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191.
The 6-, 9-, 12-, 15-, 18-, 21-, 24-, and 27-membered unsaturated thiacrown ethers 1-8 were formed by reaction of cis-1,2-dichloroethylene with sodium sulfide in acetonitrile. Crystal structures of 4-8 were determined by X-ray crystallography, and it was found that all sulfur atoms of 5-8 direct to the inside of the ring (endodentate). All of the ORTEP drawings show that there are cavities in these molecules, and the cavity sizes in 4-8 were 1.76, 2.34, 3.48, 4.43, and 5.36 A, respectively. The UV spectra of 4-8 showed absorption maximums at the range of 255-276 nm in acetonitrile, and the absorption maximums of 4-8 were found to shift to longer wavelengths by changing the solvent from acetonitrile to cyclohexane. The cyclic voltammograms of 4-8 indicate that the larger unsaturated thiacrown ethers were oxidized more easily than the smaller systems, and unsaturated thiacrown ethers were oxidized more easily than corresponding saturated systems. The reaction of 4 with silver trifluoroacetate in acetone afforded the colorless complex Ag(I)(C2H2S)5(CF3COO) 9. The crystal structure of 9 was determined by X-ray analysis, and it was found that three of the five sulfur atoms bonded to the silver atom. 相似文献
192.
A poly(amine ester) dendrimer with naphthyl units (G1N6) has been synthesized as a fluorescent chemosensor for metal ions. We investigated the metal-ion recognition of G1N6 by adding each of Ag(+), Al(3+), Ba(2+), Ca(2+), Cd(2+), Co(2+), Cu(2+), Fe(3+), Mg(2+), Ni(2+), and Zn(2+) in acetonitrile solution. Large changes were observed in the fluorescence spectra of G1N6 upon the addition of Al(3+), Cu(2+), and Zn(2+). 相似文献
193.
194.
L. Faybusovich T. Mouktonglang T. Tsuchiya 《Computational Optimization and Applications》2008,41(2):205-223
Based on previous explicit computations of universal barrier functions, we describe numerical experiments for solving certain
classes of convex optimization problems. The comparison is given of the performance of the classical affine-scaling algorithm
with the similar algorithm built upon the universal barrier function. 相似文献
195.
Midori O. Ishitsuka Hidefumi Nikawa Takahiro Tsuchiya Michael T.H. Liu 《Tetrahedron letters》2007,48(5):859-861
By employing C60 as a chemical probe, the photolysis of benzylchlorodiazirine has been proposed to form carbene and the rearranged products via the excited state. 相似文献
196.
Daisuke Ishikawa Yuki Suzuki Chikako Kurokawa Masayuki Ohara Misato Tsuchiya Masamune Morita Miho Yanagisawa Masayuki Endo Ryuji Kawano Masahiro Takinoue 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15443-15447
Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial‐cell engineering. Although particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilic DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and to stabilise the oil–water interface. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil–water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for the programmable design of microcapsules to engineer artificial cells and molecular robots. 相似文献
197.
198.
Gakuse Hoshina Shigeru Ohba Naoko Tsuchiya Tetsuhiko Isobe Mamoru Senna 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e191-e192
The title mononuclear iron(II) complex, [Fe(C12H8N2)3](NCS)2·3H2O, has a slightly distorted octahedral coordination. One of the thiocyanate ions and one of the water molecules of crystallization show positional disorder. 相似文献
199.
Finite curved boundaries are unavoidable in the practical field of non-invasive tissue spectroscopy. This being the case, a technique derived from the microscopic Beer-Lambert law (MBL) can be applied regardless of what geometry is assumed. Here, experimental tests on a type of time integrated spectroscopy based on the MBL for a tissue-like phantom with curved boundaries are presented. The experiments employed a cylindrical liquid phantom 56 mm in diameter, which resembles a human forearm. Two independent measurements were made on the surface of the phantom at various absorption levels (the absorption coefficients of the phantom were from 2.45 × 10−3 to 4.12 × 10−2 mm−1 at 782 nm), one in the direction along the circumference and the other along the long axis of symmetry. In both cases, the absorber concentrations were successfully recovered within error values of a few percent using a single equation. 相似文献
200.
C. Funayama T. Furukawa T. Sato Y. Ichikawa Y. Ohtomo Y. Sakamoto S. Kojima T. Suzuki C. Hirao M. Chikamori E. Hikota M. Tsuchiya A. Yoshimi C. P. Bidinosti T. Ino H. Ueno Y. Matsuo T. Fukuyama K. Asahi 《Hyperfine Interactions》2015,232(1-3):59-66
We demonstrate spin-exchange optical pumping of 129Xe atoms with our newly made laser system. The new laser system was prepared to provide higher laser power required for the stable operation of spin maser oscillations in the 129Xe EDM experiment. We studied the optimum cell temperature and pumping laser power to improve the degree of 129Xe spin polarization. The best performance was achieved at the cell temperature of 100 °C with the presently available laser power of 1 W. The results show that a more intense laser is required for further improvement of the spin polarization at higher cell temperatures in our experiment. 相似文献