Structural analysis of Ti-Fe thin films prepared by pulsed laser deposition

Titanium iron oxide (Ti-Fe-O) thin films have been successfully deposited by pulsed laser deposition (PLD). Experiments were carried out by using some targets. One was a Ti-50 at.% Fe-sintered target, while the others were Ti and Fe plates with various surface area ratio [S_R=S_Fe/(S_Fe+S_Ti)] from 30 to 70%. The thin films were analyzed by X-ray diffractometry, Rutherford backscattering spectroscopy (RBS) and transmission electron microscopy (TEM). From XRD analysis, the main phase in the thin films deposited at S_R=30 and 50% was β-Ti (Fe). By increasing S_R to 70%, the main phase of the thin film changed to TiFe. By phase diagram, composition of TiFe must be between Ti-47.5-50.3 at.% Fe at a temperature of 1085 °C. However, the composition of the thin film deposited at S_R=70% was found to be Ti_0.15Fe_0.62O_0.23. Thus, the composition of Fe in the thin film was much greater than the solubility limit. This fact suggests two possibilities. One is that the thin films, which we have deposited, were in a metastable state. The other is that metal oxides of amorphous state could be contained in the thin film.     

Experimental study of several types of ground heat exchanger using a steel pile foundation

An experimental study of several types of ground heat exchangers (GHEs) installed in a steel pile foundation, including double-tube, U-tube, and multi-tube GHEs, was carried out at Saga University. Water flows through the heat exchangers and exchanges heat to or from the ground. The performance of GHEs was investigated under actual operation in the cooling mode with flow rates of 2, 4, and 8 l/min. Temperatures of the ground and GHE tube wall were measured to find the temperature distributions according to the depth of the ground and depth of the GHE tube wall. The temperatures of the inlet and outlet of circulated water were also measured to calculate the heat exchange rate. The double-tube had the highest heat exchange rate, followed by the multi-tube and U-tube GHEs. For example, the average heat exchange rate of GHEs over 24 h of continuous operation with a flow rate of 4 l/min was 49.6 W/m for the double-tube, 34.8 W/m for the multi-tube, and 30.4 W/m for the U-tube. An increasing flow rate increased the heat exchange rate of the GHEs. The heat exchange rates increased significantly for flow rate increases from 2 to 4 l/min, but only slightly changed from 4 to 8 l/min.     

Isolation of hesperidin from peels of thinned Citrus unshiu fruits by microwave-assisted extraction

Simultaneous extraction by microwave-irradiation and crystallisation were performed in the same pot of solvent of 70% (v/v) aqueous ethanol for isolation of hesperidin from thinned immature fruit peels of Citrus unshiu as refining of Citrus waste biomass. The hesperidin content in immature fruits peels was about 3.2-fold higher than that of mature fruit. After microwave-assisted extraction (MAE), the yield of hesperidin reached 58.6 mg/g, which was comparable to the amount obtained after extraction using DMSO:methanol (1:1, v/v) as a solvent for 30 min at room temperature. Heating temperature and time for isolation of hesperidin crystallites were optimised as 140 °C and 8 min by using response surface methodology. Under this optimal condition, 86.8% (47.7 mg/g) of total hesperidin was isolable by MAE and low-temperature storage (5 °C, 24 h).     

Production of Lacto-N-biose I Using Crude Extracts of Bifidobacterial Cells

Lacto-N-biose I (LNB) is supposed to represent the bifidus factor in human milk oligosaccharides, and can be practically produced from sucrose and GlcNAc using four bifidobacterial enzymes, 1,3-β-galactosyl-N-acetylhexosamine phosphorylase, sucrose phosphorylase, UDP-glucose-hexose 1-phosphate uridylyltransferase, and UDP-glucose 4-epimerase, recombinantly produced by Escherichia coli. Here the production of LNB by the same enzymatic method without using genetically modified enzymes to consider the use of LNB for a food ingredient was reported. All four enzymes were produced as the intracellular enzymes of Bifidobacterium strains. The mixture of the crude extracts contained all four enzymes, with other enzymes interfering with the LNB production, namely, phosphoglucomutase, fructose 6-phosphate phosphoketolase, and glycogen phosphorylase. The first two interfering enzymes were selectively inactivated by heat treatment at 47 °C for 1 h in the presence of pancreatin, and glycogen phosphorylase was disabled by hydrolyzing its possible acceptor molecules using glucoamylase. Finally, 91 % of GlcNAc was converted into LNB in the 100-mL reaction mixture containing 300 mM GlcNAc.     

Monodisperse microspheres of copolymers of glycidyl methacrylate and its derivatives as materials for biomedical application

Monodisperse microspheres of copolymers of glycidyl methacrylate were prepared by dispersion polymerization in organic media. The microsphere diameter could be adjusted in the range from 0$md$5 μm to 5μm by changing the monomer concentration, the type of dispersion medium and the content of the comonomers. Terpolymers of glycidyl methacrylate, 2-hydroxyethyl methacrylate and tri(ethylene glycol) dimethacrylate were analysed by thermal decomposition gas chromatography and the compositions of the polymers agreed well with those of the monomer mixtures. The epoxide of the polymer microspheres was hydrolysed to α,β-diol with dilute sulphuric acid without side reactions except the slight formation of sulphate. It was confirmed by the ¹³CFT-NMR spectrum that the main structure of the hydrolysate was that of poly(glyceryl methacrylate). In the reaction of the epoxide with ammonia, the predominant production of tertiary amine was presumed by the relationship between the conversion of the epoxide and the nitrogen content of the reaction product. The amination of the epoxide with secondary amines resulted in the quantitative formation of the corresponding tertiary amines.     

Ethanol-tolerant Saccharomyces cerevisiae strains isolated under selective conditions by over-expression of a proofreading-deficient DNA polymerase δ

Ethanol damages the cell membrane and functional proteins, gradually reducing cell viability, and leading to cell death during fermentation which impairs effective bioethanol production by budding yeast Saccharomyces cerevisiae. To obtain more suitable strains for bioethanol production and to gain a better understanding of ethanol tolerance, ethanol-tolerant mutants were isolated using the novel mutagenesis technique based on the disparity theory of evolution. According to this theory evolution can be accelerated by affecting the lagging-strand synthesis in which DNA polymerase δ is involved. Expression of the pol3-01 gene, a proofreading-deficient of DNA polymerase δ, in S. cerevisiae W303-1A grown under conditions of increasing ethanol concentration resulted in three ethanol-tolerant mutants (YFY1, YFY2 and YFY3), which could grow in medium containing 13% ethanol. Ethanol productivity also increased in YFY strains compared to the wild-type strain in medium containing 25% glucose. Cell morphology of YFY strain cells was normal even in the presence of 8% ethanol, whereas W303-1A cells were expanded by a big vacuole. Furthermore, two of these mutants were also resistant to high-temperature, Calcofluor white and NaCl. Expression levels of TPS1 and TSL1, which are responsible for trehalose biosynthesis, were higher in YFY strains relative to W303-1A, resulting in high levels of intracellular trehalose in YFY strains. This contributed to the multiple-stress tolerance that makes YFY strains suitable for the production of bioethanol.     

Exploiting DLP Illumination Dithering for Reconstruction and Photography of High-Speed Scenes

In this work, we recover fast moving scenes by exploiting the high-speed illumination “dithering” of cheap and easily available digital light processing (DLP) projectors. We first show how to reverse-engineer the temporal dithering for off-the-shelf projectors, using a high-speed camera. DLP dithering can produce temporal patterns commonly used in active vision techniques. Since the dithering occurs at a very high frame-rate, such illumination-based methods can be “speed up” for fast scenes. We demonstrate this with three applications, each of which only requires a single slide to be displayed by the DLP projector. The quality of the result is determined by the camera frame-rate available to the user. Pairing a high-speed camera and a DLP projector, we demonstrate structured light reconstruction at 100 Hz. With the same camera and three or more DLP projectors, we show photometric stereo and demultiplexing applications at 300 Hz. Finally, with a real-time (60 Hz) or still camera, we show that DLP illumination acts as a very fast flash, allowing strobe photography of high-speed scenes. We discuss, in depth, some characteristics of the temporal dithering with a case study of a particular projector. Finally, we describe limitations, trade-offs and other issues relating to this work.     

Synthesis and characterization of deoxycholyl 2-deoxyglucuronide: A water-soluble affinity labeling reagent

Acyl glucuronides, which are biosynthesized by the action of glucuronosyltransferases to material for detoxification, are water-soluble and chemically active; they produce irreversible protein adducts via both the transacylation mechanism and the imine mechanism. The acyl group at the C-1 position migrates from the anomeric carbon to the C-2 position of the glucuronic acid moiety, producing the aldehyde group at the C-1 position, where the protein easily condenses through a Schiff's base, in the open-chain aldose form. The elimination of the hydroxyl group at the C-2 position therefore may prevent a protein-bound adduct via the imine mechanism. In this paper, we describe the synthesis and characterization of an acyl 2-deoxyglucuronide of deoxycholic acid as a model compound to investigate its possible utility as a water-soluble affinity labeling reagent for lipophilic carboxylic acids. The solubility of deoxycholyl 2-deoxyglucuronide in an aqueous solution was sufficient under physiological conditions, and the desired material reacted with model peptides to produce covalently bound adducts only via the transacylation mechanism.