Ppm Of Ti Research Articles

Simultaneous separation and determination of Ti and Fe in uranium alloy by ion chromatography

A simple and reliable ion chromatographic (IC) method for the simultaneous separation and quantification of Ti and Fe in U-Ti alloys is proposed. The developed method does not require pre-separation of matrix uranium and hence direct injection of the dissolved sample into IC is feasible. Separation was realized on a reversed phase column dynamically modified with ion interaction reagent (IIR). Suitability of three IIRs was evaluated and Camphor-10-sulphonic acid (CSA) was selected. Separation of Ti and Fe was achieved by mandelic acid whereas the strongly retained U(VI) was eluted with tartaric acid. The developed method was calibrated for Ti and Fe in presence of U(VI). The limit of detection (LOD) for Ti and Fe is 0.2 µg/mL and 0.02 µg/mL, respectively. The precision of measurements was better than 5 % (RSD) at 1 ppm of Ti and 0.2 ppm of Fe. The real samples were analysed with the developed method.

Fretting corrosion testing of acetabular modular tapers for total hip replacements: A comparison of two designs.

Acetabular components (DePuy Pinnacle (A) and Stryker Trident (B), Ti-6Al-4V shellsand CoCrMo liners) with varying geometries were assembled under a 4 kN seating load. Liner-displacement was recorded. Cyclic compression to 4 kN, R = 0.01, 9 Hz was applied for three million cycles to evaluate fretting corrosion currents (n = 5). Fretting currents, load-displacement, ion dissolution, and disassembly loads were used to compare device performance. Data were analyzed using ANOVA with Tukey post hoc comparisons (p < 0.05). Liner seating displacements were not significantly different between groups. Fretting currents averaged over the initial 10 h and over three million cycles were 0.17 μA (A) and 0.55 μA (B) and 0.05 μA (A) and 0.17 μA (B), respectively(p = 0.19). No variation in ion averages between A and B (0.23and 0.45 ppm for Ti [p = 0.21], 0.63and 0.85 ppm for Co [p = 0.47]) existed. Average push-out forces, -2.41(A) and -2.42 kN (B), were not significantly different (p = 0.97). SEM and EDS showed some titanium and metal oxide transfer from the shell to the liner in both designs. Overall, both implant designs exhibited very minor MACC in these experiments. This study demonstrates quantitative measures of in vitro fretting corrosion over the course of threemillion cycles and the minimal degree of acetabular taper damage. Clinical Significance: Retrieval studies show dual mobility acetabular shell-liner tapers with metal-on-metal contacts are susceptible to fretting corrosion in vivo.

Methodology for the characterisation of characteristic spectral profiles, applied to chromium Kβ

The investigation of tests of quantum electrodynamics in the X‐ray regime down to 2–20 parts per million (ppm) amplifies the need for improved characterisation of asymmetric reference sources and energies in this regime. While several transition metal characteristic energies have been defined, most are not referenced to accurate profiles or robust links to the metre via X‐ray optical interferometry. Lower intensity Kβ transitions have relatively poor accuracy – we ask how to determine Kβ transitions to an accuracy approaching those of Kα transitions. Instrumental broadening normally encountered in X‐ray experiments shifts the features of profiles used for calibration, such as peak energy, by a significant amount many times the quoted accuracies. We present a study of a methodology used recently to determine energies and profiles experimentally down to 4.5 and 2.7 ppm for Ti and V Kβ. In this study, we investigate the robustness of the methodology for a difficult data set and demonstrate that the approaches to and characterisation of the chromium Kβ spectral profile are consistent with accurate measurements in the literature down to 24 ppm. The peak energy of the chromium Kβ spectral profile is found to be 5946.68(14) eV prior to instrumental broadening. Characterisation of the spectral profile of the radiation, including the instrumental broadening, allows us to obtain an accurate and notably transferable standard. Significantly, we present a widely applicable methodology for achieving and using this standard. This approach has been used down to an accuracy of 2–5 ppm.

Improved electron probe microanalysis of trace elements in quartz

Quartz occurs in a wide range of geologic environments throughout the Earth's crust. The concentration and distribution of trace elements in quartz provide information such as temperature and other physical conditions of fomation. Trace element analySes with modern electron-probe microanalysis (EPMA) instruments can achieve 99% confidence detection of - 100 ppm with fairly minimal effort for many elements in samples of low to moderate aVerage atomic number such as mauy common oxides and silicates. HoweVer, trace element measurements below 100 ppm in many materials are limited, not ouly by the precision of the background measurement, but also by the accuracy with which background levels are determined. A new correction algorithm has been developed and tested on both Cameca and JEOL instruments, which applies a quantitative correction to the emitted X-ray intensities duriug the iteration of the sample matrix correction based on a zero level (or known trace) abundance calibration standard. This iterated blank correction, when combined with improved background fit models, and an aggregate'' intensity calculation utilizing multiple spectrometer intensities in software for greater geometric efficiency, yields a detection limit of 2 to 3 ppm for Ti and 6 to 7 ppm for AI in quartz at 99% t-test confidence with similar levels for absolute accuracy.

Applicability of MiniPal 4 compact EDXRF spectrometer for soil and sediment analysis

AbstractOptimum measurement parameters for analysis of soil and sediment samples with the compact MiniPal 4 (MP4)EDXRF spectrometer (PANalytical, Almelo, The Netherlands) were presented. The following elements were considered: K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As and Pb. Since the elements from low Z to medium Z region were covered, three measurement conditions (sequences) were defined. The following parameters were selected for measurement of the elements K, Ti, and V: voltage = 12 kV; current = 750 µA; filter material: Al_thin. Cr, Mn and Fe were measured at 20 kV; 300 µA with Al filter while for measurements of Ni, Cu, Zn, As, Pb, Rb, and Sr an Ag filter was selected and tube voltage and current were 30 kV and 300 µA. Each sequence was measured for 200 s and measurements were done in the air. MP4 spectrometer was characterized with acceptable precision, long‐term stability and satisfactory minimum detection limit for the analyses of soil and sediment materials. For the elements K, Mn, Fe, and Ti the precision of the analysis was better than 0.5% and for all the other elements better than 5%. Detection limits for sediment samples were 20 ppm for K, 6.1 ppm for Ti, 5.2 for Mn, 4 ppm for Fe, 4.2 ppm for As and less than 2 ppm for all the other elements. These values were significantly lower compared to typical concentrations of the same elements found in unpolluted soil and sediments. Copyright © 2008 John Wiley &amp; Sons, Ltd.

Consequences of Silicon Segregation on the Dielectric Properties of Sintered Alumina

The dielectric breakdown strengths of two series of sintered alumina samples of low and high impurity content (where Si is the dominant element with, respectively, 90 and 1500 ppm) and impurity level (25 ppm of Si and 12 ppm of Ti) are compared with positron lifetime measurements. The dielectric breakdown strength of sintered alumina is found higher than that of single crystal. This improvement is stronger when silicon is the only major foreign element. If, in addition to SiO2, MgO and CaO are present in substantial amounts, the improvement is lessened. This is attributed to the enhanced bulk solubility of Si. These results are discussed by calling for the potential traps for positrons and electrons that are located at grain boundaries. It is deduced that the improvement of the dielectric breakdown strength stems from the consequences of Si segregation at grain boundaries via electron trapping in shallow traps, which are likely the x '' Al • Al ) V : (3Si clusters.

Influence of titanium ion on mineral formation and properties of osteoid nodules in rat calvaria cultures

The effect of the addition of titanium ion (Ti) on osteoblast function and the mineralization of osteoid nodules in rat calvaria cultures was characterized. Concentrations of 10 ppm of Ti or more inhibited cell proliferation; 5 ppm or less either had no effect or stimulated proliferation. The number of nodules formed was not influenced by 5 ppm of Ti, but mineral deposition in nodules was suppressed, as revealed by von Kossa staining. Likewise, 5 ppm of Ti inhibited the incorporation of [45Ca] in cultures during nodule formation even if the Ti was withdrawn from the medium when mineralization was initiated. In order to test whether the synthesis of osteoid components was affected, the expression of osteonectin (OSN), osteopontin (OPN), osteocalcin (OSC), and alkaline phosphatase (ALP) mRNAs as well as ALP enzyme activity was analyzed. The expression of OSN and OPN mRNAs was reduced dramatically, but OSC mRNA was little affected by 5 ppm of Ti. Ti delayed the development of ALP mRNA expression and enzyme activity relative to the controls. Thus Ti treatment changed the proportional composition of cellular mRNA contributing the osteoblast phenotype. © 1999 John Wiley & Sons, Inc. J Biomed Mater Res, 47, 220–227, 1999.

Influence of titanium ion on mineral formation and properties of osteoid nodules in rat calvaria cultures.

The effect of the addition of titanium ion (Ti) on osteoblast function and the mineralization of osteoid nodules in rat calvaria cultures was characterized. Concentrations of 10 ppm of Ti or more inhibited cell proliferation; 5 ppm or less either had no effect or stimulated proliferation. The number of nodules formed was not influenced by 5 ppm of Ti, but mineral deposition in nodules was suppressed, as revealed by von Kossa staining. Likewise, 5 ppm of Ti inhibited the incorporation of [(45)Ca] in cultures during nodule formation even if the Ti was withdrawn from the medium when mineralization was initiated. In order to test whether the synthesis of osteoid components was affected, the expression of osteonectin (OSN), osteopontin (OPN), osteocalcin (OSC), and alkaline phosphatase (ALP) mRNAs as well as ALP enzyme activity was analyzed. The expression of OSN and OPN mRNAs was reduced dramatically, but OSC mRNA was little affected by 5 ppm of Ti. Ti delayed the development of ALP mRNA expression and enzyme activity relative to the controls. Thus Ti treatment changed the proportional composition of cellular mRNA contributing the osteoblast phenotype.

Use of proton-induced X-ray emission (PIXE) analysis in the evaluation of large volume parenteral rubber stoppers

The use of external beam proton-induced X-ray emission (PIXE) analysis for determining the elemental composition of three different types of rubber stoppers used to seal parenteral solutions is described. The stoppers were immersed in 0.9% sodium chloride solution in conical flasks. The flasks were then autoclaved in a pilot autoclave using an F o value of 15 min at 121°C. The PIXE measurements were performed at the 2.5 MeV Van de Graaff accelerator in the University of Helsinki. The results show that the PIXE method clearly revealed the differences between different types of rubber stoppers. The elements found were, e.g., Fe, Ti, Zn, Br. The limits of detection were 2 ppm for Ti, 6 ppm for Fe, 2 ppm for Cu, 1 ppm for Zn, 3 ppm for Br and 0.5 ppm for Pb. The concentrations of a certain element vary greatly from sample to sample, for example, that of Zn by a factor of 4000. The elemental compositions of 4482 PH 4001/45 and 4782 PH 4106/50 are nearly identical, whereas the elemental composition of 4443 PH 21/50 is more complicated. Heavy elements were either non-existent or present in very low quantities. PIXE analysis is useful for detecting and quantifying elements with atomic numbers greater than 12. A particular feature of the method is that many elements can be analyzed simultaneously if a detection system with sufficient resolution is available. The sensitivity of the method at the ppm level and the fact that analyses may be performed on samples of small size make it a promising technique for analyzing the chemical composition of rubber stoppers. This method could be used in various pharmaceutical applications, since analysis can be performed under a normal atmosphere without requiring the use of a vacuum.

Titanium Determination under High-Sensitivity Conditions with 2-(5-Chloro-2-pyridylazo)-5-dimethylaminophenol. I

Abstract The optimum working conditions for the complexing reactions between Ti(IV) and 2-(5-chloro-2-pyridylazo)-5-dimethylaminophenol (5.ClDMPAP) in aqueous alcoholic solutions were studied. When an ethanol solution of 5.ClDMPAP is added to a Ti(IV) aqueous solution, complex species, whose spectral and stoichiometric characteristics depend on pH, develop rapidly. The complex selected for the analytical work forms between pH 4.7 and 5.8 and has a 3:1 ligand-metal molar ratio. The complex fulfils Beer’s law up to a Ti(IV) concentration of 0.7 ppm, working at λmax=580 nm. The optimum concentration range (Ringbom) was between 0.05 and 0.7 ppm of Ti(IV). The molar absorptivity at λmax=580 nm and Sandell index are 4.39×104 dm3 mol−1 cm−1 and 0.0011 μg cm−2, respectively. An absorptiometric method to determine Ti(IV) was developed and the proper ways to reduce interferences produced by some anions and cations are described. The method developed was applied to Ti(IV) determination in optical glass and ceramic materials.

Spectrophotometric Determination of Ti(IV) With 2‐Benzylideniminobenzohydroxamic Acid

AbstractA new method for the photometric determination of Ti(IV) with 2‐benzylideniminobenzohydroxamic acid is described with 50% ethanol and 0.5 M HCl medium, the complex shows an absorption maximum at 392 nm. The molar absorptivity value is 5.110 1.mol−1 cm−1 an it is possible determine between 2.0 and 6.0 ppm of Ti(IV). The method is applied to determination of Ti(IV) in a pharmaceutical drug.