398 research outputs found
Comparison of genetic diversity and growth traits among Fangzheng silver crucian carp (Carassius auratus gibelio) gynogenetic clones
The silver crucian carp (Carassius auratus gibelio), a gynogenetic teleost, is a promising model for the study of evolutionary genetics in vertebrates. We identified ten gynogenetic clones (FZ-I~FZ-X) from triploid silver crucian carp, collected from Fangzheng County in Heilongjiang Province, China, using microsatellite markers. The genetic diversity of these gynogenetic clones was analyzed using 52 microsatellite markers. A total of 413 alleles were detected and the length of fragments ranged from 96 to 340 bp. The number of alleles per locus varied from 2~19 (mean=7.9423). The observed heterozygosity at polymorphic loci ranged from 0.10~1.00 (mean=0.80). The average allele count per gynogenetic clone ranged from 1.9423~2.1923. The ratio of the polymorphic locus was from 71.15% (VII) to 84.61% (IX) per clone. The number of genotypes ranged from 2~10 per locus. Ten genotypes were observed by analyzing each of 14 microsatellites. As a result, each gynogenetic clone could be accurately identified. In addition, the growth traits, including body weight, length, and height, among five gynogenetic clones were compared. There was a significant difference among gynogenetic clones. Clone FZ-V exhibited the best growth traits, with the largest body weight (53.17±5.24 g), length (11.38±0.37 cm) and height (4.69±0.18 cm). Our results provide basic data for the identification of silver crucian carp gynogenetic clones and can be used as a guide genetic breeding programs
Solution-processable single-material molecular emitters for organic light-emitting devices
This tutorial review presents some recent developments in the design, synthesis and implementation of organic solution-processable molecular fluorophores for non-doped electroluminescent light-emitting devices. After a brief presentation of the basic principles of operation and main characteristics of electroluminescent devices, some examples of active emitters representative of the main classes of non-doped molecular electrofluorophores will be discussed. Emphasis is placed on the relationships between the molecular structure and the electronic properties of molecular emitters, in which high photoluminescence efficiency, synthetic accessibility and processability are combined by design with additional functions such as hole and/or electron injection and transport
Properties and Performance of Two Wide Field of View Cherenkov/Fluorescence Telescope Array Prototypes
A wide field of view Cherenkov/fluorescence telescope array is one of the
main components of the Large High Altitude Air Shower Observatory project. To
serve as Cherenkov and fluorescence detectors, a flexible and mobile design is
adopted for easy reconfiguring of the telescope array. Two prototype telescopes
have been constructed and successfully run at the site of the ARGO-YBJ
experiment in Tibet. The features and performance of the telescopes are
presented
Structure-properties relationships in solution-processable single-material molecular emitters for efficient green organic light-emitting diodes
The electroluminescent properties of a series of solution-processable fluorescent molecular emitters have been systematically investigated. While the introduction of the electron-deficient benzothiadiazole unit in the structure confers efficient electron-injection on the emitter materials, they exhibit different hole-transport properties. The device characteristics of the OLEDs based on these various emitters are discussed on the basis of (i) the energy levels of their HOMO and LUMO and (ii) their hole-transport properties in relation with the charge-transport and blocking properties of the electron- and hole-transport layers. (C) 2012 Elsevier B.V. All rights reserved
A Dithienylbenzothiadiazole Pure Red Molecular Emitter with Electron Transport and Exciton Self-Confinement for Nondoped Organic Red-Light-Emitting Diodes
An amorphous photoluminescent material based on a dithienylbenzothiadiazole structure has been used for the fabrication of organic red-light-emitting diodes. The synergistic effects of the electron-transport ability and exciton confinement of the emitting material allow for the fabrication of efficient pure-red-light-emitting devices without a hole blocker
The Superconductivity, Intragrain Penetration Depth and Meissner Effect of RuSr2(Gd,Ce)2Cu2O10+delta
The hole concentration (p)(delta), the transition temperature Tc, the
intragrain penetration depth lambda, and the Meissner effect were measured for
annealed RuSr2(Gd,Ce)2Cu2O10+delta samples. The intragrain superconducting
transition temperature Tc} varied from 17 to 40 K while the p changed by only
0.03 holes/CuO2. The intragrain superfluid-density 1/lambda^2 and the
diamagnetic drop of the field-cooled magnetization across Tc (the Meissner
effect), however, increased more than 10 times. All of these findings are in
disagreement with both the Tc vs. p and the Tc vs. 1/lambda^2 correlations
proposed for homogeneous cuprates, but are in line with a possible
phase-separation and the granularity associated with it.Comment: 7 pages, 6 figures, accepted for publication in Phys. Rev. B (May 2,
2002
Muon-spin rotation and magnetization studies of chemical and hydrostatic pressure effects in EuFe_{2}(As_{1-x}P_{x})_{2}
The magnetic phase diagram of EuFe(AsP) was
investigated by means of magnetization and muon-spin rotation studies as a
function of chemical (isovalent substitution of As by P) and hydrostatic
pressure. The magnetic phase diagrams of the magnetic ordering of the Eu and Fe
spins with respect to P content and hydrostatic pressure are determined and
discussed. The present investigations reveal that the magnetic coupling between
the Eu and the Fe sublattices strongly depends on chemical and hydrostatic
pressure. It is found that chemical and hydrostatic pressure have a similar
effect on the Eu and Fe magnetic order.Comment: 11 pages, 10 figure
Semileptonic decays and Charmonium distribution amplitude
In this paper we study the semileptonic decays of the meson in the
Light-Cone Sum Rule (LCSR) approach. The result for each channel depends on the
corresponding distribution amplitude of the final meson. For the case of
decaying into a pseudoscalar meson, to twist-3 accuracy only the leading twist
distribution amplitude (DA) is involved if we start from a chiral current. If
we choose a suitable chiral current in the vector meson case, the main twist-3
contributions are also eliminated and we can consider the leading twist
contribution only. The leading twist distribution amplitudes of the charmonium
and other heavy mesons are given by a model approach in the reasonable way.
Employing this charmonium distribution amplitude we find the cross section
which is consistent with Belle
and BaBar's data. Based on this model, we calculate the form factors for
various decay modes in the corresponding regions. Extrapolating the form
factors to the whole kinetic regions, we get the decay widths and branching
ratios for various decay modes including their modes when they are
kinematically accessible.Comment: Changed content partially, Added references, 16 pages,2 figure
Asymmetrically 9,10-disubstituted anthracenes as soluble and stable blue electroluminescent molecular glasses
Asymmetrically 9,10-disubstituted anthracene derivatives 1a/1b have been synthesized and characterized. The new compounds exhibit a high solubility and can be easily purified by chromatographic methods. Thin solid films based on these compounds combine intrinsic amorphous morphology with pure blue emission and high solid-state photoluminescent efficiencies. These materials have been used as solution-processed active emitters in electroluminescent devices leading to interesting device performances. The effect of partial fluorination of a sub-unit of one of the compounds on the properties of the material is discussed
An Ionic Molecular Glass as Electron Injection Layer for Efficient Polymer Light-Emitting Diode
An ionic molecular glass based on a dendronized monoammonium salt has been facilely synthesized and utilized as an interfacial electron-injection layer in a light-emitting diode (LED). The characterization of a yellow-green LED that involves an Al cathode and a thin layer of the new compound spin cast from a methanol solution has shown device performances comparable to those obtained with a Ba/Al cathode. Photovoltaic measurements under white light irradiation reveal that a thin layer of the new compound can significantly increase the built-in potential and thus facilitate electron injection from an Al cathode. Furthermore, it is interesting to observe that the new ionic salt could undergo reorganization on the emissive conjugated polymer layer, which leads to the formation of nearly uniform nanoaggregates
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