Traces Of Titanium Research Articles

Effect of Friction Machining on Low Carbon Steel with Titanium Traces in terms of Surface Hardening

Effect of Friction Machining on Low Carbon Steel with Titanium Traces in terms of Surface Hardening

Photocatalytic degradation of MB by TiO2: studies on recycle and reuse of photocatalyst and treated water for seed germination.

Photocatalysis is an effective way for treatment of wastewater and degradation of dyes. It is important to assess the reusability of photocatalyst and treated water after the treatment process. In this study, the photocatalytic activity of TiO2 (titanium dioxide) and TiO2-TMAOH (titanium dioxide-tetramethylammonium hydroxide) was analyzed for degradation of methylene blue dye. Enhanced degradation of methylene blue is observed while treated with TiO2-TMAOH with photodegradation efficiency (PDE) 80% within 20 min. A further study shows the reusability of TiO2 for degradation of dye for six cycles with a decrease in photodegradation efficiency from 90% (cycle-1) to 50% (cycle-2). Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and cyclic voltammetry (CV) analysis were carried out to identify the functional groups in treated water, traces of titanium, and TMAOH, respectively. Seed germination of Vigna radiata using TiO2- and TiO2-TMAOH-treated water shows equivalent and consistent growth. Water quality analysis of treated water shows improved biochemical oxygen demand (BOD) level (1.5 mg L-1), which is suitable for reusability of water for many applications. The outcomes suggest treated water can be used for irrigation and plantation purposes.

Impact of Paleosalinity, Paleoredox, Paleoproductivity/Preservation on the Organic Matter Enrichment in Black Shales from Triassic Turbidites of Semanggol Basin, Peninsular Malaysia

Turbidite-associated black shale of the Semanggol Formation is extensively distributed in the northwestern part of the Western Belt, Peninsular Malaysia. The black shale occurs as a dark grey to black and thick to medium-bedded deposit. It represents the distal part of submarine fan system (outer-fan) overlying interbedded sandstone to shale facies of the mid-fan and conglomeratic pebbly sandstone facies of the inner-fan. Field observations and its widespread occurrence have resulted in the black shale being considered as a potential analog for a source rock in offshore Peninsular Malaysia. The present study includes detailed mineralogical (XRD, SEM, and EDX analysis), inorganic geochemical (major oxides, trace elements TEs, and rare earth elements REEs), and Rock-Eval pyrolysis analyses of the black shale samples, collected from the Gunung Semanggol, Bukit Merah, and Nami areas in northwestern Peninsular Malaysia. The primary focus of this study is to investigate the provenance, paleoredox conditions, paleoclimate, sedimentary rate, paleoproductivity, and upwelling system that would be helpful to understanding the role of these parameters in the enrichment of organic matter (OM) in the black shale. The Rock-Eval analysis shows that the black shale of the Semanggol Formation comprises type-III kerogens, which suggests organic input from a terrestrial source. The black shale also contains mature to postmature organic matter. Based on the mineralogical analysis, the mineral composition of the black shale comprises illite and kaolinite, with abundant traces of quartz and feldspar as well as few traces of titanium and zircon. Inorganic geochemical data designate black shale deposition in a passive margin setting that has experienced moderate to strong weathering, semi-arid to hot arid climate, and moderate sedimentation rate. Ratios of Ni/Co, U/Th, and V/(V+Ni) along with slightly negative to positive Ce* anomalies and UEF-MoEF cross-plot unanimously indicate anoxic/dysoxic water conditions that are suitable for organic matter preservation. Geochemical proxies related to modern upwelling settings (i.e., Cd/Mo, Co vs. Mn) show that the deep marine black shale was strongly influenced by persistent upwelling, a first-order controlling factor for organic matter enrichment in the distal part (outer fan of the submarine fan system) of the Semanggol Basin. However, productivity-controlled upwelling and a high sedimentary rate, as well as high-productivity in oxygen-depleted settings without strong anoxic conditions, has played an essential role in the accumulation of organic matter.

High-efficiency thermoluminescent detectors for measuring the absorbed ionizing radiation dose in the environment

A study has been conducted with the goal of comparing the characteristics of TLD-K detectors based on sodium silicate ceramics to the characteristics of monocrystalline lithium fluoride detectors that contain traces of titanium and magnesium (TLD-100), as well as anion-defected aluminum oxide (TLD-500), which are widely used in thermoluminescent dosimetry. Because they are soil-equivalent, SiO2 detectors are well suited for measuring the absorbed radiation dose in soils. The results of the comparison indicate that TLD-K detectors are preferable to LiF detectors in environmental applications due to the better uniformity of the detector sensitivity in a batch, the wider range of measurable doses, and the lower threshold in determining small doses.

Exfoliative Cytology and Titanium Dental Implants: A Pilot Study

Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri-implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri-implant oral mucosa around titanium dental implants. The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri-implantitis. Cytologic samples of the peri-implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma-mass spectrophotometry. Metal-like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri-implant mucosa of both patients with and without peri-implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri-implantitis group compared with the group without peri-implantitis; no traces of titanium were observed in controls. Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri-implant mucosa.

Microscopical and microbiologic characterization of customized titanium abutments after different cleaning procedures.

To assess and characterize pollution micro-particles and bacterial growth on customized titanium abutments after steaming, ultrasonic and plasma cleaning treatments. Thirty commercially available implant abutments, after customization, were randomly divided into 3 groups of 10 and cleansed by steam (considered as control group), ultrasonic cleaning (test group 1) and plasma of Argon (test group 2). For all specimens, SEM analysis and EDAX microanalysis were performed to count and characterize pollution micro-particles, both on the abutment surface and implant-abutment connection. For the control and test groups, mean values and standard deviations were calculated for number and density of micro-particles. Statistical differences were determined by one-way ANOVA with Scheffe multiple comparison test. The level of statistical significance was set at P≤0.05. Additional microbiologic analysis was performed to detect bacterial contamination on the abutment surface. In the control group, the number of micro-particles on average was 117.5, and 14.1, respectively, on the abutment surface and connection. In the test groups, no pollution was revealed on the abutment (average of 1.09 and 1.13 spots, respectively, in test group 1 and test group 2) and connection (1.28 and 1.41, respectively, in test group 1 and test group 2). The analysis of variance (ANOVA) showed a statistically significant difference for all the variables examined. For each variable, at least one of the groups differs from the others. Scheffe multiple comparison test showed that all comparisons for every variables between the control group and both groups are significant, while there were some comparisons between test group 1 and test group 2 that were not significant. EDAX microanalysis identified micro-particles as residual of lubricant mixed with traces of Titanium and other metals. Microbiologic analysis demonstrated the presence of bacterial growth on the abutment surface only in the control group (111.5±11.43CFU/ml/implant-abutment as mean value). In the test groups, absence of growing microorganisms was found. This study confirmed that both plasma and ultrasonic treatments can be beneficially adopted for abutment cleaning process after laboratory technical stages, to supposedly favor soft tissue healing and implant-prosthetic connection stability.

Obtaining the Ni-TiC composite powder by the carbidization of titanium nickelide

The goal of this study is to investigate the mechanism and kinetics of carbidization of the titanium nickelide powder, which allows one to obtain the Ni-TiC composite powder. It is established by experimental methods and theoretical analysis that, in the temperature range 1000–1200°C, this process proceeds in the internal mode with the decomposition of NiTi and with the formation of a nickel-based solid solution with dispersed titanium carbide particles distributed in it. It is shown that, with the carbon excess in the starting charge, the final product consists of a nickel matrix, including ∼3 at % carbon and traces of titanium, and particles of almost stoichiometric titanium carbide. With the deficiency of carbon in the starting charge, the Ni matrix contains ∼1.1 × 10−2 at % carbon and >0.65 at % titanium, while the particles of titanium carbide have the composition TiC0.5-TiC0.8. The suggested model of this process allows one to evaluate the time that the NiTi particles completely decompose and qualitatively describe the time dependence of the particle size of titanium carbide.

Characterization of materials eliciting foreign body reaction in stapled human gastrointestinal anastomoses

Staples are made of titanium, which elicits minimal tissue reaction. The authors have encountered foreign body reaction associated with stapled human gastrointestinal anastomoses, although the literature has no reports of this. The aim of this study was to identify the refractile foreign materials causing this reaction. Histological sections were taken from 14 gastrointestinal specimens from patients with a history of a stapled anastomosis within the specimen excised. These were reviewed by light and polarization microscopy. Scanning electron microscopy and energy dispersive X-ray analysis were carried out on these sections, staples and stapler cartridges used for gastrointestinal surgery. Foreign bodies rich in fluorine were found in three patients, and those rich in carbon in 12. Other elements identified included oxygen, calcium, sodium, potassium, magnesium, aluminium and silicon. One specimen was found to contain titanium with no surrounding foreign body reaction. Stapler cartridges contained carbon, oxygen, fluorine, calcium, sodium, potassium, magnesium, aluminium, silicon and traces of titanium. Staples were composed of pure titanium with some fibrous material on the surface containing elements found in stapler cartridges. The presence of foreign body reaction was confirmed in stapled human gastrointestinal anastomoses. The source of refractile materials eliciting this reaction was the stapler cartridges.

A retrieval study on morphological and chemical changes of titanium osteosynthesis plates and adjacent tissues

To examine (a) morphological and chemical changes of retrieved titanium osteosynthesis plates, (b) findings in adjacent soft tissues during plate removal and to evaluate possible correlations among the above-mentioned issues. Ninety-four osteosynthesis plates were retrieved, of which 60 were studied and evaluated (including the adjacent soft tissue) in more details, 4-36 months following osteosynthesis in 26 trauma cases, 12 orthognathic and 6 maxillofacial reconstructive cases. Selected clinical parameters during plate removal, were studied. Specialized laboratory methods including light and electron microscopy as well as spectrometry and X-ray microanalysis were used to analyse the retrieved material. Plates showed major mechanical changes (scratches, scraping and deformation) without corrosion. Soft tissue inflammation-mainly mild and chronic-was found in 53 of 94 plates removed, a statistically significant percentage. Pigmented deposits in the soft tissues manifested only traces of titanium when analysed elementally. There was no statistically significant correlation between the laboratory findings of plates and tissues, or between plate morphology and clinical findings recorded. According to the findings of this study, inflammation in tissues adjacent to osteosynthesis plates should not be attributed to mechanical changes in the plates. Pigmented tissue deposits were neither found to be titanium to the extent previously reported, nor were they correlated with tissue inflammation. These findings lead to the assumption that titanium plates do not have to be removed to avoid local inflammatory problems.

Detachment of titanium and fluorohydroxyapatite particles in unloaded endosseous implants

The shape, surface composition and morphology of orthopaedic and endosseous dental titanium implants are key factors to achieve post-surgical and long-term mechanical stability and enhance implant osteointegration. In this study a comparison was made between 12 titanium screws, plasma-spray-coated with titanium powders (TPS), and 12 screws with an additional coating of fluorohydroxyapatite (FHA-Ti). Screws were implanted in the femoral and tibial diaphyses of two mongrel sheep and removed with peri-implant tissues 12 weeks after surgery. The vibrational spectroscopic, ultrastructural and morphological analyses showed good osteointegration for both types of implants in host cortical bone. The portion of the FHA-Ti implants in contact with the medullary canal showed a wider area of newly formed peri-implant bone than that of the TPS implants. Morphological and EDAX analyses demonstrated the presence of small titanium debris in the bone medullary spaces near the TPS surface, presumably due to the friction between the host bone and the implant during insertion. Few traces of titanium were detected around FHA-Ti implants, even if smaller FHA debris were present. The present findings suggest that the FHA coating may act as a barrier against the detachment of titanium debris stored in the medullary spaces near the implant surface.

Influence on the Long‐Term Stability of Polysilicon Resistors from Traces of Titanium and Tungsten

Trace amounts of a residue, formed during patterning of the TiW film by etching in , cause a significant improvement in the long‐term stability of polysilicon integrated circuit resistors. The stabilization is the result of a reduction in the amount of hydrogen reaching the grain boundary dangling bonds during processing. This appears to be due to a retardation in the diffusion of hydrogen caused by an ability of the TiW residue on the borophosphosilicate glass surface to change the relative amounts of atomic and molecular hydrogen. The amounts of hydrogen involved in the resistivity changes have been evaluated. Typically, for 500 nm thick boron‐implanted chemical vapor deposited polysilicon films with a grain size of 150 nm, the concentration of grain boundary traps was . The amount of hydrogen passivating dangling bonds after hydrogen annealing and plasma‐enhanced chemical vapor deposition nitride passivation was . After a 1000 h electrical and thermal stress at 150°C saturated the resistance drift, the amount of hydrogen that left the dangling bonds was . The presence of TiW residue reduced the amount of hydrogen reaching the dangling bond by and that leaving after stressing by . © 2000 The Electrochemical Society. All rights reserved.

Nuclear microanalysis of titanium

Application of charged particle activation analysis (CPAA) for the detection of traces of titanium has been demonstrated. Experimental samples containing traces of titanium varying from ppm to ppb levels were prepared by coprecipitating it with aluminium hydroxide, subsequently converted to Al2O3. Titanium in Al2O3 were irradiated with 40 MeV α-particles in the Variable Energy Cyclotron, Calcutta. The element was detected through the product radioisotopes,48V,47Ca,47Sc,51Cr,49Cr and48Cr, produced from various nuclear reactions such as (α, pxn), (α, xn), etc. Suitability of Al2O3 as diluent matrix for the element has been verified.

NON ISATIS SED VITRUM OR, THE COLOUR OF LINDOW MAN

Summary. As part of the examination of the fragments of a further human body recovered from Lindow Bog, Cheshire, samples of skin were examined using electron probe X‐ray micro‐analysis. The ionic composition showed an excess of aluminium, silica and copper, with traces of titanium and zinc. These are interpreted as the residues of clay‐based copper and other pigments applied to the body. The literary evidence of the use of body paint amongst the Britons is reviewed in the light of these analyses and the interpretation of Classical references in terms of woad‐painted Britons is questioned.

Spectrophotometric Determination of Calcium and Magnesium in Pure Alumina with P&R and EBT after Selective Extraction of the Matrix with Tri-n-butyl Phosphate

A spectrophotometric method for the determination of calcium and magnesium in pure alumina has been developed. The method involves extraction of aluminium with tri-n-butyl phosphate (TBP) at pH ∼ 4.3. Magnesium and calcium are then determined in aqueous solution at pH ∼ 7.80 and at pH ∼ 12 using eriochrome black T (EBT) and P&R as metallochromic indicators at 540 and 560 nm respectively. The method obeys Beer's law from 0.2 to 3.0 μg MgO/ml and 0.2 to 4.0 μg CaO/ml respectively. Traces of titanium (if present) are effectively masked with triethanol amine (TEA), but traces of iron (if present) are extracted with aluminium. The interferences of Co, Ni, Cu and Mn can be avoided by masking with KCN. The method has been applied to synthetic and various pure alumina samples.

Differential-pulse polarographic determination of traces of titanium in solar grade silicon

The proposed method for the determination of Ti in solar grade silicon is based on the catalytic activity of titanium(IV) in presence of chlorate ions. In acidic oxalate solution containing chlorate, titanium(IV) gives an exceptionally high polarographic current owing to its catalysed electroreduction and the well-shaped polarographic wave is suitable for trace analysis.

Separation of trace amounts of titanium by the sorption of the titanium peroxocomplex on silica gel

The possibility of the analytical use of the sorption of titanium peroxocomplex on silica gel for the determination of trace amounts of titanium was studied. The exchange capacity of silica gel in dependence on the time and the composition of the titanium peroxocomplex sorbed were described. A simple and very efficient separation procedure has been developed for the determination of traces of titanium in various waters and water-soluble salts.

Combined anion-exchange separation and spectrophotometric determination of traces of titanium in sea water

Traces of titanium in sea water have been preconcentrated by anion-exchange from acidified samples in the presence of thiocyanate. Titanium adsorbs strongly on a column of Amberlite CG 400 (SCN−) and can be stripped easily by elution with 2 M hydrochloric acid — 1.5% hydrogen peroxide solution. Titanium in the effluent is determined spectrophotometrically with diantipyrylmethane as colour reagent. The combined method allows to determine traces of titanium very selectively and sensitively in sea water as well as non-saline water on a 41 sample basis. The method yields a coefficient of variation of 7% at a titanium level of ∼0.4 μg per l.

Determination of Ti, V, Zn and W traces by proton activation analysis

Procedures are described for determining traces of titanium in scandium, vanadium in titanium, zinc in copper and tungsten in tantalum, utilizing activation with 11 Me V protons. Experimental data on48V,51Cr,66Ga and182Re yields and analytical sensitivities are reported.

Distribution of Concretions from Selected Soils of the Inner Bluegrass Region of Kentucky

AbstractTotal iron and manganese was determined on concretions and soil samples by X‐ray emission. Soils studied included Maury, Mercer, and Lawrence, which are well‐drained, moderately well‐drained and somewhat poorly‐drained, respectively. Iron‐Manganese concretions were observed in all horizons, with a maximum of 46% by weight in a Maury C horizon. The Fe/Mn ratios decreased with increasing concretion size. This decrease was largely due to increased Mn content associated with the larger size concretions. Further analyses for composition showed that quartz and clay minerals (vermiculite, montmorillonite, kaolinite, and mica) account for most of the remaining fractions. Traces of titanium and phosphorus were also found. Microscopic studies of the concretions indicated two types of internal fabric; (i) undifferentiated (structureless), and (ii) differentiated or concentric structure. Concretions from the somewhat poorly drained soils are characterized by undifferentiated fabric and diffuse external boundaries. In contrast the concretions from the well‐drained soils are usually spherical, with sharp external boundaries and differentiated fabric.

THE NATURE OF POLYMERIZATION CATALYSTS PREPARED FROM METAL ALKYLS AND TITANIUM HALIDES

A study has been made of the composition and structure of the insoluble complexes formed in the reaction of aluminum triisobutyl or lithium n-butyl with titanium tetrachloride or trichloride in heptane at room temperature by chemical and X-ray diffraction analyses. For the tetrachloride systems it has been shown that, with metal alkyl:titanium tetrachloride ratios of 0.5 to 4, at least 50% of the titanium is present in the tetravalent state and that there is considerable loss of chlorine and alkyl groups. The aluminum complexes are amorphous except at component ratios of 0.5 to 1, where the X-ray pattern indicated traces of titanium trichloride.With the aluminum triisobutyl–titanium trichloride system, X-ray evidence has shown that the titanium trichloride remains essentially unchanged. This result, together with the low aluminum content (less than 0.5%), is consistent with Natta's suggestion that this catalyst for define polymerization consists of a trichloride surface on which small quantities of aluminum alkyl are chemisorbed.The reaction between lithium butyl and titanium trichloride at ratios above unity results in the formation of a new crystalline compound having a sodium chloride type lattice with a lattice spacing of 5.20 Å. The compound is thought to be a double salt of the type (LiCl)n.TiCl2 or (LiCl)n.TiCl. Evidence of a second crystalline component was also noted but it could not be identified.Tentative reaction schemes are proposed for the formation of the various complexes and their structures are considered in relation to their ability to polymerize 1-butene.