Breakdown Strength Estimation of Non-Cellulosic Insulating Materials Used in Electrical Power Equipment

Sakshi Singh,Mirza Mohd. Mohsin,Aejaz Masood 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.6

Breakdown of solid insulating materials in power equipment could result in undesired outages and replacements, and maybe due to an increase in electric stress on the material. Therefore, it is necessary to conduct a proper diagnosis of materialsbefore their practical use. In this work, a few inherent properties of different non-cellulosic insulating materials, such asNomex, Teflon, laminated Nomex, glass bonded mica, epoxy resin bonded mica paper, and epoxy resin bonded fiberglass,have been evaluated by performing non-destructive dielectric diagnostic measurements, and an attempt has been made tocorrelate these basic parameters to evaluate the breakdown strength (BDS). An equation has been proposed using a basictheory which defines the correlation between the BDS, dielectric constant, dissipation factor, sample thickness, and volumeresistivity. The results obtained from the equation are also compared with the experimental values. The suggested equationwill be helpful to predict the BDS of any non-cellulosic material without experimentation in the laboratory.

Breakdown Strength Estimation of Non-Cellulosic Insulating Materials Used in Electrical Power Equipment

Singh, Sakshi,Mohsin, Mirza Mohd.,Masood, Aejaz The Korean Institute of Electrical and Electronic 2017 Transactions on Electrical and Electronic Material Vol.18 No.6

Breakdown of solid insulating materials in power equipment could result in undesired outages and replacements, and may be due to an increase in electric stress on the material. Therefore, it is necessary to conduct a proper diagnosis of materials before their practical use. In this work, a few inherent properties of different non-cellulosic insulating materials, such as Nomex, Teflon, laminated Nomex, glass bonded mica, epoxy resin bonded mica paper, and epoxy resin bonded fiberglass, have been evaluated by performing non-destructive dielectric diagnostic measurements, and an attempt has been made to correlate these basic parameters to evaluate the breakdown strength (BDS). An equation has been proposed using a basic theory which defines the correlation between the BDS, dielectric constant, dissipation factor, sample thickness, and volume resistivity. The results obtained from the equation are also compared with the experimental values. The suggested equation will be helpful to predict the BDS of any non-cellulosic material without experimentation in the laboratory.

Synthesis, characterization and electrical studies of solid polymer electrolyte (1-x) PANI-KAg4I5·xAl2O3

Sakshi Singh,Rafiuddin 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.45 No.-

In the present work, polymer composite solid electrolyte comprising of Polyaniline as polymer andKAg4I5 using Al2O3 of different compositions having the formula (1 x) PANI-KAg4I5 xAl2O3, x = 0.0–0.5was prepared by solid state reaction method. The characterization was done by XRD, FTIR, TG-DTA, SEMand impedance spectroscopy. The thermal analysis and XRD confirms the presence of both AgI andKAg2I3 in the samples. The maximum conductivity was seen in the composition x = 0.4, i.e. 1.84 10 2 S cm 1 at 313 K and 1.38 10 1 S cm 1 at 513 K, with an activation energy of 0.14 eV.

A Brief Study on Image Restoration with its Types and Enhancement Model

Sakshi Jadhav,Jamvant Singh Kumare 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.4

Fog removal also called as visibility restoration alludes to different strategies that aim to reduce or remove the debasement which have occurred even as digital image was being acquired. The debasement may be because of different elements like relative object-camera motion, blur because of camera mis-center, relative environmental turbulence and others. This paper exhibits an audit on the diverse strategies to eliminate haze from images caught in a hazy environment to recuperate a superior and improved quality of haze free images. Fog removal likewise recognized as visibility restoration alludes to different systems that expect to diminish or uproot the debasement that have happened while the digital image was being obtained. The debasement may be a because of different reasons alike relative object-camera movement, distortion because of camera mis-center, relative environmental turbulence and others.

Genome‑wide mining of respiratory burst homologs and its expression in response to biotic and abiotic stresses in Triticum aestivum

Sudhir Navathe,Sakshi Singh,Vinay Kumar Singh,Ramesh Chand,Vinod Kumar Mishra,Arun Kumar Joshi 한국유전학회 2019 Genes & Genomics Vol.41 No.9

Background Membrane-bound NADPH oxidases (Nicotinamide adenine ainucleotide phosphate oxidase) also called respiratory burst oxidase homologs (Rboh) play an essential role in ROS production under normal as well as environmental stress conditions in plants. Objective To identify and study respiratory burst homologs (Rboh) from the wheat genome as well as characterize their role in various biological and molecular processes along with expression in response to biotic and abiotic stresses. Methods The Rboh homologs in the wheat genome were predicted based on data processing, alignment of sequences and phylogenetic analysis of sequences in numerous plant species and wheat. The conserved motifs were known followed by domain design study. The 3-D structure prediction and similarity modeling were administered for NADPH enzyme domain. Gene ontology and a functional study were done in addition to expression analysis of Triticum aestivum respiratory burst oxidase (TaRboh) gene family in response to biotic as well as abiotic stress. Results Phylogenetic analysis of Rboh gene family members among seven plant species including wheat, classified the family into four subfamilies. Rboh genes are mainly involved in various biological processes such as Response to oxidative stress, Superoxide anion generation, Hydrogen peroxide biosynthetic process. Among the molecular functions, calcium ion binding, peroxidase activity, oxidoreductase activity, superoxide-generating NADPH oxidase activity are essential. Enzyme annotation of the family and superfamily revealed that it encodes to five structural clusters and coding to enzymes NAD(P)H oxidase ( H2O2-forming) (EC:1.6.3.1), Ferric-chelate reductase (NADH) (EC: 1.16.1.7), Peroxidase (EC: 1.11.1.7), Ribose-phosphate diphosphokinase (EC: 2.7.6.1). The enzymes contain six membrane-spanning domains, two hemes, and conserved motifs associated with NADPH, EF-hand and FAD binding. The outcomes additionally reflect a distinct role of this enzyme in different molecular functions which are responsible for the stress signaling. Further, the transcripts of TaRboh found expressed in various plant parts such as stem, leaves, spike, seed, and roots. We also observed expression of these gene family members under drought/combination of drought + heat and important wheat pathogens such as Puccinia striformis, Blumeria graminis f.sp. tritici, Fusarium graminiarum, F. pseudograminiarum, and Zymoseptoria tritici. Conclusions The investigation demonstrated that identified respiratory burst homologs (Rboh) in T. aestivum were involved in pathogen activated ROS production and have regulatory functions in cell death and defense responses.

Study of Serum Adipocytokines and Their Association with Insulin Sensitivity in Morbidly Obese Individuals Undergoing Bariatric Surgery

Astha Sachan,Archna Singh,Sakshi Shukla,Sandeep Aggarwal,Ishfaq Mir,Rakhee Yadav 대한비만학회 2020 The Korean journal of obesity Vol.29 No.4

Background: Obese adipose tissue secretes a variety of adipocytokines that act as metabolic regulators with complex mechanisms. Our objective was to compare serum concentration of a panel of adipocytokines between obese and non-obese individuals and identify any distinct patterns correlating with insulin sensitivity in obesity. Methods: We designed a cross-sectional study among obese (body mass index [BMI] ≥30 kg/m2, n=62) and non-obese (BMI <25 kg/m2, n=32) individuals to compare circulating levels of the adipokines, such as adiponectin and resistin in conjunction with the measurement of the levels of inflammatory cytokines including C-reactive protein (CRP), interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α using Luminex multiplex immunoassay with drop array technology. Correlations between circulating adipocytokine levels and those of multiple well-established markers of insulin resistance including homeostatic model assessment of insulin resistance (HOMA-IR), homeostatic model assessment of β-cell function (HOMA-β) and quantitative insulin sensitivity check index were also established. Results: CRP, IL-8, MCP-1, and TNF-α levels were higher in obese than non-obese individuals; the CRP and IL-8 differences were statistically significant. CRP correlated significantly with markers of insulin resistance (fasting plasma insulin, HOMA-IR, and QUICKI), and adiponectin correlated with HOMA-β in obese individuals. We divided the group of obese individuals on the basis of HOMA-IR levels into insulin-resistant (IR; HOMA-IR ≥2.5) and insulin-sensitive (IS; HOMA-IR <2.5) groups; and 43 out of 62 participants were IR despite comparable BMIs. An overall proinflammatory profile was compared between IR and IS obese, though the values were higher in IR obese but the difference was not significant. Conclusion: Obesity is associated with a general inflammatory milieu and a crosstalk between adipocytokines and insulin resistance is complex as well as multifactorial.

A Review of the Flashover Performance of High Voltage Insulators Constructed with Modern Insulating Materials

Khatoon, Shabana,Khan, Asfar Ali,Singh, Sakshi The Korean Institute of Electrical and Electronic 2017 Transactions on Electrical and Electronic Material Vol.18 No.5

Pollution flashover of outdoor insulators is a common risk, which affects the safe operation of overhead transmission networks. Early electrical power systems, which feature insulators made from ceramic materials have been used all over the world with good performance. At present, non-ceramic insulators are in common use, as a result of their good electrical as well as mechanical properties. The aim of this paper is to discuss and compare the flashover performance of insulators typically used in power lines, such as, porcelain, ethylene-propylene-diene-monomer (EPDM) rubber, room temperature vulcanized (RTV) and high temperature vulcanized (HTV) coated silicone rubber. The effect of various parameters, including the severity of pollution, ice accumulation, and shade profile, are considered.. From the studies reviewed it was concluded that there is a distinct difference in the flashover voltages of different types of insulators, and the silicone provides the best flashover performance of all insulating materials.

A Review of the Flashover Performance of High Voltage Insulators Constructed with Modern Insulating Materials

Shabana Khatoon,Asfar Ali Khan,Sakshi Singh 한국전기전자재료학회 2017 Transactions on Electrical and Electronic Material Vol.18 No.5

Pollution flashover of outdoor insulators is a common risk, which affects the safe operation of overhead transmission networks. Early electrical power systems, which feature insulators made from ceramic materials have been used all over the world with good performance. At present, non-ceramic insulators are in common use, as a result of their good electrical as well as mechanical properties. The aim of this paper is to discuss and compare the flashover performance of insulators typically used in power lines, such as, porcelain, ethylene-propylene-diene-monomer (EPDM) rubber, room temperature vulcanized (RTV) and high temperature vulcanized (HTV) coated silicone rubber. The effect of various parameters, including the severity of pollution, ice accumulation, and shade profile, are considered.. From the studies reviewed it was concluded that there is a distinct difference in the flashover voltages of different types of insulators, and the silicone provides the best flashover performance of all insulating materials.