Centralized load control system demonstration test (interim report)

The maximum power peak has sharpened in recent years owing to the widespread use of air conditioners and other such equipment. Additionally, the gap between power demand during the day and night, as well as that among the seasons, is widening, while the annual load factor is on the decline. These factors prevent the effective use of generating facilities and are driving costs up. Countermeasures in the form of promotion of load leveling from the demand side have become a national priority. It was in these circumstances that the New Energy and Industrial Technology Development Organization (NEDO) officially requested that Kyushu Electric Power Co., Inc. (KEPCO) develop a load leveling technology for the future. For eight years starting in 1986, KEPCO conducted a demonstration test in which it directly controlled customer water heaters and air conditioners in a district of the city of Kagoshima. In addition, the company started a test in 1994 to demonstrate load leveling effects through indirect load control in a district of the city of Fukuoka. This load control involved providing customers on the demand side with their own load curves, electricity charge data, and other information so that they would themselves experiment with electricity use. This paper will outline the Centralized Load Control System demonstration test and discuss the system configuration and the 1996 test results of indirect load control that generated effects such as a peak reduction of 0.1 kW per household. © 1999 Scripta Technica, Electr Eng Jpn, 128(2): 7–17, 1999     

Characterization of Flemion® membranes for PEFC

Perfluorinated ion exchange membranes were studied to clarify the characteristics of membranes required for polymer electrolyte fuel cells (PEFC). The influence of membrane thickness on gas permeability and the influence of incorporation of cations on water content and ac specific resistance of Flemion® and Nafion®117 were estimated. Gas permeation rates of the membranes decreased in inverse proportion to the increase of the membrane thickness and gas permeability coefficients were nearly constant and independent of the thickness. Hydrogen permeation rates of Flemion®S at 70°C were converted to 2.1 mA/cm² as current density. Water content changed by only 5% in the region of the ion exchange ratio from 0% to 100% and was independent on the kinds of incorporated cations in the region of the ion exchange ratio under 40% except for K⁺. Ac specific resistance increased markedly when the ion exchange ratio exceeded 50%. In the case that the ion exchange ratio was under 30%, ac specific resistance increased with decrease of the numbers of protons having no relation with the kinds of cations. Area resistance of Flemion® was smaller because it has higher ion exchange capacity and thinner thickness than Nafion®117.     

Crystallinity Analysis of Glass-Ceramics by the Rietveld Method

The crystallinity of multicomponent glass-ceramic mixtures has been analyzed via the Rietveld method, using powder X-ray diffractometry data. The Rietveld technique uses an internal standard but requires no calibration data to determine the total amorphous phase content of a mixture. This method of analyzing the crystallinity of synthetic mixtures gives high-precision results, with an error of generally less than ±3.0%, for several glass-ceramics.     

Functional electrolytes: Synergetic effect of electrolyte additives for lithium-ion battery

We have found that certain combinations of specific additives show a very interesting behavior in Li-ion batteries. During the course of investigating further improvements in the performance of the triple-bonded compounds, which we very recently reported, a novel and unique effect of an additive combination was observed. The combination of the triple-bonded compounds and the double-bonded compounds has proven to show a much improved battery performance, especially in cycleability and gas evolution than the case when they are singly used. Especially, the synergetic effect of propargyl methanesulfonate and vinylene carbonate is remarkable. To clarify the synergetic effect, the electrochemical properties of the additives and the electrode analyses were investigated. It is assumed that the higher battery performance of the combination effect resulted not only from the thin and dense SEI on the negative electrode but also from the positive electrode surface co-polymerized film produced by the synergetic decomposition of the additives. We suggest that the keys for producing the synergetic functions are (1) a structural difference in the unsaturated moiety, and (2) a greater difference in the reduction potential.     

A 126.6-mm2 AND-type 512-Mb flash memory with 1.8-Vpower supply

A 512-Mb flash memory, which is applicable to removable flash media of portable equipment such as audio players, has been developed. The chip is fabricated with a 0.18-μm CMOS process on a 126.6-mm² die, and uses a multilevel technique (2 bit/1 cell). The memory cell is AND-type, which is suitable for multilevel operation. This paper reports new techniques adopted in the 512-Mb flash memory. First, techniques for low voltage operation are described. The charge pump, control of pumps, and the reference voltage generator are improved to generate internal voltage stably for multilevel flash memory. Next, a method for reducing total memory cost in the removable flash media is described. A new operation mode named read-modify-write is introduced on the chip. This feature makes the memory system simple, because the controller does not have to track sector-erase information     

Hyperfluorescence™: Excel the performance,create the future

Hyperfluorescence™ (HF), known as the most advanced OLED emitting technology, combines TADF and fluorescence mechanisms enabling 100% internal quantum efficiency (IQE) and narrowband emission. Based on in silico simulation, HF is not only more outperformed than the modern OLED emitting technologies but also feasible for the RGB definition of BT.2020. Of the green top-emission HF device, the device performance is manifold increased than that of the bottom-emission, where this effect is more amplified than that in phosphorescence system. An efficiency improvement approach to reach market requirements was illustrated to show our vision in pursuing excellent performance.     

Diffusion and clearance of superparamagnetic iron oxide nanoparticles infused into the rat striatum studied by MRI and histochemical techniques

The purpose of the present study was to investigate, by MRI and histochemical techniques, the diffusion and clearance abilities of superparamagnetic iron oxide nanoparticles (SPION) coated with dextran (Dextran-SPION) and gold (Au-SPION) following their local infusions into the rat brain. In separate groups of anesthetized rats, the Dextran-SPION and Au-SPION were infused at concentrations of 0.01, 0.1, 1 and 5 μg Fe/0.5 μl and at the flow rate of 0.5 μl min(-1) into the left and right striata, respectively. Repetitive T2-weighted spin-echo MRI scans were performed at time intervals of 1, 6, 12, 24, 48, 72 h, and one, two and eight weeks after inoculation. Following infusion of Dextran-SPION (0.1 μg and 1 μg Fe), the maximal distribution volume was observed at about 12-24 h after inoculation and two weeks later the Fe signals were undetectable for the lower dose. On the other hand, Au-SPION remained tightly localized in the closest vicinity of the infusion site as revealed by unchanged MRI signal intensities and strong histochemical staining of Fe(2+) and Fe(3+) ions in the corresponding brain slices. Immunohistochemical staining of astrocytic and microglial reactions revealed that there were no marked differences in GFAP, VIM or OX-42 labeling observed between the nanoparticle types, however the astrocytic reaction was more pronounced in rats receiving nanoparticles compared to the control (aCSF-infused) rats. In conclusion, the present data demonstrate that the viral-sized Dextran-SPION were able to diffuse freely through the interstitial space of the brain being progressively cleared out from the infusion site within two weeks. Thus, Dextran-SPION could be beneficially used in MRI-guided diagnostic applications such as in experimental oncology or as labels and carriers for targeted drug delivery, whereas Au-SPION could be used for labeling and tracking the transplanted stem cells in experimental MRI.     

Effects of annealing ambient on ferroelectric properties and surface chemistry of sol–gel derived Bi3.25La0.75Ti3O12 thin films

In this work, Bi_3.25La_0.75Ti₃O₁₂ (BLT) thin films were prepared by sol–gel coatings followed by rapid thermal annealing in Ar or O₂ ambient. The correlation among annealing ambient, ferroelectric characteristics and surface chemistry of the BLT thin films were investigated. The BLT thin film annealed in Ar showed weaker crystallization, less dense surface and smaller polarization value than that annealed in O₂. After 10⁹ cycles, the remnant polarization of the BLT film annealed in Ar decreased to 83.5 % of the initial value while it remained 89.5 % for the sample annealed in O₂. X-ray photoelectron spectroscopy results indicated the inferior fatigue characteristics of the sample annealed in Ar was the comprehensive result of oxygen vacancies vicinity to Bi and Ti ion in the thin film.     

Hybrid White Light Emitting Diode Based on Silicon Nanocrystals

A novel design of white light emitting diodes (WLEDs) emerges to meet the growing global demand for resource sustainability while preserving health and environment. To achieve this goal, a facile method is developed for the chemical synthesis of a luminescent silicon nanocrystal (ncSi) with a large Stokes shift between absorption and emission. The WLED is prepared by a simple spin‐coating method, and contains a hybrid‐bilayer of the ncSi and luminescent polymer in its device active region. Interestingly, a well‐controlled ultrathin ncSi layer on the polymer makes possible to recombine electrons and holes in both layers, respectively. Combining red and blue‐green lights, emitted from the ncSi and the polymer layers, respectively, produces the emission of white electroluminescence. Herein, a hybrid‐WLED with a sufficiently low turn‐on voltage (3.5 V), produced by taking advantages of the large Stokes shift inherent in ncSi, is demonstrated.