Effect of filler surface treatment on the properties of recycled high‐density polyethylene/(natural rubber)/(Kenaf powder) biocomposites

Biocomposites were prepared from a kenaf core powder and recycled high‐density polyethylene/(natural rubber) blend by using an internal mixer at 165^oC and 50 rpm. The effect of the filler content and the filler surface treatment was studied. Chemical modification of kenaf filler was performed with alkali pretreatment followed by treatment with silane. Scanning electron microscopy and infrared spectroscopy studies confirmed changes in the chemical compositions and structural characteristics induced through the modification. It was found that treated biocomposites offered higher tensile strength and tensile modulus, but lower elongation at break compared with untreated biocomposites. Lower water absorption and higher thermal stability of the resultant biocomposites were also obtained when treated fillers were used. J. VINYL ADDIT. TECHNOL., 20:218–224, 2014. © 2014 Society of Plastics Engineers     

Analysis of energy service systems in urban areas and their CO2 mitigations and economic impacts

Three kinds of energy service system were examined as alternative energy systems in urban areas. A comparison of these energy systems was performed by finding Pareto optimum solutions for a multi-objective model. The model had two objective functions: CO₂ emission and cost to consumer. Various energy pricings were provided in the model as variables.     

l-Ascorbic acid as an alternative fuel for direct oxidation fuel cells

l-Ascorbic acid (AA) was directly supplied to polymer electrolyte fuel cells (PEFCs) as an alternative fuel. Only dehydroascorbic acid (DHAA) was detected as a product released by the electrochemical oxidation of AA via a two-electron transfer process regardless of the anode catalyst used. The ionomer in the anode may inhibit the mass transfer of AA to the reaction sites by electrostatic repulsion. In addition, polymer resins without an ionic group such as poly(vinylidene fluoride) and poly(vinyl butyral) were also useful for reducing the contact resistance between Nafion membrane and carbon black used as an anode, although an ionomer like Nafion is needed for typical PEFCs. A reaction mechanism at the two-phase boundaries between AA and carbon black was proposed for the anode structure of DAAFCs, since lack of the proton conductivity was compensated by AA. There was too little crossover of AA through a Nafion membrane to cause a serious technical problem. The best performance (maximum power density of 16 mW cm⁻²) was attained with a Vulcan XC72 anode that included 5 wt.% Nafion at room temperature, which was about one-third of that for a DMFC with a PtRu anode.     

Study on the Effects of Flow in the Volute Casing on the Performance of a Sirocco Fan

The flow at the exit from the runner blade of a centrifugal fan with forward curved blades (a sirocco fan) sometimes separates and becomes unstable. We have conducted many researches on the impeller shape of a sirocco fan, proper inlet and exit blade angles were considered to obtain optimum performance. In this paper, the casing shape were decided by changing the circumferential angle, magnifying angle and the width, 21 sorts of casings were used. Performance tests, inner flow velocity and pressure distributions were measured as well. Computational fluid dynamic calculations were also made and compared with the experimental results. Finally, the most suitable casing shape for best performance is considered.     

Determination of preservative and antimicrobial compounds in fish from Manila Bay, Philippines using ultra high performance liquid chromatography tandem mass spectrometry, and assessment of human dietary exposure

Ultra high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination of four paraben preservatives (methyl, ethyl, propyl and butyl) and two antimicrobial agents (triclosan and triclocarban) belonging to personal care products (PCPs) in 20 species of fish from Manila Bay (Philippines) was performed. Detection of PCPs with greater frequency indicates the ubiquitous contamination of Manila Bay. Concentrations of total paraben were one order of magnitude higher than the antimicrobials in almost all fish, except in Stolephorus indicus and Leiognathus equulus. A positive correlation was observed between parabens concentration and fish length (r = 0.31-0.49; p<0.05 to <0.001) and fish weight (r = 0.28-0.49; p<0.05 to <0.001), but not for the antimicrobials. The estimated dietary exposure values of the four parabens in the Philippines through fish is four orders of magnitude lower than the acceptable daily intake (ADI) of 10mg/kg/day, but the values of antimicrobials are just half of the ADI of TCS. To our knowledge, this is the first report of PCPs contamination in fish from Philippines.     

Investigation of pesticide residues in foods distributed in Kitakyushu City

We investigated 160 kinds of pesticide residues in 715 samples of 116 kinds of foods distributed in Kitakyushu city. Sixty kinds of pesticides were detected in 55 kinds of foods (204 samples) in the range of 0.002-22 mg/kg. Five kinds of pesticides in 7 samples violated the residue standards and the indication of "unused". The detection ratios of unregulated pesticide in domestic and imported foods were 27.8 and 33.0%, respectively. Iprodione, dicofol, diethofencarb, procymidone and chlorfenapyr (for domestic food) and total bromine, benomyl, chlorpyrifos, dicofol, fenvalerate, cypermethrin and dimethoate (for imported food) showed relatively high detection ratios. Chinese cabbage, garland chrysanthemum, tomatoes and green teas (domestic) and broccoli, bananas, grapefruit, lemons, oranges, frozen edamame and frozen kidney beans (imported) showed high relative pesticide detection ratios. Residual pesticides were detected with relatively high frequency in imported fruits, imported frozen foods and imported processed foods.     

Laboratory and field measurements of dry deposition of sulfur dioxide onto Chinese loess surfaces

Laboratory and field measurements were conducted to examine dry deposition of SO2 onto Chinese loess surfaces using native soil sampled in the loess plateau, China. The field tests were employed in Beijing and Lanzhou, China, by directly measuring the dry deposition of SO2 on soil, which uses soil put on a collector as an SO2 passive sampling medium. In the laboratory, a high rate of uptake to SO2 deposition for Chinese soil surfaces due to the highly alkalinity was found. The uptake of SO2 deposition was dependent on the pH soil and relative humidity. Furthermore, we evaluated some factors that affect the measurement precision: response of SO2 uptake, repeatability, recovery factor, and variability associated with the weight and the surface coverage on the collectors. As a result, it was shown that the measurement precision was primarily related to the ratio of the SO2 deposition amount relative to the sulfur content of the original soil. This result was consistent with the field observations. The laboratory and field results indicated an excellent agreement on the SO2 uptake inherent in the results from the soil surfaces in different regions.     

Preparation of CdS-doped Glasses from Gels Containing Diethyldithiocarbamatocadmium

CdS-doped SiO₂ glasses were prepared via silica gels containing diethyldithiocarbamatocadmium Cd(S₂CN(C₂H₅)₂)₂. Heat treatment of the gels gave transparent yellow SiO₂glasses doped with hexagonal CdS crystals. In optical absorption and fluorescence spectra, the optical absorption edge and the emission peak clearly exhibited a blue shift, which was attributed to the quantum size effect of the carrier confinement, as the CdS content was decreased. In the fluorescence spectra of the CdS-doped silica glasses, the emission peak was observed only near 500 nm and not observed at longer wavelengths which were known to be present if there were sulfur vacancies.     

Building a CIM system for compound plant: Utilization of distributed processing system

The position of a production management system in a computer-integrated manufacturing (CIM) system is to serve as the nucleus of the plant CIM system that connects the plant production to other departments such as marketing, research and development, and distribution departments. A production management system that integrates the flow of goods with information in a plant, and thus manages production in it, was developed as the first step toward application of CIM to a powder plant. The method of building a distributed system is one way to build a CIM system. This method creates a system in the required function units, which are connected by a network to expand the system function. It offers advantages in extensibility, flexibility, and rapid implementation.