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991.
Koyo Matsuda Isao Yanagisawa Yasuo Isomura Toshiyasu Mase Tadao Shibanuma 《合成通讯》2013,43(14):2393-2402
Thioamides were treated with iodomethane, and then o,o′-diaminobiphenyl or bipyridyl to afford 6-substituted-5H-dibenzo- or dipyrido [1,3]diazepines in good yields. 相似文献
992.
Moriyuki Sato Yuzo Kawahara Shigekazu Morito Isao Yamaguchi Yasuhisa Fujita 《European Polymer Journal》2012,48(7):1177-1185
New visible light-emitting and temperature-sensitive poly(VCL-co-SA)/ZnO gel nanocompsites (GNs) 4 loaded with surface-modified ZnO nanoparticles NPs 3 with polyethylene glycol (PEG) chains were successfully prepared by the cross-linking of N-vinylcaprolactam (VCL), sodium acrylate (SA) and tetraethylene glycol dimethacrylate (TEGDM) in the presence of NPs 3. The NPs 3 having nanostructured size were prepared from ZnO NPs 2 with 2-bromo-2-methylpropionyl linkages on the surface, and sodium alcoholate of polyethylene glycol monomethyl ether (PEGME). The NPs 3 and the GNs 4 were characterized by FTIR, UV–vis absorption and photoluminescent (PL) spectroscopies, X-ray analysis measurements, TEM and SEM observations and dynamic light scattering (DLS) measurements. The measurements indicated that the GNs 4 with wurtzite crystal structures based on the ZnO NPs show absorptions and yellow light-emitting properties arising from the NPs 3, except for the GNs 4 containing a high weight % of NPs 3. The size of the GNs 4 drastically decreased with increasing temperature in the range of 20–35 °C, probably because of the induction of steric hindrance and enhancement of hydrophilic PEG chain concentrations inside the GN networks 4. 相似文献
993.
We propose a method for high-speed and highly accurate detection of the image difference by using the Fourier spectrum magnitude difference. The difference can be extracted from subtraction between the Fourier spectrum magnitude images of a standard image and a target image, which are multiplied by their Fourier spectrum phase images. The size effect against the detection result of difference was also investigated. 相似文献
994.
995.
Recent noteworthy developments in the field of two-dimensional(2D) correlation spectroscopy are reviewed.2D correlation spectroscopy has become a very popular tool due to its versatility and relative ease of use.The technique utilizes a spectroscopic or other analytical probe from a number of selections for a broad range of sample systems by employing different types of external perturbations to induce systematic variations in intensities of spectra.Such spectral intensity variations are then converted into2 D spectra by a form of correlation analysis for subsequent interpretation.Many different types of 2D correlation approaches have been proposed.In particular,2D hetero-correlation and multiple perturbation correlation analyses,including orthogonal sample design scheme,are discussed in this review.Additional references to other important developments in the field of 2D correlation spectroscopy,such as projection correlation and codistribution analysis,were also provided. 相似文献
996.
Abstract (+)-Malyngolide and (?)-2-epimalyngolide were synthesized from (S)-(?)-2,3-epoxy-2-nonyl-propanol, prepared by asymmetric epoxidation of allylic alcohol. 相似文献
997.
This review article focuses on how nature sometimes solves the same problem in the biosynthesis of small molecules but using very different approaches. Four examples, involving isopentenyl diphosphate, menaquinone, lysine, and aromatic polyketides, are highlighted that represent different strategies in convergent metabolism. 相似文献
998.
A screen-printed dissolved oxygen sensor was fabricated using cerium oxide-supported silver catalyst and polydimethylsiloxane (PDMS) film. A PDMS film of 3 μm thickness showed good permeability for oxygen and impermeability for hydrogen peroxide. The calibration curve has shown a linear relationship with a correlation coefficient of 0.996 for the dissolved oxygen concentration. The sensitivity and detection limit of the present sensor were calculated at -158 μA mM(-1) and 8.4 μM, respectively. 相似文献
999.
Nakamura S Ogasawara S Matuda S Saito I Fujimoto K 《Molecules (Basel, Switzerland)》2011,17(1):163-178
We demonstrated that 5-vinyldeoxyuridine ((V)U) and 5-carboxyvinyldeoxyuridine ((CV)U) can be used to photoligate a longer oligonucleotide (ODN) from smaller ODNs on a template. By performing irradiation at 366 nm, these artificial nucleotides make photoligated ODNs with high efficiency without any side reactions. Moreover, by performing irradiation at 312 nm, these photoligated ODNs were reversed to the original ODN. (V)U needs to be irradiated 366 nm for 6 h, but (CV)U needs to be irradiated at 366 nm for 15 min. Finally, we made a self-assembled structure with an ODN containing (CV)U and observed the photoligated ODN by photoirradiation. 相似文献
1000.