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Nano Copper Ferrite Catalyzed Sonochemical, One-Pot Three and Four Component Synthesis of Poly Substituted Imidazoles  [PDF]
Paul D. Sanasi, Ravi K. Majji, Swathi Bandaru, Satyanarayana Bassa, Surekha Pinninti, Sruthi Vasamsetty, Raghu B. Korupolu
Modern Research in Catalysis (MRC) , 2016, DOI: 10.4236/mrc.2016.51004
Abstract: A simple, multi component, one-pot method has been reported for the synthesis of poly substituted imidazoles in presence of magnetically separable and recyclable spinel nano copper ferrite as heterogeneous catalyst by the cyclo-condensation of benzil, aromatic aldehyde, ammonium acetate and substituted amines under ultrasonic irradiation. This method of preparation has many advantages compared to those methods which are previously reported in the literature. This methodology offers simple experimental procedure, milder reaction conditions and environmentally benign approach.
Synthesis of N-substituted Acridinediones and Polyhydroquinoline Derivatives in Refluxing Water  [PDF]
Jing-Jing Xia,Ke-Hua Zhang
Molecules , 2012, DOI: 10.3390/molecules17055339
Abstract: Acridinediones were synthesized by the one-pot Hantzsch condensation of an aromatic aldehyde, 5,5-dimethyl-1,3-cyclohexanedione, and aniline/4-methylaniline in re?uxing water. This method has then been extended to the four-component reaction of an aromatic aldehyde, 5,5-dimethyl-1,3-cyclohexanedione, ethyl acetoacetate and ammonium acetate for the synthesis of polyhydroquinoline derivatives. This is an environmentally friendly and efficient procedure providing?good to excellent yields.
Sonochemical Synthesis of Cobalt Ferrite Nanoparticles  [PDF]
Partha P. Goswami,Hanif A. Choudhury,Sankar Chakma,Vijayanand S. Moholkar
International Journal of Chemical Engineering , 2013, DOI: 10.1155/2013/934234
Abstract: Cobalt ferrite being a hard magnetic material with high coercivity and moderate magnetization has found wide-spread applications. In this paper, we have reported the sonochemical synthesis of cobalt ferrite nanoparticles using metal acetate precursors. The ferrite synthesis occurs in three steps (hydrolysis of acetates, oxidation of hydroxides, and in situ microcalcination of metal oxides) that are facilitated by physical and chemical effects of cavitation bubbles. The physical and magnetic properties of the ferrite nano-particles thus synthesized have been found to be comparable with those reported in the literature using other synthesis techniques. 1. Introduction The spinel ferrite nanoparticles have exceptional electronic and magnetic properties, which are quite different from the bulk materials [1]. As a result, the magnetic ferrite nanoparticles have found wide applications in information storage systems, ferrofluids, and medical applications like magnetic drug delivery and hyperthermia for cancer treatment [2]. Among metal ferrites, zinc, nickel, and cobalt ferrites have been mostly applied. Cobalt ferrite (CoFe2O4) is a hard magnetic material that is known to have high coercivity and moderate magnetization [3]. On nanoscale, the cobalt ferrite achieves properties of high saturation magnetization, high coercivity, strong anisotropy, high mechanical hardness, and high chemical stability [4]. Conventional techniques for synthesis of metal nanoparticles (including cobalt ferrite particles) are sol-gel method [5, 6], microemulsions [7, 8], reverse micelles [9], autocombustion, [10] and coprecipitation [11]. A relatively new technique for synthesis of ferrite nanoparticles is the sonochemical route [12–16], in which the reaction mixture is exposed to ultrasound irradiation. Spectacular physical and chemical effects induced by ultrasound bring about the synthesis of metal ferrites from the metal salt precursors, usually acetates. The hydrolysis of acetates, followed by oxidation of the hydroxides to oxides and the reaction between oxides to yield ferrites is brought about by ultrasound and its secondary effect, cavitation. Cavitation is essentially nucleation, growth and transient implosive collapse of gas bubbles driven by ultrasound wave [17]. This technique has been well demonstrated for zinc ferrites. In our previous papers [15, 16], we have tried to illuminate the links between physics of ultrasound and cavitation and the chemistry of zinc ferrite nanoparticles. It was revealed in these studies that chemical species produced during transient
International Journal of Engineering Science and Technology , 2011,
Abstract: Cobalt ferrite (CoFe2O4) is a spinel ferrimagnetic oxide with high saturation magnetization, large magnetocrystalline anisotropy. Highly crystalline cobalt ferrite particles have been prepared using a newsynthesis method i.e. microwave route. This microwave assisted route is one of the simplest and easy methods for synthesis. Here, cobalt ferrite (CoFe2O4) is prepared by microwave route using thermal decomposition of cobalt oxalate precursor. Urea is used as a fuel for the solid-state combustion reaction. In this article, we reportthe investigation of ac conductivity and dielectric behavior of cobalt ferrite in the frequency range of 1 KHz to 1MHz and in the temperature range of 00 to 7000 C. The obtained ac conductivity is found to be very low. The experimental results indicate an abnormal behavior in case of dielectric properties.
Magnetic Properties of the Cobalt Ferrous Spinel Ferrite Nanoparticles Formed on the Steel Surface Contacting with Cobalt Chloride Water Solutions in Open-air System  [cached]
Lavrynenko O.M.,Dudchenko N.,Brik A.B.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: The paper describes creation of cobalt ferrous spinel ferrite nanoparticles and investigation of their phase composition, surface structure and magnetic properties. Cobalt ferrous spinel ferrite nanoparticles were synthesized in an aerated system of steel electrode contacting with aqueous cobalt chloride at differ-ent pH values of solution. According to X-Ray diffraction data, it was shown, that some impurity phases also formed during the synthesis process, notably, lepidocrocite and goethite on the steel surface and Green Rust I, cobalt hydroxide, heterohenite in the solution. The quantity of such phases depends on pH value of initial solution. The size of synthesized cobalt ferrous spinel ferrite nanoparticles was approximately 10-12 nm. Saturation magnetization of synthesized cobalt ferrous spinel ferrite nanoparticles is rather high. Syn-thesized magnetic cobalt ferrous spinel ferrite nanoparticles are promising for different medical-biological applications.
Structural and Electrical Properties of Cobalt Ferrite

材料科学技术学报 , 1996,
Abstract: Ferrites are a class of cohesive new materiafs required for many specialised applications. Cobalt ferrite (CoFe2O4) has been identified as a substitute for carbon and serves as a non consumable anode for an eco-friendly and energy efficient production of aluminium. Pellets of cobalt ferrite have been prepared by powder metallurgical process and their electrical properties have been investigated from ambient temperature to 1273 K. The structural and morphological features have been studied by X-ray diffraction and scanning electron microscopy The relationships between such properties, chemical composition and sintering temperatures are thoroughly discussed.
Ferrite cavities  [PDF]
H. Klingbeil
Physics , 2012,
Abstract: Ferrite cavities are used in synchrotrons and storage rings if the maximum RF frequency is in the order of a few MHz. We present a simple model for describing ferrite cavities. The most important parameters are defined, and the material properties are discussed. Several practical aspects are summarized, and the GSI SIS18 ferrite cavity is presented as an example.
Structural and Electrical Properties of Cobalt Ferrite Nanoparticles  [PDF]
Dr.A.B. Shinde
International Journal of Innovative Technology and Exploring Engineering , 2013,
Abstract: Cobalt ferrite nano-powders were obtained by sol-gelauto-combustion method using citric acid as a fuel. The metalnitrate to citric acid ratio was taken as 1:3. The as preparedpowder of cobalt ferrite nanoparticles is annealed at 5500C for 4hrs and the same powder was used for characterization andinvestigations of structural and electrical properties.Thestructural characterization of cobalt ferrite nanoparticles weredone by X-ray diffraction technique. Micro-structural andmorphological studies were carried out by scanning electronmicroscope technique and energy dispersive spectrum. Theaverage crystallite size obtained by Scherrer’s formula is of theorder of 34 nm. The grain size and specific surface area of thecobalt ferrite nanoparticles is 34 nm and 55 respectively. Thelattice constant determined from XRD data is in the reportedrange (8.3783 A.U.). The porosity estimated from X- ray densityand bulk density shows large value of the order of 47 %. The D.Celectrical resistivity was investigated from room temperature to850 K using two probe technique. The variation of dc electricalresistivity with temperature is explained in this work.
An environmentally benign one-pot synthesis of 1,2-dihydro-1-aryl-3H-naphth[1,2-e][1,3]oxazin-3-one derivatives catalysed by phosphomolybdic acid  [PDF]
Journal of the Serbian Chemical Society , 2011,
Abstract: A phosphomolybdic acid catalysed novel method for the synthesis of 1,2-dihydro-1-aryl-3H-naphth[1,2-e][1,3]oxazin-3-one derivatives by a one-pot, three-component reaction of β-naphthol, aromatic aldehydes and urea in excellent yields is described.
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: It has been observed that for cobalt ferrite the coefficient of magnetostriction is maximum but the observed value of magnetoelectric coefficient is low as compared to the value calculated on the basis of known piezo-electric coefficient(d) and magnetostrictive strain( ). It was predicted that a large value of magneto crystalline anisotropy of cobalt ferrite reduces the effective magneto electric coupling. To improve the magneto electric coupling still maintaining the values of resistivity (p), Saturation magnetization (Ms) and initial permeability (ì) high, substitution of Nickel is found to be useful. Further substitution of Mn at Aor B-site is reported to improve , and reduce anisotropy energy k1, coeresive field (Hc) and curie temperature (Tc) of the material. Therefore it was interesting to determine Magnetic properties of submicron level Ni and Mn substituted Cobalt Ferrite.
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