Characterization of Calcium Phosphate Chitosan Nanocomposite as Plant Growth Promoter

In this study, calcium phosphate-chitosan nanocomposite (CaP-CS NC) was prepared by a convenient and affordable co-precipitation method, and the prepared NC was tested for agriculture application.  Physico-chemicals analyses of the CaP-CS NC were conducted by X-ray diffraction (XRD), scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible spectroscopy (UV-Vis) instruments to determine the structural characteristics, surface topology, chemical composition, function group, and optical properties. The XRD pattern of CaP-CS NC revealed that the average crystallite size was 43 nm. The SEM images showed agglomeration of the CaP-CS NC with a rod-like shape. The EDS spectrum of the CaP-CS NC indicated the presence of Ca, P, O, and N elements. FTIR displayed vibrational peaks for the active functional group such as carboxylic (C=O), amines (N-H), hydroxyl (O-H), and alkyne (C-H). Furthermore, the spectrum of CaP-CS NC showed the bending mode of phosphates at 588.37 cm-1 and 508.45 cm-1. The UV-Vis-NIR spectrum of the prepared nanocomposite indicates the anti-reflection properties, which might be useful in solar cell applications to increase the efficiency of the solar cell. In addition, the prepared CaP-CS NC was tested for the plant growth stimulator properties at the lab scale level, wherein it exhibited substantial growth. Accordingly, the current study suggests that the prepared CaP-CS NC could be used as a plant growth promoter

Evaluation of radionuclides in the terrestrial environment of Western Ghats

The activity concentration of naturally occurring radionuclides in soil samples of an elevated radiation background area of Western Ghats were determined using gamma-ray spectrometry with the aim of evaluating the environmental radioactivity. The annual effective dose equivalent and the radiation hazard indices from the soil activity were estimated to reduce the harmful effects of gamma radiation to the population dwelling in the area. The activity concentrations of 232Th and average outdoor terrestrial gamma dose rate were found to be higher than the world average, this may affect Western Ghats environment in general. Therefore, the radiological risks to the general population from ionizing radiation from the naturally occurring radionuclides in the soil are considered to be significant. However, other radiological hazard indices were found to be within permissible limits

Risk assessment of radioactivity in soils of forest and grassland ecosystems of the Western Ghats, India

Naturally occurring radionuclides were investigated in soil samples collected from a tropical rainforest in the Western Ghats, India. For comparison, a number of soil samples from nearby meadows (open grassland) were also studied using gamma-ray spectrometry. Average values of the activity concentration of radionuclides, outdoor gamma-ray dose rate, annual effective dose equivalent and radiation hazard indices from soil activity were estimated. Significant differences were found between the soils from the forest and meadow sites: the meadow sites contained higher natural radionuclide concentrations than the forest sites. The activity concentration of 232Th and average outdoor gamma-ray dose rates were found to be higher than the global average in both ecosystems, so high gamma radiation appears to affect the Western Ghats environment. Therefore, the radiological risks to the general population from ionizing radiation from the naturally occurring radionuclides in the soil are considered to be significant. However, other radiological hazard indices that were calculated were within acceptable limits

Measurement of radioactivity in an elevated radiation background area of Western Ghats

As part of monitoring the exposure of the general public to natural radioactivity, the activity concentration of naturally occurring radionuclides in soil samples in an elevated radiation background area of Western Ghats was determined using gamma-ray spectrometry. Average values of the activity concentration of radionuclides, outdoor terrestrial gamma dose rate, annual effective dose equivalent and radiation hazard indices from soil activity were estimated. The activity concentrations of 232Th and average outdoor terrestrial gamma dose rate were found to be higher than the world average, possibly affecting the Western Ghats environment in general. Therefore, radiological risks to the general population from ionizing radiation from the naturally occurring radionuclides in the soil are considered to be significant. How- ever, other radiological hazard indices were found to be within permissible limits

Preparation and characterization of nano scale PMMA thin films

64-67Thin films of nano scale poly (methyl methacrylate) (PMMA) were prepared by fast dip coating technique (FDCT). XRD spectra indicated the amorphous nature of the films. The closer SEM inspection revealed that self-assembled mesoscopic cells for both as grown and annealed PMMA films. Low leakage current was observed in the J-V characteristics for the voltage ranges studied. The absence of hysteresis in the <i style="mso-bidi-font-style: normal">J-V characteristics for the forward and reverse sweep direction eliminates the presence of deep traps in the PMMA thin films studied. The observed surface morphology, thermal stability and <i style="mso-bidi-font-style: normal">J-V behaviour indicated that these films could be used as AFM data storage devices as an efficient dielectric layer in field effect organic thin film transistors

<span style="font-size:10.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-US">Structure, surface morphology and optical properties of BaTiO₃ powders prepared by wet chemical method</span>

839-845Barium titanate powders were synthesized by the wet chemical method using the starting materials barium chloride (BaCl2), titanium dioxide (TiO2) and oxalic acid with different calcinations temperature. The XRD pattern of BaTiO3 calcined at 500 <span style="mso-bidi-font-family: " times="" new="" roman""="" lang="EN-GB">˚C showed cubic phase whereas BaTiO3 samples calcined at 700 <span style="mso-bidi-font-family: " times="" new="" roman""="" lang="EN-GB">˚C and above showed tetragonal phase. The crystallite size, strain and dislocation density were calculated from the XRD spectrum. It was found that crystallite size increases with increase of calcination temperature<span style="mso-bidi-font-family: " times="" new="" roman""="" lang="EN-GB">. EDS spectrum was used to identify the composition of the material. Absorption co-efficient (α), extinction co-efficient (K) and optical band gap were estimated from the optical reflectance spectrum. The band gap of the powder was found to be decreasing with the increase of calcination temperature. Nanoparticles of both spherical and rod like in shape were clearly observed in the SEM. </span

PSIDIUM GUAJAVA: A NOVEL PLANT IN THE SYNTHESIS OF SILVER NANOPARTICLES FOR BIOMEDICAL APPLICATIONS.

 Objective: Synthesis of silver nanoparticles (AgNPs) using a simple, cost-effective and environmentally friendly green route approach and to study the antibacterial activity of AgNPs against human pathogens.Methods: Green route approach is used to synthesize AgNPs using Psidium guajava leaf extract. Fourier transform infrared (FTIR) was used to identify the presence of the functional group. X-ray diffraction (XRD) was used to analyze the structure of prepared AgNPs. Energy dispersive X-ray was used to the characteristic to the composition of the prepared nanoparticles. Size and morphology of the prepared AgNPs were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Antibacterials efficiency of prepared AgNPs was tested against Escherichia coli and Staphylococcus aureus by well diffusion methods.Results: FTIR study shows the presence of different functional groups present in the leaves mediated AgNPs. The XRD studies yield diffraction peaks corresponding to face-centered cubic structure of Ag crystals. Spherical shaped AgNPs with a particle size of about ~55 nm were evidenced using FESEM and TEM analysis. Energy dispersive spectrum of the synthesized AgNPs confirms the presence of silver in the prepared nanoparticles. From UV-VIS analysis it is shown that the absorption band was red-shifted from 430 nm to 456 nm. The prepared AgNPs shows good antibacterial activity against E. coli and S. aureus.Conclusions: P. guajava leaf extract is a potential reducing agent to synthesize AgNPs. The green synthesis approach provides cost-effective and eco-friendly nanoparticles, which could be used in biomedical applications

PSIDIUM GUAJAVA: A NOVEL PLANT IN THE SYNTHESIS OF SILVER NANOPARTICLES FOR BIOMEDICAL APPLICATIONS.

 Objective: Synthesis of silver nanoparticles (AgNPs) using a simple, cost-effective and environmentally friendly green route approach and to study the antibacterial activity of AgNPs against human pathogens.Methods: Green route approach is used to synthesize AgNPs using Psidium guajava leaf extract. Fourier transform infrared (FTIR) was used to identify the presence of the functional group. X-ray diffraction (XRD) was used to analyze the structure of prepared AgNPs. Energy dispersive X-ray was used to the characteristic to the composition of the prepared nanoparticles. Size and morphology of the prepared AgNPs were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Antibacterials efficiency of prepared AgNPs was tested against Escherichia coli and Staphylococcus aureus by well diffusion methods.Results: FTIR study shows the presence of different functional groups present in the leaves mediated AgNPs. The XRD studies yield diffraction peaks corresponding to face-centered cubic structure of Ag crystals. Spherical shaped AgNPs with a particle size of about ~55 nm were evidenced using FESEM and TEM analysis. Energy dispersive spectrum of the synthesized AgNPs confirms the presence of silver in the prepared nanoparticles. From UV-VIS analysis it is shown that the absorption band was red-shifted from 430 nm to 456 nm. The prepared AgNPs shows good antibacterial activity against E. coli and S. aureus.Conclusions: P. guajava leaf extract is a potential reducing agent to synthesize AgNPs. The green synthesis approach provides cost-effective and eco-friendly nanoparticles, which could be used in biomedical applications