Asymmetric synthesis of bicyclo[n.1.0]alkanes by the enantioselective 1,3-CH insertion reaction of chiral magnesium carbenoids

Treatment of enantiomerically pure 1-chlorovinyl p-tolyl sulfoxides, derived from cyclic ketones and (R)-chloromethyl p-tolyl sulfoxide, with the lithium enolate of tert-butyl carboxylates gave adducts in quantitative yields as single diastereomers. The adducts were treated with i-PrMgCl in toluene to afford optically active bicyclo[n.1.0]alkanes bearing a tert-butyl carboxylate moiety in up to 99% enantiomeric excess through the enantioselective 1,3-CH insertion reaction of the generated chiral magnesium carbenoids. This is the first example of the enantioselective 1,3-CH insertion reaction of magnesium carbenoid.     

Excitation and decay dynamics of 1s2s inner-shell double-vacancy states of neon atoms

The photo-excitation and Auger decay processes of inner-shell double vacancy states 1s2s2p^6（1,3^S）3s3p of neutral neon atoms have been studied theoretically. Multi-configuration Dirac-Fock （MCDF） calculations have been carried out, with electron correlation effects taken into consideration. The relaxation of core and excited orbitals and configuration interaction are found to be crucial to creating the double vacancy states by single photo-absorption. The predominant decay paths for the double vacancy states turn out to be of the LLM Auger decay to 1s 2s^22p^53s（3p）, KLL Auger decay to 1s^22s2p^43s3p, and KLM Auger decay to 1s^22p^63s（3p）. They lead to further Auger decay, creating the neon ions of multiple charge states. For both double and single vacancy states the spectator type of Auger process is dominated in all the Auger decay processes. Theoretical Anger electron spectra are presented for further investigations, experimental and theoretical.     

New sesquiterpenoids from the New Zealand liverwort Chiloscyphus subporosus

A new aromadendrane-type sesquiterpenoid, 4(15)-aromadendren-12,5alpha-olide and an aromadendrane-guaianolide dimer have been isolated from the New Zealand liverwort Chiloscyphus subporosus. Their structures were established by extensive NMR techniques and X-ray crystallographic analysis.     

Isovariant maps from free -manifolds to representation spheres

The isovariant version of Borsuk–Ulam type theorems has been studied by Wasserman and the first author. In this paper, first we consider the relation between the existence of C_n-isovariant maps from free C_n-manifolds to representation spheres and Borsuk–Ulam type inequalities for their dimensions. Our main result classifies the C_n-isovariant maps by C_n-isovariant homotopy types when a Borsuk–Ulam type inequality holds. For proving it, we use the multidegree of a C_n-equivariant map developed by the first author.     

iVDR business perspective

This paper describes a perspective for information versatile disk for removable usage (iVDR) business. iVDR is the best bridge media for high-resolution image because of high capacity and high reliability. The first iVDR product was delivered with PMR technology hard disk drives and a copyright protection function for high-definition TV programs. The business opportunity and the new business model are discussed.     

Catalytic activity and regeneration property of a Pd nanoparticle encapsulated in a hollow porous carbon sphere for aerobic alcohol oxidation

A core-shell composite consisting of a palladium (Pd) nanoparticle and a hollow carbon shell (Pd@hmC) was employed as a catalyst for aerobic oxidation of various alcohols. The core-shell structure was synthesized by consecutive coatings of Pd nanoparticles with siliceous and carbon layers followed by removal of the intermediate siliceous layer. Structural characterizations using TEM and N(2) adsorption-desorption measurements revealed that Pd@hmC thus-obtained was composed of a Pd nanoparticle core of 3-6 nm in diameter and a hollow carbon shell with well-developed mesopore (ca. 2.5 nm in diameter) and micropore (ca. 0.4-0.8 nm in diameter) systems. When compared to some Pd-supported carbons, Pd@hmC showed a high level of catalytic activity for oxidation of benzyl alcohol into benzaldehyde using atmospheric pressure of O(2) as an oxidant. The Pd@hmC composite also exhibited a high level of catalytic activity for aerobic oxidations of other primary benzylic and allylic alcohols into corresponding aldehydes. The presence of a well-developed pore system in the lateral carbon shell enabled efficient diffusion of both substrates and products to reach the central Pd nanoparticles, leading to such high catalytic activities. This core-shell structure also provided high thermal stability of Pd nanoparticles toward coalescence and/or aggregation due to the physical isolation of each Pd nanoparticle from neighboring particles by the carbon shell: this specific property of Pd@hmC resulted in possible regeneration of catalytic activity for these aerobic oxidations by a high-temperature heat treatment of the sample recovered after catalytic reactions.     

The unification of inflation and late-time acceleration in the frame of <Emphasis Type="Italic">k</Emphasis>-essence

By using the formulation of the reconstruction, we explicitly construct models of k-essence, which unify the inflation in the early universe and the late accelerating expansion of the present universe by a single scalar field. Due to the higher derivative terms, the solution describing the unification can be stable in the space of solutions, which makes the restriction for the initial condition relaxed. The higher derivative terms also eliminate tachyon. Therefore we can construct a model describing the time development, which cannot be realized by a usual inflaton or quintessence models of the canonical scalar field due to the instability or the existence of tachyon. We also propose a mechanism of the reheating by the quantum effects coming from the variation of the energy density of the scalar field.     

N-D-labeled ionic probes for mass spectrometry

An effective ¹⁵N- and deuterium (D)-labeled 2,6-bis(oxazolin-2-yl)pyridine (pybox)-La complex based probe ionization method that produces a distinct isotopic shift was developed. The distinct isotopic shift was detected by using the newly synthesized ¹⁵N-D-labeled pybox complexes. Moreover, O-[3-(tetramethylpybox)-propyl]-hydroxylamine (oxime-TMpybox) was prepared for attachment to the carbonyl group of the target molecule. Distinct isotopic shifts and multiple charged ions were detected for various compounds having amino, thiol, carboxyl, and carbonyl groups and fullerenes, using the TMpybox ionic probe series in cold-spray ionization mass spectrometry.     

Optical and Thermal Simulator for Laser-assisted Magnetic Recording

“Laser-assisted magnetic recording”, in which a recording media is heated by a laser beam while writing data, is attracting attention as a technology that enables a recording density of 1 Tb/in.². There exists another technology for media in which the recording layer is constructed with many small projections that enable high magnetic coercivity. This is called “patterned media”. For developing hard disk drives using these methods, we developed a simulator that analyzes the optical intensity distribution from the optical head for laser-assisted recording and the temperature profile on the patterned media. The simulator calculates the optical model using the finite-difference time-domain (FDTD) method. The thermal analysis of the three-dimensional model allows fast calculations using the alternating direction implicit (ADI) method. The heat source distribution data for thermal analysis is calculated in order to use the results of optical analysis. The optical and thermal analyses of the laser-assisted recording model were investigated with the simulator.     

Method development for the determination of 24S‐hydroxycholesterol in human plasma without derivatization by high‐performance liquid chromatography with tandem mass spectrometry in atmospheric pressure chemical ionization mode

We developed a highly sensitive and specific high‐performance liquid chromatography with tandem mass spectrometry method with an atmospheric pressure chemical ionization interface to determine 24S‐hydroxycholesterol, a major metabolite of cholesterol formed by cytochrome P450 family 46A1, in human plasma without any derivatization step. Phosphate buffered saline including 1% Tween 80 was used as the surrogate matrix for preparation of calibration curves and quality control samples. The saponification process to convert esterified 24S‐hydroxycholesterol to free sterols was optimized, followed by liquid–liquid extraction using hexane. Chromatographic separation of 24S‐hydroxycholesterol from other isobaric endogenous oxysterols was successfully achieved with gradient mobile phase comprised of 0.1% propionic acid and acetonitrile using L‐column2 ODS (2 μm, 2.1 mm id × 150 mm). This assay was capable of determining 24S‐hydroxycholesterol in human plasma (200 μL) ranging from 1 to 100 ng/mL with acceptable intra‐ and inter‐day precision and accuracy. The potential risk of in vitro formation of 24S‐hydroxycholesterol by oxidation from endogenous cholesterol in human plasma was found to be negligible. The stability of 24S‐hydroxycholesterol in relevant solvents and human plasma was confirmed. This method was successfully applied to quantify the plasma concentrations of 24S‐hydroxycholesterol in male and female volunteers.