Arbuscular mycorrhizal fungi and associated bacteria isolated from salt-affected soil enhances the tolerance of maize to salinity in coastal reclamation soil

Krishnamoorthy, R.,Kim, K.,Subramanian, P.,Senthilkumar, M.,Anandham, R.,Sa, T. Elsevier 2016 Agriculture, ecosystems & environment Vol.231 No.-

Arbuscular mycorrhizal fungi (AMF) have close association with bacteria in establishing a tripartite interaction with plants. The objective of this study was to assess the tripartite interactions among AMF, associated bacteria and maize on enhancing salt stress tolerance. AMF spores isolated from coastal reclamation land were identified as Rhizophagus intraradices and multiplied using monosporic mass culturing. From surface-decontaminated spores of R. intraradices, isolation of associated bacteria was carried out and the obtained isolate was identified as Massilia sp. RK4. The isolated bacterial strain was found to possess several plant growth promoting characteristics and for further studies, its effect on maize plant growth in coastal reclamation soil was evaluated under three different salt concentrations. Salt stress substantially reduced plant growth, root colonization and spore-producing ability of the R. intraradices. However, treatment with the AMF and a combination of AMF and associated bacteria alleviated the salt-induced reduction of plant growth, root colonization, nutrient accumulation and lowered leaf proline levels compared to control treatment. The co-inoculation of R. intraradices and Massilia sp. RK4 exhibited significant impact on AMF root colonization and nutrient accumulation in plants compared to inoculation with R. intraradices only. Inoculation of R. intraradices and Massilia sp. RK4 improved the salinity tolerance of maize through the dual effect exerted by AMF and its associated bacteria.

Buckling Behaviour of Hollow Flange Channel Beam Sections in Bending

R. Senthilkumar,T. S. Sunil,P. Jayabalan 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.5

The hollow fl ange beams are designed to take the advantages of hot-rolled steel sections in which area is concentrated away from the neutral axis and the ease of installation associated with cold-formed sections. The present study deals with the fl exural behaviour of hollow fl ange channel beams sections by Finite Element modeling using the general purpose fi nite element software ABAQUS. A Parametric study is carried out by varying the fl at width/thickness ratio, depth of the beam, depth of the hollow fl ange and length of the beam. The eff ects of distortional buckling on hollow fl ange channel beam are studied and fi nite element model results are compared with AS/NZS 4600:2005 code for cold-formed steel structures. It is found that code based design is economic for hollow fl ange beams which fail in lateral distortional buckling alone.

Performance investigation of heat pipe using aqueous solution of n-Pentanol with different inclinations

R. Senthilkumar,S. Vaidyanathan,B. Sivaraman 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.4

The orientation of the heat pipe plays the significant role in its performance. In specific orientations, the performance of the heat pipe is directly related to the wick structure. In conventional heat pipe, the working fluid is used a negative surface-tension gradient with temperature. It is an unfavorable one and it decreases the heat transport between the evaporator section and the condenser section. An Aqueous solution of n-Pentanol having a positive surface tension gradient with temperature is suggested as a working medium for heat pipe to improve the performance of capillary limit and operating stability. The objective of this paper is to perform a comparative study of heat pipe performance using the aqueous solution of n-Pentanol with water at various inclinations. The results are presented to demonstrate the merits and suitability of the aqueous solution of n-Pentanol as a working fluid for heat pipe.

GSTM1 and GSTT1 Allele Frequencies among Various Indian and non-Indian Ethnic Groups

Senthilkumar, K.P.,Thirumurugan, R. Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.12

Background: Glutathione-S-transferase (GST) is an important phase II xenobiotic compound metabolizing enzyme family, involved in tolerance to a particular drug or susceptibility to a diseasec. This study focused the GSTM1 and T1 null allele frequency in the Gujarat population with a comparison across other Inter- and Intra-Indian ethnic groups to predict variation in the possible susceptible status. Methods: DNA was isolated by a salting out method and GSTM1 and T1 homozygous null genotypes were detected by multiplex polymerase chain reaction in 504 unrelated individuals. The genotype distribution of null alleles was compared with Indian and non Indian ethnics reported earlier in the literature using Fisher's test. Results: The frequencies of the homozygous null genotypes of GSTM1 and GSTT1 were 20% (95%CI 16.7-23.9) and 35.5% (95%CI 31.4-39.9) respectively. GSTM1 null frequency did not deviate from most other Indian ethnic groups but differed from the majority of those of non Indian ethnicity studied. The frequency of homozygous null type of GSTT1 was significantly higher and deviated from all Indian groups and a few of non Indian ethnicity. Conclusions: Gujarat ethnicity, possibly the most susceptible for GSTT1 dependent drug disposition and diseases regarding effects of pollution. Further, the results have implications for GSTT1 dependent drugs used for treatment, a serious problem which needs to be solved by physicians and clinical researchers.

Hand arm vibration measurement using micro-accelerometer in different brick structures

Gomathi, K.,Senthilkumar, A.,Shankar, S.,Thangavel, S.,Priya, R. Mohana Techno-Press 2014 Smart Structures and Systems, An International Jou Vol.13 No.6

Hand-Arm Vibration Syndrome (HAVS) is a group of diseases caused by exposure of the hands to vibration while operating the hand held power tools such as road breaker, drilling machine, demolition hammer in construction works. In this paper, area-changed capacitive micro-accelerometer is designed to measure the vibration exposure on worker's hand when operating a drilling machine on various blocks such as clay block, paver block and solid cement block. The design process includes mathematical modelling of micro-accelerometer and simulations are done using INTELLISUITE 8.6. Experimental results are taken for various blocks surfaces using conventional and micro-accelerometer. Comparisons show that usage of area-changed micro-accelerometer for Hand-arm vibration monitoring provides better sensitivity, which in turn reduces the risk of HAVS in workers.

Biodiversity of Microalgae and Their Elemental Components from Veeranam Lake, Tamilnadu, India

Sivakumar K.,R. Senthilkumar 한국하천호수학회 2008 생태와 환경 Vol.41 No.2

Role of TiC and h-BN particles on morphological characterization and surface effects of Al 4032 hybrid composites using EDM process

T. S. Senthilkumar,R. Muralikannan 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.9

Aluminum based hybrid metal matrix composites (HMMCs) are utilized in myriad of applications owing to their attractive properties such as low weight to high strength ratio, enriched mechanical and thermal properties over other conventional materials. In this work, the consequence of TiC and h-BN particles on morphological characterization and surface effects of aluminium based HMMCs during electrical discharge machining (EDM) process is discussed. The HMMCs are fabricated by varying the wt. % of TiC and then EDM is done by examining the input parameters such as peak current (A), pulse on time (µs) and gap voltage (v) under L 27 orthogonal array method. The performance and surface effects of the machined surface are evaluated after completing the EDM process. The MRR appears to surge with the rise in the peak current and decays with increasing the wt. % of TiC particles. Although by amplifying the wt. % of TiC particles, the size of the craters and the voids is augmented on the machined surface. Furthermore, as the peak current upsurges, the microhardness of the machined samples are augmented.

Biodiversity of Microalgae and Their Elemental Components from Veeranam Lake, Tamilnadu, India

Sivakumar, K.,Senthilkumar, R. The Korean Society of Limnology 2008 생태와 환경 Vol.37 No.1

An attempt was made in the Veeranam freshwater lake with the objectives to collect, identify, describe and document the algae occurring from March 2007 to August 2007. Qualitative and quantitative characterization of phytoplankton and analysis of physico-chemical parameters of water samples were carried out at monthly intervals during the study period in the western and eastern sides of the lake. It was found that the phytoplankton community embraced 68 genera belonging to four classes viz., Bacillariophyceae (40), Chlorophyceae (22), Cynophyceae (4) and Euglenophyceae (2). There were significant influences of various physico-chemical parameters on the phytoplankton population density. Commonly occurred genera, Oscillatoria (Cyanophyceae), Navicula (Bacillariophyceae) and Scenedesmus (Chlorophyceae), were subjected to energy dispersive spectroscopic analysis (EDS). They were found to accumulate different elements such as Zn, P, S, Ca, Mg, Fe, N, Si, Cl and Mn. Among these the member Cyanophyceae contained Zn, P, Mg, Ca, Mn, S and N. Bacillariophyceae Si, Zn, Mg, Cl, N, Fe, and Ca. Chlorophyceae Ca, Mg, N, Fe, Cl, Zn, Si and Mn. Thus these observations would determine the chemical dialogue between the cell structures and role of the elements. Further, it gives the clue about the phytoplankton growth requirements.

Flexural behaviour of reinforced concrete beams with silica fume and processed quarry fines

Priya, T. Shanmuga,Senthilkumar, R. Techno-Press 2020 Advances in concrete construction Vol.10 No.2

This paper studies the influence of silica fume and Processed Quarry Fines (PQF) on the flexural behaviour of the reinforced concrete beams by experimental as well as numerical studies. The study has been shown that the incorporation of PQF can significantly increase the stiffness and the flexural strength of reinforced HPC beams. Also, the ultimate strength of specimens prepared with the 10% silica fume and 100% PQF are higher compared to conventional reinforced concrete specimen. Numerical analysis is performed to find the ultimate strength of HPC beams to compare with experimental results. Nonlinear behaviour of steel reinforcing bars and plain concrete is simulated using appropriate constitutive models and experimental results. The results indicate that the ultimate strength, deformed shape and crack patterns of reinforced HPC beams obtained through the Finite Element Analysis (FEA) are confirming with the experimental results.

Honeycomb Monolith Coated with Mo(VI)/ZrO₂ as a Versatile Catalyst System for Liquid Phase Transesterification

Thimmaraju, N.,Pratap, S.R.,Senthilkumar, M.,Mohamed Shamshuddin, S.Z. Korean Chemical Society 2012 대한화학회지 Vol.56 No.5

Solid acid Mo(VI)/$ZrO_2$ with 2-10% Mo(VI) was coated on honeycomb monoliths by impregnation method. These catalytic materials were characterized by BET, $NH_3$-TPD/n-butylamine back titration, PXRD and SEM techniques. Phenyl salicylate (Salol) was synthesized via transesterification of methyl salicylate and phenol over these catalytic materials. An excellent yield (91.0%) of salol was obtained under specific reaction conditions. The effect of poisoning of acid sites of the catalytic material by adsorbing different bases and its effect on total surface acidity, powder XRD phases and catalytic activity was studied. A triangular correlation between the surface acidity, powder XRD phases and catalytic activity of Mo(VI)/$ZrO_2$ was observed. The thermally regenerated catalytic material was reused repeatedly with a consistent high yield of salol.