1
|
Jayaprakash A, KeziSelvaVijila C. Feature selection using Ant Colony Optimization (ACO) and Road Sign Detection and Recognition (RSDR) system. COGN SYST RES 2019. [DOI: 10.1016/j.cogsys.2019.04.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
2
|
Milošević I, Rtimi S, Jayaprakash A, van Driel B, Greenwood B, Aimable A, Senna M, Bowen P. Synthesis and characterization of fluorinated anatase nanoparticles and subsequent N-doping for efficient visible light activated photocatalysis. Colloids Surf B Biointerfaces 2018; 171:445-450. [DOI: 10.1016/j.colsurfb.2018.07.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/22/2018] [Accepted: 07/16/2018] [Indexed: 10/28/2022]
|
3
|
Milosevic I, Jayaprakash A, Greenwood B, van Driel B, Rtimi S, Bowen P. Synergistic Effect of Fluorinated and N Doped TiO₂ Nanoparticles Leading to Different Microstructure and Enhanced Photocatalytic Bacterial Inactivation. Nanomaterials (Basel) 2017; 7:nano7110391. [PMID: 29140308 PMCID: PMC5707608 DOI: 10.3390/nano7110391] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 11/10/2022]
Abstract
This work focuses on the development of a facile and scalable wet milling method followed by heat treatment to prepare fluorinated and/or N-doped TiO2 nanopowders with improved photocatalytic properties under visible light. The structural and electronic properties of doped particles were investigated by various techniques. The successful doping of TiO2 was confirmed by X-ray photoelectron spectroscopy (XPS), and the atoms appeared to be mainly located in interstitial positions for N whereas the fluorination is located at the TiO2 surface. The formation of intragap states was found to be responsible for the band gap narrowing leading to the faster bacterial inactivation dynamics observed for the fluorinated and N doped TiO2 particles compared to N-doped TiO2. This was attributed to a synergistic effect. The results presented in this study confirmed the suitability of the preparation approach for the large-scale production of cost-efficient doped TiO2 for effective bacterial inactivation.
Collapse
Affiliation(s)
- Irena Milosevic
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
| | - Amarnath Jayaprakash
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
| | - Brigitte Greenwood
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
| | - Birgit van Driel
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
| | - Sami Rtimi
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
- Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-GPAO, Station 6, CH-1015 Lausanne, Switzerland.
| | - Paul Bowen
- Ecole Polytechnique Fédérale de Lausanne, EPFL-STI-IMX-LTP, Station 12, CH-1015 Lausanne, Switzerland.
| |
Collapse
|
4
|
Reddy R, Ramachandran B, Rajendran S, Dhavale V, Vardhan H, Hedne N, Kekatpure V, Jayaprakash A, Suresh A, Kuriakose M. Pathway based adaptive therapy in head and neck cancer. Eur J Cancer 2016. [DOI: 10.1016/s0959-8049(16)61706-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
5
|
von Moos N, Koman VB, Santschi C, Martin OJF, Maurizi L, Jayaprakash A, Bowen P, Slaveykova VI. Pro-oxidant effects of nano-TiO2on Chlamydomonas reinhardtii during short-term exposure. RSC Adv 2016. [DOI: 10.1039/c6ra16639c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
This is the first continuous quantification of abiotic and biotic nano-TiO2– stimulated H2O2revealing that measured extracellular and intracellular pro-oxidant endpoints inC. reinhardtiican differ significantly.
Collapse
Affiliation(s)
- Nadia von Moos
- Environmental Biogeochemistry and Ecotoxicology
- Department F.-A. Forel for Environmental and Aquatic Sciences
- School of Earth and Environmental Science
- University of Geneva
- Uni Carl Vogt
| | - Volodymyr B. Koman
- Nanophotonics and Metrology Laboratory
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Christian Santschi
- Nanophotonics and Metrology Laboratory
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Olivier J. F. Martin
- Nanophotonics and Metrology Laboratory
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland
| | - Lionel Maurizi
- Powder Technology Laboratory
- Institute of Materials
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland; ; Tel: +41 21 69 36902
| | - Amarnath Jayaprakash
- Powder Technology Laboratory
- Institute of Materials
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland; ; Tel: +41 21 69 36902
| | - Paul Bowen
- Powder Technology Laboratory
- Institute of Materials
- Swiss Federal Institute of Technology Lausanne (EPFL)
- CH-1015 Lausanne
- Switzerland; ; Tel: +41 21 69 36902
| | - Vera I. Slaveykova
- Environmental Biogeochemistry and Ecotoxicology
- Department F.-A. Forel for Environmental and Aquatic Sciences
- School of Earth and Environmental Science
- University of Geneva
- Uni Carl Vogt
| |
Collapse
|
6
|
Arjunan V, Jayaprakash A, Carthigayan K, Periandy S, Mohan S. Conformational, structural, vibrational and quantum chemical analysis on 4-aminobenzohydrazide and 4-hydroxybenzohydrazide--a comparative study. Spectrochim Acta A Mol Biomol Spectrosc 2013; 108:100-114. [PMID: 23466320 DOI: 10.1016/j.saa.2013.01.076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 01/29/2013] [Accepted: 01/31/2013] [Indexed: 06/01/2023]
Abstract
Experimental and theoretical quantum chemical studies were carried out on 4-hydroxybenzohydrazide (4HBH) and 4-aminobenzohydrazide (4ABH) using FTIR and FT-Raman spectral data. The structural characteristics and vibrational spectroscopic analysis were carried performed by quantum chemical methods with the hybrid exchange-correlation functional B3LYP using 6-31G(**), 6-311++G(**) and aug-cc-pVDZ basis sets. The most stable conformer of the title compounds have been determined from the analysis of potential energy surface. The stable molecular geometries, electronic and thermodynamic parameters, IR intensities, harmonic vibrational frequencies, depolarisation ratio and Raman intensities have been computed. Molecular electrostatic potential and frontier molecular orbitals were constructed to understand the electronic properties. The potential energy distributions (PEDs) were calculated to explain the mixing of fundamental modes. The theoretical geometrical parameters and the fundamental frequencies were compared with the experimental. The interactions of hydroxy and amino group substitutions on the characteristic vibrations of the ring and hydrazide group have been analysed.
Collapse
Affiliation(s)
- V Arjunan
- Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Puducherry 605 008, India.
| | | | | | | | | |
Collapse
|
7
|
Arjunan V, Jayaprakash A, Santhanam R, Marchewka MK, Mohan S. Electronic structure simulations of 2,6-dimethyl-2,5-heptadien-4-one by FTIR, FT-Raman, NMR, UV–vis, NBO and density functional theory. Molecular Simulation 2013. [DOI: 10.1080/08927022.2012.713106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
8
|
Arjunan V, Jayaprakash A, Santhanam R, Thillai Govindaraja S, Mohan S. Electronic structure investigations of 4-methyl-3-penten-2-one by UV–Visible and NMR spectral studies and natural bond orbital analysis by DFT calculations. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.04.076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
9
|
Jayaprakash A, Arjunan V, Jose SP, Mohan S. Vibrational and electronic investigations, thermodynamic parameters, HOMO and LUMO analysis on crotonaldehyde by ab initio and DFT methods. Spectrochim Acta A Mol Biomol Spectrosc 2011; 83:411-419. [PMID: 21930418 DOI: 10.1016/j.saa.2011.08.054] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 08/18/2011] [Accepted: 08/24/2011] [Indexed: 05/31/2023]
Abstract
The energy, geometrical parameters and vibrational wavenumbers of crotonaldehyde were calculated by using ab initio and B3LYP with 6-31G(d,p) and 6-311G(d,p) basis sets. The FT-IR and FT-Raman spectra for liquid state crotonaldehyde have been recorded in the region 3400-400 cm(-1) and 3400-100 cm(-1), respectively and compared with the theoretical spectrographs constructed from the scaled harmonic vibrational frequencies calculated at HF and DFT levels. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. Detailed interpretations on vibrational modes have been made on the observed and theoretical spectra and PED for each mode was also reported more precisely. HOMO and LUMO energy levels are constructed and the corresponding theoretical frontier energy gaps are calculated to realise the charge transfer occurring in the molecule. The thermodynamic properties of the title compound have been calculated at different temperatures and the results reveals the standard heat capacities (C(0)(p)), standard entropies (S(0)) and standard enthalpy changes (ΔH(0)) increases with rise in temperature.
Collapse
Affiliation(s)
- A Jayaprakash
- Department of Physics, Rajiv Gandhi College of Engineering and Technology, Puducherry, India
| | | | | | | |
Collapse
|
10
|
Ramalingam S, Jayaprakash A, Mohan S, Karabacak M. Vibrational investigation on FT-IR and FT-Raman spectra, IR intensity, Raman activity, peak resemblance, ideal estimation, standard deviation of computed frequencies analyses and electronic structure on 3-methyl-1,2-butadiene using HF and DFT (LSDA/B3LYP/B3PW91) calculations. Spectrochim Acta A Mol Biomol Spectrosc 2011; 82:79-90. [PMID: 21813316 DOI: 10.1016/j.saa.2011.06.075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 06/29/2011] [Accepted: 06/30/2011] [Indexed: 05/31/2023]
Abstract
FT-IR and FT-Raman (4000-100 cm(-1)) spectral measurements of 3-methyl-1,2-butadiene (3M12B) have been attempted in the present work. Ab-initio HF and DFT (LSDA/B3LYP/B3PW91) calculations have been performed giving energies, optimized structures, harmonic vibrational frequencies, IR intensities and Raman activities. Complete vibrational assignments on the observed spectra are made with vibrational frequencies obtained by HF and DFT (LSDA/B3LYP/B3PW91) at 6-31G(d,p) and 6-311G(d,p) basis sets. The results of the calculations have been used to simulate IR and Raman spectra for the molecule that showed good agreement with the observed spectra. The potential energy distribution (PED) corresponding to each of the observed frequencies are calculated which confirms the reliability and precision of the assignment and analysis of the vibrational fundamentals modes. The oscillation of vibrational frequencies of butadiene due to the couple of methyl group is also discussed. A study on the electronic properties such as HOMO and LUMO energies, were performed by time-dependent DFT (TD-DFT) approach. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The thermodynamic properties of the title compound at different temperatures reveal the correlations between standard heat capacities (C) standard entropies (S), and standard enthalpy changes (H).
Collapse
Affiliation(s)
- S Ramalingam
- Department of Physics, A.V.C. College, Mayiladuthurai, Tamilnadu, India.
| | | | | | | |
Collapse
|
11
|
Jayaprakash A, Arjunan V, Mohan S. Vibrational spectroscopic, electronic and quantum chemical investigations on 2,3-hexadiene. Spectrochim Acta A Mol Biomol Spectrosc 2011; 81:620-630. [PMID: 21763179 DOI: 10.1016/j.saa.2011.06.064] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 06/19/2011] [Accepted: 06/23/2011] [Indexed: 05/31/2023]
Abstract
The Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 2,3-hexadiene have been recorded in the regions 3400-400 and 3400-100 cm(-1), respectively. A complete assignment and analysis of the fundamental vibrational modes of the molecule were carried out. The observed fundamental modes have been compared with the harmonic vibrational frequencies computed using HF and DFT (B3LYP, B3PW91) methods by employing 6-31G(d,p) and 6-311++G(d,p) basis sets. The scaled vibrational frequencies are found to coincide with the experimentally observed values. Theoretical infrared and Raman spectra at HF and DFT levels have been constructed and compared with the experimental spectra. A comparative study of computed optimised geometrical parameters, infrared and Raman intensities, thermodynamic values and frequencies obtained by different quantum mechanical methods were presented. Molecular electrostatic potential, total density distribution and frontier orbital energy levels are constructed to understand the electronic properties. The most stable geometry of the compound under investigation has been determined from the potential energy surface scan.
Collapse
Affiliation(s)
- A Jayaprakash
- Department of Physics, Rajiv Gandhi College of Engineering and Technology, Puducherry 607402, India
| | | | | |
Collapse
|
12
|
Jayaprakash A. Investigation on extracellular lipase production by Aspergillus japonicus isolated from the paper nest of Ropalidia marginata. ACTA ACUST UNITED AC 2010. [DOI: 10.17485/ijst/2010/v3i2.7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
13
|
|
14
|
Sundaraganesan N, Meganathan C, Joshua BD, Mani P, Jayaprakash A. Molecular structure and vibrational spectra of 3-chloro-4-fluoro benzonitrile by ab initio HF and density functional method. Spectrochim Acta A Mol Biomol Spectrosc 2008; 71:1134-1139. [PMID: 18448383 DOI: 10.1016/j.saa.2008.03.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 02/23/2008] [Accepted: 03/11/2008] [Indexed: 05/26/2023]
Abstract
In this work, the experimental and theoretical spectra of 3-chloro-4-fluoro benzonitrile (3C4FBN) were studied. The Fourier transform infrared and Fourier transform Raman spectra of 3C4FBN were recorded in the solid phase. The optimized geometry was calculated by HF and B3LYP methods with 6-311++G(d,p) basis set. The harmonic-vibrational frequencies, infrared intensities and Raman scattering activities of the title compound were performed at and HF/B3LYP/6-311++G(d,p) level of theories. The scaled theoretical wave number showed very good agreement with the experimental values. The thermodynamic functions of the title compound was also performed at HF/6-31G(d,p) and B3LYP/6-311++G(d,p) level of theories. A detailed interpretation of the infrared and Raman spectra of 3C4FBN was reported. The theoretical spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed.
Collapse
Affiliation(s)
- N Sundaraganesan
- Department of Physics (Engg.), Annamalai University, Annamalai Nagar 608002, India.
| | | | | | | | | |
Collapse
|
15
|
|
16
|
Jayaprakash A, Creed T, Stewart L, Colton B, Mountford R, Standen G, Probert C. Should we monitor vitamin B12 levels in patients who have had end-ileostomy for inflammatory bowel disease? Int J Colorectal Dis 2004; 19:316-8. [PMID: 14618349 DOI: 10.1007/s00384-003-0556-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/25/2003] [Indexed: 02/04/2023]
Abstract
BACKGROUND AND AIMS We examined whether vitamin B12 levels are low following surgery in those patients who have had end-ileostomy for inflammatory bowel disease. PATIENTS AND METHODS This prospective observational study used the database of a university teaching hospital to identify patients with inflammatory bowel disease with an end-ileostomy constructed more than 30 months previously. Precise diagnosis, disease distribution and details of their surgery were collected from case notes of the 39 eligible patients (18 Crohn's disease, 17 ulcerative colitis, 4 indeterminate colitis). Mean duration since ileostomy formation was 12.53 years. Patients found to be vitamin B12 deficient underwent further investigations to ascertain the cause of their vitamin B12 deficiency (<150 ng/l). RESULTS There was no significant difference between serum vitamin B12 levels in patients with Crohn's disease and those in patients with ulcerative colitis following end ileostomy formation. Two patients (5.1%) were identified as having vitamin B12 deficiency. One of these had had a panproctocolectomy for Crohn's disease, followed by subsequent resection for ileal obstruction and ongoing small intestinal disease. The other had had colectomy for ulcerative colitis, in whom no cause other than the ileostomy was found for the vitamin B12 deficiency. There was no significant correlation between serum vitamin B12 levels and duration of ileostomy overall or in the disease subgroups. CONCLUSION We do not recommend routine screening for vitamin B12 deficiency in this group of patients unless they have undergone additional small bowel resection or have ongoing small bowel inflammation.
Collapse
Affiliation(s)
- A Jayaprakash
- Department of Gastroenterology, Bristol Royal Infirmary, Marlborough Street, Bristol, BS2 8HW, UK.
| | | | | | | | | | | | | |
Collapse
|
17
|
Basnet CP, Jayaprakash A. Heterodera raskii n. sp. (Heteroderidae: Tylenchina), a Cyst Nematode on Grass, from Hyderabad, India. J Nematol 1984; 16:213-216. [PMID: 19294013 PMCID: PMC2618391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Abstract
Heterodera raskii n. sp. is described and illustrated from specimens collected from roots of bulb grass, Cyperus bulbosus, in Hyderabad, India. The new species belongs to the 'goettingiana' group and differs from closely related H. cyperi by the elongate ovoid shaped cysts and females, greater fenestral length, width, vulval slit, and absence of egg sac. The stylet knob shape was round in second-stage juveniles and posteriorly sloping in females and males of H. raskii n. sp., while it was anteriorly directed in second-stage juveniles and spherical in females and males of H. cyperi.
Collapse
|
18
|
Jayaprakash A, Rao YS. Life history and behaviour of the cyst nematode,Heterodera oryzicola Rao and Jayaprakash, 1978 in Rice (Oryza sativa L.). ACTA ACUST UNITED AC 1982. [DOI: 10.1007/bf03185020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|