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Conglomerate reservoirs in alluvial fans commonly contain economic crude oil, but it is challenging to depict the distribution of conglomerate reservoirs or to summarise the sedimentary model in alluvial fans deposits owing to their complex lithofacies changes and variable hydrodynamic conditions. This paper focuses on the Poplar River alluvial fan in the northwest Junggar Basin, China, as a special case to analyse its sedimentary processes and to build a sedimentary model through detailed outcrop mapping and grainsize analysis. The Poplar River alluvial fan is a braided river-dominated fan with the characteristics of a large fan size (approximate 327.6 km2), gentle slope (∼<0.04–0.07°), coarse sediments (mainly cobbles or finer pebbles) and rare fine-mud sediments deposited from floods. In this alluvial fan, 15 lithofacies are identified that mainly formed in five hydrodynamic environments: (i) debris-flow deposits; (ii) high-flow traction current deposits; (iii) low-flow traction current deposits; (iv) still-water deposits; and (v) eolian deposits. Moreover, the sedimentary processes on the Poplar River alluvial fan can be divided into flood and interflood periods. During flood periods, sediment deposition plays a major role on the alluvial fan. From the proximal to distal parts, six lithofacies associations can be identified: feeder-channel and sheet-flow deposits in the proximal part, sheet flood and braided-stream deposits in the intermediate part, and channel deposits and wetland deposits in the distal fan areas. During the interflood periods, sediment reworking is the most important function, and three lithofacies associations are identified: main-channel deposits in the proximal fan, braided-trench deposits in the intermediate fan and wetland deposits in the distal area. The braided-stream deposits, braided-trench deposits and sheet-flood deposits have the best potential for high-quality aquifers or oil reservoirs based on their moderately well-sorted grains and high primary permeable intervals. Fifteen lithofacies and eight lithofacies associations are identified in the Poplar River braided river-dominated alluvial fan. The aggradation process of the studied alluvial fan can be divided into flood and interflood periods. The flood-period braided-fluvial deposits, interflood main-channel and braided-trench channel deposits are the facies with best reservoir potential. [ABSTRACT FROM AUTHOR]

The high temperature oxidation behaviour of plasma carburisation on Ni based third generation single crystal superalloy with NiCoCrAlYHf high temperature oxidation protective coating (HY5) is investigated in this paper. The Ni based third generation single crystal superalloy with single HY5 high temperature oxidation protective coating is compared to the plasma carburised samples. HY5 high temperature oxidation protective coating is deposited onto the single crystal superalloy by arc ion plating. The performance of diffusion during thermal cycling at 1100°C was studied. The microstructure and phase composition were examined by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS). The results show that by means of plasma carburisation into the HY5 high temperature oxidation protective coating, its microstructure can be made finer and more uniform, and its microhardness and adhesion to the substructure can be improved markedly. There were smaller quantities of topologically close packed phases (TCPs) and secondary reaction zones (SRZs) precipitated under coating in the single crystal superalloy. [ABSTRACT FROM AUTHOR]

We numerically propose a novel tunable metamaterial with triple bands of negative permeabilities. This metamaterial is composed of an array of single-loop resonators (SLRs) and ferrite slabs, where the SLRs provide two magnetic resonances while the ferrite slabs under an applied dc magnetic bias give rise to the third magnetic resonance. By adjusting the intensity of the dc magnetic bias, it is able to tune all the three magnetic resonances. The-negative features of these resonant bands are investigated by retrieving the constitutive parameters from simulated-parameters. The results in this paper open a new approach for designing tunable multiband metamaterials, which is sure to find extensive applications in fields such as tunable multiband notched ultra-wideband (UWB) antennas, tunable multiband perfect lens, and tunable multiband absorbers. [ABSTRACT FROM PUBLISHER]

BiFeO3 (BFO) nanoparticles were synthesized by the sol-gel method. X-ray diffraction and energy dispersive X-ray spectroscopy indicate no secondary phases are present, and the composition of the BiFeO3 nanoparticles was stoichiometric. Magnetic measurements show that the BiFeO3 nanoparticles exhibit ferromagnetism with spin-glass-like behavior. The results were found to be related to size effects, which partially destroy the long-wavelength cycloid spin structure, and which induce ferromagnetism and spin-glass-like behavior due to diffusion of domain walls and pinning at the nanoparticle surface. [ABSTRACT FROM AUTHOR]

This paper presents some new results on non-regular linearization of non-linear systems. Based on a normal form and a non-regular linearization technique developed recently, the paper first provides a set of calculating formulas for the linearization procedure. As an application, the linearization of bilinear systems is investigated. Then, it presents easily verifiable sufficient conditions for the global (semi-global) (approximate) linearization. Finally, an estimate of the region of attraction for the kth degree approximately linearized systems with state feedback control is given, which illustrates one of the advantages of the approximate linearization. [ABSTRACT FROM AUTHOR]

A change detection approach based on independence component analysis (ICA) was proposed in this letter. Traditional multivariate change detection schemes such as principal component analysis (PCA) were based on 2nd‐order statistics to remove the correlation among multi‐temporal images. However, for the regions where data did not fit a normal distribution, PCA might not be effective. In this letter, ICA was used to separate change information in independent components by reducing the 2nd‐order and higher order dependences in multi‐temporal images. Firstly, the number of images was expanded to the number of land classes by nonlinear band generation. Then, independent component images were obtained based on ICA. The obtained independent component images corresponded to some kind of land or land variation. At last, different kinds of land variation are located by applying maximum likelihood classification (MLC). The experimental results in synthetic and real multi‐temporal images show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]