This document summarizes a study that synthesized nanoparticles of Y3+ substituted Ni1-x Cdx Yy Fe2-y O4 using a sol-gel autocombustion method. X-ray diffraction analysis revealed the nanoparticles had an average grain size between 12.5 to 34.8 nm and a spinel cubic structure. Ultraviolet visible spectroscopy and Fourier transform infrared spectroscopy were used to investigate the optical properties. The average band gap energy calculated using the Tauc method was 1.6294 eV, indicating the materials behaved as semiconductors. Increasing the Y3+ concentration slightly increased the lattice constant and slightly decreased the band gap energy.
Structural and Dielectric Studies of Cerium Substituted Nickel Ferrite Nano P...theijes
Cerium substituted Nickel ferrite nanoparticles with general formula NiCeXFe2-XO4 (x=0.0, 0.05, 0.1, 0.15) have been synthesized by using sol-gel method. The crystalline structure and grain size of these particles were analyzed by using XRD; the particle size ranged from 12.22nm to 17.60nm.The decrease in value of the lattice parameter with doping suggests that there is shrinkage in unit cell. The single-phase cubic spinal structure was clearly indicated by the XRD patterns of pure NiFe2O4.The XRD pattern also show that all the samples had formed the cubic single phase spinal structure. Dielectric properties have been studied in the frequency range of 1 kHz to 5 MHz. Permittivity and tangent loss (tanδ) decreases with the substitution of Ce3+ in parent crystal structure.
Synthesis and characterization of pure zinc oxide nanoparticles and nickel do...eSAT Journals
Abstract In this paper, Zinc oxide nanoparticles are synthesized by simple wet chemical precipitation method. Zinc nitrate and sodium hydroxide are used as the starting materials.Zinc oxide nanoparticles are formed at a very low temperature of the order of 800C. Nickel doped zinc oxide nanoparticles are synthesized in two steps. In first step precipitate is obtained by reduction of mixture of zinc nitrate, ferric nitrate and starch by sodium hydroxide solution while in second step the given precipitate is thermally decomposed at high temperature of the order of 4000C. The crystallinity of the synthesized nanoparticles is then confirmed by X ray diffraction spectroscopy (XRD).The elemental composition of the powder is detected by Energy Dispersive X ray spectroscopy (EDAX). The morphology of the powder is investigated by Scanning Electron Microscopy (SEM). Magnetic characterization of nickel doped zinc oxide nanoparticles is done by Squid Magnetometer. Low temperature magnetization behavior revealed ferromagnetic behavior of sample. Key Words: Zinc oxide nanoparticles, Nickel doped ZnO, Antibacterial activity, Squid magnetometer, SEM
Synthesis and Structural Characterization of Cu Substituted Ni-Zn Nano-Ferrit...IJERA Editor
The ferrite nano particles having chemical formula Ni0.2CuxZn0.8-xFe2O4 (where x=0.0 to 0.8 with step of 0.2) were synthesized by Citrate-Gel Auto Combustion method at low temperature. The synthesized powders were sintered at 500oC for 4 hours in air and characterised by XRD, SEM with EDS. XRD analysis of prepared samples were confirmed the single phase cubic spinel Structure. The crystallite size (D) of prepared ferrites were in the range of 24-73nm. The values of lattice parameter (a) decreased and X-ray density (dx) were increased with the increasing of Cu substitution. The surface morphology of the prepared samples was investigated by Scanning Electron Microscope(SEM). An elemental composition of the samples was studied by Energy Dispersive Spectroscopy(EDS). The observed results can be explained on the basis of composition and crystal size.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Structural and Dielectric Studies of Cerium Substituted Nickel Ferrite Nano P...theijes
Cerium substituted Nickel ferrite nanoparticles with general formula NiCeXFe2-XO4 (x=0.0, 0.05, 0.1, 0.15) have been synthesized by using sol-gel method. The crystalline structure and grain size of these particles were analyzed by using XRD; the particle size ranged from 12.22nm to 17.60nm.The decrease in value of the lattice parameter with doping suggests that there is shrinkage in unit cell. The single-phase cubic spinal structure was clearly indicated by the XRD patterns of pure NiFe2O4.The XRD pattern also show that all the samples had formed the cubic single phase spinal structure. Dielectric properties have been studied in the frequency range of 1 kHz to 5 MHz. Permittivity and tangent loss (tanδ) decreases with the substitution of Ce3+ in parent crystal structure.
Synthesis and characterization of pure zinc oxide nanoparticles and nickel do...eSAT Journals
Abstract In this paper, Zinc oxide nanoparticles are synthesized by simple wet chemical precipitation method. Zinc nitrate and sodium hydroxide are used as the starting materials.Zinc oxide nanoparticles are formed at a very low temperature of the order of 800C. Nickel doped zinc oxide nanoparticles are synthesized in two steps. In first step precipitate is obtained by reduction of mixture of zinc nitrate, ferric nitrate and starch by sodium hydroxide solution while in second step the given precipitate is thermally decomposed at high temperature of the order of 4000C. The crystallinity of the synthesized nanoparticles is then confirmed by X ray diffraction spectroscopy (XRD).The elemental composition of the powder is detected by Energy Dispersive X ray spectroscopy (EDAX). The morphology of the powder is investigated by Scanning Electron Microscopy (SEM). Magnetic characterization of nickel doped zinc oxide nanoparticles is done by Squid Magnetometer. Low temperature magnetization behavior revealed ferromagnetic behavior of sample. Key Words: Zinc oxide nanoparticles, Nickel doped ZnO, Antibacterial activity, Squid magnetometer, SEM
Synthesis and Structural Characterization of Cu Substituted Ni-Zn Nano-Ferrit...IJERA Editor
The ferrite nano particles having chemical formula Ni0.2CuxZn0.8-xFe2O4 (where x=0.0 to 0.8 with step of 0.2) were synthesized by Citrate-Gel Auto Combustion method at low temperature. The synthesized powders were sintered at 500oC for 4 hours in air and characterised by XRD, SEM with EDS. XRD analysis of prepared samples were confirmed the single phase cubic spinel Structure. The crystallite size (D) of prepared ferrites were in the range of 24-73nm. The values of lattice parameter (a) decreased and X-ray density (dx) were increased with the increasing of Cu substitution. The surface morphology of the prepared samples was investigated by Scanning Electron Microscope(SEM). An elemental composition of the samples was studied by Energy Dispersive Spectroscopy(EDS). The observed results can be explained on the basis of composition and crystal size.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Crystal Growth and Studies of Dihydrogen Phosphates of Potassium and Ammonium...IJERA Editor
A nonlinear optical (NLO) material Potassium dihydrogen phosphates (KDP) and Ammonium dihydrogen
phosphates (ADP) are grown by slow evaporation solution growth technique. The FTIR studies confirm the
presence of the functional group in the grown crystal. The optical transmittance studies show that the crystal has
transparence in the entire visible and IR region. The thermal stability of the materials was assessed by TG/DTA
analysis. The mechanical stability of the grown crystals was analyzed by Vicker’s microhardness test. The
dielectric behavior of the crystals was tested by dielectric analysis. The second harmonic generation (SHG) of
KDP is confirmed by Kurtz and Perry powder technique using Nd: YAG laser.
Crystal Growth and Studies of Dihydrogen Phosphates of Potassium and Ammonium...IJERA Editor
A nonlinear optical (NLO) material Potassium dihydrogen phosphates (KDP) and Ammonium dihydrogen
phosphates (ADP) are grown by slow evaporation solution growth technique. The FTIR studies confirm the
presence of the functional group in the grown crystal. The optical transmittance studies show that the crystal has
transparence in the entire visible and IR region. The thermal stability of the materials was assessed by TG/DTA
analysis. The mechanical stability of the grown crystals was analyzed by Vicker’s microhardness test. The
dielectric behavior of the crystals was tested by dielectric analysis. The second harmonic generation (SHG) of
KDP is confirmed by Kurtz and Perry powder technique using Nd: YAG laser.
IMPROVEMENT IN MORPHOLOGICAL AND ELECTRO-MAGNETIC BEHAVIOUR OF HARD FERRITE P...Editor IJMTER
The Ni-Ir substituted strontium ferrite of Sr(Ni-Ir)xFe12-2xO19 (x = 0.02 & 0.08) were
synthesized by sol-gel auto combustion technique and characterized using X-ray diffraction (XRD),
Transmission Electron Microscopy (TEM) for morphological behaviour with electrical
characteristics using Impedance Analyzer. XRD results confirmed the formation of a single phase
M-type hexagonal unit cell of space group P63/mmc. The increase in Ni-Ir concentration increases
the lattice parameter. TEM analysis of the sample demonstrates the formation of nano-size particles
which decreases with substitution. In this paper we reported the variation of dielectric constant,
dielectric loss, tangent loss, conductivity and magnetic behaviour with composition with temperature
and frequency analysis of the sample. The migration of Fe3+ ion from octahedral to tetrahedral site
decreases the dielectric constant with increase in Ni-Ir concentration. Activation energies were
found similar with calculated at ferromagnetic and paramagnetic region. The material study we
confined that the activation energy in the paramagnetic region is higher than that in the
ferromagnetic region. The enhanced resistivity of Ni-Ir substituted strontium hexaferrites is a
prospective application in high frequency and in microwave devices development.
- Nanoparticles NiFe2-xTbxO4 (x=0.00, 0.04, 0.08,
0.12) ferrite was prepared by solgel combution method. The
samples were characterized with X-ray diffraction and TEM
measurements. The effect of Tb3+ cations substitution on
structure of prepared nanoparticles was investigated. From the
analysis, the system was found to be inverse spinel cubic
structure. The lattice parameter (a) changes increases with Tb
doping content. Room temperature DC electrical resistivity
decreases. Dielectric properties have been studied in the
frequency range of 1 kHz to 5 MHz. Permittivity and tangent
loss (tanδ) decreases with the substitution of Tb3+ in parent
crystal structure.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Cation distribution of Ni2+ and Mg2+ ions improve structure and Magnetic Prop...AI Publications
In the present work, ferromagnetic Ni is slightly substituted for diamagnetic Mg spinal ferrites. The effect of Ni doping on the structural and magnetic properties of ferrites material in the form of NixMg1-xFe2O4 (x = 0.1,0.15,0.2,0.25, .0.3,0.35) has been the study. The Sol-gel auto Combustion method used to combine these substances uses urea as fuel. Sintered samples were shown using X-ray diffraction, Fourier Transform Infrared spectroscopy (FTIR) and a vibrating magnetometer sample. X-ray diffraction revealed that all the composite samples were pure cubic spinel arrays with a Fd3m space band and a permanent lattice that varied with Ni concentrations. the distribution of Ni2 + ions and Mg2+ ions in spinel ferrites indicates various changes in parameters such as tetrahedral ionic radius (rA), octahedral ionic radius (rB), hopping length (LA and LB). Fourier Transform Infrared (FT-IR) simulations showed wire vibration at the tetrahedral site and Octahedral site. spinel ferrites M-H curves are recorded at room temperature indicating normal hysteresis loop indicating the magnetic field.
Preparation, Structure, and Characterization of Nd2mo2o9 fast Oxide Ion Condu...IJARIIT
The structure and ion conductivity of Nd2Mo2O9powders were synthesized by using Nd(NO2)3, MoO3, and aspartic acid (fuel) in assisted combustion method with heating at 550˚C for 6 hours. The thermal decomposition, phase identification, morphology, ionic conductivity of the samples were studied by TGA/DTA, XRD and SEM four probe D.C. method respectively. The formation of Nd2Mo2O9 was confirmed by FTIR studies. The synthesis and crystallization were followed by thermochemical techniques (TGA/DTA) studies. The synthesized materials showed reasonable ionic conductivity. These results indicate that assisted combustion method is a promising method to prepare nanocrystalline Nd2Mo2O9 for solid oxide fuel cell.
Development of Ni-doped Yttria stabilized Zirconia composite for SOFC applica...IOSRJAP
Ni-doped Yttria stabilized Zirconia (NiO/YSZ) has been synthesized using low cost combustion process from an aqueous solution containing ZrO(NO3)2.6H2O, Y(NO3)3.6H2O, Ni(NO3)2.6H2O and urea. Pellets were sintered at 13500C for 5 hours and its sintered density is estimated to be of 95%. Sintered pellets were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) & X-ray photoelectron spectroscopy (XPS) techniques. From the XRD analysis, as grown powder of NiO/YSZ showed nano-crystalline behavior with homogeneous mixture of YSZ and NiO phases. However sintered powder showed µ-size dense grain growth. Temperature and frequency dependent dielectric properties are corroborated with the conduction mechanism. Both dielectric constant (K) and loss (tan δ) are increased sharply at high temperature region, which is expected to be the onset of dipolar relaxation phenomena due to the presence of oxygen vacancies. A mixed conductivity involving ionic conduction in the high temperature range and electronic conduction in the low temperature range was observed. The decrease in K and tan δ with increase in frequency at a given temperature suggests the dynamic interaction of oxygen vacancies & oxide ion pairs.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Crystal Growth and Studies of Dihydrogen Phosphates of Potassium and Ammonium...IJERA Editor
A nonlinear optical (NLO) material Potassium dihydrogen phosphates (KDP) and Ammonium dihydrogen
phosphates (ADP) are grown by slow evaporation solution growth technique. The FTIR studies confirm the
presence of the functional group in the grown crystal. The optical transmittance studies show that the crystal has
transparence in the entire visible and IR region. The thermal stability of the materials was assessed by TG/DTA
analysis. The mechanical stability of the grown crystals was analyzed by Vicker’s microhardness test. The
dielectric behavior of the crystals was tested by dielectric analysis. The second harmonic generation (SHG) of
KDP is confirmed by Kurtz and Perry powder technique using Nd: YAG laser.
Crystal Growth and Studies of Dihydrogen Phosphates of Potassium and Ammonium...IJERA Editor
A nonlinear optical (NLO) material Potassium dihydrogen phosphates (KDP) and Ammonium dihydrogen
phosphates (ADP) are grown by slow evaporation solution growth technique. The FTIR studies confirm the
presence of the functional group in the grown crystal. The optical transmittance studies show that the crystal has
transparence in the entire visible and IR region. The thermal stability of the materials was assessed by TG/DTA
analysis. The mechanical stability of the grown crystals was analyzed by Vicker’s microhardness test. The
dielectric behavior of the crystals was tested by dielectric analysis. The second harmonic generation (SHG) of
KDP is confirmed by Kurtz and Perry powder technique using Nd: YAG laser.
IMPROVEMENT IN MORPHOLOGICAL AND ELECTRO-MAGNETIC BEHAVIOUR OF HARD FERRITE P...Editor IJMTER
The Ni-Ir substituted strontium ferrite of Sr(Ni-Ir)xFe12-2xO19 (x = 0.02 & 0.08) were
synthesized by sol-gel auto combustion technique and characterized using X-ray diffraction (XRD),
Transmission Electron Microscopy (TEM) for morphological behaviour with electrical
characteristics using Impedance Analyzer. XRD results confirmed the formation of a single phase
M-type hexagonal unit cell of space group P63/mmc. The increase in Ni-Ir concentration increases
the lattice parameter. TEM analysis of the sample demonstrates the formation of nano-size particles
which decreases with substitution. In this paper we reported the variation of dielectric constant,
dielectric loss, tangent loss, conductivity and magnetic behaviour with composition with temperature
and frequency analysis of the sample. The migration of Fe3+ ion from octahedral to tetrahedral site
decreases the dielectric constant with increase in Ni-Ir concentration. Activation energies were
found similar with calculated at ferromagnetic and paramagnetic region. The material study we
confined that the activation energy in the paramagnetic region is higher than that in the
ferromagnetic region. The enhanced resistivity of Ni-Ir substituted strontium hexaferrites is a
prospective application in high frequency and in microwave devices development.
- Nanoparticles NiFe2-xTbxO4 (x=0.00, 0.04, 0.08,
0.12) ferrite was prepared by solgel combution method. The
samples were characterized with X-ray diffraction and TEM
measurements. The effect of Tb3+ cations substitution on
structure of prepared nanoparticles was investigated. From the
analysis, the system was found to be inverse spinel cubic
structure. The lattice parameter (a) changes increases with Tb
doping content. Room temperature DC electrical resistivity
decreases. Dielectric properties have been studied in the
frequency range of 1 kHz to 5 MHz. Permittivity and tangent
loss (tanδ) decreases with the substitution of Tb3+ in parent
crystal structure.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Cation distribution of Ni2+ and Mg2+ ions improve structure and Magnetic Prop...AI Publications
In the present work, ferromagnetic Ni is slightly substituted for diamagnetic Mg spinal ferrites. The effect of Ni doping on the structural and magnetic properties of ferrites material in the form of NixMg1-xFe2O4 (x = 0.1,0.15,0.2,0.25, .0.3,0.35) has been the study. The Sol-gel auto Combustion method used to combine these substances uses urea as fuel. Sintered samples were shown using X-ray diffraction, Fourier Transform Infrared spectroscopy (FTIR) and a vibrating magnetometer sample. X-ray diffraction revealed that all the composite samples were pure cubic spinel arrays with a Fd3m space band and a permanent lattice that varied with Ni concentrations. the distribution of Ni2 + ions and Mg2+ ions in spinel ferrites indicates various changes in parameters such as tetrahedral ionic radius (rA), octahedral ionic radius (rB), hopping length (LA and LB). Fourier Transform Infrared (FT-IR) simulations showed wire vibration at the tetrahedral site and Octahedral site. spinel ferrites M-H curves are recorded at room temperature indicating normal hysteresis loop indicating the magnetic field.
Preparation, Structure, and Characterization of Nd2mo2o9 fast Oxide Ion Condu...IJARIIT
The structure and ion conductivity of Nd2Mo2O9powders were synthesized by using Nd(NO2)3, MoO3, and aspartic acid (fuel) in assisted combustion method with heating at 550˚C for 6 hours. The thermal decomposition, phase identification, morphology, ionic conductivity of the samples were studied by TGA/DTA, XRD and SEM four probe D.C. method respectively. The formation of Nd2Mo2O9 was confirmed by FTIR studies. The synthesis and crystallization were followed by thermochemical techniques (TGA/DTA) studies. The synthesized materials showed reasonable ionic conductivity. These results indicate that assisted combustion method is a promising method to prepare nanocrystalline Nd2Mo2O9 for solid oxide fuel cell.
Development of Ni-doped Yttria stabilized Zirconia composite for SOFC applica...IOSRJAP
Ni-doped Yttria stabilized Zirconia (NiO/YSZ) has been synthesized using low cost combustion process from an aqueous solution containing ZrO(NO3)2.6H2O, Y(NO3)3.6H2O, Ni(NO3)2.6H2O and urea. Pellets were sintered at 13500C for 5 hours and its sintered density is estimated to be of 95%. Sintered pellets were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) & X-ray photoelectron spectroscopy (XPS) techniques. From the XRD analysis, as grown powder of NiO/YSZ showed nano-crystalline behavior with homogeneous mixture of YSZ and NiO phases. However sintered powder showed µ-size dense grain growth. Temperature and frequency dependent dielectric properties are corroborated with the conduction mechanism. Both dielectric constant (K) and loss (tan δ) are increased sharply at high temperature region, which is expected to be the onset of dipolar relaxation phenomena due to the presence of oxygen vacancies. A mixed conductivity involving ionic conduction in the high temperature range and electronic conduction in the low temperature range was observed. The decrease in K and tan δ with increase in frequency at a given temperature suggests the dynamic interaction of oxygen vacancies & oxide ion pairs.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
2. 124 | International Conference on “Applied Nanotechnology and Nanoscience”(ICANN 2017)
ISSN 2322-0015 http://www.irjse.in
intelligent design of functional materials, components
and systems with attractive qualities and functions
[3-4]. Magnetic nanomaterials intensively studied as a
recording media due to their superior physical
properties. These properties make ferrites an ideal
candidate for technical applications such as magnetic
resonance imaging enhancement, catalysis, sensors
and pigments [5]. Combined spinel ferrites have been
studied intensively over the last few years due to
their potential applications. Spinel ferrites have the
chemical formula MFe2O4 in which M can be any
divalent metal cations. In spinel ferrite, oxygen forms
face centre cubic (FCC) lattice with divalent cations at
tetrahedral (A) and/or octahedral (B) sites.
Magnesium ferrite (MgFe2O4) has an inverse spinel
structure with the preference of Mg2+ cations mainly
on octahedral sites [6-9], while Zinc ferrite (ZnFe2O4)
has normal spinel structure, in which Zn2+ cations
mainly occupy tetrahedral sites [6-10]. The small scale
size of the well-known spinel ferrites has opened up
the door for intensive research to utilize their
properties for biomedical applications [11-13].
Numerous methods were reported in literature
showing the possibilities of producing particle size in
the range of 2 - 100 nm [14-15]. In this work, Ni1-x Cdx
Yy Fe2-y O4 (where x = 0, 0.2, 0.4, 0.6 and y = 0, 0.075)
were synthesized using co-precipitation methods. X-
ray diffraction was used to investigate the structural
and Ultraviolet visible spectrometer and Fourier
Transform Infrared Spectroscopy were used to
investigate the optical properties of crystallite
nanoparticles.
METHODOLOGY
The Y3+ doped in Ni-Cd ferrite powders were
synthesized by sol-gel autocombustion method at
low temperatures for different compositions of Ni1-x
Cdx Yy Fe2-y O4 (where x = 0, 0.2, 0.4, 0.6 and y = 0,
0.075). The AR grade nitrate of Merck company
(purity of 99%) are used in the experiments such as
Yttrium nitrate (Y(NO3).6H2O), Nickel nitrate
(Ni(NO3)·6H2O), Cadmium nitrate (Cd(NO3)·6H2O),
Ferric nitrate (Fe(NO3)3.9H2O). These nitrates and
citric acid are using stoichiometric ratio proportion to
obtain the final product and the citric acid (C6H8O7) is
used as a fuel in the ratio 1:3. The proportion of each
reagent was defined according to its respective molar
amounts [16]. All chemicals are dissolved in distilled
water and were stirred till to obtain the homogeneous
solution. To maintain pH equal to 7 by adding drop
by drop ammonium hydroxide (NH4OH) during the
stirring process. This solution was stirred continuo-
usly with 80
C for about 4-5 hours to obtain sol. After
4-5 hours, gel converts into ash and ash convert into
powder. Finally get fine powder of Ni1-x Cdx Yy Fe2-y
O4 ferrite nanoparticles after auto combustion. The
powder was sintered at 400
C for 2 hours.
The structural characterization was done using XRD
analysis. The X-ray diffractometer with Cu-Kα
radiation of wavelength 1.5405 A0 at 40 kV performed
a scanning from 20 to 80 degree at a step size of 0.02
degree per second for each prepared sample and
determined crystal structure, lattice parameter and
crystallite size. The optical characteristics was studied
using Fourier Transformation Infrared spectroscopy
(FTIR) of Bruker 3000 Hyperion microscope with
vertex 80 single point detector performing images
resolution ranging between 7500 to 450 cm-1 and UV-
Visible spectroscopy. Further investigations of the
optical properties are under way to elucidate the
effective role of inter particle interactions in these
samples.
RESULTS AND DISCUSSION
3.1 Structural Studies:
XRD analysis: The resulting powder Ni1-x Cdx Yy Fe2-y
O4 (where x = 0, 0.2, 0.4, 0.6 and y = 0, 0.075)
nanocrystals were characterized by XRD pattern. The
XRD pattern of sintered Y3+ doped the nickel-
magnesium-cadmium ferrite nano crystals as shown
in figure-2. Obtained XRD pattern and crystalline
phases were identified and it conformed the formation
of a homogeneous well-defined spinal cubic structure
with put any impurity. The broad peaks in the XRD
pattern indicate a fine particle nature of the particles.
The particle size was determined using Scherer’s
formula.
The average particle sizes of nanoparticles are given
in Table-1. The particle size decreases as the
3. Bhise and Rathod, 2017 125
Int. Res. J. of Science & Engineering, Special Issue A1, December, 2017
concentration of Y3+ increases. Lattice parameter
obtained for prepared sample is ranging between
8.3399 to 8.3665 A0 and average grain size ranging
between 12.5 to 34.8 nm. The deviation in lattice
parameter can be attributed to the cations
rearrangement in the nano sized prepared ferrites.
Value of lattice constant for Ni-Cd doped Yttrium
ferrite shows the expansion of unit cell with rare
earth doping when compared with pure Yttrium
ferrite. This is expected due to substitution of large
ionic radius of Y3+ ions (0.9 A0) with small ionic
radius Fe3+ ions (0.645 A0). This result in Y3+
substituted ferrites to have higher thermal stability
relative to Ni-Cd ferrite.
Table-1: The particle size of Ni1-x Cdx Yy Fe2-y O4 by
XRD
Table-2: The band gap energy of Ni1-x Cdx Yy Fe2-y O4
byUV- Visible spectroscopy
Composition
Average
grain size
(t) nm
Lattice
constant (a)
Ao
Composition Wavelength
(nm)
Band gap energy
(eV)
Tangent
Method
Tauc
Method
Ni Fe2 O4 34.77 8.3399 x=0.2, y=0 751.25 1.6505 1.6382
Ni0.8 Cd0.2 Fe2 O4 25.15 8.3455 x=0.2, y=0.075 762.1 1.6270 1.6603
Ni0.8 Cd0.2 Y0.075 Fe1.925 O4 20.76 8.3591 x=0.4, y=0.075 770.9 1.6085 1.6789
Ni0.6 Cd0.4 Y0.075 Fe1.925 O4 16.05 8.3635 x=0.6, y=0.075 760 1.6315 1.6774
Ni0.4 Cd0.6 Y0.075 Fe1.925 O4 12.49 8.3665 Average Value 1.6294 1.6637
Figure 2: XRD pattern of Ni1-x Cdx Yy Fe2-y O4 Figure 3: Variation of Band gap energy of Ni1-x Cdx Yy
Fe2-y O4 ferrite system with yttrium content(y)
Figure 4: UV-Visible spectra of Ni1-x Cdx Yy Fe2-y O4
nanoferites
Figure 5: Band gap energy of Ni1-x Cdx Yy Fe2-y O4
nanoferrites using Tauc method
4. 126 | International Conference on “Applied Nanotechnology and Nanoscience”(ICANN 2017)
ISSN 2322-0015 http://www.irjse.in
3.2 Optical Studies:
a) UV Visible Analysis:
The figure-3 shows optical properties were studied
from UV-Visible spectroscopy to calculate the band
gap energy. In the absorption molecules of non-
bonding electrons can absorb the energy in the form of
ultraviolet or visible light to excite this electron to
higher or anti-bonding molecular orbit. The energy
band gap was calculated for samples. Energy band
gap was found to be 1.6505, 1.6270, 1.6085 and 1.6315
eV. The substitution was resulted in slight increase in
the lattice constant and that sequentially may lead to
the slightly decrease in the energy gap. The average
Band gap of prepared sample is 1.6294 eV and
wavelength absorb by 761.06 nm. It is in the range of
semiconductor materials.
The energy band gap was also determined by Tauc
method for samples. It is 1.6505, 1.6270, 1.6085 and
1.6315 eV. The substitution was resulted in slightly
decrease in the energy gap and the average Band gap
is 1.6294 eV. It is also in the range of semiconductor
materials.
b) FTIR Analysis: In order to investigate the
chemical functional groups on the synthesized Ni1-x
Cdx Yy Fe2-y O4, FTIR spectroscopy are performed. The
FTIR spectra of the prepared Ni0.6 Cd0.4 Y0.075 Fe1.925 O4
are shown in figure 6 to know the bonding
characteristics of the materials. The peaks at 476.71
cm-1 and 559.97 cm-1 are the peaks of Fe-O bond in Y
doped Ni-Cd ferrite and it is arises due to the lattice
vibrations of the oxide ions against cations. The peak
at 1383.62 cm-1 indicates the presence of O-H bond
due to bending vibration. The broad peak at 3431.91
cm-1 gives presence of hydroxyl group in the material
and indicates that the material absorbed moisture
from atmosphere during analysis.
The intense absorption bond is observed at 559.97 cm-1
which shows the characteristic bond of spinel
structure which may due to presence of Fe-O and Y-O
bonds or crystalline nature of Y doped Ni-Cd ferrite.
Hence, FTIR analysis supports the observation of XRD
analysis and confirms the crystalline nature of ferrite.
So, the peaks at 476.71 cm-1 and 1032.57 cm-1 confirms
the presence of yttrium doped in Ni-Cd ferrite.
Finally, the doping of Y3+ on Ni-Cd ferrite was
confirmed by different pattern of the plots and the
difference in relative position and intensity of the
peaks appeared in the FTIR plots of the prepared
samples.
Figure 6: IR spectrum of Ni0.6 Cd0.4 Y0.075 Fe1.925 O4 nanoferrites Figure 7: Absorption spectra of Ni0.6 Cd0.4 Y0.075
Fe1.925 O4 ferrites