Radiative heat transfer during turbulent combustion

We investigate the radiative heat transfer in a co-flowing turbulent nonpremixed propane-air flame inside a three-dimensional cylindrical combustion chamber. The radiation from the luminous flame, which is due to the appearance of soot particles in the flame, is studied here, through the balance equation of radiative transfer which is solved by the Discrete Ordinates Method (DOM) coupling with a Large Eddy Simulation (LES) of the flow, temperature, combustion species and soot formation. The effect of scattering is ignored as it is found that the absorption dominates the radiating medium. Assessments of the various orders of DOM are also made and we find that the results of the incident radiation predicted by the higher order approximations of the DOM are in good agreement

Large eddy simulation for turbulent non-premixed fuel-rich combustion in a cylindrical combustor

No abstract available

Effect of stocking density on growth of tiger shrimp (Penaeus monodon Fab.) fed on commercial formulated diets

Three different stocking rates in a semi-intensive pilot shrimp project was adopted in duplicates of three treatments designated as T1, T2 and T3 having initial per meter square stocking density of shrimp of 40, 44 and 51 respectively of 0.025g size post larva. The study was conducted for 84 days. Commercial pelleted diets designated as starter - 1, 2, 3 and grower were fed at a satiation level during the study period with a feeding frequency of 4 to 5 times per day. Feed rationing was based on the survivability, body weight and tray checking. 5-25% of the pond water was exchanged daily. Sampling was done for growth after every 2nd week. Monthly sampling was done for mortality in the ponds. Mean weight gain of the shrimp in treatments T1, T2 and T3 were 16.96 ± 1.14, 16.04 ± 1.38 and 14.08 ± 1.17g respectively and T1 with a low stocking density showed a significantly best growth among the treatments. Total mortality in treatments T1, T2 and T3 were as 30.00, 39.77 and 31.37% respectively. Significantly higher feed conversion ratio (FCR) of 1.87 was obtained with shrimp in treatment T3 followed by shrimp in T1 and T2 with FCR values of 1.70 and 1.41 respectively. A positive correlation of growth and salinity was observed during the study. Total production per unit area was the highest in the treatment T3 (4928 kg/ha) and followed by T1 (4747 kg/ha) and T2 (4251 kg/ha). The result show significantly negative correlation between individual growth and density

Combining a high DHA multi-nutrient supplement with aerobic exercise: protocol for a randomised controlled study assessing mobility and cognitive function in older women.

There is a complex interplay between cognition and gait in older people, with declines in gait speed coexisting with, or preceding cognitive decline. Omega-3 fatty acids, B vitamins, vitamin E, phosphatidylserine, and Ginkgo Biloba show promise in preserving mobility and cognitive function in older adults. Exercise benefits mobility and there is evidence suggesting positive interactions between exercise and omega-3 fatty acids on physical and cognitive function in older adults. Non-frail or pre-frail females aged ≥60 years are included in a randomized placebo controlled study. Intervention groups are: high DHA multi-nutrient supplement and exercise, placebo supplement and exercise, high DHA multi-nutrient supplement, and placebo supplement. Dietary supplementation is 24 weeks. The exercise intervention, two cycle ergometer classes per week, is for the final 12 weeks. The primary outcome is habitual walking speed, secondary outcomes include gait variables under single and dual task, five times sit to stand, verbal and spatial memory, executive function, interference control and health related quality of life. Blood fatty acids, serum homocysteine, dietary intake, physical activity, and verbal intelligence are measured to assess compliance and control for confounding factors. The study is registered at www.clinicaltrials.gov (NCT03228550)

Macronutrient status and yield stability of arecanut (Kahikuchi) under integrated nutrient management practice in Assam

A long term field   experiment was carried out in clay-loam soil at ICAR-CPCRI, Kahikuchi campus,   Guwahati, Assam during 2000-2012 with arecanut variety Kahikuchi with seven   nutrient combinations. The treatments included control (T1), 100 per cent   vermicompost (T2), 200 per cent vermicompost (T3), 100 per cent chemical   fertilizer (T4), 50 per cent vermicompost + 50 per cent chemical fertilizer   (T5), 1/3rd vermicompost + 2/3rd chemical fertilizer   (T6) and 2/3rd vermicompost + 1/3rd chemical fertilizer   (T7). The treatment T7 produced highest fresh ripened arecanut yield of 16.7   kg i.e., about 3.6 kg dry chali per palm. Positive correlations were   obtained between yield of arecanut and soil available N, P, K content.   Significant and positive correlation was found between leaf N, P, K and   available N, P, K content in surface and sub-surface soil. Available N, P and   K content increased over the year under nutrient applied plot that reflected   in yield of arecanut. The average yield in various treatments followed in the   order of T7 > T5 = T6 > T2 = T3 > T4 > T1. The application of   targeted, sufficient and balanced quantities of organic and inorganic   fertilizer will be the need of the hour to make nutrients available for   higher yield, soil fertility maintenance and agricultural sustainability   without polluting environment

Sustainability of soil health and system productivity through arecanut based cropping system in the NE Region of India

The North-Eastern part of India contains seven states out of which, Assam is the major producer of arecanut. An attempt was made to study the impact of arecanut based multiple cropping system with proper utilization of recyclable resources on the long-term sustainability of acid soil at Kahikuchi. A long term arecanut based High-Density Multispecies Cropping System garden comprised of two models viz., Model-1 (M1): arecanut (Areca catechu), black pepper (Piper nigrum), banana (Musa spp.), citrus (Citrus limon) and clove (Syzygium aromaticum) and Model-2 (M2): arecanut, black pepper, banana, citrus and nutmeg (Myristica fragrans) as component crops was used. Both the models were sub-divided into three treatments viz., Full dose of recommended fertiliser (T1), 2/3rd of the recommended dose (T2) and 1/3rd of the recommended dose (T3) combined with treatment-wise recycling available biomass in the form of vermicompost and each treatment was replicated thrice. The results indicated that the quantity of recyclable biomass generated ranged between 8.27 to 12.23 t ha-1 year-1 and 8.11 to 12.38 t ha-1 year-1 in model-1 and model-2, respectively and revealed that the T2 treatment in both models improved the soil properties with respect to soil pH, organic carbon, available N, P and K status. Economics of the cropping system revealed that the maximum return was obtained from both Models under T2. The average benefit:cost ratio of T1, T2 & T3 was 3.38, 4.42 & 3.47 under model-1 and 3.34, 4.08 and 3.40 under model-2, respectively. Sustenance of soil pH above 5.0 over the years in the arecanut rhizosphere in both the models were found under T2, but T1 and T3 treatments showed a slow declining of pH towards increasing soil acidity

The Need to Increase Awareness and Access to Cochlear Implantation

Some degree of disabling hearing loss is present in 466 million people world-wide, representing 5% of the world’s population and the majority of these are adults over 65 years old. Hearing loss is associated with increased risks of social isolation, depression, dementia, stroke, vision loss, diabetes and mortality. It is in the top five causes of years lived with disability in 2015, 2016 and 2017 for males and top 10 for females. Hearing aids are a suitable treatment for mild to moderate loses but for some they do not provide enough benefit. Cochlear implantation is a proven and effective treatment for bilateral severe to profound hearing loss, yet despite good funding in high income countries, the utilisation of CI is poor (less than 10% of suitable patients), especially in the older adult population who arguably need it most. Prevalence data shows that hearing loss increases with age, but the provision of implants in the over 65 s is even lower, despite there being no clinical barriers to older adults receiving a CI. Survey data shows that awareness activities are needed for both professionals and the general population to improve knowledge of what a CI is and how it can help

Heavy flavor diffusion in weakly coupled N=4 Super Yang-Mills theory

We use perturbation theory to compute the diffusion coefficient of a heavy quark or scalar moving in N=4 SU(N_c) Super Yang-Mills plasma to leading order in the coupling and the ratio T/M<<1. The result is compared both to recent strong coupling calculations in the same theory and to the corresponding weak coupling result in QCD. Finally, we present a compact and simple formulation of the Lagrangian of our theory, N=4 SYM coupled to a massive fundamental N=2 hypermultiplet, which is well-suited for weak coupling expansions.Comment: 22 pages, 4 figures; v3: error corrected in calculations, figures and discussion modified accordingl

Managing information cycles for intra-organisational coordination of humanitarian logistics

As the humanitarian aid sector is expanding, the need for enhancing coordination capabilities increases as well. This holds especially for the area of logistics, because humanitarian operations typically take place in unstable and risky environments, where infrastructure is poor, while staff turnover is high. The effectiveness of humanitarian logistics critically depends on the availability and quality of logistics support information, but data is often scarce and ICT support to remote areas is limited. The challenges caused by these constraints call for conceptual insight into the intra-organisational coordination process in humanitarian aid. In order to assess current practice of intra-organisational logistics information management for humanitarian aid, we combine humanitarian logistics and organisational literatures to develop a model that ties in information cycles with activity cycles that ultimately should lead to value creation. The model serves as a basis to analyse coordination practice at the Dutch filial of Médecins Sans Frontiéres (MSF-Holland) and develop implications for research and practice

Large eddy simulation of a turbulent non-premixed propane-air reacting flame in a cylindrical combustor

Large Eddy Simulation (LES) is applied to investigate the turbulent non-premixed combustion flow, including species concentrations and temperature, in a cylindrical combustor. Gaseous propane (C3H8) is injected through a circular nozzle which is attached at the centre of the combustor inlet. Preheated air with a temperature of 773 K is supplied through the annulus surrounding of this fuel nozzle. In LES a spatial filtering is applied to the governing equations to separate the flow field into large-scale and small-scale eddies. The large-scale eddies which carry most of the turbulent energy are resolved explicitly, while the unresolved small-scale eddies are modelled using the Smagorinsky model with Cs = 0.1 as well as dynamically calibrated Cs. The filtered values of the species mass fraction, temperature and density, which are the functions of the mixture fraction (conserved scalar), are determined by integration over a beta probability density function (β-PDF). The computational results are compared with those of the experimental investigation conducted by Nishida and Mukohara. According to this experiment, the overall equivalence ratio of 0.6, which is calculated from the ratio of the air flow rate supplied to the combustion chamber to that of the stoichiometric reaction, is kept constant so that the turbulent combustion at the fuel nozzle exit starts under the fuel-rich conditions