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81.
Hitoshi Furuhata 《Differential Geometry and its Applications》2009,27(3):420-429
The condition for the curvature of a statistical manifold to admit a kind of standard hypersurface is given as a first step of the statistical submanifold theory. A complex version of the notion of statistical structures is also introduced. 相似文献
82.
A novel container complex in which a 1.4 nm gold cluster is confined within a hexaporphyrin cage was synthesized; the cage showed notable confinement capability for the cluster core, but allowed the interpenetration of small molecules into the interstitial space. 相似文献
83.
Noro S Kitaura R Kondo M Kitagawa S Ishii T Matsuzaka H Yamashita M 《Journal of the American Chemical Society》2002,124(11):2568-2583
A combination of framework-builder (Cu(II) ion and 4,4'-bipyridine (4,4'-bpy) ligand) and framework-regulator (AF(6) type anions; A = Si, Ge, and P) provides a series of novel porous coordination polymers. The highly porous coordination polymers ([Cu(AF(6))(4,4'-bpy)(2)].8H(2)O)(n)(A = Si (1a.8H(2)O), Ge (2a.8H(2)O)) afford robust 3-dimensional (3-D), microporous networks (3-D Regular Grid) by using AF(6)(2-) anions. The channel size of these complexes is ca. 8 x 8 A(2) along the c-axis and 6 x 2 A(2) along the a- or b-axes. When compounds 1a.8H(2)O or 2a.8H(2)O were immersed in water, a conversion of 3-D networks (1a.8H(2)O or 2a.8H(2)O) to interpenetrated networks ([Cu(4,4'-bpy)(2)(H(2)O)(2)].AF(6))(n)(A = Si (1b) and Ge (2b)) (2-D Interpenetration) took place. This 2-D interpenetrated network 1b shows unique dynamic anion-exchange properties, which accompany drastic structural conversions. When a PF(6)(-) monoanion instead of AF(6)(2)(-) dianions was used as the framework-regulator with another co-counteranion (coexistent anions), porous coordination polymers with various types of frameworks, ([Cu(2)(4,4'-bpy)(5)(H(2)O)(4)].anions.2H(2)O.4EtOH)(n)(anions = 4PF(6)(-) (3.2H(2)O.4EtOH), 2PF(6)(-) + 2ClO(4)(-) (4.2H(2)O.4EtOH)) (2-D Double-Layer), ([Cu(2)(PF(6))(NO(3))(4,4'-bpy)(4)].2PF(6).2H(2)O)(n)(5.2PF(6).2H(2)O) (3-D Undulated Grid), ([Cu(PF(6))(4,4'-bpy)(2)(MeCN)].PF(6).2MeCN)(n)(6.2MeCN) (2-D Grid), and ([Cu(4,4'-bpy)(2)(H(2)O)(2)].PF(6).BF(4))(n) (7) (2-D Grid), were obtained, where the three modes of PF(6)(-) anions are observed. 5.2PF(6).2H(2)O has rare PF(6)(-) bridges. The PF(6)(-) and NO(3)(-) monoanions alternately link to the Cu(II) centers in the undulated 2-D sheets of [Cu(4,4'-bpy)(2)](n)() to form a 3-D porous network. The free PF(6)(-) anions are included in the channels. 6.2MeCN affords both free and terminal-bridged PF(6)(-) anions. 3.2H(2)O.4EtOH, 4.2H(2)O.4EtOH, and 7 bear free PF(6)(-) anions. All of the anions in 3.2H(2)O.4EtOH and 4.2H(2)O.4EtOH are freely located in the channels constructed from a host network. Interestingly, these Cu(II) frameworks are rationally controlled by counteranions and selectively converted to other frameworks. 相似文献
84.
Uchiyama M Naka H Matsumoto Y Ohwada T 《Journal of the American Chemical Society》2004,126(34):10526-10527
A regio- and chemoselective direct method for generation of functionalized aromatic aluminum compounds through deprotonative directed ortho-alumination using triisobutyl(tetramethylpiperidino)aluminate (iBu3Al(TMP)Li), prepared by mixing of triisobutylaluminum (iBu3Al) and lithium tetramethylpiperidide (LTMP) in THF, has been developed. Deprotonative alumination of various functionalized benzenes with the use of iBu3Al(TMP)Li proved effective for the direct generation of various ortho-functionalized aluminum aromatic and heteroaromatic derivatives, particularly those with electrophilic functional groups such as cyano, amide, and halogen. Direct alumination, followed by electrophilic trapping (with I2), provided a convenient preparative method for 1,2- or 1,2,3-multisubstituted aromatic compounds. The functionalized aromatic aluminate intermediate also was found to undergo copper- and palladium-catalyzed C-C bond-forming reactions very efficiently and highly regio- and chemoselectively. 相似文献
85.
Detection of 210 kDa receptor protein for a leaf-movement factor by using novel photoaffinity probes
Tomohiko Fujii 《Tetrahedron》2005,61(33):7874-7893
Circadian rhythmic plant leaf-movement, called nyctinasty, is controlled by a time-course change in the internal concentration of the leaf-movement factor in the plant body. We revealed that specific binding proteins (210 and 180 kDa) for the leaf-movement factor, potassium lespedezate (1), are contained in the plasma membrane of the plant motor cell by using novel synthetic photoaffinity probes. These proteins are localized on the motor cell in the plant body, and would be potential receptors for the leaf-movement factor to control the leaf-movement. Our study is a rare successful result of the detection of membrane receptors by using a synthetic photoaffinity probe designed on a biologically active natural product. And these results also advance a guideline for probe design towards successful photoaffinity labeling. 相似文献
86.
Takashi Okubo Susumu Kitagawa Mitsuru Kondo Hiroyuki Matsuzaka Tomohiko Ishii 《Angewandte Chemie (International ed. in English)》1999,38(7):931-933
Anions PF 6 − and CF 3 SO 3 − are trapped by the new radical host [(Cu-dppe)3{hat-(CN)6}]2+, which was synthesized in a one-pot reaction from a copper(I ) source, hat-(CN)6, and dppe in acetone. The trapped salts have been characterized both in solution and in the solid state (see picture: A−: PF6−, CF3SO3−). hat-(CN)6=hexaazatriphenylene hexacarbonitrile; dppe=1,2-bis(diphenylphosphanyl)ethane. 相似文献
87.
Ryo Yoshida Hisao Ichijo Toshikatsu Hakuta Tomohiko Yamaguchi 《Macromolecular rapid communications》1995,16(4):305-310
Novel gel systems demonstrating rhythmically pulsatile mechanical motion similar to that of a heartbeat were developed. Self-oscillations of swelling and deswelling for the polymer hydrogels were realized by coupling pH and temperature sensitive hydrogels with a non-linear chemical reaction in the external solution media. The novel gel dynamics exhibiting cyclic and rhythmical oscillations may establish a new concept for functional materials that work under dynamic oscillating states. 相似文献
88.
We report on fundamental and intracavity frequency-doubled emission in a miniature Nd:YVO4 (3×3×1 mm) laser. A maximum slope efficiency of ηs=58.6%, with optical efficiency of η0=53.0% at 780 mW pump power was realized in a TEM00 output beam. To obtain the optimum pump-beam focusing conditions we applied a new formalism in which the pump-beam propagation in the active medium was described by its M2 factor. A good agreement between theoretical predictions and experimental results was observed. In second-harmonic regime, obtained by a KTP crystal, 230 mW green power that corresponds to 54% nonlinear conversion efficiency was reached. 相似文献
89.
A method that generalizes the notion of frontier orbital (FO) theory is introduced. The method is based on the projected reactive orbitals (PROs). Although PROs have been shown to describe local reactivity better than FOs in high-symmetry systems, the PRO method needs an arbitrary choice of a reference atomic orbital (AO), causing ambiguity of the method and poor applicability to low-symmetry molecules. To overcome these difficulties, we examined three different kinds of methods for uniquely determining the reference AO, one of which (Method 1) was reported by other authors (Kurita, Y.; Takayama, C. J. Phys. Chem. A 1997, 101, 5593-5595). We specifically applied the methods to the prediction of basicities of heteroaromatic amines. The study showed that the newly developed reactivity-index maximization method (Method 3) yields the most reasonable PRO. 相似文献
90.
Takahashi I Inomata T Funahashi Y Ozawa T Jitsukawa K Masuda H 《Chemical communications (Cambridge, England)》2005,(4):471-473
A new-class of promoter electrode bearing a molecular recognition ability has been constructed; the chirality and/or orientation of promoter on the Au electrode surface have affected the electron transfer rate of cytochrome c. 相似文献