A Capture‐and‐Release Catalytic Flow System

Supported transition‐metal catalysts offer the promise of catalyst reuse in order to make chemical transformations more environmentally friendly and less expensive; however, catalysts that are supported on insoluble scaffolds often exhibit significantly reduced selectivities and rates. A capture/release strategy that unites the benefits of heterogeneous and homogeneous catalysis would overcome these current shortcomings. Herein, we report on a novel capture‐and‐release flow system that takes advantage of a non‐covalent pyrene? single wall nanotube (SWNT) interaction. We demonstrate that a Pd complex containing one or two pyrene arms is captured and released from a SWNT column at different rates and can be utilized for the homogeneous catalysis of Suzuki and Heck reactions.     

Synthesis of oxovanadium complexes and their apoptosis-inducing activity in leukemia cells

Vanadium complexes with different ligands were synthesized and evaluated for antiproliferative activity on U937 cells. The alkyl chain length of the ligands affected the antiproliferative activity, and two complexes-3b and 4-exhibited strong activities with IC(50) values of 6.02 and 3.90 μM respectively. Annexin V staining and DNA ladder formation indicated that these complexes induced apoptosis in U937 cells.     

Magnetooptical Property of Sodium Borosilicate Gel-Glass Containing Bi-YIG Fine Particles

Composite materials which consist of ferro- or ferrimagnetic fine particles in a glass matrix are expected to have a large residual magnetization and coercive force because of their fine magnetic domain structure, and has potential for superior magneto-optical properties compared with single or polycrystalline materials. In this study, the sodium borosilicate (NBS) glass containing Bi-substituted yttrium iron garnet (Bi _x Y_3–x Fe₅O₁₂: BiYIG) fine particles, which show a superior magneto-optical effect, was prepared by the sol-gel method. BiYIG fine particles were stable in NBS gel-glass matrix during densification because the sintering temperature (580°C) of NBS gel was low enough to avoid pyrolysis of BiYIG and the reaction between BiYIG fine particles and the matrix. The Faraday rotation angle spectrum of the composite after deducting the contribution of the NBS glass matrix was intermediate between the reported ones of YIG and Bi_0.25YIG polycrystalline thin films. The change of the Faraday rotation angles of the composite with imposing magnetic field showed a hysteresis loop. It was in good agreement with that of the magnetization curve of the composite.     

A novel method of control using chaotic dynamics in systems having many degrees-of-freedom

Chaotic dynamics in systems having many degrees of freedom are investigated from the viewpoint of harnessing chaos and is applied to complex control problems to indicate that chaotic dynamics has potential capabilities for complex control functions by simple rule(s). An important idea is that chaotic dynamics generated in these systems give us autonomous complex pattern dynamics itinerating through intermediate state points between embedded designed attractors in high-dimensional state space. A key point is that, with the use of simple adaptive switching between a weakly chaotic regime and a strongly chaotic regime, complex problems can be solved. As an actual example, a two-dimensional maze, where it should be noted that the set context is one of typical ill-posed problems, is solved with the use of chaos in a recurrent neural network model. Our computer experiments show that the success rate over several hundreds trials is much better, at least, than that of a random number generator. Our functional simulations indicate that harnessing of chaos is one of essential ideas to approach mechanisms of brain functions. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Preparation of novel hydrophobic fluorine-substituted-alkyl sulfate ionic liquids and application as an efficient reaction medium for lipase-catalyzed reaction

Various types of differently fluorinated-alkyl sulfate ionic liquids have been prepared; the hydrophobicity was dependent on the content ratio of the fluorine on the alkyl sulfate anion and 2,2,3,3,4,4,5,5-octafluoropentyl sulfate salts showed hydrophobic properties. Melting point and viscosity were also dependent on the fluorine contents of the anionic part, while conductivity was determined by the cationic part and not influenced by the fluorine contents. Efficient lipase-catalyzed transesterification was demonstrated using hydrophobic 1-butyl-3-methylimidazolim 2,2,3,3,4,4,5,5-octafluoropentyl sulfate ([bmim][C5F8]) as solvent.     

Adding visualization functions of DAVIS to Jasp: Mixing two Java-based statistical systems

Summary  Jasp is an experimental general purpose Java-based statistical system which adopts several new computing technologies. It has a function-based and object-oriented language, an advanced user interface, flexible extensibility and a server/client architecture with distributed computing abilities. DAVIS is, on the other hand, a stand-alone Java-based system, and is designed for providing advanced data visualization functions with easy operations by a GUI. In this paper, it is made possible to use tools of DAVIS from within Jasp, in order that the new integrated system can handle not only data filtering and statistical analysis but also data visualization. We develop a mechanism for extending the server/client system of Jasp to realize an efficient collaboration with DAVIS in the client-side. It is shown that the mechanism is straightforward and simple.     

Selective determination of trace arsenic and antimony species in natural waters by gas chromatography with a photoionization detector

Traces amounts of arsenic and antimony in water samples were determined by gas chromatography with a photoionization detector after liquidnitrogen cold trapping of their hydrides. The sample solution was treated with sodium hydroborate (NaBH₄) under weak-acid conditions for arsenic(III) and antimony(III) determination, and under strong-acid conditions for arsenic(III+V) and antimony(III+V) determination. Large amounts of carbon dioxide (CO₂) and water vapor obscured determination of arsine and stibine. Better separation from interference could be achieved by removing CO₂ and water vapor in two tubes containing sodium hydroxide pellets and calcium chloride, respectively. The detection limits of this method were 1.8 ng dm^?3 for arsenic and 9.4 ng dm^?3 for antimony in the case of 100-cm³ sample volumes. Therefore, it is suitable for determination of trace arsenic and antimony in natural waters.