Liquid sensing properties of melt processed polypropylene/poly(ε-caprolactone) blends containing multiwalled carbon nanotubes

The sensing properties of polypropylene (PP)/poly(ε-caprolactone) (PCL) blends containing multiwalled carbon nanotubes (MWNT) were studied in terms of their electrical resistance change in presence of liquids (solvents). The preparation of co-continuous blends based on the double percolation concept was done by melt mixing of electrically conductive PCL composites containing 3 wt.% MWNT and neat PP in ratios of 30:70, 40:60, and 50:50. The electrical resistance change of the PCL-MWNT composites and blends was monitored in a solvent immersion/drying cycle. Various solvents, such as n-hexane, ethanol, methanol, water, toluene, chloroform, and tetrahydrofuran were successfully detected, yielding different responses and reversibility of the resistance changes.PP and PCL were tested separately for solvent sorption using ethanol and n-hexane, both showing a low sorption of n-hexane. Ethanol sorption was large for PCL and almost absent for PP. The 50/50 blend composites with 3 wt.% MWNT in the PCL phase presented larger resistance changes for n-hexane, showing larger sensing ability for this solvent compared to PCL composites with 1 and 3 wt.% loadings. The opposite response was observed for immersion in ethanol where the PCL-MWNT composites showed larger changes than the blends. As the ratio of the conductive PCL phase over PP in the blend composition (i.e. the overall MWNT content) decreased, larger resistance changes were observed. The liquid sensing properties of compression-moulded discs and melt-drawn filaments were compared indicating higher responses for the discs.     

Stability of the physical properties of plasticized edible films from squid (Todarodes pacificus) mantle muscle during storage

Edible films from squid mantle muscle plasticized with different plasticizers were stored at 25 °C, 50% RH before the determination of physical properties. The results showed that tensile strength significantly increased (P < 0.05) upon the storage time, especially for the film plasticized with glucose, while there was no significant change (P ≥ 0.05) in elongation at break of all plasticized films. Water vapor permeability of glucose-plasticized film significantly decreased (P < 0.05) during storage, while there was only a slight change in those with glycerol, sorbitol, and fructose. Redness and yellowness of the films became significantly higher (P < 0.05) during storage, especially for the films plasticized with fructose and glucose. SDS-PAGE and protein solubility in SDS solution showed a possibility of protein aggregation throughout the storage. From these results, it is suggested that the changes in physical properties of the films were caused by the progress of Maillard reaction. PRACTICAL APPLICATION: In this study, squid mantle muscle was used as an edible film-forming material. By mixing with Na-citrate, squid mantle muscle possessed the ability to form transparent films with an excellent UV barrier property. Glycerol was found to be the most effective and stable plasticizer for the films. Edible films represent an option for the utilization of discarded squid during the fishing process.     

Antioxidative properties of aqueous and aroma extracts of squid miso prepared with Aspergillus oryzae-inoculated koji

To evaluate the antioxidative properties of a newly developed fermented paste (squid miso) prepared from squid mantle flesh with Aspergillus oryzae-inoculated koji, we used in vitro models, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, nitric oxide (NO) and carbon-centered radical-scavenging activity (RSA), reducing power ability (RPA), and linoleic acid oxidation. The antioxidant activity of volatile compounds, which were extracted from squid miso by dichloromethane, was confirmed based on the results obtained by the oxidation models consisting of carotene linoleate and hexanal. The RSA of the miso against several radicals, including DPPH, hydroxyl, nitric oxide and carbon-centered radicals measured by ESR spectrometry increased gradually through the fermentation period. On the other hand, the RPA increased rapidly in early stages of fermentation. Proteins were hydrolyzed to peptides and amino acids during fermentation. Certain peptides of low molecular mass significantly contributed to RSA. 4-Ethylguaiacol in the RSA active fraction, which was obtained by column chromatography, was the most potent antioxidative in the volatile extract. Analysis of phenolics in ethyl acetate fraction clearly suggested that 4-ethylguaiacol in the squid miso is possibly a bioconversion product of ferulic acid derived from koji. However, the aqueous extracts containing antioxidative peptides contributed more remarkably to radical scavenging than heterocyclic volatiles and phenolics.     

Superior catalytic behavior of trace Pt-doped Ni/Mg(Al)O in methane reforming under daily start-up and shut-down operation

Doping effects of Pt and Ru on Ni/Mg(Al)O catalysts were compared in daily start-up and shut-down operations of steam reforming of CH₄. Trace Pt-doped catalyst showed better behavior than trace Ru-doped catalyst; the former was self-activated but the latter was not, although both exhibited self-regenerative activity. Moreover, the former exhibited sustainable activity, although the latter was quickly passivated, in the autothermal reforming of CH₄. Formation of Pt–Ni alloy on the surface of fine Ni metal particles on the catalysts was suggested by EXAFS analyses. CH₄ was dissociatively activated to form hydrogen on Pt, assisted by adsorbed O or OH species, leading to the self-activation via Ni reduction by hydrogen spillover from Pt. The self-regeneration of the Pt–Ni/Mg(Al)O catalysts can be achieved by the continuous rebirth of active Ni metal species via reversible reduction–oxidation between Ni⁰ and Ni²⁺ in/on Mg(Ni,Al)O periclase assisted by the hydrogen spillover.     

Effect of extra N-terminal residues on the stability and folding of human lysozyme expressed in Pichia pastoris

A human lysozyme expression system by Pichia pastoris was constructedwith the expression vector of pPIC9, which contains the     

One stage operation for aneurysm of the diverticulum of the ductus arteriosus and coronary artery bypass grafting

The effect of ofloxacin (CAS 82419-36-1), dapsone (CAS 80-08-0), rifampicin (CAS 13282-46-1) and clofazimine (CAS 2030-63-9) on the generation of superoxide anions was studied in vitro. The drugs were incubated with a superoxide generating system (photochemical reaction between riboflavin and dianisidine). The change in optical density was measured. The optical density was increased with dapsone and ofloxacin and decreased in presence of clofazimine and rifampicin. This result indicates that ofloxacin and dapsone have an antioxidant property, whereas clofazimine and rifampicin behave as pro-oxidants.     

Thin film characteristics of fluorine-substituted monolayers prepared by chemical adsorption from solution

Monolayers containing a fluorine-substituted carbon chain were prepared by the chemical adsorption (CA) technique. Characteristics of the monolayers were evaluated by spectroscopy, copper decoration technique, current-voltage characteristics (current density and resistivity), measurement of the contact angle, and friction tests. By the copper decoration technique, the CA monolayer was more pinhole free and uniform than a Langmuir-Blodgett film. The characteristics (such as the leakage current density, resistivity, critical surface tension and coefficient of kinetic friction) of the fluorine-substituted monolayers depended markedly on the number of substituted fluorine atoms.     

Effect of meat washing on the development of impact odorants in fish miso prepared from spotted mackerel

BACKGROUND: Miso, a fermented soybean paste prepared using koji (rice malt inoculated with Aspergillus oryzae) has been commonly used as a traditional seasoning for several centuries in East Asian countries. A miso‐like fermented product was prepared using washed and unwashed meats of spotted mackerel (Scomber australasicus) with improved food functionality and aroma attributes. The evolution of aroma‐active volatiles was further evaluated during the early stages of maturation. RESULTS: The newly developed fermented product was rich in flavor. The product was found to contain 98 volatile compounds, including aldehydes, alcohols, esters, ketones, furans, sulfur‐ and nitrogen‐containing compounds, aromatics, and acids. Koji enzymes efficiently hydrolyzed protein and carbohydrate substrates in both the unwashed and washed fish meats. Significantly higher enzyme activities were observed when the unwashed meat was used as a raw material rather than when washed meat was used. The substrate specificity of koji enzymes plays an important role in the formation of volatile compounds. CONCLUSION: The results confirmed that meat washing can reduce the levels of certain aldehydes, ketones, and nitrogen‐containing compounds, and can thereby provide a pleasant aroma by reducing fishy odor in the finished product. Copyright © 2010 Society of Chemical Industry     

Semantic segmentation of trajectories with improved agent models for pedestrian behavior analysis

ABSTRACT

In this paper, we propose a method for semantic segmentation of pedestrian trajectories based on pedestrian behavior models, or agents. The agents model the dynamics of pedestrian movements in two-dimensional space using a linear dynamics model and common start and goal locations of trajectories. First, agent models are estimated from the trajectories obtained from image sequences. Our method is built on top of the Mixture model of Dynamic pedestrian Agents (MDA); however, the MDA's trajectory modeling and estimation are improved. Then, the trajectories are divided into semantically meaningful segments. The subsegments of a trajectory are modeled by applying a hidden Markov model using the estimated agent models. Experimental results with a real trajectory dataset show the effectiveness of the proposed method as compared to the well-known classical Ramer-Douglas-Peucker algorithm and also to the original MDA model.     

3D spectroscopic measurement of argon and metal vapour in MIG welding

Spectroscopic measurements for gas-metal arc (GMA) phenomena have been recently performed. The studies have reported that the metal vapour behaviour greatly affects the arc properties. However, they can be applied only to axially symmetric phenomena because of the assumption used for the measurement. GMA welding are normally performed with a travel speed, and most of the phenomena become axially asymmetric. This study constructed the simultaneous and multidirectional measurement system by 12 CCD cameras which can capture such axially asymmetric GMA phenomena. We measured the metal inert gas welding process with use of two types of narrowband interference filters for Ar I and Fe I during the one measurement, and observed axially asymmetrical intensity distributions in the globular and the spray transfer mode. We found that the globular transfer mode that is seemingly chaotic distribution can be regarded as the distribution where the deviation of Ar I is larger than Fe I from the axially symmetric double-ring distribution that consists of Ar I and Fe I.