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31.
We developed a sensitive analytical method and an efficient clean-up method to quantify 3,6-dinitrobenzo[e]pyrene (3,6-DNBeP) in surface soil and airborne particles. After purification using a silica gel column and two reversed-phase columns, 3,6-DNBeP was reduced to 3,6-diaminobenzo[e]pyrene by a catalyst column and analyzed by high-performance liquid chromatography (HPLC) with a fluorescence detector. 3,6-DNBeP was detected in all of the soil samples and airborne particles examined. The concentration of 3,6-DNBeP in surface soil and airborne particles was determined in the ranges of 347-5007 pg/g of soil and 137-1238 fg/m3, respectively. 相似文献
32.
A series of osmate (OsO42−) core dendrimers was prepared by an ion-exchange technique through the mixing of K2OsO4 and a bis(quaternary ammonium bromide) core dendrimer, which consisted of poly(benzyl ether) dendron. By employing an osmate core dendrimer as a homogeneous catalyst, dihydroxylation reactions of olefins proceeded rapidly, and the dendritic osmium catalyst was recovered by reprecipitation and then reused. Furthermore, a dendritic effect on the recyclability of a catalyst was observed. In the case of asymmetric dihydroxylation reactions, the corresponding diol was obtained in a high chemical yield with a fair enantiomeric excess (ee). In this case, not only the dendritic osmium catalyst but also the chiral ligand could be recovered by reprecipitation and reused efficiently up to five times. 相似文献
33.
Ochiai M Nishi Y Hashimoto S Tsuchimoto Y Chen DW 《The Journal of organic chemistry》2003,68(20):7887-7888
In the presence of triethylamine, (Z)-(2-acetoxy-1-alkenyl)phenyl-lambda(3)-iodanes react with thioureas or thioamides in MeOH to give 2,4-disubstituted thiazoles directly in good yields. The reaction probably involves generation of highly reactive alpha-lambda(3)-iodanyl ketones through ester exchange of the beta-acetoxy group with liberation of methyl acetate, followed by nucleophilic substitutions with thioureas or thioamides. 相似文献
34.
Masato Goto Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):7-11
In the crystals of the five title compounds, tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(ethanol‐O)dicopper(II)–ethanol (1/2), [Cu2(C6H11O2)4(C2H6O)2]·2C2H6O, (I), tetrakis(μ‐3,3‐dimethylbutyrato‐O:O′)bis(2‐methylpyridine‐N)dicopper(II), [Cu2(C6H11O2)4(C6H7N)2], (II), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (III), tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(4‐methylpyridine‐N)di‐copper(II), [Cu2(C6H11O2)4(C6H7N)2], (IV), and tetrakis‐(μ‐3,3‐dimethylbutyrato‐O:O′)bis(3,3‐dimethylbutyric acid‐O)dicopper(II), [Cu2(C6H11O2)4(C6H12O2)2], (V), the dinuclear CuII complexes all have centrosymmetric cage structures and (IV) has two independent molecules. The Cu?Cu separations are: (I) 2.602 (3) Å, (II) 2.666 (3) Å, (III) 2.640 (2) Å, (IV) 2.638 (4) Å and (V) 2.599 (1) Å. 相似文献
35.
Hiroo Nakagawa Yoshiyuki Kani Masanobu Tsuchimoto Shigeru Ohba Hideaki Matsushima Tadashi Tokii 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):12-16
In the crystals of bis(pyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C5H5N)2], (I), the dinuclear CuII complexes have cage structures with Cu?Cu distances of 2.632 (1) and 2.635 (1) Å. In the crystals of bis(2‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (II), bis(3‐methylpyridine‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C6H7N)2], (III), and bis(quinoline‐N)tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II), [Cu2(C5H11O2Si)4(C9H7N)2], (IV), the centrosymmetric dinuclear CuII complexes have a cage structure with Cu?Cu distances of 2.664 (1), 2.638 (3) and 2.665 (1) Å, respectively. In the crystals of catena‐poly[tetrakis(μ‐trimethylsilylacetato‐O:O′)dicopper(II)], [Cu2(C5H11O2Si)4]n, (V), the dinuclear CuII units of a cage structure are linked by the cyclic Cu—O bonds at the apical positions to form a linear chain by use of a glide translation. 相似文献
36.
We study the q-difference analogue of the sixth Painlevé equation (q-PVI) by means of tau functions associated with the affine Weyl group of type D5. We prove that a solution of q-PVI coincides with a self-similar solution of the q-UC hierarchy. As a consequence, we obtain in particular algebraic solutions of q-PVI in terms of the universal character which is a generalization of the Schur polynomial attached to a pair of partitions. 相似文献
37.
Teruhisa Kadokami 《Topology and its Applications》2008,155(15):1699-1707
We introduce the norm and the order of a polynomial and of a homology lens space. We calculate the norm of the cyclotomic polynomials, and apply it to lens surgery problem for a knot whose Alexander polynomial is the same as an iterated torus knot. 相似文献
38.
Masayoshi?OkuboEmail author Teruhisa?Fujibayashi Masahiro?Yamada Hideto?Minami 《Colloid and polymer science》2005,283(9):1041-1045
Snowman/confetti-shaped, micron-sized, monodisperse composite particles were prepared by seeded dispersion polymerizations of n-butyl methacrylate (nBMA) with 1.28 and 2.67 m-sized polystyrene (PS) seed particles, respectively, in an ethanol/water (80/20, w/w) medium. These nonspherical composite particles consisted of one or several poly(nBMA) protuberances on the surfaces of the spherical PS particles.Part CCLXII of the series Studies on Suspension and Emulsion 相似文献
39.
Inspired by recent experiments of molecular motors, a dynamical systems model for a flexible machine is proposed which converts injected energy to output directional motion. The output amount is distributed broadly, and thus the coupling between input energy and output motion is loose, as in the experiments. This energy conversion is shown to be robust against the change of surrounding environment. Stability analysis on the fixed point solutions of the model is presented, which suggests that transient chaotic motion, induced by temporal three-body motion, is relevant to the energy conversion. 相似文献
40.
Teruhisa Tsuda 《Advances in Mathematics》2005,197(2):587-606
The universal character is a generalization of the Schur polynomial attached to a pair of partitions; see (Adv. Math. 74 (1989) 57). We prove that the universal character solves the Darboux chain. The N-periodic closing of the chain is equivalent to the Painlevé equation of type . Consequently we obtain an expression of rational solutions of the Painlevé equations in terms of the universal characters. 相似文献