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1.
A WDM compatible Edge-to-Edge Self-Routed optical packet switched network that simplifies the optical processing is proposed. The system employs all-optical packet label generation and recognition using coded superstructured Fiber Bragg gratings. 相似文献
2.
Teh Pick Ching 《ZDM》1997,29(3):94-96
It is often said that many pupils have hidden talent in mathematics. This hidden ability is rarely seen in a normal classroom teaching and learning situation if the focus of the teacher is on drilling with routine exercises. To allow pupils to display their mathematical talent and to break from mental set and fixation in mathematics, they must be given opportunity to think by themselves with mininum cue or guidance. The pupils could be left entirely on their own to show their mathematical creativity even on mathematical topics which have not been exposed to them. With this approach, five non-routine questions were administered one at a time to a standard 5 class. One out of the 25 pupils in the class consistently exhibited mathematical creativity and talent is answering the questions. Her responses were shown and discussed in this paper. 相似文献
3.
Wen Wei Lai Teh Chou Chang 《Journal of polymer science. Part A, Polymer chemistry》1995,33(7):1075-1083
A series of crosslinkable thermotropic liquid crystalline poly(ether-ester)s and copoly(ether-ester)s was prepared. All of the polymers were crosslinked by thermal treatment or photo-irradiation upon heating. The thermal stability and thermal crosslinking reaction of these polymers were investigated. These polymers also could be crosslinked by copolymerization with vinyl monomers, such as styrene or methyl methacrylate. The crosslinked polymers exhibited thermotropic liquid crystalline behavior after softening by heating. The phase behavior of linear polymers and crosslinked polymers was studied by differential scanning calorimetry (DSC) and an optical polarizing microscope equipped with a heating stage. © 1995 John Wiley & Sons, Inc. 相似文献
4.
Shandong Yuan Sharifah Bee Derouane-Abd Hamid Yongxue Li Pinliang Ying Qin Xin Eric G Derouane Can Li 《Journal of molecular catalysis. A, Chemical》2002,180(1-2):245-258
The conversion of n-C4H10 was undertaken on MoO3/HZSM-5 catalyst at 773–973 K and the phases of molybdenum species were detected by XRD. The XRD results show that bulk MoO3 on HZSM-5 can be readily reduced by n-C4H10 to MoO2 at 773 K and MoO2 can be gradually carburized to molybdenum carbide above 813 K. The molybdenum carbide formed from the carburization of MoO2 with n-C4H10 below 893 K is -MoC1−x with fcc-structure, while hcp-molybdenum carbide formed above 933 K. During the evolution of MoO3 to MoO2 (>773 K) or the carburization of MoO2 to molybdenum carbide (>813 K), deep oxidation, cracking and coke deposition are serious, in particular at higher reaction temperatures, these lead to the poor selectivity to aromatics. Aromatization of n-C4H10 can proceed catalytically on both Mo2C/HZSM-5 and MoO2/HZSM-5, the distribution of the products for the two catalysts is similar below 813 K, but the activity for Mo2C/HZSM-5 is much higher than that for MoO2/HZSM-5. 相似文献
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Evidence is presented which indicates that singlet → triplet intersystem crossing from the charge-transfer singlet state of electron donor-acceptor complexes is efficient only when a locally excited triplet state of a component molecule (donor or acceptor) lies below the charge-transfer singlet state. 相似文献
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9.
Linlin Li Dr. Shengjie Peng Yanling Cheah Peifen Teh Jin Wang Grace Wee Yahwen Ko Dr. Chuiling Wong Prof. Madhavi Srinivasan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(19):5892-5898
Novel, porous NiCo2O4 nanotubes (NCO‐NTs) are prepared by a single‐spinneret electrospinning technique followed by calcination in air. The obtained NCO‐NTs display a one‐dimensional architecture with a porous structure and hollow interiors. The effect of precursor concentration on the morphologies of the products is investigated. Due to their unique structure, the prepared NCO‐NT electrode exhibits a high specific capacitance (1647 F g?1 at 1 A g?1), excellent rate capability (77.3 % capacity retention at 25 A g?1), and outstanding cycling stability (6.4 % loss after 3000 cycles), which indicates it has great potential for high‐performance electrochemical capacitors. The desirable enhanced capacitive performance of NCO‐NTs can be attributed to the relatively large specific surface area of these porous and hollow one‐dimensional nanostructures. 相似文献
10.
Samira Bagheri Fereshteh Chekin Sharifah Bee Abd Hamid 《Russian Journal of Electrochemistry》2014,50(10):947-952
Anatase titanium dioxide nanoparticles (TiO2-NPs) were synthesized with and without gelatin via the sol-gel method. The TiO2-NPs were characterized by a number of techniques, such as thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR) and ultraviolet visible spectroscopy (UV-Vis). The particle sizes of the TiO2-NPs prepared with and without gelatin were ~13 and ~17 nm, respectively. The main advantage of using gelatin as a stabilizing agent is that it provides long-term stability for nanoparticles by preventing particles agglomeration. The results indicated that gelatin was a reliable green stabilizer, which can be used as a polymerization agent in the sol-gel method for synthesis of tiny size TiO2-NPs. Moreover, the composite film was prepared by synthesized TiO2-NPs nanoparticles and multi wall carbon nanotube (MWNT) on glassy carbon electrode (TiO2-MWNT/GCE). The TiO2-MWNT/GCE responded linearly to L-tryptophan (L-Trp) in the concentration of 1.0 × 10?6 to 1.5 × 10?4 M with detection limit of 5.2 × 10?7 M at 3 using amperometry. The studied sensor exhibited good reproducibility and long-term stability. 相似文献