Ashutosh Tiwari
Abstract
The Advanced Materials Series (AM series) intends to provide recent advancements of the fascinating field of advanced materials science and technology, particularly in the area of structure, synthesis and processing, characterization, advanced-state properties and applications. It has about 30 volumes ...
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The Advanced Materials Series (AM series) intends to provide recent advancements of the fascinating field of advanced materials science and technology, particularly in the area of structure, synthesis and processing, characterization, advanced-state properties and applications. It has about 30 volumes till 2016. The volumes cover theoretical and experimental approaches of molecular device materials, biomimetic materials, hybrid-type composite materials, functionalized polymers, supramolecular systems, information- and energy-transfer materials, bio based and biodegradable or environmental friendly materials. Each volume is devoted to one broad subject and the multi-disciplinary aspects are drawn out in full. The books are comprehensive and represents the cutting edge of science. They are written for a broad readership including researchers and students from diverse backgrounds including chemistry, physics, materials science & engineering, medical science, pharmacy, biotechnology and biomedical engineering.
Avishek Das; Ajay Kushwaha; Nakul Raj Bansal; Vignesh Suresh; Sanghamitra Dinda; Sanatan Chattopadhyay; Goutam Kumar Dalapati
Abstract
In the present work, cupric oxide (CuO) nanoparticle (NP) thin films were synthesized on glass by combination of sputter and chemical bath deposition technique. The CuO seeds were deposited by using radio frequency (RF) sputter technique at room temperature. CuO nanoparticles were prepared by chemical ...
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In the present work, cupric oxide (CuO) nanoparticle (NP) thin films were synthesized on glass by combination of sputter and chemical bath deposition technique. The CuO seeds were deposited by using radio frequency (RF) sputter technique at room temperature. CuO nanoparticles were prepared by chemical bath deposition. Effect of solute molar concentration (0.02 to 0.04M) and annealing temperature (at 400°C) on nanoparticles size and distribution were studied. The average size of nanoparticles is small in lower molar concentration, which is restructured after annealing to form dense film with relative smaller size nanoparticles. The work opens up new route to synthesize CuO nanorticle thin films for different applications.
Divyanshu Bhatnagar; Ratnamala Chatterjee
Abstract
BaBiO3 (BBO) particles were successfully synthesized through solid-state route, to provide better understanding of its transport properties, which is not well studied yet. X-ray diffraction (XRD) measurement confirmed that the particles were crystallized with monoclinic structure in single phase. The ...
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BaBiO3 (BBO) particles were successfully synthesized through solid-state route, to provide better understanding of its transport properties, which is not well studied yet. X-ray diffraction (XRD) measurement confirmed that the particles were crystallized with monoclinic structure in single phase. The Raman spectrum of BBO sample revealed the existence of two different Bi sites (the octahedral BiO6/3 and the triangular pyramidal BiO4/2 cluster). Subsequently, the observation of low resolution and lattice scale imaging through high resolution transmission electron microscope (HRTEM) indicated the formation of monoclinic BBO particles of size ~ 50-60 nm. The ring pattern obtained from selected area electron diffraction (SAED) inveterate polycrystalline nature of the sample and calculated structural parameters well harmonized with XRD results. As expected, BBO showed semiconducting behavior with resistivity of ~ 3.8 kΩ-cm at room temperature along with an excellent NTC (negative temperature coefficient) thermistor characteristic. The dielectric measurements and impedance spectroscopy studies reveal that BBO exhibit two typical characteristics, i.e., diffuse phase transition and frequency dependent dielectric maxima, of relaxor oxides; with negative dielectric constant above 550 K.
Somdatta Paul; Avishek Das; Mainak Palit; Satyaban Bhunia; Anupam Karmakar; Sanatan Chattopadhyay
Abstract
In this work, a comparative performance analysis of ZnO nanowires grown by following single- and double-step techniques on (100) p-Si substrate has been conducted. High-quality ZnO nanowires with c-axis orientation and perfect crystalline structures with appropriate chemical stoichiometry have been obtained ...
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In this work, a comparative performance analysis of ZnO nanowires grown by following single- and double-step techniques on (100) p-Si substrate has been conducted. High-quality ZnO nanowires with c-axis orientation and perfect crystalline structures with appropriate chemical stoichiometry have been obtained from both the approaches. The areal density of the nanowires grown from double step approach is almost twice the nanowires grown by employing the single step approach. Histogram analysis shows that the diameter and height of majority of the single-step grown nanowires are ~370nm and ~2.45µm, and for the double step grown nanowires these are ~210 nm and ~2.16 µm, respectively. The bandgap values of the single-step and double-step grown nanowires are measured to 3.19eV and 3.26eV, respectively. The current-voltage characteristics of p-Si/n-ZnO diodes indicate that the forward current is contributed by both the electrons and holes and the relevant cut-in voltages are measured to be 0.5V and 2.5V, respectively.
Abdul Rauf Khaskheli; Saba Naz; Razium Ali Soomro; Faruk Ozul; Abdalaziz Aljabour; Nazar Hussain Kalwar; Abdul Waheed Mahesar; Imren Hatay Patir; Mustafa Ersoz
Abstract
This report demonstrates a facile and green fabrication method for the nickel nanoparticles using L-lysine as an efficient protecting agent. The application of green amino acid (L-lysine) enabled formation highly spherical and well-dispersed nanoparticles with average diameter in the range of 10 ±2.5 ...
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This report demonstrates a facile and green fabrication method for the nickel nanoparticles using L-lysine as an efficient protecting agent. The application of green amino acid (L-lysine) enabled formation highly spherical and well-dispersed nanoparticles with average diameter in the range of 10 ±2.5 nm. UV-Vis spectroscopy was used as a primary tool to elaborately study and optimize the necessary experimental condition for the developed synthetic protocol. Fourier transform infrared spectroscopy (FTIR) was used to confirm the surface protection of Ni NPs via L-lysine molecules whereas; atomic force microscopy (AFM) and scanning electron microscopy (SEM) provided morphological and topographical view of the as-synthesized Ni NPs. In addition, small angle X-ray scattering (SAXS) and X-ray diffraction (XRD) were used to evaluate compositional characteristics of fabricated L-lysine protected Ni NPs. The as-synthesized Ni NPs demonstrated excellent catalytic potential when utilized as heterogeneous catalyst for reduction of methylene Blue (MB) in the presence of sodium borohydride (NaBH4). The observed catalytic reaction was determined to follow pseudo first order kinetics with rate constant (K) and turn over frequency (TOF) determined to be 0.0224 and TOF value of 0.00411 s -1 respectively.
Kuldeep Chand Verma; R.K. Kotnala
Abstract
We reported the Core/Shell structures of CoFe2-xCexO4 (CFCeO) nanoparticles were prepared by a chemical combustion method. The Rietveld refinement of X-ray diffraction pattern results into CoFe2O4 spinel structure and thevariation in lattice parameters have been found with doping of Ce ions. Transmission ...
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We reported the Core/Shell structures of CoFe2-xCexO4 (CFCeO) nanoparticles were prepared by a chemical combustion method. The Rietveld refinement of X-ray diffraction pattern results into CoFe2O4 spinel structure and thevariation in lattice parameters have been found with doping of Ce ions. Transmission Electron Microscopy analysis has shown Core/Shell type nanoparticles. The stoichiometric composition of Co, Fe, Ce and O atoms has been analyzed through X-ray fluorescence elemental detection. Fourier transform infrared spectra could detect organic extent, tetrahedral (Fe-O), octahedral (Fe(Ce)-O-Co) and lattice disorder in CFO nanoparticles with Ce doping. Defects related oxygen vacancies are analyzed in Photoluminescence emission spectra. The room temperature magnetic measurement of CFO nanoparticles is highly influenced with Ce ions. The magnetic interactions are antiferromagnetic at room temperature that confirmed by zero field cooling and field cooling magnetic measurements at 100 Oe. However, the spin glass and ferromagnetic clustered growth may also exist in CFCeO samples that reduce room temperature ferromagnetism. The dielectric measurement indicates polarization up to higher frequency region that enhanced with Ce ions.
Yasenchuk Yu. F.; Artyukhova N. V.; Chekalkin T. L; Anikeev S. G.; Kim Ji-Soon; Kang Ji-Hoon; Gunther V. E
Abstract
Modern medical technologies have developed many new devices that can be implanted into humans to repair, assist or take the place of diseased or defective bones, arteries and even organs. The materials, especially porous ones, used for these devices have evolved steadily over the past twenty years with ...
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Modern medical technologies have developed many new devices that can be implanted into humans to repair, assist or take the place of diseased or defective bones, arteries and even organs. The materials, especially porous ones, used for these devices have evolved steadily over the past twenty years with TiNi-based alloys replacing stainless steels and titanium. The aim of the paper is to presents results for examination of porous TiNiMoCo-based alloy intended further to be used in clinical practice. Porous TiNi-based alloys showing shape memory effect were obtained by the methods of reaction and diffusion sintering with cobalt additives. From the results of the analysis of temperature dependences determined by the measurement of electrical resistivity and shape memory effect test, the effect of cobalt addition on the martensitic transformations in sintered body is described. The addition of cobalt during reaction and, especially, diffusion sintering, results in a decrease in the internal stresses in the TiNi phase. The addition of Co more than 1 at. % led to precipitation hardening of the alloy. Cobalt at concentrations studied in the work led to suppression of martensitic phase transformation.
Nilesh H. Naik; Javaid Athar; Nirmala Sikder; Arun K. Sikder
Abstract
The energetic plasticizers like azidopolyester (APE) in Hydroxy Terminated Poly-Butadiene (HTPB) binder formulations are known to enhance the ballistic properties of explosive formulations. The pyrolysis gas chromatography-mass spectrometry (Py-GCMS) studies were carried out on HTPB with APE to get insight ...
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The energetic plasticizers like azidopolyester (APE) in Hydroxy Terminated Poly-Butadiene (HTPB) binder formulations are known to enhance the ballistic properties of explosive formulations. The pyrolysis gas chromatography-mass spectrometry (Py-GCMS) studies were carried out on HTPB with APE to get insight of the decomposition pathway of HTPB. Based on the results, decomposition mechanism is proposed for uncured and cured HTPB, with and without energetic plasticizer. It has been observed that the decomposition mechanism of cured HTPB is similar to the pure HTPB polymer. In case of energetic plasticizer based composition, it is seen that APE triggers the decomposition which results in the formation of monomers, dimer and oligomers. Overall, the study helps in understanding the role of energetic plasticizer on improving the performance of the binder composition
Jimena S. Gonzalez; Yanina N. Mart
Abstract
Polyvinyl alcohol (PVA) and polyvinyl alcohol-pectin (PVA-P) cryogels are potential devices for wound healing. These materials have advantages over commercial wound dressings such as: retaining an appropriate level of moisture around wound and gas permeability and antibacterial properties. In a previous ...
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Polyvinyl alcohol (PVA) and polyvinyl alcohol-pectin (PVA-P) cryogels are potential devices for wound healing. These materials have advantages over commercial wound dressings such as: retaining an appropriate level of moisture around wound and gas permeability and antibacterial properties. In a previous work, PVA-P cryogels containingan antibiotic and an enzyme (enrofloxacin and keratinase respectively) have been developed with promising results. In the present work, an exhaustive chemical, morphological and physical characterization of these films was carried out in order to explain the effect of incorporation of pectin into PVA matrix. The results show that the presence of pectin in PVA cryogel increase the size of PVA nanodomains determined by XRD patterns indicating an interaction between both PVA and pectin polymers. PVA nanodomains and crystallinity degree changed when enrofloxacin and keratinase were immobilized into PVA-P cryogels determined by SAXS and DSC analysis. These results suggest a good incorporation of both drugs into the polymeric matrix. A model involving the complex formation between the enzyme and enrofloxacin allocated through and between PVA nanodomains is proposed and it correlates well with results obtained in previous work where enrofloxacin kinetic release was found retarded by the presence of keratinase in the cryogels.
Rohan Dasa; Kaushik Guptaa; Kuntal Janaa; Arabinda Nayakb; Uday Chand Ghosha
Abstract
Strontium-zirconium bimetal oxide (SrZrO3) samples at nanophase were prepared by chemical precipitation-annealnation method, and characterized by powder X-ray diffraction (XRD), UV-Vis and FTIR spectroscopies and field emission scanning electron microscopy (FESEM). Grain size (nm) of the SrZrO3 samples ...
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Strontium-zirconium bimetal oxide (SrZrO3) samples at nanophase were prepared by chemical precipitation-annealnation method, and characterized by powder X-ray diffraction (XRD), UV-Vis and FTIR spectroscopies and field emission scanning electron microscopy (FESEM). Grain size (nm) of the SrZrO3 samples prepared by annealing at 650°C (S650), 850°C (S850) and 1050°C (S1050), respectively, were 55-60, 45-47 and 25-32. The optical band gaps (eV) estimated are to be 4.71 and 4.83 of S850 and S1050, respectively. Both FTIR and XRD studies confirmed the formation of SrZrO3 phase. FESEM images of the S850 sample showed the presence of agglomerated nano spheres with irregular surface morphology. Temperature dependent ac-conductivity analyses of S850 sample showed semiconducting behavior with low thermal activation energy (28 meV). Hopping conduction of charge carriers had been concluded considering the relaxation processes associated with the grain and grain boundaries of the sample. Dielectric behavior of S850 sample was confirmed from considerably high dielectric constant value (~ 140) and low dielectric loss (~ 0.6) at 100 Hz. Cyclic voltammograms suggested the pseudo-capacitive behavior of as-prepared S850 and S1050 samples. Thus as-prepared SrZrO3 nanophase could be used as High-K dielectric material in various applications.
C. Stella; N. Soundararajan; K. Ramachandran
Abstract
Chunk shaped ZnO/Co3O4 nanocomposites for different concentrations of 90:10 (Z9C1), 70:30 (Z7C3), and 50:50 (Z5C5) were successfully synthesized by co-precipitation method. The structure, morphology, and elemental composition of the prepared samples were characterized by X-ray diffraction (XRD), scanning ...
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Chunk shaped ZnO/Co3O4 nanocomposites for different concentrations of 90:10 (Z9C1), 70:30 (Z7C3), and 50:50 (Z5C5) were successfully synthesized by co-precipitation method. The structure, morphology, and elemental composition of the prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS), respectively which confirm the formation of ZnO/Co3O4nanocomposites. Raman analysis confirmed the presence of oxygen vacancies in the Z5C5 sample. The magnetic studies revealed that, the Z5C5 nanocomposite exhibit room temperature ferromagnetism. The gas sensing property clearly confirm the response of Z5C5 sensor which was as high as 5.6%, about 4 times higher than Z9C1 sample. The enhancement of gas sensing property is due to the collective contribution of smaller particle size, oxygen vacancies, and the formation of more p-n hetero junction in Z5C5 nanocomposite.
Aftab H. Mondal; Mudsser Azam; Mohammad T. Siddiqui; Qazi M. Rizwanul Haq
Abstract
In the present study extracellular synthesis of silver nanoparticles (AgNPs) was achieved using cultural supernatant of bacterial isolate Aeromonas dhakensis AS3. Biosynthesis of AgNPs was completed within 120 min by incubating cell free supernatant with silver nitrate solution under illumination. Brown ...
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In the present study extracellular synthesis of silver nanoparticles (AgNPs) was achieved using cultural supernatant of bacterial isolate Aeromonas dhakensis AS3. Biosynthesis of AgNPs was completed within 120 min by incubating cell free supernatant with silver nitrate solution under illumination. Brown color appearance of solution due to surface plasmon resonance (SPR) and absorption maxima centered at 405 nm was indicated formation of AgNPs. Fourier transform infrared spectroscopy (FTIR) spectrum analysis revealed the presence and association of possible biomolecules with AgNPs during synthesis. Atomic force microscopy (AFM), Field emission scanning electron microscopy (FE-SEM) and High resolution transmission electron microscopy (HR-TEM) showed spherical nanoparticles with an average size of 5 nm. X-ray diffraction (XRD) and Energy Dispersive X-ray (EDX) spectrum confirmed crystallinity and purity of AgNPs. The synthesized AgNPs was found to have significantly independent as well as combined activity against multidrug resistant extended spectrum β-lactamases (ESBLs) producing Acinetobacter junii, E.coli and Klebsiella spp. harboring TEM and/or CTX-M genes. This work demonstrates the possible use of biosynthesized AgNPs to combat ESBLs producing pathogens.
Nidhi Chauhan; Utkarsh Jain
Abstract
The glucose level measurement in the blood of diabetic patients without significant variations is important. The level of glycated hemoglobin (HbA1c) in the blood provides an authentic tool for glucose level measurement. In our study, a biosensing system established on properly aligned single-crystal ...
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The glucose level measurement in the blood of diabetic patients without significant variations is important. The level of glycated hemoglobin (HbA1c) in the blood provides an authentic tool for glucose level measurement. In our study, a biosensing system established on properly aligned single-crystal zinc oxide (ZnO) nanorods structures grown on indium-tin oxide coated glass plate (ITO) electrode. ZnO nanorods were immobilized with fructosyl amino-acid oxidase (FAO) enzyme through physical adsorption integrated with cross linking molecules N-5-azido-2-nitro-benzoyloxysuccinimide (ANB-NOS). Whole blood samples were first hemolyzed & then properly digested with protease prior to measuring the HbA1c through the sensor. This enzyme biosensor reported an optimum response at +0.2 V. This biosensor displayed a significant sensitivity and detection limit (0.1μM), fast response time (4s) and wide linear range (from 0.1 to 2000 μM). The enzyme/working electrode is stable for about 4 months, when kept at 4 oC. This recommended biosensor method may apply for detecting HbA1c in blood samples obtained from apparently healthy as well as diabetic patients.
Somit Kumar Singh; Ananda Murthy H. C; Vandana Singh
Abstract
In the present investigation, the remediation of mercury by using the gum acacia-silica composite as an adsorbent has been studied. Experiments revealed optimum parameters which were found to be pH 6, contact time 2 hours, Hg(II) concentration of 100 ppm, reflux temperature 30 0 C and adsorbent dosage ...
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In the present investigation, the remediation of mercury by using the gum acacia-silica composite as an adsorbent has been studied. Experiments revealed optimum parameters which were found to be pH 6, contact time 2 hours, Hg(II) concentration of 100 ppm, reflux temperature 30 0 C and adsorbent dosage of 50 mg. The experimental data was subjected to modeling using the Langmuir and Freundlich isotherms. It was found that the data very well fitted to the Freundlich model. The pseudo second order kinetics confirms chemisorption with rate constant 3.1 × 10-4 gmg-1min-1. The calculated thermodynamic parameters (?G 0 , ?S 0 , ?H 0 ) revealed the exothermic and spontaneous nature of adsorption process at the solid–solution interface. The adsorbent could be recycled for six successive cycles with 31.5% loss in its efficiency. The adsorbent is found to be highly effective and economical for mercury remediation from water.
Rishikesh Kumar; Saravanan Muthiah; Avinash K. Singh; Ajay Dhar
Abstract
We report the synthesis of both n-type Mg2Si and p-type MnSi1.73 using reaction sintering employing spark plasma sintering (SPS) process. The thermoelectric device was fabricated using these synthesized thermoelectric materials having a ZT value of ~ 0.7 for n-type Mg2Si and ~ 0.55 for p-type MnSi1.73. ...
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We report the synthesis of both n-type Mg2Si and p-type MnSi1.73 using reaction sintering employing spark plasma sintering (SPS) process. The thermoelectric device was fabricated using these synthesized thermoelectric materials having a ZT value of ~ 0.7 for n-type Mg2Si and ~ 0.55 for p-type MnSi1.73. The two design combination of unicouple thermoelectric devices were fabricated; nickel contacts at hot & cold ends in first device and graphite contact at hot end & nickel contact at cold end in another device. The device comprised of n-type Mg2Si & p-type MnSi1.73 legs each with dimensions of 4 × 4 × 10 mm. The voltage and current output characteristics of this thermoelectric device were evaluated at temperature gradient between hot and cold ends in the range of 50 to 350 K. The maximum open circuit voltage output (~135mV) and maximum current output (~200 mA) from nickel contacts device were obtained at ?T ≈350 K, which would be much higher at elevated operating temperatures and employing several such thermoelectric couples.