Effects of injection molding conditions on the electrical properties of polycarbonate/carbon nanotube nanocomposites

Polycarbonate/Carbon nanotube (PC/CNT) nanocomposites containing various CNT contents (0–5 wt%) were prepared by injection molding. The effects of CNT contents, injection speed (V) and injection temperature (T) on the electrical resistivity of the PC/CNT nanocomposites were investigated. It was found that the tensile strength of nanocomposites was enhanced slightly with increased CNT contents, and the tensile modulus was 29% greater after the 5 wt% CNT addition, but the brittle tendency became stronger. Aside from tensile properties, the electrical resistivity of the nanocomposites dropped 12 orders of magnitude after the 5 wt% CNT addition. Also, there was a tendency that the electrical resistivity was lower in the case of higher injection temperature and lower injection speed. Scanning electron microscope (SEM) images and the distribution of surface layer electrical resistivity, clearly showed a notable influence by surface layer microstructures on the electrical resistivity, and the injection conditions affected both the value of the maximum electrical resistivity and the position where it occurred. This study offers an alternative green and simple molding process to prepare conductive PC nanocomposites and to achieve the industrialization of PC/CNT nanocomposite products which can be used in electromagnetic shielding and anti‐static fields. POLYM. COMPOS., 37:3245–3255, 2016. © 2015 Society of Plastics Engineers     

Photodegradation of perfluorooctane sulfonate by UV irradiation in water and alkaline 2-propanol

Perfluorooctane sulfonate (PFOS) is the environmentally concerned compound because of its persistence and bioaccumulative properties. Since photodegradation of PFOS is not yet experimentally confirmed, photodegradation study of PFOS in water and alkaline 2-propanol solution was conducted. Aqueous and alkaline 2-propanol solution of PFOS (40 microM) was irradiated with a low-pressure mercury lamp (254 nm, 32 W) by internal irradiation for 10 d, and then PFOS, fluoride and sulfate ions, and the other degradation products were analyzed. Photodegradation of PFOS was confirmed in both media. PFOS was degraded by 8% after 1 day and by 68% after 10 days irradiation compared to the initial concentration in water. In alkaline 2-propanol, 76 and 92% of PFOS was degraded after 1 and 10 days irradiation, respectively. Photodegradation of PFOS in alkaline 2-propanol was much faster and effective than in water, as the photodegradation rate constants were 0.93 days(-1) in alkaline 2-propanol and 0.13 days(-1) in water, respectively. Formation of fluoride and sulfate was also confirmed by ion chromatography and X-ray diffraction analysis. From observation of the degradation products, two major degradation pathways of PFOS were considered: via C8HF17 and C8F17OH, respectively, resulting in short-chain fluorinated compounds such as C7HF15 and C7F15OH by stepwise removal of CF2. Formation of short-chain fluorocarbons such as CF4, C2F6, and C3F8 were also confirmed. This is the first study to confirm photodegradation of PFOS in water and alkaline 2-propanol.     

Isolation, amino acid sequence and biological activities of novel long-chain polyamine-associated peptide toxins from the sponge Axinyssa aculeata

A novel family of functionalized peptide toxins, aculeines (ACUs), was isolated from the marine sponge Axinyssa aculeate. ACUs are polypeptides with N-terminal residues that are modified by the addition of long-chain polyamines (LCPA). Aculeines were present in the sponge extract as a complex mixture with differing polyamine chain lengths and peptide structures. ACU-A and B, which were purified in this study, share a common polypeptide chain but differ in their N-terminal residue modifications. The amino acid sequence of the polypeptide portion of ACU-A and B was deduced from 3' and 5' RACE, and supported by Edman degradation and mass spectral analysis of peptide fragments. ACU induced convulsions upon intracerebroventricular (i.c.v.) injection in mice, and disrupted neuronal membrane integrity in electrophysiological assays. ACU also lysed erythrocytes with a potency that differed between animal species. Here we describe the isolation, amino acid sequence, and biological activity of this new group of cytotoxic sponge peptides.     

Boiling refrigerant‐type panel cooler (refrigerant circulation and cooling performance)

We have developed a new compact boiling refrigerant type panel cooler. It is a closed two‐phase loop thermosiphon constructed with heat exchanger cores for an automobile air conditioning system. We confirmed higher performance of the natural refrigerant circulation type and tried to optimize the size of the refrigerant path in the boiling core by observing the internal refrigerant flow and successfully achieved much higher cooling performance. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(2): 94–105, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20003     

A preliminary analysis of item‐selection behavior of Japanese female university students examining a 2D virtual fashion web site

E‐commerce is spreading into various fields in our daily lives as a result of the growth of interactive Internet communication technologies. Two‐dimensional computer graphics (2D CG) image presentations, which are simple and inexpensive, can be displayed directly on apparel e‐commerce sites. This study uses sequential pattern mining to analyze the item‐selection behavior of Japanese female university students examining a 2D virtual fashion Web site. It is found that most users did not initially examine their favorite category items; instead, they examined the commonly viewed items first, and then examined various other fashion items before making their final selection. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Oral Glucosylceramide Reduces 2,4-Dinitrofluorobenzene Induced Inflammatory Response in Mice by Reducing TNF-Alpha Levels and Leukocyte Infiltration

Sphingolipids are constituents of cellular membranes and play important roles as second messengers mediating cell functions. As significant components in foods, sphingolipids have been proven to be critical for human health. Moreover, diverse metabolic intermediates of sphingolipids are known to play key roles both in proinflammatory and in anti-inflammatory effects. However, the effect of dietary sphingolipids on inflammation is a complicated field that needs to be further assessed. Our study evaluated the effects of orally administered maize glucosylceramide (GluCer), one of the most conventional dietary sphingolipids, on inflammation using the 2,4-dinitro-1-fluorobenzene-treated BALB/c murine model. Oral administration of GluCer inhibited ear swelling and leukocyte infiltration to the inflammatory site, suggesting that dietary GluCer has anti-inflammatory properties. ELISA analyses revealed that oral administration of GluCer for 6 days had not modified the Th1/Th2 balance, but significantly down-regulated the activation of TNF-α at the inflammatory site. Based on these results, the down-regulation of TNF-α by dietary GluCer may suppress vascular permeability and reduce the migration of inflammatory cells. Our findings increase understanding of the actions of dietary sphingolipids on the balance of the immune response.     

Solar space heating and cooling with bi-heat source heat pump and hot water supply system

This paper describes a specific heat pump system that can solve the problem of low heating capacity at a low ambient temperature—one of the largest problems in the air-source heat pump system.

In order to decrease the collector area required, the heat pump system is operated by the air-source during the daytime, but at night or at a very low ambient temperature it can be operated with hot water which has been produced by the collector in the daytime. The effect of the solar energy on the air-source heat pump system has many advantages in the moderate winter climate of Japan. The hot water supply system includes an auxiliary electric heater.

The experiment has been carried out with a prefabricated test house, which has been constructed in Nara with double glazed windows and high thermal insulation. The results of this experiment are that solar energy enhances the total electric energy savings, increases the heating capacity at low ambient temperature, and eliminates the need for reverse cycle defrosting operation, etc.     

Efficient reconfiguration of distribution networks using extended pruning‐grafting operators

Network reconfiguration is a complicated, combinatorial, constrained optimization problem with many candidate switching options as well as structural and operational constraints. Introduction of evolutionary algorithms (EAs) to distribution network operation has opened many new opportunities. However, many applications of these methods suffer from high computational burden. In addition, conventional crossover/mutation operators cannot generally produce radial configurations. Performance of EAs is significantly affected by modeling of the problem and the employed operators. This paper employs a branch‐based modeling of a distribution network and proposes two new EA operators that are an extension and redefinition of the preserve ancestor operator (PAO) and change ancestor operator (CAO). They are fast, exclusively produce radial configurations, and remove PAO/CAO operators' limitation. Hence, they can be utilized for a more efficient application of EAs to the network reconfiguration problem. Performance of the new operators is compared to the original PAO/CAO operators, two sets of operators in a binary representation (conventional crossover/mutation operators and an enhanced version of them), and a set of operators in an integer representation (conventional crossover and directed mutation operators). Simulations show the efficiency of the proposed method in terms of convergence speed, response time, and the quality of results. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Effect of Existence of Exogenous Protein on Physicochemical Properties of Heat- and Transglutaminase-induced Bovine Collagen-peptide Gel

ABSTRACT: The combined influence of preheat treatment, mixing with various proteins, and the addition of microbial transglutaminase (MTGase) on the physicochemical properties of bovine collagen-peptide (BCP) gel was investigated. The preheat treatment and the mixing with various proteins contributed to the enhancement of the gel strength and polymerization of BCP. The gel made with 0.1% MTGase showed the highest breaking strength. The melting point of the preheated BCP gel was higher than that of the unheated one ( P < 0.05). The gel made with a combination of preheated BCP-casein or preheated BCP-soybean protein showed a higher melting point than that made with preheated BCP alone ( P < 0.05). The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) pattern of the mixture of preheated BCP with casein or soybean protein showed that the protein bands with relatively low molecular weights disappeared and the bands with relatively high molecular weights increased. Observation by a scanning electron microscope revealed that the preheated BCP gel prepared with MTGase had a well-defined cross-linked network and showed some clumps of aggregated proteins. These results show that preheating, mixing with other proteins and MTGase treatment, are effective ways to make BCP a fine biopolymer.