Magnetron sputtered TiO2 films on a stainless steel substrate: Selective rutile phase formation and its tribological and anti-corrosion performance

In this work, TiO₂ films on 316L stainless steel have been formed by non-reactive magnetron sputtering of TiO₂ target. The effect of a titanium underlayer on the crystalline phase of the TiO₂ film has been investigated in terms of phase evolution, film morphology, corrosion resistance, adhesion strength, hardness and tribological characteristics. Results showed that the titanium underlayer has a significant effect on the phase of the TiO₂ film. Without this underlayer, an anatase TiO₂ film is produced, in consistence with many other investigations. However, it is found that with a titanium underlayer, a rutile TiO₂ film can be directly formed on the substrate. The thickness of the interface layer affects the crystallinity of the rutile film. By controlling the underlayer thickness, the resultant rutile film crystal structure and morphology could be changed accordingly. At an optimized state, the rutile coating shows much improved adhesion, friction, wear and corrosion properties.     

Chrome ore beneficiation challenges & opportunities - A review

Supply of world chromite (chrome ore) has come under severe pressure over the past year driven by strong demand for ferrochrome used in ferroalloy production for making stainless steel. Many of the strategic minerals are inputs into products in fast-changing markets. This article reviews the major process flow sheets in practice for the recovery of chromite values from various types of ores and critical issues related to chromite ore beneficiation. The comprehensive condensation of pertinent facts is intended to provide a single reference source rather than the reader perusing many articles. Emphasis is placed on different processes developed in identifying and solving critical plant problems.     

Mobile Cloud Computing: A Survey,State of Art and Future Directions

In the recent years, cloud computing frameworks such as Amazon Web Services, Google AppEngine and Windows Azure have become increasingly popular among IT organizations and developers. Simultaneously, we have seen a phenomenal increase in the usage and deployment of smartphone platforms and applications worldwide. This paper discusses the current state of the art in the merger of these two popular technologies, that we refer to as Mobile Cloud Computing (MCC). We illustrate the applicability of MCC in various domains including mobile learning, commerce, health/wellness and social medias. We further identify research gaps covering critical aspects of how MCC can be realized and effectively utilized at scale. These include improved resource allocation in the MCC environment through efficient task distribution and offloading, security and privacy.     

Diacetyl—A growth and toxin inhibitor of Aspergilli

Diacetyl (2,3-butanedione) a food additive, was found to be very effective in inhibiting growth and toxin production of Aspergillus flavus, A. versicolor and A. ochraceus when grown on synthetic liquid media and on natural substrates of maize and maize flour. Total growth inhibition of A. flavus and A. versicolor was observed at 250 ppm when grown on liquid medium, whereas 3000–4000 ppm were required to inhibit growth on maize and maize flour. A. ochraceus required 3000 and 6000 ppm of diacetyl for complete inhibition of growth on liquid medium and solid substrates respectively, suggesting it was less sensitive to the compound.     

An integrated design for improving spectral efficiency of FSO communication system in 6G applications

In the case of future access networks, such as 6G-based applications, the free-space optical communication (FSO) technology is an efficient solution. FSO in 6G is extremely popular because of its unique properties, which include ease of installation, high bandwidth, high security, license-free long range, and interference resistance. However, environmental disturbances have a negative impact on the FSO system's functioning. Because of these atmospheric turbulences, the optical information gets restricted, which in turn reduces the link reliability, power density, and distance. This paper proposes a hybrid FSO strategy for improving system efficiency to address these problems. Signal creation is fundamental to every successful communication system. The FSO system consists of three components: the transmitter, the channel medium, and the receiver. The transmitter section includes a continuous wave laser, a Mach–Zehnder modulator, a nonreturn to zero transpose Walsh code generator, and a nonreturn to zero pulse generator. Wavelength division multiplexing-optical code division multiple access-spectrum slicing (WDM-OCDMA-SS) is used to facilitate efficient data transfer after signals have been generated by alternate mark inversion (AMI). In order to boost a weak signal, fused Raman erbium amplifiers (Fuse-RE) are used. Q factor and log bit error rate (BER) are used to assess the performance of the suggested approach. The proposed model has obtained a log BER of −15.3291 for clear air and a Q factor of 8.2922, whereas the performances are implemented using Python. The proposed approach achieves better performance when compared to the existing methodologies.     

Numerical study of thermodiffusion effects on boundary layer flow of nanofluids over a power law stretching sheet

This paper deals with the triple-diffusive boundary layer flow of nanofluid over a nonlinear stretching sheet. In this model, where binary nanofluid is used, the Brownian motion, thermophoresis, and cross-diffusion are classified as the main mechanisms, which are responsible for the enhancement of the convection features of the nanofluid. The boundary layer equations governed by the partial differential equations are transformed into a set of ordinary differential equations with the help of group theory transformations, which is introduced by Blasius (The boundary layers in fluids with little friction, 1950). The variational finite element method is used to solve these ordinary differential equations. We have examined the effects of different controlling parameters, namely the Brownian motion parameter, the thermophoresis parameter, modified Dufour number, nonlinear stretching parameter, Prandtl number, regular Lewis number, Dufour Lewis number, and nanofluid Lewis number on the flow field and heat transfer characteristics. The physics of the problem is well explored for the embedded material parameters through tables and graphs. The present study has many applications in coating and suspensions, movement of biological fluids, cooling of metallic plate, melt-spinning, heat exchangers technology, and oceanography.     

Use of Surfactants to Enhance the Removal of PAHs from Soil

The efficiency of soil remediation is often limited by the low aqueous solubility of Polycyclic Aromatic Hydrocarbons, PAHs. Surfactants can then be used to enhance the removal of PAHs from soils. The dissolution of pure solid deposit of benzo(a)pyrene, B(a)P, has shown that cationic surfactants are the most efficient to increase the aqueous solubility of B(a)P, when compared to neutral or anionic surfactants. In this paper we compare by using soil suspension washings, the efficiency of two surfactants (i) a cationic surfactant, the benzyldimethyl dodecylammonium bromide, BDDA, and (ii) a neutral one, the t-octylphenoxypolyethoxy ethanol, triton X-100. The losses of surfactant, by adsorption on soil or precipitation, were measured together with the release of B(a)P, chosen as a model molecule, representative of all the PAHs. The efficiency of surfactants used in blend was then compared to the efficiency of surfactants alone.     

Combining the evidences of temporal and spectral enhancement techniques for improving the performance of Indian language identification system in the presence of background noise

Language Identification has gained significant importance in recent years, both in research and commercial market place, demanding an improvement in the ability of machines to distinguish between languages. Although methods like Gaussian mixture models, hidden Markov models and neural networks are used for identifying languages the problem of language identification in noisy environments could not be addressed so far. This paper addresses the performance of automatic language identification system in noisy environments. A comparative performance analysis of speech enhancement techniques like minimum mean squared estimation, spectral subtraction and temporal processing, with different types of noise at different SNRs, is presented here. Though these individual enhancement techniques may not yield good performance with different types of noise at different SNRs, it is proposed to combine the evidences of all these techniques to improve the overall performance of the system significantly. The language identification studies are performed using IITKGP-MLILSC (IIT Kharagpur-Multilingual Indian Language Speech Corpus) databases which consists of 27 languages.     

Polymeric encapsulation of 1-2-3 ceramic superconductors

YBa₂Cu₃O_7−x pellets have been found to degrade and lose superconducting properties when exposed to the normal atmosphere for long durations. Hence, coating the superconducting pellets with a polymer to protect it from moisture and CO₂ of the ambient atmosphere is highly desirable. In this paper the criteria of selection of a polymer and some preliminary studies on polymeric encapsulation of 1-2-3 pellets are reported. Fevitite epoxy and stycast have been found to show encouraging results.