Biosynthesis of Zinc oxide Nanoparticles using Barringtonia acutangula Flower Extract and Evaluation of their Antibacterial and Antioxidant Activities

Zinc oxide (ZnO) has broad applications in various areas. Nanoparticle synthesis using plants is an alternative to conventional physical and chemical methods. It is known that the biological synthesis of nanoparticles is gaining importance due to its simplicity, eco-friendliness and extensive antimicrobial activity. Also, in this study we report the synthesis of ZnO nanoparticles (ZnONPs) using Barringtonia acutangula   flower extract. The prepared ZnO nanoparticles have been characterized by UV–Vis absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM)). The antioxidant activity of the nanoparticles was tested by the α-diphenyl-β-picrylhydrazyl (DPPH) method. Antibacterial properties of the synthesized ZnONPs were evaluated against Staphylococcus aureus and Escherichia coli by disc diffusion method

Corrosion resistance of electrodeposited Ni–B and Ni–B–Si3N4 composite coatings

Corrosion resistance of electrodeposited (ED) and electroless (EL) composite coatings have been a debatable issue in the published literature. The present paper aims to compare the corrosion resistance of ED Ni–B–Si3N4 composite coating with its plain counter part. The ED Ni–B coatings were prepared using Watt’s nickel bath modified with the addition of dimethylamine borane and the ED Ni–B–Si3N4 composite coatings were prepared using the same bath in which Si3N4 particles (mean diameter: 0.80m) were dispersed in it. The structural and morphological characteristics of ED Ni–B and Ni–B–Si3N4 composite coatings were determined using X-ray diffraction (XRD) measurements and scanning electron microscopy (SEM). The corrosion resistances of ED Ni–B and Ni–B–Si3N4 composite coatings, both in asplated and heat treated conditions, in 3.5% NaCl, were evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) studies. The study reveals that the extent of shift in corrosion potential (Ecorr) towards the noble direction, decrease in corrosion current density (icorr), increase in charge transfer resistance (Rct) and decrease in double layer capacitance (Cdl) values with the incorporation of Si3N4 particles in the ED Ni–B matrix is not appreciable, both in as-plated and heat-treated conditions. The occurrence of the second phase angle maximum suggests penetration of the electrolyte via the pores/micro-pores in these coating to create another interface, namely, the electrolyte/substrate. Unlike the nanosized particles, the micron size Si3N4 particles (mean diameter: 0.80m) used in this study is not capable of completely filling all the pores in the coating and allowed diffusion of chloride ions along the interface. The marginal improvement in corrosion resistance observed for ED Ni–B–Si3N4 composite coatings compared to its plain counterpart could have resulted from the decrease in effective metallic area prone to corrosion

Preliminary Screening, Antioxidant and Antimicrobial potential of chaetomorpha antennina and Caulerapa scalpelliformis invitro study

ABSTRACT The seaweeds are a promising source of natural products .From the preliminary phyto chemical analysis we can conclude that the presence of phytochemical in chaetomorpha antennina was more significant when compared to the Caulerapa scalpelliformis. The present study was conducted for the free radical scavenging potentials by using DPPH radical and also for the s antimicrobial properties of chaetomorpha antennina and Caulerapa scalpelliformis in methanolic extract. The tested extract exhibited a dose-dependent free radical scavenging action against DPPH radical and significant antimicrobial potential was observed in Caulerapa scalpelliformis. From the overall results we can conclude that this seaweed could be used against several diseases and in the food processing industry to preserve foods

Electroless Ni–B coatings: preparation and evaluation of hardness and wear resistance

The present work aims to study the hardness and wear resistance of electroless Ni–B coatings. An alkaline bath having nickel chloride as the source of nickel and borohydride as the reducing agent was used to prepare the electroless Ni–B coatings. The structure, microhardness and wear resistance of electroless Ni–B coatings, both in as-plated and heat-treated conditions, were evaluated using X-ray diffraction (XRD), Leitz microhardness tester and a pin-on-disc wear test apparatus. XRD patterns reveal that electroless Ni–B coatings are amorphous in as-plated condition and undergo phase transformation to crystalline nickel and nickel borides upon heat-treatment. The microhardness of the electroless Ni–B coatings increases with increase in heat-treatment temperature and exhibit two maxima in the hardness vs. heattreatment temperature curve. The specific wear rate increases with increase in applied load from 20 to 40 N and at all applied loads, the specific wear rate and coefficient of friction are less for heat-treated electroless Ni–B deposits compared to that obtained for as-plated ones. The wear process of electroless Ni–B coatings is governed by an adhesive wear mechanism

Electroless Ni–P/Ni–B duplex coatings: preparation and evaluation of microhardness, wear and corrosion resistance

The present work deals with the formation of Ni–P/Ni–B duplex coatings by electroless plating process and evaluation of their hardness, wear resistance and corrosion resistance. The Ni–P/Ni–B duplex coatings were prepared using dual baths (acidic hypophosphite- and alkaline borohydride-reduced electroless nickel baths) with both Ni–P and Ni–B as inner layers and with varying single layer thickness. Scanning electron microscopy (SEM) was used to assess the duplex interface. The microhardness, wear resistance and corrosion resistance of electroless nickel duplex coatings were compared with electroless Ni–P and Ni–B coatings of similar thickness. The study reveals that the Ni–P and Ni–B coatings are amorphous in their as-plated condition and upon heat-treatment at 450 ◦C for 1 h, both Ni–P and Ni–B coatings crystallize and produce nickel, nickel phosphide and nickel borides in the respective coatings. All the three phases are formed when Ni–P/Ni–B and Ni–B/Ni–P duplex coatings are heat-treated at 450◦C for 1 h. The duplex coatings are uniform and the compatibility between the layers is good. The microhardness, wear resistance and corrosion resistance of the duplex coating is higher than Ni–P and Ni–B coatings of similar thickness. Among the two types of duplex coatings studied, hardness and wear resistance is higher for coatings having Ni–B coating as the outer layer whereas better corrosion resistance is offered by coatings having Ni–P coating as the outer layer

Effectiveness of Pranayama in Reduction of Stress among Nursing Students in Selected School of Nursing at Kanyakumari District

“A Quasi experimental study to assess the effectiveness of pranayama in reduction of stress among nursing students in selected School of Nursing at Kanyakumari district” was done by Mrs. K.S. Krishnaveni as a partial fulfillment of the requirement for the degree of Master of Science in Nursing at Sri. K. Ramachandran Naidu College of nursing, Thirunelveli under the Tamil Nadu Dr. M.G.R medical university, Chennai during the year of april 2012. OBJECTIVES: • To assess the pre test level of stress among the nursing students in experimental group and control group. • To assess the effectiveness of pranayama to reduce stress among the experimental group and control group. • To compare the pre and post test level of stress among experimental group. • To associate the post test level of stress among nursing students in experimental group and control group with their selected demographic variable. HYPOTHESES: H1: The mean post test level of stress among nursing students in experimental group was lower than the mean post test level of control group. H2: The mean post test level of stress among nursing students in experimental group was lower than their mean pre test level of stress. H3: There was a significant association between the post test level of stress among experimental group with their selected demographic variables. H4: There was a significant association between the post test level of stress among control group with their selected demographic variables. The study was based on Sister Calista Roy's stress adaptation model. The quantitative approach was used in this study. The study was conducted in Grace School of Nursing at Kanyakumari district. The design adopted for this study was quasi experimental pre test and post test control group design to evaluate the effectiveness of pranayama to reduce stress of nursing students. The quata sampling technique was used to select 30 samples for experimental group and 30 samples for control group. The data collection tool used for the study was the Lovibond stress assessment scale. The content validity of the tool was obtained from five clinical experts. The reliability of tool (r=0.87) was established by test retest method. The tool was accepted as reliable by the clinical experts Pilot study was conducted to find out the feasibility of the study and to plan for data analysis. Data collection was done and the data obtained were analyzed in both in terms of descriptive and inferential statistics. THE MAJOR FINDINGS OF THE STUDY

Automation of DMPS Manufacturing by using LabView & PLC

This Paper is to enable the Siemens (Programmable Logic Control) CPU 313-5A to communicate with the Lab VIEW and to control the process accuracy by image processing. The communication between CPU 313-5A and Lab VIEW is via OPC (OLE for Process Control).Process Accuracy is achieved with the use of Labview Image Processing and Gray Scale matching Pattern. Accuracy in the gray scale matching will purely depend on the calibration of the camera with respect to the corresponding image. The digital output from the labview is communicated to PLC via Ethernet Protocol for the industrial process control. With the use of Labview the dead time while using the normal image vision module in PLC can be minimized. Labview uses the gray scale matching technique which is more accurate than the normal image vision module used in PLC