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41.
Fumihisa Kobayashi Teruya Maki Yoshitoshi Nakamura Kazumasa Ueda 《Analytical sciences》2005,21(12):1553-1556
Phytoremediation is an innovative technology that utilizes the natural properties of plants to remediate hazardous waste sites. For more cost-effective phytoremediation, it is important to utilize a hyperaccumulating plant after phytoremediation, i.e. the recovery of valuable metals and the production of useful materials. In this work, the determination of metals in plant component polymers in a fern, Athyrium yokoscense, as a hyper-accumulating plant was established using steam explosion, Wayman's extraction method, and ICP emission spectrometry. After A. yokoscense plants were treated by steam explosion, the steam-exploded A. yokoscense were separated into four plant component polymers, ie. water-soluble material fraction, holocellulose fraction, methanol-soluble lignin fraction, and residual lignin fraction. The concentrations of Cu, Pb, Fe, and Zn in these plant component polymers and the dry weights of plant component polymers were measured. These analytical process determining metals in the plants will contribute to not only the evaluation and the efforts of phytoremediation using a hyperaccumulating plant, but also to the development of more effective phytoremediation. 相似文献
42.
Fragmentation of the pyridine ring followed by K-shell excitation/ionization has been studied with 2-fluoropyridine (2FPy) by electron impact. Ab initio molecular orbital (MO) calculations were also carried out to investigate the electronic states correlating with specific fragment ions. The fragment ions are produced characteristically at the N 1s edge, while the spectra observed at the F 1s and C 1s edges exhibit a small difference from that at the valence ionization. The production of the C(4)H(2)(+), C(4)H(3)(+) and C(4)H(2)F(+) ions indicates that the cleavage of the N-C6 and C2-C3 bonds or the N-C2 and C5-C6 bonds is likely to occur after the N 1s excitation/ionization. Ab initio MO calculations indicate that the former fission is likely to proceed through the n(N)(1)π(2)(1)π(3)(2) and n(N)(0)π(2)(2)π(3)(2) excited states of the parent molecular dication. On the other hand, the breakage of the N-C2 and C4-C5 bonds, which specifically proceeds at the N 1s edge for 2-methylpyridine, does not occur for 2FPy. The present calculation reveals that the products of this channel are unstable by the electronegativity of fluorine and that the relative energy of the Auger-final states of 2FPy is lowered by the reorganization and electron correlation effects. 相似文献
43.
In this paper, we characterize the nonnegative irreducible tridiagonal matrices and their permutations, using certain entries in their primitive idempotents. Our main result is summarized as follows. Let d denote a nonnegative integer. Let A denote a matrix in R and let denote the roots of the characteristic polynomial of A. We say A is multiplicity-free whenever these roots are mutually distinct and contained in R. In this case Ei will denote the primitive idempotent of A associated with thetai(0?i?d). We say A is symmetrizable whenever there exists an invertible diagonal matrix Δ∈R such that ΔAΔ-1 is symmetric. Let Γ(A) denote the directed graph with vertex set {0,1,…,d}, where i→j whenever i≠j and Aij≠0.Theorem.Assume that each entry ofAis nonnegative. Then the following are equivalent for0≤s,t≤d.
- (i)
- The graphΓ(A)is a bidirected path with endpointss,t:s↔*↔*↔?↔*↔t.
- (ii)
- The matrixAis symmetrizable and multiplicity-free. Moreover the(s,t)-entry ofEitimes(θi-θ0)?(θi-θi-1)(θi-θi+1)?(θi-θd)is independent of i for0≤i≤d, and this common value is nonzero.
44.
Let F denote a field and let V denote a vector space over F with finite positive dimension. We consider a pair of linear transformations A:V→V and A∗:V→V that satisfy the following conditions: (i) each of A,A∗ is diagonalizable; (ii) there exists an ordering of the eigenspaces of A such that A∗Vi⊆Vi-1+Vi+Vi+1 for 0?i?d, where V-1=0 and Vd+1=0; (iii) there exists an ordering of the eigenspaces of A∗ such that for 0?i?δ, where and ; (iv) there is no subspace W of V such that AW⊆W, A∗W⊆W, W≠0, W≠V. We call such a pair a tridiagonal pair on V. It is known that d=δ and for 0?i?d the dimensions of coincide. The pair A,A∗ is called sharp whenever . It is known that if F is algebraically closed then A,A∗ is sharp. In this paper we classify up to isomorphism the sharp tridiagonal pairs. As a corollary, we classify up to isomorphism the tridiagonal pairs over an algebraically closed field. We obtain these classifications by proving the μ-conjecture. 相似文献
45.
Kazuharu Sugawara Naoto Kamiya George Hirabayashi Hideki Kuramitz 《Analytical sciences》2005,21(8):897-900
Avidin, which is one type of glycoprotein, has a strong affinity with biotin (Ka = 10(15) M(-1)). Iminobiotin also forms a complex with avidin (Ka = 10(8) M(-1) at pH 9.5). The avidin-iminobiotin complex changes to the avidin-biotin complex in the presence of biotin because of the difference of the binding constant to avidin. In this study, the interaction between avidin and iminobiotin labeled with an electroactive compound was investigated by voltammetry. After avidin and the labeled iminobiotin (LI) were incubated in 0.1 M phosphate buffer (pH 7.0), the peak currents of LI were measured in various concentrations of biotin. The peak currents increased with increasing the concentration of biotin. Thus, this observation indicates the formation of avidin-biotin complex. On the other hand, the formation of avidin-iminobiotin complex depended on the pH of the solution. LI combines with the avidin at pH 5.6-8.9 and dissociates at pH 4.6. 相似文献
46.
Mikihito Hirabayashi 《manuscripta mathematica》2002,109(2):223-227
We give a relative class number formula for an imaginary abelian number field by means of some ``Dedekind sum'. This is
a generalization of Carlitz and Olson's formula presented in 1955.
Received: 18 December 2001 / Revised version: 15 May 2002
Mathematics Subject Classification (2000): 11R29, 11R20 相似文献
47.
48.
K. Morigaki Y. Sano I. Hirabayashi M. Konagai M. Suzuki 《Solid State Communications》1982,43(10):751-755
The position of the energy level of dangling bond centres and its broadening have been investigated by optically detected magnetic resonance measurements in aSi, aSi:H and aSi:H, F. Correlation between level broadening and increase in the bandgap energy is discussed. 相似文献
49.
In this note, inequalities between the distance degrees of distance degree regular graphs and to characterize the graphs when one of the equalities holds are proved. 相似文献
50.
A. Maki S. Mikamo M. Ono M. Takasaki A. Yamamoto H. Hirabayashi S. Kurokawa A. Kusumegi S. Higashi F. Kajino Y. Kawashima M. Nakashita S. Ozaki T. Takahashi Y. Teramoto S. Yamamoto S. Naito Y. Sakai M. Mishina 《Physics letters. [Part B]》1981,106(5):423-427
Direct production of single electrons in proton-nucleus collisions at 13 GeV/c has been measured. A rising ratio with decreasing pT above the 10?4 level is observed for low pT single electrons. The source of the rising ratio at low ratio at low pT is discussed in connection with the low mass dielectron continuum below the ? mass region. 相似文献