High-efficiency cell concepts on low-cost silicon sheets

The limitations on sheet growth material in terms of the defect structure and minority carrier lifetime are discussed. The effect of various defects on performance are estimated. Given these limitations designs for a sheet growth cell that will make the best of the material characteristics are proposed. Achievement of optimum synergy between base material quality and device processing variables is proposed. A strong coupling exists between material quality and the variables during crystal growth, and device processing variables. Two objectives are outlined: (1) optimization of the coupling for maximum performance at minimal cost; and (2) decoupling of materials from processing by improvement in base material quality to make it less sensitive to processing variables

Significance of thermal fluctuations and hydrodynamic interactions in receptor-ligand mediated adhesive dynamics of a spherical particle in wall bound shear flow

The dynamics of adhesion of a spherical micro-particle to a ligand-coated wall, in shear flow, is studied using a Langevin equation that accounts for thermal fluctuations, hydrodynamic interactions and adhesive interactions. Contrary to the conventional assumption that thermal fluctuations play a negligible role at high P$\acute{e}$clet numbers, we find that for particles with low surface densities of receptors, rotational diffusion caused by fluctuations about the flow and gradient directions aids in bond formation, leading to significantly greater adhesion on average, compared to simulations where thermal fluctuations are completely ignored. The role of wall hydrodynamic interactions on the steady state motion of a particle, when the particle is close to the wall, has also been explored. At high P$\acute{e}$clet numbers, the shear induced force that arises due to the stresslet part of the Stokes dipole, plays a dominant role, reducing the particle velocity significantly, and affecting the states of motion of the particle. The coupling between the translational and rotational degrees of freedom of the particle, brought about by the presence of hydrodynamic interactions, is found to have no influence on the binding dynamics. On the other hand, the drag coefficient, which depends on the distance of the particle from the wall, plays a crucial role at low rates of bond formation. A significant difference in the effect of both the shear force and the position dependent drag force, on the states of motion of the particle, is observed when the P$\acute{e}$let number is small.Comment: The manuscript has been accepted as an article in Physical Review E Journa

On associating Fast Radio Bursts with afterglows

A radio source that faded over six days, with a redshift of $z\approx0.5$ host, has been identified by Keane et al. (2016) as the transient afterglow to a fast radio burst (FRB 150418). We report follow-up radio and optical observations of the afterglow candidate and find a source that is consistent with an active galactic nucleus. If the afterglow candidate is nonetheless a prototypical FRB afterglow, existing slow-transient surveys limit the fraction of FRBs that produce afterglows to 0.25 for afterglows with fractional variation, $m=2|S_1-S_2|/(S_1+S_2)\geq0.7$, and 0.07 for $m\geq1$, at 95% confidence. In anticipation of a barrage of bursts expected from future FRB surveys, we provide a simple framework for statistical association of FRBs with afterglows. Our framework properly accounts for statistical uncertainties, and ensures consistency with limits set by slow-transient surveys.Comment: Accepted version (ApJL

OPTIMIZATION OF IRBESARTAN TABLET FORMULATION BY 23 FACTORIAL DESIGN

Irbesartan, a widely prescribed anti hypertensive drug belongs to class II under BCS classification and exhibit low and variable oral bioavailability due to its poor aqueous solubility. It needs enhancement in the dissolution rate in its formulation development. Complexation with β-cyclodextrin (βCD) and use of Crospovidone and PVP K 30 are tried for enhancing the dissolution rate of irbesartan in its formulation development. The objective of the present study is optimization of irbesartan tablet formulation employing Crospovidone, βCD and PVP K 30 by 23 Factorial design. Formulation of irbesartan tablets with NLT 85% dissolution in 15 min employing Crospovidone, βCD and PVP K 30 was optimized by 23 Factorial design. Eight irbesartan tablet formulations were prepared using selected combinations of the three Factors as per 23 Factorial designs. Irbesartan tablets were prepared by direct compression method and were evaluated for drug content, hardness, friability, disintegration time and dissolution rate characteristics. The dissolution rate (K1) values were analysed as per ANOVA of 23 Factorial design to find the significance of the individual and combined effects of the three Factors (βCD, Crospovidone and PVP K 30) involved on the dissolution rate of irbesartan tablets formulated. The individual and combined effects of βCD, Crospovidone and PVP K 30 on the dissolution rate (K1) of irbesartan tablets are highly significant (P<0.01). Irbesartan tablet formulation (PFac), disintegrated rapidly with in 1 min and gave very rapid dissolution of irbesartan,100% in 15 min. Higher levels of βCD and lower levels of Crospovidone gave low dissolution rates of irbesartan tablets. The increasing order of dissolution rate (K1) observed with various formulations was CFac> CFa>CFab>CFabc> CF1> CFbc> CFb> CFc. The polynomial equation describing the relationship between the response i. e. percent drug dissolved in 15 min (Y) and the levels of Crospovidone (X1),βCD (X2) and PVP K 30 (X3) based on the observed results is Y = 58.57+34.54 (X1) - 1.89(X2) – 3.60 (X1 X2) -1.82 (X3) +1.50 (X1 X3) + 3.13 (X2 X3) - 4.87 (X1 X2 X3). Based on the above polynomial equation, the optimized irbesartan tablet formulation with NLT 85% dissolution in 15 min could be formulated employing Crospovidone at 27.70% of drug content, βCD at 1:4 ratio of drug: βCD and PVP K 30 at 1% of drug content. The optimized irbesartan tablet formulation gave 86.18 % dissolution in 15 min fulfilling the target dissolution set. The dissolution profile of the optimized Irbesartan tablet formulation was similar to that of commercial brand (IROVEL-150). Hence the formulation of irbesartan tablets with NLT 85% dissolution in 15 min could be optimized by 23 Factorial design

Large area silicon sheet by EFG

Progress in a program to produce high speed, thin, wide silicon sheets for fabricating 10% efficient solar cells is reported. An EFG ribbon growth system was used to perform growth rate and ribbon thickness experiments. A new, wide ribbon growth system was developed. A theoretical study of stresses in ribbons was also conducted. The EFG ribbons were observed to exhibit a characteristic defect structure which is orientation dependent in the early stages of growth

A STUDY ON FINANCIAL RISK AT FOOD AND HOSPITALITY INDUSTRY FOOD AND HOSPITALITY SERVICES

This article explores the critical issue of financial risk management within the context of Food and hospitality industry Food and Hospitality Services, a dynamic player in the food and hospitality industry. In today’s fast-paced and competitive business environment, financial risk is an ever-present concern that can significantly impact the stability and growth of an organization. Food and hospitality industry's success relies on its ability to adapt and proactively address financial risks to ensure long-term sustainability

Novel phytosynthesis of nanoparticles using Indigeneous Australian Plants

Nanoparticles are considered to be the building blocks of nanotechnology. Biosynthesis of nanoparticles using plant material is an exciting and relatively new developing research area in nanobiotechnology. In the present study, Eucalyptus leaves were collected from Olive pink botanical garden, Alice Springs, Australia and were used to synthesize silver nanoparticles. Cubical structured and well monodispersed silver nanoparticles were formed with an average size of 50nm. The formed silver nanoparticles are found to have promising applications in medicine as good antimicrobial agents. To the best of our knowledge this is the first report on exploiting indigeneous Australian plant sources for the synthesis of metallic nanoparticles