Effect of Particle Concentration on Shape Deformation and Secondary Atomization Characteristics of a Burning Nanotitania Dispersion Droplet

Secondary atomization characteristics of burning bicomponent (ethanol-water) droplets containing titania nanoparticles (NPs) in dilute (0.5% and 1 wt.%) and dense concentrations (5% and 7.5 wt.%) are studied experimentally at atmospheric pressure under normal gravity. It is observed that both types of nanofuel droplets undergo distinct modes of secondary breakup, which are primarily responsible for transporting particles from the droplet domain to the flame zone. For dilute nanosuspensions, disruptive response is characterized by low intensity atomization modes that cause small-scale localized flame distortion. In contrast, the disruption behavior at dense concentrations is governed by high intensity bubble ejections, which result in severe disruption of the flame envelope.

Secondary flow near an undulatory surface induced by wall blocking effect

Prandtl's secondary mean motions of the second kind near an undulating surface were explained in terms of turbulent blocking effect and kinematic boundary conditions at the surface, and its order of magnitude was estimated. Isotropic turbulence is distorted by the undulating surface of wavelength λ and amplitude h with a low slope, so that h « λ. The prime mechanism for generating the mean flow is that the far-field Isotropic turbulence is distorted by the non-local blocking effect of the surface to become anisotropic axisymmetric turbulence near the surface with principal axis that is not aligned with the local curvature of the undulation. Then the local analysis can be applied and the mechanism is similar to the mean flow generation mechanism for homogeneous axisymmetric turbulence over a planer surface, i.e. gradients of the Reynolds stress caused by the turbulent blocking effect generate the mean motions. The results from this simple analysis are consistent with previous exact analysis in which the effects of curvature are strictly taken into account. The results also qualitatively agree with flow visualization over an undulating surface in a mixing-box.

Effect of buffer layer growth conditions on the secondary hexagonal phase content in cubic GaN films on GaAs(001) substrates

In this letter, we investigated the effect of the buffer layer growth conditions on the secondary hexagonal phase content in cubic GaN films on GaAs(0 0 1) substrate. The reflection high-energy electron diffraction (RHEED) pattern of the low-temperature GaN buffer layers shows that both the deposition temperature and time are important in obtaining a smooth surface. Four-circle X-ray double-crystal diffraction (XRDCD) reciprocal space mapping was used to study the hexagonal phase inclusions in the cubic GaN (c-GaN) films grown on the buffer layers. The calculation of the volume contents of the hexagonal phase shows that higher temperature and longer time deposition of the buffer layer is not preferable for growing pure c-GaN film. Under optimized condition, 47 meV FWHM of near band gap emission of the c-GaN film was achieved. (C) 2000 Elsevier Science B.V. All rights reserved.

Effect of secondary ligands' size on energy transfer and electroluminescent efficiencies for a series of europium(III) complexes, a density functional theory study

In this paper, a quantum chemistry method was used to investigate the effect of different sizes of substituted phenanthrolines on absorption, energy transfer, and the electroluminescent performance of a series of Eu(TTA)(3)L (L = [1,10] phenanthroline (Phen), Pyrazino[2,3-f][1,10]phenanthroline (PyPhen), 2-methylprrazino[2,3-f][1,10] phenanthroline(MPP), dipyrido[3,2-a:2',3'-c]phenazine(DPPz), 11-methyldipyrido[3,2-a:2',3'c]phenazine(MDPz), 11.12-dimethyldipyrido[3,2-a:2',3'-c]phenazine(DDPz), and benzo[i]dipyrido[3,2-a:2',3'-c]phenazine (BDPz)) complexes. Absorption spectra calculations show that different sizes of secondary ligands have different effects on transition characters, intensities, and absorption peak positions.

Effect of tailored practice and patient care plans on secondary prevention of heart disease in general practice: cluster randomised controlled trial

Objective: To test the effectiveness of a complex intervention designed, within a theoretical framework, to improve outcomes for patients with coronary heart disease. Design: Cluster randomised controlled multicentre trial. Setting: General practices in Northern Ireland and the Republic of Ireland, regions with different healthcare systems. Participants: 903 patients with established coronary heart disease registered with one of 48 practices. Intervention: Tailored care plans for practices (practice based training in prescribing and behaviour change, administrative support, quarterly newsletter), and tailored care plans for patients (motivational interviewing, goal identification, and target setting for lifestyle change) with reviews every four months at the practices. Control practices provided usual care. Main outcome measures: The proportion of patients at 18 month follow-up above target levels for blood pressure and total cholesterol concentration, and those admitted to hospital, and changes in physical and mental health status (SF-12). Results: At baseline the numbers (proportions) of patients above the recommended limits were: systolic blood pressure greater than 140 mm Hg (305/899; 33.9%, 95% confidence interval 30.8% to 33.9%), diastolic blood pressure greater than 90 mm Hg (111/901; 12.3%, 10.2% to 14.5%), and total cholesterol concentration greater than 5 mmol/l (188/860; 20.8%, 19.1% to 24.6%). At the 18 month follow-up there were no significant differences between intervention and control groups in the numbers (proportions) of patients above the recommended limits: systolic blood pressure, intervention 98/360 (27.2%) v control, 133/405 (32.8%), odds ratio 1.51 (95% confidence interval 0.99 to 2.30; P=0.06); diastolic blood pressure, intervention 32/360 (8.9%) v control, 40/405 (9.9%), 1.40 (0.75 to 2.64; P=0.29); and total cholesterol concentration, intervention 52/342 (15.2%) v control, 64/391 (16.4%), 1.13 (0.63 to 2.03; P=0.65). The number of patients admitted to hospital over the 18 month study period significantly decreased in the intervention group compared with the control group: 107/415 (25.8%) v 148/435 (34.0%), 1.56 (1.53 to 2.60; P=0.03). Conclusions: Admissions to hospital were significantly reduced after an intensive 18 month intervention to improve outcomes for patients with coronary heart disease, but no other clinical benefits were shown, possibly because of a ceiling effect related to improved management of the disease. Trial registration: Current Controlled Trials ISRCTN24081411.

Systematic review of the effect of diet and exercise lifestyle interventions in the secondary prevention of coronary heart disease.

The effectiveness of lifestyle interventions within secondary prevention of coronary heart disease(CHD)remains unclear.This systematic review aimed to determine their effectiveness and included randomized controlled trials of lifestyle interventions, in primary care or community settings, with a minimum follow-up of three months, published since 1990. 21 trials with 10,799 patients were included; the interventions were multifactorial (10), educational (4), psychological (3), dietary (1), organisational (2), and exercise(1). The overall results for modifiable risk factors suggested improvements in dietary and exercise outcomes but no overall effect on smoking outcomes. In trials that examined mortality and morbidity,significant benefits were reported for total mortality (in 4 of 6 trials;overall risk ratio(RR) 0.75 (95%confidence intervals (CI) 0.65, 0.87)), cardiovascular mortality (3 of 8 trials; overall RR 0.63(95%CI 0.47, 0.84)), and nonfatal cardiac events(5 of 9 trials; overall RR 0.68(95%CI 0.55, 0.84)). The heterogeneity between trials and generally poor quality of trials make any concrete conclusions difficult. However, the beneficial effects observed in this review are encouraging and should stimulate further research.

The effect of month of birth on the attainments of primary and secondary school pupils

Background: Previous research has produced conflicting results regarding the effects of season of birth and age-position on cognitive attainments. In Northern Ireland the school year divides the summer season into two providing an opportunity to evaluate the relative contribution of season of birth and age-position effects. Aims: To investigate the relationship between attainment in literacy skills and month of birth for primary and secondary school pupils and to determine the relationship between motor skills and month of birth in primary school pupils. Sample: One thousand one hundred and twenty four primary school pupils participated, and results for key stage 3 (KS3) English and GCSE English Language, for 3,493 Year 10 and 3,697 Year 12 secondary school pupils, respectively, were obtained. Method: Primary school pupils were individually assessed using standardised reading and spelling tests, as well as tests of motor skill. They were also assessed using a standardised group reading test in their class groups. For the secondary school pupils, the results for two year cohorts, in KS3 English and GCSE English language, respectively, were analysed. Results: For the primary school pupils there was evidence of both a season of birth and an age-position effect on all of the cognitive measures, particularly in the early years of schooling. There was, also, evidence of a significant age-position effect at both KS3 and GCSE in favour of the older pupils. For the younger primary school pupils there was evidence of significant age-position effects on both motor measures. Conclusions: The findings from the present study suggest that month of birth may be related to both season of birth and age-position effects. These effects may be compounded, particularly in the early years of primary school, when summer born children are youngest in their year, as in England. In Northern Ireland, age-position effects are also evident in secondary school public examination results, which may have implications for long-term life choices. © 2009 The British Psychological Society.

EFFECT OF ULTRASOUND ON THE KINETICS OF OXIDATION OF OCTAN-2-OL AND OTHER SECONDARY ALCOHOLS WITH SODIUM-BROMATE, MEDIATED BY RUTHENIUM TETRAOXIDE IN A BIPHASIC SYSTEM

The initial rate of oxidation of octan-2-ol and other secondary alcohols to their ketones with NaBrO3, mediated by RuO4 in an aqueous-CCl4 biphasic system, is greater with ultrasonic irradiation than by stirring alone. Under ultrasonic irradiation the initial rate of oxidation of octan-2-ol increases with increasing % duty cycle, [RuO4] and [NaBrO3]. The kinetics of alcohol oxidation appear to be closely linked with the oxidative dissolution of RuO2 to RuO4 by NaBrO3. The observed enhancement in rate with ultrasonic irradiation appear to be association, at least in part, with the increase in interfacial surface area via the formation of an emulsion of aqueous microdroplets containing NaBrO3 in the CCl4 layer containing the non-water-soluble secondary alcohol.

The effect of the magnetic field of the secondary star in dwarf novae

We investigate the effect of a secondary star magnetic field on the accretion disc dynamics of dwarf novae. Simulations have been carried out with a particle code and a dipolar magnetic field structure. The magnetic field acts to remove angular momentum from the disc material, increasing the inward mass flow. This makes the accretion disc more centrally condensed, causing a reduction in the recurrence time for dwarf nova outbursts. We have produced Doppler tomograms and light curves which may be compared with observations. These tomograms are significantly different from those produced in the absence of a magnetic field on the secondary. We derive an upper limit to the magnetic moment of the secondary star in UGem of mu_2<2x10^32 A m^2. The magnetic truncation of the accretion disc produces resonance phenomena similar to those seen in the superoutbursts of SUUMa systems. While these have not been observed for systems like UGem, observations of the SUUMa systems provide us with a useful diagnostic of the disc-field interaction. We are able to place an upper limit on the magnetic moment of the secondary in ZCha of mu_2<1x10^30 A m^2.