Phase transitions and ferroelectric properties in BiScO3-Bi(Zn1/2Ti1/2)O3-BaTiO3 solid solutions

Ceramics solid solutions within the ternary perovskite system Bi(Zn1/2Ti1/2)O3-BiScO3-BaTiO3 were synthesized via solid-state processing techniques. The crystal structure of sintered ceramics was analyzed by x-ray diffraction. A stable perovskite phase was obtained for all compositions with a BaTiO3 content greater than 50 mol %. Furthermore, a change in symmetry from pseudocubic to tetragonal was observed as the mole fraction of BaTiO3 increased. Dielectric measurements show a dielectric anomaly associated with a phase transformation over the temperature range of 30 °C–210 °C for all compositions. Examination of the polarization hysteresis behavior revealed weakly nonlinear hysteresis loops. With these data, ferroelectric phase diagrams were derived showing the transition between the pseudocubic relaxor behavior to the tetragonal normal ferroelectric behavior. This transition was also correlated with changes in the diffuseness parameter

Competitive two-agent scheduling with deteriorating jobs on a single parallel-batching machine

We consider a scheduling problem in which the jobs are generated by two agents and have time-dependent proportional-linear deteriorating processing times. The two agents compete for a common single batching machine to process their jobs, and each agent has its own criterion to optimize. The jobs may have identical or different release dates. The batching machine can process several jobs simultaneously as a batch and the processing time of a batch is equal to the longest of the job processing times in the batch. The problem is to determine a schedule for processing the jobs such that the objective of one agent is minimized, while the objective of the other agent is maintained under a fixed value. For the unbounded model, we consider various combinations of regular objectives on the basis of the compatibility of the two agents. For the bounded model, we consider two different objectives for incompatible and compatible agents: minimizing the makespan of one agent subject to an upper bound on the makespan of the other agent and minimizing the number of tardy jobs of one agent subject to an upper bound on the number of tardy jobs of the other agent. We analyze the computational complexity of various problems by either demonstrating that the problem is intractable or providing an efficient exact algorithm for the problem. Moreover, for certain problems that are shown to be intractable, we provide efficient algorithms for certain special cases

The three dimensional simulating study of the flow and heat transfer in detached vehucular cooling-compartment

Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.To explore the internal flow distributions and heat transfer mechanism in detached cooling-compartment, two three- dimensional models both including the heat exchangers and a full-sized fan model were established and analyzed in this paper. According to the study, the opposite model, on which the heat exchangers were located separately and close to the inlets, was considered to be more efficient. Besides, the opposite arrangement in detached cooling-department offered the possibility to control the mass flow on each heat exchanger independently, which could further increase the cooling efficiency. It deserves more attentions in the future.This study was supported by an NSFC grant (No.51206141) awarded to the first author.am201

Aerosol and cloud microphysics covariability in the northeast Pacific boundary layer estimated with ship-based and satellite remote sensing observations

Ship measurements collected over the northeast Pacific along transects between the port of Los Angeles (33.7°N, 118.2°W) and Honolulu (21.3°N, 157.8°W) during May to August 2013 were utilized to investigate the covariability between marine low cloud microphysical and aerosol properties. Ship-based retrievals of cloud optical depth (τ) from a Sun photometer and liquid water path (LWP) from a microwave radiometer were combined to derive cloud droplet number concentration Nd and compute a cloud-aerosol interaction (ACI) metric defined as ACICCN = ∂ ln(Nd)/∂ ln(CCN), with CCN denoting the cloud condensation nuclei concentration measured at 0.4% (CCN0.4) and 0.3% (CCN0.3) supersaturation. Analysis of CCN0.4, accumulation mode aerosol concentration (Na), and extinction coefficient (σext) indicates that Na and σext can be used as CCN0.4 proxies for estimating ACI. ACICCN derived from 10 min averaged Nd and CCN0.4 and CCN0.3, and CCN0.4 regressions using Na and σext, produce high ACICCN: near 1.0, that is, a fractional change in aerosols is associated with an equivalent fractional change in Nd. ACICCN computed in deep boundary layers was small (ACICCN = 0.60), indicating that surface aerosol measurements inadequately represent the aerosol variability below clouds. Satellite cloud retrievals from MODerate-resolution Imaging Spectroradiometer and GOES-15 data were compared against ship-based retrievals and further analyzed to compute a satellite-based ACICCN. Satellite data correlated well with their ship-based counterparts with linear correlation coefficients equal to or greater than 0.78. Combined satellite Nd and ship-based CCN0.4 and Na yielded a maximum ACICCN = 0.88–0.92, a value slightly less than the ship-based ACICCN, but still consistent with aircraft-based studies in the eastern Pacific

Child feeding and stunting prevalence in left-behind children: a descriptive analysis of data from a central and western Chinese population

Objectives: To examine the effect of parental rural-to-urban internal migration on nutritional status of left-behind children and how this is related to guardianship. Methods: We used UNICEF China’s maternal and child health survey data to investigate stunting prevalence and feeding practices in children left behind by rural-to-urban internal migrant parents. We also assessed the effects of primary guardianship which is related closely with parental migration. Results: Of 6,136 children aged 0-3 years, over one third was left behind by one or both parents. About 13% were left behind by mothers, leaving guardianship primarily to grandmothers. Left-behind status was not associated with stunting, yet children who were cared for primarily by their fathers had a 32% increase of stunting compared to children cared for by the mothers (adjusted odds ratio[aOR]=1.32;95% confidence interval=1.04-1.67). Children with migrant mothers were less likely to receive age-appropriate breastfeeding (aOR=0.04;0.02-0.10) and a minimum acceptable diet (aOR=0.56;0.39-0.79) compared with non-left-behind children. Conclusions: Guardian’s feeding behaviours varied, and was inappropriate for both children affected and not affected by parent’s rural-to-urban internal migration. Community-based infant and young child feeding counselling and support should be provided to all caregivers

Extraction of Electron Self-Energy and Gap Function in the Superconducting State of Bi_2Sr_2CaCu_2O_8 Superconductor via Laser-Based Angle-Resolved Photoemission

Super-high resolution laser-based angle-resolved photoemission measurements have been performed on a high temperature superconductor Bi_2Sr_2CaCu_2O_8. The band back-bending characteristic of the Bogoliubov-like quasiparticle dispersion is clearly revealed at low temperature in the superconducting state. This makes it possible for the first time to experimentally extract the complex electron self-energy and the complex gap function in the superconducting state. The resultant electron self-energy and gap function exhibit features at ~54 meV and ~40 meV, in addition to the superconducting gap-induced structure at lower binding energy and a broad featureless structure at higher binding energy. These information will provide key insight and constraints on the origin of electron pairing in high temperature superconductors.Comment: 4 pages, 4 figure

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