Mesoporous Magnetic Materials Based on Rare Earth Oxides

A novel family of mesoporous oxides of rare earth metals (Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were synthesized with specific surface areas of 253-348 m(2) g(-1) and pore diameters of 2.5-3.0 nm (see Scheme). The mesoporous solids and their surfactant mesophase precursors are paramagnetic and exhibit a magnetic anomaly due to the mesostructured atomic arrangement.     

Synthesis, structure, and cooperative proton-electron transfer reaction of Bis(5,6-diethylpyrazinedithiolato)metal complexes (M = Ni, Pd, Pt)

New proton and electron donors, M(II)(HL)(2) (M = Ni, Pd, Pt; L = 5,6-diethylpyradzinedithiolate), as well as a proton and electron acceptor, Pt(IV)(L)(2), were prepared and characterized. The pH-dependent cyclic voltammetry of the M(II)(HL)(2) complexes revealed a favorable Gibbs free energy (K(com) > 1) for the proton and electron transfer reactions from M(II)(HL)(2) to M(IV)(L)(2); i.e., the equilibrium for the following reaction lies to the right: M(II)(HL)(2) + M(IV)(L)(2) <==>2M(III)(HL)(L).     

Efficient thermal conversion of polyyne-type conjugated polymers to nano-structured porous carbon materials

Summary Some aromatic based conjugated polymers having carbon-carbon triple bonds moiety were synthesized and carbonized. The polymers were efficiently carbonized by heating up to 900°C under an argon atmosphere, affording porous carbons in high yields. The polymer characteristics were appropriate to form nano-structured carbons in the pyrolytic carbonization process. The carbon materials were consisted of 2-4 nm sized graphitic crystallites and had slit-shaped micropores with ca. 0.7 nm pore width. Structural defects in the pre-carbon materials caused generation of mesopores with ca. 4 nm pore width after carbonization.     

Protective effects of an antioxidant derived from serine and vitamin B6 on skin photoaging in hairless mice

The generation of reactive oxygen species (ROS) by ultraviolet radiation (UVR) accelerates skin aging, which is known as photoaging. Because cutaneous iron catalyzes ROS generation, sequestering iron by chelating agents is thought to be an effective approach toward preventing photoaging. Previously, N-(4-pyridoxylmethylene)-l-serine (PYSer) was designed as an antioxidant to suppress iron-catalyzed ROS generation by its iron-sequestering activity. In this study, PYSer showed protective effects against skin damage in hairless mice irradiated with ultraviolet B (UV-B). Topical application of PYSer to the skin significantly delayed and/or decreased the visible wrinkle formation induced by chronic UV-B irradiation. A histological study indicated that UV-B-induced epidermal hypertrophy and lymphocytic infiltration were suppressed by PYSer. Moreover, PYSer showed suppressive activity against the UV-B-induced increase in glycosaminoglycans (GAG). These results indicate that PYSer is a promising antioxidant for the prevention of chronic skin photoaging by its iron-sequestering activity.     

CO laser-microwave double-resonance spectroscopy of H2CO with intense Stark field: Precise measurement of dipole moment in the ground and ν2 vibrational states

Stark-shifted microwave transitions in the ground and ν₂ vibrational states of H₂CO were observed by means of CO laser-microwave double-resonance with intense electric field. High sensitivity and precision were attained by the use of multireflection absorption cell, optical-flat Stark plates, and microwave frequency stabilization. Dipole moments determined from some individual rotational transitions in the ground and ν₂ vibrational states are, in Debye, with uncertainties in parentheses,

     

147.

Zinc-mediated allylation and alkylation of aminals in the presence of TMSCl and diisopropylamine     

Hatano B  Nagahashi K  Kijima T 《The Journal of organic chemistry》2008,73(22):9188-9191

An alkylation of aminals with organozinc reagents derived from allyl bromide, benzyl bromide, alpha-bromoacetate, and alpha-bromonitrile proceeded efficiently in the presence of TMSCl and diisopropylamine. This reaction system was applied to the synthesis of an antispasmodic: butaverine.     

148.

Network Polysilanes: Synthesis,Electrical Conductivity,Charge‐Transfer Interaction,and Photoconductivity     

Takanobu Kobayashi  Hirokazu Shimura  Shin Mitani  Saeko Mashimo  Aiko Amano  Toshihisa Takano  Minoru Abe  Hamao Watanabe  Masashi Kijima  Hideki Shirakawa  Hiroyuki Yamaguchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2000,112(17):3240-3244

     

149.

Mesostructured Rare Earth,Aluminum and Gallium Oxides Templated by Surfactant Assemblies     

Mitsunori Yada  Tsuyoshi Kijima 《ChemInform》2002,33(48):222-222

     

150.

Stochastic orders and their applications in financial optimization     

Masaaki Kijima  Masamitsu Ohnishi 《Mathematical Methods of Operations Research》1999,50(2):351-372

Stochastic orders and inequalities are very useful tools in various areas of economics and finance. The purpose of this paper is to describe main results obtained so far by using the idea of stochastic orders in financial optimization. Especially, the emphasis is placed on the demand and shift effect problems in portfolio selection. Some other examples, which are not related directly to optimization problems, are also given to demonstrate the wide spectrum of application areas of stochastic orders in finance.     

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Transition		G.S.		$\text{ν}{}_2$		δμ
110 ← 111		2.3315 (1)		2.3472 (1)		0.0157 (1)
211 ← 212		2.3313 (1)		2.3471 (1)		0.0158 (1)
312 ← 313		2.3313 (1)		2.3470 (1)		0.0157 (1)
826 ← 827		2.3311 (1)		2.3466 (1)		0.0155 (1)
927 ← 928		—		2.3466 (1)		—

Zinc-mediated allylation and alkylation of aminals in the presence of TMSCl and diisopropylamine

An alkylation of aminals with organozinc reagents derived from allyl bromide, benzyl bromide, alpha-bromoacetate, and alpha-bromonitrile proceeded efficiently in the presence of TMSCl and diisopropylamine. This reaction system was applied to the synthesis of an antispasmodic: butaverine.     

Stochastic orders and their applications in financial optimization

Stochastic orders and inequalities are very useful tools in various areas of economics and finance. The purpose of this paper is to describe main results obtained so far by using the idea of stochastic orders in financial optimization. Especially, the emphasis is placed on the demand and shift effect problems in portfolio selection. Some other examples, which are not related directly to optimization problems, are also given to demonstrate the wide spectrum of application areas of stochastic orders in finance.