Radiative and non-radiative effects of a substrate on localized plasmon resonance of particles

Experiments have shown strong effects of some substrates on the localized plasmons of metallic nano particles but they are inconclusive on the affecting parameters. Here we have used Discrete Dipole Approximation in conjunction with Sommerfeld integral relations to explain the effect of the substrates as a function of the parameters of incident radiation. The radiative coupling can both quench and enhance the resonance and its dependence on the angle and polarization of incident radiation with respect to the surface is shown. Non-radiative interaction with the substrate enhances the plasmon resonance of the particles and can shift the resonances from their free-space energies significantly. The non-radiative interaction of the substrate is sensitive to the shape of particles and polarization of incident radiation with respect to substrate. Our results show that plasmon resonances in coupled and single particles can be significantly altered from their free-space resonances and are quenched or enhanced by the choice of substrate and polarization of incident radiation.Comment: 14 pages, 4 figure

Load Flow Analysis with UPFC under Unsymmetrical Fault Condition

This paper addresses the comparative load flow analysis with and without Unified Power Flow Controller (UPFC) for six buses, three phase transmission line under unsymmetrical faults (L-G, L-L and L-L-G) in simulation model. Unified Power Flow Controller (UPFC) is a typical Flexible AC Transmission System (FACTS) device playing a vital role as a stability aid for large transient disturbances in an interconnected power system. The main objective of this paper is to improve transient stability of the six bus system. Here active and reactive power on load bus of the system considered has been determined under different fault conditions. UPFC has been connected to the system and its effects on power flow and voltage profile of test system has been determined with various line data and bus data for six buses, three lines power system and simulation model by using simulation toolbox has been developed. In this work a versatile model is presented for UPFC inherent order to improve the transient stability and damp oscillation. Index Terms – Unified Power Flow Controller (UPFC), Control, simulation, transients, line to ground fault (L-G), double line to ground fault (L-L-G), double line fault (L-L

Designing sparse sensing matrix for compressive sensing to reconstruct high resolution medical images

Compressive sensing theory enables faithful reconstruction of signals, sparse in domain $\Psi$, at sampling rate lesser than Nyquist criterion, while using sampling or sensing matrix $\Phi$ which satisfies restricted isometric property. The role played by sensing matrix $\Phi$ and sparsity matrix $\Psi$ is vital in faithful reconstruction. If the sensing matrix is dense then it takes large storage space and leads to high computational cost. In this paper, effort is made to design sparse sensing matrix with least incurred computational cost while maintaining quality of reconstructed image. The design approach followed is based on sparse block circulant matrix (SBCM) with few modifications. The other used sparse sensing matrix consists of 15 ones in each column. The medical images used are acquired from US, MRI and CT modalities. The image quality measurement parameters are used to compare the performance of reconstructed medical images using various sensing matrices. It is observed that, since Gram matrix of dictionary matrix ($\Phi \Psi \mathrm{)}$ is closed to identity matrix in case of proposed modified SBCM, therefore, it helps to reconstruct the medical images of very good quality

Estimation of Heavy Metal Contamination in Groundwater and Development of a Heavy Metal Pollution Index by Using GIS Technique

Heavy metal (Al, As, Ba, Cr, Cu, Fe, Mn, Ni, Se and Zn) concentration in sixty-six groundwater samples of the West Bokaro coalfield were analyzed using inductively coupled plasma-mass spectroscopy for determination of seasonal fluctuation, source apportionment and heavy metal pollution index (HPI). Metal concentrations were found higher in the pre-monsoon season as compared to the post-monsoon season. Geographic information system (GIS) tool was attributed to study the metals risk in groundwater of the West Bokaro coalfield. The results show that 94 % of water samples were found as low class and 6 % of water samples were in medium class in the post-monsoon season. However, 79 % of water samples were found in low class, 18 % in medium class and 3 % in high class in the pre-monsoon season. The HPI values were below the critical pollution index value of 100. The concentrations of Al, Fe, Mn, and Ni are exceeding the desirable limits in many groundwater samples in both season

Hydrogeochemical characterization and groundwater quality assessment in a coal mining area, India

The present study determines major and trace element chemistry of groundwater in the West Bokaro coalfield to assess the hydrogeochemical processes and groundwater quality for drinking and irrigation uses. For this urpose, 33 groundwater samples from different mining areas of the West Bokaro coalfield were collected and analysed for pH, electrical conductivity (EC), total dissolved solid (TDS), dissolved silica (SiO2), major cations (Ca2+, Mg2+, Na+, K+), anions (F−, Cl−, HCO3−, SO42− and NO3−) and trace metals (Mn, Cu, Pb,Zn, Ni, Co, As, Se, Al, Cd, Cr, Ba and Fe). The analytical results show the slightly acidic to alkaline nature of groundwater and dominance of HCO3− and SO42− in anionic and Ca2+ and Na+ in cationic abundance. High SO42− concentrations are attributed to the oxidative weathering of pyrite and gypsum dissolution. Supersaturation condition with respect to dolomite and calcite for most samples may result from the dissolution of gypsum after the water is saturated with respect to the carbonate minerals. The data plot on the Gibbs and Piper diagrams revealed that the groundwater chemistry is mainly controlled by rock weathering with secondary contribution from anthropogenic sources. In a majority of the groundwater samples, alkaline earth metals exceed alkalies and strong acids dominate over weak acid. Ca-Mg-HCO3, Ca-Mg-SO4-Cl and Ca-Mg-SO4 were the dominant hydrogeochemical facies. A comparison of groundwater quality parameters in relation to specified limits for drinking water shows that the concentrations of TDS, SO42−, NO3−, total hardness (TH), Fe and Ni are exceeding the desirable limits in many groundwater samples. Quality assessment for irrigation uses reveal that the groundwater is of good to suitable category. Higher salinity and magnesium hazard values at some sites restrict the suitability of groundwater for irrigation purposes

Effect of serum magnesium, and copper in breast carcinoma patients: A comparative cross sectional study in tertiary care hospital, Madhya Pradesh, India

Background: In our country, there has been little study on breast cancer individuals during and progression of the cancer on magnesium, and copper have not been considered in existing studies. Aim: To determine the effect of serum magnesium, and copper in breast cancer subjects and to compare them with the apparently healthy controls. Methods: Lately diagnosed female subjects with breast cancer in the age group of 40-60 years were included in the study. Apparently healthy controls were selected from the group of people who were attending for annual health check-up and found to be healthy. Results: On comparison between the two groups, the present study observed that serum copper level was lower in case of apparently healthy controls than breast cancer subjects. Comparing between the groups of serum magnesium level, the present study observed significant difference. Similarly, the serum copper level was also found to be significantly differed when compared between the two groups. Conclusion: The altered values of magnesium and copper are responsible for the initiation of breast cancer. In addition, present study implies that serum copper can be used as biomarkers for early identification and diagnosis of breast cancer