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151.
152.
The spectroscopic properties of metal-ion complexes of several imidazopyrazinone derivatives with Li+, Mg2+, Ca2+, Ba2+, Sc3+, and La3+ ions were studied. The spectral characteristics and the formation constants of the complexes changed continuously depending on the Lewis acidity of the metal ion, suggesting that the imidazopyrazinones can find application as indicators of Lewis acidity. In the case of bis-imidazopyrazinone derivatives, the complexation abilities were enhanced by chelate effects. 相似文献
153.
N. Hirano 《Journal of Mathematical Analysis and Applications》2005,311(2):545-566
In this paper, we consider the existence of infinitely many solutions of noncooperative elliptic systems perturbed from odd cases. 相似文献
154.
This paper discusses optical safety issues in distributed Raman amplification systems. Given the extremely high pump powers, network service operators have critical issues for safety. This paper focuses on both “eye-hazard” and “fire-hazards”. 相似文献
155.
Tsuneyuki Sato Naoki Higashida Tomohiro Hirano Makiko Seno 《Journal of polymer science. Part A, Polymer chemistry》2004,42(7):1609-1617
The copolymerization of divinylbenzene (DVB) and N‐isopropylacrylamide (NIPAm) with dimethyl 2,2′‐azobisisobutyrate of a concentration as high as 0.50 mol/L proceeded homogeneously without any gelation at 80 °C in N,N‐dimethylformamide, where the concentrations of DVB and NIPAm were 0.15 and 0.50 mol/L. The copolymer yield increased with time and leveled off over 50 min. Although DVB was consumed more rapidly than NIPAm, both comonomers were completely consumed in 50 min. The homogeneous polymerization system at 80 °C involved electron spin resonance‐observable propagating polymer radicals, the total concentration of which increased with time. The resulting copolymer was soluble in tetrahydrofuran, chloroform, acetone, ethyl acetate, acetonitrile, N,N‐dimethylformamide, dimethyl sulfoxide, and methanol, but insoluble in benzene, n‐hexane, and water. The copolymer showed an upper critical solution temperature (50 °C on cooling) in a methanol–water [11:3 (v/v)] mixture. Dimethyl 2,2′‐azobisisobutyrate fragments as high as 37–45 mol % were incorporated as terminal groups in the copolymers through initiation and primary radical termination. The contents of DVB and NIPAm were 10–30 mol % and 30–50 mol %, respectively. The intrinsic viscosity of the copolymer was very low (0.09 dL/g) at 30 °C in tetrahydrofuran despite high weight‐average molecular weight (1.2 × l06 by multi‐angle laser light scattering). These results indicate that the copolymer was of hyperbranched structure. By transmission electron microscopy observation, the individual copolymer molecules were visualized as nanoparticle of 6–20 nm. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1609–1617, 2004 相似文献
156.
Homogeneous, crack-free, thin films of crystalline LiNbO3 were synthesized above 250°C on Si(100) substrates by the dip-coating method using a double alkoxide solution. The coating solution, which was prepared by the controlled partial hydrolysis of the double alkoxide, gave stoichiometric LiNbO3 crystalline films at temperatures as low as 250°C. The concentration of the alkoxide solution influenced both of thickness and quality of films. Crystallinity of thin film top-coated directly on the substrate affected the crystallization state of films coated on the film remarkably. Films crystallized on -Al2O3(0001) showed preferred orientation along the c-axis, while the preferred orientation could not be observed on Si(100) substrates. 相似文献
157.
T Kume R Taguchi M Tomita S Tokuyama K Morizawa O Nakachi J Hirano H Ikezawa 《Chemical & pharmaceutical bulletin》1992,40(8):2133-2137
The properties of phosphatidylinositol-specific phospholipase C (PI-PLC) from Bacillus thuringiensis were studied in detail. The enzyme was extremely thermostable in 0.1% bovine serum albumin and retained 73% of its activity at 100 degrees C for 10 min, while it was labile in the absence of albumin. The enzymatic activity was inhibited by HgCl2 or p-chloromercuriphenylsulfonic acid and restored by dithiothreitol. The kinetic parameters (Km and Vmax) of PI-PLC were determined for the mixed micelle of yeast phosphatidylinositol (PI)/Triton X-100 or sodium deoxycholate. Four PIs having different acyl chains: dilauroylphosphatidylinositol (DLPI), dimyristoylphosphatidylinositol (DMPI), dipalmitoylphosphatidylinositol (DPPI) and dioleoylphosphatidylinositol (DOPI) were synthesized from yeast PI through the processes of deacylation and reacylation, identified by infrared (IR) and Fourier transform nuclear magnetic resonance (FT-NMR) spectra, and subjected to the action of PI-PLC. All the synthetic PIs were hydrolyzed by this enzyme, with DLPI and DMPI being the best substrates. PI-PLC did not catalyze the hydrolysis of the phosphatidylnucleosides 5'-phosphatidylcytidine, 5'-phosphatidyluridine, 5'-phosphatidylthymidine, 5'-phosphatidyladenosine and 5'-phosphatidyl-2'-deoxyadenosine. 相似文献
158.
159.
Broadband high level squeezing was clearly observed from 100 kHz to 80 MHz using crystals Ba2NaNb5O15 of 5 mm length, MgO:LiNbO3 of 19 mm length and KNbO3 of 5.8 mm length. Maximum noise reductions detected on a spectrum analyzer were –1.2 dB (–24%), –1.25 dB (–25%), and –1.8 dB (–34%) for the three crystals, respectively. The maximum squeezing is limited mostly by optical index damage of the parametric crystals. A detailed analysis of the beam parameters traced along the pump beam, squeezed vacuum, etc. is given. A detailed discussion on the evaluation of the initial squeezed level is given. A preliminary experiment with compressed laser pulses to avoid the optical damage is also described. 相似文献
160.
Nobuo Kitada Tsuyoshi Saitoh Yuma Ikeda Satoshi Iwano Rika Obata Haruki Niwa Takashi Hirano Atsushi Miyawaki Koji Suzuki Shigeru Nishiyama Shojiro A. Maki 《Tetrahedron letters》2018,59(12):1087-1090
The synthesis and bioluminescence of allyl-substituted luciferin derivatives as substrates for firefly luciferase are reported. The allylation of luciferins induced bathochromic shift (15–40?nm) of the bioluminescence emission. Upon combination with other chemical modifications for bioluminescence wavelength tuning, novel red emitting luciferin analogues were obtained with emission maxima at 685 and 690?nm. 相似文献