Browsing by Author "Namrata Singh"

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Arsenic mediated modifications in Bacillus aryabhattai and their biotechnological applications for arsenic bioremediation
(Elsevier Ltd, 2016) Namrata Singh; Sunil Gupta; Naina Marwa; Vivek Pandey; Praveen C. Verma; Sushma Rathaur; Nandita Singh
The present study reports the arsenic (As) tolerance mechanism of bacteria Bacillus aryabhattai (NBRI014). The data explores the intracellular accumulation and volatilization of As from the culture medium after 48 h of exposure to 25,000 mg l−1 arsenate As(V). The study also provides the evidence of presence of ars operon in bacteria, which may have played an important role in reducing As toxicity. Additionally, we found 7 differentially expressed proteins to be up-regulated in bacterial cells upon As exposure which may have role in reducing As toxicity inside bacterial cells. Furthermore, Fourier transform infrared (FTIR) spectroscopic techniques were useful to describe the structural and compositional alterations in bacterial cells after As treatment. It showed the changes in peak positions of the spectrum pattern when NBRI014 was grown in medium containing As, indicating that these functional groups viz. (amino, alkyl halides and hydroxyl) present on bacterial surface, which may be involved in As binding. The above results signify that biotechnological application of the isolate NBRI014 could be helpful in removal of As from polluted sites. © 2016 Elsevier Ltd
Assessing the bioremediation potential of arsenic tolerant bacterial strains in rice rhizosphere interface
(Chinese Academy of Sciences, 2016) Namrata Singh; Shubhi Srivastava; Sushma Rathaur; Nandita Singh
The arsenic tolerant bacterial strains Staphylococcus arlettae (NBRIEAG-6), Staphylococcus sp. (NBRIEAG-8) and Brevibacillus sp. (NBRIEAG-9) were tested for their roles in enhancing plant growth and induction of stress-related enzymes in rice (Oryza sativa L. cv. NDR-359) plants at two different concentrations, 30 and 15 mg/kg of As(V) and As(III), respectively. An experiment was conducted to test the effect of these strains on plant growth promotion and arsenic uptake. We found 30%–40% reduction in total As uptake in bacteria-inoculated plants, with increased plant growth parameters compared to non-inoculated plants. Moreover, the bacteria-inoculated plants showed reduced activity of total glutathione (GSH) and glutathione reductase (GR) compared to their respective controls, which suggests the bacteria-mediated reduction of oxidative stress in plants. Thus, these strains were found to be beneficial in terms of the biochemical and physiological status of the plants under arsenic stress conditions. Furthermore, one-way ANOVA and principal component analysis (PCA) on enzymatic and non-enzymatic assays also revealed clear variations. The results support the distinction between control and treatments in both shoots and roots. Therefore, this study demonstrates the potential of rhizobacteria in alleviating arsenic stress in rice plants. © 2016
Brevundimonas diminuta mediated alleviation of arsenic toxicity and plant growth promotion in Oryza sativa L.
(Academic Press, 2016) Namrata Singh; Naina Marwa; Shashank k. Mishra; Jyoti Mishra; Praveen C. Verma; Sushma Rathaur; Nandita Singh
Arsenic (As), a toxic metalloid adversely affects plant growth in polluted areas. In the present study, we investigated the possibility of improving phytostablization of arsenic through application of new isolated strain Brevundimonas diminuta (NBRI012) in rice plant [Oryza sativa (L.) Var. Sarju 52] at two different concentrations [10 ppm (low toxic) and 50 ppm (high toxic)] of As. The plant growth promoting traits of bacterial strains revealed the inherent ability of siderophores, phosphate solubilisation, indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase production which may be associated with increased biomass, chlorophyll and MDA content of rice and thereby promoting plant growth. The study also revealed the As accumulation property of NBRI012 strain which could play an important role in As removal from contaminated soil. Furthermore, NBRI012 inoculation significantly restored the hampered root epidermal and cortical cell growth of rice plant and root hair elimination. Altogether our study highlights the multifarious role of B. diminuta in mediating stress tolerance and modulating translocation of As in edible part of rice plant. © 2015 Elsevier Inc.
Comprehensive analysis of uncertainty quantification for the 58Ni(n, p)58Co reaction cross section
(Institute of Physics, 2024) Mahesh Choudhary; Aman Sharma; Namrata Singh; Mahima Upadhyay; Punit Dubey; A. Gandhi; Akash Hingu; G. Mishra; Sukanya De; L.S. Danu; Ajay Kumar; R.G. Thomas; Saurav Sood; Sajin Prasad; S. Mukherjee; I.N. Ruskov; Yu. N. Kopatch; A. Kumar
In this study, we measured the 58Ni(n, p)58Co reaction cross section with neutron energies of 1.06, 1.86, and 2.85 MeV. The cross section was measured using neutron activation techniques and γ-ray spectroscopy, and it was compared with cross section data available in the EXFOR. Furthermore, we calculated the covariance matrix of the measured cross section for the aforementioned nuclear reaction. The uncertainties of the theoretical calculation for 58Ni(n, p)58Co reaction cross section were calculated via Monte Carlo method. In this study, we used uncertainties in the optical model and level density parameters to calculate uncertainties in the theoretical cross sections. The theoretical calculations were performed by using TALYS-1.96. In this study, we aim to analyze the effect of uncertainties of the nuclear model input as well as different experimental variables used to obtain the values of reaction cross section. © 2024 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Design and development of benzyl piperazine linked 5-phenyl-1,2,4-triazole-3-thione conjugates as potential agents to combat Alzheimer's disease
(Academic Press Inc., 2023) Pidugu Venkata Ravi Kiran; Digambar Kumar Waiker; Akash Verma; Poorvi Saraf; Bhagwati Bhardwaj; Hansal Kumar; Abhinav Singh; Pradeep Kumar; Namrata Singh; Saripella Srikrishna; Surendra Kumar Trigun; Sushant Kumar Shrivastava
Our present work demonstrates the molecular hybridization-assisted design, synthesis, and biological evaluation of 22 benzylpiperazine-linked 1,2,4-triazole compounds (PD1-22) as AD modifying agents. All the compounds were tested for their in vitro hChEs, hBACE-1, and Aβ-aggregation inhibition properties. Among them, compound PD-08 and PD-22 demonstrated good hChE and hBACE-1 inhibition as compared to standards donepezil and rivastigmine. Both compounds displaced PI from PAS at 50 µM concentration which was comparable to donepezil and also demonstrated anti-Aβ aggregation properties in self- and AChE-induced thioflavin T assay. Both compounds have shown excellent BBB permeation via PAMPA-BBB assay and were found to be non-neurotoxic at 80 µM concentration against differentiated SH-SY5Y cell lines. Compound PD-22 demonstrated an increase in rescued eye phenotype in Aβ-phenotypic drosophila AD model and amelioration of behavioral deficits in the Aβ-induced rat model of AD. The in-silico docking studies of compound PD-22 revealed a good binding profile towards CAS and PAS residues of AChE and the catalytic dyad of the BACE-1. The 100 ns molecular dynamics simulation studies of compound PD-22 complexed with AChE and BACE-1 enzymes suggested stable ligand-protein complex throughout the simulation run. Based on our findings compound PD-22 could further be utilized as a lead to design a promising candidate for AD therapy © 2023 Elsevier Inc.
Design, Synthesis, and Biological Evaluation of Piperazine and N-Benzylpiperidine Hybrids of 5-Phenyl-1,3,4-oxadiazol-2-thiol as Potential Multitargeted Ligands for Alzheimer’s Disease Therapy
(American Chemical Society, 2023) Digambar Kumar Waiker; Akash Verma; None Akhilesh; T.A. Gajendra; Namrata Singh; Anima Roy; Hagera Dilnashin; Vinod Tiwari; Surendra Kumar Trigun; Surya P. Singh; Sairam Krishnamurthy; Prem Lama; Vincent Jo Davisson; Sushant Kumar Shrivastava
Our present work demonstrates the successful design and synthesis of a new class of compounds based upon a multitargeted directed ligand design approach to discover new agents for use in Alzheimer’s disease (AD). All the compounds were tested for their in vitro inhibitory potential against human acetylcholinesterase (hAChE), human butylcholinesterase (hBChE), β-secretase-1 (hBACE-1), and amyloid β (Aβ) aggregation. Compounds 5d and 5f have shown hAChE and hBACE-1 inhibition comparable to donepezil, while hBChE inhibition was comparable to rivastigmine. Compounds 5d and 5f also demonstrated a significant reduction in the formation of Aβ aggregates through the thioflavin T assay and confocal, atomic force, and scanning electron microscopy studies and significantly displaced the total propidium iodide, that is, 54 and 51% at 50 μM concentrations, respectively. Compounds 5d and 5f were devoid of neurotoxic liabilities against RA/BDNF (RA = retinoic acid; BDNF = brain-derived neurotrophic factor)-differentiated SH-SY5Y neuroblastoma cell lines at 10-80 μM concentrations. In both the scopolamine- and Aβ-induced mouse models for AD, compounds 5d and 5f demonstrated significant restoration of learning and memory behaviors. A series of ex vivo studies of hippocampal and cortex brain homogenates showed that 5d and 5f elicit decreases in AChE, malondialdehyde, and nitric oxide levels, an increase in glutathione level, and reduced levels of pro-inflammatory cytokines, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) mRNA. The histopathological examination of mice revealed normal neuronal appearance in the hippocampal and cortex regions of the brain. Western blot analysis of the same tissue indicated a reduction in Aβ, amyloid precursor protein (APP)/Aβ, BACE-1, and tau protein levels, which were non-significant compared to the sham group. The immunohistochemical analysis also showed significantly lower expression of BACE-1 and Aβ levels, which was comparable to donepezil-treated group. Compounds 5d and 5f represent new lead candidates for developing AD therapeutics. © 2023 American Chemical Society.
Design, Synthesis, and Biological Investigation of Quinazoline Derivatives as Multitargeting Therapeutics in Alzheimer’s Disease Therapy
(American Chemical Society, 2024) Akash Verma; Digambar Kumar Waiker; Neha Singh; Anima Roy; Namrata Singh; Poorvi Saraf; Bhagwati Bhardwaj; Sairam Krishnamurthy; Surendra Kumar Trigun; Sushant Kumar Shrivastava
An efficient and promising method of treating complex neurodegenerative diseases like Alzheimer’s disease (AD) is the multitarget-directed approach. Here in this work, a series of quinazoline derivatives (AV-1 to AV-21) were rationally designed, synthesized, and biologically evaluated as multitargeted directed ligands against human cholinesterase (hChE) and human β-secretase (hBACE-1) that exhibit moderate to good inhibitory effects. Compounds AV-1, AV-2, and AV-3 from the series demonstrated balanced and significant inhibition against these targets. These compounds also displayed excellent blood−brain barrier permeability via the PAMPA-BBB assay. Compound AV-2 significantly displaced propidium iodide (PI) from the acetylcholinesterase-peripheral anionic site (AChE-PAS) and was found to be non-neurotoxic at the maximum tested concentration (80 μM) against differentiated SH-SY5Y cell lines. Compound AV-2 also prevented AChE- and self-induced Aβ aggregation in the thioflavin T assay. Additionally, compound AV-2 significantly ameliorated scopolamine and Aβ-induced cognitive impairments in the in vivo behavioral Y-maze and Morris water maze studies, respectively. The ex vivo and biochemical analysis further revealed good hippocampal AChE inhibition and the antioxidant potential of the compound AV-2. Western blot and immunohistochemical (IHC) analysis of hippocampal brain revealed reduced Aβ, BACE-1, APP/Aβ, and Tau molecular protein expressions levels. The pharmacokinetic analysis of compound AV-2 demonstrated significant oral absorption with good bioavailability. The in silico molecular modeling studies of lead compound AV-2 moreover demonstrated a reasonable binding profile with AChE and BACE-1 enzymes and stable ligand−protein complexes throughout the 100 ns run. Compound AV-2 can be regarded as the lead candidate and could be explored more for AD therapy. © 2024 American Chemical Society.
Erratum: Measurement of ( n, α) and ( n, 2n) reaction cross sections at a neutron energy of 14.92 ± 0.02 MeV for potassium and copper with uncertainty propagation (Chinese Physics C (2022) 46 (014002) DOI: 10.1088/1674-1137/ac2ed4)
(Institute of Physics, 2022) A. Gandhi; Aman Sharma; Rebecca Pachuau; Namrata Singh; L.S. Danu; S.V. Suryanarayana; B.K. Nayak; A. Kumar
Experimentally measured neutron activation cross sections are presented for the 65Cu(n, α)62m Cu, 41K(n, α)38 Cl, and 65Cu(n,2n)64 Cu reactions with detailed uncertainty propagation. The neutron cross sections were measured at an incident energy of 14.92 0.02 MeV, and the neutrons were based on the t(d, n)α fusion reaction. The 27Al(n, α)24 Na reaction was used as a reference reaction for the normalization of the neutron flux. The pre-calibrated lead-shielded HPGe detector was used to detect the residues' γ-ray spectra. The data from the measured cross sections are compared to the previously measured cross sections from the EXFOR database, theoretically calculated cross sections using the TALYS and EMPIRE codes, and evaluated nuclear data. © 2022 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Estimation of global level density parameters using an unscented transform Kalman filter technique
(American Physical Society, 2024) Mahesh Choudhary; Aman Sharma; Namrata Singh; Punit Dubey; Mahima Upadhyay; Sriya Paul; Shweta Singh; Utkarsha Mishra; A. Kumar; S. Dasgupta; J. Datta
This study focuses on estimating the level density parameters for niobium (Nb) using the unscented transform Kalman filter technique. Niobium is widely utilized in accelerator components, particularly in superconducting radiofrequency cavities. To better understand the design of accelerator components and experimental setups, accurate information on both theoretical predictions and experimental results, including the uncertainties of nuclear reactions involving niobium, is essential. In this study, we have used the unscented transform Kalman filter technique to estimate level density parameters and their correlation matrix for Nb93(α,2n)Tc95 and Nb93(α,n)Tc96 reactions through the talys nuclear code. We have used the measured experimental nuclear reaction cross sections from this study to estimate the level density parameters for the above nuclear reactions. A comprehensive analysis of uncertainty propagation has been also conducted, encompassing both theoretical predictions and experimentally measured nuclear reaction cross sections. We have calculated uncertainties in both the theoretical calculations using the Monte Carlo method and experimentally measured reaction cross sections through covariance analysis for these nuclear reactions. We have also calculated the correlation matrix of the experimentally measured cross sections for the Nb93(α,n)Tc95 and Nb93(α,n)Tc96 nuclear reactions. © 2024 American Physical Society.
Excitation functions for natAg(α,x) reactions with detailed covariance analysis
(Elsevier B.V., 2024) Mahesh Choudhary; Namrata Singh; Mahima Upadhyay; Punit Dubey; Shweta Singh; Sriya Paul; Utkarsha Mishra; S. Dasgupta; J. Datta; A. Kumar
Natural silver targets were irradiated using an alpha particle beam to measure the activation cross sections of radioisotopes within the energy range of 23–40 MeV. The newly obtained cross section data, compared with previous experimental results, underline the importance of this work in the context of nuclear reactions and medical applications. Alpha particle induced reaction with natAg involved the production of radioisotopes such as 111In, 105Ag, 106mAg. In this study, we focused on calculating correlation matrices for the natAg(α,x) nuclear reactions. These matrices were generated by considering various interconnected variables, such as decay constants, particle number densities, γ-ray intensities and detector efficiencies for both monitor and sample nuclear reaction products. © 2024 Elsevier B.V.
Excitation functions of alpha-particle induced nuclear reactions on nat Sn
(Walter de Gruyter GmbH, 2024) Mahesh Choudhary; Namrata Singh; Aman Sharma; Aman Gandhi; Mahima Upadhyay; Rebecca Pachuau; Sandipan Dasgupta; Jagannath Datta; Ajay Kumar
Excitation functions of alpha-particle induced nuclear reactions on nat Sn have been presented in the 11-40 MeV energy range. In the present study, the stacked-foil activation technique followed by offline gamma-ray spectrometry was used to measure the production of 119Te, 121Te, 122Sb and 126Sb from alpha-particle induced reactions on nat Sn. The TALYS nuclear code was used to calculate the theoretical predictions of the excitation functions of nat Sn(α,x) nuclear reactions. The measured data of the above-mentioned nuclear reactions were compared with the theoretical predictions and the experimental results available from EXFOR. In this study, covariance analysis was performed to calculate the uncertainty propagation in the measured cross sections. © 2023 Walter de Gruyter GmbH, Berlin/Boston.
Exploitation of surrogate reaction method for deriving proton induced fission cross sections of short lived actinides
(Institute of Physics Publishing, 2020) Aman Sharma; A. Gandhi; Namrata Singh; S.V. Suryanarayana; B.K. Nayak; A. Kumar
In this article we have explored the possibility of measuring the proton induced fission cross sections using surrogate reaction method. To establish the validity of the surrogate method, we have derived the cross sections for 240Pu(p, f), 234Th(p, f), 236U(p, f) and 233Th(p, f) reactions using the derived cross section data of 240Am(n, f), 234Pa(n, f), 236Np(n, f) and 233Pa(n, f) reactions, which were measured by the surrogate ratio method. To extract the data, we have used the independence hypothesis of compound nucleus formation and derived a relation between proton and neutron induced fission cross sections of the consecutive isobars. The validity of the Weisskopf-Ewing approximation has been studied in detail. This study successfully confirms that the surrogate ratio method can be used to derive (p, f) cross sections of the short lived actinides. It is also concluded that a common surrogate reaction can be used for the determination of (n, f) and (p, f) cross sections for the consecutive isobars. © 2020 IOP Publishing Ltd.
Induction of cryptic and bioactive metabolites through natural dietary components in an endophytic fungus colletotrichum gloeosporioides (Penz.) sacc
(Frontiers Media S.A., 2017) Vijay K. Sharma; Jitendra Kumar; Dheeraj K. Singh; Ashish Mishra; Satish K. Verma; Surendra K. Gond; Anuj Kumar; Namrata Singh; Ravindra N. Kharwar
Grape skin and turmeric extracts having the major components resveratrol and curcumin, respectively, were used for the induction of cryptic and bioactive metabolites in an endophytic fungus Colletotrichum gloeosporioides isolated from Syzygium cumini. The increase in total amount of crude compounds in grape skin and turmeric extract treated cultures was 272.48 and 174.32%, respectively, compared to the untreated control. Among six human pathogenic bacteria tested, the maximum inhibitory activity was found against Aeromonas hydrophila IMS/GN11 while no inhibitory activity was observed against Enterococcus faecalis IMS/GN7. The crude compounds derived from turmeric extract treated cultures showed the highest DPPH free radicals scavenging activity (86.46% inhibition) followed by compounds from grape skin treated cultures (11.80% inhibition) and the control cultures (1.92% inhibition). Both the treatments significantly (p ≤ 0.05) increased the antibacterial and antioxidant activities of crude metabolites compared to the control. HPLC profiling of crude compounds derived from grape skin and turmeric extract treated cultures revealed the presence of additional 20 and 14 cryptic compounds, respectively, compared to the control. These findings advocate the future use of such dietary components in induced production of cryptic and bioactive metabolites. © 2017 Sharma, Kumar, Singh, Mishra, Verma, Gond, Kumar, Singh and Kharwar.
Influence of inoculation of arsenic-resistant Staphylococcus arlettae on growth and arsenic uptake in Brassica juncea (L.) Czern. Var. R-46
(Elsevier, 2013) Shubhi Srivastava; Praveen C. Verma; Vasvi Chaudhry; Namrata Singh; P.C. Abhilash; Kalpana V. Kumar; Neeta Sharma; Nandita Singh
An arsenic hypertolerant bacterium was isolated from arsenic contaminated site of West Bengal, India. The bacteria was identified as Staphylococcus arlettae strain NBRIEAG-6, based on 16S rDNA analysis. S. arlettae was able to remove arsenic from liquid media and possesses arsC gene, gene responsible for arsenate reductase activity. The biochemical profiling of the isolated strain showed that it had the capacity of producing indole acetic acid (IAA), siderophores and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase. Furthermore, an experiment was conducted to test the effect of S. arlettae inoculation on concurrent plant growth promotion and arsenic uptake in Indian mustard plant [Brassica juncea (L.) Czern. Var. R-46] when grown in arsenic spiked (5, 10 and 15mgkg-1) soil. The microbial inoculation significantly (p<0.05) increased biomass, protein, chlorophyll and carotenoids contents in test plant. Moreover, as compared to the non-inoculated control, the As concentration in shoot and root of inoculated plants were increased from 3.73 to 34.16% and 87.35 to 99.93%, respectively. The experimental results show that the plant growth promoting bacteria NBRIEAG-6 has the ability to help B. juncea to accumulate As maximally in plant root, and therefore it can be accounted as a new bacteria for As phytostabilization. © 2012 Elsevier B.V.
Investigation of 58Ni (n, p)58Co reaction cross-section with covariance analysis
(Institute of Physics, 2024) Akash Hingu; S. Mukherjee; Siddharth Parashari; Arora Sangeeta; A. Gandhi; Mahima Upadhyay; Mahesh Choudhary; Sumit Bamal; Namrata Singh; G. Mishra; Sukanya De; Saurav Sood; Sajin Prasad; G. Saxena; Ajay Kumar; R.G. Thomas; B.K. Agrawal; K. Katovsky; A. Kumar
The excitation function of the reaction was measured using the well-established neutron activation technique and γ-ray spectroscopy. Neutrons in the energy range of 1.7 to 2.7 were generated using the reaction. The neutron flux was measured using the standard monitor reaction. The results of the neutron spectrum averaged cross-section of reactions were compared with existing cross-section data available in the EXFOR data library as well as with various evaluated data libraries such as ENDF/B-VIII.0, JEFF-3.3, JENDL-4.0, and CENDL-3.2. Theoretical calculations were performed using the nuclear reaction code TALYS. Various nuclear level density (NLD) models were tested, and their results were compared with the present findings. Realistic NLDs were also obtained through the spectral distribution method (SDM). The cross-section results, along with the absolute errors, were obtained by investigating the uncertainty propagation and using the covariance technique. Corrections for γ-ray true coincidence summing, low-energy background neutrons, and γ-ray self attenuation were performed. The experimental cross-section obtained in the present study is consistent with previously published experimental data, evaluated libraries, and theoretical calculations carried out using the TALYS code. © 2024 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Measurement of (n,α) and (n,2n) reaction cross sections at a neutron energy of 14.92 ± 0.02 MeV for potassium and copper with uncertainty propagation
(Institute of Physics, 2022) A. Gandhi; Aman Sharma; Rebecca Pachuau; Namrata Singh; L.S. Danu; S.V. Suryanarayana; B.K. Nayak; A. Kumar
Experimentally measured neutron activation cross sections are presented for the 65Cu(n,α)62mCu, 41K(n,α)38Cl, and 65Cu(n,2n) 64Cu reactions with detailed uncertainty propagation. The neutron cross sections were measured at an incident energy of 14.92 ± 0.02 MeV, and the neutrons were based on the t(d,n)α fusion reaction. The 27Al(n,α)naNa reaction was used as a reference reaction for the normalization of the neutron flux. The pre-calibrated lead-shielded HPGe detector was used to detect the residues' γ-ray spectra. The data from the measured cross sections are compared to the previously measured cross sections from the EXFOR database, theoretically calculated cross sections using the TALYS and EMPIRE codes, and evaluated nuclear data. © 2022 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Measurement of alpha-induced reaction cross-sections for natZn with detailed covariance analysis
(Elsevier B.V., 2023) Mahesh Choudhary; Aman Sharma; Namrata Singh; A. Gandhi; S. Dasgupta; J. Datta; K. Katovsky; A. Kumar
The production cross-section of 68Ge, 69Ge, 65Zn and 67Ga radioisotopes from alpha-induced nuclear reaction with natZn have been measured using the stacked foil activation technique followed by the off-line γ-ray spectroscopy in the incident alpha energy range 14-37 MeV. The obtained nuclear reaction cross-sections are compared with previous experimental data available in the EXFOR data library, evaluated nuclear data from TENDL-2019 and theoretical results, calculated using TALYS nuclear reaction code. We have also performed the detailed uncertainty analysis for these nuclear reactions and their respective correlation metrics are presented. Since α-induced reactions are important in nuclear medicine and developing the nuclear reaction codes so needful corrections related to the coincidence summing factor and the geometric factor have been considered during the data analysis in the present study. © 2023 Elsevier B.V.
Measurement of alpha-induced reaction cross-sections on nat Mo with detailed covariance analysis
(Springer Science and Business Media Deutschland GmbH, 2022) Mahesh Choudhary; A. Gandhi; Aman Sharma; Namrata Singh; Punit Dubey; Mahima Upadhyay; S. Dasgupta; J. Datta; A. Kumar
In the present study we have measured the excitation functions for the nuclear reactions natMo(α,x)103Ru, natMo(α,x)97Ru, natMo(α,x)95Ru, natMo(α,x)96gTc, natMo(α,x)95gTc and natMo(α,x)94gTc in the energy range 9–32 MeV. We have used the stacked foil activation technique followed by the offline gamma-ray spectroscopy technique to measure the excitation functions. In this study we have also documented detailed uncertainty analysis for these nuclear reactions and their corresponding covariance matrix are also presented. The excitation functions are compared with the available experimental data from EXFOR data library and the theoretical prediction from TALYS nuclear reaction code. © 2022, The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature.
Measurement of excitation functions for natCu(α, x) reactions with detailed covariance analysis
(Institute of Physics, 2023) Mahesh Choudhary; Aman Sharma; A. Gandhi; Namrata Singh; Punit Dubey; Mahima Upadhyay; Utkarsha Mishra; N.K. Dubey; S. Dasgupta; J. Datta; K. Katovsky; A. Kumar
The excitation functions of 66Ga, 67Ga, 65Zn and 64Cu radioisotopes produced via alpha-induced reaction on nat Cu were measured using a stacked foil activation method. The gamma-ray activity produced by the above mentioned radionuclides was measured using the HPGe detector. The covariance analysis was performed to quantify the measured cross-section uncertainties as well as the correlation between different alpha energy cross-sections. A covariance matrix and cross-sections for the natCu(α, x)66Ga, natCu(α, x)67Ga, natCu(α, x)65Zn and natCu(α, x)64Cu nuclear reactions in the projectile energy range of 15-37 MeV are reported in the present work. The measured reaction cross-sections are compared with the existing experimental data and theoretically simulated results from the TALYS code. © 2022 IOP Publishing Ltd.
Measurement of neutron capture cross section on 71Ga at 2.15 and 3.19 MeV and uncertainty propagation and covariance analysis
(Institute of Physics, 2023) Rebecca Pachuau; A. Gandhi; Namrata Singh; A. Kumar; Mayur Mehta; S.V. Suryanarayana; L.S. Danu; B.K. Nayak; B. Lalremruata
The cross section values of the Ga( ) Ga reaction are measured, which are mb and mb at 2.15 and 3.19 MeV, respectively. The detailed uncertainty propagation and covariance analysis are also given. The Li( ) Be reaction was used to generate the neutrons, and the neutron flux was normalized using the In( ) In monitor reaction. The measured cross section data are compared with the data available in the EXFOR database, the data obtained using nuclear reaction model codes EMPIRE-3.2 and TALYS-1.95, and also the evaluated nuclear data from ENDF/B-VIII.0 and JEFF-3.1/A. The comparison shows that our result at 3.19 MeV is in good agreement with those of EMPIRE-3.2 and JEFF-3.1/A. Since there are no other measurements available at 3.19 MeV, our data could not be compared with literature data at 3.19 MeV, but they are consistent with the cross section values available at and MeV. Our result at 2.15 MeV is slightly higher than the literature value available in EXFOR, evaluated value, and theoretically predicted result. © 2023 Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Sciences and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.