Inherent-opening-controlled pattern formation in carbon nanotube arrays

We have introduced inherent openings into densely packed carbon nanotube arrays to study self-organized pattern formation when the arrays undergo a wetting–dewetting treatment from nanotube tips. These inherent openings, made of circular or elongated hollows in nanotube mats, serve as dewetting centres, from where liquid recedes from. As the dewetting centres initiate dry zones and the dry zones expand, surrounding nanotubes are pulled away from the dewetting centres by liquid surface tension. Among short nanotubes, the self-organized patterns are consistent with the shape of the inherent openings, i.e. slender openings lead to elongated trench-like structures, and circular holes result in relatively round nest-like arrangements. Nanotubes in a relatively high mat are more connected, like in an elastic body, than those in a short mat. Small cracks often initialize themselves in a relatively high mat, along two or more adjacent round openings; each of the cracks evolves into a trench as liquid dries up. Self-organized pattern control with inherent openings needs to initiate the dewetting process above the nanotube tips. If there is no liquid on top, inherent openings barely enlarge themselves after the wetting–dewetting treatment

Mesophilic and thermophilic methane fermentation of Euphorbia tirucallis

La méthanisation d'#Euphorbia tirucalli$ a été réalisée en conditions mésophile et modérément thermophile. Trois différents pré-traitements de cette plante ont été testés : simple fragmentation, broyat, séchage puis broyage. Les digesteurs ont été alimentés avec 5 % de matière sèche en batch. Lors d'une expérimentation de 35 jours, le meilleur rendement (0,78 1/1/j) a été obtenu avec les fragments de plante en condition thermophile modérée. (Résumé d'auteur

First report of Rice stripe necrosis virus infecting rice in Benin

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Effect of timely application of alternated treatments of Bacillus thuringiensis and neem on agronomical particulars of cabbage

Diamondback moth (DBM) Plutella xylostella is an economical pest of cabbage. Chemical pesticides constitute so far the major tool for pest management. However, the use of botanical pesticides and microbial is also considered. The objective of this study was to compare the effect of alternating treatments of Bacillus thuringiensis and Neem on agronomic particulars of cabbage as compared to solo and chemical applications. Results showed that the alternation of B. thuringiensis and Neem, performed as well as solo. Agronomic parameters were strongly related to the level of infestation of P. xylostella and other pests. The number of leaves was higher in the control and Dimethoate treatments depicting higher response to severe damages, whereas diameters of cabbage heads were higher in the Biobit and Neem treatments. There was no significant difference between the Biobit and the alternated treatment in terms of weight of cabbage. The diameter of cabbage treated with Biobit was higher than those treated with an alternated treatment. However, there was no significant difference between the alternated treatment and Neem. On the other hand, there was significant correlation between agronomic parameters and the presence of parasitoids. The correlation was significantly greater between the number of leaves, diameter and weight of cabbage in the presence of Oomyzus sokolowskii. These results indicate that timely application of alternated treatments of B. thuringiensis and Neem can be more economically viable as compared to single treatments and should be adopted in integrated pest management programs for cabbage. (Résumé d'auteur

An effective long-range attraction between protein molecules in solutions studied by small angle neutron scattering

Small angle neutron scattering intensity distributions taken from cytochrome C and lysozyme protein solutions show a rising intensity at very small wave vector, Q, which can be interpreted in terms of the presence of a weak long-range attraction between protein molecules. This interaction has a range several times that of the diameter of the protein molecule, much greater than the range of the screened electrostatic repulsion. We show evidence that this long-range attraction is closely related to the type of anion present and ion concentration in the solution

Effects of kinked linear defects on planar flux line arrays

In the hard core limit, interacting vortices in planar type II superconductors can be modeled as non-interacting one dimensional fermions propagating in imaginary time. We use this analogy to derive analytical expressions for the probability density and imaginary current of vortex lines interacting with an isolated bent line defect and to understand the pinning properties of such systems. When there is an abrupt change of the direction of the pinning defect, we find a sinusoidal modulation of the vortex density in directions both parallel and perpendicular to the defect.Comment: 13 figure

Boson Peak in Deeply Cooled Confined Water: A Possible Way to Explore the Existence of the Liquid-to-Liquid Transition in Water

The boson peak in deeply cooled water confined in nanopores is studied with inelastic neutron scattering. We show that in the (P, T) plane, the locus of the emergence of the boson peak is nearly parallel to the Widom line below ∼1600  bar. Above 1600 bar, the situation is different and from this difference the end pressure of the Widom line is estimated. The frequency and width of the boson peak correlate with the density of water, which suggests a method to distinguish the hypothetical “low-density liquid” and “high-density liquid” phases in deeply cooled water.United States. Dept. of Energy (Grant DE-FG02-90ER45429