SearcharxivSearch

arXiv subjects

T. Theivasanthi

Publications and source records attributed to T. Theivasanthi.

17 recordsLinked to original sources

Synthesis and characterization of cotton fiber-based nanocellulose

Nanocellulose prepared from the natural material has a promising wide range of opportunities to obtain the superior material properties towards various end-products. In this research, commercially available natural cotton was treated with aqueous sodium hydroxide solution to eliminate the hemicellulose and lignin, then cellulose was collected. The collected cellulose was subjected to acid hydrolysis using sulphuric acid to obtain nanocellulose. The prepared nanocellulose was further characterized with the aid of Fourier transform infrared spectroscopy, X-ray diffraction and Scanning Electron Microscopy to elucidate the chemical structure, crystallinity and the morphology.

physics.app-ph

Effect of milling on dispersion of graphene nanosheet reinforcement in different morphology copper powder matrix

The effective dispersion of Graphene Nanosheet (GNS) as reinforcement was studied with various morphology of Copper (Cu) powder as matrix. High energy milling was used for modifying the morphology of the Cu powders. The Cu powder with Spherical and dentric shape was used in this study. Using high energy milling both the powders were milled for 8 h and 16 h respectively. The morphology of Cu powders was altered as flake shape upon milling. GNS (2 wt. %) was added as reinforcement uniformly with various morphology Cu powder used as matrix. The effect of size and shape of Cu as matrix on Cu/GNS composite properties was comprehensively studied. The Cu/GNS composite was prepared using powder metallurgy technique. Using the different shape and size of the Cu as matrix the interface of GNS has been studied. The hardness properties of Cu/GNS composite are evaluated. The effect of GNS interface in Cu particles has a significant influence on mechanical properties of composites. The hardness of Cu matrix composite has improved up to 20% compared to that of pure Cu. Thus morphology of Cu has the ability to improve the mechanical properties with GNS reinforcement.

physics.app-ph

Review on Titania Nanopowder- Processing and Applications

This review work focuses on the milling process of titania (TiO2) nanopowder. TiO2 is a naturally available material. It is an inorganic semi-conducting oxide of titanium metal. Titanium oxide, titanium dioxide, and titanium (IV) oxide are the other names. TiO2 nanopowder is one of the well-known synthetic materials in the modern nanotechnology field. It has many interesting, lucrative and salient properties. These characters are attracting the researchers towards to exploit this material in variety of applications from energy to environmental. It is a highly sensitive and excellent photo-catalyst material. So, it can be used in gas sensors, in water splitting to generate hydrogen, and in waste water treatment to degrade the organic pollutants. It is soluble in ethanol, ethylene glycol and chloroform. TiO2 nanopowder is prepared by many methods such as sol-gel method, chemical vapour deposition, hydro-thermal, micro-emulsion etc. However, low cost and large scale synthesis of nanoparticles for commercial applications are the major challenges in the present day scenario. Mechanical milling is a simple method to prepare nanopowder where milling time plays very important role. The milling time may vary from 0 to 60 hour. The crystallinity, phase, size, shape and surface features are some of the factors affected by the milling process. For the preparation of TiO2 nanomaterial, the mechanical milling is more advantageous than other methods. It is a low cost, non toxic method which offers high chemical stability. The finely grinded TiO2 nano powder offers shiny surface and brilliant colours. Milling of TiO2 is done for size reduction. Doping of TiO2 is done to improve the efficiencies and to minimize drawbacks.

cond-mat.mtrl-sci

Extracellular biosynthesis of silver nanoparticles from Plant Growth Promoting Rhizobacteria Pseudomonas sp

Development of reliable and eco-friendly processes for synthesis of metallic nanoparticles is an important step in the field of application of nanotechnology. In the present study, extracellular synthesis of silver nanoparticles using culture supernatant of plant growth promoting rhizobacterium, Pseudomonas sp.ARS22. The biosynthesis of AgNPs by Pseudomonas sp.ARS22 was monitored by UVvisible spectrum that showed the surface plasmon resonance peak at 410 nm, an important characteristic of AgNPs. Furthermore, the morphological, elemental, functional and thermal characterization of arsAgNPs was carried out using the electron and atomic microscopies, FTIR spectroscopy and Atomic Force microscopy, respectively. The arsAgNPs were spherical in shape. The DebyeScherrer equation was used to calculate particle sizes and the silver nanoparticles of approximate size 10 to 30 nm were observed. The process of reduction is extracellular, which makes it an easier method for the synthesis of silver nanoparticles.

cond-mat.mtrl-sci

Innovation of Superparamagnetism in Lead Nanoparticles

This work reports, some of the features related to the room temperature superparamagnetic behaviours of lead nanoparticles. Such behaviours have not been discussed elaborately, in any literatures, so far. It is obvious from our studies that the superparamagnetic behaviours of Pb nanoparticles are surprising behaviours, since bulk Pb has diamagnetic behaviours. Hysteresis curve from Vibrating Sample Magnetometer study of Pb nanopowder (metal) serves some new observations. The successful calculations of values like magnetic size, saturation magnetization, coercive field, and remanent magnetism confirm its superparamagnetic nature and explore its potential application in various industries. This work throws some light on and helps further research.

cond-mat.mtrl-sci

Lead Nanopowder as Advanced Semi-Conductor, An Insight

This work reports aspect related to semi-conducting nature of nano-sized particles of lead. This attempt finds its semiconducting behaviors elaborately and such advanced insight has so far not been said in literatures. New findings of Pb nanopowder (metal) by optical, fluorescence, cyclic voltammetry and four probe studies are presented in this study. UV-Vis analysis confirms the nano nature of the sample i.e. 5 nm and SPR peak confirms its metallic nature. The successful calculations of band gap, temperature dependent resistance value confirm its semi-conducting nature and explore its potential application in various industries. This work throws some light on and helps further research.

physics.gen-ph

Titanium dioxide (TiO2) Nanoparticles XRD Analyses: An Insight

This work reports aspect related to nano-sized particles of tetragonal anatase phase Titania. This approach is simple, faster, Eco-friendly, cost effective and suitable for large scale production. X-Ray Diffraction studies analyze particles size. It is found to be 74 nm and specific surface area is 19.16m2g-1. Morphology index (MI) derived from FWHM of XRD data explains the interrelationship of particle size and specific surface area. It is observed that MI has direct relationship with particle size and an inverse relationship with specific surface area. This work throws some light on and helps in the production line of Titania nano-particles.

physics.chem-ph

Chemical Precipitation Synthesis of Ferric Chloride Doped Zinc Sulphide Nanoparticles and Their Characterization Studies

Nanoparticles of Ferric Chloride doped ZnS has been synthesized by simple chemical precipitation method and characterized by XRD, SEM, UV-Vis analysis, Differential Thermal Analysis, Thermo Gravimetric Analysis and Differential Scanning Calorimetry. XRD patterns of the samples reveal particle size, specific surface area and the formation of cubic structure. The SEM images show that the cauliflower likes structure. Optical band gap values have been obtained from UV-Vis absorption spectra. It has also been found that energy band gap (Eg) increases with the increase in molar concentration of reactant solution. Thermal analysis measurement of the prepared sample shows that the thermal stability of pure ZnS is decreased due to increase in Ferric Chloride concentration. Undoped ZnS is more thermal stable when compared to FeCl3 doped ZnS.

physics.chem-ph

Konjac Bio-Molecules Assisted, Rod-Spherical shaped Lead Nano Powder Synthesized by Electrolytic Process and Its Characterization Studies

Synthesis and structural characterization of Pb nanoparticles by electrolysis using a bioactive compound - konjac aqueous extract is the main aim of this study. This method is a unique, novel, low cost and double-step procedure with good reproducibility and has not been used for nanoparticles preparation so far. Konjac extract has been added to prevent the oxidation of Pb nanoparticles. Also the synthesized nanoparticles have been dried in open air to observe their stability. Various types of characterization tools like XRD, SEM, Particle Size Analyzer, TEM-EDS, DSC, AAS and FT-IR have been utilized to study characters of the end product. Anti-bacterial Studies has also been done. After completion of synthesis process that we have made an attempt to change the shape of the synthesized nanoparticles by the influence of sunbeams and to find the effects of the sunlight on nanomaterials.

physics.chem-ph

Chemical Capping Synthesis of Nickel Oxide Nanoparticles and their Characterizations Studies

This work reports aspect related to chemical capping synthesis of nano-sized particles of nickel oxide. It is a simple, novel and cost effective method. The average particle size, specific surface area, crystallinity index are estimated from XRD analysis. The structural, functional groups and optical characters are analyzed with using of SEM, FTIR and UV- visible techniques. XRD studies confirm the presence of high degree of crystallinity nature of nickel oxide nanoparticles. Their particle size is found to be 12 nm and specific surface area (SSA) is 74m2 g-1. The optical band gap energy value 3.83ev has also been determined from UV-vis spectrum.

physics.chem-ph

Chemical Synthesis of Nano-Sized particles of Lead Oxide and their Characterization Studies

The quantum dots of semiconductor display novel and interesting phenomena that have not been in the bulk material. The color tunability is one of the most attractive characteristics in II-VI semiconductor nanoparticles such as CdS, ZnS, CdSe, ZnSe and PbO. In this work, the semiconductor lead oxide nanoparticles are prepared by chemical method. The average particle size, specific surface area, crystallinity index are estimated from XRD analysis. The structural, functional groups and optical characters are analyzed with using of SEM, FTIR and UV- Visible techniques. The optical band gap value has also been determined.

physics.gen-ph

Nano sized Powder of Jackfruit Seed: Spectroscopic and Anti-microbial Investigative Approach

This work reports aspect related to nano-sized particles of jackfruit seed. FTIR spectrum was recorded for functional groups analysis and EDAX analysis was done to identify the various elements of the sample. Both FTIR and EDAX analysis results indicated the presence of Starch. FTIR analysis confirmed the availability of anti-microbial Sulphur derivatives compounds. Microbiology assay found that jackfruit seed nanoparticles were effective against Escherichia coli and Bacillus megaterium bacteria. This work also investigated about the dual-function of the sample i.e. food ingredients possessing antimicrobial activities. Specific surface area of bacteria analysis revealed that it played a major role while on reactions with jackfruit seed nanoparticles.

physics.gen-ph

Electrolytic Synthesis and Characterizations of Silver Nanopowder

This work reports a simple, novel, cost effective and eco-friendly electrolytic synthesis of silver nanoparticles using AgNO3 as metal precursor. The synthesis rate is much faster than other methods and this approach is suitable for large scale production. They are characterized by XRD, SEM and FT-IR techniques to analyze size, morphology and functional groups. XRD studies reveal a high degree of crystallinity and monophasic Ag nanoparticles. Their particle size is found to be 24 nm and specific surface area (SSA) is 24 m2/g. Analysis of Ag nanoparticles SSA reports that increasing their SSA improves their antibacterial actions. Microbiology assay founds that Ag nanoparticles are effective against E.coli and B.megaterium bacteria. SSA of bacteria analysis reveals that it plays a major role while reacting with antimicrobial agents.

physics.gen-ph

Studies of Copper Nanoparticles Effects on Micro-organisms

We discuss about the antibacterial activities of copper nanoparticles on both Gram negative and Gram positive bacteria in this investigation. First time, we increase its antibacterial activities by using electrical power while on electrolysis synthesis and it is confirmed from its more antibacterial activities (For Escherichia coli bacteria). We investigate the changes of surface area to volume ratio of copper nanoparticles prepared in two different methods and its effects on antibacterial activities. We note that slight change of surface area to volume ratio results in the enhancement of its antibacterial activities.

physics.gen-ph

An Insight Analysis of Nano sized powder of Jackfruit Seed

The preparation of biodegradable nanomaterials by blending starch nanocrystals with various polymer matrices are the most active research. This work reports aspect related to nano-sized particles of jackfruit seed. This approach is simple, faster, eco-friendly, cost effective and suitable for large scale production. X-Ray Diffraction studies analyze particles size, morphology, type of starch and degree of crystallinity. The particle size is found to be 12nm, specific surface area is 625 m2g-1, contains A-type starch and 32% degree of crystallinity. A morphology index (MI) is developed from FWHM of XRD data to understand interrelationship of particle size and specific surface area. MI range is from 0.50 to 0.74. It is correlated with the particle size and specific surface area. It is observed that MI has direct relationship with particle size and an inverse relationship with specific surface area.

physics.gen-ph

Anti-bacterial Studies of Silver Nanoparticles

We discuss about the antibacterial activities of Silver nanoparticles and compare them on both Gram negative and Gram positive bacteria in this investigation. The activities of Silver nanoparticles synthesized by electrolysis method are more in Gram (-) than Gram (+) bacteria. First time, we increase its antibacterial activities by using electrical power while on electrolysis synthesis and it is confirmed from its more antibacterial activities (For Escherichia coli bacteria). We investigate the changes of inner unit cell Lattice constant of Silver nanoparticles prepared in two different methods and its effects on antibacterial activities. We note that slight change of the lattice constant results in the enhancement of its antibacterial activities.

physics.gen-ph

X-Ray Diffraction Studies of Copper Nanopowder

Copper nanopowder preparation and its X-Ray diffraction studies are reported in this paper. Electrolytic cathode deposition method is simple and cheapest process for its preparation. Copper nanopowder has been prepared from aqueous copper sulphate solution. Wide range of experimental conditions has been adopted in this process and its X-Ray diffraction characterizations have been studied. The results confirming copper nanopowder with size below 30 nm. Uniformed size Copper nanopowder preparation, in normal room temperature is importance of this study.

physics.gen-ph