As in classical superalloys based on nickel or cobalt, MC carbides can be easily obtained in cast high entropy alloys (HEA) for enhancing their mechanical properties at high temperatures. These carbides may have also some influence on the hot oxidation properties. They can be also not neutral for the oxidation behavior. To explore their possible influence in this field, an equimolar CoNiFeMnCr reference alloy and two versions containing TaC or HfC carbides were prepared by casting and exposed to air at 1000°C. Their oxidation behaviors were studied by characterizing the obtained corrosion products and the modifications induced in the subsurfaces of the samples. Results show that TaC and HfC are moderately involved in the oxidation phenomena but they obviously influence the Cr and Mn diffusion toward the oxidation front. This seemingly aggravates more the already poor oxidation high temperature resistance of the base alloy. However the harmful effect of the TaC seems to be much lower than the one of the HfC, and the TaC–strengthened CoNiFeMnCr alloy is only a little less resistant against oxidation than the carbide–free reference equimolar alloy.

Nile cabbage (Pistia stratiotes) represents a promising source of biodiesel which has been garnered due to good biomass yield. This study aims to determine the possibility for biodiesel production from Nile cabbage plants collected from a seasonal Pager River. The bio-oil extraction from Nile cabbage leaves was done using soxhlet apparatus. The biodiesel was produced by transesterification of lipids and characterized by GC-FID and the physio-chemical parameters of the produced biodiesel were also performed. The obtained results indicate that, Nile cabbage sample showed a yield of biodiesel (30.30±0.01) %. The biodiesel obtained possess the following fuel properties: density (880.00±0.00)Kg/m3, pH (5.70±0.00), saponification value (137.10±0.09) mg KOH/g, acid value (1.00±0.00) mg KOH/g, iodine value (63.41±0.01) mg I2/100g, flash point (120±0.00)℃, pour point (-6.20±0.03) ℃, colour (brown), moisture content (50.00±0.00)%, and ash content (0.003±0.00)%, and cetane number (49.53±0.05). The GC-FID analysis of the obtained biodiesel showed the presence of C16:0, C18:0, C18:1 and C18:2 as the major constituents of fatty acids (FAs) detected. Therefore, all physiochemical parameters were within the allowable limits, accept only acid value which was slightly higher than the standard limits issued by the American and European (ASTM D 6571:12 and EN 14214:2012) standards. Aquatic weeds are considered a global threat in the aquatic ecosystem, which invoked a lot of attention from the general public and the scientific community. Our findings showed that Nile cabbage biomass could give a significant yield of biodiesel, with desired fuel properties which will initiates a cleaner energy.

In this work, an alloy based on nickel, rich in chromium and designed to be reinforced by MC carbides thanks to the presence of 4wt.% Ta and 2wt.% Hf, was elaborated by conventional casting and exposed to air at three temperatures ranging from 1100 to 1250°C, with follow up of the mass changes due to oxidation. The as–cast microstructure is composed of a dendritic matrix and of eutectic carbides of two types. The major type is (Ta,Hf)C carbide and a minor type is chromium carbide. The isothermal mass gains are slow and their kinetics are of a parabolic type at all temperatures. The alloy demonstrated a chromia–forming behavior in all cases, with the development of an external continuous chromia scale and an internal layer of complex oxide Cr(Ta,Hf)O4. The stability of the external scale during cooling was dependent on the quantity of oxides isothermally formed, i.e. on the oxidation temperature for a given duration. The behavior of the alloy in isothermal oxidation at the considered temperatures is satisfactory but solutions must be found for improving the resistance against cyclic oxidation for the highest temperatures.

Plant growth promoting rhizobacter (PGPR) are adapted to adverse conditions and protect plants from the deleterious effects of some environmental stresses. The aim of the present study, the drought tolerant plants growth promoting bacteria (PGRB) were isolate and characterized from chilli crop (CapsicumannumL). From the rhizosphere soil twelve bacteria were isolated and characterized based on their biochemical and sugar fermentation. The drought stress tolarent stains were screened by production of exo polysaccharides and the plant growth promoting activities like production of IAA and PO4 solubilization were screened. Therefore the present study report that PGRB showed good stress tolerance under drought condition in chilli crop.

The hest for technological advancement in mobile communication is due to augmentation of wireless user. The deployment of 5G mobile communication is less than 4G mobile communication due to challenges in security like cyberwarfare, espionage, critical infrastructure threats. Nevertheless, critic of neurological discomforts, tissue damage in living organisms occur in the existence of EMF radiation. Also, physical scarcity for spectral efficiency arises due to ubiquitous data traffic. Inspite of these disputes data rate, low latency, device to device communication is also a challenge. In this paper we provide a survey on radiation effects, security threats, traffic management.

The electronic industry is the largest and fastest growing manufacturing industry in the world. Electronic waste or E-waste is one of the emerging problems in developed and developing countries. Most of these e-wastes are ending up in dumping yards and recycling centers, posing a new challenge to the environment and policy makers as well. Toxic metals in the E-waste are usually non -biodegradable and they will create harmful long lasting negative consequences on the environment in general and our health particular. Currently E-waste is treated by chemical leaching, it gives more environmental issues due to usage of inorganic chemicals in treatment process. So that, the E-waste can be used for extraction of metals by the process of biological leaching. It is the process of extraction of metal from source by using biological organism. In this process involve numerous ferrous iron and sulfur oxidizing bacteria, acidophilic bacteria which is grown in acid medium. The acid mine drainage (AMD) is the outflow of acidic water from metal mines or coal mines. AMD is recognized as one of the most serious environmental problem in the mining industry. It is also toxic and difficult to managing this water. Due to the presence of sulphide metal in the ore, which is released after the mining process, will react with atmosphere and water forms sulphuric acid which poses potential harm to the environment and eco system. This acid medium is most suitable for the development of acidophilic bacteria’s. In this project, the Acidophilic bacteria in AMD can be suggested for process of recycling in biological leaching of electronic waste. This process can be used for both bioleaching of E-waste and management of mining waste water. The process will suppress the harmfulness in both E-waste and waste mining water.

The non-traditional machining of particulate reinforced metal matrix composites is relatively new. This paper covers studies on match inability of aluminium - Boron carbide metal matrix composites (Al-B4C MMCs) with abrasive water jets (AWJs). Two different compositions of Al-B4C MMCs were processed with various mesh size, abrasive flow rate, transverse rate and water pressure with a view to identify the performance of the abrasive water jet machine for effective processing of MMCs with AWJs. The maximum penetration ability of AWJs in different MMCs was examined by conducting the experiments on trapezoidal shaped Al-B4C MMC specimens, prepared with stir casting method. Optical micrographs of MMC samples and scanning electron microscopic (SEM) examination of AWJ cut surfaces enabled to explain the trends of material removal by the abrasives. Analysis of results clearly indicated the choice of 80 mesh size abrasives, higher water pressure and flow rate and lower transverse rate for effective processing of Al-B4C MMCs with AWJs.

The main objective is to produce an electro spun mat from ardil fibers in combination with polyvinyl alcohol which can be used for medical applications. Ardil fibers are the fibers extracted from the protein obtained from the defatted oil cake of groundnut. The inherent anti-microbial activity of ground nut allows the use of ardil fibers for medical applications. Since ardil fibbers are not capable of forming fibers of its own by electro spinning, they are used in blend with polyvinyl alcohol. Polyvinyl alcohol is chosen mainly because of its biocompatibility, biodegradability and non-toxicity. The electro spun mat produced from ardil and polyvinyl alcohol was checked for anti-microbial activity so that it can be used for medical applications and X-ray diffraction was seen to check the presence of proteins which was absolute. Other test such as moisture vapor transmission rate (MVTR) and thermo gravimetric analysis (TGA) were also conducted to check whether the produced electro spun mat can be used for the required end use. MVTR is checked to check the breathability of the mat and control of moisture. The MVTR is between the acceptance levels which can be used for medical applications. TGA is to check absorption and adsorption. From the results obtained from different results, it is obvious that the produced mat can be used for medical applications.

This paper is aimed at reviewing the application of biological extracts from plants, fungi and bacteria in the synthesis of metal/metal oxide nanoparticles with reference to Ag and TiO2 nanoparticles as a case study. The procedures for the extraction of the biological extracts as well as the chemical instrumentation analysis of the extracts and metal/metal oxide nanoparticles were explained in this review. It was reported that standard chemical test confirms the presence of tannins, alkanoids, flavonoids and terpenoids in various plant extracts, while FTIR characterization of various biological extracts confirms the presence of organic compounds as a capping and reducing agents in the biosynthetic process for the preparation of the nanoparticles. The use of other instrumental techniques such as FESEM, XRD, SEM, EDX, TEM and UV-Visible spectroscopy in the characterization of biosynthesized metal/metal oxide nanoparticles were also explained in this review.