Preparation and Characterization of Ag doped ZnO nanoparticles and its Antibacterial Applications

In the present investigation, AgxZn1-xO nanoparticles (x = 0.05, 0.075, and 0.1%) have been successfully synthesized by precipitation method. The synthesized AgxZn1-xO nanoparticles were characterized by X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and UV–visible spectrophotometer. The XRD studies revealed that the Ag doped ZnO nanoparticles in hexagonal wurtzite structure. The FESEM and HRTEM images show that the presence of aggregated nanoparticles. The EDX spectrum confirmed the present metals in AgxZn1-xO nanoparticles which indicated the purity of the sample. The FTIR and Raman spectrum indicates that the present functional groups and crystalline quality of Ag doped ZnO nanoparticles. The optical properties were measured by using UV–Vis Spectrophotometer. The antibacterial activity of the samples are examined and also compared with standard drugs

Synthesis, structural and optical properties of Mn doped ZnO nanoparticles and their antibacterial application

In the present investigation, MnxZn1-xO (x = 0.05, 0.075 and 0.1%) nanoparticles have been synthesized by simple precipitation method. Their structural, morphological and optical properties were examined by using X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray spectroscopy (EDX), High resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Differential scanning calorimetry (DSC) and UV-Visible spectroscopy. The Powder X-ray diffraction studies confirmed that the manganese doped ZnO have a single phase nature with hexagonal wurtzite structure and Mn successfully incorporated into the lattice position of Zn in ZnO lattice. The FESEM and HRTEM images are coincided with each other for aggregation of particles in nature. The elemental analysis of doped samples has been evaluated by EDX. The antibacterial activity of Mn doped ZnO nanoparticles has also been examined

Comparative Analysis of Integrated Wideband/Narrow Band Antenna for Cognitive Radio Applications

Cognitive radio is an inventive system to wireless technologies in which radios are designed with an astonishing level of intelligence and agility. This handles the available spectrum in an expedient manner to avoid spectrum scarcity. The cognitive radio antenna consists of integrated wideband and narrow band antenna in same substrate which is taxing task. A UWB antenna is pondered for the wide band operation which has the bandwidth of 7.5 GHz respectively is used for sensing vacant slots in the spectrum. For narrowband antenna the frequency and pattern reconfigurable antenna is usually suggested which is used for transmission of data through the vacant slots from the outcomes of sensing antenna. In this paper the various cognitive radio antennas are investigated in tremendously

Steady state performance evaluation of variable geometry twin-entry turbine

This paper presents the results from an experimental investigation conducted on different turbine designs for an automotive turbocharger. The design progression was based on a commercial nozzleless unit that was modified into a variable geometry single and twin-entry turbine. The main geometrical parameters were kept constant for all the configurations and the turbine was tested under steady flow conditions. A significant depreciation in efficiency was measured between the single and twin-entry configuration due to the mixing effects. The nozzleless unit provides the best compromise in terms of performance at different speeds. The twin-entry turbine was also tested under partial and unequal admissions. Based on the test results a method to determine the swallowing capacity under partial admission given the full admission map is presented. The test results also showed that the turbine swallowing capacity under unequal admission is linked to the full admission case

Study on stepped type basin in a solar still

In this work a stepped solar still is used to enhance the productivity of the solar still. The concept of integrating the stepped solar still along with inclined flat plate collector is introduced in this research work. In this stepped type solar still, a conventional basin of area 1 m2, was placed at the bottom. Another absorber plate, stepped type was fixed on the top of the conventional basin. It consists of subsequent trays and inclined flat plate collectors. This ensures an additional exposure area which augments the evaporation rate. Experiments were conducted with various depths in the conventional basin. A conventional still was fabricated and run parallel with the experimental set up for comparison. Sensible heat storage mediums such as rocks, pebbles were added to the top basin of stepped trays and bottom conventional basins to increase the temperature of water in the still. Wicks were placed on the inclined flat plate collector to augment the evaporation rate due to capillarity. A higher evaporation rate is obtained in the packing material with wicks and pebbles in tray combinations. Theoretical analysis was performed and it agrees with experimental values. Efficiency of the system was also compared with conventional solar still

An attack resistant physical unclonable function smart optical sensors for internet of things for secure remote sensing

COVID-19 pandemic scenario makes extensive use of remote temperature sensors, using IoT devices and communications. Earlier, flexible organic-inorganic luminous inks were used to design and print univocal smart labels based on QRCs (quick response codes) on medical substrates (protective masks and adhesive). Through simultaneous combination of luminescence thermometry and PUFs (physical unclonable functions), temperature measurements in non-contacts, identifications, and connections with IoTs. PUFs are extremely helpful for hardware security, but are open to attacks from MLTs (machine learning techniques) that mimic the behaviours of CRPs (controvert-response pairs). The study suggests ARPUFs architecture that implements two-round controverts to randomise the mapping of CRPs in order to satisfy the unpredictability requirements for resistances, intriguing examples on the usages of organic/inorganic hybrids luminous inks changed by lanthanide ions for creating smart labels with the ability of sensing temperatures including maximal thermal sensitivities up to 1.46%K and uncertainties of 0.2 K, along with authentications like methodology accuracies (98.4%), precisions (99.6%), and recalls (87.7%). Proposed methodology of univocal identifications and monitoring of mobile optical temperatures in individuals, enable control of accesses to restricted areas and medical information transfers for post-medical evaluation results in opening the door to new generations of mobile-assisted eHealths (mHealth-mobile-assisted eHealths)