High-Density Polyethylene(HDPE) Surface Treatment Using an RF Capacitive Atmospheric Pressure Cold Ar Plasma Jet

In this study,a high-density polyethylene（HDPE,5-mm-thick,0.95 g/cm3） surface was treated using an RF capacitive atmospheric pressure cold Ar plasma jet.By using this Ar plasma jet,a hydrophilic HDPE surface was formed during the plasma treatment.In particular, the effects of an additive gas（N₂ or O2） on the HDPE surface treatment were investigated in detail.It was shown that the addition of N2 or O2 gas had an important influence on the HDPE surface treatment.Compared to pure Ar plasma treatment,a lower value of water contact angle （WCA） was obtained when a trace of N2 or O2 gas was added.It was also found that besides the quantities of active species in the plasma jet,the treatment temperature played an important role in the HDPE surface treatment.This is because surface molecular motion is not negligible when the treatment temperature is close to the melting point of the polymer.     

Organic field-effect transistors using liquid crystalline compound synthesized to enhance carrier-transport ability

We report the characteristics of organic field-effect transistors (OFETs) using the liquid crystalline compound synthesized to enhance carrier-transport ability. Oblique evaporation with a tilt angle of 60° and subsequent thermal annealing at 200 °C yielded anisotropic carrier transport due to the anisotropic molecular alignment. The OFETs fabricated with polymethylmethacrylate (PMMA) intermediate layers showed mobility up to 2.6 × 10^?2 cm²/V s. The characteristics of OFETs depended on the deposition rate of liquid crystalline materials. The mobilities increased with decrease in the deposition rate. Polarization-resolved photoluminescence (PL) measurements exhibited that the molecular orientation in liquid crystalline films was improved with decrease in the deposition rate. Therefore it is assumed that the carrier-transport properties were enhanced by improving the molecular orientation in the liquid crystalline films.     

Characterization of Schottky barrier diodes on a 0.5-inch single-crystalline CVD diamond wafer

In this study, Schottky barrier diodes were fabricated on a 0.5-inch single-crystalline diamond wafer, and the quality of the wafer as well as the performance of the devices were characterized. A rocking curve map indicated that the FWHM of the central 8 × 8-mm region was 10–50 arc sec, which is similar to that of high-quality HPHT single-crystalline diamond. The fabricated pVSBDs on the p^?/p⁺ stacked layer showed a high operation limit for the electrical field, with the mean value of this limit being higher than 2.5 MV/cm when the electrode was smaller than 300 µm. The performance of the devices seemed to be associated with the quality of the wafer. This indicates that the leakage current of a device is determined by the quality of the diamond wafer on which it is fabricated.     

Thermal comfort and productivity - Evaluation of workplace environment in a task conditioned office

The environment of workplace in an office involved in creative work was evaluated in 2005 and 2006. The M Company has installed partition based task/ambient conditioning systems (TAC) and several environment-friendly systems, such as double-skin and thermal-storage structures. It was intended to investigate the influence of the worker's behavior and task conditioning on worker's thermal comfort and productivity. In this survey, immediate thermal environment and worker's behavior were measured, and occupants' surveys of thermal comfort and feeling of fatigue were conducted. We found that both activity level of occupant and exposed thermal environment is greatly different one by one. It is suggested that an increase in metabolic rate according to worker's behavior influenced on their thermal comfort. Based on the knowledge obtained from this investigation, needs for TAC are discussed.     

Transition-Metal-Catalyzed Highly Regio- and Stereoselective Co-Polymerization of Dialkynylbenzene with Benzenedithiol Leading to Poly（Phenylene Vinylene Sulfide）

Co-polymerization of dialkynylbenzene with benzenedithiol proceeds regio- and stereoselectively in the presence of transition metal catalysts, affording the corresponding poly（phenylene vinylene sulfide） in good yield. In the presence of palladium acetate as catalyst, Markovnikov addition takes place selectively, whereas chlorotris（triphenylphosphine）rhodium-catalyzed reaction affords anti-Markovnikov adduct with excellent regio- and stereoselectivity.     

Method to measure refractive indices of small nonspherical particles: Application to black carbon particles

We demonstrate a new method to measure refractive indices m of small nonspherical particles by simultaneous measurement of particle volume and light-scattering cross section. In contrast to traditional methods, this method can suppress uncertainties due to unknown particle shape. As demonstration of the method, laboratory experiments using an aerosol particle mass analyzer (APM) and single-particle soot photometer (SP2) have been conducted to determine the refractive indices of seven types of commercial black carbon particles and ambient soot at 1064 nm wavelength. Difference in measured |(m²?1)/(m²+2)| values among the seven commercial black carbon samples is consistent with the difference in their crystalline structures identified by a transmission electron microscope. The complex refractive index m=(n, k) of ambient soot particles in Tokyo urban area was determined to be m=(2.26±0.13, 1.26±0.13).     

Hemopexin as biomarkers for analyzing the biological responses associated with exposure to silica nanoparticles

Practical uses of nanomaterials are rapidly spreading to a wide variety of fields. However, potential harmful effects of nanomaterials are raising concerns about their safety. Therefore, it is important that a risk assessment system is developed so that the safety of nanomaterials can be evaluated or predicted. Here, we attempted to identify novel biomarkers of nanomaterial-induced health effects by a comprehensive screen of plasma proteins using two-dimensional differential in gel electrophoresis (2D-DIGE) analysis. Initially, we used 2D-DIGE to analyze changes in the level of plasma proteins in mice after intravenous injection via tail veins of 0.8 mg/mouse silica nanoparticles with diameters of 70 nm (nSP70) or saline as controls. By quantitative image analysis, protein spots representing >2.0-fold alteration in expression were found and identified by mass spectrometry. Among these proteins, we focused on hemopexin as a potential biomarker. The levels of hemopexin in the plasma increased as the silica particle size decreased. In addition, the production of hemopexin depended on the characteristics of the nanomaterials. These results suggested that hemopexin could be an additional biomarker for analyzing the biological responses associated with exposure to silica nanoparticles. We believe that this study will contribute to the development of biomarkers to ensure the safety of silica nanoparticles.     

Binary-decision-diagram device

The device proposed here for future LSI's is based on a concept different from the Boolean equations usually used for representing digital functions. The unit function of this device is simple two-way switching and can be implemented utilizing various physical effects, such as optical switching, electron-wave modulation, and single-electron transport. Several possible device structures are presented, and a simulated result for a single-electron device is described