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The repellent effect of necrotic tissues on the nematode Pratylenchus penetrans (Cobb, 1917), Filipjev and Schuurmans Stekhoven, 1941 /
Aspect ratio dependence of heat transport by turbulent Rayleigh-B\'{e}nard convection in rectangular cells
We report high-precision measurements of the Nusselt number as a
function of the Rayleigh number in water-filled rectangular
Rayleigh-B\'{e}nard convection cells. The horizontal length and width
of the cells are 50.0 cm and 15.0 cm, respectively, and the heights ,
25.0, 12.5, 6.9, 3.5, and 2.4 cm, corresponding to the aspect ratios
, , ,
, , and . The measurements were carried out
over the Rayleigh number range and the
Prandtl number range . Our results show that for
rectangular geometry turbulent heat transport is independent of the cells'
aspect ratios and hence is insensitive to the nature and structures of the
large-scale mean flows of the system. This is slightly different from the
observations in cylindrical cells where is found to be in general a
decreasing function of , at least for and larger. Such a
difference is probably a manifestation of the finite plate conductivity effect.
Corrections for the influence of the finite conductivity of the top and bottom
plates are made to obtain the estimates of for plates with
perfect conductivity. The local scaling exponents of are calculated and found to increase from 0.243 at
to 0.327 at .Comment: 15 pages, 7 figures, Accepted by Journal of Fluid Mechanic
Bearing fault diagnosis based on Shannon entropy and wavelet package decomposition
A new feature extraction method based on WPD and Entropy is proposed in this paper. Firstly, WPD is utilized to decompose the signal into different frequency bands to obtain different frequency sub-signal. Secondly, root-mean-squire (RMS) value, kurtosis (K) and peak factor (PF) parameters are extracted from each sub-signal to obtain the fault feature vector. Thirdly the Entropy of each feature vector is calculated to realize the bearing fault diagnosis. Finally, experimental results indicate that the bearing fault diagnosis method proposed in this paper is effective
Commentary: Multiscale Analysis of Independent Alzheimer's Cohorts Finds Disruption of Molecular, Genetic, and Clinical Networks by Human Herpesvirus
Semileptonic Decays to and in Bethe-Salpeter Method
Using the relativistic Bethe-Salpeter method, the electron energy spectrum
and the semileptonic decay widths of and
are calculated. We obtained large branching
ratios, and , which can be easily detected in the future
experiment.Comment: 3 pages, 3 figures
1,3-Bis(chloromethyl)-2-methyl-5-nitrobenzene
The title compound, C9H9Cl2NO2, is a natural product isolated from the endophytic fungus No. B77 of the mangrove tree from the South China Sea coast. In the crystal structure, the molecules lie on twofold axes and form offset stacks through face-to-face π–π interactions. Adjacent molecules in each stack are related by a centre of inversion and have an interplanar separation of 3.53 (1) Å, with a centroid–centroid distance of 3.76 (1) Å. Between stacks, there are C—H⋯O interactions to the nitro groups and Cl⋯Cl contacts of 3.462 (1) Å
3-Hydroxymethyl-6,8-dimethoxy-2H-chromen-2-one
The asymmetric unit of the title compound, C12H12O5, contains four independent molecules. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the molecules into one-dimensional infinite chains. They are arranged in a nearly parallel fashion along the b axis and stabilized by π–π interactions [3.443 (2) Å]
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