Showing papers by "Wuhan University published in 1989"
TL;DR: In this paper, an SPE (solid polymer electrolyte)-based solid-state electrochemical oxygen gas sensor is presented, with a hydrophobic Teflon-bonded Pt back layer pressed on a piece of Nafion membrane.
27 citations
TL;DR: Pollen protoplasts isolated from cold-pretreated uninucleate pollen of Hemerocallis fulva were cultured in K3 basic medium with various supplements and microscopic observations revealed that there were equal and unequal first division and subsequent growth resulting in great divergence of the products.
22 citations
TL;DR: In this article, two new kinds of crown ethers, 4,4-dipentadecyl- or 4,3′0dipenadecyldibenzo-30crown-10 and 3-pentadecylbenzo-15-crown5, were coated on glass capillary columns and fused-silica capillary column, and their chromatographic characteristics were characterized.
20 citations
TL;DR: In this paper, a mono-condensed product (Fcen) was obtained from the condensation of ferrocenylformyl acetone with ethylenediamine and five new Fcen complexes of lanthanide chlorides having the formula fcen3LnC13 (where Ln = La, Nd, Gd, Dy and Lu) were synthesized via the reaction of Fcens with lanthanides.
19 citations
TL;DR: Protoplasts were isolated from mature pollen grains in Iris tectorium; Zephyranthes grandiflora and Hemerocallis fulva by an enzymatic technique and confirmed to viable by fluorochromatic reaction.
19 citations
TL;DR: A gas diffusion cell allowing ready access of reactant to the electrode through the thin electrolyte layer has been used to obtain in-situ infra-red spectra from adsorbed CO on Pt under conditions of sustained reaction.
18 citations
23 Apr 1989
TL;DR: A formal method for communication protocol specification is presented in which the best features of approaches using finite-state machines, communication sequential processes, and abstracting data types are combined.
Abstract: A formal method for communication protocol specification is presented in which the best features of approaches using finite-state machines, communication sequential processes, and abstracting data types are combined. First, the formal techniques of the communication protocol are briefly described. Then, the hybrid method of protocol specification is presented. Finally, an example, i.e IEEE 802.3 MAC protocol for a LAN described by the proposed formal method is given. >
14 citations
TL;DR: This paper examines the convergence behavior of different subdomain iteration procedures as well as different sub domain approximations for elliptic equations and shows that certain iterative procedures are equivalent to block Gauss-Siedel and Jacobi methods.
Abstract: Domain decomposition methods are a natural means for solving partial differential equations on multi-processors. The spatial domain of the equation is expressed as a collection of overlapping subdomains and the solution of an associated equation is solved on each of these subdomains. The global solution is then obtained by piecing together the subsolutions in some manner. For elliptic equations, the global solution is obtained by iterating on the subdomains in a fashion that resembles the classical Schwarz alternating method. In this paper, we examine the convergence behavior of different subdomain iteration procedures as well as different subdomain approximations. For elliptic equations, it is shown that certain iterative procedures are equivalent to block Gauss-Siedel and Jacobi methods. Using different subdomain approximations, an inner-outer iterative procedure is defined.M-matrix analysis yields a comparison of different inner-outer iterations.
13 citations
TL;DR: In this article, a method on the Darboux transformation in the form of a pole expansion is presented for finding soliton solutions of the modified nonlinear Schrodinger equation.
12 citations
TL;DR: Some eggs 5 days after culture of unfertilized ovules of sunflower show striking ultrastructural changes, which include nuclear migration, an increase in the number and activity of the organelles, a loss of polarity and wall formation at the chalazal end of the cell, indicating that parthenogenic development has been triggered in these eggs.
Abstract: Electron microscope studies have been conducted on the parthenogenesis induced by in vitro culture of unfertilized ovules of sunflower (Helianthus annuus). In comparison with the state of the egg prior to inoculation, some eggs 5 days after culture show striking ultrastructural changes, which include, among others, nuclear migration, an increase in the number and activity of the organelles, a loss of polarity and wall formation at the chalazal end of the cell. Most of these changes are similar to those that occur normally in the zygote, indicating that parthenogenic development has been triggered in these eggs. Such eggs have been termed activated and are presumed to be capable of undergoing parthenogenesis. The parthenogenic proembryos which result share some features in common with zygotic proembryos. In addition, some parthenogenic proembryos exhibit unique properties not found in zygotic proembryos. These include embryos that consist of two parts differing markedly in density, an inversion of polarity, the frequent occurrence of autophagic vacuoles, the thickening of cell walls, a centripetal growth mode of wall formation, the appearance of an incomplete cell wall, free nuclear division, amitosis and degeneration. We believe that these ultrastructural peculiarities are the effects of in vitro culture.
12 citations
TL;DR: In this article, simultaneous direction finding measurements of equatorial latitude whistlers have been performed in January 1988 at three stations in China; Zhanjiang (geomagnetic latitude 10.0°N), Guilin (14.1°) and Wuchang (19.4°).
TL;DR: Thermograms of growth metabolism, endogenous metabolism and non-growth metabolism of resting cells of E. coli were obtained using an LKB-2277 Bioactivity Monitor and thermokinetic equations for the various different kinds of metabolism in cells can be obtained by microcalorimetric methods.
TL;DR: In this article, the infrared cut-off wavelengths of CdF 2 PbCl 2 ǫ-KI are 9.5 μm and 18 μm, respectively.
Abstract: Some new mixed halide glasses, CdF 2 PbCl 2 , CdF 2 PbCl 2 , CdF 2 PbCl 2 KBr, CdBr 2 PbCl 2 KI and CdI 2 PbCl 2 KBr systems, were synthesized. Samples 4 mm thickness could be synthesized in the CdF 2 PbCl 2 and CdF 2 PbCl 2 KBr systems. The infrared cut-off wavelengths of CdF 2 PbCl 2 KI are 9.5 μm and 18 μm, respectively. The structure of CdF 2 PbCl 2 glass was studied by X-ray photoelectron spectroscopy, X-ray diffraction, and infrared and Raman spectral analysis. The Cd 2+ ion in the glasses is coordinated by F and Cl ions, the distance of two Cd 2+ ions being about 4.0 A and the FCdF angle about 60°. Compared with the [CdF 8 ] unit in the crystalline state the [CdX n ] units in glass have large deformations.
TL;DR: The dynamical theory of electron diffraction for crystals in the wave-optical and wave-mechanical formulations is extended to quasicrystals in this article, where the basic equations satisfied by the electron wave amplitudes have the same forms for both crystals and quasicirystals.
Abstract: The dynamical theory of electron diffraction for crystals in the wave-optical and the wave-mechanical formulations is extended to quasicrystals. In these formulations the basic equations satisfied by the electron wave amplitudes have the same forms for both crystals and quasicrystals.
Die dynamische Theorie der Elektronenbeugung fur Kristalle in der wellenoptischen und wellenmechanischen Darstellung wird fur den Fall der Quasikristalle erweitert. In beiden Darstellungen hat das von den Wellenfunktionen erfullte Gleichungssystem dieselbe Form sowohl fur den Fall der Quasikristalle als auch den der Kristalle.
TL;DR: In this article, the standard enthalpies of combustion at 298.15 K of tetraphenylporphyrin, tetra(p-methylphenyl) porphrin, tetrasmeth-oxyphenyl) porphyrin and tetrasp-naphrin were determined as −22223.2 ±6.8 and −21784.4±11.2 KJ mol−1 respectively.
TL;DR: In this paper, the effect of dislocations in a silicon single crystal on the zeroth-order Laue-zone (ZOLZ) pattern in large-angle convergent-beam electron diffraction (LACBED) has been studied experimentally.
Abstract: The effect of dislocations in a silicon single crystal on the zeroth-order Laue-zone (ZOLZ) pattern in large-angle convergent-beam electron diffraction (LACBED) has been studied experimentally. It is found that edge dislocations cause the ZOLZ pattern to be compressed or elongated and screw dislocations cause it to be dislocated. This phenomenon is the consequence of opposite shifts of the two halves of the Tanaka pattern, separated by the shadow image of the dislocation line along directions b and -b of the Burgers vector. The shift direction of each half of the pattern depends on the dislocation characteristics and the position of the incident-beam crossover. The pattern on the side, pointed to by the vector u × c (or -u × c) from the shadow image of the dislocation line is shifted along b (or -b), where u is the direction of the dislocation-line vector and c is a vector pointing to the beam crossover from the dislocation line. This phenomenon can be used to determine the Burgers vector (both its direction and sense) of a dislocation.
TL;DR: In this article, the Darboux transformation method is used to find soliton solutions of the Landau-Lifschitz equation of a classical Heisenberg spin chain.
Abstract: Darboux transformation method is used to find soliton solutions of the Landau-Lifschitz equation of a classical Heisenberg spin chain.
TL;DR: In this article, the synthesis of a tetradentate ligand was reported and the crystal structure of (Cu(BEEDA)(ClO 4 ))-ClO4 by the X-ray method was determined.
TL;DR: In this article, a gas-diffusion electrode was designed for in-situ ESR measurements, and the electrochemical and ESR data recorded in nitrogen and in air for a benzoquinone-modified carbon electrode indicate the involvement of surface semiquinone radicals in the oxygen reduction reaction.
TL;DR: This paper focuses on the identifiability problem of hydrological system modelling, taking implicit rainfall-runoff models as a target for study i.e. those models whose structures are nonlinear functions of their parameters.
Abstract: This paper focuses on the identifiability problem of hydrological system modelling, taking implicit rainfall-runoff models as a target for study i.e. those models whose structures are nonlinear functions of their parameters. Because most implicit models and objective functions are very difficult as regards analytical solution or for finding high-order derivatives, a numerical analysis method is developed which not only can assess the identifiability problem but also can provide useful information for dealing with parameter optimization. The major studies involved are two-fold: (1) proposing a mathematical description and assessment method for the structural identifiability of hydrological models; and (2) providing a workable and robust identification technique using a rotating transformation of the parameter space. Using both generated error-free and watershed data in China, it has been verified that the approach is of significance and usefulness.
TL;DR: In this paper, a flow-injection analyzer was used for simultaneous determinations of Lanthanum and the total quantities of the two ions with two spectrophotometers by using 2-(2-arsenophenylazo)-7-(2,4,6,-trichlorophenylazos)-1, 8-dihydroxy-naphthalene-3,6-disulfonic acid and 2-( 2-phosphono-4-chlorophenylozamide)-7-, 4-fluorphenylazo-1,8
TL;DR: The structural changes of the high-Tc superconductor YBaCuO between 100 and 300 K are studied by positron lifetime and Doppler broadening measurements as a function of temperature as mentioned in this paper.
Abstract: The structural changes of the high-Tc superconductor YBaCuO between 100 and 300 K are studied by positron lifetime and Doppler broadening measurements as a function of temperature. There are anomalous changes in the positron lifetimes and Doppler broadening S-parameters near 130 and 260 K, which is consistent with some reported experimental results. These anomalies may be cause by the lattice instabilities, such as the ordering readjustment of oxygen vacancies.
Die strukturellen Anderungen des Hoch-Temperatur-Supraleiters YBaCuO wurden als Funktion der Temperatur zwischen 100 und 300 K mit Positronenlebensdauer- und Dopplerverbreiterungsmessungen untersucht. Es treten anomale Anderungen in der Positronenlebensdauer und im Dopplerparameter S nahe 130 and 260 K auf, was konsistent mit anderen experimentellen Ergebnissen ist. Diese Anomalien konnen durch Gitterinstabilitaten, wie die Wiederherstellung der Ordnung von Sauerstoffleerstellen, verursacht werden.
TL;DR: In this article, the ionic conduction in NBAL glasses has been studied based on their Raman spectroscopy, and the effect of composition and structure of the glasses on their ionic conductivity is discussed.
Abstract: New glasses have been prepared in the K2NbOFAlF3(NBAL) system, with the IR spectrum, UV spectrum and the thermal properties measured. The ionic conduction in NBAL glasses has been studied. Based on their Raman spectroscopy, the structure of the glasses is briefly studied. The effect of composition and structure of the glasses on their ionic conductivity is discussed. When the AlF3 content ranges from 21 to 29 mol%, Al3+ and Nb5+ ions are octahedrally coordinated, and the ionic conductivity increases with the AlF3 content. When the AlF3 content reaches 29 mol%, part of the Al3+ ions are tetrahedrally coordinated and the ionic conductivity decreases. The effect is attributed to the formation of AlF−4 which block the moble ion channels. The ionic conductivity of glasses in this system is 1.045 × 10 −2 Ω −1 · cm −1 at 194°C.
09 Nov 1989
TL;DR: A technique is described for segmenting B-scan images to extract a tissue signature by texture analysis, using Gray-level sum and difference histograms and a K-mean clustering algorithm to partition the image into homogeneous zones of texture.
Abstract: A technique is described for segmenting B-scan images to extract a tissue signature by texture analysis. Gray-level sum and difference histograms are used to extract texture features. A K-mean clustering algorithm is used to partition the B-scan image into homogeneous zones of texture. The performance of the method is tested by the analysis of natural texture and abdominal images. >
TL;DR: In this article, the linear relation between the quantity of electric charge due to the electrochemical reaction, Q, and w−12, the reciprocal of the square root of the angular velocity of rotation, was verified theoretically, according to the convective diffusion equation for a rotating disk electrode.
TL;DR: In this paper, diamond-like carbon films were prepared on quartz glass by rf plasma glow discharge CVD from C 6 H 6 +Ar(H 2 ) Boron doping was done by ion implantation Both the resistivity and optical gaps of the films decrease as the implantation dose increases.
TL;DR: In this article, the inverse scattering method with the direct method of Hirota was used to obtain explicit N-soliton solutions of the Korteweg-de Vries equation and the nonlinear Schrodinger equation.
Abstract: By using the technique of determinant calculation, explicit N-soliton solutions of the Korteweg–de Vries equation and the nonlinear Schrodinger equation are obtained for arbitrary N in terms of the inverse scattering method. Therefore, the relations of the inverse scattering method with the direct method of Hirota become easy to be understood.