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UV andorange-redlightemittingzincoxidenano-phosphors(ZnONPr)weresynthesisedbya combustion methodusingzincnitrateandzincacetateasprecursorsandureaasafuel.Hexagonal wurtzite structuresofZnOweresynthesised.X-rayphotoelectronspectroscopy(XPS)indicatedthatthe O1s peakconsistofthreecomponents:O1(ZnO),O2(deficient oxygen;OHgroups)andO3(adsorbed species) centredat530.3,531.2and532.6eV,respectively.Abroadorange-redemissionfrom500to 850 nmwasobtainedfromtheZnONPrpreparedwiththenitrateprecursorwhichmaybeattributedto different kindsofdefects,andasharpUVband,duetothepossiblepassivationofdefects,at392nmfrom ZnO NPrpreparedwithacetateprecursor. WethanktheSouthAfricanNationalResearchFoundationand UFS for financial support.AuthorsarealsothankfultoDr.Mukut Ghoain, DepartmentofChemistry,UFSforfruitfulscientific discussion. UV andorange-redlightemittingzincoxidenano-phosphors(ZnONPr)weresynthesisedbya combustion methodusingzincnitrateandzincacetateasprecursorsandureaasafuel.Hexagonal wurtzite structuresofZnOweresynthesised.X-rayphotoelectronspectroscopy(XPS)indicatedthatthe O1s peakconsistofthreecomponents:O1(ZnO),O2(deficient oxygen;OHgroups)andO3(adsorbed species) centredat530.3,531.2and532.6eV,respectively.Abroadorange-redemissionfrom500to 850 nmwasobtainedfromtheZnONPrpreparedwiththenitrateprecursorwhichmaybeattributedto different kindsofdefects,andasharpUVband,duetothepossiblepassivationofdefects,at392nmfrom ZnO NPrpreparedwithacetateprecursor.

A new naturally occurring compound based on the dammarane skeleton, i.e. cabralealactone 3-acetate-24-methyl ether, was isolated from the aqueous methanolic extract of Forsythia koreana fruits, along with eight known compounds: cabralealactone 3-acetate, ursolic acid, arctigenin, arctiin, phillyrin, rutin, caffeic acid, and rosmarinic acid. The identification of the isolated compounds was based on their spectral analysis including: HREI-MS, 1D and 2D NMR spectroscopy. The selected compounds and the aqueous methanolic extract were evaluated for their cytotoxic activity against human solid tumour cell lines. Cabralealactone 3-acetate-24-methyl ether and ursolic acid were found to be active against human breast cancer cells (MCF-7). The cytotoxicity was associated with the activation of caspase-8, the induction of the death receptors DR4 and DR5, as well as DNA fragmentation, and was thus due to apoptosis rather than necrosis.

High Energy Physics (HEP) targeting on particle physics, searches for the fundamental par‐ ticles and forces which construct the world surrounding us and understands how our uni‐ verse works at its most fundamental level. Elementary particles of the Standard Model are gauge Bosons (force carriers) and Fermions which are classified into two groups: Leptons (i.e. Muons, Electrons, etc) and Quarks (Protons, Neutrons, etc).

In this study, white cathodoluminescence (CL) was generated from Zn0.3Mg0.7Al2O4:Tb3+;Eu3+ prepared by the combustion route using urea as a fuel metal and nitrates as precursors. The X-ray diffraction (XRD) patterns from the samples showed phases associated with cubic structures of ZnAl2O4 and MgAl2O4. The particle morphology of the Zn0.3Mg0.7Al2O4:Tb3+;Eu3+ showed different irregular shapes. White CL with the CIE coordinates (x = 0.343, y = 0.323) was observed when the phosphor was excited by a low voltage (2 keV) electron beam in vacuum. This was a result of the simultaneous emission of blue and green emissions from Tb3+, and red emission from Eu3+. This phosphor is evaluated for possible applications in white LEDs. . The authors would like to acknowledge the financial support from the cluster funds of the University of the Free State, the South African National Research Foundation (NRF), the South African National Laser centre (NLC), and the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation of South Africa. In this study, white cathodoluminescence (CL) was generated from Zn0.3Mg0.7Al2O4:Tb3+;Eu3+ prepared by the combustion route using urea as a fuel metal and nitrates as precursors. The X-ray diffraction (XRD) patterns from the samples showed phases associated with cubic structures of ZnAl2O4 and MgAl2O4. The particle morphology of the Zn0.3Mg0.7Al2O4:Tb3+;Eu3+ showed different irregular shapes. White CL with the CIE coordinates (x = 0.343, y = 0.323) was observed when the phosphor was excited by a low voltage (2 keV) electron beam in vacuum. This was a result of the simultaneous emission of blue and green emissions from Tb3+, and red emission from Eu3+. This phosphor is evaluated for possible applications in white LEDs. .

A white light emitting CaxSr1-xAl2O4:Tb3+;Eu3+ phosphor was synthesized by a combustion method using metal nitrates as precursors and urea as a fuel. The X-ray diffraction patterns from the samples showed phases associated with monoclinic structures of CaAl2O4 and SrAl2O4. White photoluminescence with the CIE coordinates (x = 0.343, y = 0.325) was observed when the phosphor was optically-excited at 227 nm using a monochromatized xenon lamp. The white photoluminescence was a result of the combination of blue and green line emissions from Tb3+, and red line emission from Eu3+. The structure and photoluminescence properties of this phosphor are reported. The authors would like to acknowledge the financial support from the cluster funds of the University of the Free State and the South African National Research Foundation. A white light emitting CaxSr1-xAl2O4:Tb3+;Eu3+ phosphor was synthesized by a combustion method using metal nitrates as precursors and urea as a fuel. The X-ray diffraction patterns from the samples showed phases associated with monoclinic structures of CaAl2O4 and SrAl2O4. White photoluminescence with the CIE coordinates (x = 0.343, y = 0.325) was observed when the phosphor was optically-excited at 227 nm using a monochromatized xenon lamp. The white photoluminescence was a result of the combination of blue and green line emissions from Tb3+, and red line emission from Eu3+. The structure and photoluminescence properties of this phosphor are reported.

White light was produced from CaAl2O4 nanophosphor co-doped with Tb3+and Eu3+. The short time and low temperature reaction combustion route was used to synthesize CaAl2O4:Tb3+,Eu3+ nanophosphors using metal nitrates precursors and urea as fuel. The crystalline structure and particle morphology were using XRD and SEM respectively. The optical properties were studied by Photoluminescence (PL) spectroscopy and the UV-Vis spectrometer in the range 800-200 nm. The excitation spectra were recorded by monitoring the three main emissions, namely blue at 438nm, green at 543nm and red at 617 nm.. 227nm was found to be the most suitable excitation wavelength to generate, simultaneously, blue and green emission from Tb3+ and red emission from Eu3+ whose combination constituted white light. The blue and green were respectively attributed to the 4f-4f transitions of Tb3+ by 5D3–7FJ (J= 6-2) and 5D4→7FJ (J = 0-6) while the red emission was attributed to 5D0→7FJ (J=0-4) transitions of Eu3+. Preliminary results on the structure and photoluminescent properties of this phosphor are reported. The authors send gratitude to the National Research Foundation (NRF) for funding the project and the Cluster program of the University of the Free State. White light was produced from CaAl2O4 nanophosphor co-doped with Tb3+and Eu3+. The short time and low temperature reaction combustion route was used to synthesize CaAl2O4:Tb3+,Eu3+ nanophosphors using metal nitrates precursors and urea as fuel. The crystalline structure and particle morphology were using XRD and SEM respectively. The optical properties were studied by Photoluminescence (PL) spectroscopy and the UV-Vis spectrometer in the range 800-200 nm. The excitation spectra were recorded by monitoring the three main emissions, namely blue at 438nm, green at 543nm and red at 617 nm.. 227nm was found to be the most suitable excitation wavelength to generate, simultaneously, blue and green emission from Tb3+ and red emission from Eu3+ whose combination constituted white light. The blue and green were respectively attributed to the 4f-4f transitions of Tb3+ by 5D3–7FJ (J= 6-2) and 5D4→7FJ (J = 0-6) while the red emission was attributed to 5D0→7FJ (J=0-4) transitions of Eu3+. Preliminary results on the structure and photoluminescent properties of this phosphor are reported.

This book contains some of the magnetic, the electric and the dielectric properties of the mixed Cu-Zn spinel ferrite. The material covered in this book is divided into two parts: They are theoretical part I and experimental part II. Part I contains six chapters, that cover description of magnetic materials in chapter 1, structure properties of ferrimagnetic materials in chapter 2, magnetic properties of ferrimagnetic materials in chapter 3 , electric and dielectric properties of ferrimagnetic materials in chapter 4, applications of ferrimagnetic materials in chapter 5 and finally literature survey in chapter 6. Part II divides into four chapters that describe method, techniques, and results. These chapters, also, discuss the structure of the mixed Cu-Zn spinel ferrite and the effects of the 2 Zn ions of the mixed Cu-Zn spinel ferrite on magnetic, the electric and the dielectric properties. Chapter 7 covers of the preparation of mixed Cu-Zn spinel ferrite, which have the chemical formula 1 s s 2 4 Cu Zn Fe O  , where s stepped by 0.2 according to Advanced Ferrite Technology Preface ix ( 0.0  s 1.0), were prepared from purity metal oxides using the standard ceramic. It, also, exhibits the experimental techniques and the apparatus for different measurements. Chapter 8 illustrates the infrared IR spectra for the ferrite samples in the frequency range 1 (200 1000)   cm . Two main absorption bands were observed which indicate the formation of spinel ferrite compound. In addition, two small absorption bands were, also, observed. Their positions and intensities were found to be strongly depending on the s-value. On the basis of the IR spectra analyzation, the crystal structure and cations distribution were deduced for the ferrite samples. Chapter 9 covers the magnetic properties for the ferrite samples using Faraday’s law of the electromagnetic induction. The ferrite samples were used to find the magnetization at room temperature in the range of the applied magnetic field which was varied from 0 1 .  Am up to 510 1 .  Am . The obtained results illustrate that, as the 2 Zn ions increased the magnetization increasing for the ferrite samples with s  0.6 , where it decreased for the ferrite samples with s > 0.6. The observed results of the magnetic properties were in good agreement with several studies for various ferrite compounds [1-3]. We adapted Yafet and Kittel model [4] and Neel’s theory [5] to explain the observed results. The initial permeability for the ferrite samples was determined as a function of temperature. It increased with increasing of temperature, then, it decreased abruptly close to Curie temperature point. Utilizing the initial permeability data, the Curie temperature points were estimated for all the ferrite samples. It decreased by the addition of the 2 Zn Advanced Ferrite Technology Preface x ions. The magnetic properties were found to be affected by the intensity of the applied magnetic field, the s-value and temperature. Finally, chapter 10 exhibits the AC conductivity for the ferrite samples in the applied frequency of the range(10 10 )Hz 4 6  . In this range frequency, the AC conductivity increased continuously with increasing of the applied frequency. The dielectric properties for the ferrite samples were determined at room temperature as a function of the applied frequency in the range(10 10 )Hz 4 6  . The general trend for all samples was found to decrease continuously with increasing of the applied frequency. The DC resistivity was determined for the ferrite samples in temperature range which varied from 300K up to 730K. The variation of the logarithm of resistivity DC ln  with the reciprocal of temperature (1/T) showed that, resistivity continuously decreased with increasing of temperature. On the other hand, the plot of DC ln  versus (1/T) indicated more than one slope. This change of the slope is attributed to the existence of different competing conduction mechanisms. The measurements of the electric and the dielectric properties exhibited that, the behavior of the ferrite samples is the same as that of the semiconductor materials. The results of the electric and dielectric properties were in good agreement with previous studies for various ferrite compounds [6-10]. The electron hopping model [11] was used to explain the electric conductivity for the ferrite samples. The electric and the dielectric properties were found to be affected by the s-value, temperature and frequency of the applied magnetic field. Advanced Ferrite Technology Preface xi This book exhibited that, the non-magnetic 2 Zn ions have great effects on the magnetic, the electric and the dielectric properties of the Cu spinel ferrite. In the light of the different theories and results of chapters in the part I and II the prominent properties of ferrites make them very promising a candidate versatile. A study of polycrystalline ferrites is important in view of their successively extensively used as core materials over a wide range of frequency for numerous electronic devices and electrical components. This is due to their high initial permeability, large resistivity, high dielectric constant and low dielectric loss. In fact, the mixed Cu-Zn spinel ferrite is considered a soft ferrite material, which is proved to be an interest material for technological and scientific applications. This book contains some of the magnetic, the electric and the dielectric properties of the mixed Cu-Zn spinel ferrite. The material covered in this book is divided into two parts: They are theoretical part I and experimental part II. Part I contains six chapters, that cover description of magnetic materials in chapter 1, structure properties of ferrimagnetic materials in chapter 2, magnetic properties of ferrimagnetic materials in chapter 3 , electric and dielectric properties of ferrimagnetic materials in chapter 4, applications of ferrimagnetic materials in chapter 5 and finally literature survey in chapter 6. Part II divides into four chapters that describe method, techniques, and results. These chapters, also, discuss the structure of the mixed Cu-Zn spinel ferrite and the effects of the 2 Zn ions of the mixed Cu-Zn spinel ferrite on magnetic, the electric and the dielectric properties. Chapter 7 covers of the preparation of mixed Cu-Zn spinel ferrite, which have the chemical formula 1 s s 2 4 Cu Zn Fe O  , where s stepped by 0.2 according to Advanced Ferrite Technology Preface ix ( 0.0  s 1.0), were prepared from purity metal oxides using the standard ceramic. It, also, exhibits the experimental techniques and the apparatus for different measurements. Chapter 8 illustrates the infrared IR spectra for the ferrite samples in the frequency range 1 (200 1000)   cm . Two main absorption bands were observed which indicate the formation of spinel ferrite compound. In addition, two small absorption bands were, also, observed. Their positions and intensities were found to be strongly depending on the s-value. On the basis of the IR spectra analyzation, the crystal structure and cations distribution were deduced for the ferrite samples. Chapter 9 covers the magnetic properties for the ferrite samples using Faraday’s law of the electromagnetic induction. The ferrite samples were used to find the magnetization at room temperature in the range of the applied magnetic field which was varied from 0 1 .  Am up to 510 1 .  Am . The obtained results illustrate that, as the 2 Zn ions increased the magnetization increasing for the ferrite samples with s  0.6 , where it decreased for the ferrite samples with s > 0.6. The observed results of the magnetic properties were in good agreement with several studies for various ferrite compounds [1-3]. We adapted Yafet and Kittel model [4] and Neel’s theory [5] to explain the observed results. The initial permeability for the ferrite samples was determined as a function of temperature. It increased with increasing of temperature, then, it decreased abruptly close to Curie temperature point. Utilizing the initial permeability data, the Curie temperature points were estimated for all the ferrite samples. It decreased by the addition of the 2 Zn Advanced Ferrite Technology Preface x ions. The magnetic properties were found to be affected by the intensity of the applied magnetic field, the s-value and temperature. Finally, chapter 10 exhibits the AC conductivity for the ferrite samples in the applied frequency of the range(10 10 )Hz 4 6  . In this range frequency, the AC conductivity increased continuously with increasing of the applied frequency. The dielectric properties for the ferrite samples were determined at room temperature as a function of the applied frequency in the range(10 10 )Hz 4 6  . The general trend for all samples was found to decrease continuously with increasing of the applied frequency. The DC resistivity was determined for the ferrite samples in temperature range which varied from 300K up to 730K. The variation of the logarithm of resistivity DC ln  with the reciprocal of temperature (1/T) showed that, resistivity continuously decreased with increasing of temperature. On the other hand, the plot of DC ln  versus (1/T) indicated more than one slope. This change of the slope is attributed to the existence of different competing conduction mechanisms. The measurements of the electric and the dielectric properties exhibited that, the behavior of the ferrite samples is the same as that of the semiconductor materials. The results of the electric and dielectric properties were in good agreement with previous studies for various ferrite compounds [6-10]. The electron hopping model [11] was used to explain the electric conductivity for the ferrite samples. The electric and the dielectric properties were found to be affected by the s-value, temperature and frequency of the applied magnetic field. Advanced Ferrite Technology Preface xi This book exhibited that, the non-magnetic 2 Zn ions have great effects on the magnetic, the electric and the dielectric properties of the Cu spinel ferrite. In the light of the different theories and results of chapters in the part I and II the prominent properties of ferrites make them very promising a candidate versatile. A study of polycrystalline ferrites is important in view of their successively extensively used as core materials over a wide range of frequency for numerous electronic devices and electrical components. This is due to their high initial permeability, large resistivity, high dielectric constant and low dielectric loss. In fact, the mixed Cu-Zn spinel ferrite is considered a soft ferrite material, which is proved to be an interest material for technological and scientific applications.

Tb3+ doped Zn0.5Sr0.5Al2O4 (ZSAO) nanocrystalline phosphor was successfully synthesized by a combustion method at a relatively low temperature (500oC), using metal nitrates as precursors and urea as a fuel. The samples were annealed in air at 700oC for 4 hrs. The X-ray diffraction patterns showed phases associated with both ZnAl2O4 (ZAO) and SrAl2O4 ( SAO) as referenced to standard JCPDS data files No. 05-0669 and 74-794, respectively. As confirmed from the scanning electron microscopy images, the characteristic platelet-like particles of the combustion method were formed. The photoluminescence emission and excitation spectra of Zn0.5Sr0.5Al2O4:Tb3+ before and after annealing were recorded and compared to those of ZnAl2O4:Tb3+ and SrAl2O4:Tb3+. In all cases, PL emissions were due to 5D4→7FJ (J = 0,1,2,3,4,5,6) transitions of Tb3+. The PL emissions of ZnAl2O4:Tb3+ and SrAl2O4:Tb3+ were more intense than that of Zn0.5Sr0.5Al2O4:Tb3+. The objective of the study was to prepare a new aluminate host for Tb3+ consisting of Zn and Sr and evaluate its luminescent properties and chemical study for application in lighting. The authors are grateful to the financial support from the South African National Research Foundation (NRF). Tb3+ doped Zn0.5Sr0.5Al2O4 (ZSAO) nanocrystalline phosphor was successfully synthesized by a combustion method at a relatively low temperature (500oC), using metal nitrates as precursors and urea as a fuel. The samples were annealed in air at 700oC for 4 hrs. The X-ray diffraction patterns showed phases associated with both ZnAl2O4 (ZAO) and SrAl2O4 ( SAO) as referenced to standard JCPDS data files No. 05-0669 and 74-794, respectively. As confirmed from the scanning electron microscopy images, the characteristic platelet-like particles of the combustion method were formed. The photoluminescence emission and excitation spectra of Zn0.5Sr0.5Al2O4:Tb3+ before and after annealing were recorded and compared to those of ZnAl2O4:Tb3+ and SrAl2O4:Tb3+. In all cases, PL emissions were due to 5D4→7FJ (J = 0,1,2,3,4,5,6) transitions of Tb3+. The PL emissions of ZnAl2O4:Tb3+ and SrAl2O4:Tb3+ were more intense than that of Zn0.5Sr0.5Al2O4:Tb3+. The objective of the study was to prepare a new aluminate host for Tb3+ consisting of Zn and Sr and evaluate its luminescent properties and chemical study for application in lighting.

A new very sensitive and selective chromogenic reagents prepared by the reaction of Schiff base with maleic anhydride (MA) and 1,4-butane (I), ethylene (II), 1,6-hexamethylene (III) and 1,2-propane diol (IV), respectively, were synthesized and studied for the determination of trace lead in detail. In 0.1molL−1 NaOH medium, lead reacts with polyester to form a yellow complex, which gives a maximum absorption at 462, 478, 482 and 495 nm using I, II, III and IV respectively. Beer’s law is obeyed over the concentration ranges 0.04-1.20μgmL−1, whereas optimum concentration ranges as adopted from Ringbom method was 0.10-1.05μgmL−1. The molar absorptivity, Sandell sensitivity, detection and quantifi cation limits are also calculated Ca (3500-fold), Mg (2250-fold), Sr (1250-fold), Ba (1000-fold), Al (1500-fold), Bi (800-fold), Fe (2500-fold) Co (1100-fold), Ni (1000-fold), Cu (900-fold), Zn (1300-fold), Cd (2500-fold), and Ag (750-fold) do not interfere with the determination of lead. The chromogenic system is remarkably superior to other reagents, especially porphyrin compounds. The influence caused by oxygen in air or in solution can be easily eliminated by adding Na2SO3. The reaction is very stable, the stability constant of the complex being 1.44 x 1045. The chromogenic reaction is completed within 2.0 min at room temperature. The proposed method has been applied to the direct determination of trace lead in clinical samples. The accuracy and precision are both very satisfactory.

In this work, we have studied the effects of the 2 Zn ions on the electric and the dielectric properties of the Cu spinel ferrite. The mixed Cu-Zn spinel ferrite, of chemical formula 1 s s 2 4 Cu Zn Fe O  , where s stepped by 0.2 according to ( 0.0 s 1.0), were prepared from purity metal oxides using the standard ceramic preparation. The AC conductivity was determined for the ferrite samples in the applied frequency range (10 10 )Hz 4 6  . In this range of frequency, the AC conductivity increases rapidly as a function of the applied frequency. The dielectric properties for the ferrite samples were also determined at room temperature. The general trend for all samples was found to decrease continuously with increasing of the applied frequency. The measurements of the electric and the dielectric properties show that, the behavior of the ferrite samples is similar to that of the semiconductor materials. The results of the electric and dielectric properties are inadequate to previous studies for various ferrite compounds. The electric conductivity for the samples was explained using the electron hopping model. In this work, we have studied the effects of the 2 Zn ions on the electric and the dielectric properties of the Cu spinel ferrite. The mixed Cu-Zn spinel ferrite, of chemical formula 1 s s 2 4 Cu Zn Fe O  , where s stepped by 0.2 according to ( 0.0 s 1.0), were prepared from purity metal oxides using the standard ceramic preparation. The AC conductivity was determined for the ferrite samples in the applied frequency range (10 10 )Hz 4 6  . In this range of frequency, the AC conductivity increases rapidly as a function of the applied frequency. The dielectric properties for the ferrite samples were also determined at room temperature. The general trend for all samples was found to decrease continuously with increasing of the applied frequency. The measurements of the electric and the dielectric properties show that, the behavior of the ferrite samples is similar to that of the semiconductor materials. The results of the electric and dielectric properties are inadequate to previous studies for various ferrite compounds. The electric conductivity for the samples was explained using the electron hopping model.

A new pyranone derivative, 3-hydroxy-2-(4-hydroxyphenyl)-6-methyl-4H-pyran-4-one (1), was isolated from the leaves of Livistona australis. The structure was determined by NMR spectral analysis.

Familial cold autoinflammatory syndrome (FCAS) is a rare, hereditary disorder characterized by cold-induced inflammation. We describe the successful longterm treatment of a patient with FCAS with anakinra, an interleukin 1 receptor antagonist (IL-1Ra). The remarkable response of FCAS and associated Raynaud's disease in this patient suggests that IL-1 is an important mediator of these inflammatory diseases. Our report supports increasing evidence that anakinra plays an important role in the treatment of select chronic inflammatory diseases.

The Cu-Zn ferrites samples have the general formula Cu1-sZnsFe2O4, (where s is stepped by 0.2 according to 0.0s1.0), The samples are used to measure the magnetization at room temperature. The magnetization increases with the increase of zinc ions up to 60%, and then it decreases with further addition of zinc ions. The increase of the sample magnetization is explained on the basis of Néel’s two sub-lattice model, while the decrease in the magnetization beyond s = 0.6 was attributed to the presence of a triangular spin arrangement on octahedral Oh sites; and was explained by the three sub-lattice model suggested by Yafet and Kittle. The magnetic moment for tetrahedral Tdsites and octahedral Oh sites were calculated according to the suggested cations distribution (Zns2+ Fe1-s3+)Td {Cu1-s2+ Fe1+s3+}Oh O42-.The relative permeability µr is calculated for the above-mentioned samples. The Cu-Zn ferrites samples have the general formula Cu1-sZnsFe2O4, (where s is stepped by 0.2 according to 0.0s1.0), The samples are used to measure the magnetization at room temperature. The magnetization increases with the increase of zinc ions up to 60%, and then it decreases with further addition of zinc ions. The increase of the sample magnetization is explained on the basis of Néel’s two sub-lattice model, while the decrease in the magnetization beyond s = 0.6 was attributed to the presence of a triangular spin arrangement on octahedral Oh sites; and was explained by the three sub-lattice model suggested by Yafet and Kittle. The magnetic moment for tetrahedral Tdsites and octahedral Oh sites were calculated according to the suggested cations distribution (Zns2+ Fe1-s3+)Td {Cu1-s2+ Fe1+s3+}Oh O42-.The relative permeability µr is calculated for the above-mentioned samples.

Infrared (IR) spectra of Zn2+ ions substituted Cu spinel ferrite, having the general formula Cu1-sZnsFe2O4, (where s stepped by 0.2 such that0.0s1.0), have been analyzed in the frequency range(200-1000)cm-1. The above mixed ferrites were prepared by the conventional standard double sintering ceramic method. Four absorption bands were observed, their position and intensity were found to be strongly dependent on s-value. Mainly, two prominent bands were observed, a high frequency band νT at around (536-568) cm-1 and a low frequency band νO at around (394) cm-1 were assigned to tetrahedral Td and octahedral Oh sites, respectively, of spinel lattice.Upon introducing Zn2+ions, IR spectra indicated new shoulders or splitting in the absorption bands, such the first primary band νT which consists of two shoulders at about (700 and 600)cm-1. A small absorption band ν3 was observed at about (300-325) cm-1. This may indicate the presence of the divalent metal ion-oxygen complex on Oh sites. Other small weak absorption band ν4 was, also, observed at about (265-270) cm-1. Its intensity increased with the addition of Zn2+ions. Force constant FC was calculated for Td and Oh sites, and was found to decrease with increasing Zn2+ ions. Half band widths of Td sites (ΓT) and Oh sites (ΓO) changed linearly with increasing Zn2+ ions. Threshold frequency νth for the electronic transition was determined and found to increase with increasing Zn2+ions. On the basis of the analysis of IR absorption bands, we concluded the cations distribution for the given mixed ferrite. The ionic radii for each site were correlated to the cations distribution of the given ferrite. Infrared (IR) spectra of Zn2+ ions substituted Cu spinel ferrite, having the general formula Cu1-sZnsFe2O4, (where s stepped by 0.2 such that0.0s1.0), have been analyzed in the frequency range(200-1000)cm-1. The above mixed ferrites were prepared by the conventional standard double sintering ceramic method. Four absorption bands were observed, their position and intensity were found to be strongly dependent on s-value. Mainly, two prominent bands were observed, a high frequency band νT at around (536-568) cm-1 and a low frequency band νO at around (394) cm-1 were assigned to tetrahedral Td and octahedral Oh sites, respectively, of spinel lattice.Upon introducing Zn2+ions, IR spectra indicated new shoulders or splitting in the absorption bands, such the first primary band νT which consists of two shoulders at about (700 and 600)cm-1. A small absorption band ν3 was observed at about (300-325) cm-1. This may indicate the presence of the divalent metal ion-oxygen complex on Oh sites. Other small weak absorption band ν4 was, also, observed at about (265-270) cm-1. Its intensity increased with the addition of Zn2+ions. Force constant FC was calculated for Td and Oh sites, and was found to decrease with increasing Zn2+ ions. Half band widths of Td sites (ΓT) and Oh sites (ΓO) changed linearly with increasing Zn2+ ions. Threshold frequency νth for the electronic transition was determined and found to increase with increasing Zn2+ions. On the basis of the analysis of IR absorption bands, we concluded the cations distribution for the given mixed ferrite. The ionic radii for each site were correlated to the cations distribution of the given ferrite.

Metastatic spread of malignancy to the joints is rare and only a few cases of solid tumors have been reported. We describe a patient with inflammatory arthritis of the knee and ankle secondary to metastatic gastric adenocarcinoma to the joints and bone diagnosed by synovianalysis. Arthritis secondary to metastatic cancer is a poor prognostic sign. The diagnosis is based on a strong clinical suspicion, magnetic resonance imaging, and joint fluid cytology or synovial biopsy.

Highly c-axis oriented wurtzite structured ZnO thin films were deposited on silicon substrates using pulsed laser deposition (PLD) by ablating a ZnO target in different atmospheres, including vacuum, argon and oxygen in the deposition chamber. The stress in the films was shown to vary from −3.83 to −0.03 GPa as a function of the chamber atmosphere. The minimum compressive stress (−0.03 GPa) was observed for the oxygen atmosphere. X-ray photoelectron spectroscopy data indicated that the O1s peak consists of three components designated as O1 (due to ZnO), O2 (due to defects) and O3 (due to adsorbed species). A small defect level emission was obtained in the luminescence spectra of the ZnO film deposited in the oxygen atmosphere, while strong ultraviolet (UV) emission was observed for the ZnO films deposited in the vacuum and argon atmosphere. These PLD grown ZnO thin films have the potential to be used as sources of UV radiation in light emitting devices. The authors want to thank to the National Laser Centre, CSIR, Pretoria for providing pulsed laser deposition technique. This work is based on the research supported by the South African Research Chairs Initiative of the Department of Science and Technology, and the National Research Foundation of South Africa. The PL system used in this study is supported both technically and financially by the rental pool programme of the National Laser Centre. The financial support from the Cluster program of the University of the Free State is highly recognized. Highly c-axis oriented wurtzite structured ZnO thin films were deposited on silicon substrates using pulsed laser deposition (PLD) by ablating a ZnO target in different atmospheres, including vacuum, argon and oxygen in the deposition chamber. The stress in the films was shown to vary from −3.83 to −0.03 GPa as a function of the chamber atmosphere. The minimum compressive stress (−0.03 GPa) was observed for the oxygen atmosphere. X-ray photoelectron spectroscopy data indicated that the O1s peak consists of three components designated as O1 (due to ZnO), O2 (due to defects) and O3 (due to adsorbed species). A small defect level emission was obtained in the luminescence spectra of the ZnO film deposited in the oxygen atmosphere, while strong ultraviolet (UV) emission was observed for the ZnO films deposited in the vacuum and argon atmosphere. These PLD grown ZnO thin films have the potential to be used as sources of UV radiation in light emitting devices.

A white light emitting CaxSr1-xAl2O4:Tb3+;Eu3+ phosphor was synthesized by a combustion method using metal nitrates as precursors and urea as a fuel. The X-ray diffraction patterns from the samples showed phases associated with monoclinic structures of CaAl2O4 and SrAl2O4. White photoluminescence with the CIE coordinates (x = 0.343, y = 0.325) was observed when the phosphor was optically-excited at 227 nm using a monochromatized xenon lamp. The white photoluminescence was a result of the combination of blue and green line emissions from Tb3+, and red line emission from Eu3+. The structure and photoluminescence properties of this phosphor are reported.