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131.
Si photonics has attracted much interest over the last decade as it allows integration of photonic and electronic devices on a small Si chip, providing high-capacity, energy-efficient, and cost-effective optical interconnects. Active optical cables based on Si photonics are now commercially available for rack-to-rack interconnects in supercomputers and data centers. Shorter reach optical interconnects, i.e., inter- and intra-chip optical interconnects, have been studied as the next challenge for higher speed computing. Science and technology of advanced materials is essential for rapid development in this field, and therefore it is very appropriate to publish this focus issue in STAM.
This focus issue introduces state-of-the-art material and device technologies in Si photonics. The topics cover not only technologies for the optical interconnects but also optical sensing as a novel application.
We are grateful to the authors who contributed to this focus issue, and hope that it will help researchers understand the frontiers of Si photonics, stimulating novel concepts in material and device technologies, as well as novel developments in and applications of Si photonics. 相似文献
132.
Arata Nagasaka Koji Sakiyama Yasuhiko Bando Masahito Yamamoto Shinichi Abe Osamu Amano 《International journal of molecular sciences》2022,23(9)
The mammalian secondary palate is formed through complex developmental processes: growth, elevation, and fusion. Although it is known that the palatal elevation pattern changes along the anterior–posterior axis, it is unclear what molecules are expressed and whether their locations change before and after elevation. We examined the expression regions of molecules associated with palatal shelf elevation (Pax9, Osr2, and Tgfβ3) and tissue deformation (F-actin, E-cadherin, and Ki67) using immunohistochemistry and RT–PCR in mouse embryos at E13.5 (before elevation) and E14.5 (after elevation). Pax9 was expressed at significantly higher levels in the lingual/nasal region in the anterior and middle parts, as well as in the buccal/oral region in the posterior part at E13.5. At E14.5, Pax9 was expressed at significantly higher levels in both the lingual/nasal and buccal/oral regions in the anterior and middle parts and the buccal/oral regions in the posterior part. Osr2 was expressed at significantly higher levels in the buccal/oral region in all parts at E13.5 and was more strongly expressed at E13.5 than at E14.5 in all regions. No spatiotemporal changes were found in the other molecules. These results suggested that Pax9 and Osr2 are critical molecules leading to differences in the elevation pattern in palatogenesis. 相似文献
133.
Na-A and -X zeolites were synthesized from waste solutions in conversion of coal fly ash (Fa) to zeolite. The amorphous SiO2 and Al2O3 of Fa were completely dissolved to form Po, Pt, and Pc type zeolites in NaOH solutions at 85°C. Only 24% of Si4+ eluted from Fa were converted to the zeolites and the remaining waste solutions contained high Si4+ concentrations. When molar ratio SiO2/Al2O3 of the waste solutions was modified at 1.0≤SiO2/Al2O3≤2.0 by addition of NaOH-NaAlO2 solutions and the solutions were agied at 85°C, a single phase of Na-A zeolite was formed. The Na-X zeolite was formed at SiO2/Al2O3≥2.5 and its crystallinity was increased with increasing the SiO2/Al2O3 ratio, whereas the crystallinity of Na-A zeolite was decreased. At SiO2/Al2O3=7.3, a single phase of Na-X zeolite was produced. 相似文献
134.
Kunimitsu Kataoka Yasuhiko Takahashi Hideaki Nagai Yasushi Idemoto 《Materials Research Bulletin》2009,44(1):168-21881
Colorless platelet crystals of monoclinic Li2TiO3 with a maximum size of 5.0 mm × 5.0 mm × 0.5 mm were successfully grown by a flux method at 1373 K using a LiBO2-Li2O system flux. The stoichiometric chemical composition of Li2TiO3 was determined by the SEM-EDX, ICP-AES and density measurement using the single crystal samples. The thermal conductivity of the Li2TiO3 single crystals was evaluated using hot-disk method. A single-crystal X-ray diffraction study confirmed the monoclinic Li2SnO3-type structure, space group C2/c and the lattice parameters of a = 5.0623(5) Å, b = 8.7876(9) Å, c = 9.7533(15) Å, β = 100.212(11)°, and V = 427.01(9) Å3. The crystal structure was refined to the conventional values of R = 2.4% and wR=3.3% for 2187 independent observed reflections. The cationic arrangement of (LiTi2) layers in Li2TiO3 was precisely revealed by the structure analysis. 相似文献
135.
Japan and Sweden have similar ambitions and both similarities and differences when it comes to provide long term care (LTC) for their old age citizens. The study compares cost increase for LTC in Japan and Sweden in the time period 2000–2010 by decomposing the changes in costs into changes in the size of the old age population (65 years and above) , the distribution on level of dependency /disability by age-group and gender, the volume of provided LTC services in relation to level of dependency/disability and the unit costs for provided services. The analysis of needs of LTC services is based upon nationally representative sample surveys population studies completed in each country: Nihon University Japanese Longitudial Study of Aging and the Swedish Survey of Living Conditions with 19. 602 and 9.433 observations respectively. Data on LTC services provision by level of dependency/ disability is taken from nine Japanese municipalities collected by assessments in the LTCI-system and from surveys in eight Swedish municipalities. It is shown by the analysis that the rapid cost increase in Japan in the period 2000–2010, 108 %, has mainly been driven by the increase in the old age population. However, another important factor in the period 2000–2005 has been increased provision of LTC services given level of dependency. In Sweden the cost increase depending on population increase has been countered by decreasing levels of disability by age-groupand gender. Services provision given needs of LTC has not increased very much. As a result the cost increase in the time period 2000–2010 has been much lower, +6 %. 相似文献
136.
137.
In the polymer industry, separation equipment is required to separate unreacted monomers and solvents from polymers. In order to design such equipments, solubilities of gases and vapors in molten polymers are needed as fundamental data. It is very helpful if the weight-fraction Henry's constant, which gives solubilities of a solute at concentrated regions of a polymer, can be estimated by a predictive method.
In the present study, a new expression for the free volume term has been derived and is coupled with the UNIFAC model. The present UNIFAC-FV model was applied to common polymer systems. The weight-fraction Henry's constants were calculated for several volatile hydrocarbons and the calculated results were compared with the experimental data determined by a gas chromatographic technique.
The present UNIFAC-FV model with a new free volume expression was found to be helpful in predicting the weight-fraction Henry's constants of hydrocarbon solutes in molten polystyrene, in polypropylene, and in low-density polyethylene. It is advantageous that our model is applicable both supercritical gases and subcritical vapors with no adjustable parameters. 相似文献
In the present study, a new expression for the free volume term has been derived and is coupled with the UNIFAC model. The present UNIFAC-FV model was applied to common polymer systems. The weight-fraction Henry's constants were calculated for several volatile hydrocarbons and the calculated results were compared with the experimental data determined by a gas chromatographic technique.
The present UNIFAC-FV model with a new free volume expression was found to be helpful in predicting the weight-fraction Henry's constants of hydrocarbon solutes in molten polystyrene, in polypropylene, and in low-density polyethylene. It is advantageous that our model is applicable both supercritical gases and subcritical vapors with no adjustable parameters. 相似文献
138.
139.
140.
The cycloaliphatic epoxy resins were studied by various two-dimensional nuclear magnetic resonance (2D n.m.r.) spectroscopies. The 13C n.m.r. spectra of the epoxy resins were assigned by using DEPT and 2D INADEQUATE techniques and the 1H n.m.r. spectra were assigned by using 2D 1H---1H and 1H---13C COSY techniques. Complete characterization of the samples synthesized by the oxidation of cyclohexene derivatives not only revealed the existence of the stereochemical isomers resulting from the structural difference of the oxide rings in the samples but also provided the composition ratio of the isomers. 相似文献