Atom-molecule conversion with particle losses

Based on the mean-field approximation and the phase space analysis, we study the dynamics of an atom-molecule conversion system subject to particle loss. Starting from the many-body dynamics described by a master equation, an effective nonlinear Schr\"odinger equation is introduced. The classical phase space is then specified and classified by fixed points. The boundary, which separate different dynamical regimes have been calculated and discussed. The effect of particle loss on the conversion efficiency and the self-trapping is explored.Comment: 6 pages, 5 figure

Entropy and specific heat for open systems in steady states

The fundamental assumption of statistical mechanics is that the system is equally likely in any of the accessible microstates. Based on this assumption, the Boltzmann distribution is derived and the full theory of statistical thermodynamics can be built. In this paper, we show that the Boltzmann distribution in general can not describe the steady state of open system. Based on the effective Hamiltonian approach, we calculate the specific heat, the free energy and the entropy for an open system in steady states. Examples are illustrated and discussed.Comment: 4 pages, 7 figure

VOFilter, Bridging Virtual Observatory and Industrial Office Applications

VOFilter is an XML based filter developed by the Chinese Virtual Observatory project to transform tabular data files from VOTable format into OpenDocument format. VOTable is an XML format defined for the exchange of tabular data in the context of the Virtual Observatory (VO). It is the first Proposed Recommendation defined by International Virtual Observatory Alliance, and has obtained wide support from both the VO community and many Astronomy projects. OpenOffice.org is a mature, open source, front office applications suite with the advantage of native support of industrial standard OpenDocument XML file format. Using the VOFilter, VOTable files can be loaded in OpenOffice.org Calc, a spreadsheet application, and then displayed and analyzed as other spreadsheet files. Here, the VOFilter acts as a connector, bridging the coming VO with current industrial office applications. Virtual Observatory and technical background of the VOFilter are introduced. Its workflow, installation and usage are presented. Existing problems and limitations are also discussed together with the future development plans.Comment: Accepted for publication in ChJAA (9 pages, 2 figures, 185KB

Structural and electronic properties of SrZrO3 and Sr(Ti,Zr) O3 alloys

Using hybrid density functional calculations, we study the electronic and structural properties of SrZrO3 and ordered Sr(Ti,Zr)O3 alloys. Calculations were performed for the ground-state orthorhombic (Pnma) and high-temperature cubic (Pm3m) phases of SrZrO3. The variation of the lattice parameters and band gaps with Ti addition was studied using ordered SrTixZr1-xO3 structures with x=0, 0.25, 0.5, 0.75, and 1. As Ti is added to SrZrO3, the lattice parameter is reduced and closely follows Vegard's law. On the other hand, the band gap shows a large bowing and is highly sensitive to the Ti distribution. For x=0.5, we find that arranging the Ti and Zr atoms into a 1×1SrZrO3/SrTiO3 superlattice along the [001] direction leads to interesting properties, including a highly dispersive single band at the conduction-band minimum (CBM), which is absent in both parent compounds, and a band gap close to that of pure SrTiO3. These features are explained by the splitting of the lowest three conduction-band states due to the reduced symmetry of the superlattice, lowering the band originating from the in-plane Ti 3dxy orbitals. The lifting of the t2g orbital degeneracy around the CBM suppresses scattering due to electron-phonon interactions. Our results demonstrate how short-period SrZrO3/SrTiO3 superlattices could be exploited to engineer the band structure and improve carrier mobility compared to bulk SrTiO3

Management reference for nature reserve networks based on MaxEnt modeling and gap analysis: a case study of the brown–eared pheasant in China

Referencia para la gestión de las redes de reservas naturales basada en la creación de modelos MaxEnt y el análisis de deficiencias: un estudio del faisán orejudo pardo en China La planificación de reservas naturales y la creación de redes son importantes para la conservación de los hábitats y la fauna silvestre. Los análisis de las deficiencias son instrumentos eficientes y fiables para establecer un orden de prioridad entre las iniciativas de conservación de hábitats, en especial por lo que respecta a las especies en peligro de extinción. Proponemos un plan de conservación para el faisán orejudo pardo, Crossoptilon mantchuricum, mediante la determinación de las zonas con una protección insuficiente en las 14  reservas naturales existentes. En total, se seleccionaron 45  localidades y 11  variables ambientales en función de las características del uso del hábitat del faisán orejudo pardo, y se utilizó un modelo de máxima entropía (MaxEnt) para obtener la distribución de la especie. Los resultados del modelo MaxEnt mostraron una elevada precisión de predicción. Los resultados del análisis de las deficiencias revelaron que en las montañas Luliang, en Shanxi, y las montañasXiaowutai, en Hebei, la protección era insuficiente. Encontramos 458  km2 de hábitat óptimo y 1.390  km2 de hábitat moderadamente adecuado dentro de los límites de la reserva natural nacional. No obstante, casi 1.861  km2 del hábitat óptimo y 17.035  km2 del hábitat moderadamente adecuado no estaban protegidos, lo que equivale al 9,0% y el 82,1%, respectivamente, del hábitat adecuado total. La mayor parte de la superficie sin protección estaba formada por hábitat moderadamente adecuado para el faisán orejudo pardo y debería considerarse prioritaria en las iniciativas futuras de conservación. Hay nueve reservas naturales a lo largo de un eje norte–sur en las montañas Luliang que forma un pasillo ecológico. Para mantener la integridad, originalidad y continuidad de estos hábitats y, por tanto, proteger el faisán orejudo pardo, deberían reforzarse los departamentos locales de conservación con miras a mejorar la gestión de la reserva natural a escala provincial y poner en práctica eficazmente las iniciativas de conservación.Referencia para la gestión de las redes de reservas naturales basada en la creación de modelos MaxEnt y el análisis de deficiencias: un estudio del faisán orejudo pardo en China La planificación de reservas naturales y la creación de redes son importantes para la conservación de los hábitats y la fauna silvestre. Los análisis de las deficiencias son instrumentos eficientes y fiables para establecer un orden de prioridad entre las iniciativas de conservación de hábitats, en especial por lo que respecta a las especies en peligro de extinción. Proponemos un plan de conservación para el faisán orejudo pardo, Crossoptilon mantchuricum, mediante la determinación de las zonas con una protección insuficiente en las 14  reservas naturales existentes. En total, se seleccionaron 45  localidades y 11  variables ambientales en función de las características del uso del hábitat del faisán orejudo pardo, y se utilizó un modelo de máxima entropía (MaxEnt) para obtener la distribución de la especie. Los resultados del modelo MaxEnt mostraron una elevada precisión de predicción. Los resultados del análisis de las deficiencias revelaron que en las montañas Luliang, en Shanxi, y las montañasXiaowutai, en Hebei, la protección era insuficiente. Encontramos 458  km2 de hábitat óptimo y 1.390  km2 de hábitat moderadamente adecuado dentro de los límites de la reserva natural nacional. No obstante, casi 1.861  km2 del hábitat óptimo y 17.035  km2 del hábitat moderadamente adecuado no estaban protegidos, lo que equivale al 9,0% y el 82,1%, respectivamente, del hábitat adecuado total. La mayor parte de la superficie sin protección estaba formada por hábitat moderadamente adecuado para el faisán orejudo pardo y debería considerarse prioritaria en las iniciativas futuras de conservación. Hay nueve reservas naturales a lo largo de un eje norte–sur en las montañas Luliang que forma un pasillo ecológico. Para mantener la integridad, originalidad y continuidad de estos hábitats y, por tanto, proteger el faisán orejudo pardo, deberían reforzarse los departamentos locales de conservación con miras a mejorar la gestión de la reserva natural a escala provincial y poner en práctica eficazmente las iniciativas de conservación.Nature reserve designs and networks are important for wildlife and habitat conservation. Gap analyses are efficient and reliable tools for prioritizing habitat conservation efforts, especially when considering endangered species. We propose a conservation plan for the brown–eared pheasant, Crossoptilon mantchuricum, by identifying protection gap areas based on 14 existing nature reserves. A total of 45 locality sites and 11 environmental variables were selected according to the characteristics of habitat use of the brown–eared pheasant and applied to a maximum entropy (MaxEnt) model to obtain the species distribution. The MaxEnt model results showed a high prediction accuracy. The gap analysis results revealed that the Luliang Mountains in Shanxi and the Xiaowutai Mountains in Hebei had protection gaps. We found 458 km2 of optimum habitat and 1,390 km2 of moderately suitable habitat within the national nature reserve range. However, almost 1,861 km2 of the optimum habitat and 17,035 km2 of the moderately suitable habitat were unprotected, equivalent to 9.0% and 82.1%, respectively, of the total suitable habitat. Most of the unprotected area comprised moderately suitable habitat for brown–eared pheasant and should be prioritized in future conservation efforts. There are nine nature reserves along a north–to–south range in the Luliang Mountains that form a wildlife habitat corridor. To maintain the integrity, originality, and continuity of these habitats and thus protect brown–eared pheasants, local conservation departments should be strengthened to improve provincial nature reserve management and successfully carry out conservation efforts

Effect of inter-subsystem couplings on the evolution of composite systems

The effect of inter-subsystem coupling on the adiabaticity of composite systems and that of its subsystems is investigated. Similar to the adiabatic evolution defined for pure states, non-transitional evolution for mixed states is introduced; conditions for the non-transitional evolution are derived and discussed. An example that describes two coupled qubits is presented to detail the general presentation. The effects due to non-adiabatic evolution on the geometric phase are also presented and discussed.Comment: 5 pages, 1 figur

Depolarization regions of nonzero volume in bianisotropic homogenized composites

In conventional approaches to the homogenization of random particulate composites, the component phase particles are often treated mathematically as vanishingly small, point-like entities. The electromagnetic responses of these component phase particles are provided by depolarization dyadics which derive from the singularity of the corresponding dyadic Green functions. Through neglecting the spatial extent of the depolarization region, important information may be lost, particularly relating to coherent scattering losses. We present an extension to the strong-property-fluctuation theory in which depolarization regions of nonzero volume and ellipsoidal geometry are accommodated. Therein, both the size and spatial distribution of the component phase particles are taken into account. The analysis is developed within the most general linear setting of bianisotropic homogenized composite mediums (HCMs). Numerical studies of the constitutive parameters are presented for representative examples of HCM; both Lorentz-reciprocal and Lorentz-nonreciprocal HCMs are considered. These studies reveal that estimates of the HCM constitutive parameters in relation to volume fraction, particle eccentricity, particle orientation and correlation length are all significantly influenced by the size of the component phase particles