Development of a high‐resolution RGBW flexible display using a white organic light‐emitting diode with microcavity structure and that of a side‐roll touch panel

In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen.     

Aging and availability of binocular disparity and pictorial depth cues in 3D graphics contents

Some stereoblind observers do not perceive depth of 3D stimuli that depends on binocular disparity. These individuals, who have no disabilities, comprise over 5% of the general population. In addition, 17–30% of nonstereoblind young and young–middle people do not use disparity information in certain 3D environments, a phenomenon known as pseudo‐stereoblindness. This study aimed to investigate the relationship between aging and the proportion of pseudo‐stereoblindness in the general population. In an experiment, 134 nonstereoblind participants, ranging in age from 17 to 83 years, judged subjective depth of 3D stimuli containing binocular disparity and pictorial depth cues. Results showed that the proportion of pseudo‐stereoblindness among young (17–24 years old) and young–middle aged observers (25–39 years old) was 29%, in both cases. However, the proportion of pseudo‐stereoblind observers increased in older populations: 65% and 82% in the middle (40–54 years old) and senior (55–83 years old) age groups, respectively. These results suggest that a number of people, especially in elderly populations, have trouble perceiving depth from binocular disparity in 3D graphic contents despite their essential ability to use disparity information.     

Effect of vibration on eye,head and helmet movements while wearing a helmet‐mounted display

Previous research has demonstrated a loss of helmet‐mounted display (HMD) legibility for users exposed to whole body vibration. A pair of human factors studies was conducted to evaluate the effect of whole body vibration on eye, head, and helmet movements for seated users of a HMD while conducting simple fixation and smooth pursuit tracking tasks. These experiments confirmed that vertical eye motion can be demonstrated, that is consistent with the human visual systems' response to the vestibular–ocular reflex (VOR). Helmet slippage was also shown to occur, which could exacerbate loss of display legibility. The largest amplitudes in eye movements were observed during exposure to sinusoidal vibration in the 4–6 Hz range, which is consistent with the frequencies that past research has associated with whole‐body resonance and the largest decrease in display legibility. Further, the measured eye movements appeared to be correlated with both the angular acceleration of the user's head and the angular slippage of the user's helmet. This research demonstrates that the loss of legibility while wearing HMDs likely results from a combination of VOR‐triggered eye movements and movement of the display. Future compensation algorithms should consider adjusting the display in response to both VOR‐triggered eye and HMD motion.     

Synthesis and physicochemical characterization of amphiphilic block copolymer self‐aggregates formed by poly(ethylene glycol)‐block‐poly(ϵ‐caprolactone)

Diblock copolymers with different poly(ε‐caprolactone) (PCL) block lengths were synthesized by ring‐opening polymerization of ε‐caprolactone in the presence of monomethoxy poly(ethylene glycol) (mPEG‐OH, MW 2000) as initiator. The self‐aggregation behaviors and microscopic characteristics of the diblock copolymer self‐aggregates, prepared by the diafiltration method, were investigated by using ¹H NMR, dynamic light scattering (DLS), and fluorescence spectroscopy. The PEG–PCL block copolymers formed the self‐aggregate in an aqueous environment by intra‐ and/or intermolecular association between hydrophobic PCL chains. The critical aggregation concentrations of the block copolymer self‐aggregate became lower with increasing hydrophobic PCL block length. On the other hand, reverse trends of mean hydrodynamic diameters were measured by DLS owing to the increasing bulkiness of the hydrophobic chains and hydrophobic interaction between the PCL microdomains. The partition equilibrium constants (K_v) of pyrene, measured by fluorescence spectroscopy, revealed that the inner core hydrophobicity of the nanoparticles increased with increasing PCL chain length. The aggregation number of PCL chain per one hydrophobic microdomain, investigated by the fluorescence quenching method using cetylpyridinium chloride as a quencher, revealed that 4–20 block copolymer chains were needed to form a hydrophobic microdomain, depending on PCL block length. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3520–3527, 2006     

Preparation and Kinetic Considerations for the Dissolution of Cr‐substituted Iron Oxides in Reductive‐complexing Formulations

The dissolution rate coefficients of Cr‐substituted (0‐20 at.% Cr) iron oxides viz. hematite and magnetite were determined by using an inverse cubic rate (ICR) law applicable for spherical particles as well as by a general kinetic equation (GKE) applicable for polydispersed particles. An attempt is made to compare both the treatments for different kinds of dissolution profiles obtained by employing oxides with narrow particle size distribution in V(II)‐EDTA and citric acid‐EDTA‐ascorbic acid formulations at 353±5K. The dissolution profiles could be classified into three types based on the nature of oxide and formulations. It is observed that both ICR and GKE treat the dissolution course as a function of decrease in fraction of undissolved mass, m/m₀. The dissolution rate coefficients determined by ICR and GKE have shown the similar trend of decrease with increasing Cr content of the oxides and was ascribed to lattice stabilization.     

现代生物工程技术简介

对组成现代生物工程的六大技术系统：基因工程、蛋白质工程、酶工程、细胞工程、微生物工程、生化工程的历史和现状，工作内容及应用前景作了简明的介绍。     

High‐retention properties for Hg(II) ions of a resin containing ammonium and pyridine groups

The metal‐ion uptake behavior of the chelating resin poly([(3‐(methacryloylamino)propyl] trimethyl ammonium chloride‐co‐4‐vinyl pyridine) has been investigated. The resin is obtained by radical copolymerization in a yield of 99.6%. The hydrophilic resin shows a high retention capacity and selectivity toward Hg(II) ions in the presence of Cu(II), Pb(II), Cd(II), Zn(II), and Cr(III) ions. A retention of Hg(II) higher than 99% is observed after 5 min. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2595–2599, 2002     

Effect of low molecular weight polybutadiene as processing aid on properties of silica‐filled styrene–butadiene rubber compounds

Because silica has strong filler–filler interactions, a silica‐filled rubber compound shows a poor filler dispersion compared to a carbon black‐filled one. Improvement of the filler dispersion in silica‐filled styrene–butadiene rubber (SBR) compounds was studied using low molecular weight polybutadiene (liquid PBD) with the high content of 1,2‐unit. By adding the liquid PBD to the silica‐filled SBR compound, the filler dispersion and flow property are improved. The cure time and cure rate become faster as the 1,2‐unit content of the liquid PBD increases for the compounds containing the liquid PBD. The crosslink density increases linearly with increase in the 1,2‐unit content of the liquid PBD. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3135–3140, 2003     

活性炭负载Ti(SO_4)_2催化合成丙二酸二丁酯的研究

首次以活性炭负载硫酸钛 (Ti(SO4) 2 /C)作催化剂 ,合成丙二酸二丁酯 ,此催化剂活性高 ,选择性好 ,易分离 ,不腐蚀设备 ,反应时间短 ,是一种环境友好催化剂。考察了影响酯化反应的条件 ,获得优化工艺条件如下 :Ti(SO4) 2 负载量 2 0 % ,丙二酸 0 2mol,正丁醇 0 6mol,催化剂 0 8g ,反应温度 15 0℃ ,反应时间 90min ,丙二酸的转化率 94 %以上     

Reactivity,chemical structure,and molecular mobility of urea–formaldehyde adhesives synthesized under different conditions using FTIR and solid‐state 13C CP/MAS NMR spectroscopy

This study was conducted to investigate the effects of reaction pH condition and hardener type on the reactivity, chemical structure, and molecular mobility of urea–formaldehyde (UF) resins. Three different reaction pH conditions, such as alkaline (7.5), weak acid (4.5), and strong acid (1.0), were used to synthesize UF resins, which were cured by adding four different hardeners (ammonium chloride, ammonium sulfate, ammonium citrate, and zinc nitrate) to measure gel time as the reactivity. FTIR and ¹³C‐NMR spectroscopies were used to study the chemical structure of the resin prepared under three different reaction pH conditions. The gel time of UF resins decreased with an increase in the amount of ammonium chloride, ammonium sulfate, and ammonium citrate added in the resins, whereas the gel time increased when zinc nitrate was added. Both FTIR and ¹³C‐NMR spectroscopies showed that the strong reaction pH condition produced uronic structures in UF resin, whereas both alkaline and weak‐acid conditions produced quite similar chemical species in the resins. The proton rotating‐frame spin–lattice relaxation time (T_1ρH) decreased with a decrease in the reaction pH of UF resin. This result indicates that the molecular mobility of UF resin increases with a decrease in the reaction pH used during its synthesis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2677–2687, 2003