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991.
992.
Cations affect the topology and enzymatic proficiency of most macromolecular catalysts but the role of cations in DNAzyme peroxidation reactions remains unresolved. Herein, we use statistical methods (ANOVA, t-test and Wilcoxon Mann–Whitney non-parametric test) to demonstrate that there are strong associations between cations, DNAzyme topology, peroxidation substrate and peroxidation rates of G-quadruplex peroxidises. Ammonium cation was found to be superior to all tested cations, including potassium. A t-test indicated that NH4+ was better than K+ with a p-value = 0.05. Interestingly, the nature of the peroxidation substrate employed affected the dependence of peroxidation rate on the cation present and of the three substrates tested, 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), tyramine and 3,3′,5,5′-tetramethylbenzidine (TMB), ABTS was the most sensitive to the nature of cation present. 相似文献
993.
994.
In this paper, an automatic local remeshing method is proposed for merging two or more hybrid meshes consisting of prisms, hexahedra, pyramids and tetrahedra to reduce users' efforts and turnaround time for mesh generation as an extension of the local remeshing method for small devices by Ito et al. (AIAA J. 2009; 47 (5):1270–1276. DOI: 10.2514/1.40875 ). Two types of relationships between two volume meshes are considered: (1) a volume mesh containing the other smaller volume mesh inside (parent–child relationship) and (2) a volume mesh connecting to the other volume mesh (sibling relationship). The primary advantage of the proposed method over the existing ones is that it can handle the geometries in the two hybrid meshes intersecting each other. Two examples are shown to demonstrate the local remeshing method. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
995.
Takamasa Iimori Yasushi Nii Toshio Izawa Susumu Kobayashi Masaji Ohno 《Tetrahedron letters》1979,20(27):2525-2528
A new methodology which leads to α,β-unsaturated α-amino acids has been developed through a carbon-carbon forming reaction using ethyl cyanoformate and active methylene compounds in the presence of zinc chloride and triethyl amine. 相似文献
996.
997.
Yasushi Nishihara Seisuke Izawa Yoshiaki Inoue Yuushou Nakayama Takeshi Shiono Kentaro Takagi 《Journal of polymer science. Part A, Polymer chemistry》2008,46(10):3314-3325
Doubly functionalized polar norbornenes 3a – 3g substituted by both a variety of ester and cyano groups were polymerized by ring‐opening metathesis polymerization (ROMP) with a Ru carbene complex 2 bearing 3‐bromopyridine as a ligand (third generation Grubbs' catalyst) in a living manner. The successive hydrogenation of the main‐chain double bond in the synthesized living ROMP polymers 4a – 4g with a hydridoruthenium complex was exploited. The comparison of thermal properties of a series of ring‐opening metathesis polymers 4a – 4g with those of their hydrogenated derivatives 5a – 5g revealed the decrease of glass transition temperatures (Tg) but little change of the 5% decomposition temperature (Td5). In all cases examined in this study, a decrease of Tg by hydrogenation was around 20–40 °C, regardless of the ester substitutents. In the presence of the additional PCy3, triethylamine, and methanol after complete consumption of monomer 3a under the living ROMP condition, the tandem ROMP‐hydrogenation of the resulting polymer 4a generated in situ was attained under a H2 (9.8 MPa) atmosphere at 80 °C to afford the hydrogenated polymer 5a , retaining the narrow polydispersity of 1.03. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3314–3325 2008 相似文献
998.
Yasushi Aoki Terunobu Nakajyo Akira Tsunemi Jinfeng Yang Yasuhiro Okada Masafumi Yorozu Masafumi Hirose Fumio Sakai Akira Endo 《Research on Chemical Intermediates》2001,27(7-8):689-697
A compact pulse radiolysis system using a photocathode RF gun was installed at Sumitomo Heavy Industries. Some performance tests were conducted concerning the electron beam and the laser pulse. The energy and the per-pulse charge of the electron beam were measured to be 1.75 MeV max. and 1 nC. The fluctuation of the charge was restricted within 2%. The pulse widths of the electron pulse and the analyzing laser pulse were 20 ps and 15 ps, respectively. The timing jitter between electron pulse and the laser pulse was ±5.7 ps. Based on these measurements, the all-over time resolution can deduced to be about 25 ps. 相似文献
999.
In iniferter‐based photocontrolled radical polymerization optimal irradiation wavelength was examined for precise molecular design of star vectors, which can function as high‐performance gene carriers. Monochromatic light in the range from 330 to 400 nm with the interval of about 10 nm was irradiated to tetrafunctional iniferter, 1,2,4,5‐tetrakis(N,N‐diethyldithiocarbamylmethyl)benzene, in the presence of N,N‐dimethyaminopropylacrylamide (DMAPAAm), as a model monomer, in toluene. In all wavelengths tetrabranched polymers were produced except for 400‐nm‐irradiation. The highest conversion reaching to about 35% was observed at the wavelength of 370 nm after only 40 min of irradiation. There was no further increase in conversion by combination with another two wavelengths. HPLC analysis and NMR spectra showed that the polymerization at the optimal wavelength of 370 nm was occurred in a living manner with the ability to control the chain length (from about 5000 to 40,000) having very narrow polydispersity (about 1.6) by changing of the irradiation time, the intensity, and the monomer concentration. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4505–4512, 2008 相似文献
1000.
Yasushi Kamimura Osamu Haba Takeshi Endo Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2005,43(6):1210-1215
A first‐generation dendrimer ( 2 ), containing phenol groups in the exterior for solubilization in aqueous alkaline solutions, was evaluated as a new negative‐working, alkaline‐developable photoresist material. A negative‐working photoresist based on 2 , 4,4′‐methylenebis[2,6‐bis(hydroxymethyl)phenol] as a crosslinker, and diphenyliodonium 9,10‐dimethoxyanthracene‐2‐sulfonate as a photoacid generator was demonstrated. This resist gave a clear negative pattern through postbaking at 90 °C after exposure to UV light, which was followed by development with a 2.38% aqueous tetramethyl ammonium hydroxide solution at room temperature. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1210–1215, 2005 相似文献