ADVANCES IN BASIC SCIENCE (ICABS 2019)最新文献

{"title":"Mechanistic investigation into CO oxidation catalyzed by Au5 gold cluster","authors":"S. Saini, J. Yadav, J. Parkash","doi":"10.1063/1.5122634","DOIUrl":"https://doi.org/10.1063/1.5122634","url":null,"abstract":"The most studied reaction catalyzed by gold nanostructures is CO oxidation. The majority of the studies report Langmuir-Hinshelwood mechanism for CO oxidation. In this report, we present density functional theory results of CO oxidation catalyzed by Au5 gold nanocluster. Our results suggest that CO oxidation reaction proceeds via both mechanisms; Langmuir-Hinshelwood as well as Eley-Rideal mechanism.The most studied reaction catalyzed by gold nanostructures is CO oxidation. The majority of the studies report Langmuir-Hinshelwood mechanism for CO oxidation. In this report, we present density functional theory results of CO oxidation catalyzed by Au5 gold nanocluster. Our results suggest that CO oxidation reaction proceeds via both mechanisms; Langmuir-Hinshelwood as well as Eley-Rideal mechanism.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74305604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biofriendly and green biocomposites based on poly (ε-caprolactone): Post-yield fracture, crystallization, rheological and micromechanical behaviors","authors":"A. Tripathi, S. N. Maiti, Josemon Jacob, Jyoti Singh, P. Chakraborty","doi":"10.1063/1.5122403","DOIUrl":"https://doi.org/10.1063/1.5122403","url":null,"abstract":"In this study low cost biodegradable fillers was incorporated as reinforcing filler into poly(e-caprolactone (PCL) matrix by melt compounding (0-35 wt. %) in a twin screw extruder. The prepared biocomposites were investigated for their Thermomechanical, melt rheological, fracture, and crystallization behaviors. The essential work of fracture (we) is reduced on incorporation of GTS while increase in the non-essential work of fracture (βwp) is observed. The composites with 20 wt% of GTS showed 121% increase in the βwp due to reduced interspherulitic region while 35 % decrease in the parameter is registered for highest GTS content (35 wt. %). From the DSC measurements, sharp decrease in crystallinity was observed for all the compositions studied. The crystallization behavior of PCL in presence of varying concentrations of natural fillers ranging from 5 to 35 wt% is also studied. Various crystallization parameters were studied by DSC at four different cooling rates and these parameters were analysed employing Ozawa, Jeziorny and Liu models. Kissinger method was used to estimate the activation energy (ΔE) of the PCL/GTS composites. The ΔE results suggested that the speed of crystallization was inhibited by GTS particles.In this study low cost biodegradable fillers was incorporated as reinforcing filler into poly(e-caprolactone (PCL) matrix by melt compounding (0-35 wt. %) in a twin screw extruder. The prepared biocomposites were investigated for their Thermomechanical, melt rheological, fracture, and crystallization behaviors. The essential work of fracture (we) is reduced on incorporation of GTS while increase in the non-essential work of fracture (βwp) is observed. The composites with 20 wt% of GTS showed 121% increase in the βwp due to reduced interspherulitic region while 35 % decrease in the parameter is registered for highest GTS content (35 wt. %). From the DSC measurements, sharp decrease in crystallinity was observed for all the compositions studied. The crystallization behavior of PCL in presence of varying concentrations of natural fillers ranging from 5 to 35 wt% is also studied. Various crystallization parameters were studied by DSC at four different cooling rates and these parameters were analysed employing...","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77718119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DFT+U study of small ZnO nanoclusters","authors":"M. Sharma, D. Mishra","doi":"10.1063/1.5122485","DOIUrl":"https://doi.org/10.1063/1.5122485","url":null,"abstract":"We present a DFT+U study of the structural and electronic properties for small ZniOi nanoclusters, where i = 2 to 9. The Hubbard model (DFT+U) provides an on-site Coulomb correction to remedy some of the drawbacks of conventional GGA functionals, such as the underestimation of band-gaps. The Hubbard corrections were applied to both Zn-3d and O-2p orbitals resulting in improved predictions of properties. DFT+U provides an inexpensive way to accurately reproduce the measured properties as compared to the more expensive hybrid functionals. This plays a huge role in the development of High-Throughput Quantum-Mechanics (HTQM).We present a DFT+U study of the structural and electronic properties for small ZniOi nanoclusters, where i = 2 to 9. The Hubbard model (DFT+U) provides an on-site Coulomb correction to remedy some of the drawbacks of conventional GGA functionals, such as the underestimation of band-gaps. The Hubbard corrections were applied to both Zn-3d and O-2p orbitals resulting in improved predictions of properties. DFT+U provides an inexpensive way to accurately reproduce the measured properties as compared to the more expensive hybrid functionals. This plays a huge role in the development of High-Throughput Quantum-Mechanics (HTQM).","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84993229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-focusing of asymmetric cosh-Gaussian laser beams in weakly ionized collisional magnetized plasma","authors":"B. D. Vhanmore, A. T. Valkunde, T. U. Urunkar, K. M. Gavade, S. Patil, M. Takale","doi":"10.1063/1.5122477","DOIUrl":"https://doi.org/10.1063/1.5122477","url":null,"abstract":"In the present paper, we have exploited the self-focusing of asymmetric cosh-Gaussian (ChG) laser beams in weakly ionized collisional magnetized plasma. Differential equations for the beam-width parameters in two transverse dimensions of the beam are obtained by using Wentzel-Kramers-Brillouin (WKB) and paraxial approximations through parabolic equation approach. The final results of numerical computation are presented in the form of graphs and discussed. It is found that enhanced self-focusing is observed with reduction in self-focusing length by increasing the decentred parameters in both the dimensions of the beam.In the present paper, we have exploited the self-focusing of asymmetric cosh-Gaussian (ChG) laser beams in weakly ionized collisional magnetized plasma. Differential equations for the beam-width parameters in two transverse dimensions of the beam are obtained by using Wentzel-Kramers-Brillouin (WKB) and paraxial approximations through parabolic equation approach. The final results of numerical computation are presented in the form of graphs and discussed. It is found that enhanced self-focusing is observed with reduction in self-focusing length by increasing the decentred parameters in both the dimensions of the beam.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80821751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural, optical and electrical properties of BaTiO3 – NiFe2O4 based multifunctional composites","authors":"Mehjabeen Khan, A. Mishra, J. Shukla, P. Sharma","doi":"10.1063/1.5122593","DOIUrl":"https://doi.org/10.1063/1.5122593","url":null,"abstract":"The composites with composition of (1-x)BaTiO3(BTO) – (x)NiFe2O4(NF) with x=0.25 and 0.75 were synthesized by sintering the mixtures of highly ferroelectric and highly magnetostructive magnetic phaseobtained by auto combustion method. Structural study using Reitveld refinement of X-ray diffraction (XRD) pattern indicated a tetragonal structure (space group P4mm) for BTO phase while to that NF compound crystallizes in cubic structure (space group Fd3m). XRD pattern show that BTO and NF phase exists independently in NiFe2O4 doped composites without the presence of undesirable phases. The energy band gap (Eg) of both the composites have been measured using Diffuse Reflectance Spectroscopy (DRS). Band gaps are found to be 3.13 eV and 2.75 respectively for x=0.25 and 0.75. With the increase of NF ferrite phase, band gap is found to decrease. This is due to the fact that band gap value of the Nickel Ferriteis less as compared to Barium Titanate. This indicate the possibility of easy manipulation of the band gap over a range of energies by mere control of the molar ratio of phases. The electrical study of these materials were investigated using ferroelectric (P-E) loop tracer. For x=0.25 composite has shown better electrical property in comparison to other investigated composite for x=0.75. Remnant polarization and coercive field decreased with the increase of the content of magnetic phase.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83593657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gold nanoparticles in drug delivery systems: Therapeutic applications","authors":"Meena Devi, Shachi Awasthi","doi":"10.1063/1.5122562","DOIUrl":"https://doi.org/10.1063/1.5122562","url":null,"abstract":"In the present century, Nanotechnology is gaining tremendous importance due to its capability of modulating metals into their nanosize, which drastically changes the physical, chemical and optical properties of metals. These properties can be used to overcome some of the limitations found in traditional therapeutic and diagnostic agents. Functionalized Gold (Au) nanoparticles represent highly attractive and promising applications in drug delivery in special context to their unique dimensions, tunable functionalities on the surface and controllable drug release. Gold nanoparticles have unique properties which help in molecular diagnostics, therapies and as well as in devices that are used in several medical procedures. Continuing improvement in the pharmacological and therapeutic properties of drugs is driving the revolution in novel drug delivery systems. This article will review recent developments in the use of Gold nanoparticles as drug delivery systems to treat a wide variety of diseases. The purpose of this paper is to focus on therapeutic applications of gold nanoparticles while exploring their various prospectives like cancer therapy, gold nanospheres, gold nanoshells, gold nanorods, gold nanocages and photothermal therapy. The ultimate aim of this research is to open some new aspects of nanomedicine to fight and prevent diseases using atomic scale materials.In the present century, Nanotechnology is gaining tremendous importance due to its capability of modulating metals into their nanosize, which drastically changes the physical, chemical and optical properties of metals. These properties can be used to overcome some of the limitations found in traditional therapeutic and diagnostic agents. Functionalized Gold (Au) nanoparticles represent highly attractive and promising applications in drug delivery in special context to their unique dimensions, tunable functionalities on the surface and controllable drug release. Gold nanoparticles have unique properties which help in molecular diagnostics, therapies and as well as in devices that are used in several medical procedures. Continuing improvement in the pharmacological and therapeutic properties of drugs is driving the revolution in novel drug delivery systems. This article will review recent developments in the use of Gold nanoparticles as drug delivery systems to treat a wide variety of diseases. The purpose ...","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87557419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stir casting & processing of aluminum matrix composites","authors":"R. Pravin, S. Raj","doi":"10.1063/1.5122395","DOIUrl":"https://doi.org/10.1063/1.5122395","url":null,"abstract":"Aluminium Matrix Composites have potential applications in Aerospace and Automotive industries. Their light weight structure, high corrosion resistance and superior mechanical properties make them a choice candidate in higher end applications. Aluminiummatrix composites materials can be produced by many different techniques. By altering the manufacturing method, the processing and the finishing, as well as by the form of the reinforcement components added, it is possible to obtain different characteristic profiles, although the same composition and same amounts of the components are involved. This paper focuses on the processing of various aluminium alloy composites by varying different parameters using stir casting technique. Because of the presence of ceramic reinforcements, processing these metal matrix composites is challenging and requires better alternative techniques.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89140324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rare earth (Er3+) doped nickel zinc ferrite: Additional effects in structural and dielectric properties","authors":"S. Nag, D. Das, S. Mukherjee","doi":"10.1063/1.5122340","DOIUrl":"https://doi.org/10.1063/1.5122340","url":null,"abstract":"Erbium (Er3+) dopednickel zinc ferrites with generic formula Ni0.5Zn0.5ErxFe2-xO4 (with x=0, 0.025, 0.05) were synthesized by citric acid mediated sol-gel auto-combustion method. Structural and morphological characterization of the samples was respectively done by X-ray diffraction and transmission electron microscopic techniques. Fourier transform infrared spectroscopic studies of the samples were also done. Effect of Er3+ ion incorporation on the dielectric properties of the samples at room temperature over a wide frequency range (100 Hz-10 MHz) were studied by a LCR meter. Sample with erbium (x)=0.025 percentage doping with relatively higher dielectric constant and lower dielectric loss value with respect to the pure nickel zinc ferrite showed a good possibility in high frequency applications.Erbium (Er3+) dopednickel zinc ferrites with generic formula Ni0.5Zn0.5ErxFe2-xO4 (with x=0, 0.025, 0.05) were synthesized by citric acid mediated sol-gel auto-combustion method. Structural and morphological characterization of the samples was respectively done by X-ray diffraction and transmission electron microscopic techniques. Fourier transform infrared spectroscopic studies of the samples were also done. Effect of Er3+ ion incorporation on the dielectric properties of the samples at room temperature over a wide frequency range (100 Hz-10 MHz) were studied by a LCR meter. Sample with erbium (x)=0.025 percentage doping with relatively higher dielectric constant and lower dielectric loss value with respect to the pure nickel zinc ferrite showed a good possibility in high frequency applications.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83027874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A brief review on the synthesis of maghemite (γ-Fe2O3) for medical diagnostic and solar energy applications","authors":"S. Kour, R. Sharma, Rohit Jasrotia, V. Singh","doi":"10.1063/1.5122451","DOIUrl":"https://doi.org/10.1063/1.5122451","url":null,"abstract":"Magnetic nanoparticles are of great interest due to structure and composition of materials. MNP consists of cations, e.g., Fe, Ni, Co, Cr, and their oxides, such as magnetite (Fe3O4), maghemite (γ-Fe2O3), hematite (α- Fe2O3), cobalt ferrite (Fe2CoO4), and chromium dioxide (CrO2). Magnetic nanoparticles are gaining interest due to their useful electrical and magnetic properties and applications in magnetic storage, recording media, photo catalysis, and medical diagontics as well as in solar energy applications. Magnetic nanoparticles are regarded as the most practically important and useful due to its simple synthesis and the interesting magnetic characteristics of its nano-sized objects. This review summarizes recent commercial, industrial and bio-engineering applications and brief study of the methods for the preparation of magnetic nanoparticles with a control over the size, morphology and the magnetic properties.Magnetic nanoparticles are of great interest due to structure and composition of materials. MNP consists of cations, e.g., Fe, Ni, Co, Cr, and their oxides, such as magnetite (Fe3O4), maghemite (γ-Fe2O3), hematite (α- Fe2O3), cobalt ferrite (Fe2CoO4), and chromium dioxide (CrO2). Magnetic nanoparticles are gaining interest due to their useful electrical and magnetic properties and applications in magnetic storage, recording media, photo catalysis, and medical diagontics as well as in solar energy applications. Magnetic nanoparticles are regarded as the most practically important and useful due to its simple synthesis and the interesting magnetic characteristics of its nano-sized objects. This review summarizes recent commercial, industrial and bio-engineering applications and brief study of the methods for the preparation of magnetic nanoparticles with a control over the size, morphology and the magnetic properties.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83285180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dielectric properties of La2Ti2O7 ceramics","authors":"R. Swami, K. Sreenivas","doi":"10.1063/1.5122350","DOIUrl":"https://doi.org/10.1063/1.5122350","url":null,"abstract":"La2Ti2O7 ceramics prepared by solid state reaction method have been studied for their structural and dielectric properties. At room temperature (25 °C), La2Ti2O7 ceramics exhibit intrinsic dielectric response with a dielectric constant ∼ 41 and dielectric loss ∼10−2 at f = 1 MHz. Impedance spectroscopy in the frequency range 1Hz to 1 MHz reveals grain and grain boundary effects with estimated grain resistances (Rg ∼ 1.01⨉106 Ω) and grain boundary resistance (Rgb ∼ 5.4⨉106 Ω). The room temperature dc resistivity is estimated to be 5.615⨉107 Ω cm for La2Ti2O7 ceramics sintered at 1200 °C for 24 hours.","PeriodicalId":7262,"journal":{"name":"ADVANCES IN BASIC SCIENCE (ICABS 2019)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85334536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}