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51.
Intra-board interconnection between optical waveguide channels is suitable for assembling high-speed optoelectronic printed wiring boards (OE-PWB). Here, we propose a novel optical interconnection method combining techniques for both wavelength-based optical waveguide addressing and plug-in optical waveguide alignment with a micro-hole array (MHA). This array was fabricated by the mask transfer method. For waveguide addressing, we used a micro passive wavelength selector (MPWS) module, which is a type of Littrow mount monochromator consisting of an optical diffraction grating, a focusing lens, and the MHA. From the experimental results, we found that the wavelength addressing operation of the MPWS module was effective for intra-board optical interconnection.  相似文献   
52.
Supramolecular nanofibers (SNFs) composed of low‐molecular‐weight π‐conjugated molecules exhibit attractive optical and electrical properties and are expected to be the next optoelectronic materials. In this work, five crystalline SNFs have been constructed from three dehydrobenzoannulene (DBA) derivatives. The DBAs were designed to assemble in one dimension in a strategy based on anisotropic crystal growth. The crystallinity of the SNFs allowed the molecular arrangements in the SNFs to be determined. Therefore the mechanism of construction and correlations between the molecular arrangements and optical and electrical properties could be considered. The results clearly indicate that the properties of the SNFs are affected by the chemical structures and molecular arrangements. Moreover, one of the SNFs exhibits a high charge‐carrier mobility (Σμ=0.61 cm2 V?1 s?1) because of its crystallinity and appropriate molecular arrangement. This systematic experimental study based on a proposed strategy has provided information for improving the electrical properties of SNFs. This strategy will lead to highly functional SNFs.  相似文献   
53.
The deuterium-decoupled 100 MHz 1H-NMR spectra of 2,3-dideuteromethyloxirane and its polymer prepared with a lattice-disordered zinc dialkoxide were analyzed with consideration of the deuterium isotope effects on proton chemical shifts. The results of 1H- and l3C-NMR studies indicated that the initiator for methyloxirane polymerization catalyzed by the diethylzinc-alcohol system was a lattice-disordered zinc dialkoxide, from the aspect of stereoregularity of the polymers obtained.  相似文献   
54.
The reaction of manganese(II) acetate with a xanthene-bridged bis[3-(salicylideneamino)-1-propanol] ligand, H(4)L, afforded the tetramanganese(II,II,III,III) complex [Mn(4)(L)(2)(μ-OAc)(2)], which has an incomplete double-cubane structure. The corresponding reaction using manganese(II) chloride in the presence of a base gave the tetramanganese(III,III,III,III) complex [Mn(4)(L)(2)Cl(3)(μ(4)-Cl)(OH(2))], in which four Mn ions are bridged by a Cl(-) ion. A pair of L ligands has a propensity to incorporate four Mn ions, the arrangement and oxidation states of which are dependent on the coexistent anions.  相似文献   
55.
Yuji Ishimori 《Physics letters. A》2008,372(10):1562-1573
A new energy-conserving numerical integration method for Hamiltonian systems is presented. The method is constructed by a parallel connection of n multi-stage schemes of order 2 and its order of accuracy is 2n.  相似文献   
56.
Journal of Theoretical Probability - This paper concerns the density of the Hartman–Watson law. Yor (Z Wahrsch Verw Gebiete 53:71–95, 1980) obtained an integral formula that gives a...  相似文献   
57.
58.
Novel polybenzamide-ureas have been synthesized by the polymerization of N-mesyloxyphthalimide with diamines in N-methyl-2-pyrrolidone in the presence of acid acceptors. The polymerization probably proceeds through the formation of ring-opened adducts, followed by elimination and rearrangement yielding 2-isocyanatobenzamide derivatives, which were subsequently reacted to give polybenzamide-ureas. These polymers had inherent viscosities of 0.12–0.34 and were soluble in a wide range of solvents, including pyridine and m-cresol, as well as polar aprotic solvents. All of the polymers had low softing temperatures in the range of 140–260°C, and thermal analyses showed that marked decomposition of the polymers occurred at around 200–300°C, presumably forming quinazolinedione rings by intramolecular deamination.  相似文献   
59.
Cellulose - Some textiles and apparel cannot be laundered, such as astronauts’ clothes on the space station, smart textiles that contain optical fiber electronic devices. Thus, self-cleaning...  相似文献   
60.
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