The radiation shielding proficiency and hyperspectral-based spatial distribution of lateritic terrain mapping in Irikkur block, Kannur, Kerala

Arivazhagan S.,Naseer K.A.,Mahmoud K.A.,Libeesh N.K.,Arun Kumar K.V.,Naga Kumar K.ChV.,Sayyed M.I.,Alqahtani Mohammed S.,Shiekh E. El,Khandaker Mayeen Uddin 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

The practice of identifying the potential zones for mineral exploration in a speedy and low-cost method includes the use of satellite imagery analysis as a part of remote sensing techniques. It is challenging to explore the iron mineralization of a region through conventional methods which are a time-consuming process. The current study utilizes the Hyperion satellite imagery for mapping the iron mineralization and associated geological features in the Irikkur region, Kannur, Kerala. Along with the remote sensing results, the field study and laboratory-based analysis were conducted to retrieve the ground truth point and geochemical proportion to verify the iron ore mineralization. The MC simulation showed for shielding properties indicate an increase in the linear attenuation coefficient with raising the Fe2O3þSiO2 concentrations in the investigated rocks where it is varied at 0.662 MeV in the range 0.190 cm1 - 0.222 cm1 with rising the Fe2O3þSiO2 content from 57.86 wt% to 71.15 wt%. The analysis also revealed that when the g-ray energy increased from 0.221 MeV to 2.506 MeV, sample 1 had the largest linear attenuation coefficient, ranging from 9.33 cm1 to 0.12 cm1 . Charnockite rocks were found to have exceptional shielding qualities, making them an excellent natural choice for radiation shielding applications.

Influence of Low Nickel (0.09 wt%) Content on Microstructure and Toughness of P91 Steel Welds

B. Arivazhagan,M. Vasudevan,M. Kamaraj 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.3

Modified 9Cr-1Mo (P91) steel is widely used as a high temperature structural material in the fabrication of power plant components. Alloying elements significantly influences the microstructure and mechanical properties of P91 steel weldments. The alloying elements manganese and nickel significantly influence the lower critical phase transformation temperature (AC1) as well as tempering response of welds. In the existing published information there was wide spread use of high Mn+Ni filler wire. In the present study, weldment preparation was completed using GTA filler wire having low Nickel content (Mn+Ni of 0.58 wt% including nickel content of 0.09 wt%). Microstructure and mechanical properties characterization was done. There is a requirement on minimum toughness of 47 Joules for P91 steel tempered welds at room temperature. Microstructural observation revealed that the GTA welds have low δ-ferrite content (< 0.5%) in the martensite matrix. In the as-weld condition, the toughness was 28 Joules whereas after PWHT at 760 °C-2 h it was 115 Joules. In the present study, toughness of low nickel weld was higher due to low δ-ferrite content (<0.5%), multipass grain refinement and weld metal deposition of single pass per layer of weldment.

The radiation shielding competence and imaging spectroscopic based studies of Iron ore region of Kozhikode district, Kerala

S. Arivazhagan,K.A. Naseer,K.A. Mahmoud,S.A. Bassam,P.N. Naseef Mohammed,N.K. Libeesh,A.S. Sachana,M.I. Sayyed,Mohammed S. Alqahtani,E. El Shiekh,Mayeen Uddin Khandaker Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.7

Hyperspectral data and its ability to explore the minerals and their associated rocks have a remarkable application in mineral exploration and lithological characterization. The present study aims to explore the radiation shielding aspects of the iron ore in Kerala with the aid of the Hyperion hyperspectral dataset. The reflectance-spectra obtained from the laboratory conditions as well as from the image show various absorptions. The results from the spectra are validated with geochemical data and GPS points. The Monte Carlo simulation employed to evaluate the radiation shielding ability. Raising the oxygen ions caused a noteworthy decrease in the µ values of the studied rocks which is accompanied by an increase in Δ_0.5 and Δ_eq values. The Δ_0.5 and Δ_eq values increased by factors of approximately 77 % with raising the oxygen ions between 44.32 and 47.57 wt.%. The µ values varies with the oxygen concentrations, where the µ values decreased from 2.531 to 0.925 cm^-1 (at 0.059 MeV), from 0.381to 0.215 cm^-1 (at 0.662 MeV), and from 0.279 to 0.158 cm^-1 (at 1.25 MeV) with raising the oxygen ions from 44.32 to 47.43 wt.%.

Antioxidant property of leaves and calluses extracts of in-vitro grown 5 different Ocimum species

송혁,Prem Kumar,Girija Arivazhagan,Sang-Il Lee,Hyung Moon Yoon,김익희,권혁중,김종문,Faruck Lukmanul Hakkim 한국식물생명공학회 2012 식물생명공학회지 Vol.39 No.3

In this study, the antioxidant property of leaf and callus extracts of five selected in vitro grown Ocimum species (Ocimum sanctum, Ocimum kilimandscharicum, Ocimum gratissimum, Ocimum basilicum, and Ocimum americanum) and their respective callus extracts was investigated. The callus cultures were successfully initiated on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) (1 mg・L) combined with different concentrations (0.1-0.4 mg・L) of kinetin as plant growth regulators. Total phenolic contents were estimated using the Folin-Ciocalteu reagent. 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power, Fe2+ chelating activity, and β-carotenelinoleic acid bleaching assays were used to determine the biological effects of the extracts. Interestingly, all the callus extracts exhibited significant (p<0.05) increase in phenolic contents and antioxidant activity. Furthermore, a liner correlation was obtained between the total phenolic contents and free radical scavenging activity (R2 = 0.783). The extracts of leaves and calluses of Ocimum species exhibited activity in all the in vitro antioxidant assays, but its extent was less potent that the positive controls butylated hydroxyl anisole (BHA) and ascorbic acid. A higher accumulation of phenolics in the callus extracts suggests that isolation of high-concentration materials with antioxidant activivity is possible from in vitro callus cultures rather than field-grown plant organs. Furthermore, these extracts may be used as an effective preservative in the food industry.

Curcumin-Conjugated Gold Clusters for Bioimaging and Anticancer Applications

Govindaraju, Saravanan,Rengaraj, Arunkumar,Arivazhagan, Roshini,Huh, Yun-Suk,Yun, Kyusik American Chemical Society 2018 Bioconjugate chemistry Vol.29 No.2

<P>Curcumin-conjugated gold clusters (CUR-AuNCs) were synthesized using a “green” procedure and utilized as an anticancer and a bioimaging agent. Curcumin is a well-known anticancer agent, which forms a cluster when reacting with a gold precursor under mild alkali condition. A fluorescence spectroscopy analysis showed that the CUR-AuNCs emitted red fluorescence (650 nm) upon visible light (550) irradiation. Fourier transform infrared spectroscopy analysis confirmed the stretching and bending nature between the gold atoms and curcumin. Meanwhile, transmission electron microscopy analysis showed a cluster of approximately 1–3 nm with a uniform size. Time-resolved fluorescence analysis demonstrated that the red fluorescence was highly stable. Moreover, laser confocal imaging and atomic force microscopy analysis illustrated that a cluster was well distributed in the cell. This cluster exhibited less toxicity in the mortal cell line (COS-7) and high toxicity in the cervical cancer cell line (HeLa). The results demonstrated the conjugation of curcumin into the fluorescent gold cluster as a potential material for anticancer therapy and bioimaging applications.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/bcches/2018/bcches.2018.29.issue-2/acs.bioconjchem.7b00683/production/images/medium/bc-2017-00683j_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/bc7b00683'>ACS Electronic Supporting Info</A></P>

Antioxidant property of leaves and calluses extracts of in-vitro grown 5 different Ocimum species

Song, Hyuk,Kumar, Prem,Arivazhagan, Girija,Lee, Sang-Il,Yoon, Hyung-Moon,Kim, Ick-Hee,Kwon, Hyuk-Jung,Kim, Jong-Moon,Hakkim, Faruck Lukmanul The Korean Society of Plant Biotechnology 2012 식물생명공학회지 Vol.39 No.3

In this study, the antioxidant property of leaf and callus extracts of five selected in vitro grown Ocimum species (Ocimum sanctum, Ocimum kilimandscharicum, Ocimum gratissimum, Ocimum basilicum, and Ocimum americanum) and their respective callus extracts was investigated. The callus cultures were successfully initiated on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) (1mg L) combined with different concentrations (0.1-0.4 mg L) of kinetin as plant growth regulators. Total phenolic contents were estimated using the Folin-Ciocalteu reagent. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power, $Fe^{2+}$ chelating activity, and ${\beta}$-carotenelinoleic acid bleaching assays were used to determine the biological effects of the extracts. Interestingly, all the callus extracts exhibited significant (p<0.05) increase in phenolic contents and antioxidant activity. Furthermore, a liner correlation was obtained between the total phenolic contents and free radical scavenging activity ($R^2$ = 0.783). The extracts of leaves and calluses of Ocimum species exhibited activity in all the in vitro antioxidant assays, but its extent was less potent that the positive controls butylated hydroxyl anisole (BHA) and ascorbic acid. A higher accumulation of phenolics in the callus extracts suggests that isolation of high-concentration materials with antioxidant activivity is possible from in vitro callus cultures rather than field-grown plant organs. Furthermore, these extracts may be used as an effective preservative in the food industry.

pH-sensitive tangeretin-ZnO quantum dots exert apoptotic and anti-metastatic effects in metastatic lung cancer cell line

Roshini, A.,Jagadeesan, Srikanth,Arivazhagan, Lakshmi,Cho, Young-Jae,Lim, Jong-Hwan,Doh, Yang-Hoi,Kim, Sang-Jae,Na, Jinhee,Choi, Kyung Hyun Elsevier 2018 Materials science & engineering. C, Materials for Vol.92 No.-

<P><B>Abstract</B></P> <P>Most cancer patients die as a consequence of distant metastases, which are frequently unresponsive to cancer therapy. This study focuses on the anti-tumorigenic and anti-metastatic properties of tangeretin-zinc oxide quantum dots (Tan-ZnO QDs) against the NCI-H358 cell line. Tan-ZnO QDs are pH-sensitive and capitalize on the acidic pH maintained in the tumor microenvironment; therefore, targeted drug delivery is directed specifically to cancer cells, leaving the normal cells less affected. Tan was loaded into synthesized ZnO QDs, and drug loading was analyzed using Fourier transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV–Vis) spectrometry. Crystalline phase and particle size were measured using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Drug release was evaluated in buffered solutions with differing pH for up to 15 h. The results confirmed stable drug release (80%) in an acidic pH. Tan-ZnO QDs induced significant cytotoxicity in NCI-H358 metastatic cells, while not markedly affecting HK-2 human normal cells. Morphology of treated H358 cells analyzed via atomic force microscopy (AFM) showed an increased surface roughness and pores. Further, the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells increased after treatment with Tan-ZnO QDs. DNA fragmentation was also induced after treatment with increasing concentrations of Tan-ZnO QDs in H358 cells. We also confirmed regulation of apoptosis via expression levels of Bax and Bcl-2 proteins; G2/M phase cell cycle arrest was observed. Additionally, cell proliferation and migration drastically decreased, and cell invasion and migration, hallmarks of metastasis, were significantly inhibited in H358 cells. Matrix metalloproteinase (MMP)2 and MMP9, markers of metastasis, as well as vascular endothelial growth factor (VEGF), a marker of angiogenesis, were significantly downregulated upon treatment with Tan-ZnO QDs. In conclusion, our novel formulation destabilized H358 cells by using its acidic tumor microenvironment, thereby regulating cell apoptosis, proliferation, and metastatic properties.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Tan-ZnO QDs are pH sensitive, targeting metastatic lung cancer cells. </LI> <LI> Tan-ZnO QDs significantly inhibit invasion and migration of H358 cells. </LI> <LI> H358 cells treated with Tan-ZnO QDs are destabilized. </LI> <LI> Tan-ZnO QDs regulate apoptosis, proliferation, and metastasis in H358 cells. </LI> </UL> </P>

Effects of Aqueous Extracts of Garlic (Allium sativum) and Neem (Azadirachta indica) Leaf on Hepatic and Blood Oxidant-Antioxidant Status During Experimental Gastric Carcinogenesis

S. Nagini,B. Velmurugan,V. Bhuvaneswari,S. Arivazhagan 한국식품영양과학회 2004 Journal of medicinal food Vol.7 No.3

Characterization of metallurgical and mechanical properties on the multi-pass welding of Inconel 625 and AISI 316L

K. Gokul Kumar,K. Devendranath Ramkumar,N. Arivazhagan 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.3

This article investigated the weldability, metallurgical and mechanical properties of Inconel 625 and AISI 316L stainless steel weldmentsobtained by continuous current (CC) and pulsed current (PC) gas tungsten arc welding (GTAW) processes employing ERNiCr-3and ER2209 fillers. Microstructure studies showed the migrated grain boundaries at the weld zone of ERNiCr-3 weldments and multidirectionalgrain growth for ER2209 weldments. It was inferred from the tension tests that the fracture occurred at the parent metal ofAISI 316L in all the cases. Charpy V-notch impact tests accentuated that the CCGTA weldments employing ERNiCr-3 filler offeredbetter impact toughness of 77 J at room temperature. Further a detailed study has been carried out to analyze the structure - property relationshipsof these weldments using the combined techniques of scanning electron microscopy (SEM) and energy dispersive spectroscopy(EDS) analysis.