Roasting effects on the distribution of tocopherols and phospholipids within each structural part and section of soybeans

To clarify the effects of microwave roasting on the distribution of tocopherols and FA of phospholipids within soybeans, whole soybeans (Glycine max) were treated by microwave and further evaluted as compared to a raw sample. Tocopherol homologs, measured using HPLC, and phospholipid profiles, quantified with GC, were determined in the seed coat, the embryonic axis, and selections of cotyledons separated from three cultivars. The tocopherols were predominantly detected in the axis, followed by the cotyledons, and then very little in the coat. As much as 25% of the individual tocopherols originally present in the coat were lost at 12 min of roasting, whereas <25% was lost in the cotyledons and the axis after 20 min of roasting. The greatest rate of phospholipid loss (P<0.05) was observed in PE, followed by PC and PI, and their changing patterns were more pronounced in the coat than in the cotyledons or the axis. Thus, tocopherol content and phospholipid profiles change with microwave roasting according to tissue.     

Docosahexaenoic acid production from crude glycerol by <Emphasis Type="Italic">Schizochytrium limacinum</Emphasis> SR21

In our search for a substitute energy source, microalgal biodiesel has presented itself as a potential candidate. However, the development of biodiesel results in the overproduction of crude glycerol, which can cause undesirable environmental issues. The environmental harm can be minimized by converting crude glycerol into value-added products. One solution involves using a microalga Schizochytrium limacinum SR21 to convert crude glycerol into docosahexaenoic acid (DHA). DHA is an essential fatty acid, necessary for developing brain functions in infants and maintaining healthy brain activity in adults. In our study, the highest DHA productivity of 233.73 mg/g biomass was obtained using 3 % crude glycerol in Medium 2 at 20 °C under mixo/heterotrophic cultivation.     

Development of new‐type outdoor termination using composite insulator with SF6 gas: Commercial use for 77‐kV transmission lines and development for 154‐kV XLPE cable

Recently, composite insulators have been increasingly employed mainly for economic reasons. We have developed a new type of outdoor termination using a composite insulator, which can be installed horizontally on a steel tower in order to reduce the construction cost. In this outdoor termination, SF₆ gas is filled in the composite insulator and a cold shrinkable premolded rubber unit is applied instead of the combined use of a rubber‐molded stress relief cone, epoxy resin insulator and spring unit. The application of the composite insulator, SF₆ gas and cold shrinkable premolded rubber unit reduces the total weight and makes it possible to install the termination horizontally on the tower. The new‐type outdoor termination for 77‐kV XLPE cable has already been applied in commercial use and enabled a reduction of the construction costs for power transmission lines. A 154‐kV new‐type outdoor termination has been developed and its initial electrical tests were successfully completed. This paper describes the design and performance of both 77‐kV and 154‐kV new‐type outdoor termination, and a follow‐up survey of the 77‐kV new termination in a commercial use. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(4): 18– 26, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20511     

Geometrical indications of adsorbed hydrogen atoms on graphite producing star and ellipsoidal like features in scanning tunneling microscopy images: Ab initio study

Recent scanning tunneling microscopy (STM) experiments display images with star and ellipsoidal like features resulting from unique geometrical arrangements of a few adsorbed hydrogen atoms on graphite. Based on first-principles STM simulations, we have found that the model with three hydrogen atoms, in which the hydrogen atoms are symmetrically placed on the graphene sheet in an equilateral triangle, encompassing a complete hexagon ring of carbon atoms, reproduces the experimentally observed starlike STM patterns. Additionally, we confirm that an ortho-hydrogen pair is the configuration corresponding to the ellipsoidal images. These calculations reveal that when the hydrogen pairs are in the same orientation, they are energetically more stable.     

Maximum capacity of distributed generators connected to a distribution system with a step voltage regulator,as determined with an electric power density model

In a distribution system containing a step voltage regulator (SVR), the maximum capacity of distributed generators (DGs) is calculated for DGs completely dispersed on a distribution line. The maximum capacity of the DGs is calculated under the constraint of an upper or lower voltage regulation value and an allowable current value by using voltage and current profiles expressed analytically in terms of our proposed power density model. As the voltage control method for the SVRs, we consider the conventional SVR, whose transformation ratio is fixed to 1 if it detects reverse power flow, and a reverse power flow SVR which operates appropriately even if it detects reverse power flow. Calculation of the maximum capacity of DGs with respect to the power factor of the DGs indicates which parameters, including the power factor of the DGs, the distribution of the DGs, and the load, influence the maximum DG capacity. Calculation of the maximum capacity of DGs versus the system length indicates that the constraints can be subdivided into two modes in the conventional SVR and four modes in the reverse power flow SVR. The maximum DG capacity in the system with a reverse power flow SVR is larger than that in a system with the conventional SVR. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 41–51, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20591     

Improved lower temperature fracture toughness of ultrahigh strength 4340 steel through modified heat treatment

A modified heat treatment has been suggested whereby lower temperature plane-strain fracture toughness (K _IC) of 4340 ultrahigh strength steel is dramatically improved in developed strength and Charpy impact energy levels. The modified heat-treated 4340 steel (MHT-4340 steel) consists of a mixed structure of martensite and about 25 vol pct lower bainite which appears in acicular form and partitions prior austenite grains. This is produced through isothermal transformation at 593 K for a short time followed by an oil quench (after austenitizing at 1133 K and subsequent interrupted quenching in a lead bath at 823 K). The mechanical properties obtained at room temperature (293 K) and 193 K have been compared with those achieved using various heat treatments. Significant conclusions are as follows: the MHT-4340 steel compared to the 1133 K directly oil-quenched 4340 steel increased theK _IC values by 15 to 20 MPa • m^1/2 at increased strength and Charpy impact energy levels regardless of the test temperature examined. At 193 K,K _IC values of the MHT-4340 steel were not less than those of the 1473 K directly oil-quenched 4340 steel, in whichK _IC values are significantly enhanced at markedly increased strength, ductility, and Charpy impact energy levels. The MHT-4340 steels compared to austempered 4340 steels at 593 K, which have excellent Charpy impact properties, showed superiorK _IC values at significant increased strength levels irrespective of test temperatures. The lower temperature improvement inK _IC can be attributed to not only the crack-arrest effect by acicular lower bainite but also to the stress-relief effect by the lower bainite just ahead of the current crack.     

Verification of the energy-saving effect of the district heating and cooling system—Simulation of an electric-driven heat pump system

A district heating and cooling system (DHC) is expected to be a promising energy-saving measure for high-density business areas in Japan. However, it has not been verified what advantages of the DHC are important for energy conservation. The clarification of this issue is supposed to contribute to improving the energy efficiency of the DHC.