To meet the increasing demands of international telecommunications in Japan, 32-storied building (KDD Building) was constructed in Tokyo in 1974. In order to feed power to the telecommunication equipments, the constant voltage and constant frequency uninterruptible power plant of 4000 kVA which will meet the demand of power consumption required for the future increase of telecommunication equipments was decided to be installed in the basement. AC power generated in this power plant is fed to the telecommunication equipment floors by distribution trunk lines where the AC power is converted into AC or DC power required for each telecommunication equipment. This paper describes the design, configuration and reliability of the telecommunications power supply system (UPS).
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Abstract Potassium trans(N)-(C-methyl substituted ammoniatriacetato)(β-alaninato)cobaltate(III) have been prepared, where C-methyl substituted ammoniatriacetates are (S)-alaninate-N,N-diacetate and (R,S)- or (S,S)-alaninate-N-isopropionate-N-acetate. Some of the possible isomers concerning the arrangement of three feet of the tripod-like quadridentate ligand have been isolated and assigned structurally on the basis of the nuclear magnetic resonance spectra and isomerization experiments.
Dilute aluminium alloys and 5-nine aluminium were quenched in a vacuum, helium or hydrogen atmosphere, and the formation of the secondary defects was examined with an electron microscope. Helium and hydrogen atoms clearly affect the formation of voids and the promotive effect of helium is smaller than that of hydrogen. Using a set of rate equations, the promotive effect of both kind of atoms is discussed from the differences in their solubility, migration energy and the binding energy between a vacancy and a void containing a helium or hydrogen atom.
The highly stereoselective total synthesis of the macrolide antibiotic, bafilomycin A(1) (1), the first specific potent inhibitor of vacuolar H(+)-ATPase, has been achieved by a convergent route involving the synthesis and coupling of its 16-membered tetraenic lactone and beta-hydroxyl hemiacetal side-chain subunits. The C1-C17 16-membered lactone aldehyde 2 was synthesized through the coupling of the C5-C11 vinyl iodide 4 and the C12-C17 vinylstannane 5, followed by construction of the C1-C4 diene and macrolactonization. The aldol coupling of 2 and the C18-C25 ethyl ketone 3 followed by desilylation provided 1, which was identical with natural bafilomycin A(1). The key synthetic segments 3-5 were effectively synthesized from the readily available chiral materials, D-glucose, ethyl (S)-lactate, and methyl (S)-3-hydroxy-2-methylpropionate, respectively.
