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Basiri M, Ghaffari ME, Ruan J, Murugesan V, Kleytman N, Belinsky G, Akhavan A, Lischuk A, Guo L, Klinger K, Mistry PK. Osteonecrosis in Gaucher disease in the era of multiple therapies: Biomarker set for risk stratification from a tertiary referral center. eLife 2023; 12:e87537. [PMID: 37249220 PMCID: PMC10317498 DOI: 10.7554/elife.87537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 05/22/2023] [Indexed: 05/31/2023] Open
Abstract
Background A salutary effect of treatments for Gaucher disease (GD) has been a reduction in the incidence of avascular osteonecrosis (AVN). However, there are reports of AVN in patients receiving enzyme replacement therapy (ERT) , and it is not known whether it is related to individual treatments, GBA genotypes, phenotypes, biomarkers of residual disease activity, or anti-drug antibodies. Prompted by development of AVN in several patients receiving ERT, we aimed to delineate the determinants of AVN in patients receiving ERT or eliglustat substrate reduction therapy (SRT) during 20 years in a tertiary referral center. Methods Longitudinal follow-ups of 155 GD patients between 2001 and 2021 were analyzed for episodes of AVN on therapy, type of therapy, GBA1 genotype, spleen status, biomarkers, and other disease indicators. We applied mixed-effects logistic model to delineate the independent correlates of AVN while receiving treatment. Results The patients received cumulative 1382 years of treatment. There were 16 episodes of AVN in 14 patients, with two episodes, each occurring in two patients. Heteroallelic p.Asn409Ser GD1 patients were 10 times (95% CI, 1.5-67.2) more likely than p.Asn409Ser homozygous patients to develop osteonecrosis during treatment. History of AVN prior to treatment initiation was associated with 4.8-fold increased risk of AVN on treatment (95% CI, 1.5-15.2). The risk of AVN among patients receiving velaglucerase ERT was 4.68 times higher compared to patients receiving imiglucerase ERT (95% CI, 1.67-13). No patient receiving eliglustat SRT suffered AVN. There was a significant correlation between GlcSph levels and AVN. Together, these biomarkers reliably predicted risk of AVN during therapy (ROC AUC 0.894, p<0.001). Conclusions There is a low, but significant risk of AVN in GD in the era of ERT/SRT. We found that increased risk of AVN was related to GBA genotype, history of AVN prior to treatment initiation, residual serum GlcSph level, and the type of ERT. No patient receiving SRT developed AVN. These findings exemplify a new approach to biomarker applications in a rare inborn error of metabolism to evaluate clinical outcomes in comprehensively followed patients and will aid identification of GD patients at higher risk of AVN who will benefit from closer monitoring and treatment optimization. Funding LSD Training Fellowship from Sanofi to MB.
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Affiliation(s)
- Mohsen Basiri
- Department of Internal Medicine, Yale UniversityNew HavenUnited States
| | - Mohammad E Ghaffari
- Department of ENT, Head and Neck Surgery, Guilan University of Medical SciencesRashtIslamic Republic of Iran
| | - Jiapeng Ruan
- Department of Internal Medicine, Yale UniversityNew HavenUnited States
| | | | | | - Glenn Belinsky
- Department of Internal Medicine, Yale UniversityNew HavenUnited States
| | - Amir Akhavan
- Department of Computer and Information Science, University of Massachusetts DartmouthDartmoutUnited States
| | - Andrew Lischuk
- Department of Radiology and Biomedical Imaging, Yale UniversityNew HavenUnited States
| | - Lilu Guo
- Translational Sciences, SanofiFraminghamUnited States
| | | | - Pramod K Mistry
- Department of Internal Medicine, Yale UniversityNew HavenUnited States
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V S J, Shaji S, Natarajan G, Sulthan Alavudeen S, Balasubramanian C, Senthilkumaran G, Rajarathinam V, Devaraju P, Murugesan V. POS-100 AN UNUSUAL SITE FOR A COMMON DISEASE IN A RENAL TRANSPLANT RECIPIENT. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.07.118] [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: 11/28/2022] Open
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Rajarathinam V, Gopalakrishnan N, Senthilkumaran G, Vs J, Murugesan V, Balasubramanian C, Devaraju P, Thanigachalam D, Solomon D, Moses Lamech T, Palaniselvam S. POS-021 COVID VACCINE ASSOCIATED GLOMERULAR DISEASES- A CASE SERIES. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.07.036] [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: 10/14/2022] Open
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Venkatachalam N, Palanichamy M, Arabindoo B, Murugesan V. Retraction notice to Enhanced photocatalytic degradation of 4-chlorophenol by Zr4+ doped nano TiO2 Journal of Molecular Catalysis A: Chemical Volume 266, Issues 1–2, 2 April 2007, Pages 158-165. Molecular Catalysis 2022. [DOI: 10.1016/j.mcat.2022.112616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Balasubramanian C, Natarajan G, Senthilkumaran G, Devaraju P, Murugesan V, Vs J, Rajarathinam V, Lamech T, Thanikachalam D, Kamalakannan G, Shaji S, Kannan B, Rajendran M, Rajendran P. POS-102 INCIDENCE, MICROBIOLOGICAL SPECTRUM AND OUTCOME OF ACUTE PERITONITIS IN CONTINUOUS AMBULATORY PERITONEAL DIALYSIS PATIENTS. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.07.120] [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: 11/30/2022] Open
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Devaraju P, Murugesan V, Vs J, Balasubramanian C, Senthilkumaran G, Rajarathinam V, Natarajan G, Rajendran P, Dakshinamoorthy S, Jeyachandran D, Thanikachalam D, Arumugam V, Rajendiran A, Durai R, Solomon D. POS-101 A STUDY ON BACTERIAL INFECTIONS IN KIDNEY TRANSPLANT RECIPIENTS. Kidney Int Rep 2022. [DOI: 10.1016/j.ekir.2022.07.119] [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: 11/30/2022] Open
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Kouwenhoven K, Elwakil I, Wingerden JV, Murugesan V, Thoen DJ, Baselmans JJA, Visser PJD. Model and Measurements of an Optical Stack for Broadband Visible to Near-Infrared Absorption in TiN MKIDs. J Low Temp Phys 2022; 209:1249-1257. [PMID: 36467123 PMCID: PMC9712414 DOI: 10.1007/s10909-022-02774-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 06/17/2022] [Indexed: 06/17/2023]
Abstract
Typical materials for optical Microwave Kinetic Inductance Detetectors (MKIDs) are metals with a natural absorption of ∼ 30-50% in the visible and near-infrared. To reach high absorption efficiencies (90-100%) the KID must be embedded in an optical stack. We show an optical stack design for a 60 nm TiN film. The optical stack is modeled as sections of transmission lines, where the parameters for each section are related to the optical properties of each layer. We derive the complex permittivity of the TiN film from a spectral ellipsometry measurement. The designed optical stack is optimised for broadband absorption and consists of, from top (illumination side) to bottom: 85 nm SiO2, 60 nm TiN, 23 nm of SiO2, and a 100 nm thick Al mirror. We show the modeled absorption and reflection of this stack, which has >80% absorption from 400 to 1550 nm and near-unity absorption for 500-800 nm. We measure transmission and reflection of this stack with a commercial spectrophotometer. The results are in good agreement with the model.
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Affiliation(s)
- K. Kouwenhoven
- SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
- Department of Microelectronics, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
| | - I. Elwakil
- SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - J. van Wingerden
- Else Kooi Laboratory, Delft University of Technology, Feldmannweg 17, 2628 CT Delft, The Netherlands
| | - V. Murugesan
- SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
| | - D. J. Thoen
- Department of Microelectronics, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
- Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - J. J. A. Baselmans
- SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
- Department of Microelectronics, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
| | - P. J. de Visser
- SRON Netherlands Institute for Space Research, Niels Bohrweg 4, 2333 CA Leiden, The Netherlands
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Murugesan V, Amarnath DJ, Shanmugam P. Investigation on Water Hyacinth in Anaerobic Co-Digestion for Biogas Production: A measure to Reduce Kosavampatti and Phoosur Lake Municipal Solid Waste Loading. Nat Env Poll Tech 2022. [DOI: 10.46488/nept.2022.v21i01.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The main aim of this study was to evaluate the lab scale, microbe-enhanced biogas production from water hyacinth blended with poultry waste and cow dung. A mesophilic anaerobic two-stage continuous reactor was set up to study the co-digestion for enhanced biogas production. The optimized mixing ratio of cow dung, water hyacinth, and poultry litter (2:1:1; 4:3:1 and 5:2:1) was used along with the effective microbial solution in a two-stage continuous reactor. The biogas yield was maximum in the 2:1:1 blend than the blends with a mixing ratio of 4:3:1 and 5:2:1. The reactor-loading rate was 4 and 5 g.L-1.day-1 with a retention time of 30 and 60 days respectively. The two-stage anaerobic digestion helps in controlling toxicity by acidogenesis and enhances energy production, thereby proving to be a technology that prevents environmental deterioration and enhances energy recovery, both of which are twin issues that need scientific attention. Maximum specific biogas of 0.128 Nm.L.g-1 of Volatile solid reduction (VSR) in hydrolyzer and 0.205 Nm.L.g-1 of VSR in methanizer was obtained at an optimized Carbon/Nitrogen (C/N) ratio of 20.8. The co-digestion of protein-rich waste with a carbon-rich source offers a reduced acclimatization period in the hydrolyzer with an increased C/N ratio, thereby increasing the biogas yield as observed in the methanizer. Several other parameters including Ammonia level, Volatile Fatty Acids influenced by the reactor alkalinity also determine the biogas yield. With increased alkalinity, free ammonia increases and may be inhibitory for anaerobic fermentation and may be toxic for methanogenic bacteria, thereby contributing to the reduction in biogas yield. The present investigation has led to a novel biogas and power-producing clean development mechanism (CDM) for the first time from a heterogeneous mixture of animal excreta and plant waste (livestock droppings, cow dung, and water hyacinths). The waste samples have been collected from sewage and sullage polluted Kosavampatti Lake and Phoosur lake in Namakkal district of Tamilnadu, India therein ending up in a high quantity of CO2 mitigation.
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Somasundaram K, Thoppalan B, Chellaiah V, Kumar RPS, Murugesan V, Thirumavalavan S. Clinical characteristics and immunosuppression management in kidney transplant recipients infected with severe acute respiratory syndrome coronavirus 2 infection - An observational study. Indian J Transplant 2022. [DOI: 10.4103/ijot.ijot_68_21] [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: 11/04/2022] Open
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Kleytman N, Ruan J, Ruan A, Zhang B, Murugesan V, Lin H, Guo L, Klinger K, Mistry PK. Incremental biomarker and clinical outcomes after switch from enzyme therapy to eliglustat substrate reduction therapy in Gaucher disease. Mol Genet Metab Rep 2021; 29:100798. [PMID: 34485083 PMCID: PMC8408524 DOI: 10.1016/j.ymgmr.2021.100798] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 11/28/2022] Open
Abstract
In Gaucher disease (GD), genetic deficiency of acid β-glucosidase leads to accumulation of its substrate glucosylceramide (GlcCer) and glucosylsphingosine (GlcSph). Lipid-laden cells, most prominently seen as macrophages engorged with GlcCer and GlcSph-laden lysosomes, trigger chronic metabolic inflammation and multisystemic phenotypes. Among the pleiotropic effects of inflammatory cascades, the induction of glucosylceramide synthase accentuates the primary metabolic defect. First-line therapies for adults with GD type 1 include Enzyme Replacement Therapy (ERT) and eliglustat Substrate Reduction Therapy (SRT). The ENCORE phase 3 clinical trial of eliglustat demonstrated non-inferiority compared to ERT. It is not known whether switching stable patients from long-term ERT to SRT results in the incremental reversal of the disease phenotype and its surrogate indicators. Herein, we report real-world experience from a single tertiary referral center of 38 adult GD type 1 patients, stable on long-term ERT (mean 13.3 years), who switched to eliglustat SRT (mean 3.1 years). After switch to SRT, there was significant reduction in spleen volume (P = 0.003) while liver volume, which was normal at baseline, remained unchanged. Platelet counts increased significantly (P = 0.026). Concomitantly, there was reduction of three validated biomarkers of Gaucher disease activity: plasma GlcSph decreased from 63.7 ng/ml (95% CI, 37.6-89.8) to 26.1 ng/ml (95% CI, 15.7-36.6) (P < 0.0001); chitotriosidase fell from 1136.6 nmol/ml/h (95% CI, 144.7-2128.6) to 466.9 nmol/ml/h (95% CI, 209.9-723.9) (P = 0.002); and glycoprotein non-metastatic melanoma B (gpNMB) decreased from 59.3 ng/ml (95% CI, 39.7-78.9) to 43.6 ng/ml (95% CI, 30.7-56.6) (P = 0.0006). There were no episodes of avascular necrosis or fractures in patients on SRT. Patients reported favorable experiences of switching from alternate week infusions to oral therapy. Collectively, these results demonstrate that the switch to eliglustat SRT from ERT leads to incremental response, even in stable patients after long-term ERT.
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Affiliation(s)
| | - Jiapeng Ruan
- Yale Internal Medicine: Digestive Diseases, New Haven, CT, USA
| | - Audrey Ruan
- Yale Internal Medicine: Digestive Diseases, New Haven, CT, USA
| | - Bailin Zhang
- Translational Sciences, Sanofi Genzyme, Cambridge, MA, USA
| | | | - Haiqun Lin
- Yale School of Public Health, New Haven, CT, USA
| | - Lilu Guo
- Translational Sciences, Sanofi Genzyme, Cambridge, MA, USA
| | | | - Pramod K Mistry
- Yale Internal Medicine: Digestive Diseases, New Haven, CT, USA
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Lopez D, Sharma A, Murugesan V. Deep Learning Model to predict the outbreak of Dengue in Tamil Nadu based on human mobility. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.948] [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: 11/16/2022] Open
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Abstract
PURPOSE OF REVIEW For 30 years, ultrasound has been investigated as a means to evaluate salivary gland abnormalities in patients with autoimmune disease. We aim to review the test characteristics of ultrasound for diagnosing Sjögren's syndrome, the scoring systems used for this purpose, and the ultrasound similarities and differences between Sjögren's syndrome and some of its potential salivary gland mimics. RECENT FINDINGS Hypo/anechoic glandular lesions are the major ultrasound characteristic found in Sjögren's syndrome. Most studies have reported such ultrasound abnormalities to have a sensitivity and specificity in the range of 65-85% and 85-95%, respectively, as well as a positive likelihood ratio between 4 and 12. However, similar findings can also be seen in sarcoidosis, amyloidosis, IgG4-related disease, HIV, and lymphoma. A "nodal" pattern of involvement or the ultrasound artifact of "through transmission" can help distinguish some of these mimics from Sjogren's syndrome. Ultrasound can substantially influence the diagnosis of Sjögren's syndrome.
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Affiliation(s)
| | | | - Eugene Y Kissin
- Section of Rheumatology, 72 East Concord Str, Evans 501, Boston, MA, 02118, USA.
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Gopalakrishnan N, Rajasekar D, Dhanapriya J, Dineshkumar T, Sakthirajan R, Balasubramaniyan T, Murugesan V. Unusual cause of crystalline nephropathy. Saudi J Kidney Dis Transpl 2019; 29:462-465. [PMID: 29657221 DOI: 10.4103/1319-2442.229280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Adenine phosphoribosyltransferase deficiency is a rare, inherited autosomal recessive disease presenting with 2,8-dihydroxyadenine (DHA) urolithiasis, DHA nephropathy, and chronic kidney disease. The presence of DHA crystals in urine and renal biopsy is pathognomonic of the disease. We report a 23-year-old female with acute renal failure and nephrotic proteinuria. Urinalysis showed reddish brown, round crystals with dark outline, and central spicules consistent with 2,8-DHA crystals. Renal biopsy showed membranous nephropathy and 2,8-DHA nephropathy. Our patient improved with liberal fluid intake, restriction of high adenine content foods, and oral xanthine dehydrogenase inhibitor febuxostat. Early diagnosis and initiation of treatment prevent renal complications.
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Affiliation(s)
- Natarajan Gopalakrishnan
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - Dhanasekaran Rajasekar
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - Jeyachandran Dhanapriya
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - Thanigachalam Dineshkumar
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - Ramanathan Sakthirajan
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - T Balasubramaniyan
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
| | - V Murugesan
- Institute of Nephrology, Rajiv Gandhi Government General Hospital, Madras Medical College, Chennai, Tamil Nadu, India
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Beshlawy AE, Murugesan V, Mistry PK, Eid K. Reversal of life-threatening hepatopulmonary syndrome in Gaucher disease by imiglucerase enzyme replacement therapy. Mol Genet Metab Rep 2019; 20:100490. [PMID: 31309038 PMCID: PMC6606832 DOI: 10.1016/j.ymgmr.2019.100490] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/23/2019] [Indexed: 02/06/2023] Open
Abstract
Advanced liver disease complicated by hepatopulmonary syndrome is a recognized complication of Gaucher disease. Macrophage-targeted, recombinant enzyme replacement therapy is effective in reversing clinical manifestations attributed to the accumulation of glycolipid-laden macrophages but it is not known whether advanced fibrotic features of the disease can be ameliorated. We describe a splenectomized patient with Gaucher disease who developed massive hepatomegaly, cirrhosis of the liver and life-threatening hepatopulmonary syndrome. Treatment with Imiglucerase enzyme replacement therapy resulted in dramatic reversal of hepatopulmonary syndrome and liver disease. Our report suggests that Gaucher disease pathology involving advanced fibrosis and life-threatening complications can be reversed by imiglucerase enzyme therapy. Synopsis Effect of imiglucerase enzyme replacement therapy on Hepatopulmonary Syndrome in Gaucher Disease.
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Affiliation(s)
- Amal El Beshlawy
- Pediatric Hematology, Department of Pediatrics, Cairo University, Egypt
| | - Vagishwari Murugesan
- Department of Internal Medicine, Yale University School of Medicine, United States of America
| | - Pramod Kumar Mistry
- Internal Medicine and Pediatrics, Yale University School of Medicine, 333 Cedar St, LMP 1080, PO Box 208019, New Haven, CT 06520-8019, United States of America
| | - Khaled Eid
- Pediatric Hematology, Department of Pediatrics, Cairo University, Egypt
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Bueno J, Murugesan V, Karatsu K, Thoen DJ, Baselmans JJA. Ultrasensitive Kilo-Pixel Imaging Array of Photon Noise-Limited Kinetic Inductance Detectors Over an Octave of Bandwidth for THz Astronomy. J Low Temp Phys 2018; 193:96-102. [PMID: 30839749 PMCID: PMC6190645 DOI: 10.1007/s10909-018-1962-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 05/10/2018] [Indexed: 06/09/2023]
Abstract
We present the development of a background-limited kilo-pixel imaging array of ultrawide bandwidth kinetic inductance detectors (KIDs) suitable for space-based THz astronomy applications. The array consists of 989 KIDs, in which the radiation is coupled to each KID via a leaky lens antenna, covering the frequency range between 1.4 and 2.8 THz. The single pixel performance is fully characterised using a representative small array in terms of sensitivity, optical efficiency, beam pattern and frequency response, matching very well its expected performance. The kilo-pixel array is characterised electrically, finding a yield larger than 90% and an averaged noise-equivalent power lower than 3 × 10 - 19 W/Hz 1 / 2 . The interaction between the kilo-pixel array and cosmic rays is studied, with an expected dead time lower than 0.6% when operated in an L2 or a similar far-Earth orbit.
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Affiliation(s)
- J. Bueno
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
| | - V. Murugesan
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
| | - K. Karatsu
- Terahertz Sensing Group, Delft University of Technology, Delft, The Netherlands
| | - D. J. Thoen
- Terahertz Sensing Group, Delft University of Technology, Delft, The Netherlands
| | - J. J. A Baselmans
- SRON Netherlands Institute for Space Research, Utrecht, The Netherlands
- Terahertz Sensing Group, Delft University of Technology, Delft, The Netherlands
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Myilsamy M, Mahalakshmi M, Subha N, Murugesan V. Mesoporous Ga-TiO₂: Role of Oxygen Vacancies for the Photocatalytic Degradation Under Visible Light. J Nanosci Nanotechnol 2018; 18:925-935. [PMID: 29448516 DOI: 10.1166/jnn.2018.14207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Gallium doped mesoporous TiO2 with different weight percentages were synthesized by sol-gel method using Pluronic P123 as the structure directing template. The physico-chemical properties of all the synthesized catalysts were determined by XRD, TEM, SEM-EDAX, N2 adsorption-desorption studies, XPS, UV-vis DRS, FT-IR and photoluminescence spectroscopy. 1.0 wt% Ga-TiO2 exhibited the highest photocatalytic efficiency among all the synthesized materials under visible light due to the high surface area, reduced band gap and suppressed electron-hole recombination. Ga3+ ions substitutions for Ti4+ ions in TiO2 lattice created oxygen vacancies in TiO2 lattice, which created a defect energy level below the conduction band of TiO2 and hence the band gap was reduced. The oxygen vacancy defects was playing significant role to improve the adsorption of oxygen molecules, hydroxide ions and cationic rhodamine B (RhB) on TiO2 surface in an aqueous medium. The lifetime of the charge carriers was also enhanced by trapping the photogenerated electrons in oxygen vacancies and transferring them to the adsorbed O2 to produce superoxide anion radicals (O-. 2 ). The photo-induced holes at valence band reduced the adsorbed OH- ions and produced a large number of .OH radicals, which subsequently degraded the RhB. Hence oxygen vacancies created by gallium doping on TiO2 enhanced the photocatalytic efficiency for the degradation of RhB under visible light.
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Affiliation(s)
- M Myilsamy
- Department of Chemistry, SSN College of Engineering, Kalavakkam 603110, Tamilnadu, India
| | - M Mahalakshmi
- Department of Chemistry, SSN College of Engineering, Kalavakkam 603110, Tamilnadu, India
| | - N Subha
- Department of Chemistry, SSN College of Engineering, Kalavakkam 603110, Tamilnadu, India
| | - V Murugesan
- Department of Chemistry, Abdur Rahman University, Chennai 48, Tamilnadu, India
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Subha N, M. M, Myilsamy M, Reddy NL, Shankar M, Neppolian B, Murugesan V. Influence of synthesis conditions on the photocatalytic activity of mesoporous Ni doped SrTiO3/TiO2 heterostructure for H2 production under solar light irradiation. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.03.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Murugesan V, Chuang WL, Liu J, Lischuk A, Kacena K, Lin H, Pastores GM, Yang R, Keutzer J, Zhang K, Mistry PK. Glucosylsphingosine is a key biomarker of Gaucher disease. Am J Hematol 2016; 91:1082-1089. [PMID: 27441734 DOI: 10.1002/ajh.24491] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/14/2016] [Accepted: 07/18/2016] [Indexed: 11/07/2022]
Abstract
Gaucher disease (GD) involves the accumulation of glucosylceramide (GL1) and its deacylated lysolipid, glucosylsphingosine (lyso-GL1) which is implicated in mediating immune dysregulation and skeletal disease. The aim of our study was to assess plasma Lyso-GL1 as a biomarker of GD and its response to therapy. Plasma lyso-GL1 in 169 patients with GD type 1 (GD1) was measured by LC-MS/MS. Significant predictors of plasma LGL1 were assessed by Pearson's correlation coefficient, Wilcoxon Mann Whitney test and multiple linear regression. Propensity scores were used to match patients on treatment mode: Enzyme Replacement Therapy (ERT) vs. Eliglustat Tartrate SRT (ELI-SRT). Plasma Lyso-GL1 levels in healthy controls averaged 1.5 ng/ml (1.3-1.7; 95% CI). In untreated GD patients, the levels were massively elevated (180.9 ng/ml: 95% CI, 145.4-216.5) and imiglucerase ERT resulted in marked reduction (89 ng/ml: 95% CI, 69.2-129.4) (P < 0.001). Lyso-GL1 correlated with chitotriosidase (r = 0.59 P < 0.001), CCL18 (r = 0.62 P <0.001), hepatomegaly (r = 0.28 P < 0.001), splenomegaly (r = 0.27 P = 0.003), splenectomy (P = 0.01) and treatment mode (P < 0.001). By multiple linear regression, the strongest predictors of lyso-GL1 were age (P < 0.001), splenectomy (P = 0.02), Chitotriosidase (P < 0.001) and CCL18 levels (P = 0.001). After propensity score matching to obtain comparable groups of patients on ERT vs ELI-SRT, lyso-GL1 levels were lower among patients receiving ELI-SRT by 113 ng/ml (95% CI: 136-90.3 ng/ml P < 0.001). Plasma lyso-GL1 is a key biomarker of GD. ERT reduced lyso-GL1 levels. By propensity scoring, ELI-SRT resulted in greater reduction of lyso-GL1 than ERT. Am. J. Hematol. 91:1082-1089, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Vagishwari Murugesan
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut
| | | | - Jun Liu
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut
| | - Andrew Lischuk
- Department of Radiology, Yale University School of Medicine, New Haven, Connecticut
| | | | - Haiqun Lin
- Department of Biostatistics, Yale School of Public Health
| | - Gregory M Pastores
- Department of Neurology, New York University School of Medicine, New York
| | - Ruhua Yang
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut
| | | | - Kate Zhang
- Sanofi Genzyme, Framingham, Massachusetts
| | - Pramod K Mistry
- Department of Internal Medicine & Pediatrics, Yale University School of Medicine, New Haven, Connecticut.
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Murugesan V, Lischuk A, Haims A, Lackman R, Brooks JS, Mankin H, Mistry PK. Case series and literature review of skeletal tumors and their incidence in the Gaucher disease population. Am J Hematol 2016; 91:736-41. [PMID: 27102845 DOI: 10.1002/ajh.24398] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/18/2016] [Accepted: 04/19/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Vagishwari Murugesan
- Department of Medicine; Yale University School of Medicine; New Haven Connecticut
| | - Andrew Lischuk
- Department of Radiology; Yale University School of Medicine; New Haven Connecticut
| | - Andrew Haims
- Department of Radiology; Yale University School of Medicine; New Haven Connecticut
| | - Richard Lackman
- Department of Orthopedic Oncology; Cooper University; Camden New Jersey
| | - John S. Brooks
- Department of Pathology and Laboratory Medicine; Perelman School of Medicine, University of Pennsylvania; Philadelphia Pennsylvania
| | - Henry Mankin
- Department of Orthopedic Oncology; Harvard Medical School, Harvard University; Cambridge Massachusetts
| | - Pramod K. Mistry
- Departments of Medicine and Pediatrics; Yale University School of Medicine; New Haven Connecticut
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Endo A, Yates SJC, Bueno J, Thoen DJ, Murugesan V, Baryshev AM, Klapwijk TM, van der Werf PP, Baselmans JJA. Superconducting Coplanar Waveguide Filters for Submillimeter Wave On-Chip Filterbank Spectrometers. J Low Temp Phys 2016; 184:412-417. [PMID: 27340291 PMCID: PMC4880640 DOI: 10.1007/s10909-016-1579-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 03/02/2016] [Indexed: 06/06/2023]
Abstract
We show the first experimental results which prove that superconducting NbTiN coplanar-waveguide resonators can achieve a loaded Q factor in excess of 800 in the 350 GHz band. These resonators can be used as narrow band pass filters for on-chip filter bank spectrometers for astronomy. Moreover, the low-loss coplanar waveguide technology provides an interesting alternative to microstrip lines for constructing large scale submillimeter wave electronics in general.
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Affiliation(s)
- A. Endo
- />Department of Microelectronics, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
- />Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - S. J. C. Yates
- />SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
| | - J. Bueno
- />SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - D. J. Thoen
- />Department of Microelectronics, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
| | - V. Murugesan
- />SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
| | - A. M. Baryshev
- />SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands
- />Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen, The Netherlands
| | - T. M. Klapwijk
- />Kavli Institute of Nanoscience, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
- />Physics Department, Moscow State Pedagogical University, 119991 Moscow, Russia
| | - P. P. van der Werf
- />Leiden Observatory, Leiden University, PO Box 9513, 2300 RA Leiden, The Netherlands
| | - J. J. A. Baselmans
- />Department of Microelectronics, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, Mekelweg 4, 2628 CD Delft, The Netherlands
- />SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands
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Murugesan V, Pulimamidi VK, Rajappa M, Satheesh S, Revathy G, Harichandrakumari KT. Elevated fibrinogen and lowered homocysteine-vitamin determinants and their association with left atrial thrombus in patients with rheumatic mitral stenosis. Br J Biomed Sci 2015; 72:102-6. [PMID: 26510264 DOI: 10.1080/09674845.2015.11666804] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Mitral stenosis (MS) causes stagnation of blood flow, leading to thrombus formation in the left atrium (LA), which may lead to systemic thrombo-embolic complications and stroke. We compared the alterations in echocardiographic and procoagulant parameters in patients with severe rheumatic MS with and without LA thrombus. The study was a cross-sectional study of patients with rheumatic MS, being evaluated for percutaneous mitral commisurotomy. Group 1 patients comprised of patients with rheumatic MS with LA thrombus (n=35) and Group 2 patients had rheumatic MS without LA thrombus (n = 45). Platelet aggregability, fibrinogen, homocysteine, vitamin B12 and folate; mitral valve area (MVA), mean mitral gradient and pulmonary artery pressure (PAP) were assessed in all study subjects. Significant increase in fibrinogen, homocysteine and platelet aggregation and fall in homocysteine-associated determinants were seen in Group 1, as compared with Group 2. Raised fibrinogen, lowered homocysteine-vitamin determinants and lowered mitral valve area were associated independently, with presence of LA thrombus in rheumatic MS. In this study, fibrinogen, vitamin B12 and folate were independently associated with the occurrence of thrombus in patients with rheumatic MS. Hence, our results suggest that increase in procoagulant mechanisms contribute to increased risk of thrombosis in the left atrium in patients with rheumatic MS.
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Myilsamy M, Murugesan V, Mahalakshmi M. The Effect of Synthesis Conditions on Mesoporous Structure and the Photocatalytic Activity of TiO2 Nanoparticles. J Nanosci Nanotechnol 2015; 15:4664-4675. [PMID: 26369095 DOI: 10.1166/jnn.2015.9772] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Mesoporous TiO2 nanoparticles have been synthesized by sol-gel method in different preparation conditions to investigate the effect of triblock copolymer, acetic acid and water on mesoporous structure and the photocatalytic activity. The synthesized photocatalysts were characterized by means of X-ray powder diffraction, Nitrogen adsorption/desorption studies, High resolution transmission electron microscopy, Scanning electron microscopy, Diffuse reflectance UV-Vis spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and thermogravimetric analysis. Among the various synthesized materials, mesoporous TiO2 synthesized using triblock copolymer as a structure directing template in acetic acid medium with high water ratio calcined at 400 degrees C was found to have the highest photocatalytic activity due to the enhanced band gap energy, high specific surface area and high average pore size. The large mesopores provide more pathways for the reactants to enter and products to escape and enhances the adsorption of methylene blue. The photocatalytic activity decreases with increase of solution pH. The rate of *OH formation is high at lower pH, which enhances the photocatalytic activity was revealed by photoluminescence technique. In addition, the adsorbed hydroxyl groups on the surface of mesoporous TiO2 particles can interact with photogenerated holes to produce more *OH radicals, which enhances charge transfer efficiency and enhances the rate of *OH formation.
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Rajani AR, Mahmoud WE, Murugesan V, BinBrek AS. The mystery of recurrent idiopathic cerebrovascular and coronary arterial thrombosis. BMJ Case Rep 2014; 2014:bcr2014205430. [PMID: 25422328 PMCID: PMC4244328 DOI: 10.1136/bcr-2014-205430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2014] [Indexed: 11/03/2022] Open
Abstract
A 46-year-old man presented to our hospital with ST elevation myocardial infarction (STEMI). Previous records revealed a history of recurrent non-STEMI, stroke and transient ischaemic attacks. He was thoroughly investigated with coronary angiography, a cerebral CT angiography, thrombophilia panel and autoimmune screening tests, all of which proved negative. His current episode of STEMI resulted while on dual antiplatelet therapy; the patient was investigated for P2Y12 receptor resistance, which was also negative. A diagnosis of idiopathic recurrent arterial thrombosis was established and the patient was discharged home on aspirin and warfarin. Routine follow-up has revealed no recurrence of symptoms.
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Affiliation(s)
- Ali Raza Rajani
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, UAE
| | - Wael Ezzat Mahmoud
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, UAE
| | | | - Azan Salem BinBrek
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, UAE
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Rajani AR, Murugesan V, Baslaib FO, Rafiq MA. Mitral valve prolapse and electrolyte abnormality: a dangerous combination for ventricular arrhythmias. BMJ Case Rep 2014; 2014:bcr-2014-205055. [PMID: 24827670 DOI: 10.1136/bcr-2014-205055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 27-year-old woman with a history of bileaflet mitral valve prolapse and moderate mitral regurgitation presented to our emergency with untractable polymorphic wide complex tachycardia and unstable haemodynamics. After cardiopulmonary resuscitation, return of spontaneous circulation was achieved 30 min later. Her post-resuscitation ECG showed a prolonged QT interval which progressively normalised over the same day. Her laboratory investigations revealed hypocalcaemia while other electrolytes were within normal limits. A diagnosis of ventricular arrhythmia secondary to structural heart disease further precipitated by hypocalcaemia was made. Further hospital stay did not reveal a recurrence of prolonged QT interval or other arrhythmias except for an episode of non-sustained ventricular tachycardia. However, the patient suffered diffuse hypoxic brain encephalopathy secondary to prolonged cardiopulmonary resuscitation.
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Affiliation(s)
- Ali Raza Rajani
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, United Arab Emirates
| | - Vagishwari Murugesan
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, United Arab Emirates
| | - Fahad Omar Baslaib
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, United Arab Emirates
| | - Muhammad Anwer Rafiq
- Department of Cardiology, Rashid Hospital, Dubai Health Authority, Dubai, United Arab Emirates
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Devika S, Sundaravel B, Palanichamy M, Murugesan V. Vapour phase oxidation of toluene over CeAlPO-5 molecular sieves. J Nanosci Nanotechnol 2014; 14:3187-3192. [PMID: 24734753 DOI: 10.1166/jnn.2014.8571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Single-site CeAlPO-5 with Al/Ce ratios 25, 50, 75, 100 and 125 were synthesized hydrothermally in fluoride medium. The XRD patterns of CeAlPO-5 exhibited characteristic reflections of AlPO-5. 27Al MAS-NMR of CeAIPO-5(25) showed two unusual peaks at -20.78 and -71.35 ppm due to delocalization of cerium unpaired electron. However, 31P MAS-NMR exhibited the usual characteristic peak similar to that of AlPO-5. Vapour phase oxidation of toluene in air over CeAlPO-5 yielded benzaldehyde with high toluene conversion. The time on stream study established the stability of the catalyst. This catalyst can also be used for the selective oxidation of other alkyl aromatics.
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Selvakumar E, Anandha babu G, Ramasamy P, Murugesan V, Chandramohan A. Synthesis, growth and spectroscopic investigation of an organic molecular charge transfer crystal: 8-hydroxy quinolinium 4-nitrobenzoate 4-nitrobenzoic acid. Spectrochim Acta A Mol Biomol Spectrosc 2014; 117:259-263. [PMID: 23995602 DOI: 10.1016/j.saa.2013.07.097] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 07/22/2013] [Accepted: 07/31/2013] [Indexed: 06/02/2023]
Abstract
An organic intermolecular charge transfer complex salt of 8-Hydroxy quinolinium 4-nitrobenzoate 4-nitrobenzoic acid (OPNB) has been synthesized. Single crystals of OPNB were grown by slow solvent evaporation solution growth technique at room temperature. The (1)H and (13)C NMR spectra were recorded to confirm the molecular structure of the complex salt. The crystal structure of OPNB has been determined by single crystal XRD analysis and it belongs to triclinic crystal system with space group P-1. Fourier transform infrared (FT-IR) spectral study has been carried out to identify the various functional groups present. The UV-Vis-NIR transmittance spectrum was recorded in the range 200-2500nm, to find the suitability of the single crystal for various optical applications. The thermal stability of the crystal was investigated using thermogravimetric (TG) and differential thermal analyses (DTA).
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Affiliation(s)
- E Selvakumar
- Postgraduate and Research Department of Chemistry, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020, Tamilnadu, India
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Rawal RK, Murugesan V, Katti SB. Structure-activity relationship studies on clinically relevant HIV-1 NNRTIs. Curr Med Chem 2013; 19:5364-80. [PMID: 22998569 DOI: 10.2174/092986712803833326] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 08/25/2012] [Accepted: 08/29/2012] [Indexed: 11/22/2022]
Abstract
In addition to the nucleoside reverse transcriptase inhibitors (NRTIs), protease inhibitors (PIs) and integrase inhibitors (INIs), nonnucleoside reverse transcriptase inhibitors (NNRTIs) have contributed significantly in the treatment of HIV-1 infections. More than 60 structurally different classes of compounds have been identified as NNRTIs, which are specifically inhibiting HIV-1 reverse transcriptase (RT). Five NNRTIs (nevirapine, delavirdine, efavirenz, etravirine and rilpivirine) have been approved by US Food and Drug Administration (FDA) for clinical use. The NNRTIs bind with a specific 'pocket' site of HIV-1 RT (allosteric site) that is closely associated with the NRTI binding site. Due to mutations of the amino acid residues surrounding the NNRTI-binding site, NNRTIs are notorious for rapidly eliciting resistance. Though, the emergence of resistant HIV strains can be circumvented if the NNRTIs are used either alone or in combination with NRTIs (AZT, 3TC, ddI, ddC, TVD or d4T) and PIs (Indinavir, nelfinavir, saquinavir, ritonavir and lopinavir etc.) as shown by both a decrease in plasma HIV-1 RNA levels and increased CD4 T-cells. Here we are going to discuss recent advances in structure activity relationship studies on nevirapine, delavirdine, efavirenz, etravirine, rilpivirine and 4-thiazolidinones (privileged scaffold) HIV-1 NNRTIs.
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Affiliation(s)
- R K Rawal
- Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow 226001, India
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Palanisamy B, Babu CM, Sundaravel B, Anandan S, Murugesan V. Sol-gel synthesis of mesoporous mixed Fe2O3/TiO2 photocatalyst: application for degradation of 4-chlorophenol. J Hazard Mater 2013; 252-253:233-42. [PMID: 23535564 DOI: 10.1016/j.jhazmat.2013.02.060] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 02/10/2013] [Accepted: 02/28/2013] [Indexed: 05/06/2023]
Abstract
Photosensitization of TiO2 with other transition metal oxides can extend its light absorption property in the visible region. Such materials could emerge as excellent catalysts for solar photocatalytic degradation. In the present study mesoporous Fe2O3/TiO2 (10, 30, 50, 70 and 90 wt% Fe2O3) photocatalysts were synthesized by sol-gel process and characterized using different techniques. The XRD patterns exhibited the presence of mesoporous structure and isomorphic substitution of Fe(3+) in TiO2 at low Fe(3+) loading and Ti(4+) in Fe2O3 at high Fe(3+) loading. The XPS results revealed the presence of Ti(4+) and Fe(3+) in Fe2O3/TiO2 materials. The DRS UV-vis spectra showed a shift in the band gap excitation of TiO2 to longer wavelength, thus illustrating incorporation of Fe(3+) in TiO2. In addition, free TiO2 and Fe2O3 particles were also present. Their photocatalytic activity was tested for the degradation of 4-chlorophenol in aqueous medium using sunlight. The activity of the catalysts followed the order: meso-30 wt% Fe2O3/TiO2>meso-10 wt% Fe2O3/TiO2>meso-50 wt% Fe2O3/TiO2>meso-70 Fe2O3/TiO2>meso-90 wt% Fe2O3/TiO2>meso-Fe2O3>meso-TiO2. This order concluded that mesoporous Fe2O3/TiO2 could be an active catalyst for pollutant degradation, as TiO2 with framework Fe(3+) and photosensitization with free Fe2O3 were involved in the activity.
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Affiliation(s)
- B Palanisamy
- Department of Chemistry, Anna University, Chennai 600 025, India
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Palanisamy B, Babu CM, Sundaravel B, Anandan S, Murugesan V. Visible-light active mesoporous ce incorporated TiO2 for the degradation of 4-chlorophenol in aqueous solution. J Nanosci Nanotechnol 2013; 13:2573-2581. [PMID: 23763131 DOI: 10.1166/jnn.2013.7404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Efficient visible-light active mesoporous Ce incorporated TiO2 nanoparticles have been prepared by sol-gel method using Pluranic P123 as the structure directing agent. Low angle XRD and BET analysis revealed the mesoporous nature of the nanoparticles. The incorporation of Ce4+ into TiO2 and Ti4+ into CeO2 is evident from the slight shift in their respective XRD patterns. XPS results exhibited +4 oxidation state for Ce and Ti ions. UV-DRS analysis of Ce incorporated TiO2 demonstrated red shift in the absorbance spectrum of TiO2, which is mainly due to the formation of Ce impurity states below the conduction band edge of TiO2. The photocatalytic activity of mesoporous Ce incorporated TiO2 nanoparticles has been evaluated in the degradation of 4-chlorophenol in aqueous solution under solar light illumination. Pure mesoporous TiO2 showed poor visible-light activity due to its small absorption of sun light. Mesoporous Ce incorporated TiO2 photocatalysts exhibited the highest photocatalytic activity compared to pristine mesoporous TiO2 and CeO2. The incorporation of Ce4+ in TiO2 played a major role in the enhancement of photocatalytic activity under sun light.
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Affiliation(s)
- B Palanisamy
- Department of Chemistry, Anna University, Chennai 600025, India
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Sundaravel B, Babu CM, Palanisamy B, Palanichamy M, Shanthi K, Murugesan V. Praseodymium incorporated AIPO-5 molecular sieves for aerobic oxidation of ethylbenzene. J Nanosci Nanotechnol 2013; 13:2507-2516. [PMID: 23763124 DOI: 10.1166/jnn.2013.7415] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
PrAlPO-5 with (Al + P)/Pr ratios of 25, 50, 75 and 100 molecular sieves were successfully synthesized by hydrothermal method. These molecular sieves were characterised using XPS, TPD-NH3, ex-situ pyridine adsorbed IR, TPR, TGA, 27Al and 31P MAS-NMR and ESR studies. The incorporation of praseodymium in the framework of AlPO-5 was confirmed by XRD, DRS UV-vis and 27Al and 31P MAS-NMR analysis. ESR spectrum showed the presence of adsorbed oxygen. The nature and strength of acid sites were identified by ex-situ pyridine adsorbed IR and TPD-NH3. The BET surface area was found to be in the range of 238-272 m2 g(-1). The catalytic activity of the molecular sieves was tested for the liquid phase aerobic oxidation of ethylbenzene. Acetophenone was found to be the major product with more than 90% ethylbenzene conversion. ICP-OES analysis revealed the presence of praseodymium intact in the framework of AlPO-5 up to five cycles.
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Affiliation(s)
- B Sundaravel
- Department of Chemistry, Anna University, Chennai 600025, India
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Visuvamithiran P, Sundaravel B, Palanichamy M, Murugesan V. Oxidation of alkyl aromatics over SBA-15 supported cobalt oxide. J Nanosci Nanotechnol 2013; 13:2528-2537. [PMID: 23763126 DOI: 10.1166/jnn.2013.7388] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
SBA-15 supported Co3O4 with different weight percentage have been prepared by wet impregnation method. The prepared catalysts were characterised by XRD, DRUV-vis, FT-IR, N2 adsorption-desorption, TPR, XPS, SEM and TEM. The TPR profile revealed good dispersion of active sites and interaction of Co3O4 on SBA-15 support. The catalytic activity of SBA-15 supported Co3O4 was evolved in liquid phase benzylic oxidation under mild condition using H2O2 as the oxidant. The benzylic oxidation was ascribed by hydrogen abstraction of the C-H bond. The various reaction parameters such as Co3O4 loading, solvent, temperature and reaction time on the catalytic activity were also investigated. The 5 wt% of Co3O4/SBA-15 catalyst was found to exhibit high conversion (-75%) with product selectivity of -87%.
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Babu CM, Palanisamy B, Sundaravel B, Palanichamy M, Murugesan V. A novel magnetic Fe3O4/SiO2 core-shell nanorods for the removal of arsenic. J Nanosci Nanotechnol 2013; 13:2517-2527. [PMID: 23763125 DOI: 10.1166/jnn.2013.7376] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
A novel magnetic Fe3O4 core-shell nanorods (MCSNs) were synthesized by crosslinking amine functionalized Fe3O4@SiO2 core-shell nanoparticles with 1,2-bromochloroethane. These nanorods were then protonated with dilute HCl. The MCSNs nanorods were characterized using FT-IR, N2 adsorption, VSM, SEM and TEM. The surface area of MCSNs nanorods was found to be 335 m2/g, which is higher than bare iron oxide and amine functionalized Fe3O4@SiO2. These nanorods were used simultaneously as ion-exchanger and adsorbent for the removal of arsenic from aqueous solution. It exhibited high adsorption capacity for arsenic. The kinetic study revealed that adsorption equilibrium attained within five min. The adsorbed arsenic on the nanorods were removed by magnetic separation and regenerated by acid treatment. The percentage removal of arsenic was more than 99%. Such nanorods can be used to remove not only arsenic but also other anions from potable water.
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Affiliation(s)
- C M Babu
- Department of Chemistry, Anna University, Chennai 600025, India
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Visuvamithiran P, Shanthi K, Palanichamy M, Murugesan V. Direct synthesis of Mn-Ti-SBA-15 catalyst for the oxidation of ethylbenzene. Catal Sci Technol 2013. [DOI: 10.1039/c3cy00306j] [Citation(s) in RCA: 46] [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: 11/21/2022]
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Kumaresan L, Prabhu A, Palanichamy M, Arumugam E, Murugesan V. Synthesis and characterization of Zr4+, La3+ and Ce3+ doped mesoporous TiO2: evaluation of their photocatalytic activity. J Hazard Mater 2011; 186:1183-1192. [PMID: 21237564 DOI: 10.1016/j.jhazmat.2010.11.124] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 11/28/2010] [Accepted: 11/29/2010] [Indexed: 05/30/2023]
Abstract
Sol-gel method was used to synthesize Zr(4+), La(3+) and Ce(3+) doped mesoporous TiO(2) materials with different weight percentage (0.5, 1.0, 2.0 and 3.0 wt%) using triblock copolymer as the structure directing template in ethanol/water medium. Characterization revealed the isomorphic substitution of Zr(4+) ion into the lattice of TiO(2), and surface binding nature of La(3+) and Ce(3+) ions on mesoporous TiO(2). Microscopic examination confirmed the surface adsorption of foreign ion which could alter the particle morphology. The size of the particles was less than 20 nm. Photocatalytic activity of metal ions doped mesoporous TiO(2) was evaluated using aqueous alachlor as a model pollutant. It was found that 1 wt% Ce(3+) doped mesoporous TiO(2) exhibited higher activity than pure and other metal ions doped mesoporous TiO(2). The change of oxidation state of Ce(3+) is suggested to be the cause for enhanced photocatalytic activity.
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Affiliation(s)
- L Kumaresan
- Department of Chemistry, Anna University, Chennai 600 025, India
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Sivamurugan V, Deepa K, Palanichamy M, Murugesan V. [(L)Proline]2Zn Catalysed Synthesis of 1,5‐Benzodiazepine Derivatives Under Solvent‐Free Condition. SYNTHETIC COMMUN 2011. [DOI: 10.1081/scc-200034752] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- V. Sivamurugan
- a Department of Chemistry , Anna University , Chennai, 600 025, India
| | - K. Deepa
- a Department of Chemistry , Anna University , Chennai, 600 025, India
| | - M. Palanichamy
- a Department of Chemistry , Anna University , Chennai, 600 025, India
| | - V. Murugesan
- a Department of Chemistry , Anna University , Chennai, 600 025, India
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Kumaresan L, Mahalakshmi M, Palanichamy M, Murugesan V. Synthesis, Characterization, and Photocatalytic Activity of Sr2+ Doped TiO2 Nanoplates. Ind Eng Chem Res 2010. [DOI: 10.1021/ie901191z] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- L. Kumaresan
- Department of Chemistry, Anna University, Chennai 600 025, India, and Department of Chemistry, SSN College of Engineering, Kalavakkam 603 110, India
| | - M. Mahalakshmi
- Department of Chemistry, Anna University, Chennai 600 025, India, and Department of Chemistry, SSN College of Engineering, Kalavakkam 603 110, India
| | - M. Palanichamy
- Department of Chemistry, Anna University, Chennai 600 025, India, and Department of Chemistry, SSN College of Engineering, Kalavakkam 603 110, India
| | - V. Murugesan
- Department of Chemistry, Anna University, Chennai 600 025, India, and Department of Chemistry, SSN College of Engineering, Kalavakkam 603 110, India
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Anandan S, Kathiravan K, Murugesan V, Ikuma Y. Anionic (IO3-) non-metal doped TiO2 nanoparticles for the photocatalytic degradation of hazardous pollutant in water. CATAL COMMUN 2009. [DOI: 10.1016/j.catcom.2008.12.054] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Mahalakshmi M, Vishnu Priya S, Arabindoo B, Palanichamy M, Murugesan V. Photocatalytic degradation of aqueous propoxur solution using TiO2 and Hbeta zeolite-supported TiO2. J Hazard Mater 2009; 161:336-343. [PMID: 18455297 DOI: 10.1016/j.jhazmat.2008.03.098] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Revised: 03/21/2008] [Accepted: 03/24/2008] [Indexed: 05/26/2023]
Abstract
Photocatalytic activity of TiO2 and zeolites supported TiO2 were investigated using propoxur as a model pollutant. Hbeta, HY and H-ZSM-5 zeolites were examined as supports for TiO2. Hbeta was chosen as the TiO2 support based on the adsorption capacity of propoxur on these zeolites (Hbeta>HY=H-ZSM-5). TiO2/Hbeta photocatalysts with different wt.% were prepared and characterized by XRD, FT-IR and BET surface area. The progress of photocatalytic degradation of aqueous propoxur solution using TiO2 (Degussa P-25) and TiO2 supported on Hbeta zeolite was monitored using TOC analyzer, HPLC and UV-vis spectrophotometer. The degradation of propoxur was systematically studied by varying the experimental parameters in order to achieve maximum degradation efficiency. The initial rate of degradation with TiO2/Hbeta was higher than with bare TiO2. TOC results revealed that TiO2 requires 600min for complete mineralization of propoxur whereas TiO2/Hbeta requires only 480min. TiO2/Hbeta showed enhanced photodegradation due to its high adsorption capacity on which the pollutant molecules are pooled closely and hence degraded effectively.
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Affiliation(s)
- M Mahalakshmi
- Department of Chemistry, Anna University, Chennai 600025, India
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Anandan S, Vinu A, Mori T, Gokulakrishnan N, Srinivasu P, Murugesan V, Ariga K. Erratum to “Photocatalytic degradation of 2,4,6-trichlorophenol using lanthanum doped ZnO in aqueous suspension” [Catalysis Communications 8 (9) (2007) 1377–1382]. CATAL COMMUN 2008. [DOI: 10.1016/j.catcom.2008.08.003] [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: 11/26/2022] Open
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Sudha S, Venkatachalam K, Vishnu Priya S, Herbert Mabel J, Palanichamy M, Murugesan V. Single step synthesis of coumarin derivatives over Al-MCM-41 and its supported catalysts under solvent-free condition. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.molcata.2008.04.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Affiliation(s)
| | | | - V. Murugesan
- a Department of Chemistry , Anna University , Chennai , 600 025 , INDIA
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Mahalakshmi M, Arabindoo B, Palanichamy M, Murugesan V. Preparation, characterization, and photocatalytic activity of Gd3+ doped TiO2 nanoparticles. J Nanosci Nanotechnol 2007; 7:3277-3285. [PMID: 18019161 DOI: 10.1166/jnn.2007.689] [Citation(s) in RCA: 8] [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] [Indexed: 05/25/2023]
Abstract
TiO2 and Gd3+ doped TiO2 nanoparticles were prepared by sol-gel method and the materials were characterized by XRD, TEM, SEM-EDX, BET, FT-IR, UV-Vis absorption, and Raman spectral analysis. The photocatalytic activity of nano TiO2 and Gd/TiO2 nanoparticles was evaluated using a model pollutant propoxur, a carbamate pesticide, in a batch type UV photoreactor. The results revealed higher photocatalytic activity for Gd/TiO2 nanoparticles than both TiO2 nanoparticles and commercial TiO2 (Degussa P-25). The enhanced photocatalytic activity of Gd/TiO2 relative to TiO2 is attributed to its increased band gap energy as evidenced from the blue shift to shorter wavelength observed in the UV-Vis abso4ption spectra. The recombination rate of photogenerated electron-hole pair decreased due to increase in the band gap, which enhanced the charge transfer efficiency of Gd/TiO2 nanoparticles. Gd3+ with its half filled 7 f subshell facilitated rapid electron transfer at solid-liquid interface by shallowly trapping the electrons. Among the various dopant level of gadolinium, 0.3 wt% Gd/TiO2 nanoparticles showed higher activity than others due to its higher surface area.
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Affiliation(s)
- M Mahalakshmi
- Department of Chemistry, Anna University, Chennai 600025, India
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Mahalakshmi M, Arabindoo B, Palanichamy M, Murugesan V. Photocatalytic degradation of carbofuran using semiconductor oxides. J Hazard Mater 2007; 143:240-5. [PMID: 17045739 DOI: 10.1016/j.jhazmat.2006.09.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Revised: 07/02/2006] [Accepted: 09/06/2006] [Indexed: 05/12/2023]
Abstract
The photocatalytic degradation of carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate) was investigated in an aqueous solution using Degussa P-25 TiO2 and ZnO as photocatalysts. The progress of degradation was monitored using TOC analyzer, HPLC, GC-MS and UV-vis spectrophotometer. The effects of various experimental parameters such as initial concentration of carbofuran, pH of the solution, catalyst loading and light intensity were systematically studied in order to achieve maximum degradation efficiency. The complete mineralization of carbofuran was confirmed by TOC analyzer. The degradation with ZnO showed less efficiency than TiO2. The formation of NO(3)(-) was identified and quantified using HPLC. In addition, four different intermediates formed during the degradation process were also identified and characterized by GC-MS. The mineralization rate was compared with lamps of wavelength 254 and 365 nm under similar conditions. The rate with 254 nm was observed to be very close to that of 365 nm.
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Affiliation(s)
- M Mahalakshmi
- Department of Chemistry, Anna University, Chennai 600 025, India
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Venkatachalam N, Palanichamy M, Arabindoo B, Murugesan V. Enhanced photocatalytic degradation of 4-chlorophenol by Zr4+ doped nano TiO2. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.molcata.2006.10.051] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kumar GS, Vishnuvarthan M, Palanichamy M, Murugesan V. SBA-15 supported HPW: Effective catalytic performance in the alkylation of phenol. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcata.2006.07.050] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Venkatachalam N, Vinu A, Anandan S, Arabindoo B, Murugesan V. Visible light active photocatalytic degradation of bisphenol-A using nitrogen doped TiO2. J Nanosci Nanotechnol 2006; 6:2499-507. [PMID: 17037863 DOI: 10.1166/jnn.2006.531] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nitrogen doped titania was prepared by low temperature sol-gel method using titanium precursor and nitrogen containing bases like triethylamine and tetramethyl ammonium hydroxide compounds. The materials were characterized by XRD, BET, SEM, XPS, DRS-UV, and FT-IR techniques. DRS-UV study substantially indicates shift of the absorption edge of TiO2 to lower energy region. The phase composition, crystallinity, specific surface area, and visible light activity of nitrogen doped titania depend upon the preparation conditions. Photocatalytic degradation of bisphenol-A in aqueous medium was investigated by TiO2 and nitrogen doped TiO2 under visible light irradiation in a batch photocatalytic reactor. The results indicate higher visible light activity for nitrogen doped TiO2 than commercial TiO2 (Degussa P25) for bisphenol-A degradation. The influence of various parameters such as initial concentration of bisphenol-A, catalyst loading and pH was examined for maximum degradation efficiency.
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Affiliation(s)
- N Venkatachalam
- Department of Chemistry, Anna University, Chennai 600 025, India
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Shankar MV, Anandan S, Venkatachalam N, Arabindoo B, Murugesan V. Fine route for an efficient removal of 2,4-dichlorophenoxyacetic acid (2,4-D) by zeolite-supported TiO2. Chemosphere 2006; 63:1014-21. [PMID: 16289243 DOI: 10.1016/j.chemosphere.2005.08.041] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Revised: 08/16/2005] [Accepted: 08/23/2005] [Indexed: 05/05/2023]
Abstract
Zeolites HY, Hbeta and HZSM-5 with different physico-chemical properties were chosen as support for TiO2 to illustrate their adsorption, dispersion and electronic structure in photocatalysis. The extent of TiO2 loading was monitored by XRD and BET surface area measurements. The adsorption capacity of HY zeolite was found to be high and hence chosen for further modification to continue the investigation. Photodegradation kinetics were carried out with 2,4-dichlorophenoxyacetic acid (2,4-D) in aqueous solution. The extent of 2,4-D degradation on TiO2/HY loading revealed the importance of adsorption in photocatalysis. Mineralisation studies on all three zeolites with 1 wt.% TiO2 loading demonstrated the good dispersion properties of TiO2/HY. Its photocatalytic activity was found to be excellent with formulated 2,4-D. Comparison of relative photonic efficiencies demonstrated that supported photocatalysts exhibited higher activity than some of the commercial photocatalysts. The high activity of supported TiO2 is due to synergistic effects of improved adsorption of 2,4-D and efficient delocalisation of photogenerated electrons by zeolite support.
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Affiliation(s)
- M V Shankar
- Department of Chemistry, Anna University, Chennai, Tamil Nadu 600 025, India
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