Reduction of nitrate ion using hydrogen permeating Pd foil electrodes

The successive electrochemical reduction system using hydrogen-permeable Pd foil electrodes with Pd black catalyst was applied to reduction of nitrate ion. It was revealed that the second metals co-deposited to Pd black catalyst showed an excellent selectivity for decomposition of NO ₃ ⁻ to N₂, and was stable for at least 200 days. This system employing a compact and a simple electrolysis cell is expected to be an alternative or a supplement to conventional biological treatments for nitrate removal.     

Enantioselective aldol reaction of silyl ketene acetals promoted by a Lewis base-activated Lewis acid catalyst

The enantioselective aldol reaction of a silyl ketene acetal was promoted by chiral phosphine oxide-activated tetrachlorosilane to afford the corresponding adduct in high yield with moderate enantioselectivity.     

Applicability of silanol to sensitizing dye for dye-sensitized solar cell

Applicability of silanols to dye-sensitized solar cells was investigated for the first time with bis(4-azobenzene)silanediol as a model compound. The silanol dye showed high adsorption ability on the surface of TiO₂ electrode and effective electron transfer from the light-excited dye to the electrode was confirmed, exhibiting the effectiveness of the silanol dyes for the sensitizers.     

Influence of off-set energy on the electrical characteristics of Si resonant tunneling MOST (SRTMOST)

The effects of the off-set energy between the dielectric films which are formed at the both edges of the channel and the Si substrate on the electrical characteristics are examined for the Si resonant tunneling MOST (SRTMOST). The barrier height of the dielectric films has a great influence on the operation of the SRTMOST. The relationship between the transmission coefficient and the off-set energy of the double barrier/Si is calculated as well as the relationships between the gate-off currents, the transition time from the source to the drain and the off-set energy. It was found that the critical off-set energy of dielectric film/Si is approximately 1.0–1.5 eV.     

Synthesis of polycyclic nitrogen‐containing heterocyclic: One pot formation of 1,6‐naphthyridine ring system by reaction of amino‐cyano‐methylthio‐heterocycles with dialkyl acetyeledicarboxylates

Reaction of 3‐amino‐3‐methylthio‐2‐cyanoacrylonitrile (1) with excess dimethyl acetylenedi‐carboxylate(DMAD) in the presence of potassium carbonate in dimethyl sulfoxide gave a novel tricyclic heterocycle, hexamethyl lH‐1,4,7‐triazaphenalene‐2,3,5,6,8,9‐hexacarboxylate ( 5a ). When one equivalent of DMAD was used in this reaction, dimethyl 4‐amino‐3‐cyano‐2‐methylthiopyridine‐5,6‐dicarboxylate ( 3a ), a key intermediate of 5a , was obtained.     

Synthesis and [3+2] cycloaddition reaction of 3‐[(trimethylsilylmethylamino)(methylthio)‐methylene]heterocyclic compounds

3‐[(Trimethylsilylmethylamino)(methylthio)]methylene‐2‐coumaranone ( 4a ) and 1‐methyloxindole ( 4b ), readily prepared by reactions of the corresponding bis(methylthio)methylene heterocyclic compounds ( 2a, b ), with (trimethylsilylmethyl)amine (3), were found to be synthetic equivalents of heterocyclic alkylidene‐azomethine ylides. Reactions of 4a, b with reactive heterodipolarophiles such as aldehydes and ketones and reactive alkenes in the presence of cesium fluoride gave the 1,3‐dipolar cycloadducts, 3‐(2‐oxazoli‐dinylidene)‐oxindole and ‐coumaran‐2‐one derivatives ( 8a‐j, 9a‐h ), as well as pyrrolylidenecoumaran‐2‐one and oxindole derivatives ( 12‐15,17,18 ), via the 1,3‐elimination of (methylthio)trimethylsilane.     

Establishment of an analytical method for accurate purity evaluations of acylcarnitines by using quantitative 1H NMR spectroscopy

Accreditation and Quality Assurance - Recently, it has become possible to examine metabolism abnormalities by detecting increases in specific acylcarnitines in blood tests of newborn babies using...