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Modulation of Insulator-Metal Transition Temperature by Visible Light in La7/8Sr1/8MnO3 Thin Film

HU Ling,SUN Yu-Ping,WANG Bo,LUO Xuan,SHENG Zhi-Gao,ZHU Xue-Bin,SONG Wen-Hai,YANG Zhao-Rong,DAI Jian-Ming,

中国物理快报 , 2010,
Abstract:
Orbital polaron lattice formation in lightly doped La1-xSrxMnO3  [PDF]
J. Geck,P. Wochner,S. Kiele,R. Klingeler,P. Reutler,A. Revcolevschi,B. Buechner
Physics , 2005, DOI: 10.1103/PhysRevLett.95.236401
Abstract: By resonant x-ray scattering at the Mn K-edge on La7/8Sr1/8MnO3, we show that an orbital polaron lattice (OPL) develops at the metal-insulator transition of this compound. This orbital reordering explains consistently the unexpected coexistence of ferromagnetic and insulating properties at low temperatures, the quadrupling of the lattice structure parallel to the MnO2-planes, and the observed polarization and azimuthal dependencies. The OPL is a clear manifestation of strong orbital-hole interactions, which play a crucial role for the colossal magnetoresistance effect and the doped manganites in general.
Metallic and insulating interfaces of amorphous SrTiO3-based oxide heterostructures  [PDF]
Yunzhong Chen,Nini Pryds,Josee E. Kleibeuker,Gertjan Koster,Jirong Sun,Eugen Stamate,Baogen Shen,Guus Rijnders,S. Linderoth
Physics , 2012, DOI: 10.1021/nl201821j
Abstract: The conductance confined at the interface of complex oxide heterostructures provides new opportunities to explore nanoelectronic as well as nanoionic devices. Herein we show that metallic interfaces can be realized in SrTiO3-based heterostructures with various insulating overlayers of amorphous LaAlO3, SrTiO3 and yttria-stabilized zirconia films. On the other hand, samples of amorphous La7/8Sr1/8MnO3 films on SrTiO3 substrates remain insulating. The interfacial conductivity results from the formation of oxygen vacancies near the interface, suggesting that the redox reactions on the surface of SrTiO3 substrates play an important role.
ELABORATION OF THE SUPERSTRUCTURE OF THE BULGARIAN HOTEL INDUSTRY
Tanya Dabeva
UTMS Journal of Economics , 2010,
Abstract: The purpose of the paper is to suggest some terms of reference for the elaboration of the superstructure of the Bulgarian hotel industry. The suggestions are based on the analysis of the superstructure at present. Its capacity, main types of accommodation establishments and their distribution by categories and territory are examined. An analysis is made of some resulting indices such as overnight stays and average stay. The main positive, respectively negative features of the superstructure have been analyzed. Concrete terms of reference have been given in order to overcome the problems specified.
Superconducting Superstructure for the TESLA Collider  [PDF]
J. Sekutowicz,M. Ferrario,C. Tang
Physics , 1998, DOI: 10.1103/PhysRevSTAB.2.062001
Abstract: We discuss the new layout of a cavity chain (superstructure) allowing, we hope, significant cost reduction of the RF system of both linacs of the TESLA linear collider. The proposed scheme increases the fill factor and thus makes an effective gradient of an accelerator higher. We present mainly computations we have performed up to now and which encouraged us to order the copper model of the scheme, still keeping in mind that experiments with a beam will be necessary to prove if the proposed solution can be used for the acceleration.
Induction of mammary gland tumor in female Sprague- Dawley rats with LA7 cells
R Abbasalipourkabir, A Dehghan, A Salehzadeh, F Shamsabadi, R Abdullah
African Journal of Biotechnology , 2010,
Abstract: The current methods for tumor induction in breast cancer research animal models are time-consuming, hazardous, expensive, sometimes irreproducible and inconvenient. We successfully developed a new, simple and cost-effective method in developing solid mammary gland tumor in female Sprague-Dawley rat using LA7 rat mammary tumor cells. Tumors developed in 7- 8 weeks old rats within 6 to 8 days of subcutaneous injection of LA7 cells into the mammary gland pad. Tumor size increased exponentially for four weeks. Histopathology examination confirmed that the induced tumors were adenocarcinomas. Evaluation of blood enzymes showed significantly higher (P < 0.005) serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in tumor-bearing than in normal rats. This LA7 cell-induced rat mammary gland tumor model may be useful for studies in breast cancer drug or nutraceutical research and development.
Topological insulators with perfect vacancy superstructure and possible implications for iron chalcogenide superconductors  [PDF]
Xiao-Yong Feng,Hua Chen,Chao Cao,Jianhui Dai
Physics , 2011,
Abstract: Motivated by the newly-discovered intercalated iron chalcogenide superconductors, we construct a single orbital tight-binding model for topological insulators on the square lattice with a perfect vacancy superstructure. We find that such lattice structure naturally accommodates a non-vanishing geometry phase associated with the next-nearest-neighbor spin-orbit interaction. By calculating the bulk band structures and the finite stripe edge states, we show that the topological insulator phases can be tuned at certain electron fillings in a wide range of the model parameters. The possible implications of these results for the iron deficient compounds $(A,Tl)_{y}Fe_{2-x}Se_2$ have been discussed.
Superconducting Superstructure for the TESLA Collider: New Results  [PDF]
N. Baboi,M. Ferrario,M. Liepe,J. Sekutowicz
Physics , 2000,
Abstract: A new cavity-chain layout has been proposed for the main linac of the TESLA linear collider. This superstructure-layout is based upon four 7-cell superconducting standing-wave cavities, coupled by short beam pipes. The main advantages of the superstructure are an increase in the active accelerating length in TESLA and a saving in rf components, especially power couplers, as compared to the present 9-cell cavities. The proposed scheme allows to handle the field-flatness tuning and the HOM damping at sub-unit level, in contrast to standard multi-cell cavities. The superstructure-layout is extensively studied at DESY since 1999. Computations have been performed for the rf properties of the cavity-chain, the bunch-to-bunch energy spread and multibunch dynamics. A copper model of the superstructure has been built in order to compare with the simulations and for testing the field-profile tuning and the HOM damping scheme. A "proof of principle" niobium prototype of the superstructure is now under construction and will be tested with beam at the TESLA Test Facility in 2001. In this paper we present latest results of these investigations.
Rectangular Waveguide HOM Couplers for a TESLA Superstructure  [PDF]
A. Blednykh,D. Kostin,V. Kaljuzhny,M. Lalayan,O. Milovanov,A. Ponomarenko,N. Sobenin,A. Sulimov,D. Trubin,A. Zavadzev,M. Dohlus
Physics , 2000,
Abstract: Some modifications of a Rectangular Waveguide HOM couplers for TESLA superstructure have been investigated. These RWG HOM couplers are to be installed between the cavities of the superstructure and also at the both ends of it. We investigated a RWG HOM coupler attached to the beam pipe through the slots orientated along beam pipe axis (longitudinal slots), perpendicular to it (azimutal slots) and at some angle to this axis. For dipole modes of both polarizations damping two RWG in every design were used. This paper presents the results obtained for scaled-up setup at 3 GHz at room temperature. The advantages of HOM coupler with longitudinal slots for damping dipole modes and compact HOM coupler with slots at some angle to the axis are shown. Arrangement of HOM coupler in cryostat and heating due to HOM and FM losses are presented. Calculations and design of the feeding RWG coupler for superstructure are also presented.
Superstructure Strategy: Do Indonesian EFL Learners Use It?
Evy C Ridwan
TEFLIN Journal , 1997,
Abstract: : This paper reports on a study conducted among Indonesian undergraduate students majoring in English as a Foreign Language (EFL). One strategy that learners generally use to understand the main ideas of an expository text is the superstructure strategy (i.e., utilizing the text structure to understand the main ideas). While research in English as First Language reading has demonstrated the benefit of using this strategy, little do we know whether Indonesian EFL learners use this strategy in reading and whether this strategy is beneficial to them or not. Two versions of an expository text were developed: One version had an explicit text structure, with the inclusion of discourse markers, to elicit learners to use the superstructure strategy; the other was without discourse markers. It was hypothesized that learners who read the version with an explicit text structure would utilize the superstructure strategy thereby comprehending main ideas better than those who read the other version. Additionally, to confirm the hypothesis learners were also asked to answer a questionnaire developed from O'Malley and Chamot (1993) followed by an interview to find out if EFL learners used other strategies to comprehend main ideas.
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