Bacterial contamination in an egg-breaking factory and its control

From January to November, 2003, bacterial contamination was surveyed in a small egg-breaking factory that produced non pasteurized liquid egg. Test egg samples were taken at various stages of the egg processing operation. Salmonella Enteritidis was isolated from liquid egg yolk and liquid egg white on October, but was not found in any other samples (50 liquid egg samples, 21 containers and 94 attached production facilities and gloves). The data suggest that the contamination rate (3.8%) is lower than those reported previously. Levels of bacterial standard plate counts, gram-positive bacterial counts and gram-negative bacterial counts were in the ranges of 2 to 5 log CFU/g, 2 to 3 log CFU/g, 2 to 5 log CFU/g, respectively. Liquid egg containers returned from customers was contaminated with bacteria at the level of 8 log CFU per container. However, washing and application of a sanitizer containing sodium hypochlorite reduced the bacterial counts.     

Dramatic effect of dispersed carbon nanotubes on the mechanical and electroconductive properties of polymers derived from ionic liquids

Free-radical polymerization of an imidazolium ion-based ionic liquid bearing a methacrylate group, gelling with single-walled carbon nanotubes (SWNTs), allows fabrication of a mechanically reinforced, electroconductive soft material (bucky plastic). A film sample of this material displays an excellent conductivity of 1 S cm(-1) and a 120-fold enhancement of the Young's modulus at a 7 wt % content of SWNTs. The conductivity is temperature-dependent in the range 5-300 K, suggesting that the conductive process involves carrier hopping. Scanning electron and atomic force micrographs of a bucky plastic film display the presence of crosslinked networks consisting of finely dispersed SWNTs. Such nanotube networks, developed in the polymer matrix, likely suppress slipping of entrapped polymer molecules via a strong interfacial interaction and also facilitate intertubular carrier transport. Although a bucky plastic derived from a vinylimidazolium ion-based ionic liquid monomer shows a comparable conductivity to that of the methacrylate version, the film is brittle irrespective of the presence or absence of SWNTs.     

Absolute quantitation of quercetin and the glycosides in natural food additives by quantitative NMR

We are developing a simple absolute quantitation method for organic compounds, by means of quantitative nuclear magnetic resonance (qNMR), with traceability to the International System of Units (SI units). The qNMR method was applied to the absolute quantitation of rutin, isoquercitrin and quercetin in natural food additives, rutin (extract), enzymatically decomposed rutin extract and quercetin, and those compounds as commercial reagents. In this study, 1,4-bis-(trimethylsilyl)benzene-d(4) (1,4-BTMSB-d(4)) whose purity was precisely evaluated on the basis of metrology, was newly used as a qNMR reference material, to be added to the sample solution as an internal standard. The contents of quercetin and quercetin glycosides were calculated from the ratio of the signal intensities of each aromatic proton at the 2' position of the three compounds (these are observed at different chemical shifts) to the eighteen protons of the six methyl groups on 1,4-BTMSB-d(4) used as a qNMR reference material. Rapid and simple qNMR method with only one step process was carried by using 1,4-BTMSB-d(4). It was demonstrated that the purities of rutin, isoquercitrin and quercetin can be separately determined by qNMR without the need for a separation process or reference materials for all the target compounds.     

Consistency, frequency, and lexicality effects in naming Japanese Kanji.

Japanese Kanji characters have various degrees of consistency of character-sound correspondences in multicharacter words. A word was classified as consistent, inconsistent typical, or inconsistent atypical with reference to the most typical pronunciations for constituent characters among words sharing the same characters. A nonword was classified as consistent, inconsistent biased, or inconsistent ambiguous according to the degree of pronunciation typicality of its constituent characters in real words. A word-naming experiment yielded a significant Frequency?×?Consistency interaction, and a nonword-naming experiment yielded significant consistency effects. In addition, both word frequency and lexicality exerted strong effects on efficiency of naming Kanji character strings. These results demonstrate the influence of Kanji print-sound correspondences both at subword and whole-word levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of main particle diameter on improving particle flowability for compressed packing fraction in a smaller particle admixing system

Particle flowability can be improved by admixing particles smaller than the original particles (main particles). However, the mechanisms by which this technique improves flowability are not yet fully understood. In this study, we examined compressed packing in a particle bed, which is affected by particle flowability. To estimate the mechanism of improvement, we investigated the effects of the main particle diameter on the improvement of compressed packing fractions experimentally.The main particles were 397 and 1460 nm in diameter and the admixed particles were 8, 21, 62, and 104 nm in diameter. The main and admixed particles were mixed in various mass ratios, and the compressed packing fractions of the mixtures were measured. SEM images were used to analyze the coverage diameter and the surface coverage ratio of the admixed particles on the main particles. The main particle packing fraction was improved as the diameter ratio (=main particles/admixed particles) increased. This was explained by a linked rigid-3-bodies model with leverage. Furthermore, the actual surface coverage ratio at which the most improved packing fraction was obtained decreased with increasing main particle diameter. This was explained by the difference in the curvature of the main particle surface.     

Neural Networks for Chemical Engineering Unit Operations

Application of artificial neural networks in simulation of chemical engineering unit operations are studied. On the basis of the present work it is suggested that the raw data describing the phenomenon should be processed so that the relationships of the input variables are studied and if relationships are found, such as dimensionless numbers, these relationships are set as inputs in the neural network. Further, if the phenomenon can be described by a simplified mathematical expression, the value calculated by such simplified solution is set as one of the inputs. The method is demonstrated by three examples, namely, by turbulent fluid flow in a tube, breakthrough curve of adsorption, and by suspension crystallization. In all cases the method presented in this work results in a more accurate simulation and in easier training of the neural network.     

Analysis of the constituents in jojoba wax used as a food additive by LC/MS/MS

Jojoba wax is a natural gum base used as a food additive in Japan, and is obtained from jojoba oil with a characteristically high melting point. Although the constituents of jojoba oil have been reported, the quality of jojoba wax used as a food additive has not yet been clarified. In order to evaluate its quality as a food additive and to obtain basic information useful for setting official standards, we investigated the constituents and their concentrations in jojoba wax. LC/MS analysis of the jojoba wax showed six peaks with [M+H]+ ions in the range from m/z 533.6 to 673.7 at intervals of m/z 28. After isolation of the components of the four main peaks by preparative LC/MS, the fatty acid and long chain alcohol moieties of the wax esters were analyzed by methanolysis and hydrolysis, followed by GC/MS. The results indicated that the main constituents in jojoba wax were various kinds of wax esters, namely eicosenyl octadecenoate (C20:1-C18:1) (1), eicosenyl eicosenoate (C20:1-C20:1) (II), docosenyl eicosenoate (C22:1-C20:1) (III), eicosenyl docosenoate (C20:1-C22:1) (IV) and tetracosenyl eiosenoate (C24:1-C20:1) (V). To confirm and quantify the wax esters in jojoba wax directly, LC/MS/MS analysis was performed. The product ions corresponding to the fatty acid moieties of the wax esters were observed, and by using the product ions derived from the protonated molecular ions of wax esters the fatty acid moieties were identified by MRM analysis. The concentrations of the wax esters I, II and III, in jojoba wax were 5.5, 21.4 and 37.8%, respectively. In summary, we clarified the main constituents of jojoba wax and quantified the molecular species of the wax esters without hydrolysis by monitoring their product ions, using a LC/MS/MS system.     

Circular dichroism of poly(β-benzyl-l-aspartate) films in the α, β and ω conformations

The conformations of poly(β-benzyl l-aspartate) (PBLA) in film were studied by means of circular dichroism (c.d.). Films of PBLA show c.d. which is related to the benzyl chromophores of this polypeptide. The magnitude and sign of the c.d. of the benzyl chromophores depend on the conformation i.e. α-helix, ω-helix or β-form. The aromatic c.d. of the left-handed α-helix or the left-handed ω-helix is negative in sign, and that of the β-form is positive in sign. The absolute magnitude of the c.d. of PBLA is much larger in the ω-helical conformation than in the α-helical or the β-conformations. In the left-handed α-helical PBLA (α-PBLA), the positive dichroism band of the $\text{n?π1}$ peptide electronic transition is observed at about 226 nm. When the α-PBLA is converted to the left-handed ω-helical PBLA (ω-PBLA), the band at 226 nm shifts to 224 nm, and its magnitude becomes much smaller. In the β-form PBLA (β-PBLA), this band is negative in sign and observed at 223 nm. The absolute magnitude of the c.d. relative to this electronic transition follows the order: β-form < ω-helix < α-helix.     

In-situ observation of structural change in MWCNTs under high-pressure H2 gas atmosphere

Multi-walled carbon nanotubes having a tube-opened framework (o-MWCNTs) have been pressurized in an atmosphere of hydrogen up to 2.5 GPa and at room temperature using a diamond-anvil cell (DAC). Compression up to 0.57 GPa was accompanied by expansion of the honeycom-lattice structure of graphene sheets in spite of decreasing interlayer distance. A deviation in the in-plane C–C distance was obtained to be 3.8 × 10^− 4 nm at 0.57 GPa. The expansion in the honeycom-lattice structure suggests generation of charge-transfer interaction between graphite and hydrogen. This is one of the proofs that hydrogen is intercalated in the interlayer space of o-MWCNTs.     

Effect of paddle rotational speed on particle mixing behavior in electrophotographic system by using parallel discrete element method

The objective of this paper is to investigate the effect of paddle rotational speed on the mixing behavior in an agitation process of an electrophotographic system by using parallel DEM. The mixing behaviors of beads with different sizes and densities were measured at various paddle rotational speeds by using a high-speed video camera, and were compared with the simulation results. A good agreement in the mixing behavior was obtained and the changes in particle velocity during the mixing were comparable. The simulation for mixing behavior of larger carrier particles suggested that the radial particle mixing was much faster than the axial one. The faster radial mixing is attributed to the fact that there are two radial flows in the system; the one is over the shaft, the other is between the paddle and shaft. The extent of mixing depended on the number of paddle rotations when the rotational speed is larger than 100 rpm, while the mixing under 50 rpm is completed at a smaller number of rotations.