Descriptor and scaling relations for ion mobility in battery electrodes and solid electrolytes

Based on first-principles electronic structure calculations, we have derived an efficient physical descriptor for the ion mobility in battery electrodes and solid electrolytes which is a critical performance parameter in electrochemical energy storage and conversion. This descriptor is entirely composed of observables that are easily accessible: ionic radii, oxidation states and the difference in the Pauling electronegativities of the involved species. Within a particular class of materials, the activation barriers for migration are connected to this migration parameter through linear scaling relations both as far as the variation of the cation chemistry of the charge carriers and the anion chemistry of the host lattice are concerned. The validity of these scaling relations indicates that a purely ionic view of ion mobility in solids falls short of capturing all factors influencing this mobility. The identification of these scaling relations has the potential to significantly accelerate the discovery of materials with desired mobility properties.

Clustered Exact Daum-Huang Particle Flow Filter

Unlike the conventional particle filters, particle flow filters do not rely on proposal density and importance sampling; they employ flow of the particles through a methodology derived from the log-homotopy scheme and ensure successful migration of the particles. Amongst the efficient implementations of particle filters, Exact Daum-Huang (EDH) filter pursues the calculation of migration parameters all together. An improved version of it, Localized Exact Daum-Huang (LEDH) filter, calculates the migration parameters separately. In this study, the main objective is to reduce the cost of calculation in LEDH filters which is due to exhaustive calculation of each migration parameter. We proposed the Clustered Exact Daum-Huang (CEDH) filter. The main impact of CEDH is the clustering of the particles considering the ones producing similar errors and then calculating the same migration parameters for the particles within each cluster. Through clustering and handling the particles with high errors, their engagement and influence can be balanced, and the system can greatly reduce the negative effects of such particles on the overall system. We implement the filter successfully for the scenario of high dimensional target tracking. The results are compared to those obtained with EDH and LEDH filters to validate its efficiency.

Post-data inference of coalescence times and segregating-site distribution in a two-island model with symmetric migration

In this paper, we present the distribution of the coalescence time of two DNA sequences (or genes) subject to symmetric migration between two islands, and conditional on the observed number of segregating sites in the sequences. The distribution for the segregating-site pattern is also obtained. Some surprising results emerge when both genes are initially on the same island. First, the post-data mean coalescence time is shown to be dependent on the migration parameter, as opposed to the pre-data mean. Second, both the post-data density and expectation for the coalescence time are shown to converge, in the weak-migration limit, to the corresponding panmictic results, as opposed to the pre-data situation where there is convergence in the density but not in the expectation. Finally, it is shown that there is convergence in the weak-migration limit in the distribution of the number of segregating sites but not in the expectation and variance. Numerical and graphical results for samples of size greater than two are also presented.

Post-data inference of coalescence times and segregating-site distribution in a two-island model with symmetric migration

In this paper, we present the distribution of the coalescence time of two DNA sequences (or genes) subject to symmetric migration between two islands, and conditional on the observed number of segregating sites in the sequences. The distribution for the segregating-site pattern is also obtained. Some surprising results emerge when both genes are initially on the same island. First, the post-data mean coalescence time is shown to be dependent on the migration parameter, as opposed to the pre-data mean. Second, both the post-data density and expectation for the coalescence time are shown to converge, in the weak-migration limit, to the corresponding panmictic results, as opposed to the pre-data situation where there is convergence in the density but not in the expectation. Finally, it is shown that there is convergence in the weak-migration limit in the distribution of the number of segregating sites but not in the expectation and variance. Numerical and graphical results for samples of size greater than two are also presented.

Molecular Population Genetics of X-Linked Genes in Drosophila pseudoobscura

This article presents a nucleotide sequence analysis of 500 bp determined in each of five X-linked genes, runt, sisterlessA, period, esterase 5, and Heat-shock protein 83, in 40 Drosophila pseudoobscura strains collected from two populations. Estimates of the neutral migration parameter for the five loci show that gene flow among D. pseudoobscura populations is sufficient to homogenize inversion frequencies across the range of the species. Nucleotide diversity at each locus fails to reject a neutral model of molecular evolution. The sample of 40 chromosomes included six Sex-ratio inversions, a series of three nonoverlapping inversions that are associated with a strong meiotic drive phenotype. The selection driven by the Sex-ratio meiotic drive element has not fixed variation across the X chromosome of D. pseudoobscura because, while significant linkage disequilibrium was observed within the sisterlessA, period, and esterase 5 genes, we did not find evidence for nonrandom association among loci. The Sex-ratio chromosome was estimated to be 25,000 years old based on the decomposition of linkage disequilibrium between esterase 5 and Heat-shock protein 83 or 1 million years old based on the net divergence of esterase 5 between Standard and Sex-ratio chromosomes. Genetic diversity was depressed within esterase 5 within Sex-ratio chromosomes, while the four other genes failed to show a reduction in heterozygosity in the Sex-ratio background. The reduced heterogeneity in esterase 5 is due either to its location near one of the Sex-ratio inversion breakpoints or that it is closely linked to a gene or genes responsible for the Sex-ratio meiotic drive system.

A GEOCHEMICAL INVESTIGATION OF OILS AND SOURCE ROCKS FROM THE SURAT BASIN

A series of twelve oils and five source rocks and potential source rocks from the Surat Basin have been subjected to detailed geochemical analyses. Particular attention has been given to determining the distribution of various classes of biomarkers such as the steranes and triterpanes. The results from this study have shown that the Cabawin oil is derived from the Permian Back Creek Formation and has a high content of marine organic source material. The Triassic/Jurassic oils have a different source from the Cabawin oil and are dominated by land plant source material. Within the Triassic/Jurassic oils there are subtle variations in biomarker distributions suggesting that some oils may have small but additional amounts of different source materials. A number of Cretaceous and Jurassic potential source rocks (i.e. Walloon) have biomarker parameters clearly indicating levels of maturity at which oil generation is impossible.A number of the oils in this basin are extensively biodegraded. In particular biodegradation has been very heavy in the Riverslea/Yapunyah area. With the exception of Conloi oil, all the oils appear to have been exposed to similar levels of maturity. A biomarker migration parameter has provided some tentative evidence to suggest that, in general, oils in the southern part of the basin have migrated further than those in the northern part.In summary, the biomarker data from oils and source rocks of the Surat Basin have been used to provide a new insight into the origin of the Surat Basin oils and their post-formation history.

A Modified Approach to the Study of Blended Yarn Structures

The paper describes a method by which two different but important aspects of blended yarn structures could be studied together by a common procedure and set of parameters. These two aspects are: fiber helix migration, the importance of the study of which has been generally overlooked in blended yarns, and preferential radial migration. The present work is largely a theoretical attempt to relate a fiber helix migration parameter, the mean fiber position [Formula: see text], with a preferential radial migration parameter, the linear migration index V. The latter is a new parameter that is introduced in this paper, and although quite similar to Hamilton's migration index M in its general properties, it characterizes the preferential radial migration on a linear scale and bears, under uniform packing conditions, an exact and a simple relationship with [Formula: see text]. An appendix included at the end gives the treatment relating [Formula: see text]with M. The results of a small experiment carried out on a binary blend, 50/50 by weight of 3- and 6-denier, 21/2-in. staple, Kodel® polyester fibers, are also described. These provided a limited but useful means of checking the theoretical relations.