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The hollow porous MgO microspheres have been synthesized through a simple in situ chemical vapor deposition method, and the investigations reveal that Zn in raw source is key and possibly acts as a...

In this Note we report the attempt of improving the Mimura–Sakaguchi–Matsushita (MSM) model of bacterial colony formation by revising the nonlinear diffusion term in the reaction diffusion equation. Using this revised MSM model, all five typical colony patterns are reproduced and the experimental morphological diagram of colony patterns are completely simulated. During the last few decades, much attention has been paid to self-assembly pattern formation in various fields. Among them, pattern formation in biological systems is the most sophisticated and interesting. Due to the complexity of biological systems, recoganizing the mechanism of pattern formation in biological systems is difficult. Therefore, investigation of simple biological objects, which is dominated by purely physical conditions, is a good choice. Here we focus on bacterial colony formation, which is one of the simplest biological objects. It is known that some kinds of bacteria such as Bacillus subtilis (B. subtilis) exhibit various colony patterns on an agar medium by changing the incubation conditions, i.e., the concentration of agar Ca and that of nutrient Cn in the medium. Cn determines the rate of division of active bacteria, and Ca controls the motivebility of bacteria. Ohgiwari et al. completed an experimental morphological diagram (see Fig. 1). It can be seen from region A (high Ca and low Cn) of Fig. 1 that the colony pattern exhibits tip-splitting growth with diffusion-limitted aggregation (DLA)-like ramified structures. Keeping a high Ca and increasing Cn (region B),the pattern becomes round with Eden-like rough interface. If Cn is high and Ca is low (region D), the pattern looks macroscopically disklike. The colony growth in region D is consistent with the solution of the two-dimentional Fisher equation. In region E, which is between regions A and D, the pattern shows highly branched structures similar to the dense-branching morphology (DBM). When Cn is high and Ca takes an appropriate intermediate value (region C), colony exhibits concentricring patterns which are produced alternately in the active state and inactive state of the bacteria. In order to explain these observations, various reaction diffusion models have been proposed. The MSM model is one of them, which is based on the assumption that there exist two types of bacteria; active ones that move, grow and divide, and inactive ones that do nothing at all. Using the MSM model with linear diffusion patterns A, C, D and E are reproduced. Using MSM model with nonlinear diffusion, pattern B is also generated. In the MSM model, the relation among the population density of active bacteria u, the density of the inactive bacteria w, and the nutrient concentration v is expressed by a set of equations as

Many structure parameters have been suggested to predict the synchronizability of complex networks. They were qualitatively suitable for certain networks but failed for others. Based on the coupled oscillator model, we find that the homogeneity of load distribution determines the synchronizability of complex networks, and the standard deviation of edge betweenness centrality is coincident with synchronizability for various complex networks. These results suggest that in order for a network to hence to synchronize more effectively, the load distribution must be more homogeneous.

We present a current-controlled branching method for the fabrication of anodic aluminum oxide (AAO) templates with a triply-branched nanopore structure. By controlling the current density in the branching process, a regular triply-branched nanopore array structure was obtained in the AAO template conveniently and precisely. Based on this template, a regular tripod Ni–P amorphous nanorod array was fabricated by electroless deposition. The present method is particularly advantageous for the fabrication of templates and materials with a complex and accurate multiply branched nanostructure.

The structure factors a(Q) of liquid metals, Zn, Cd, and Hg are calculated by using the hard sphere cluster model. The calculated concentration and relative sizes of the two kinds of hard spheres, which correspond to the two kinds of clusters, respectively, coincide with the characteristics of solid structures. Die Strukturfaktoren a(Q) fur die flur die flussigen Metalle Zn, Cd und Hg, werden nach dem Hartkugel-Clustermodell berechnet. Die Berechnungsergebnisse sind in guter Ubereinstimmung mit den Versuchsergebnissen. Die berechneten Konzentrationen und relativen Grosen der beiden Arten harter Kugeln, die den beiden Clusterarten entsprechen, stimmen mit den Festkorperstrukturcharakteristiken uberin.

A simple approach is presented to calculate the temperature dependence of the static structure factor for non-simple liquid metals, based on the hard sphere cluster model and considering the temperature dependence of the hard sphere diameters and atomic percentage of the second type of clusters. The structure factors of liquid metals are calculated for Bi (T = 300, 500, 550, 800, and 950 °C), Ga (T = 50, 200, 550, 800, and 1000 °C), Sb (T = 660 and 800 °C), and Sn (T = 250, 300, 700, 900, and 1100 °C). The calculated results are in good agreement with experiments. Eine einfache Methods zur Berechnung der Temperaturabhangigkeit des statischen Strukturfaktors von nicht-einfachen flussigen Metallen wird vorgeschlagen, die auf Modellen von Clustern aus harten Kugeln beruht, wobei die Temperaturabhangigkeit der Durchmesser der harten Kugeln sowie der Atom-Prozentsatz der zweiten Clusterart berucksichtigt wird. Die Strukturfaktoren fur flussiges Bi (T = 300, 500, 550, 800 und 950 °C), Ga (T = 50, 200, 550, 800 und 1000 °C), Sb (T = 660 und 800 °C) und Sn (T = 250, 300, 700, 900 und 1100 °C) werden berechnet. Die theoretischen Ergebnisse erweisen sich in guter Ubereinstimmung mit experimentellen Daten.

The hard sphere cluster model is used to study the dependence of the structure factors upon temperature for liquid metals with the second type of liquid structures. The structure factors for liquid Zn (T = 450, 560, and 660 °C) and Hg (T = −35, 0, 20, 80, 150, 200, and 250 °C) are calculated. The theoretical results are in good agreement with experiments. Das Hartkugelclustermodel wird benutzt, um die Temperaturabhangigkeit des Strukturfaktors fur flussige Metalle vom zweiten Flussigstrukturtyp zu untersuchen. Die Strukturfaktoren fur flussiges Zn (T = 450, 560 und 660 °C) und Hg (T = −35, 0, 20, 80, 150, 200 und 250 °C) werden berechnet. Die theoretischen Resultate sind in guter Ubereinstimmung mit den experimentellen Daten.

A simple theoretic expression for the static structure factor a(Q) of non-simple liquid metals is presented, based on the hard sphere cluster model. This expression is a superposition of two Ash-croft-Lekner expressions with weight factors representing the atomic percentage of each type of clusters. The structure factors of liquid Bi, Ga, Sb, and Sn are computed. The calculated results are in good agreement with experiments over the entire range of momentum space. Ein einfacher theoretischer Ausdruck fur den statischen Strukturfaktor a(Q) von nicht-einfachen flussigen Metallen wird vorgeschlagen, der auf Modellen von Clustern von harten Kugeln beruht. Der Ausdruck ist eine Uberlagerung von zwei Ashcroft-Lekner-Ausdrucken, deren Gewichtsfaktoren den Atom-Prozenten der beiden Clusterarten entsprechen. Die Strukturfaktoren fur flussiges Bi, Ga, Sb und Sn werden berechnet. Die theoretischen Ergebnisse sind in guter Ubereinstimmung mit experimentellen Daten im gesamten Q-Vektor-Bereich.

X-ray atomic form factors, f, have been calculated for crystalline and free-atom lithium using the same Gaussian-orbital basis and the same exchange-correlation potential in the local density approximation by the self-consistent linear combination of Gaussian orbitals (LCGO) method. The difference between f calculated for an Li crystal and f for free Li atoms is less than 0.8%, which is rather small. For free Li atoms the values of f deviate from those obtained by Hartree-Fock calculations by 1.5 to 3% for sin θ/λ < 1.2 A-1.