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1.
J Phys Condens Matter ; 35(12)2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36603224

ABSTRACT

Here we report the evidence of an additional magnetic ordering and frequency dispersive magneto-dielectric (MD) permittivity besides multiferroic behavior in Te4+(S= 0) doped FeVO4. Two antiferromagnetic transitions similar to FeVO4at ∼21.86 K (TN1) and 16.03 K (TN2) were observed in all samples. An additional novel defect clusters based magnetic ordering at relatively higher temperature (TAMO) ∼ 203 K is also observed from the magnetization. Evaluated magnetic moments show systematic decrease and the magnetic frustration factors show an increase with the increasing of Te4+(S= 0) content. MD studies show stable ferroelectric ordering at spiral magnetic transition (TN2) and the multiferroic order persists to the largest doping of Te (x= 0.10). The MD studies also reveal a magneto-capacitive (MC) behavior at TAMO(∼203 K) with a high dielectric constant and loss, and the possible reason for the magnetic ordering and MC behavior is ascribed to short range magnetic clustering arising out of defect based mechanisms. Mössbauer spectroscopic studies confirm local structural correlation with magnetic and ferroelectric ordering.

2.
Article in English | MEDLINE | ID: mdl-34874279

ABSTRACT

In this work, we investigated the effect of Ag doping (2-20 at.%) on the phase formation of iron mononitride (FeN) thin films. Together with deposition of FeN using reactive dc magnetron sputtering, Ag was also co-sputtered at various doping levels between 2-20 at.%. We found that doping of Ag around 5 at.% is optimum to not only improve the thermal stability of FeN but also to reduce intrinsic defects that are invariably present in (even in epitaxial) FeN. Conversion electron Mössbauer spectroscopy and N K-edge x-ray near edge absorption measurements clearly reveal a reduction of defects in Ag doped FeN samples. Moreover, Fe self-diffusion measurements carried out using secondary ion mass spectroscopy depth-profiling and polarized neutron reflectivity in57Fe enriched samples exhibit an appreciable reduction in Fe self-diffusion in Ag doped FeN samples. Ag being immiscible with Fe and non-reactive with N, occupies grain-boundary positions as nanoparticles and prohibits the fast Fe self-diffusion in FeN.

3.
J Phys Condens Matter ; 33(33)2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34107463

ABSTRACT

We report the complex implications of inter-diffusion between polycrystalline FePt/FeCo layers as an impact of the FeCo underlayer on the structural and magnetic properties of the system. The crystalline growth of FePt strongly reduces in an entirely diffused system compared to the one with lesser diffusion, while the crystalline structure of FeCo is apparently less affected. Charge redistribution occurs between Fe, Co and Pt ensuring increased Co-Pt and Fe-Pt interactions with higher diffusion. Thereafter, we combine hysteresis and magnetic force microscopy measurements to show that the interfacial deformations result in the distinct out-plane magnetic behaviour of the system. FeCo@FePt nano-composite like structure, originating due to interfacial diffusion, shows interactions between two magnetic phases with in-plane low anisotropy exhibiting wasp-shaped out-plane hysteresis loop. Whereas the layered structure of FePt/FeCo films shows random anisotropy with a significant out-plane contribution even in the polycrystalline films. Micromagnetic modelling demonstrates coercivity deterioration and reduction of switching field due to the formation of a slightly diffused interface. Contrarily, the experimental observations for complete diffusion between the two layers are explained by simulating the inhomogeneous distribution of anisotropies along the film plane. These studies provide deep perceptions of the magnetic properties of FePt/FeCo system governed by diffusion kinetics which are valuable to achieve desired magnetic characteristics using this system.

4.
J Phys Condens Matter ; 32(30): 305501, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32217827

ABSTRACT

Enhanced magnetic moment and coercivity in SrRuO3 thin films are significant issues for advanced technological usages and hence are researched extensively in recent times. Most of the previous reports on thin films with enhanced magnetic moment attributed it to the high spin state. Our magnetization results show high magnetic moment of 3.3 µB/Ru ion in the epitaxial thin films grown on LSAT substrate against 1.2 µB/Ru ion observed in bulk compound. Contrary to the previous reports the Ru ions are found to be in low spin state and the orbital moment is shown to be contributing significantly in the enhancement of magnetic moment. We employed x-ray absorption spectroscopy and resonant valance band spectroscopy to probe the spin state and orbital contributions in these films. The existence of strong spin-orbit coupling responsible for the de-quenching of the 4d orbitals is confirmed by the observation of the non-statistical large branching ratio at the Ru M2,3 absorption edges. X-ray magnetic circular dichroism studies performed at the Ru M2,3 edges provided direct evidence of significant contribution of orbital moment in the film grown on LSAT. The relaxation of orbital quenching by strain engineering provides a new tool for enhancing magnetic moment and strain disorder is shown to be an efficient mean to control the spin-orbit coupling.

5.
Nanotechnology ; 31(28): 285708, 2020 Mar 26.
Article in English | MEDLINE | ID: mdl-32213684

ABSTRACT

Cubic spinel CoCr2O4 has recently attained attention due to its multiferroic properties. However, the Co site substitution effect on the structural and magnetic properties has rarely been studied in thin film form. In this work, the structural and magnetic properties of Co1-x Ni x Cr2O4 (x= 0, 0.5) epitaxial thin films deposited on MgAl2O4 (100) and MgO (100) substrates to manipulate the nature of strain in the films using pulsed laser deposition (PLD) technique are presented. The epitaxial nature of the films was manifested through x-ray diffraction (XRD), reciprocal space mapping (RSM) and Rutherford backscattering spectrometry (RBS) measurements. Raman measurements revealed a disappearance of characteristic A 1 g and F 2 g modes of the CoCr2O4 with increase in the Ni content. Atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM) studies show a modification of the surface morphology upon Ni substitution. Magnetic measurements disclose that the ferrimagnetic Curie temperature (T C) of the CoCr2O4 in thin film grown on MgAl2O4 (100) and MgO (100) substrates were found to be 100.6 ± 0.5 K and 93.8 ± 0.2 K, respectively. With Ni substitution the T C values were found to be enhanced to 104.5 ± 0.4 K for MgAl2O4 (100) and 108.5 ± 0.6 K for MgO (100) substrates. X-ray photoelectron spectroscopy (XPS) suggests Cr3+ oxidation states in the films, while Co ions are present in a mixed Co2+/Co3+ oxidation state. The substitution of Ni at Co site significantly modifies the line shape of the core level as well as the valence band. Ni ions are also found to be in a mixed 2+/3+ oxidation state. O 1s core level display asymmetry related to possible defects like oxygen vacancies in the films.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117668, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31703993

ABSTRACT

The present manuscript reports vibrational spectra and optical studies of polycrystalline Fe1-xCrxVO4 solid solutions through FT-IR spectroscopy augmented with a group theory (G.T.) analysis and UV-Visible DRS spectroscopy. Full set of IR and Raman modes are determined by G. T. for various crystal symmetries in FeVO4-CrVO4 solid solutions where Triclinic, Monoclinic and Orthorhombic structures evolve with increasing Cr concentration. Experimentally obtained vibrational modes support the structural phase transitions and confirm formation of continuous solid solutions in Fe1-xCrxVO4. The Diffuse Reflectance Spectra (DRS) of Fe1-xCrxVO4 depicts the electronic structure and different optical transitions due to absorption of photon energy. The d-d transitions are manifested for all compounds in terms of crystal field stabilization energy (CFSE) caused by distorted lattice sites. The band gap energy of Fe1-xCrxVO4 is calculated using Tauc formula. It shows a red shift initially within triclinic structure then blue shift with the increase of Cr concentration. Urbach energy (Eu) tails in the spectra show the electronic structural disorder in Fe1-xCrxVO4 due to impurity energy levels of Cr ions within band gap region. It is observed that Eu decreases with the doping concentration due to the increase in crystal symmetry corresponding to the structural phase transitions in Fe1-xCrxVO4.

7.
Phys Chem Chem Phys ; 21(27): 15019-15029, 2019 Jul 10.
Article in English | MEDLINE | ID: mdl-31241072

ABSTRACT

Herein, we present defect-induced photoluminescence behavior of Ga-doped ZnO (GZO) thin films with varying doping (Ga) concentrations and energetic ion irradiation. The Ga-doped ZnO thin films were prepared by a sol-gel spin-coating method. Micro-photoluminescence (µ-PL) was carried out to investigate the defect-related emission with the variation of doping concentration and ion irradiation. The PL spectra revealed that all films showed near-band-edge (NBE) emission along with a broad visible emission band, consisting of violet, blue, green, and yellow emission bands. The intensity of these emission bands was found to be strongly dependent on the Ga doping concentration and ion irradiation. Interestingly, a pronounced violet emission band around 2.99 eV (415 nm) was observed for the Ga-doped ZnO thin films with high Ga doping concentration, whereas an irradiated film with high ion fluence exhibited a strong green emission around 2.39 eV (519 nm); however, we concluded that the violet emission might have originated from zinc interstitial defects (Zni), and the concentration of Zni increased with the increasing doping concentration. The green emission is ascribed to the oxygen vacancies (VO), and the concentration of the VO defects increases with the increasing ion fluence. Thus, the µ-PL spectra of the irradiated films with emission dominating in the blue and green regions could be attributed to the formation of extended defects such as clusters and ionizing centers of Zni and VO. Herein, an in-depth understanding of the variation in defects related to the emission bands from these films is reported and correlated with the transport properties of these films for their possible optoelectronic applications.

8.
Animal ; 10(6): 1007-15, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27076348

ABSTRACT

Understanding of biological impact of proteome profile on meat quality is vital for developing different approaches to improve meat quality. Present study was conducted to unravel the differences in biochemical, ultrastructural and proteome profile of longissimus dorsi muscle between buffaloes (Bubalus bubalis) of different age groups (young v. old). Higher (P<0.05) myofibrillar and total protein extractability, muscle fibre diameter, and Warner-Bratzler shear force (WBSF) values was observed in old buffalo meat relative to meat from young buffaloes. Scanning electron microscopy photographs revealed reduced fibre size with increased inter-myofibrillar space in young compared with old buffalo meat. Transmission electron microscopy results revealed longer sarcomeres in young buffalo meat relative to meat from old buffaloes. Proteomic characterization using two-dimensional gel electrophoresis (2DE) found 93 differentially expressed proteins between old and young buffalo meat. Proteome analysis using 2DE revealed 191 and 95 differentially expressed protein spots after 6 days of ageing in young and old buffalo meat, respectively. The matrix assisted laser desorption ionization time-of flight/time-of flight mass spectrometry (MALDI-TOF/TOF MS) analysis of selected gel spots helped in identifying molecular markers of tenderness mainly consisting of structural proteins. Protein biomarkers identified in the present study have the potential to differentiate meat from young and old buffaloes and pave the way for optimizing strategies for improved buffalo meat quality.


Subject(s)
Aging/physiology , Buffaloes/metabolism , Food Quality , Meat/analysis , Muscle, Skeletal/chemistry , Muscle, Skeletal/ultrastructure , Proteome/analysis , Animals , Buffaloes/anatomy & histology , Electrophoresis, Gel, Two-Dimensional , Meat/standards , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/metabolism , Proteomics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 145: 239-244, 2015 Jun 15.
Article in English | MEDLINE | ID: mdl-25791880

ABSTRACT

Silver/tungsten oxide multi-layer films are deposited over quartz substrates by RF magnetron sputtering technique and the films are annealed at temperatures 200, 400 and 600°C. The effect of thermal annealing on the phase evolution of silver tungstate phase in Ag/WO3 films is studied extensively using techniques like X-ray diffraction, micro-Raman analysis, atomic force microscopy and photoluminescence studies. The XRD pattern of the as-deposited film shows only the peaks of cubic phase of silver. The film annealed at 200°C shows the presence of XRD peaks corresponding to orthorhombic phase of Ag2WO4 and peaks corresponding to cubic phase of silver with reduced intensity. It is found that, as annealing temperature increases, the volume fraction of Ag decreases and that of Ag2WO4 phase increases and becomes highest at a temperature of 400°C. When the temperature increases beyond 400°C, the volume fraction of Ag2WO4 decreases, due to its decomposition into silver and oxygen deficient phase Ag2W4O13. The micro-Raman spectra of the annealed films show the characteristic bands of tungstate phase which is in agreement with XRD analysis. The surface morphology of the films studied by atomic force microscopy reveals that the particle size and r.m.s roughness are highest for the sample annealed at 400°C. In the photoluminescence study, the films with silver tungstate phase show an emission peak in blue region centered around the wavelength 441 nm (excitation wavelength 256 nm).


Subject(s)
Oxides/chemistry , Silver/chemistry , Temperature , Tungsten Compounds/chemistry , Tungsten/chemistry , Luminescence , Microscopy, Atomic Force , Spectrum Analysis, Raman , X-Ray Diffraction
10.
J Clin Diagn Res ; 8(7): PC10-3, 2014 Jul.
Article in English | MEDLINE | ID: mdl-25177612

ABSTRACT

BACKGROUND: Neonatal hypoglycemia is the most common carbohydrate metabolic disturbance seen in case of neonates and especially in preterm neonates. Accurate and rapid determination of hypoglycemia and its prompt treatment is of utmost importance to decrease morbidity and mortality of neonates. AIMS: To estimate blood glucose in neonates and test the efficacy of HemoCue Glucose 201+ analyser and B Braun Glucometer by comparing with centralised laboratory testing. To compare the blood glucose in capillary and venous blood samples of neonates. SETTINGS AND DESIGN: Hospital setting; Comparative Study Materials and Methods: After obtaining informed consent, all neonates admitted to Neonatal Intensive Care Unit (NICU) were screened for blood sugar. Capillary and venous blood glucose was estimated employing HemoCue Glucose 201+ analyser and B Braun Glucometer. Simultaneously, the same venous sample was collected in fluoride tube and sent to central clinical biochemistry laboratory for glucose estimation. When anaemia or polycythemia was clinically suspected the same venous sample was sent for estimation of Hematocrit (Hct). STATISTICAL ANALYSIS: Comparison of blood glucose concentration of B Braun glucometer, HemoCue Glucose 201+ analyser and centralis/ed plasma glucose levels was done by using students test. All the statistical analysis were done using software SPSS 6 version. RESULTS: Mean values of blood glucose (100.2 + 48.4) with B Braun glucometer was significantly higher (p=0.003) when compared to plasma glucose values (76.95 + 45.99) estimated in central laboratory and HemoCue glucose 201+ analyser (82.9 + 51.4). HemoCue glucose 201+ analyser did not show significant difference (p=0.463) with central laboratory testing. There was no significant difference between the capillary and venous sample estimated in both the instruments. Estimation with HemoCue glucose 201+ analyser correlated well with central laboratory testing in neonates with blood glucose <55mg/dl, CONCLUSION: We conclude that HemoCue glucose 201+ analyser appears to be a suitable point of care (POC) blood glucose measurement device in neonates on both capillary and venous blood samples, as it showed a good correlation with central laboratory values without significant interference from Hct.

11.
J Indian Med Assoc ; 109(5): 351-2, 2011 May.
Article in English | MEDLINE | ID: mdl-22187776

ABSTRACT

Parasitic conjoined twins are rare variations of abnormal conjoined twinning. A case of asymmetric conjoined twins is presented in which the incomplete parasite was attached to the sacrococcygeal region of the normal twin (autosite). The parasitic twin had a rudimentary bony hemipelvis, both lower limbs with gross deformities of right lower limb covered with intact skin, intergluteal fold without anal orifice, partial gastro-intestinal system and a rudimentary bladder. The parasitic twin was excised on the third day of life and the normal twin was discharged. Postnatal follow-up after one month showed a healthy infant with normal growth pattern.


Subject(s)
Twins, Conjoined/pathology , Female , Humans , Infant, Newborn , Pregnancy , Twins, Conjoined/surgery , Young Adult
12.
Natl Med J India ; 24(2): 86-7, 2011.
Article in English | MEDLINE | ID: mdl-21668051

ABSTRACT

Classic Bartter syndrome, depending on the severity, presents during childhood or adolescence as failure to thrive and may be incorrectly labelled as protein-energy malnutrition, particularly in children from a low socioeconomic stratum. We encountered a 5-year-old boy who was asymptomatic till the age of 3 years. Despite adequate dietary intake, he was admitted and managed in various hospitals as a case of protein-energy malnutrition. On evaluation, he had unusual features in the form of persistent hypokalaemia and polyuria leading us to suspect a renal tubular disorder. Treatment of the condition resulted in good weight gain and normalization of serum electrolytes.


Subject(s)
Bartter Syndrome/complications , Bartter Syndrome/diagnosis , Failure to Thrive/diagnosis , Failure to Thrive/etiology , Protein-Energy Malnutrition/diagnosis , Child, Preschool , Diagnosis, Differential , Humans , Hypokalemia/diagnosis , Hypokalemia/etiology , Male , Polyuria/diagnosis , Polyuria/etiology
13.
Indian J Hematol Blood Transfus ; 27(2): 107-10, 2011 Jun.
Article in English | MEDLINE | ID: mdl-22654303

ABSTRACT

Mixed autoimmune haemolytic anemia (AIHA) is defined by the presence of both warm and cold auto antibodies. Diagnosis is based on detection of autoantibodies by monospecific direct antiglobulin test showing a pattern of IgG and complement C3d and presence of cold agglutinins. We report a rare case of primary mixed AIHA in a 12 year old girl who responded to corticosteroids.

14.
Rheumatol Int ; 31(8): 1081-4, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20340020

ABSTRACT

Various surgical procedures including percutaneous and open release and arthroscopic procedures have been described to treat recalcitrant tennis elbow. We present the outcome of Boyd-McLeod surgical procedure for tennis elbow resistant to non-operative treatment in twenty-seven patients (twenty-nine limbs). Boyd McLeod procedure involves excision of the proximal portion of the annular ligament, release of the origin of the extensor muscles, excision of the bursa if present, and excision of the synovial fringe. The average time interval from the onset of symptoms of tennis elbow until surgery was 28 months (range 8-72 months). Of those patients, 91% reported complete relief of symptoms with return to full normal activities including sports. Average post-operative time for return to professional/recreational activity was 5 weeks. One case developed pain secondary to ectopic bone formation after surgery, which settled after excision, and in another there was no pain relief with Boyd McLeod procedure. Two patients had scar tenderness that did not affect the final outcome. We conclude that Boyd-McLeod procedure is an effective treatment option in patients with resistant lateral epicondylitis.


Subject(s)
Arthroscopy , Debridement/methods , Elbow Joint/surgery , Tendons/surgery , Tennis Elbow/surgery , Adult , Aged , Female , Humans , Male , Middle Aged , Postoperative Complications , Recovery of Function , Tennis Elbow/pathology , Tennis Elbow/physiopathology , Treatment Outcome
15.
Curr Rev Musculoskelet Med ; 2(1): 51-5, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19468918

ABSTRACT

Coracoid impingement syndrome is a less common cause of shoulder pain. Symptoms are presumed to occur when the subscapularis tendon impinges between the coracoid and lesser tuberosity of the humerus. Coracoid impingement should be included in the differential diagnosis when evaluating a patient with activity-related anterior shoulder pain. It is not thought to be as common as subacromial impingement, and the possibility of the coexistence of the two conditions must be taken into consideration before treatment of either as an isolated process. If nonoperative treatment fails to relieve symptoms, surgical decompression can be offered as an option.

16.
J Phys Condens Matter ; 21(32): 325501, 2009 Aug 12.
Article in English | MEDLINE | ID: mdl-21693969

ABSTRACT

We present here the structural, electronic structure, magnetic and Mössbauer studies of NdFe(1-x)Ni(x)O(3) (0≤x≤0.3) samples. All the samples exhibit a single-phase orthorhombic structure with space group Pbnm. The near-edge x-ray absorption fine structure (NEXAFS) studies reveal that, with the Ni substitution at Fe sites, a new spectral feature about 1.5 eV lower than the pre-edge structure of NdFeO(3) in the O K edge is observed due to the 3d contraction effect and is growing monotonically with the increase of Ni concentration. The Fe L(3,2), Ni L(3,2) and Nd M(5,4) edges confirm the trivalent state of Fe, Ni and Nd ions. The Mössbauer spectra fitted with two Zeeman sextets confirm the different surroundings of Ni around Fe ions. With the increase in Ni concentration, the sextets are broadened. The increase of quadrupole splitting and the decrease of the hyperfine field suggest the change in the ordered regime of the system. The magnetic behaviour at low temperatures is explained in the context of competition among moments of rare earth (Nd) and transition metal ions (Fe/Ni). The strong paramagnetic contribution of the Nd magnetic sublattice and spin flip phenomenon is observed from the temperature dependence of zero-field-cooled and field-cooled magnetization where spin crossover is observed. The isothermal hysteresis loops show a decrease of magnetization and increase of coercivity with the increase in temperature and complements magnetization versus temperature. The results are explained on the basis of the spin reorientation phenomenon.

17.
J Nanosci Nanotechnol ; 8(8): 4135-40, 2008 Aug.
Article in English | MEDLINE | ID: mdl-19049190

ABSTRACT

Cobalt ferrite thin films have been deposited on fused quartz substrates by pulsed laser deposition at various substrate temperatures, T(s) (25 degrees C, 300 degrees C, 550 degrees C and 750 degrees C). Single phase, nanocrystalline, spinel cobalt ferrite formation is confirmed by X-ray diffraction (XRD) for T(s) > or = 300 degrees C. Conventional XRD studies reveal strong (111) texturing in the as deposited films with T(s) > or = 550 degrees C. Bulk texture measurements using X-ray orientation distribution function confirmed (111) preferred orientation in the films with T(s) > or = 550 degrees C. Grain size (13-16 nm for T(s) > or = 300 degrees C) estimation using grazing incidence X-ray line broadening analysis shows insignificant grain growth with increasing T(s), which is in good agreement with grain size data obtained from transmission electron microscopy.

18.
J Phys Condens Matter ; 20(23): 235214, 2008 Jun 11.
Article in English | MEDLINE | ID: mdl-21694305

ABSTRACT

We present here a detailed investigation of the static and dynamic magnetic behavior of a Mg(0.95)Mn(0.05)Fe(2)O(4) spinel ferrite nanoparticle system synthesized by high-energy ball milling of almost identical particle size distributions ([Formula: see text], 5.1 and 6.0 ± 0.6 nm). The samples were characterized by using x-ray diffraction, Mössbauer spectroscopy, dc magnetization and frequency dependent real χ(')(T) and imaginary χ('')(T) parts of ac susceptibility measurements. The zero-field-cooled (ZFC) and field-cooled (FC) magnetization have been recorded in a low field and show a behavior typical of superparamagnetic particles above a temperature of 185 ± 5 K, which is further supported from the temperature dependent Mössbauer measurements. The fact that the blocking temperature calculated from the ZFC magnetization and Mössbauer data are almost similar gives a clear indication of the interparticle interactions among these nanoparticle systems. This is further supported from the FC magnetization curves, which are almost flat below a certain temperature (less than the blocking temperature), as compared with the monotonically increasing behavior characteristics of non-interacting superparamagnetic particles. A shift of the blocking temperature with increasing frequency was observed in the real χ(')(T) and imaginary χ('')(T) parts of the ac susceptibility measurements. The analysis of the results shows that the data fit well with the Vogel-Fulcher law, whereas trials using the Neel-Brown and power law are unproductive. The role of magnetic interparticle interactions on the magnetic behavior, namely superparamagnetic relaxation time and magnetic anisotropy, are discussed.

19.
Indian J Orthop ; 42(1): 100-1, 2008 Jan.
Article in English | MEDLINE | ID: mdl-19823666

ABSTRACT

A 24-year-old male presented with an inability to walk after a trivial fall. He had pain and mild swelling anterior to the right knee for the past one year. X-ray showed a transverse fracture of patella with a lytic lesion occupying most of the two halves of the patella. Fine needle aspiration cytology (FNAC) of the lytic lesion revealed a few osteoclastic giant cells and occasional osteoblasts against a hemorrhagic background. Patellectomy was performed. Histology revealed trabecular bone admixed with proliferating chondroid tissue at places admixed with myxoid and fibrous tissue with focal areas of calcification suggestive of chondroblastoma. Focal areas showed osteoclastic giant cells with areas of hemorrhage. The purpose is to present a rare tumor occurring at an unusual site which presented as pathological fracture.

20.
J Nanosci Nanotechnol ; 7(6): 2081-6, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17654996

ABSTRACT

Structural, magnetic, and electronic properties of Ti/Ni multilayer (ML) samples as a function of Ti layer thickness are studied and reported in this paper. For this purpose [Ti (t nm)/Ni (5 nm)] x 10 ML samples, where t = 3, 5, and 7 nm have been deposited by using electron beam evaporation technique under UHV conditions at room temperature. Structure of ML samples were determined by using XRD (X-ray diffraction) technique and observed that Titanium is deposited mainly in amorphous nature with FCC structure at lower Ti layer thickness of 3 nm, which transform to crystalline HCP structures above than this Ti layer thickness. Corresponding fitted GIXRR (grazing incidence X-ray reflectivity) patterns shows asymmetric nature of Ti-Ni and Ni-Ti interfaces because of heavy intermixing and interdiffusion of Ni and Ti atoms at Ti-Ni interfaces at lower Ti layer thickness. The depth profiling core level and valence band measurements carried out by using XPS (X-ray photoelectron spectroscopy) technique confirms the interdiffusion and intermixing leading to Ti-Ni alloy phase formation at interfaces during deposition, particularly at lower Ti layer thickness of 3 nm. The corresponding magnetization behavior of ML samples has been investigated using Magneto-Optical Kerr Effect (MOKE) technique and observed that, coercitivity decreases while saturation magnetization increases with Ti layer thickness variations. These results are interpreted and discussed in terms of observed micro-structural changes due to Ti layer thickness vitiations in Ti/Ni multilayer samples.


Subject(s)
Crystallization/methods , Magnetics , Membranes, Artificial , Nanostructures/chemistry , Nanostructures/ultrastructure , Nickel/chemistry , Titanium/chemistry , Light , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Nanotechnology/methods , Particle Size , Photometry , Scattering, Radiation , Surface Properties
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