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Chinese Physics C 2008年第6期32卷 455-462页

作者： S.l.Olsen Institute of High Energy Physics Chinese Academy of Sciences

I review some of the recent experimental results on the so-called XYZ mesons.

关键词： charmonium multiquark mesons quark-gluon hybrids

Azo Dye Doped Polymer Films for Nonlinear Optical Applications

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Chinese Journal of Polymer Science 2014年第5期32卷 650-657页

作者： l.Guru Prasad Department of Science & Humanities M.Kumarasamy College of Engineering

Azo dye doped polymer films were prepared on glass substrates using spin-coating technique. FTIR, UV-Vis spectra and Pl measurements were recorded to characterize the structure of the metanil yellow doped PVA films. Surface morphology and thickness of the films were studied using AFM and FESEM. The magnitude of both real and imaginary parts of third-order nonlinear susceptibility χ3 of metanil yellow were determined by the Z-scan technique. The nonlinear refractive index n2 and the nonlinear absorption coefficient β of the azo dye doped polymer films were calculated respectively. The real part of the third-order susceptibility χ3 is much larger than its imaginary part indicating that the third-order optical response of the metanil yellow doped PVA films is dominated by the optical nonlinear refractive behavior.

关键词： Azo dye PVA Nonlinear optical materials.

Detailed Analysis of Quantum Phase Transitions Within the u(2) Algebra

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Communications in Theoretical Physics 2010年第10期54卷 589-593页

作者： l.Fortunato l.Sartori Dipartimento di Fisica“G.Galilei”and INFN the ECT Europen Center for Theoretical Nuclear Physics CISAS G.Colombo

We analyze in detail the quantum phase transitions that arise in models based on the u(2) algebraicdescription for bosonic systems with two types of scalar *** we discuss the quantum phase transition thatoccurs in hamiltonians that admix the two dynamical symmetry chains u(2)  u(1) and u(2)  so(2) by diagonalizingthe problem exactly in the u(1) *** we apply the coherent state formalism to determine the energy *** we show that a quantum phase transition of a different nature, but displaying similar characteristics, may arisealso within a single chain just by including higher order terms in the hamiltonian.

关键词： algebraic models lie algebra quantum phase transitions lipkin model

How will biomining be applied in future?

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中国有色金属学会会刊：英文版 2008年第6期18卷 1302-1310页

作者： C.l.BRIERlEY Brierley Consultancy llC P.O.Box 630012Highlands Ranch

这篇论文在全世界考察商业 biomining 操作的当前的地位，识别作为一种处理技术驾驶 biomining 的选择的因素，描述挑战到利用这些革新，并且与 biomining 的未来的讨论得出结论。Biomining 商业地用设计垃圾场，堆和搅动的坦克被使用... 详细信息

这篇论文在全世界考察商业 biomining 操作的当前的地位，识别作为一种处理技术驾驶 biomining 的选择的因素，描述挑战到利用这些革新，并且与 biomining 的未来的讨论得出结论。Biomining 商业地用设计垃圾场，堆和搅动的坦克被使用。克服阴沉的费用的技术挑战，处理在矿的低档，低质量、复杂的矿石和利用存在大写的投资要求微生物引起的活动和创新工程的更好的理解。克服 biomining 广告挑战必要改进采矿 company/biomining 改革者合作和知识产权控制。

关键词：生物采矿生物浸取应用技术研究

Energy and momentum of rotating frames in tetrad gravity

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Chinese Physics B 2011年第10期20卷 101-111页

作者： Gamal G l Nashed Mathematics Department Faculty of Science Ain Shams University

Within the framework of the tetrad formulation of general relativity theory, we compute the total energy and momentum of four rotating frames using the gravitational energy-momentum 3-form. We show how the effect of inertia always makes the total energy divergent. We use a natural regularization method to obtain physical values for the total energy of the system and show how it works on a number of explicit examples. We also show by calculation that inertia has no effect on the momentum components.

关键词： teleparallel gravity, energy-momentum WeitzenbSck connection, regularization telepar-allelism

Nanoscale 3D ordered polymer networks

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Science China Chemistry 2018年第1期61卷 25-32页

作者： Edwin l. Thomas Department of Materials Science and NanoEngineering Rice University Houston TX 77030 USA

Structures having nanoscale 3D geometries are valuable as multifunctional materials, where multi-continuous microphases can synergistically influence mechanical, optical, transport and other properties. Such very high interface surface to volume ratio structures occur in a variety of materials including natural materials such as butter fly wings and sea urchin exoskeletons and in synthetic self-assembled structures such as surfactant/water systems and block polymers. Quantitative morphological characterization of such complex geometric structures is quite challenging. Unit cell sizes range from 10-300 nm with corresponding feature sizes on the 2-50 nm scale. Since these nanoscale network structures are bicontinuous, when one constituent is removed, the structure is still self supporting. Removal of one component produces a nanoporous material that may be in-filled with another component, or the surfaces of the nanopores can be coated with ultra-thin layers by atomic layer deposition to offer multiftmctional capabilities. Due to the ability to individually tailor the properties of the network（s） and matrix, for example, to create strong dielectric or impedance contrast, such spatially periodic structures are excellent for the interference of waves （electromagnetic for photonic applications and acoustic for phononic applications） that can lead to bandgaps and hence the control of wave propagation in the material. This mini-review will focus on networks formed by bottom up self assembly of block polymers. In addition to structural issues, we emphasize the special physical properties related to bi- or tri-continuous networks.

关键词： self assembly block polymer network morphologies bicontinuous

TOPOlOGY AND CASCADING lINE OUTAGES IN POWER GRIDS

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Journal of Systems Science and Systems Engineering 2007年第2期16卷 202-221页

作者： David l. PEPYNE University of Massachusetts Amherst MA USA

Motivated by the small world network research of Watts ＆ Strogatz, this paper studies relationships between topology and cascading line outages in electric power grids. Cascading line outages are a type of cascading collapse that can occur in power grids when the transmission network is congested. It is characterized by a self-sustaining sequence of line outages followed by grid breakup, which generally leads to widespread blackout. The main findings of this work are twofold： On one hand, the work suggests that topologies with more disorder in their interconnection topology tend to be robust with respect to cascading line outages in the sense of being able to support greater generation and demand levels than more regularly interconnected topologies. On the other hand, the work suggests that topologies with more disorder tend to be more fragile in that should a cascade get started, they tend to break apart after fewer outages than more regularly interconnected topologies. Thus, as has been observed in other complex networks, there appears to be a tradeoff between robustness and fragility. These results were established using synthetically generated power grid topologies and verified using the IEEE 57 bus and 188 bus power grid test cases.

关键词： Power grid blackout cascading line failure complex networks robust yet fragile

Effect of particle size distribution on particle based composite anode models

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Acta Mechanica Sinica 2013年第3期29卷 357-369页

作者： Vaughan l.Thomas 148. 3400 Charles Street 031 Latrobe Hall Baltimore Maryland 21218 USA

Particle based models of composite anodes are useful tools for exploring the behavior of SOFC systems. As part of our efforts to develop models for understanding fuel cells, we have been building models of Ni-YSZ composite anodes using experimentally measured particle size distributions. The objectives of this study were to characterize the percolation threshold and conductivity of these models in comparison to simpler mono dispersed and biphasic particle size distributions from the literature. We found that the average values for the onset of percolation and the measured conductivity of the models with experimentally measured particle size distributions are similar to those for the simple distributions and the experimentally measured distributions. For all of the configurations evaluated, the onset of percolation in the Nickel phase occurred at a solid fraction of Nickel between 20% and 25%. This corresponded almost exactly to the point at which the coordination number between Nickel phase particles reached 2.2. The significant finding was that the variation in the value for the conductivity, as measured by the standard deviation of the results, was several orders of magnitude higher than for the simpler systems. We explored the validity of our assumptions, specifically the assumption of random particle placement, by building a particle model directly from FIB-SEM data. In this reconstruction, it was clear that the location of particles was not random. Particles of the same type and size had much likelihood of contact higher than would indicated by random location.

关键词： Resistor network Composite electrodes 3D particle packing Solid oxide fuel cells

Resolving place names in Amdo and Kham:A gazetteer for the Hengduan Mountains region of Southwest China

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植物分类学报 2006年第6期44卷 721-732页

作者： Susan l. KEllEY Arnold Arboretum and Harvard University Herbaria 22 Divinity Avenue Cambridge MA 02138-2020 U.S.A.

Perhaps no region on earth presents such a confusing array of place names as does the area made up of the former provinces of Kham and Amdo in historic Tibet (Xizang). Within these areas, cities, towns, villages, mountains, lakes and other geographic features have at least two names applied to them, one Tibetan, the other Chinese. Overlying this indigenous nomenclature are the names applied by outsiders, mostly Europeans, each of whom used their native language to transliterate the names they heard or read from Tibetan or Chinese script, and names in the languages of other ethnic minorities who live within the area. Adding to the confusion are the conflicting “standards” for transliterating Tibetan and Chinese names. To resolve the inconsistencies and uncertainties of place names in this region, a multilingual gazetteer and thesaurus was prepared. The gazetteer-thesaurus was compiled to be used as a tool for correlating the often radically different names assigned to a single place or feature and to provide the geographic coordinates for each. The impetus for this project was the need to assign geographic coordinates to plant specimens collected in the area since the latter part of the 19th century up until the advent and widespread use of Global Positioning System (GPS) receivers in the 1990s. Georeferencing specimens is necessary for plotting the historical distribution of species and for more completely understanding the information contained on specimen labels. Knowing the distribution of plants is important for answering phylogenetic questions, determining local and widespread biogeographical patterns, identifying areas of unusually high diversity or endemism, and determining areas in need of special protection. The value of such a gazetteer, however, extends well beyond the field of botany. It is intended to be of use to anyone with a desire to know the nomenclatural history of places in the area and for pinpointing with a fair degree of accuracy the location

关键词： Tibet (Xizang) Amdo Kham Hengduan Mountains gazetteer biodiversity Geographic Information Systems (GIS) herbarium conservation georeferencing.

Novel Heat Transfer Issues Associated with the Design and Safe Operation of the MEGAPIE Spallation Source Target

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Journal of Thermal Science 2007年第1期16卷 63-78页

作者： Brian l.Smith Thermal Hydraulics laboratory Paul Scherrer InstituteSwitzerland

Critical heat transfer problems are discussed in the context of the operation of a spallation source target, which represents a first demonstration of the feasibility of an innovative concept for generating energy using a particle accelerator. Within the framework of the umbrella project MEGAPIE, an R＆D support group was organized to take responsibility for target cooling. This involved the use of advanced numerical methods - Computational Fluid Dynamics （CFD） and Finite Element Method （FEM） - validated against suitable experimental data, and by means of appropriate benchmarking exercises. The design studies using CFD resulted in an optimum flow configuration being defined for the coolant circulation. Flow visualization tests were undertaken using a glass/water test section, with the velocity field mapped using optical and ultrasonic measuring techniques. These were followed by heat transfer tests, using the actual target materials （lead-bismuth-eutectic coolant and steel confinement）. Further CFD/FEM work to analyze operational transients and accident sequences was also carded out, and is described in the paper.

关键词： computational fluid dynamics finite element method liquid-metal coolant spallation source target