Showing papers by "Nankai University published in 1989"
TL;DR: In this article, the authors discuss the viability of a global differential inclusion problem and show that a natural tanegential condition is necessary and sufficient for the existence of such a global solution.
41 citations
TL;DR: In this paper, 11 complexes having the general formula, [π-C 5 H 5 Fe(CO) 2 ] 2 [RC 6 H 4 C(O)N 2 -CHC 6H 4 O]Sn have been synthesized.
28 citations
TL;DR: In this article, a single crystal X-ray diffraction study of the Ph2SnL complex with R=o-NH2 confirms the molecular structure of the complex and reveals that the disappearance of the bands assigned to carbonyl unambiguously confirms that the ligands coordinate with the tin in the enol form.
23 citations
TL;DR: In this article, the authors developed the Kauffman's state model for the Jones polynomial, which uses diagrams looking like Feynman diagrams for scattering, into a systematic, diagrammatic approach to new link polynomials.
Abstract: By employing techniques familiar to particle physicists, we develop Kauffman’s state model for the Jones polynomial, which uses diagrams looking like Feynman diagrams for scattering, into a systematic, diagrammatic approach to new link polynomials. We systematize the ansatz for S matrix by symmetry considerations and find a natural interpretation for CPT symmetry in the context of knot theory. The invariance under Reidemeister moves of type III, II and I can be imposed diagrammatically step by step, and one obtains successively braid group representations, regular isotopy and ambient isotopy invariants from Kauffman’s bracket polynomials. This procedure is explicitiy carried out for the N=3 and 4 cases. N being the number of particle labels (or charges). With appropriate symmetry ansatz and with annihilation and creation included in the S matrix, we have obtained link polynomials which generalize the definition of the Akutzu-Wadati polynomials from closed braids to any oriented knots or links with explicit invariance under Reidemeister moves.
20 citations
TL;DR: The relation between harmonic functions and the characteristic operator of a Markov process is discussed in this paper, where the authors also consider the Dirichlet boundary condition at any regular boundary point of the state space.
Abstract: Given a Markov process satisfying certain general type conditions, whose paths are not assumed to be continuous. LetD be an open subset of the state spaceE. Any bounded function defined on the complement ofD extends to be a function onE such that it is harmonic inD and satisfies the Dirichlet boundary condition at any regular boundary point ofD. The relation between harmonic functions and the characteristic operator of the given process is discussed.
18 citations
TL;DR: In this article, a binuclear cobalt carbonyl complex with mixed valence Co 0 Co I (μ-Ph 2 Ppy) 2 (μCO)(CO)Cl has been determined by X-ray diffraction.
16 citations
TL;DR: In this paper, a computer assisted method for mobile phase selection for the optimal separation of pesticides by HPTLC and HPLC is presented, based on a plot of solute retention value and separation criterion vs. binary mobile phase composition.
Abstract: A computer-assisted method is presented for mobile phase selection for the optimal separation of pesticides by HPTLC and HPLC. The system is based on a plot of solute retention value and separation criterion vs. binary mobile phase composition for graphic optimization. The result of HPTLC can be transposed to HPLC for optimal separation. The transposition equation is given.
14 citations
TL;DR: In this article, the X-ray diffraction crystal structural analysis of [(Ph 3 P=O) 5 LaCl] [FeCl 4 ] 2+ cation was shown that the coordination of PO groups to the lanthanide made the LnCl bond more reactive than that in LnCl 3, so that Lewis acids such as FeCl 3 could abstract chloride to give the title complexes.
14 citations
13 citations
01 Jan 1989
TL;DR: In this article, an alternative approach to the foundation of Matsuoka's theory, and with the insight thus gained, to attack the corresponding problem for the torus, is presented, which applies to surfaces of higher genus as well.
Abstract: INTRODUCTION Matsuoka studied in [7J, [8J, [9J the periodic solutions to a periodic system of differential equations en the plane. Based on the braiding information of known solutions, he obtained lower bounds for the number of extra periodic solutions, Some very interesting applications to subharmonic solutions of second order differential equations were given in [8J. The core of his method is Proposition 2 in §4 of [7J, which is an elaborate application of the Lefschetz fixed point theorem. This Proposition is in fact more naturally accessible from the Nielsen fixed point theory. The purpose of the present paper is to give (in §2) such an alternative approach to the foundation of Matsuoka's theory, and then, with the insight thus gained, to attack (in §3) the corresponding problem for the torus. For the convenience of the reader, some relevant material in Nielsen theory is reviewed in §1. In principle, our approach applies to surfaces of higher genus as well. We would like to emphasize the approach rather than the best possible estimates in various cases. So, in §2 we confine ourselves to recovering one of Matsuoka's estimates, and in §3 we will not go into the possible refinements of our estimates.
12 citations
TL;DR: A computer-assisted method is presented for quanternary-solvent mobile phase selection, based on Snyder's solvent selectivity triangle concept with a mixture-design statistical technique, for the optimal separation of O-ethyl, N-isopropyl phosphoro(thioureido)thioates in reversed-phase thin-layer chromatography and of nine pesticides in normal- phase thin- layer chromatography.
Abstract: A computer-assisted method is presented for quanternary-solvent mobile phase selection, for the optimal separation of O-ethyl, N-isopropyl phosphoro(thioureido)thioates in reversed-phase thin-layer chromatography and of nine pesticides in normal-phase thin-layer chromatography. The system is based on Snyder's solvent selectivity triangle concept with a mixture-design statistical technique. The optimization of the separation over the experimental region is based on a special polynomial estimated from seven experimental runs, using the Rf difference as the selection criterion. An excellent agreement is obtained between predicted data and experimental results.
TL;DR: In the presence of excess bromide ion (ionic strength 0.3) the reaction was second-order with rate constants ranging from 7.1 to 12 liter m −1 min−1 for the macrocyclic amines as mentioned in this paper.
TL;DR: In this paper, the IR, UV, fluorescence and powder X-ray spectra of the mixed crystals between coumarin and crystal lattice-controlling substances were compared with those of pure coumarins.
TL;DR: The surface enhanced Raman spectra of NO3− and B(OH)4− were obtained by adding metal ions to a silver sol containing these anions, and the enhancement factor was estimated to be 104-105.
Abstract: The surface-enhanced Raman spectra of NO3− and B(OH)4− were obtained by adding metal ions to a silver sol containing these anions, and the enhancement factor was estimated to be 104-105 for NO3−. We think this is because metal ions form a complex compound with NO3− on the surface of the silver particles, leading to the formation of an O–Ag bond via the lone pair of electrons of the NO3−. The Raman spectrum of this bond has been observed. In addition, a tentative method for testing for trace ions is proposed.
TL;DR: A population of n items consisting of d defectives and n d good ones is considered, where d is the maximum number of tests the group testing procedure requires to find the defectives in n items.
Abstract: Consider a population of n items consisting of d defectives and n d good ones. The problem is to find the d defectives by means of a sequence of group tests. We will call a set of items contaminated if it contains a t least one defective, pure if it contains no defective, and free if there is no information on it. Then a group test is a test on a given set with two possible outcomes: the set is identified either as a contaminated set or as a pure set. Let M,(d, n ) be the maximum number of tests the group testing procedure t requires to find the d defectives in n items. Define
TL;DR: A special catalyst with palladium in two different valence states was prepared by refluxing 8-aminoquinoline resin-bound palladium(II) complexes in an methanol-water solution as mentioned in this paper.
01 Jan 1989
TL;DR: Two new broad and strong Raman bands in the surface-enhanced Raman spectrum of pyridine adsorbed on colloidal silver particles were observed, one near 612 cm−1 and the other near 924 cm −1 as mentioned in this paper.
Abstract: Two new broad and strong Raman bands in the surface-enhanced Raman spectrum of pyridine adsorbed on colloidal silver particles were observed, one near 612 cm−1 and the other near 924 cm−1. It is concluded that these bands are caused by a boron compound in silver sol.
06 Sep 1989
TL;DR: A conjecture for the discrete approximation of the Papoulis-Gerchberg algorithm, in order to implement it for the extrapolation of one-dimensional bandlimited signals, has been suggested and proved in this article.
Abstract: Summary form only given. A conjecture for the discrete approximation of the Papoulis-Gerchberg algorithm, in order to implement it for the extrapolation of one-dimensional bandlimited signals, has been suggested and proved in the literature. The authors have extended these results to multidimensional bandlimited signals. The theorem is stated. >
TL;DR: In this paper, a study of methylation of inorganic tin by humic materials (humic and fulvic acids) isolated from the sediment of Tianjin Harbor, Tianjin, China, and the effects of pH, salinity and the concentration of INO on the production of methyltin were investigated.
Abstract: This paper presents a study of methylation of inorganic tin (SnCl4·5H2O) by humic materials (humic and fulvic acids) isolated from the sediment of Tianjin Harbor, Tianjin, China, and the effects of pH, salinity, and the concentration of inorganic tin on the production of methyltin were investigated.
These humic materials could methylate inorganic tin, and the methyltin product was mainly monomethyltin. Low molecular weight compounds of the humus fraction (i.e. fulvic acid) were more active in the methylation, which could be facilitated by salinity and affected by pH.
TL;DR: In this paper, a new kind of photoinduced conical light scattering with quasi-periodic oscillation was observed for the first time, which may be related to temporal-spatial changes in the photorefractive phase grating recorded by the incident laser beam along (or near) the -c direction and its reflected beam.
TL;DR: In this paper, the authors give results concerning a conjecture of Tong (1982) on the distribution of this random variable as a function of ρ and apply them to yield more general results for linear combinations of order statistics from elliptical distributions.
Abstract: Let X1,…,Xn be exchangeable normal variables with a common correlation p, and let X(1) > … > X(n) denote their order statistics. The random variable σni=n—k+1xi, called the selection differential by geneticists, is of particular interest in genetic selection and related areas. In this paper we give results concerning a conjecture of Tong (1982) on the distribution of this random variable as a function of ρ. The same technique used can be applied to yield more general results for linear combinations of order statistics from elliptical distributions.
Soient X1,…,Xn des variables aleatoires gaussiennes interchangeables, avec měme correlation P et X(1) > … > X(n)) ces variables placees en ordre croissant. La variable aleatoire σni=−k+1xi appelee differentielle de selection par les geneticiens, est importante dans la theorie de la selection genetique. On presente des resultats a propos ďune conjecture de Tong (1982) au sujet de la dependance, par rapport a ρ, de la loi de cette variable. La technique utilisee peut ětre appliquee afin ďobtenir des resultats plus generaux relativement a des combinaisons lineaires de statistiques ďordre provenant de distributions elliptiques.
TL;DR: In this paper, the methylation of tin (II) [Sn(II)] by iodomethane (CH3I) under environmental conditions has been further demonstrated by a 13C carbon isotope tracer method.
Abstract: The methylation of tin(II) [Sn(II)] by iodomethane (CH3I) under environmental conditions has been further demonstrated by a 13C carbon isotope tracer method. Methylation products are mainly monomethyltin, and very small amounts of dimethyltin. The reaction of Sn(II) and CH3I was investigated at pH 2, 4, 6, 8, 10 and salinity (S) 8, 15, 22, 28, 35%; it has been found the reaction was affected by pH and salinity, the tin methylation activity being highest at about pH 6 and S = 28% . The methylation reaction is first-order for both CH3I and Sn(II), and the rate equation has been obtained as follows:
.
TL;DR: The authors prove that J. Sanz and T. Huang's conjecture on bandlimited signal extrapolation with noise is indeed true and all hypotheses and notations used in the proof are described in detail.
Abstract: The authors prove that J. Sanz and T. Huang's (ibid., vol.ASSP-33, p.1338-41, Dec. 1983) conjecture on bandlimited signal extrapolation with noise is indeed true. All hypotheses and notations used in the proof are described in detail. >
TL;DR: In this paper, a four-step synthesis of 2E, 4Z)-2, 4-decadienoate (pear ester) from propargyl alcohol with a 50% total yield was described.
TL;DR: In this paper, superconducting Tl-Ca-Ba-Cu-O thin films were prepared by dc magnetron sputtering from a pair of Tl2Ca1Ba3Cu4Oy bulk targets.
Abstract: Superconducting Tl–Ca–Ba–Cu–O thin films have been prepared by dc magnetron sputtering from a pair of Tl2Ca1Ba3Cu4Oy bulk targets. The post-annealing films on ZrO2 ceramic substrates exhibit an onset temperature of about 125 K and zero resistance as high as 101 K. SEM showed a smooth terraced surface structure. The XRD analysis proved that the films were polycrystalline and were not single phase superconducting material.
TL;DR: In this paper, a new method of measuring two-photon absorption cross section by fitting the observed ionization decay curve is proposed, which is applicable not only to valence states but also to Rydberg states.
01 Jan 1989
TL;DR: In this paper, a hierarchy of integrable sys-tems is proposed based on an analysis of the loop algebra and the Hamiltonian structure of the new hierarchy of equations is established by means of constrained formal variational calculus.
Abstract: On the basis of an analysis of the loop algebra ?_1 a new hierarchy of integrable sys-tems is proposed. The Hamiltonian structure of the new hierarchy of equations is established by means of constrained formal variational calculus. This hierarchy of evolution equations is demonstrated to possess an infinite number of conserved densities, which are ininvolution in pairs.