1,444 research outputs found
Structure of Metastable States in Phase Transitions with High-Spin Low-Spin Degree of Freedom
Difference of degeneracy of the low-spin (LS) and high-spin (HS) states
causes interesting entropy effects on spin-crossover phase transitions and
charge transfer phase transitions in materials composed of the spin-crossover
atoms. Mechanisms of the spin-crossover (SC) phase transitions have been
studied by using Wajnflasz model, where the degeneracy of the spin states (HS
or LS) is taken into account and cooperative natures of the spin-crossover
phase transitions have been well described. Recently, a charge transfer (CT)
phase transition due to electron hopping between LS and HS sites has been
studied by using a generalized Wajnflasz model. In the both systems of SC and
CT, the systems have a high temperature structure (HT) and a low temperature
structure (LT), and the change between them can be a smooth crossover or a
discontinuous first order phase transition depending on the parameters of the
systems. Although apparently the standard SC system and the CT system are very
different, it is shown that both models are equivalent under a certain
transformation of variables. In both systems, the structure of metastable state
at low temperatures is a matter of interest. We study temperature dependence of
fraction of HT systematically in a unified model, and find several structures
of equilibrium and metastable states of the model as functions of system
parameters. In particular, we find a reentrant type metastable branch of HT in
a low temperature region, which would play an important role to study the
photo-irradiated processes of related materials.Comment: 19 pages, 11 figure
Mitochondrial Genome Polymorphism in Lolium perenne
The restriction fragment length polymorphisms (RFLPs) of mitochondrial DNA (mtDNA) of perennial ryegrass (Lolium perenne L.) were investigated to elucidate the genetic relatedness among the 128 cultivars including diploid and tetraploid. Many patterns of RFLPs were observed and allowed assigning of the cultivars into the main eight haplotypes of mitochondrial genome relatedness. The American cultivars were classified into haplotype I and VIII which were remote at the mitochondrial genome from each other, the European ones were distributed to all haplotypes and the tetraploid ones were mostly assigned into the haplotype V. The assessment of mtDNA RFLPs may be a valuable method in analyzing a cytoplasmic differentiation among the perennial ryegrass cultivars. Further investigations are required to elucidate mtDNA diversity in relation with the maternal effects on the agronomic traits of perennial ryegrass
Robust, Conducting, and Transparent Polymer Composites using Surface-Modified and Individualized Double-Walled Carbon Nanotubes
This is the pre-peer reviewed version of the following article: ADVANCED MATERIALS. 20(23):4509-4512 (2008), which has been published in final form at 10.1002/adma.200801659.ArticleADVANCED MATERIALS. 20(23):4509-4512 (2008)journal articl
Raman study on electrochemical lithium insertion into multiwalled carbon nanotubes
This is the pre-peer reviewed version of the following article: JOURNAL OF RAMAN SPECTROSCOPY 39(9): 1183-1188, 2008, which has been published in final form http://www3.interscience.wiley.com/journal/118639317/abstract.ArticleJOURNAL OF RAMAN SPECTROSCOPY. 39(9): 1183-1188 (2008)journal articl
Isolation and molecular characterization of multidrug-resistant Gram-negative bacteria from imported flamingos in Japan
Imported animals, especially those from developing countries, may constitute a potential hazard to native animals and to public health. In this study, a new flock of lesser flamingos imported from Tanzania to Hiroshima Zoological Park were screened for multidrug-resistant Gram-negative bacteria, integrons and antimicrobial resistance genes. Thirty-seven Gram-negative bacterial isolates were obtained from the flamingos. Seven isolates (18.9%) showed multidrug resistance phenotypes, the most common being against: ampicillin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole and nalidixic acid. Molecular analyses identified class 1 and class 2 integrons, β-lactamase-encoding genes, blaTEM-1 and blaCTX-M-2 and the plasmid-mediated quinolone resistance genes, qnrS and qnrB. This study highlights the role of animal importation in the dissemination of multidrug-resistant bacteria, integrons and antimicrobial resistance genes from one country to another
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