327 research outputs found
Raman scattering investigation across the magnetic and MI transition in rare earth nickelate RNiO3 (R = Sm, Nd) thin films
We report a temperature-dependent Raman scattering investigation of thin film
rare earth nickelates SmNiO3, NdNiO3 and Sm0.60Nd0.40NiO3, which present a
metal-to-insulator (MI) transition at TMI and an antiferromagnetic-paramagnetic
Neel transition at TN. Our results provide evidence that all investigated
samples present a structural phase transition at TMI but the Raman signature
across TMI is significantly different for NdNiO3 (TMI = TN) compared to SmNiO3
and Sm0.60Nd0.40NiO3 (TMI =/ TN). It is namely observed that the
paramagnetic-insulator phase (TN < T < TMI) in SmNiO3 and Sm0.60Nd0.40NiO3 is
characterized by a pronounced softening of one particular phonon band around
420 cm-1. This signature is unusual and points to an important and continuous
change in the distortion of NiO6 octahedra (thus the Ni-O bonding) which
stabilizes upon cooling at the magnetic transition. The observed behaviour
might well be a general feature for all rare earth nickelates with TMI =/ TN
and illustrates intriguing coupling mechanism in the TMI > T > TN regime.Comment: Revised & published versio
SmNiO3/NdNiO3 thin film multilayers
Rare earth nickelates RENiO3 which attract interest due to their sharp
metal-insulator phase transition, are instable in bulk form due to the
necessity of an important oxygen pressure to stabilize Ni in its 3+ state of
oxidation. Here, we report the stabilization of rare earth nickelates in
[(SmNiO3)t/(NdNiO3)t]n thin film multilayers, t being the thickness of layers
alternated n times. Both bilayers and multilayers have been deposited by
Metal-Organic Chemical Vapour Deposition. The multilayer structure and the
presence of the metastable phases SmNiO3 and NdNiO3 are evidenced from by X-ray
and Raman scattering. Electric measurements of a bilayer structure further
support the structural quality of the embedded rare earth nickelate layers.Comment: Appl. Phys. Lett. (2011), accepte
241-AZ Farm Annulus Extent of Condition Baseline Inspection
This report provides the results of the comprehensive annulus visual inspection for tanks 241- AZ-101 and 241-AZ-102 performed in fiscal year 2013. The inspection established a baseline covering about 95 percent of the annulus floor for comparison with future inspections. Any changes in the condition are also included in this document
Expanding the Circuitry of Pluripotency by Selective Isolation of Chromatin-Associated Proteins
Maintenance of pluripotency is regulated by a network of transcription factors coordinated by Oct4, Sox2, and Nanog (OSN), yet a systematic investigation of the composition and dynamics of the OSN protein network specifically on chromatin is still missing. Here we have developed a method combining ChIP with selective isolation of chromatin-associated proteins (SICAP) followed by mass spectrometry to identify chromatin-bound partners of a protein of interest. ChIP-SICAP in mouse embryonic stem cells (ESCs) identified over 400 proteins associating with OSN, including several whose interaction depends on the pluripotent state. Trim24, a previously unrecognized protein in the network, converges with OSN on multiple enhancers and suppresses the expression of developmental genes while activating cell cycle genes. Consistently, Trim24 significantly improved efficiency of cellular reprogramming, demonstrating its direct functionality in establishing pluripotency. Collectively, ChIP-SICAP provides a powerful tool to decode chromatin protein composition, further enhanced by its integrative capacity to perform ChIP-seq
Tank 241-AY-102 Leak Assessment Supporting Documentation: Miscellaneous Reports, Letters, Memoranda, And Data
This report contains reference materials cited in RPP-ASMT -53793, Tank 241-AY-102 Leak Assessment Report, that were obtained from the National Archives Federal Records Repository in Seattle, Washington, or from other sources including the Hanford Site's Integrated Data Management System database (IDMS)
The Mechanical Design Of The Bpm Inter-Tank Section For P-Linac At FAIR
At the planned Proton LINAC at the FAIR facility,four-fold button Beam Position Monitor (BPM) will beinstalled at 14 locations along the 30 m long FAIR p-LINAC. The LINAC comprises of crossbar H-mode (CH)cavity to accelerate a 70 mA proton beam up to 70 MeVat frequency of 325 MHz. At four locations, the BPMswill be an integral part of the inter-tank section betweenthe CCH and CH cavities within an evacuated housing.As the BPM centre is only 48 mm apart from the upstreamcavity boundary, the rf-background at the BPMposition, generated by the cavity must be evaluated. Inthis paper the mechanical design of the BPM for the intertanksection is presented and the rf-noise at the BPMlocation is discussed
The SARAF-LINAC Project for SARAF-PHASE 2
THPF005International audienceSNRC and CEA collaborate to the upgrade of theSARAF accelerator to 5 mA CW 40 MeV deuteron andproton beams (Phase 2). This paper presents the referencedesign of the SARAF-LINAC Project including a fourvane176 MHz RFQ, a MEBT and a superconducting linacmade of four five-meter cryomodules housing 26superconducting HWR cavities and 20 superconductingsolenoids. The first two identical cryomodules house lowbeta(opt = 0.091), 280 mm long (flange to flange), 176MHz HWR cavities, the two identical last cryomoduleshouse high-beta (opt = 0.181), 410 mm long, 176 MHz,HWR cavities. The beam is focused with superconductingsolenoids located between cavities housing steering coils.A BPM is placed upstream each solenoid
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Double-Shell Tank Visual Inspection Changes REsulting from the Tank 241-AY-102 Primary Tank Leak - 14193
As part of the Double-Shell Tank (DST) Integrity Program, remote visual inspections are utilized to perform qualitative in-service inspections of the DSTs in order to provide a general overview of the condition of the tanks. During routine visual inspections of tank 241-AY -1 02 (A Y -1 02) in August 2012, anomalies were identified on the annulus floor which resulted in further evaluations. In October 2012, Washington River Protection Solutions, LLC determined that the primary tank of AY -102 was leaking. Following identification of the tank AY-102 probable leak cause, evaluations considered the adequacy of the existing annulus inspection frequency with respect to the circumstances of the tank AY-1021eak and the advancing age of the DST structures. The evaluations concluded that the interval between annulus inspections should be shortened for all DSTs, and each annulus inspection should cover > 95 percent of annulus floor area, and the portion of the primary tank (i.e., dome, sidewall, lower knuckle, and insulating refractory) that is visible from the annulus inspection risers. In March 2013, enhanced visual inspections were performed for the six oldest tanks: 241-AY-101, 241-AZ-101,241-AZ-102, 241-SY-101, 241-SY-102, and 241-SY-103, and no evidence of leakage from the primary tank were observed. Prior to October 2012, the approach for conducting visual examinations of DSTs was to perform a video examination of each tank's interior and annulus regions approximately every five years (not to exceed seven years between inspections). Also, the annulus inspection only covered about 42 percent of the annulus floor
4DXpress: a database for cross-species expression pattern comparisons
In the major animal model species like mouse, fish or fly, detailed spatial information on gene expression over time can be acquired through whole mount in situ hybridization experiments. In these species, expression patterns of many genes have been studied and data has been integrated into dedicated model organism databases like ZFIN for zebrafish, MEPD for medaka, BDGP for Drosophila or GXD for mouse. However, a central repository that allows users to query and compare gene expression patterns across different species has not yet been established. Therefore, we have integrated expression patterns for zebrafish, Drosophila, medaka and mouse into a central public repository called 4DXpress (expression database in four dimensions). Users can query anatomy ontology-based expression annotations across species and quickly jump from one gene to the orthologues in other species. Genes are linked to public microarray data in ArrayExpress. We have mapped developmental stages between the species to be able to compare developmental time phases. We store the largest collection of gene expression patterns available to date in an individual resource, reflecting 16 505 annotated genes. 4DXpress will be an invaluable tool for developmental as well as for computational biologists interested in gene regulation and evolution. 4DXpress is available at http://ani.embl.de/4DXpress
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