Two-Dimensional Near-Field Optical Spectroscopy in Magnetic Fields up to 4 T

We have developed a magnetic-field-type scanning near-field optical microscopy (SNOM) system, which enables us to obtain two-dimensional near-field images under magnetic fields up to 4 T. We have performed two-dimensional near-field scanning optical spectroscopy on (Cd,Mn) Te self-assembled quantum dots with this system.     

Dynamic three-point bending tester using inertial mass and optical interferometer

A method for generating and measuring varying force by means of levitating a rigid object is discussed in this paper. The inertial force is accurately measured using an optical interferometer and an electric frequency counter. The performance of the three-point bending tester based on the proposed idea is investigated. The 12 sets of three-point bending tests have been conducted against aluminum bars. The combined standard uncertainty in measuring the instantaneous value of the reaction force, with the sampling interval of approximately 1–2 ms, is approximately 0.11 N. This corresponds to approximately 3×10⁻³ (0.3%) of the maximum inertial force in the experiments.     

On detonation behavior of mixed fuels

An experimental study of detonation was carried out for mixed fuels (, and ). The results obtained demonstrate that detonation velocities of mixed fuels agree very well with normal C-J velocity and that detonation limits were not extended by the addition of a small amount of . As for mixed fuel, detonation velocities and detonation limits as a function of the equivalence ratio of the whole mixture of mixed fuel coincided with those of single fuel. However, the detonation induction time of a mixture of with a lower sensitivity to detonation decreased considerably with the addition of a small amount of . In addition, the influence of mixed fuels on the quasi-detonation and the fast deflagration in the process of DDT was investigated, showing interesting and complicated features in mixed fuel. Received 20 December 1994 / Accepted 20 November 1995     

Hydroalkylation of Styrenes with Benzylamines by Potassium Hydride

A method for the synthesis of 1,3-diarylpropylamines through hydroalkylation of styrenes with benzylamines by potassium hydride has been developed. The protocol is initiated by solvothermal treatment of benzylamines with KH at 100 °C to generate deprotonated anionic species, which undergo selective C-alkylation with arylalkenes at 0 °C to ambient temperature to afford 1,3-diarylpropylamines as the major product.     

Ligand accelerated indium(III)-catalyzed asymmetric alkynylation of aldehydes with 2-methyl-3-butyn-2-ol as an ethyne equivalent donor

Indium(III)-catalyzed asymmetric alkynylation of aryl, heteroaryl, alkyl and alkenyl aldehydes with 2-methyl-3-butyn-2-ol as an ethyne equivalent donor was realized, and products were obtained in moderate to good yields (up to 97%) and high enantioselectivities (up to 99% ee) using 2-10 mol% of catalyst.     

A practical synthesis of (-)-kainic acid

A highly practical stereoselective total synthesis of (-)-kainic acid is described. This synthesis features the stereoselective alkylation of an iodolactone intermediate that was efficiently prepared from (+)-carvone and introduction of carboxylic acid by hydrolysis of a nitrile accompanied by epimerizaion. This synthetic route enabled us to obtain 14.6 g of (-)-kainic acid.     

New imidazopyridopyrimidine:naphthyridine base-pairing motif, ImN(N):NaO(O), consisting of a DAAD:ADDA hydrogen bonding pattern, markedly stabilize DNA duplexes

The new imidazopyridopyrimidine:naphthyridine base-pairing motifs, ImO(O):NaN(N) and ImN(N):NaO(O), were designed. Among the base pairs examined, DNA duplexes containing ImN(N):NaO(O) pair(s) consisting of a DAAD:ADDA hydrogen bonding pattern (D = donor, A = acceptor) were markedly stabilized thermally and thermodynamically.     

Determination of the absolute configuration of the male aggregation pheromone, 2-methyl-6-(4′-methylenebicyclo[3.1.0]hexyl)hept-2-en-1-ol, of the stink bug Erysarcoris lewisi (Distant) as 2Z,6R,1′S,5′S by its synthesis

Lipase-catalyzed asymmetric acetylation of a mixture of (6R,1′S,4′S,5′R)- and (6R,1′R,4′R,5′S)-7′-norsesquisabinen-4′-ol (3) afforded a separable mixture of the recovered former and the acetate of the latter. The recovered alcohol was oxidized to (6R,1′S,5′R)-sesquisabina ketone (2), whose absolute configuration could be assigned by its CD comparison with (1R,5S)-sabina ketone (4). Conversion of (6R,1′S,5′R)-sesquisabina ketone (2) to the bioactive pheromone revealed the stereostructure of the male aggregation pheromone of the stink bug Erysarcoris lewisi (Distant) to be (2Z,6R,1′S,5′S)-2-methyl-6-(4′-methylenebicyclo[3.1.0]hexyl)hept-2-en-1-ol (sesquisabinen-1-ol, 1).     

Anaerobic oxidation of isobutane: Catalytic properties of MgV2O6 and Mg2V2O7 prepared by the molten method

The catalytic activity of MV₂O₆ and M₂V₂O₇ type oxides prepared by the molten method (MM) for anaerobic oxidation of isobutane was studied in order to construct a system for the selective oxidation of isobutene using a thin layer reactor. Isobutene, CO and CO₂ were formed by every catalyst tested. The activities for isobutene formation were CuV₂O₆ > ZnV₂O₆, NiV₂O₆, CoV₂O₆ > MgV₂O₆ > MnV₂O₆  CaV₂O₆. Isobutene was a major product over M₂V₂O₇ (MM). Co₂V₂O₇ showed the highest activity and high isobutene selectivity exceeded 90%, demonstrating that Co₂V₂O₇ is a suitable oxide for a thin layer reactor for anaerobic oxidation of isobutane. Partial substitution of Mg by Cu in Mg₂V₂O₇ (MM) improved the activity. It is shown by the oxidation at low O₂ concentration as 2–3% that two types of oxidations occurred simultaneously: isobutene formation by the lattice oxygen ions diffused from the bulk, and CO and CO₂ formation by the oxygen species derived from molecular oxygen in the gas phase.