Chemical Synthesis of Nano-Sized particles of Lead Oxide and their Characterization Studies

The quantum dots of semiconductor display novel and interesting phenomena that have not been in the bulk material. The color tunability is one of the most attractive characteristics in II-VI semiconductor nanoparticles such as CdS, ZnS, CdSe, ZnSe and PbO. In this work, the semiconductor lead oxide nanoparticles are prepared by chemical method. The average particle size, specific surface area, crystallinity index are estimated from XRD analysis. The structural, functional groups and optical characters are analyzed with using of SEM, FTIR and UV- Visible techniques. The optical band gap value has also been determined.Comment: 8 pages, 5 figures, 2 table

BIOCHEMICAL SCREENING OF MARINE MICROMONOSPORA MARINA KPMS1 (MH036351) AND ITS ANTIBACTERIAL ACTIVITY AGAINST MULTIDRUG RESISTANT BACTERIA

Objective: The present investigation aimed at the screening of pharmaceutically potential antimicrobial metabolite isolated from marine Micromonospora sp. to combat the multidrug‑resistant bacteria. Materials and Methods: The Marine sediments were randomly collected for the isolation of Micromonospora sp., from Gulf of Mannar, East Coastal Region, located at Kayalpatnam, Tuticorin district, Tamil Nadu, India. The Micromonospora sp. was cultivated by serial dilution and crowed plating method on actinomycetes isolation agar. The isolated colonies were identified by morphological, cultural, and biochemical methods. The antibacterial study of Micromonospora sp. was performed on Mueller‑Hinton agar medium against multidrug‑resistant bacteria isolated from urinary tract infection. The antibacterial compound was separated and characterized by Fourier‑transform infrared (FT‑IR) and nuclear magnetic resonance (NMR) spectrum. Results: Based on the morphological, cultural, and biochemical studies, the isolated colonies were found to be the genera of Micromonospora. Among Micromonospora genera, Micromonospora marina KPMS1 strain showed potent antibacterial activity against multidrug‑resistant Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis. The FT‑IR and NMR studies showed the structural elucidation of active compounds derived from M. marina KPMS1. The 16S rRNA sequences of M. marina KPMS1 (MH036351) strain were blasted and deposited in the GenBank of National Center for Biotechnology Information. Conclusion: The results of the study were concluded that microbial compounds are the promising sources of nearly all of the antibiotics produced by marine Micromonospora sp. The detection of new biological compounds was considered to represent a novel species of the genus Micromonospora which have been used for clinical treatment against multidrug‑resistant bacteria and were pharmaceutically important

Numerical Investigation of In-Cylinder Fuel Atomization and Mixing For a GDI Engine

Gasoline Direct Injection (GDI) engines have been shown to have better fuel economy, transient response and cold-start hydrocarbon emissions. Additionally they have lower NOx emissions when operated under lean conditions. However, controlling charge stratification under various load conditions is a major challenge in GDI engines. In the present study a numerical simulations have been performed to understand factors affecting air/fuel mixture preparation under various engine operating conditions. Fuel spray atomization was studied using the two-way coupled Eulerian-Lagrangian approach. Momentum, energy and species equations were solved for the continuous gas phase. The droplet life history was tracked using the Lagrangian approach. Parameters like fuel injection time, fuel mass flow rate and engine speed was varied to determine their effect on air/fuel mixture preparation inside the cylinder. NOMENCLATURE A Area (m 2) B Spalding number Cd Coefficient of discharge Cp Constant pressure specific heat (kJ/kgK) do Injector inner diameter (m) Dp Droplet diameter (m) Fs Surface force (N) Fb Body force (N) g Acceleration due to gravity (m/s 2) he Heat transfer coefficient (WK/m

Ferromagnetism in nanoscale BiFeO3

A remarkably high saturation magnetization of ~0.4mu_B/Fe along with room temperature ferromagnetic hysteresis loop has been observed in nanoscale (4-40 nm) multiferroic BiFeO_3 which in bulk form exhibits weak magnetization (~0.02mu_B/Fe) and an antiferromagnetic order. The magnetic hysteresis loops, however, exhibit exchange bias as well as vertical asymmetry which could be because of spin pinning at the boundaries between ferromagnetic and antiferromagnetic domains. Interestingly, like in bulk BiFeO_3, both the calorimetric and dielectric permittivity data in nanoscale BiFeO_3 exhibit characteristic features at the magnetic transition point. These features establish formation of a true ferromagnetic-ferroelectric system with a coupling between the respective order parameters in nanoscale BiFeO_3.Comment: 13 pages including 4 figures; pdf only; submitted to Appl. Phys. Let

D2EHPA-sulfuric acid system for simultaneous extraction and recovery of nickel ions via supported liquid membrane process

This research addresses the extraction and recovery of nickel ions from real electroplating wastewater using supported liquid membrane (SLM) process. The process involves three main phase system which are feed, organic and stripping phase. The feed phase containing the nickel electroplating wastewater whereas the organic phase containing the liquid membrane which was immobilized in the membrane support. The liquid membrane was prepared by dissolving certain concentration of D2EHPA in kerosene which acts as a carrier and diluent, respectively. Meanwhile, the membrane support employed was commercial polypropylene membrane with features of 100 µm thickness, 71.9% porosity and 0.10 µm effective pore size. On the other hand, the stripping phase consisting of sulfuric acid (H2SO4) solution which acted as a stripping agent. Parameters such as carrier and stripping agent concentration and feed phase flowrate were examined to obtain the best condition for the extraction and recovery efficiency of nickel. The results revealed that about 44 and 55% of nickel ions successfully extracted and recovered, respectively at the best conditions of 1.0 M of D2EHPA, 3.0 M of H2SO4 and 70 ml/min flowrate of feed phase

Use of Corrosion Inhibitors for Steel Protection in Cementitious Composites-A Review

Steel reinforced cementitious composite is one of the most commonly used materials in construction industries. This is mainly because of its excellent mechanical properties that can withstand various types of loading conditions and low cost. But, the corrosion of embedded steel reinforcement is a main problem associated with steel reinforced cementitious composite because it shortens the life of structure. The most important causes of corrosion initiation of steel reinforcement are the ingress of carbon dioxide and chloride ions to the surface of steel. Though, the corrosion initiation of embedded steel can be delayed using corrosion inhibitors. However, after starting of corrosion, the effectiveness of corrosion inhibitor was reported to be reduced significantly and propagation of corrosion becomes more rapidly. Generally, the negative effects of the corrosion inhibitors on properties of cementitious composite were reported to be negligible. Also, the information regarding the long-term performance of the corrosion inhibitors in actual practice are very limited. Various investigations reported several types of corrosion inhibitors in order to control the corrosion of steel that were also used in construction industries commercially. However, some of the corrosion inhibitors were found to be poisonous and harmful to the environment. Therefore, there is need for more research on the corrosion inhibitors in order to find out the suitable inhibitor with low cost and without side effects to the environment