B.M. at 80 K in solid state), and [Fe(R-Himat)2]X was in low-spin state (about 2.0 B.M. at 293 K). The complex [Fe(Himsa)2]ClO4 with "5-6 member rings" and the deprotonated complex [Fe(Ph-Himap)(Ph-imap)] were in the high-spin state (6.0 B.M. at 80 K). It is concluded that the ligand field strength of an N4S2 donor set is stronger than that of an N4O2 donor set.  相似文献   
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