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81.
Noboro Nishii Katsuya Hashimoto Rokuro Okawara 《Journal of organometallic chemistry》1973,55(1):133-137
Several adducts of monoorganoantimony tetrachlorides, RSbCl4L (R = CH3, C6H5, p-CH3C6H4; L = HMPT, PyO, 4-CH3PyO, DMSO), were prepared. In the solid state all of these adducts are stable at room temperature. They are monomeric in solution, and the existence of hexacoordinate antimony is indicated. CH3SbCl4L (L = PyO, 4-CH3PyO) exists in two isomeric forms in solution and decomposes above 70° into CH3Cl and SbCl3L. CH3SbCl4(HMPT) decomposes in a similar manner even at room temperature. 相似文献
82.
Wang Z Zhang B Otsuka T Inoue K Kobayashi H Kurmoo M 《Dalton transactions (Cambridge, England : 2003)》2004,(15):2209-2216
We present the synthesis, characterization by IR, TGA, single crystal X-ray structure and magnetic properties of a novel series of NaCl-type frameworks of [AmineH(+)][Mn(HCOO)(3)(-)], templated by alkylammonium. The anionic NaCl-framework of [Mn(HCOO)(3)(-)] is counter-balanced by the alkylammonium cations located in the cavities of the framework to which they are hydrogen-bonded. The divalent manganese ions have octahedral geometry and are bridged by the formate in an anti-anti mode of coordination. All the compounds exhibit long-range antiferromagnetism below 9 K with a slight non-collinear arrangement of the moments. The canting, likely due to second-order spin-orbit coupling, is via a Dzyaloshinski-Moriya antisymmetric exchange mechanism. A spin-flop is observed in each case at fairly low fields. An orthorhombic to monoclinic transformation was observed for the protonated cyclotrimethyleneamine that is accompanied by localization of the cations into two positions below 240 K from the rapid dynamic flipping of the ring observed at room temperature. 相似文献
83.
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Inside Back Cover: Electrical Network of Single‐Crystalline Metal Oxide Nanoclusters Wired by π‐Molecules (Angew. Chem. Int. Ed. 42/2014)
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86.
Morikawa T Pan Y Ninomiya K Imura K Yuan D Yoshikawa M Hayakawa T Muraoka O 《Chemical & pharmaceutical bulletin》2010,58(10):1403-1407
Three iridoid glycosides, kankanosides L, M, and N, and two acyclic monoterpene glycosides, kankanosides O and P, were isolated from fresh stems of Cistanche tubulosa (Orobanchaceae) together with eight iridoid glycosides, five acyclic monoterpene glycosides, three phenylpropanoid glycosides, and four lignan glycosides. Their structures were elucidated on the basis of chemical and physicochemical evidence. 相似文献
87.
Hidetoshi Nakano Katsuya Oguri Yasuaki Okano Tadashi Nishikawa 《Applied Physics A: Materials Science & Processing》2010,101(3):523-531
We investigated spatiotemporal evolution of expanding ablation plume of aluminum created by a 100-fs, 1014–1015-W/cm2 laser pulse. For diagnosing dynamic behavior of ablation plume, we employed the spatiotemporally resolved X-ray absorption
spectroscopy (XAS) system that consists of a femtosecond-laser-plasma soft X-ray source and a Kirkpatrick–Baez (K–B) microscope.
We successfully assigned the ejected particles by analyzing structure of absorption spectra near the L
II,III absorption edge of Al, and we clarified the spatial distribution of Al+ ions, Al atoms, and liquid droplets of Al in the plume. We found that the ejected particles strongly depend the irradiated
laser intensity. The spatial distribution of atomic density and the expansion velocity of each type of particle were estimated
from the spatiotemporal evolution of ablation particles. We also investigated a temperature of the aluminum fine particles
in liquid phase during the plume expansion by analyzing the slope of the L
II,III absorption edge in case of 1014-W/cm2 laser irradiation where the nanoparticles are most efficiently produced. The result suggests that the ejected particles travel
in a vacuum as a liquid phase with a temperature of about 2500 to 4200 K in the early stage of plume expansion. 相似文献
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Let G be a 2-dimensional connected, compact Abelian group and s be a positive integer. We prove that a classification of s-sheeted covering maps over G is reduced to a classification of s-index torsionfree supergroups of the Pontrjagin dual . Using group theoretic results from earlier paper we demonstrate its consequences. We also prove that for a connected compact group Y:
- (1)
- Every finite-sheeted covering map from a connected space over Y is equivalent to a covering homomorphism from a compact, connected group.
- (2)
- If two finite-sheeted covering homomorphisms over Y are equivalent, then they are equivalent as topological homomorphisms.
90.
Janne Heittokangas Katsuya Ishizaki Kazuya Tohge Zhi-Tao Wen 《Israel Journal of Mathematics》2018,227(1):397-421
An exponential polynomial of order q is an entire function of the form where the coefficients Pj(z),Qj(z) are polynomials in z such that It is known that the majority of the zeros of a given exponential polynomial are in domains surrounding finitely many critical rays. The shape of these domains is refined by showing that in many cases the domains can approach the critical rays asymptotically. Further, it is known that the zeros of an exponential polynomial are always of bounded multiplicity. A new sufficient condition for the majority of zeros to be simple is found. Finally, a division result for a quotient of two exponential polynomials is proved, generalizing a 1929 result by Ritt in the case q = 1 with constant coefficients. Ritt’s result is closely related to Shapiro’s conjecture that has remained open since 1958.
相似文献
$$g(z) = {P_1}(z){e^{{Q_1}(z)}} + ...{P_k}(z){e^{{Q_k}(z)}},$$
$$\max \{ deg({Q_j})\} = q.$$