Organic light emitting bistable memory device with Cs doped electron transport layer

Dual functional organic light emitting bistable memory devices (OLEBDs) were developed by using a Cs doped electron transport layer. Bistability was exhibited by Cs doping in 4,7-diphenyl-1,10-phenanthroline (Bphen) and the driving voltage was lowered by alkali metal doping. n-type doping effect of Cs with Bphen induced the electrical switching behavior in OLEBDs and a low driving voltage. A high on/off ratio over 1000 could be obtained in Cs doped OLEBDs and it was kept stable during multicycle measurements. OLEBDs showed superior performances both as a memory and a light emitting device.     

Improved efficiency in organic solar cells through fluorinated interlayer induced crystallization

A hydrophobic fluorinated polymer material, polyvinylidenefluoride (PVDF), was used as an interlayer between the poly-3,4-ethylenedioxythiophene:polystyrenesulfonate and poly(3-hexylthiophene)(P3HT):[6,6]-phenyl C61-butyric acid methyl ester (PCBM) active layers in organic solar cells (OSCs). The PVDF interlayer increased the short circuit current and improved the power conversion efficiency of the OSCs. The PVDF interlayer induced extensive crystallization of the P3HT:PCBM active layer during thermal treatment, which was responsible for the high short circuit current and power conversion efficiency.     

Automatic Word Spacing Using Probabilistic Models Based on Character n-grams

On the Internet, information is largely in text form, which often includes such errors as spelling mistakes. These errors complicate natural language processing because most NLP applications aren't robust and assume that the input data is noise free. Preprocessing is necessary to deal with these errors and meet the growing need for automatic text processing. One kind of such preprocessing is automatic word spacing. This process decides correct boundaries between words in a sentence containing spacing errors, which are a type of spelling error. Except for some Asian languages such as Chinese and Japanese, most languages have explicit word spacing. In these languages, word spacing is crucial to increase readability and to accurately communicate a text's meaning. Automatic word spacing plays an important role not only as a spell-checker module but also as a preprocessor for a morphological analyzer, which is a fundamental tool for NLP applications. Furthermore, automatic word spacing can serve as a postprocessor for optical-character-recognition systems and speech recognition systems     

Miniaturized CBCPW bandpass filter basedon thin film polyimide on lossy silicon

This letter reports a miniaturized conductor-backed coplanar waveguide (CBCPW) bandpass filter (BPF) based on a thin film polyimide layer coated on a lossy silicon. With a 20-/spl mu/m-thick polyimide interface layer and back metallization, the interaction of electromagnetic fields with the lossy silicon substrate has been isolated, and as a result low-loss and low-dispersive CBCPW line has been obtained. The measured attenuation at 20GHz is below 1.2dB/cm, which is comparable with the CPW fabricated on GaAs. In addition, by using the proposed CBCPW geometry, a miniaturized Ku-band BPF was designed and its measured frequency response demonstrated excellent correlation with the predicted value which validated the performance of the proposed CBCPW geometry used for radio frequency integrated circuit interconnects and filter applications.     

Enhancement of collection efficiency of inertial impactors using elliptical concave impaction plates

In this study, elliptical concave impaction plate was suggested for lowering cut-off size and therefore enhancing collection efficiency of the inertial impactor. Statistical Lagrangian Particle Tracking (SLPT) model was employed for calculating impactor collection efficiency and validated by comparing with the experimental data of Tsai, C.J., Cheng, Y.H. ((1995). Solid particle collection characteristics on impaction surfaces of different designs. Aerosol Science Technology, 23, 96–106), for three different shapes of impaction plates. Then, the effect of the ratio of major axis length (A) to minor axis length (B) for determining the curvature of elliptical concave impaction plate, on impactor collection efficiency was numerically investigated using the SLPT model, with nozzle Reynolds numbers ranging from 1440 to 2600. It was found that there existed an optimum range of the A/B ratio for minimizing the cut-off size, i.e. the A/B ratio ranged between 3.2 and 4.2 for the PM10 inertial impactor, or between 3.2 and 3.5 for the PM2.5 inertial impactor. When the elliptical concave impaction plates with the A/B ratio of 4.0 and 3.5 were applied to the MST indoor air sampling impactor having PM10 and PM2.5 stages, the cut-off size was predicted to decrease from 10 to 6.5 μm and from 2.5 to 1.6 μm, respectively, while the impactor collection efficiency curves became less steep.     

Effects of gamma radiation on sensory qualities, microbiological and chemical properties of salted and fermented squid

The effects of gamma radiation on sensory quality, microbial population, and chemical properties of salted and fermented squid were investigated. Squid (Todarodes pacificus) was sliced, washed, and then salted with 5, 10, and 20% (wt/wt) sodium chloride. Salted squid was irradiated with dosages of 0, 2.5, 5.0, and 10 kGy of gamma radiation and fermented at 15 degrees C for 50 days. Proximate composition, salinity, water activity, sensory evaluation, and total microbiological populations were examined. Chemical analyses providing information on degree of fermentation, such as amino nitrogen (AN), volatile basic nitrogen (VBN), trimethylamine (TMA), and hypoxanthine (Hx) were also conducted. Irradiated squid was not different in proximate composition, salinity, and water activity from nonirradiated squid. Sensory evaluation scores, total bacteria populations, and pH values were variable depending on salt concentration and irradiation dose. During fermentation, AN, VBN, TMA, and Hx contents increased rapidly as the salt concentration and irradiation dose decreased. Specifically, these chemical compounds of salted and fermented squid prepared with 10% salt and 10 kGy of gamma radiation maintained the appropriate level of fermentation. The present results showed that the combination of low salt concentration (10%) and gamma radiation was effective in processing salted and fermented squid and extending its shelf life compared to control (20% of salt) without adding any food additives.     

Deposition of TiN films on Co–Cr for improving mechanical properties and biocompatibility using reactive DC sputtering

This study reports the deposition of TiN films on Co–Cr substrates to improve the substrates’ mechanical properties and biological properties. In particular, the argon to nitrogen (Ar:N₂) gas flow ratio was adjusted to control the microstructure of the TiN films. A Ti interlayer was also used to enhance the adhesion strength between the Co–Cr substrate and TiN films. A series of TiN films, which are denoted as TiN-(Ar/N₂)1:1, Ti/TiN-(Ar/N₂)1:1, and Ti/TiN-(Ar:N₂)1:3, were deposited by reactive DC sputtering. All the deposited TiN films showed a dense, columnar structure with a preferential orientation of the (200) plane. These TiN films increased the mechanical properties of Co–Cr, such as the critical load during scratch testing, hardness, elastic modulus and plastic resistance. In addition, the biological properties of the Co–Cr substrates, i.e. initial attachment, proliferation, and cellular differentiation of the MC3T3-E1 cells, were improved considerably by deposition of the TiN films. These results suggest that TiN films would effectively enhance both the mechanical properties and biocompatibility of biomedical Co–Cr alloys.     

High efficiency deep blue phosphorescent organic light-emitting diodes

Deep blue phosphorescent organic light-emitting diodes have been developed by using tris((3,5-difluoro-4-cyanophenyl)pyridine) iridium (FCNIr) as a blue phosphorescent dopant. The FCNIr showed a wide triplet bandgap of 2.8 eV for deep blue emission due to a strong electron withdrawing CN substituent in addition to F unit. Doping of the FCNIr in N,N’-dicarbazolyl-3,5-benzene gave a high quantum efficiency of 9.2% with a CIE color coordinate of (0.15, 0.16).     

Low driving voltage in organic light-emitting diodes using MoO3 as an interlayer in hole transport layer

Driving voltage of organic light-emitting diodes (OLEDs) was lowered by applying MoO₃ as an interlayer between hole injection layer (HIL) and hole transport layer (HTL). MoO₃ was effective as an interlayer between HIL and HTL due to its valence band of around 5.3 eV which is suitable for hole injection. Hole injection from HIL to HTL was enhanced by MoO₃ interlayer and driving voltage of green fluorescent device could be lowered by 1.3 V at 1000 cd/m² by using thin MoO₃ interlayer.