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Oxidation Kinetics of L-Arabinose with Quinolinium Chlorochromate

J.V. Singh, Ashish Tomar
2018 Asian Journal of Chemistry  
Oxidation kinetics of L-arabinose with quinolinium chlorochromate (QCC) have been investigated spectrophotometrically. Under pseudofirst order condition, the oxidation is first order with respect to both [QCC] and [L-arabinose]. The oxidation rate was promoted by [acid] and remains unaffected by [NaClO4]. A 1:1 stoichiometry is observed. Activation energy and concerned thermodynamic parameters worked out from reaction rate at different temperatures. Mechanism consistent with the observed data has been proposed.
doi:10.14233/ajchem.2018.21134 fatcat:twkwurbkbbdqjkirr3tynhphxm

Kinetics and mechanism of oxidation of D-fructose by tetraethylammonium chlorochromate in aqueous acetic acid

Ashish Tomar, Arun Kumar
2006 Zenodo  
Department of Chemistry. Meerut College, Meerut-250 001, Uttar Pradesh. India E-mail : Manuscript received 20 April 2006, revised 17 July 2006, accepted 23 August 2006 In an attempt for developing new oxochromium(VI) reagents for effective and selective oxidation of organic substrates under mild conditions we report in the present paper the kinetic and mechanistic study of the oxidation of D-fructose by tetraethylammonium chlorochromate (C2H5)4NCr03CI. The reaction
more » ... s been carried out in aqueous acetic acid 50% (v/v) medium in presence of perchloric acid at constant ionic strength. The reaction has been found to be first-order with respect to each of the oxidant and substrate under pseudo first-order conditions. The reaction is catalysed by acid and follows a first-order dependence on n+ ion concentration. The ionic strength variation has no effect on the reaction rate. The decrease in dielectric constant of the medium increases the rate of reaction. A 1 : 1 stoichiometry is observed in the oxidation and the reaction rate is not retarded by the addition of radical trapping agent acrylonitrile. Effect of temperature on the rate of oxidation has been studied to show the validity of Arrhenius equation and various activation parameters have been computed. The products of oxidation are identified to be D-erythrose and glycollic acid. On the observed facts a hydride ion transfer mechanism is proposed.
doi:10.5281/zenodo.5832934 fatcat:bw4sutrofbd7xe6h2dmmn5olde

Kinetics and mechanism of oxidation of L-sorbose by tetraethylammonium chlorochromate in aqueous acetic acid

Ashish Tomar, Arun Kumar
2007 Zenodo  
Department of Chemistry, Meerut College, Meerut-250 001, Uttar Pradesh, India E-mail : ashishtomar 1983@yahoo. co. in Manuscript received 10 May 2007, revised 8 August 2007, accepted 23 August 2007 The kinetics of oxidation of L-sorbose by tetraethylammonium chlorochromate in aqueous acetic' acid 50% (v/v) medium has been investigated. The reaction has been found to be first order with respect to each of the [oxidant] and [substrate] under pseudo-first order conditions. The reaction is
more » ... by acid and a medium of low dielectric constant favors the oxidation reaction. The ionic strength variation does not influence the reaction rate. A 1 : 1 stoichiometry is observed in the oxidation and the reaction rate is not retarded by radical trapping agent, acrylonitrile. The erythrose and glycolic acid have been identified as main products of the oxidation. The effect of temperature is studied and activation parameters are determined. On the basis of kinetic results, a hydride ion transfer mechanism is proposed.
doi:10.5281/zenodo.5824740 fatcat:vjjxtdjjgffvjfw4jq4geedbpy

Affected energy metabolism under manganese stress governs cellular toxicity

Gursharan Kaur, Vineet Kumar, Amit Arora, Ajay Tomar, Ashish, Runa Sur, Dipak Dutta
2017 Scientific Reports  
Excessive manganese exposure is toxic, but a comprehensive biochemical picture of this assault is poorly understood. Whether oxidative stress or reduced energy metabolism under manganese exposure causes toxicity is still a debate. To address this, we chose ΔmntP Escherichia coli, a highly manganesesensitive strain, in this study. Combining microarray, proteomics, and biochemical analyses, we show that the chronic manganese exposure rewires diverse regulatory and metabolic pathways. Manganese
more » ... ess affects protein and other macromolecular stability, and envelope biogenesis. Most importantly, manganese exposure disrupts both iron-sulfur cluster and heme-enzyme biogenesis by depleting cellular iron level. Therefore, the compromised function of the iron-dependent enzymes in the tricarboxylic acid cycle, and electron transport chain impede ATP synthesis, leading to severe energy deficiency. Manganese stress also evokes reactive oxygen species, inducing oxidative stress. However, suppressing oxidative stress does not improve oxidative phosphorylation and cell growth. On the contrary, iron supplementation resumed cell growth stimulating oxidative phosphorylation. Therefore, we hypothesize that affected energy metabolism is the primal cause of manganese toxicity. Published: xx xx xxxx OPEN 2 Scientific RepoRts | 7: 11645 |
doi:10.1038/s41598-017-12004-3 pmid:28928443 pmcid:PMC5605510 fatcat:cdbgwpdzo5en5hdvmzarslhlta

Simulation of a Smart Sensor Detection Scheme for Wireless Communication Based on Modeling

Hakan Koyuncu, Ashish Bagwari, Geetam Singh Tomar
2020 Electronics  
The principle of sensing and sending information applies to all kinds of communications in different media like air, water, etc. During data transmission through sensors, the most important issue is sensing failure problems. In communication systems, sensing failure problems generally occur and affect sensor system performance. In this study, sensing failure issues are discussed, and a smart sensor is introduced that detects the communication signals. The characteristics of these sensors are
more » ... ntified with signal-to-noise ratio (SNR) readings. The proposed sensor system has high performance and it is better than many systems in the literature. Graphical findings show that the suggested scheme increases device efficiency and has more performance than the energy detector (ED) and ED-ADT-2013 by 33.5%, adaptive spectrum sensing (ASS)-2012 by 41.5%, energy detecting technique for adaptive spectrum sensing (EDT-ASS)-2015 by 28.2%, energy detector, and cyclo-2010 by 57.0%, and energy-SNR adaptive threshold (ADT) detector-2016 by 52.8% at −12 dB SNR, respectively. The proposed sensor detection scheme performs well compared to other existing sensors regarding sensing time. It was found that cooperative spectrum sensing (CSS) with the proposed method outperforms HwQ-2012 and CSS-EDT-ASS-2015 by 22.70% and 16.10% in terms of probability at −12 dB SNR, respectively, and detects the signal at −19.70 dB SNR.
doi:10.3390/electronics9091506 fatcat:ld4ohqjjavb4jmxgf27w5z62he

Utility of physical examination and comparison to echocardiography for cardiac diagnosis

Ashish Patel, Nitin Singh Tomar, Anil Bharani
2017 Indian Heart Journal  
doi:10.1016/j.ihj.2016.07.020 pmid:28460759 pmcid:PMC5414939 fatcat:6bexg7tq6zb3ribl34vhswdrxa

Multiple Energy Detectors based Spectrum Sensing for Cognitive Radio Networks

Ashish Bagwari, Geetam Singh Tomar
2013 International Journal of Computer Applications  
Cognitive radio is an enabling technology to solve the spectrum scarcity problem in wireless communication. This is based on the concept of opportunistic spectrum access. Spectrum sensing is one of the most important functions in cognitive radio (CR) implementation. In this paper, we propose a multiple energy detectors (MEDs) based scheme with improved detection performance at low signal to noise ratio (SNR). We consider a framework of CR networks in which each CR node is equipped with MEDs and
more » ... each energy detector with single antenna. An analytical model is developed for performance evaluation in terms of probability of false alarm P f , and probability of detection P d . Numerical results obtained in Rayleigh fading channel show that the proposed scheme performs better as compared to conventional energy detector (ED). The proposed scheme is further extended for cooperative detection, which further yield better detection performance. Optimal number of CR users involved in cooperative spectrum sensing is also investigated to reduce overheads and system complexity.
doi:10.5120/10067-4666 fatcat:ga7e6gxfgbcnli76aqvnj4j5n4

Rapid sequence induction with fibrescope: An uncommon practice!

Gaurav Tomar, Indu Kapoor, Ashish Bindra, Charu Mahajan
2016 Journal of Neuroanaesthesiology and Critical Care  
Tomar, Indu Kapoor, Ashish Bindra, Charu Mahajan We report a case of a 32-year-old male patient with high cervical vertebra (C1, C2) body fracture with canal compromise following road traffic accident.  ... 
doi:10.4103/2348-0548.173245 fatcat:hn6b5jotijgk5aprypxdrqu3xy

Post Caesarean Sagittal Sinus Thrombosis after Spinal Anaesthesia: A Case Report

Gaurav Tomar, Neeraj Narang, TC Kriplani, Ashish Sethi
2010 The Indian Anaesthetists' Forum  
Figure 1 :Figure 2 :Figure 3 :Image 2 Figure 4 : 12324 CT Head MRI MRI MRV Image Tomar G, Narang N, Kriplani TC, Sethi A: Post Caesarean Sagittal Sinus Thrombosis after Spinal Anaesthesia:A Case Report  ...  mainly the factor V Leiden mutation (15-17% of cases) and the prothrombin-gene-mutation 20210GA (10-12% of cases), whereas antithrombin III, protein C-and protein S-deficiency are found in only 2-6% of Tomar  ... 
doaj:fa78d1ae8e254c9e9f9d24b1dae837e1 fatcat:v6zqta6r4jgqzckf37z6kkw2fm

Kinetics of Oxidation of D-Galactose by Pyridinium Chlorochromate

2012 Oriental Journal of Chemistry  
The oxidation kinetics of D-Galactose with pyridinium chlorochromate (PCC), have been studied in presence of perchloric acid. The reaction under pseudo-first order condition, is first order with respect to both the oxidant and the substrate. The reaction is markedly catalysed by H + ions and the effect of [NaClO 4 ] is negligible. A 1:1 stoichiometry is observed. Activation parameters have been computed by measuring the rates at different temperatures. A probable mechanism of the reaction is suggested.
doi:10.13005/ojc/280340 fatcat:dhnganps7be4zd7trcafc5uugu

Kinetics and Mechanism of Oxidation of Reducing Sugars: A Review

J.V. Singh, Anupam Awasthi, Dipti, Ashish Tomar, Devendra Singh
2013 Asian Journal of Chemistry  
This review summaries the kinetic and mechanistic aspects of the oxidation reaction of reducing sugars with various oxidants, with emphasis to the Cr(VI) oxidation of reducing sugars. An attempt has been made to cover the recent literature available on oxidation kinetics of reducing sugars upto June 2011.
doi:10.14233/ajchem.2013.13111 fatcat:nksj4uokmfh2tcvl7zscnblxcq

Multiple Energy detectors Based Cognitive Radio Networks Using Adaptive Double-Threshold scheme

Ashish Bagwari, Geetam Singh Tomar
2013 International Journal of Smart Business and Technology  
Bagwari and Geetam Singh Tomar  ...  , -10 dB, -12 dB Probability of Detection Vs Threshold values at SNR = -4 dB, -6 dB, -8 dB, -10 dB, -12 dB, N r = 2 with N = 1000, QPSK modulation scheme and Rayleigh fading channel Jun Hee Lee, Ashish  ... 
doi:10.21742/ijsbt.2013.1.1.02 fatcat:qu7gcwicsnf37napagoidsr2tq

Analytics for Power Grid Distribution Reliability in New York City

Cynthia Rudin, Şeyda Ertekin, Rebecca Passonneau, Axinia Radeva, Ashish Tomar, Boyi Xie, Stanley Lewis, Mark Riddle, Debbie Pangsrivinij, Tyler McCormick
2014 Interfaces  
We summarize the first major effort to use analytics for preemptive maintenance and repair of an electrical distribution network. This is a large-scale multi-year effort between scientists and students at Columbia and MIT and engineers from Con Edison, which operates the world's oldest and largest underground electrical system. Con Edison's preemptive maintenance programs are less than a decade old, and are made more effective with the use of analytics developing alongside the maintenance
more » ... ms themselves. Some of the data used for our projects are historical records dating as far back as the 1880's, and some of the data are free text documents typed by dispatchers. The operational goals of this work are to assist with Con Edison's preemptive inspection and repair program, and its vented cover replacement program. This has a continuing impact on public safety, operating costs, and reliability of electrical service in New York City.
doi:10.1287/inte.2014.0748 fatcat:levz3n5i7fe3lnb2m74c6ye4a4

Enriched the Spectrum Sensing Performance of Estimated SNR based Detector in Cognitive Radio Networks

Ashish Bagwari, Geetam Singh Tomar
2015 International Journal of Hybrid Information Technology  
Ashish Bagwari (Member IEEE, and Member IETE) received the B.Tech. and M.Tech. Degrees in Electronics and communication engineering with Honor's in 2007 and 2011 (Gold Medalist) respectively.  ... 
doi:10.14257/ijhit.2015.8.9.15 fatcat:dzxjmu3ogjak5gcekhhtd3e7mi

Prevalence of symptoms of occupational lung diseases in marble cutting workers

Ashish Shrivastava, Shashi P. Tomar, Mohit Patel
2018 International Journal of Community Medicine and Public Health  
Occupational lung diseases occurs in the workers exposed to occupation related hazards. These include Asthma, COPD, Coal worker pneumoconiosis, Silicosis and Asbestosis. Marble cutting exposes workers to fine dust that can cause a number of pulmonary diseases. Usually these are people from rural areas and they are unaware of health hazards related to occupation. Spreading awareness is the key amongst these people. The objective of the To study the prevalence of symptoms related to occupational
more » ... ung diseases in marble cutting workers, to estimate current status of preventive measures used and to assess adaptive changes after educational interventionsMethods: A cross-sectional study was done on the marble cutting workers of Bhedaghat who were exposed to dust from marble cutting. A survey of their working environment and level of awareness was done using questionnaires. The workers were questioned about their working environment, usage of local preventive measures and health related problems. They were then taught about occupational hazards and preventive techniques that can be adopted to prevent such hazards. In subsequent visits, again a survey was done on how many of them were using adaptive measures and relevant counselling was done.Results: Most common reported respiratory problem was shortness of breath 26% and utilization of preventive measures was very poor only 5% but After the 2 follow-up visits including interventional measures and health education, the percentage of workers who started using preventive measures increased from 5% to 57.77%.Conclusions: Prevention is the key to occupational lung diseases. Early diagnosis and treatment also play a major role as prolonged exposure to these risk factors may cause irreversible damage. Health education, periodic health checkups and use to protective measures are the essence in preventing occupational lung diseases.
doi:10.18203/2394-6040.ijcmph20183063 fatcat:5spa4xjcprafvff225zhpq2jli
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