Structure and Properties of Magnetic Ceramic Nanoparticles

2014 ◽  
Vol 1655 ◽  
Author(s):  
Monica Sorescu ◽  
Tianhong Xu ◽  
Lucian Diamandescu
Keyword(s):  
Mechanochemical Activation ◽  
Basic Research ◽  
Point Of View ◽  
Structure And Properties ◽  
Scientific Interest ◽  
X Ray Diffraction ◽  
Recoilless Fraction ◽  
X Ray ◽  
Ceramic Nanoparticles

ABSTRACTMost recently, magnetic ceramic nanoparticles have attracted considerable scientific interest from the basic research point of view and for their prospective use in chemical sensing, catalysis and electrochemical applications. In this paper we report the successful synthesis of xSnO2-(1-x)α-Fe2O3 system by hydrothermal synthesis and that of xZrO2-(1-x)α-Fe2O3 system by mechanochemical activation. The two nanoparticle systems were analyzed side-by-side using X-ray diffraction (XRD) and Mössbauer spectroscopy. The latter technique was used in its complexity, including the determination of the recoilless fraction using our dual absorber method. This was correlated with the onset of new phases in the systems of interest.

Mechanochemical Synthesis of Novel Sensor Materials

2009 ◽  
Vol 1226 ◽  
Author(s):  
Monica Sorescu ◽  
Lucian Diamandescu ◽  
Adelina Tomescu
Keyword(s):  
Ball Milling ◽  
Milling Time ◽  
Gas Sensing ◽  
Mechanochemical Activation ◽  
Magnetic Characteristics ◽  
X Ray Diffraction ◽  
Recoilless Fraction ◽  
X Ray ◽  
Immiscible System ◽  
Sensing Applications

AbstractThe xZnO-(1-x)alpha-Fe2O3 and xZrO2-(1-x)alpha-Fe2O3 nanoparticles systems have been obtained by mechanochemical activation for x=0.1, 0.3 and 0.5 and for ball milling times ranging from 2 to 24 hours. Structural and magnetic characteristics of the zinc and zirconium-doped hematite systems were investigated by X-ray diffraction (XRD), Mössbauer spectroscopy and conductivity measurements. Using the dual absorber method, the recoilless fraction was derived as function of ball milling time for each value of the molar concentration involved. As ZnO is not soluble in hematite in the bulk form, the present study clearly illustrates that the solubility limits of an immiscible system can be extended beyond the limits in the solid state by mechanochemical activation. Moreover, this synthetic route allowed us to reach nanometric particle dimensions, which makes these materials very important for gas sensing applications.

The Crystal Structure of Rubber Hydrochloride

1943 ◽  
Vol 16 (4) ◽  
pp. 848-856
Author(s):  
C. W. Bunn ◽  
E. V. Garner
Keyword(s):  
Crystal Structure ◽  
Physical Properties ◽  
Carbon Chain ◽  
Point Of View ◽  
X Ray Diffraction ◽  
X Ray ◽  
Carbon Compounds ◽  
Ray Methods ◽  
Temperature Melting

Abstract “Rubber hydrochloride”, the crystalline substances made by addition of hydrogen chloride to rubber, is of interest for two reasons. First, the periodicity along the fibre axis of drawn specimens indicates that the carbon chain has not the simple plane zigzag form found in paraffin hydrocarbons, but is somewhat shortened by folding. There is similar evidence that several other chain polymers also have folded chains; the elucidation of the geometry of such molecules would form a useful contribution to our knowledge of the stereochemistry of carbon compounds in general and chain polymers in particular. Rubber hydrochloride appeared to be a suitable substance for crystallographic investigation from this point of view: it gives a well-defined x-ray diffraction pattern. Moreover, a prediction of the chain form has been made on the basis of a knowledge of the periodicity and the use of a hypothesis which has been called the principle of staggered bonds. The determination of the structure by x-ray methods forms the first test of the validity and usefulness of this hypothesis. Secondly, rubber hydrochloride is interesting on account of its physical properties. Unlike rubber itself, it is crystalline at room temperature, “melting” at about 115° C. The present work on its crystal structure forms part of a program of research being carried out in this laboratory, and is a contribution to the attempt to understand the physical properties of chain polymers in terms of molecular structure.

scholarly journals Influence of decyl glucoside on the electrodeposition of tin

2006 ◽  
Vol 71 (6) ◽  
pp. 661-668 ◽  
Author(s):  
Mohamed Charrouf ◽  
Said Bakkali ◽  
Mohammed Cherkaoui ◽  
Mahassin Amrani
Keyword(s):  
Surface Active Agent ◽  
Active Agent ◽  
Point Of View ◽  
X Ray Diffraction ◽  
X Ray ◽  
Deposition Kinetics ◽  
Structural Modifications ◽  
Surface Active ◽  
Acidic Sulphate

The aim of the present study was to improve an electrochemical deposition bath for tin coating an acidic sulphate medium by addition of decyl glucoside. The effects of this additve on the deposition kinetics were examined by electrochemical methods, namely voltammetry and galvanostatic tin-layer formation, while scanning electron microscopy and X-ray diffraction analysis allowed the determination of the morphological and structural modifications resulting from the addition of this new surface active agent. The presence of the examined additive induced an increase of the activation energy and of the overvoltage of the reduction of stannous ions. From the morphological point of view, a marked decrease in the grain size of the deposit was achieved in the presence of the additive. The preferential crystal growth axes was also changed from Sn (200) without additive to Sn (112) with the additive.

scholarly journals The HXD95: a modified Bassett-type hydrothermal diamond-anvil cell for in situ XRD experiments up to 5 GPa and 1300 K

2020 ◽  
Vol 27 (2) ◽  
pp. 529-537 ◽  
Author(s):  
Marion Louvel ◽  
James W. E. Drewitt ◽  
Allan Ross ◽  
Richard Thwaites ◽  
Benedict J. Heinen ◽  
...  
Keyword(s):  
Diamond Anvil Cell ◽  
Complex Compounds ◽  
Industrial Processes ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
In Situ Xrd ◽  
Diamond Anvil

A new diamond-anvil cell apparatus for in situ synchrotron X-ray diffraction measurements of liquids and glasses, at pressures from ambient to 5 GPa and temperatures from ambient to 1300 K, is reported. This portable setup enables in situ monitoring of the melting of complex compounds and the determination of the structure and properties of melts under moderately high pressure and high temperature conditions relevant to industrial processes and magmatic processes in the Earth's crust and shallow mantle. The device was constructed according to a modified Bassett-type hydrothermal diamond-anvil cell design with a large angular opening (θ = 95°). This paper reports the successful application of this device to record in situ synchrotron X-ray diffraction of liquid Ga and synthetic PbSiO3 glass to 1100 K and 3 GPa.

scholarly journals Synthesis and characterization of pyridine-3-carboxylic acid hexamolybdochromate (С6H5NO2)2[H3O]4[CrMo6O18(OH)6].4Н2О

2019 ◽  
Vol 59 (7) ◽  
pp. 50-55
Author(s):  
Garry Z. Kaziev ◽  
◽  
Anna F. Stepnova ◽  
Van Bang Nguyen ◽  
Viktor N. Khrustalev ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Nicotinic Acid ◽  
Point Of View ◽  
X Ray Diffraction ◽  
High Biological Activity ◽  
X Ray ◽  
Cell Parameters ◽  
Composition And Structure ◽  
Ir Spectroscopic

The Chemistry of heteropoly compounds (HPC) is one of the modern direction of Coordination chemistry. In current times, the high importance in the development of HPC chemistry is the synthesis of new hybrid, organic-inorganic heteropolystructures with preassigned physicochemical properties as well as the determination of common factors of change in these properties depending on the composition and structure. The X-ray diffraction study of the obtained compounds has showed that the packing of molecules into crystals is carried out with the formation of through channels along the c axis, which can play a significant role, for example, during catalytic processes. The ability of natural nicotinic acid to form complexes with heteropolyanion [CrMo6(ОН)6O18]4- is known. The high biological activity of nicotinic acid, as well as the activity of a number of polymetallates to the suppression of certain types of viruses which was described in the literature, make it possible to consider hybrid materials based on these substances promising from the point of view of the consciousness of new pharmaceuticals. Based on this data, we have synthesized pyridine-3-carboxylic acid hexamolybdochromate of composition (С6H5NO2)2[H3O]4[CrMo6O18(OH)6].4Н2О. The compound was studied by chemical, X-ray diffraction, thermogravimetric, NMR and IR spectroscopic methods of analysis. It is established that the synthesized compound crystallizes in triclinic syngony with unit cell parameters: а = 9.1640(8)Å, b = 10.6441(11)Å, с = 10.8241(12)Å; α = 95.968(10)°, β = 109.864(12)°, γ = 105.059(11)°; calc .= 2.502 g/cm3, V = 937.2(2) Å3; Z = 1.

Sem and X-Ray Analysis of Renal and Biliary Calculi

1976 ◽  
Vol 34 ◽  
pp. 306-307
Author(s):  
R. J. Narconis ◽  
G. L. Johnson
Keyword(s):  
Chemical Constituents ◽  
Natural State ◽  
X Ray Diffraction ◽  
Chemical Methods ◽  
X Ray ◽  
Additional Dimension ◽  
Biliary Calculi ◽  
Calculus Formation ◽  
Scanning Electron

Analysis of the constituents of renal and biliary calculi may be of help in the management of patients with calculous disease. Several methods of analysis are available for identifying these constituents. Most common are chemical methods, optical crystallography, x-ray diffraction, and infrared spectroscopy. The application of a SEM with x-ray analysis capabilities should be considered as an additional alternative.A scanning electron microscope equipped with an x-ray “mapping” attachment offers an additional dimension in its ability to locate elemental constituents geographically, and thus, provide a clue in determination of possible metabolic etiology in calculus formation. The ability of this method to give an undisturbed view of adjacent layers of elements in their natural state is of advantage in determining the sequence of formation of subsequent layers of chemical constituents.

New Coordination Compounds of Fe(III) with Organic Ligands

2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Mihaela Flondor ◽  
Ioan Rosca ◽  
Doina Sibiescu ◽  
Mihaela-Aurelia Vizitiu ◽  
Daniel-Mircea Sutiman ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Complex Compounds ◽  
Organic Ligands ◽  
X Ray Diffraction ◽  
X Ray ◽  
Elemental Chemical Analysis ◽  
Structural Formulae ◽  
Paramagnetic Properties

In this paper the synthesis and the study of some complex compounds of Fe(III) with ligands derived from: 2-(4-chloro-phenylsulfanyl)-1-(2-hydroxy-3,5-diiodo-phenyl)-ethanone (HL1), 1-(3,5-dibromo-2-hydroxy-phenyl)-2-phenylsulfanyl-ethanone(HL2), and 2-(4-chloro-phenylsulfanyl)-1-(3,5-dibromo-2-hydroxy-phenyl)-ethanone (HL3) is presented. The characterization of these complexes is based on method as: the elemental chemical analysis, IR and ESR spectroscopy, M�ssbauer, the thermogravimetric analysis and X-ray diffraction. Study of the IR and chemical analysis has evidenced that the precipitates form are a complexes and the combination ratio of M:L is 1:2. The central atoms of Fe(III) presented paramagnetic properties and a octaedric hybridization. Starting from this precipitation reactions, a method for the gravimetric determination of Fe(III) with this organic ligands has been possible. Based on the experimental data on literature indications, the structural formulae of the complex compounds are assigned.

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