Crystal Structure, Infrared Spectra, and Microwave Dielectric Properties of Temperature-Stable Zircon-Type (Y,Bi)VO<inf>4</inf> Solid-Solution Ceramics

A series of (Bi 1-x Y x )VO 4 (0.4 ≤ x ≤ 1.0) ceramics were synthesized using the traditional solid-state reaction method. In the composition range of 0.4 ≤ x ≤ 1.0, a zircon-type solid solution was formed between 900 and 1550 °C. Combined with our previous work (scheelite monoclinic and zircon-type phases coexist in the range of x < 0.40), a pseudobinary phase diagram of BiVO 4 -YVO 4 is presented. As x decreased from 1.0 to 0.40, the microwave permittivity (ϵ r ) of (Bi 1-x Y x )VO 4 ceramics increased linearly from 11.03 to 30.9, coincident with an increase in the temperature coefficient of resonant frequency (TCF) from -61.3 to +103 ppm/°C. Excellent microwave dielectric properties were obtained for (Bi 0.3 Y 0.7 )VO 4 sintered at 1025 °C and (Bi 0.2 Y 0.8 )VO 4 sintered at 1075 °C with ϵ r ∼ 19.35, microwave quality factor (Qf) ∼ 25 760 GHz, and TCF ∼ +17.8 ppm/°C and ϵ r ∼ 16.3, Qf ∼ 31 100 GHz, and TCF ∼ -11.9 ppm/°C, respectively. Raman spectra, Shannon's additive rule, a classical oscillator model, and far-infrared spectra were employed to study the structure-property relations in detail. All evidence supported the premise that Bi-based vibrations dominate the dielectric permittivity in the microwave region

A new technology for preventing fouling and energy conservation

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Fouling in heat exchange equipment is a common problem unsolved in many industries, and is also an important bottleneck that restricts the production. Among the existing technologies of solving the problem of preventing fouling and heat-transfer enhancement, the fluidized bed preventing - fouling and heat-transfer enhancement technology is an effective method with broad application prospects, which can online prevent fouling and enhance heat transfer in heat exchange equipment such as evaporator, preheater, condenser, cooler, reboiler, industrial boiler, gravity heat pipe, and so on. In this paper, the principle and characteristics of this technology are briefly introduced, and some industrial application achievements of the technology are also presented.cf201

Fabrication of CuO nanoparticle interlinked microsphere cages by solution method

Here we report a very simple method to convert conventional CuO powders to nanoparticle interlinked microsphere cages by solution method. CuO is dissolved into aqueous ammonia, and the solution is diluted by alcohol and dip coating onto a glass substrate. Drying at 80 °C, the nanostructures with bunchy nanoparticles of Cu(OH)2can be formed. After the substrate immerges into the solution and we vaporize the solution, hollow microspheres can be formed onto the substrate. There are three phases in the as-prepared samples, monoclinic tenorite CuO, orthorhombic Cu(OH)2, and monoclinic carbonatodiamminecopper(II) (Cu(NH3)2CO3). After annealing at 150 °C, the products convert to CuO completely. At annealing temperature above 350 °C, the hollow microspheres became nanoparticle interlinked cages

Effect of dried tangerine peel extract supplementation on the growth performance and antioxidant status of broiler chicks

The aim of this study was to evaluate the effects of dried tangerine peel extract (DTPE) supplementation on the growth performance and immune and antioxidant status of broiler chicks. A total of 525day-old, male, Arbour Acres (AA) broiler chicks were fed a basal diet (CTR) either with or without 80, 160, 240 and 480mg DTPE/kg diet. The chicks were randomly assigned into five dietary groups for a 42-day experiment. There were seven replicates per group and 15 chicks per replicate. At 42 days of age, two birds from each cage were selected for blood sampling. The dietary DTPE supplementation linearly increased the body weight and the average daily gain (p=.03; p=.03) and quadratically increased the average daily feed intake (p=.02) during the starter period. In addition, the plasma lysozyme level in the 80 or 160mg/kg DTPE group increased compared to the CTR group (p=.02 and .07, respectively). Chicks fed 80-mg/kg DTPE reduced the malondialdehyde concentration (p=.02) compared with birds fed the CTR diets. Moreover, the plasma glutathione peroxidase activities in the low DTPE dietary groups (80 and 160mg/kg) were higher than in the CTR (p<.01) and 240mg/kg DTPE group (p<.01 and p=.02, respectively). The results of the present study indicate that dietary DTPE with low supplemental dosage (<= 160mg/kg) might positively modulate the systemic antioxidative defence property of chicks

Multi-response analysis in the material characterisation of electrospun poly (lactic acid)/halloysite nanotube composite fibres based on Taguchi design of experiments: fibre diameter, non-intercalation and nucleation effects

Poly (lactic acid) (PLA)/halloysite nanotube (HNT) composite fibres were prepared by using a simple and versatile electrospinning technique. The systematic approach via Taguchi design of experiments (DoE) was implemented to investigate factorial effects of applied voltage, feed rate of solution, collector distance and HNT concentration on the fibre diameter, HNT non-intercalation and nucleation effects. The HNT intercalation level, composite fibre morphology, their associated fibre diameter and thermal properties were evaluated by means of X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), imaging analysis and differential scanning calorimetry (DSC), respectively. HNT non-intercalation phenomenon appears to be manifested as reflected by the minimal shift of XRD peaks for all electrospun PLA/HNT composite fibres. The smaller-fibre-diameter characteristic was found to be sequentially associated with the feed rate of solution, collector distance and applied voltage. The glass transition temperature (T g) and melting temperature (T m) are not highly affected by varying the material and electrospinning parameters. However, as the indicator of the nucleation effect, the crystallisation temperature (T c) of PLA/HNT composite fibres is predominantly impacted by HNT concentration and applied voltage. It is evident that HNT’s nucleating agent role is confirmed when embedded with HNTs to accelerate the cold crystallisation of composite fibres. Taguchi DoE method has been found to be an effective approach to statistically optimise critical parameters used in electrospinning in order to effectively tailor the resulting physical features and thermal properties of PLA/HNT composite fibres

Galaxy Clusters Associated with Short GRBs. II. Predictions for the Rate of Short GRBs in Field and Cluster Early-Type Galaxies

We determine the relative rates of short GRBs in cluster and field early-type galaxies as a function of the age probability distribution of their progenitors, P(\tau) \propto \tau^n. This analysis takes advantage of the difference in the growth of stellar mass in clusters and in the field, which arises from the combined effects of the galaxy stellar mass function, the early-type fraction, and the dependence of star formation history on mass and environment. This approach complements the use of the early- to late-type host galaxy ratio, with the added benefit that the star formation histories of early-type galaxies are simpler than those of late-type galaxies, and any systematic differences between progenitors in early- and late-type galaxies are removed. We find that the ratio varies from R(cluster)/R(field) ~ 0.5 for n = -2 to ~ 3 for n = 2. Current observations indicate a ratio of about 2, corresponding to n ~ 0 - 1. This is similar to the value inferred from the ratio of short GRBs in early- and late-type hosts, but it differs from the value of n ~ -1 for NS binaries in the Milky Way. We stress that this general approach can be easily modified with improved knowledge of the effects of environment and mass on the build-up of stellar mass, as well as the effect of globular clusters on the short GRB rate. It can also be used to assess the age distribution of Type Ia supernova progenitors.Comment: ApJ accepted versio

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society