Characteristics of polyvinylpyrrolidone-layered silicate nanocomposites prepared by attrition ball milling

Polyvinylpyrrolidone (PVP)/sodium montmorillonite (MMT) nanocomposites prepared via the solution intercalation method were investigated by UV/vis, SEM, X-ray diffraction, TEM, FT-IR and PLM (polarized light microscopy). PVP/MMT nanocomposites show exfoliation below 20 wt% MMT and intercalation above this concentration. Nanocomposites retain good optical clarity and increased thermal resistance with MMT content. The compatibility between PVP and MMT and their enhanced properties may be explained by hydrogen bonding interactions. In addition, the nanocomposites prepared under more rigorous mixing conditions show better transparency because the smaller particle sizes are induced. In addition, the study on optically clear PVP/MMT suspensions helps one to understand how optical anisotropy of MMT is affected by the existence of polymer in aqueous solution.     

Methyl tert-butyl ether decomposition over heteropoly acid catalyst in a cellulose acetate membrane reactor

In this study the methyl tert-butyl ether (MTBE) decomposition over H₃PW₁₂O₄₀ was carried out in a cellulose acetate membrane reactor. The permeability of methanol through the cellulose acetate membrane was about 30 and 300 times higher than that of either isobutene or MTBE, respectively. The isobutene selectivity in the fixed bed reactor was only slightly higher than the methanol selectivity due to the side reaction. In the cellulose acetate membrane reactor, however, the isobutene selectivity in the rejected stream was 68% and the methanol selectivity in the permeated stream was up to 97%. The MTBE conversion in the membrane reactor was about 7% higher than that in the membrane-free fixed bed reactor under the same reaction conditions. The enhanced performance of the membrane reactor in this reversible reaction was mainly due to the selective permeation of methanol which resulted in a methanol-deficient condition suppressing MTBE synthesis reaction.     

Preparation and characterizations of interpenetrating polymer network hydrogels of poly(ethylene oxide) and poly(methyl methacrylate)

Interpenetrating polymer network (IPN) hydrogels based on poly(ethylene oxide) and poly(methyl methacrylate) were prepared by radical polymerization using 2,2‐dimethyl‐2‐phenylacetophenone and ethylene glycol dimethacrylate as initiators and crosslinkers, respectively. The IPN hydrogels were analyzed for sorption behavior at 25°C and at a relative humidity of 95% using dynamic vapor sorption. The IPN hydrogels exhibited a relatively high equilibrium water content in the range of 13–68%. The state of water in the swollen IPN hydrogels was investigated using differential scanning calorimetry. The free water in the hydrogels increased as the hydrophilic content increased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 258–262, 2003     

Investigation of electrically conductive acrylonitrile‐butadiene rubber

Electrically conductive acrylonitrile‐butadiene rubbers (NBRs) containing carbon black (CB) as conductive filler were prepared in order to investigate their electrical and mechanical properties. The effects of conductive CB loading, temperature, acrylonitrile content, crosslinking density of vulcanizates, and plasticizer on conductivity were studied. The change in electrical conductivity of NBRs with different amounts of CB showed that there is a certain critical point (percolation threshold) where a significant decrease in electrical resistivity (increase in conductivity) is observed. Mechanical properties such as tensile strength, elongation to break, and surface hardness of vulcanized NBRs were measured. It was found that the percolation threshold was 5 phr of CB for the NBR/CB composites. J. VINYL ADDIT. TECHNOL., 13:71–75, 2007. © 2007 Society of Plastics Engineers.     

Boron distribution in a low-alloy steel

Boron distribution in a low-alloy steel (15B26:0.25C-0.29Cr-0.03Ti-0.028Al-0.0016B) has been characterized employing Fission Track Etching (FTE) method. The characteristics of boron distribution with variation of cooling rate after austenitization and through case-hardened depth after carburization were analyzed. Hardenability of 15B26 steel was also evaluated through Jominy-end-quench test and the results are as follows: It was observed that, in austenitized 15B26 steel, boron was distributed uniformly over the whole area of specimen with a little segregation along the austenite grain boundaries at higher cooling rates and boron precipitates were formed in the intergranular as well as transgranular regions at lower cooling rates. Jominy equivalents (HRC 35) of 15B26 steel were fairly increased between the Jominy temperatures of 820°C and 850°C, which might result from the increase of the amount of soluble boron in austenite due to the dissolution of borocarbides between 820°C and 850°C. In carburized 15B26 steel, the different through thickness features of boron distribution from the carburized surface were found; coarse nodular boron precipitates up to the depth of 150 μm; uniform distribution of dissolved boron between 150~650 μm; and segregation of boron atoms along grain boundaries in the regions deeper than 650 μm.     

Page segmentation using minimum homogeneity algorithm and adaptive mathematical morphology

Document layout analysis or page segmentation is the task of decomposing document images into many different regions such as texts, images, separators, and tables. It is still a challenging problem due to the variety of document layouts. In this paper, we propose a novel hybrid method, which includes three main stages to deal with this problem. In the first stage, the text and non-text elements are classified by using minimum homogeneity algorithm. This method is the combination of connected component analysis and multilevel homogeneity structure. Then, in the second stage, a new homogeneity structure is combined with an adaptive mathematical morphology in the text document to get a set of text regions. Besides, on the non-text document, further classification of non-text elements is applied to get separator regions, table regions, image regions, etc. The final stage, in refinement region and noise detection process, all regions both in the text document and non-text document are refined to eliminate noises and get the geometric layout of each region. The proposed method has been tested with the dataset of ICDAR2009 page segmentation competition and many other databases with different languages. The results of these tests showed that our proposed method achieves a higher accuracy compared to other methods. This proves the effectiveness and superiority of our method.     

Exaggerating Character Motions Using Sub‐Joint Hierarchy

Motion capture cannot generate cartoon‐style animation directly. We emulate the rubber‐like exaggerations common in traditional character animation as a means of converting motion capture data into cartoon‐like movement. We achieve this using trajectory‐based motion exaggeration while allowing the violation of link‐length constraints. We extend this technique to obtain smooth, rubber‐like motion by dividing the original links into shorter sub‐links and computing the positions of joints using Bézier curve interpolation and a mass‐spring simulation. This method is fast enough to be used in real time.     

A Hidden‐picture Puzzles Generator

A hidden‐picture puzzle contains objects hidden in a background image, in such a way that each object fits closely into a local region of the background. Our system converts image of the background and objects into line drawing, and then finds places in which to hide transformed versions of the objects using rotation‐invariant shape context matching. During the hiding process, each object is subjected to a slight deformation to enhance its similarity to the background. The results were assessed by a panel of puzzle‐solvers.     

A study of roll‐printing technology for TFT‐LCD fabrication

Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used.     

Electron‐beam deposition of MgO on plastic substrate and manufacturing flexible flat fluorescent lamp

Abstract— A flexible fluorescent lamp that utilizes the same plasma discharge mode as in PDPs has been manufactured. The structure of the flexible lamp is simple and easy to manufacture. All‐plastic materials including plastic substrates, barrier ribs (spacers), and sealants for low‐temperature manufacturing processing have been adopted except for the phosphor and MgO thin film. The MgO thin films were coated on the plastic substrates as a protection layer against the plasma discharge. The adhesion and biaxial texture of MgO thin film deposited on the plastic substrates, poly‐ethyle‐nenaphthalate (PEN) and polycarbonate (PC), at low temperature (100–180°C) has been characterized. The MgO film on PEN shows good adhesion under a repeated bending test. The manufactured flexible lamp consists of two plastic substrates of about 3 in. on the diagonal, barrier rib (spacer), and external ITO electrodes. The Ne‐Xe (5%) gas mixture at 100–200 Torr was used for the discharge gas. A maximum surface luminance of about 100 cd/m² was achieved for a 1 ‐kHz AC pulse.