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151.
New podand-type fluoroionophores having two pyrene moieties: 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfide (3), 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfoxide (4), and 2,2′-bis(1-pyrenylacetyloxy)diphenyl sulfone (5), have been synthesized by connecting two 1-pyrenecarbonylmethyl groups with the two hydroxy groups of 2,2′-dihydroxydiphenyl sulfide, sulfoxide, and sulfone, respectively. Their complexation behavior toward alkali metal ions was examined by fluorescence spectroscopy. Among these fluoroionophores, compound 4, having a sulfinyl group, showed high selectivity toward Li?. 相似文献
152.
A thermal lens detection device was developed to realize an easy-to-use, portable and sensitive detector for nonfluorescent molecules. Two laser diodes (658 nm for excitation and 785 nm for probe) were made coaxial in an optical unit and were coupled to a single-mode optical fiber. On a microfluidic chip, a small holder for the optical fiber was fixed, and micro-lenses (numerical aperture of 0.2) were also integrated inside the holder. The micro-lenses were designed to realize an adequate chromatic aberration (50 μm), which was essential for sensitive thermal lens detection. Compared with conventional thermal lens detection systems which required very laborious and accurate optical alignment with the microchannel, the new device needed just attachment-detachment of the optical fiber, which was important for practical application. The lower limit of detection was 10 nM for nickel(II) phthalocyaninetetrasulfonic acid tetrasodium salt solutions (model sample), and the absorbance was 9 × 10(-6) AU. The absolute number of molecules detected was less than 200 zmol. The coefficient of variance for 5-time attachment-detachment of the optical probe was as small as 3.6%. The technical development allowed integration of the thermal lens detection devices inside a microsystem (e.g. enzyme-linked immuno-sorbent assay system), and practical microsystems were realized with sensitivities several-orders higher than absorptiometry. 相似文献
153.
We have developed a temperature cycler for polymerase chain reaction (PCR) in a microwell fabricated on a polymer/glass chip. The entire system consisted of three subsystems, which included (1) a thermal conditioner, (2) a proportional-integral-derivative (PID) control signal conditioner and (3) a data acquisition subsystem. The subsystems were regulated coordinately by a ladder logic program written for the programmable logic control (PLC) so that an actual sample temperature could be timed, changed and maintained according to the programmed temperature cycles. The present temperature control system showed high accuracy, stability and minimum overshoot with reduced heating and cooling transition rates. Applicability of the temperature controller to the miniaturized PCR system with reduced volumes of aqueous sample droplets isolated in an oil phase was confirmed by successful amplifications of a target DNA sequence in the microwell. 相似文献
154.
Haraguchi N Kiyono H Takemura Y Itsuno S 《Chemical communications (Cambridge, England)》2012,48(33):4011-4013
Main-chain polymers of chiral imidazolidinone were successfully synthesized by reaction of chiral imidazolidinone dimers with disulfonic acid. Chiral imidazolidinones were incorporated into the main-chain of the polymer by ionic bonding. These polymers could be used as polymeric chiral organocatalysts for asymmetric Diels-Alder reactions. 相似文献
155.
We achieved reversible changes in length and spectrum of Ag nanorods based on plasmon-induced photoelectrochemical reactions. The changes are applied to multi-wavelength and dual-polarization photochromism in visible-infrared regions. It allows display of invisible images viewable only by infrared cameras. Also possible is display of superimposed visible and invisible images. 相似文献
156.
Takuma Takemura Ichiro Hayakawa Emi Fukasawa Tetsuya Sengoku Hideo Kigoshi 《Tetrahedron》2012,68(32):6477-6484
The diastereoselective aldol-type reaction of a γ-pyrone via a sodium anion has been developed. This reaction is useful for synthesizing γ-pyrone-containing natural products. Also, we applied the Mukaiyama aldol-type reaction of silyl enol ether of γ-pyrone by using TiCl4. This Mukaiyama aldol-type reaction of γ-pyrone indicated higher anti-aldol selectivity than the aldol-type reaction of a γ-pyrone with NaHMDS. 相似文献
157.
Aliakbar Dehno Khalaji Hossein Mighani Hamid Reza Bijanzadeh Kazuma Gotoh Hiroyuki Ishida 《Journal of chemical crystallography》2011,41(10):1515-1519
Abstract
New Schiff-base compound (E)-2-(2,5-dimethoxybenzylideneamino)phenol (1) was synthesized and characterized by elemental analyses, FT-IR and 1H-NMR spectroscopy and single crystal X-ray diffraction. Molecular orbital calculation has been carried out for 1 by using HF method at 6-31G basis set. The title compound 1 crystallizes in monoclinic system, space group C2/c, with a = 19.4581(13) ?, b = 9.5805(5) Ǻ, c = 13.8431(7) Ǻ, β = 93.471(2)°, V = 2575.9(3) Ǻ3 and Z = 8. In the crystal structure two molecules are stabilized by a pair of intermolecular O1–H1···N1i hydrogen bonds. The dimeric units are further linked via C6–H6···O3ii hydrogen bond. 相似文献158.
Yoshiki Nakata Kazuma Momoo Noriaki Miyanaga Takuya Hiromoto Kunio Tsuchida 《Applied Physics A: Materials Science & Processing》2013,110(1):173-177
In this paper,we fabricate a lateral phase change memory device composed of a Ge2Sb2Te5 nanowire (GST NW) fully confined in a tungsten electrode nanogap. A SiNx spacer is used not only as etch mask for the fabrication of the GST NW, but also as sacrificial layer for the lift-off process, which makes it feasible to fully confine the GST NW in the metal electrode nanogap. Electrical characterization shows that the device has unprecedentedly low threshold current and SET voltage of only 16 μA and 80 mV, respectively. 相似文献
159.
160.
K Amaike K Muto J Yamaguchi K Itami 《Journal of the American Chemical Society》2012,134(33):13573-13576
A nickel-catalyzed decarbonylative C-H biaryl coupling of azoles and aryl esters is described. The newly developed catalytic system does not require the use of expensive metal catalysts or silver- or copper-based stoichiometric oxidants. We have successfully applied this new C-H arylation reaction to a convergent formal synthesis of muscoride A. 相似文献