The paper presents some general relations obtaining in relativistic cosmology. It appears from these that a simple cliangc over to anisotropy without the introduction of spin docs not solve any of the out standing difficulties of isotropic cosmological models

Wide band gap metal oxide semiconductors such as zinc oxide ͑ZnO͒ show visible band photolysis that has been employed, among others, to degrade harmful organic contaminants into harmless mineral acids. Metal oxides show enhanced photocatalytic activity with the increase in electronic defects in the crystallites. By introducing defects into the crystal lattice of ZnO nanoparticles, we observe a redshift in the optical absorption shifting from the ultraviolet region to the visible region ͑400-700 nm͒, which is due to the creation of intermediate defect states that inhibit the electron hole recombination process. The defects were introduced by fast nucleation and growth of the nanoparticles by rapid heating using microwave irradiation and subsequent quenching during the precipitation reaction. To elucidate the nature of the photodegradation process, picosecond resolved time correlated single photon count ͑TCSPC͒ spectroscopy was carried out to record the electronic transitions resulting from the de-excitation of the electrons to their stable states. Photodegradation and TCSPC studies showed that defect engineered ZnO nanoparticles obtained through fast crystallization during growth lead to a faster initial degradation rate of methylene blue as compared to the conventionally synthesized nanoparticles.

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We find that the 'jump-into-contact' of the cantilever in the atomic force microscope (AFM) is caused by an inherent instability in the motion of the AFM cantilever. The analysis is based on a simple model of the cantilever moving in a nonlinear force field. We show that the 'jump-into-contact' distance can be used to find the interaction of the cantilever tip with the surface. In the specific context of the attractive van der Waals interaction, this method can be realized as a new method of measuring the Hamaker constant for materials. The Hamaker constant is determined from the deflection of the cantilever at the 'jump-into-contact' using the force constant of the cantilever and the tip radius of curvature, all of which can be obtained by measurements. The results have been verified experimentally on a sample of cleaved mica, a sample of Si wafer with natural oxide and a silver film, using a number of cantilevers with different spring constants. We emphasize that the method described here is applicable only to surfaces that have van der Waals interaction as the tip-sample interaction. We also find that the tip to sample separation at the 'jump-into-contact' is simply related to the cantilever deflection at this point, and this provides a method to exactly locate the surface.

The paper presents some general relations obtaining in relativistic cosmology. It appears from these that a simple cliangc over to anisotropy without the introduction of spin docs not solve any of the out standing difficulties of isotropic cosmological models

We show that a significant enhancement of solar cell efficiency can be achieved in cells fabricated on black Si made using inductively coupled plasma-reactive ion etching (ICP-RIE). The ICP-RIE-fabricated black Si results in an array of vertically oriented defect-free Si nanocones (average height ∼150 nm; apex diameter ∼25 nm) exhibiting an average reflectance ≤2% over most of the relevant solar spectral range. The enabling role of the ultralow reflectance of the nanostructured black Si has been demonstrated using a heterojunction solar cell fabricated by depositing a n-type CdS film on p-Si nanocones followed by a transparent conducting coating of Al-doped ZnO (AZO). The fabricated n-CdS/p-Si heterojunction exhibits promising power conversion efficiency close to 3%, up from a mere efficient 0.15% for a similar cell fabricated on a planar Si. The effect of the fabrication process for the black Si on solar cell performance has been investigated through the measurements of carrier lifetime and surface recombination velocity. The accompanying model and simulation analysis shows that the conical structure leads to the effective dielectric constant varying smoothly from the value of the air at the top to the value of Si at the base over the length of the nanocone, leading to a substantial reduction of its reflectance.

Purpose Information Technology has transformed the banking sector with respect to various systems and processes. Banks have adopted various measures to quicken their business activity and also save cost and time. That is why there has been large requirement of IT in the banking sector. The question arises whether this investment is enhancing the profitability of the bank or not. The purpose of this paper is to examine the presence of profitability paradox in Indian Banking Sector. Design/methodology/approach Data are collected from ten nationalized banks and three private sector banks from 2006 to 2013. The impact of IT expenditure on return on assets and profit efficiency is examined. Profit efficiency is determined using Stochastic Frontier Analysis. Data are collected from annual reports of the banks. Data on IT expenditure are collected through Right to Information Act 2005. Correlation and Panel Regression are used to investigate the relationship between IT expenditure and ROE or Profit Efficiency. Findings The findings of the paper confirm the presence of profitability paradox in the Indian Banking sector. Research limitations/implications Extension of this study to other developing countries of the world will help to identify if any common pattern is there among the developing countries as far as productivity or profitability paradox is concerned. Originality/value There are some studies on the impact of IT on the banking sector in USA and Europe. This type of study however is rare in the context of India or for that matter other developing countries. Therefore, this paper will add new dimension to the existing literature and pave the way for future research in this area.