Structural analysis of NaOH-alcohol treated coals

Six vitrinite-concentrated coal samples were treated with NaOH-alcohol at 300 or 350 °C for 1 h. The products were nearly all soluble in pyridine except those from the oldest coal (52.4% of extraction yield). Structural indices of these pyridine extracts were calculated from ultimate analytical values, molecular weight and ¹H-n.m.r. data. The younger coals have tetralin-type nuclei and bituminous coal has 5–6 rings, about 2 of naphthene type. The younger coals were estimated to have more frequent ether linkages.     

Reaction mechanism for the hydrogenolysis of coal-derived preasphaltene

Preasphaltene, prepared in advance from hydrogenation of Akabira coal, was further hydrogenated at 385 °C with a hydrogen initial pressure of 9.8 MPa for various reaction times. According to the structural analysis and the variation of the inert oxygen content of the remaining preasphaltene and the benzenesoluble product, it is concluded that the conversion of preasphaltene to asphaltene plus oil is principally the reaction of the splitting of ether linkages which reduces the polymerization degree and the saturation of the aromatic rings with hydrogen which increases the solubility in benzene.     

Perpendicular magnetization structure of Co-Cr films

In a perpendicular recording system, a Co-Cr film as a medium is capable of storing very high density signals. Lorentz microscopy of 1000 kV TEM was used to observe the structure of recorded magnetizations in Co-Cr films having perpendicular anisotropy. A composite medium of a Co-Cr film with a soft magnetic back layer was shown by Lorentz microscopy to have a horseshoe magnetization structure. The stable antiparallel magnetization of transition in the Co-Cr layer determined the head-on magnetization structure of the soft magnetic back layer, which consists of a new straw-rope domain structure. The perpendicular magnetization structure of the Co-Cr film was found to consist of small domains magnetized through the film thickness which correspond to the columnar microstructure of the film. Since the intrinsic hysteresis loop of a Co-Cr film was shown to essentially have an ideal rectangular shape, it can be concluded that the Co-Cr layer of a composite film can be recorded by an ideal magnetizing process with negligible demagnetizing field at the transition.     

Coal hydrogenolysis in the presence of NaOH

High pressure hydrogenolysis of coal was carried out in the presence of sodium hydroxide at 350–500 °C and initial pressures of 3, 10 and 13 MPa for 15–60 min. Similar experiments were carried out under nitrogen. The yield of solid product decreased with increased reaction temperature because of the increased production of gases which are mainly hydrocarbons. Extraction of the solid products, formed under hydrogen, with pyridine and benzene shows higher yields than when nitrogen is used. This indicates that depolymerization and hydrogenation reactions were accelerated in the presence of sodium hydroxide under hydrogen.     

Reaction of coal with quinoline during extraction

Yubari coal vitrite was extracted with quinoline at 420° C for 0–4 h and the products were separated into several fractions. Quinoline solubles (QS) and insolubles (QI) increased with time and the total recovered weight became nearly 200% of the original weight of the coal. A large part of this weight increase was due to the contribution of the formation of biquinoline and to quinoline addition to coal. Depolymerization to smaller molecules and polymerization to QI took place simultaneously via the addition of quinoline and the production of biquinoline.     

Construction from a single parent of baker's yeast strains with high freeze tolerance and fermentative activity in both lean and sweet doughs

From a freeze-tolerant baker's yeast (Saccharomyces cerevisiae), 2,333 spore clones were obtained. To improve the leavening ability in lean dough of the parent strain, we selected 555 of the high-maltose-fermentative spore clones by using a method in which a soft agar solution containing maltose and bromocresol purple was overlaid on yeast colonies. By measuring the gassing power in the dough, we selected 66 spore clones with a good leavening ability in lean dough and a total of 694 hybrids were constructed by crossing them. Among these hybrids, we obtained 50 novel freeze-tolerant strains with good leavening ability in all lean, regular, and sweet doughs comparable to that of commercial baker's yeast. Hybrids with improved leavening ability or freeze tolerance compared with the parent yeast and commercial baker's yeasts were also obtained. These results suggest that hybridization between spore clones derived from a single parent strain is effective for improving the properties of baker's yeasts.     

Expression of peroxisome proliferator-activated receptor gamma (PPARgamma) in rat aortic smooth muscle cells

Creation of isopenicillin N from delta-(L-alpha-aminodipyl)-L-cysteinyl-D-valine (ACV) in the penicillin and cephalosporin biosynthetic pathway is catalysed by isopenicillin N synthase (IPNS), a non-heme iron-containing dioxygenase. A tripeptide R-X-S motif which consists of arginine-281 and serine-283 (Cephalosporium acremonium IPNS numbering) was found to be conserved in IPNS and other related proteins. These two amino acids mentioned were proposed to have a role in ACV substrate binding by the recent Aspergillus nidulans IPNS crystal structure. Using site-directed mutagenesis arginine-281 in C. acremonium IPNS (cIPNS) was earlier found to be essential for catalysis by our group. Similarly, serine-283 in cIPNS was also altered by site-directed mutagenesis to determine its role in cIPNS. No measurable activity was detected from the resultant mutant using enzyme bioassays. It is most likely that the eliminatin of the mutant's substrate-binding capability similar to that of arginine-281 lead to the abolishment of the catalytic reaction. This highlights the importance of the R-X-S motif in the functionality of cIPNS.     

Preparation of poly[dl-lactide-co-glycolide]-based microspheres containing protein by use of amphiphilic diblock copolymers of depsipeptide and lactide having ionic pendant groups as biodegradable surfactants by W/O/W emulsion method

To develop the preparative method for poly(dl-lactide-co-glycolide)-based microspheres containing proteins, we prepared microspheres from mixture of poly(dl-lactide-co-glycolide) and polydepsipeptide-block-poly(dl-lactide) having cationic or anionic pendant groups. Since the latter amphiphilic copolymers consisting of hydrophobic poly(dl-lactide) segment and hydrophilic polydepsipeptide segment with amino or carboxyl groups could be converted to cationic or anionic block copolymers, they could act as biodegradable surfactants on the preparation of poly(dl-lactide-co-glycolide)-based microspheres by water-in-oil-in-water emulsion method. The amphiphilic block copolymers were established to stabilize primary emulsions on the preparation of microspheres by scanning electron microscopy. We investigated the effects of the addition of the block copolymers on the entrapment efficiency of protein, the release behavior of protein from microspheres and the stability of protein.     

Nonuniform azimuth image shift observed in the Radarsat images of ships in motion

This paper describes, for the first time to the authors' knowledge, the phenomenon of nonuniform azimuth image shift of a rigid body observed in the Radarsat synthetic aperture radar (SAR) images of cruising ships. The effect is caused by the different slant-range velocities of coherent scatterers across the hull associated with the ship motions. The slant-range velocity is estimated from the SAR image of an identified ship, and it is compared with that computed from a numerical model using the ship's specification and meteorological data. The result indicates that the dominant contribution to the nonuniform image shift is the pitching motion of the ship. Further comparison is made with the wave orbital velocity, and the results are shown to be in good agreement. Comparisons are also made between the SAR-derived slant-range velocities of two unknown ships and wave orbital velocities, and reasonable agreement is obtained. One of the ships' images exhibits not only nonuniform shift but also image skew. The latter skewing effect may be caused by rolling of the ship.