Development of a novel emitting vinyl polymer and its application in organic electroluminescent devices

Abstract— A novel emitting vinyl polymer, poly[4‐(7‐{4‐[N,N‐bis(9,9‐dimethylfluoren‐2‐yl)amino]phenyl}‐2,1,3‐benzothiadiazol‐4‐yl)phenylethylene] (PVFABT), was designed and synthesized. The new vinyl polymer was found to form smooth amorphous films with a high glass‐transition temperature of 199°C. The polymer possesses bipolar character with both electron‐donating and accepting properties. It undergoes reversible anodic oxidation and cathodic reduction to give stable cation and anion radicals. It exhibits intense orange fluorescence in solution and as film. A multilayer organic electroluminescent device using PVFABT as an emitting material emitted orange light, exhibiting high performance.     

Production and performance of the inFOCmicroS 20-40-keV graded multilayer mirror

The International Focusing Optics Collaboration for microCrab Sensitivity (InFOCmicroS) balloonborne hard x-ray telescope incorporates graded Pt/C multilayers replicated onto segmented Al foils to obtain the significant effective area at energies previously inaccessible to x-ray optics. Reflectivity measurements of individual foils demonstrate our capability to produce a mass quantity of multilayered foils with a rms roughness of 0.5 nm. The effective area of the completed mirror is 78 and 22 cm2 at 20 and 40 keV, respectively. The measured half-power diameter is 2.0 +/- 0.6 are min (90% confidence). The successful completion of this mirror demonstrates its applicability to future x-ray telescopes such as Constellation-X.     

Speech recognition in living rooms: Integrated speech enhancement and recognition system based on spatial,spectral and temporal modeling of sounds

Research on noise robust speech recognition has mainly focused on dealing with relatively stationary noise that may differ from the noise conditions in most living environments. In this paper, we introduce a recognition system that can recognize speech in the presence of multiple rapidly time-varying noise sources as found in a typical family living room. To deal with such severe noise conditions, our recognition system exploits all available information about speech and noise; that is spatial (directional), spectral and temporal information. This is realized with a model-based speech enhancement pre-processor, which consists of two complementary elements, a multi-channel speech–noise separation method that exploits spatial and spectral information, followed by a single channel enhancement algorithm that uses the long-term temporal characteristics of speech obtained from clean speech examples. Moreover, to compensate for any mismatch that may remain between the enhanced speech and the acoustic model, our system employs an adaptation technique that combines conventional maximum likelihood linear regression with the dynamic adaptive compensation of the variance of the Gaussians of the acoustic model. Our proposed system approaches human performance levels by greatly improving the audible quality of speech and substantially improving the keyword recognition accuracy.     

Recent situation of industrial implementation of Cat-CVD technology in Japan

Efforts of industrial application of Cat-CVD technology are surveyed. Recent movement of industrial implementation is also reviewed by showing examples in Japanese industry. Cat-CVD technology is originally developed as a new tool for fabricating semiconductor devices, however, recently, use of the technology is attempted in various fields such as chemical, mechanical and bio-technical engineering. It is shown that Cat-CVD has high feasibility as a fundamental technology of modern industries.     

SOLUBILITY IN ORGANIC DILUENTS AND EXTRACTION BEHAVIOR OF CALIX[4]ARENE CARBOXYLATES WITH DIFFERENT ALKYL CHAINS

ABSTRACT

Two types of alkylcalix[4]arene carboxylates with different alkyl chains, together with three types with the same alkyl chains were synthesized to investigate their solubility in four different organic diluents. The solubility was found to be enhanced by using the calixarene compounds with longer alkyl chains and by using mixtures of compounds with different alkyl chains. The order of solubility in the different organic diluents was found to be:

chloroform > toluene ? EXXSOL D80 ≈ hexane.

The stoichiometry of the copper complex with the compounds having the same alkyl chains was also determined and the maximum loading capacity of copper with each extractant was estimated.     

An EDTA-associated anti-B agglutinin: the role of ionized calcium

BACKGROUND: It is believed that EDTA-dependent panagglutination is associated with free carboxylic acids that support reactions of rare autoagglutinins. CASE REPORT: An ABO typing discrepancy occurred in an 88-year-old patient. The specificity of his autoagglutinin was demonstrated by panel cell study and absorption tests using normal donors' red cells or immunoadsorbents coated with A, B, or O substances. Inhibition assays were performed to determine whether the autoagglutinin was inhibited by ionized calcium or carboxylic acids. The autoagglutinin had anti-B specificity when tested in the presence of EDTA. It was neutralized by group B secretor saliva and adsorbed by crystalline silica coated with simple B substances with or without EDTA, although it was absorbed by group B red cells only in the presence of EDTA. The agglutinating activity was stronger at 25 degrees C (titer 64) than at 37 degrees C (titer 16) and was destroyed by treatment of the serum with dithiothreitol, which suggests that the autoagglutinin is IgM. This activity also appeared in the patient's serum after dialysis and in an eluate obtained after adsorption with simple B substances, and it was inhibited by the addition of CaCl2 at 0.5 mM or higher concentrations. This suggests that the agglutination is not dependent on EDTA but, rather, on the concentration of ionized calcium. The autoagglutinin failed to react with group B red cells treated with glutaraldehyde for 10 minutes. CONCLUSION: An anti-B autoagglutinin was shown to have caused an ABO typing discrepancy in the presence of EDTA. These results suggest that autoagglutination requires an environment with low levels of ionized calcium, but not the presence of carboxyl groups.     

Application of finite fourier transformation for the solution of the diffusion equation

Application of the finite Fourier transformation is discussed for the solution of the diffusion equation in one dimension, two dimensional x-y and triangular geometries. It can be shown that the equation by the Nodal Green's function method in Cartesian coordinate can be derived as a special case of the finite Fourier transformation method.     

Effect of microstructures on dielectric breakdown strength of sintered reaction-bonded silicon nitride ceramics

Silicon nitride (Si₃N₄) was prepared from silicon by a sintered reaction-bonded silicon nitride method using yttria and magnesia as sintering additives. Post-sintering (PS) of nitrided compacts was carried out at 1850°C under a nitrogen pressure of 1 MPa. Effect of PS time on microstructure and dielectric breakdown strength (DBS) of the prepared Si₃N₄ ceramics was evaluated. The DBS was measured using specimens with four different thicknesses (0.30, 0.20, 0.10, and 0.05 mm) in order to examine the thickness dependence. The porosity of the sintered Si₃N₄ decreased by prolonging the PS time, and the full density could be achieved at the PS time of over 6 h. After full densification, rod-like β-Si₃N₄ grains grew up, and their maximum grain size increased from 45.1 to 154.7 μm by prolonging the PS time from 6 to 48 h. The DBS of the thick Si₃N₄ substrates (0.30 mm) showed little variation from 35.4 to 47.0 kV/mm, regardless of the PS time. On the other hand, that of the thin ones (0.05 mm) dramatically decreased from 99.5 to 9.8 kV/mm with increased the PS time from 6 to 48 h. Because the DBS sharply decreased at the thin substrate sintered for longer time in which some large-elongated grains might span the substrate thickness-wise throughout, it was inferred that the interface between β-Si₃N₄ grains and grain boundary phase/intergranular glassy films might be a path of the dielectric breakdown.     

Development of a strain for efficient degradation of polychlorinated biphenyls by patchwork assembly of degradation pathways

Rhodococcus jostii RHA1 accumulates chlorobenzoates (CBA) during the degradation of polychlorinated biphenyls (PCBs). CBA degradation is considered one of the rate-limiting steps in the complete degradation of PCBs. To reduce the accumulation of CBAs, the upper pathway enzyme genes for PCB degradation of RHA1 were introduced into a CBA-degrading bacterium, Burkholderia sp. NK8. The resulting recombinant strain exhibited no biphenyl 2,3-dioxygenase (BphA) activity encoded by bphAaAbAcAd genes, which encode the large and small subunits of the terminal oxygenase component and the ferredoxin and reductase subunits responsible for electron transfer from NADH to the large subunit. The remaining enzyme genes involved in the transformation of biphenyl to benzoate, bphB2C1D1, which encode dehydrogenase, ring-cleavage dioxygenase and hydrolase, conferred activities to NK8. To obtain the BphA activity of RHA1 in NK8, sets of BphA genes were constructed by combining the bphAaAbAcAd genes of RHA1 and bphA3A4 of Pseudomonas pseudoalcaligenes KF707, encoding the ferredoxin and reductase subunits. Hybrid derivatives of BphA containing the KF707 bphA3 conferred BphA activity to NK8, and a derivative containing the RHA1 bphAaAb and KF707 bphA3A4 genes exhibited the highest BphA activity. A plasmid containing the RHA1 bphAaAb and KF707 bphA3A4 genes plus the RHA1 bphB2C1D1 genes was constructed and introduced into NK8. The resulting recombinant strain efficiently degraded 2-, 3- and 4-chlorobiphenyls with an apparent reduction in CBA accumulation in comparison to the recombinant mutant strain, which had an insertion in the cbeA gene to inactivate CBA dioxygenase.