Chemical composition and structural identification of eutectic carbide in 1 pct Mn ductile iron

Manganese, which may be used in ductile cast iron as a potent hardenability promoter, segregates in the intercellular region. This segregation becomes more severe as a consequence of poor inoculation, low cooling rate, or increasing of nominal Mn content in the alloy. In severely Mn-segregated regions, Mn eutectic carbide may be formed, which has a deteriorating effect on the mechanical properties of casting. In this study, a 1 Pct Mn ductile iron was used to investigate the chemical composition and crystal structure of the Mn eutectic carbide by electron microscopy (scanning and transmission), X-ray, and an electron probe microanalyzer (EPMA). Transmission electron microscope (TEM) and X-ray studies show that the crystal structure of carbide is orthorhombic with lattice parameters ofa = 14.825,b = 11.415, andc = 8.880 (Å). The concentrations of Mn, Si, and Cr in carbide, analyzed by scanning electron microscope-energy-dispersive X-ray spectrometer (SEM-EDX) and transmission electron microscope-energy-dispersive X-ray spectrometer (TEM-EDX), were 5.0 to 7.0, 0.5 to 2.8 and 1.5 to 2.2 (wt Pct), respectively. The ratio of Fe plus other metal atoms to C was calculated from EPMA experiments to be 2.5-2.9. It was shown that by diminishing Mn segregation, precipitated eutectic carbide can be reduced. It is expected that this can be achieved by reducing nominal content of Mn or by increasing nodule count.     

Sugar consumption and ethanol fermentation by transporter-overexpressed xylose-metabolizing Saccharomyces cerevisiae harboring a xyloseisomerase pathway

Four kinds of transporters, HXT1 and HXY7 from Saccharomyces cerevisiae, and GXF1 and GXS1 from Candida intermedia, were overexpressed in xylose-metabolizing S. cerevisiae harboring a xyloseisomerase-based pathway. Overexpression of transporter enhanced sugar consumption and ethanol production, and GXF1 was efficient for ethanol fermentation from both glucose and xylose.     

Effects of Austenizing Temperature on Reprecipitation of BN

Most of BN was precipitated around the spherical MnS and formed the compound of MnS and BN during the isothermal treatment at 850 °C after austenizing at 950 — 1050 °C. Most of MnS was transformed into polygon when austenized at 1150 °C or above, which could not be the nuclei of BN anymore. During the insulation process at 850 °C, MnS kept the state of monomer. The compound of MnS and BN at earlier time was of fine polycrystalline in spherality and BN was formed as a plate-like monocrystal on a certain part of the polycrystalline when its dimension reached 0. 6 μm.     

A 12-ps-resolution digital variable-delay macro cell on GaAs 100K-gates gate array using a meshed air bridge structure

A digital variable-delay macro cell (DVDM) on a GaAs 100 K-gates gate array has been developed for measurement instruments and for elimination of clock skew on printed circuit boards. Three new technologies for high resolution are introduced into the DVDM: (1) a meshed air bridge structure bringing 29% reduction of propagation delay, (2) a rising edge selector circuit creating 33% decrement of standard deviation σ on delay, and (3) a delay circuit with a discharge control path for a high resolution of 12 ps. The DVDM produces 24.4 ns span and 12 ps resolution, about one-quarter that of a conventional DVDM. Linearity error is less than ±27 ps. Power dissipation of the DVDM is 250 mW/cell, about one-third of the value for a conventional Si bipolar junction transistor analog delay circuit     

Photodarkening effect in sputtered films of sulphur- and/or selenium-based chalcogenide glasses

We studied the photodarkening effect in films of Ge₁₀As₄₀Se₂₅S₂₅, Ge₂₅Se₇₅ and Ge_22.5As₁₀Se_67.5. The transmissivities of the films were measured as a function of the exposure time and the contrast indices γ were obtained. These results were compared with values calculated from the rate equations, and the photodarkening process was analysed.     

Efficient drug delivery to alveolar macrophages and lung epithelial lining fluid following pulmonary administration of liposomal ciprofloxacin in rats with pneumonia and estimation of its antibacterial effects

The efficacy of pulmonary administration of liposomal ciprofloxacin (CPFX) in pneumonia was evaluated. In brief, the pharmacokinetics following pulmonary administration of liposomal CPFX (particle size, 1,000 nm; dose, 200 microg/kg) were examined in rats with lipopolysaccharide-induced pneumonia as an experimental pneumonia model. Furthermore, the antibacterial effects of liposomal CPFX against the pneumonic causative organisms were estimated by pharmacokinetic/pharmacodynamic (PK/PD) analysis. The time-courses of the concentration of CPFX in alveolar macrophages (AMs) and lung epithelial lining fluid (ELF) following pulmonary administration of liposomal CPFX to rats with pneumonia were markedly higher than that following the administration of free CPFX (200 microg/kg). The time course of the concentrations of CPFX in plasma following pulmonary administration of liposomal CPFX was markedly lower than that in AMs and ELF. These results indicate that pulmonary administration of liposomal CPFX was more effective in delivering CPFX to AMs and ELF compared with free CPFX, and it avoids distribution of CPFX to the blood. According to PK/PD analysis, the liposomal CPFX exhibited potent antibacterial effects against the causative organisms of pneumonia. This study indicates that pulmonary administration of CPFX could be an effective technique for the treatment of pneumonia.     

Improving ambient wind environments of a cross-flow wind turbine near a structure by using an Inlet Guide Structure and a Flow Deflector

Introductions Denmark was the first country to use the wind for electricity generation practically. The windmill was developed by the Dane Poul La Cour who incorporates the aerodynamic design principle into the blades of the windmill in 1890[1,2]. After that, many countries developed the windmill for the electricity generation. But the use of cheaper fossil fuel took the lead in the electricity generation. Many wind electric generations were far from success in business. In 1970’s, The O…