Demonstration of Defect-Free and Composition Tunable Ga(x)In(1-x)Sb Nanowires

The Ga(x)In(1-x)Sb ternary system has many interesting material properties, such as high carrier mobilities and a tunable range of bandgaps in the infrared. Here we present the first report on the growth and compositional control of Ga(x)In(1-x)Sb material grown in the form of nanowires from Au seeded nanoparticles by metalorganic vapor phase epitaxy. The composition of the grown Ga(x)In(1-x)Sb nanowires is precisely controlled by tuning the growth parameters where x varies from 1 to ～0.3. Interestingly, the growth rate of the Ga(x)In(1-x)Sb nanowires increases with diameter, which we model based on the Gibbs-Thomson effect. Nanowire morphology can be tuned from high to very low aspect ratios, with perfect zinc blende crystal structure regardless of composition. Finally, electrical characterization on nanowire material with a composition of Ga(0.6)In(0.4)Sb showed clear p-type behavior.     

Eu3+掺杂的ZnO微晶玻璃的制备及其发光性能

通过熔融热处理方法得到了Eu3+掺杂氧化锌微晶玻璃。利用XRD、透射电子显微镜研究了热处理后微晶玻璃的微结构。利用发射光谱研究了其发光性能。结果表明,样品在750℃热处理2h后,在玻璃网络中形成了尺寸约10nm的ZnO纳米晶。结构研究显示结晶后Eu3+进入了ZnO晶格之中。发射光谱显示其发光性能随着ZnO含量的增加以及热处理时间的增加而显著增强。     

3D photon counting integral imaging with unknown sensor positions

Photon counting techniques have been introduced with integral imaging for three-dimensional (3D) imaging applications. The previous reports in this area assumed a priori knowledge of exact sensor positions for 3D image reconstruction, which may be difficult to satisfy in certain applications. In this paper, we extend the photon counting 3D imaging system to situations where sensor positions are unknown. To estimate sensor positions in photon counting integral imaging, scene details of photon counting images are needed for image correspondences matching. Therefore, an iterative method based on the total variation maximum a posteriori expectation maximization (MAP-EM) algorithm is used to restore photon counting images. Experimental results are presented to show the feasibility of the method. To the best of our knowledge, this is the first report on 3D photon counting integral imaging with unknown sensor positions.     

Photon-counting three-dimensional integral imaging with compression of elemental images

In this paper, we present lossless compression of elemental images in photon-counting integral imaging. In order to verify the performance of the compression method applied to low light level three-dimensional (3D) integral imaging, we compute the correlation coefficient and peak to mean square error (PSNR) as metrics for 3D scene reconstruction integrity. We show quantitatively via experiments that a considerable compression of the elemental images in photon-counting integral imaging may be achievable without significant loss in the performance in terms of correlation and PSNR metrics. To the best of our knowledge, this is the first report on applying lossless compression algorithms in photon-counting 3D computational integral imaging.     

The effect of charcoal combustion on iron-ore sintering performance and emission of persistent organic pollutants

A study was carried out into the use of hardwood charcoal as a supplementary fuel in the iron-ore sintering process. The primary fuel was coke breeze with 0%, 20%, 50% and 100% replacement of the energy input with charcoal to produce raw blends with the same heat output as 4.0 wt.% coke breeze. Experimental results indicate that fuel blends where 20% of the heat input was provided by charcoal may improve both the sinter yield and sintering productivity by up to 8%, under normal sintering conditions. In addition, the 20% replacement of coke energy with charcoal would mean that part of the carbon dioxide emitted from the process would be from a renewable source and could be used to offset carbon dioxide emissions from non-renewable fossil fuels. At higher rates of coke breeze energy substitution with charcoal, the lower sintering performance observed was mainly attributed to the lower fixed carbon content and higher volatile matter content of the fuel mix.At the optimum rate of 20% substitution of coke breeze energy input with charcoal, the emission of dioxins were similar to those observed with coke breeze alone as the fuel. However, sintering with 20% energy input from charcoal resulted in a slight increase in middle molecular weight and lower molecular weight PAHs, contributing to a minor increase in B[a]P-eq from 0.15 μg/m³ to 0.17 μg/m³. Overall the results from the laboratory scale tests suggest that it is feasible to substitute 20% of the coke breeze energy input with an equivalent amount of energy from charcoal in the iron-ore sintering process.     

Second- and third-order elastic constants of kesterite CZTS and its electronic and optical properties under various strain rates

In this paper, the continuum approach is used to calculate the second-order elastic constants and the third-order elastic constants of the kesterite CZTS semiconductor. In this approach, by applying the various deformation types to matter and using density functional theory the energy–strain curves are plotted and the corresponding elastic coefficients are extracted. In this paper, the effect of symmetrical strains on CZTS electronic and optical properties has been investigated. For kesterite CZTS, a bandgap of about 0.2 and 1.8 eV with revised Perdew?–Burke?–Ernerhof for solids functional and HSE06 approximation, respectively, ? is obtained. This semiconductor has been conductive in tensile strains and in return, increased its bandgap in compressive strain. In addition, its bandgap becomes indirect in the strains about ?9%. Also, the first peak in the imaginary section of the dielectric function has well conformity to experimental results and its changing process can show the changing process of optical bandgap under external strains such as temperature variations and substrate mismatch.     

A bi-level constraint-oriented outsourcing framework for orchestration of an ERP system

Outputs of each enterprise resource planning (ERP) process in an ERP system could constraint outputs of the next ERP processes. Therefore, it is necessary to determine the ability of ERP processes to support the orchestration of an ERP system. This paper presents a bi-level constraint-oriented outsourcing framework to identify any ERP process that effects on the orchestration of an ERP system. The contribution of the proposed bi-level constraint-oriented outsourcing framework for orchestration of ERP is twofold: (1) it develops the traditional constraints management from a crisp single-criteria environment to a fuzzy multi-criteria environment; and (2) it develops a linear programming technique for multidimensional analysis of preference (LINMAP) model to a fuzzy group bi-level LINMAP model. A case study demonstrates the applicability of the proposed constraint-oriented outsourcing framework for orchestration of ERP modules and processes.     

A generalized method for estimating drifts and drift components of tall buildings under lateral loading

A generalized method for estimating the drifts of tall buildings composed of planar moment‐resisting frames and coupled shear walls under lateral loading is presented. This method establishes the stiffness equations at the story levels by assuming that all the nodes in the same floor of a planar lateral‐force‐resisting unit have an identical lateral displacement, an identical rotation component due to the axial deformations of the columns, and an identical rotation component due to the flexural and shear deformations of the beams. By adopting this simplification, the story drifts contributed by different types of deformations, namely, the axial deformations of the columns or wall piers, the flexural and shear deformations of the beams, and the double‐curvature bending and shear deformations of the columns or wall piers, can be identified. In the formulation of the stiffness matrix, the P‐Delta effects were also incorporated. Through comparisons between the lateral displacements and story drifts computed using the proposed method and those computed using the structural analysis software Midas/Gen, the proposed method is proved to have high accuracy in estimating the drifts of tall building structures.     

Determination of the Optimum Conditions for Leaching of Zinc Cathode Melting Furnace Slag in Ammonium Chloride Media

This research is part of a continuing effort to leach zinc from zinc cathode melting furnace slags (ZCMFSs) to produce zinc oxide. The slag with an assay of 68.05 pct Zn was used in ammonium chloride leaching for zinc extraction. In this paper, the effects of influential factors on extraction efficiency of Zn from a ZCMFS were investigated. The Taguchi’s method based on orthogonal array (OA) design has been used to arrange the experimental runs in order to maximize zinc extraction from a slag. The softwares named Excel and Design-Expert 7 have been used to design experiments and subsequent analysis. OA L ₂₅ (5⁵) consisting of five parameters, each with five levels, was employed to evaluate the effects of reaction time (t = 10, 30, 50, 70, 90 minutes), reaction temperature [T = 313, 323, 333, 343, 353 (40, 50, 60, 70, 80) K (°C)], pulp density (S/L = 20, 40, 60, 80, 100 g/L), stirring speed (R = 300, 400, 500, 600, 700 rpm), and ammonium chloride concentration (C = 10, 15, 20, 25, 30 pctwt), on zinc extraction percent. Statistical analysis, ANOVA, was also employed to determine the relationship between experimental conditions and yield levels. The results showed that the significant parameters affecting leaching of slag were ammonium chloride concentration and pulp density, and increasing pulp density reduced leaching efficiency of zinc. However, increasing ammonium chloride concentration promoted the extraction of zinc. The optimum conditions for this study were found to be t ₄: 70 minutes, T ₅: 353 K (80 °C), (S/L)₂: 40 g/L, R ₃: 500 rpm, and C ₄: 25 pctwt. Under these conditions, the dissolution percentage of Zn in ammonium chloride media was 94.61 pct.