Titania Particles Research Articles

Study of Combustion of Titanium Particles Aimed at Generation of TiO2 Nanoparticles

Study of Combustion of Titanium Particles Aimed at Generation of TiO2 Nanoparticles

Inflammatory Gene Profile and Particle Presence in Peri-Implant Mucosa: a Pilot Study on 9 Patients.

The purpose of this pilot study is to compare gene expression in mucosa around dental implants with zirconia abutment to titanium and investigate presence of particles in mucosa samples and on implant heads. Ten patients with a single implant supported prosthesis connected to zirconia or titanium abutments were invited at the five-year control. A clinical examination and a survey on experience of function and appearance were conducted. A mucosa biopsy taken in close vicinity to the implant were analysed by real-time polymerase chain reaction (qPCR) and presence of particles in a scanning electron microscope/energy-dispersive X-ray spectroscope (SEM/EDX). Cytological smear samples were collected and analysed through inductively coupled plasma mass spectrometry (ICP-MS) to investigate presence of particles on implant heads. In total, 9 patients participated in the study, five with titanium abutments and four with zirconia abutments. All patients were satisfied with function and aesthetics. Titanium and iron particles were detected in mucosa biopsies. The ICP - MS analysis demonstrated presence of zirconia and titanium. Several proinflammatory genes were upregulated in the zirconia abutment group. Around zirconia abutments a slight increase in proinflammatory response and amount of wear particles was seen as compared to titanium. Wear particles of titanium were present in all soft tissue samples, however zirconia particles only in the samples from implants heads/mucosa with zirconia abutments.

B-160 Quantification of Titanium using Inductively Coupled Plasma Mass Spectrometry ICP-MS to Monitor Toxic Levels in Blood

Abstract Background When titanium is used as a metallic implant, it can potentially cause toxicity to humans due to wear of the implant. As the implant wears, small particles of titanium and other metals may be released into the surrounding tissue. These particles can cause an immune response, leading to adverse reactions such as allergies and implant-associated infections. Additionally, the wear of the implant can also lead to the release of metallic ions, which can have toxic effects on surrounding tissue and cells. Workers may be exposed in factories that use the metal in the manufacture of paints, varnishes, ceramics, plastics, rubber, soldering rods, floor coatings, food dyes, industrial textiles, cosmetics, glass products, pharmaceuticals, manufacturing of rubber tires and in the production of electronic components. This highlights the importance of regular monitoring and maintenance of titanium prostheses to minimize the wear and toxicity as well as monitoring commonly exposed professionals. The aim of the study was to validate a reliable method for quantification of titanium in blood. Methods Validation was performed using an Inductively Coupled Plasma Mass Spectrometry, 7850 ICP-MS. Analytical specificity is ensured using single particle analysis with fragmented ions that are exclusive to Ti, quantifier ion 47 Da. The procedure involves a small amount of 125 µL of blood, followed by dilution with 100 µL of internal standard at concentration of 1.0 µg/L more 2.275 µL of diluent containing 1-Butanol, Ammonium Hydroxide, EDTA and Triton X-100. After that, samples are submitted to hydrolysis to 37 °C for 40 min. The internal standard was purchased from Agilent at a concentration of 10.0 µg/mL. Finalizing the preparation samples are followed by aspiration into the SPS 4 model injector. Quantitation is achieved by the comparison of the responses from a given sample with the responses of calibrators with known concentrations prepared through Multi Element Cabibration at concentration of 10.0 µg/mL of Ti. Linearity was observed in the expected concentration range from 2.0 to 7.0 µg/L and blood samples were evaluated at six different concentrations and six times each at the same time of the study. Diluent was used as a biological matrix for the study and the standard acquired was Agilent. Results The linearity coefficient of determination (R) was 0.9998. The method showed 100% selectivity and no residual effect interference that was evaluated in blood matrix. To determine the average inter-assay CV%, three different concentrations were analyzed over three days and the results for each low, medium, and high concentration level were 4.27%, 4.22% and 3.33%, respectively. The accuracy of the method was cheeked by analyzing samples of known concentration and expressed as a percentage. A time total analysis was 3.5 min. Conclusion The method was efficient for the determination of titanium in blood. The efficiency and selectivity promoted by the ICP-MS technique, combined with the reliable preparation method, can be used in the diagnosis of wear in metallic titanium prostheses and occupational exposure.

Caffeic acid phenethyl ester ameliorates titanium particle-induced bone loss and inflammatory reaction in a mouse acute model

With the increasing clinical application of dental and orthopedic implants, the problem of peri-implant osteolysis has attracted attention. The inflammatory response and osteoclast differentiation induced by wear particles play an important role in peri-implant bone loss. However, the treatment of peri-implant osteolysis is still lacking. In the present study, we investigated the effect of caffeic acid phenethyl ester (CAPE) on titanium particles induced bone loss in a mouse model. We found that CAPE significantly suppressed titanium particle-induced bone loss in vivo. CAPE treatment decreased ratio of nuclear factor kappa B receptor activator ligand (RANKL)/osteoprotegerin (OPG) and subsequently reduced osteoclastogenesis in the mouse model. In addition, CAPE downregulated the expression and secretion of interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) stimulated by titanium particles in vivo. In summary, we conclude that CAPE prevent the titanium particles-induced bone loss.

Nanoparticles Titanium Dioxide with Thymus vulgaris extract in preservation and prolong the shelf life of cheese

Cheese is considered a perishable food that is affected by microorganisms, and due to the properties of nanomaterials that have antimicrobial activity, they have been used synergistically with plant extracts in inhibiting the action of microorganisms that cause cheese spoilage. In this study, TiO2 (Titanium dioxide) nanoparticles were synthesized using Thymus vulgaris leaves extract (TVLE) . Atomic Force Microscopywas used to investigate Titanium dioxide/ TVLE nanoparticles characterize, which improved the regular spherical shape and granular distribution of nanoparticles with a particle size of 13 nm . The results showed that the minimum inhibitory concentration (MIC) of Titanium dioxide was at a concentration of 4 mg/ml and 80 mg/ml for TVLE, while it was 2 + 20 mg /ml for Titanium dioxide and TVLE .The inhibitory effect increased against Brucella melitensis recorded 12 mm when mixing Titanium dioxide and TVLE, compared with the inhibitory effect of Titanium dioxide, which recorded 10.5 mm and TVLE, with an inhibition diameter 8.1 mm. The effect of using titanium particles and thyme leaves’ extract was studied alone at a concentration of 4 mg/ml and 80 mg/ml and also when mixed in the microbial properties and pH of white soft cheese samples, which were prepared in the laboratory and contaminated with Brucella melitensis at refrigerated storage conditions (5Cº) for 21days. The effect of the synergism relationship between TiO2 / TVLE significantly reduced the total number of microorganisms in samples contaminated and uncontaminated with B. melitensis. Adding titanium dioxide and TVLE at concentrations of 4 and 80 mg/ml contributed significantly to maintaining the pH level during the storage period compared with the control group.

Ball-milling of titanium dioxide and zinc oxide for enhanced UV protection

Among various sunscreen materials, zinc oxide and titanium dioxide are excellent physical sunscreen components; however, these two materials tend to aggregate and form micrometer-sized particles that may impact their performance. This study utilizes fine grinding techniques to break up the aggregated oxide particles into small nanoparticles with a narrow size distribution averaging around 200 nm in diameter. The ground zinc oxide and titanium dioxide particles exhibit enhanced ability in absorbing and scattering ultraviolet radiation compared to their original state before grinding. Consequently, this research offers innovative concepts as well as approaches towards developing highly efficient yet low-toxic physical sunscreen components while significantly contributing to the preparation process optimization for mixed material performance.

Tribo-corrosion and titanium particles: A conducive factor for implant complication

In dentistry, titanium and its alloys are utilized for implants due to their unique blend of chemical, physical, and biological properties. These alloys are employed in both cast and wrought forms. The fractures of the alloy-abutment interface, abutment, or implant body are caused by the long-term presence of corrosion reaction products and ongoing corrosion. Implant failure results from the combined effects of stress, corrosion, and bacteria.

Raman imaging to identify microplastics released from toothbrushes: algorithms and particle analysis

Microplastics are small plastic fragments that are of increasing concern due to their potential impacts on the environment and human health. The source of microplastics is not completely clear and might originate in daily lives such as from toothbrushes. When toothbrushes are used to clean teeth, small plastic debris and fragments can be potentially released into mouths directly or environment indirectly. This study aims to examine the release of microplastics from toothbrushes, using Raman imaging to identify and visualise the plastic debris with an increased signal-noise ratio via hyper-spectrum analysis. Using algorithms to convert the hyper-spectrum to an image, the plastic can be distinguished from the co-formulated titanium oxide particles that are not uniformly distributed along the plastics. The non-uniform distribution can lead to the bias results if a single spectrum analysis is conducted at one position rather than imaging analysis to scan an area. The potential false image originating from the off-focal position for the confocal Raman is overcome using the terrain map to guide the Raman imaging. The imaging analysis balancing between the low magnification to capture the overview and the high magnification to test the details is also discussed. While the release amount of microplastics from the toothbrush is estimated at thousands daily with the expected variation, the results of this study have confirmed the release of microplastics in daily lives. The imaging analysis approach along with algorithm can help to identify the chemical elements of microplastics from the complex background, which can benefit the further research on microplastics towards risk assessment and remediation.

Characterisation and quantification of titanium dioxide nanoparticles in food simulants by single particle inductively coupled plasma-tandem mass spectrometry using a high efficiency sample introduction system

This article reports the development of a novel method based on single particle inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) using a high efficiency sample introduction system (HESIS) for the characterisation and quantification of titanium dioxide (nano)particles (TiO2 NPs) in food simulants. The use of the mass-shift mode (O2 + H2 as a mixture reaction gas) avoids the isobaric interferences of 48Ca isotope hence allowing accurate characterisation of TiO2 NPs in complex matrices such the foodstuffs. Two HESIS (APEX™ Q and APEX™ Ω) were compared with the conventional ICP-MS/MS sample introduction system in terms of sensitivity and trueness for the detection of TiO2 NPs in various (organic) food simulants. APEX™ Ω proved to be an excellent approach to avoid matrix effects from food simulants and provided significantly lower limits of detection in size (LODsize) compared to the conventional introduction system. In order to avoid the saturation of the detector when detecting large TiO2 particles (> 300 nm), the analyses were carried out using the forced analogue detection mode and accurate characterisation of TiO2 NPs in terms of size and concentration was achieved, with an average LODsize of 20 nm over 3 days. This confirms the feasibility of this novel approach using an APEX™ Ω for the characterisation and quantification of TiO2 NPs in complex matrices such as the food simulants and its application to real-life studies regarding the migration of TiO2 NPs from food containers into the simulants.

P24-38: EFSA Made a Manifest Error on the Safety of Titanium Dioxide (E171) Particles as a Food Additive for Humans

P24-38: EFSA Made a Manifest Error on the Safety of Titanium Dioxide (E171) Particles as a Food Additive for Humans

Oxygen content effect on mechanical properties and microstructure of TZM alloy

A series of molybdenum‑titanium‑zirconium (TZM) alloys with continuous oxygen content gradients were fabricated by powder metallurgy and the correlation between microstructure and properties was investigated. By controlling the carbon source, TZM-like alloys with an oxygen content of 2000 ppm, 1000 ppm, and TZM alloy with an oxygen content of 300 ppm (±100) were obtained, followed by rolling and heat treatment, and the effect of oxygen on the development of the microstructure and the mechanical properties of the alloy was studied. The results show that the changing of the oxygen content has a significant impact on the mechanical properties and microstructure of the alloy. With the increase in oxygen content, titanium and zirconium are more inclined to combine with oxygen to form oxide particles of titanium and zirconium (TiO2, ZrO2), the secondary phase particles increase significantly, and the alloy strengthening mode changes from solid solution strengthening to secondary phase dispersion strengthening. Owing to the inhibition of grain boundary migration by the secondary phase, the grain size of the alloy decreases as its oxygen content rises, which causes an increase in hardness of around 10 HV0.1 for every 1000 ppm increase in oxygen content. According to the Hall-Petch relationship, the yield strength of the annealed alloy increased from 336 MPa (300 ppm) to 556 MPa (2000 ppm) with smaller grain size. Kernal Average Misorientation (KAM) is used to characterize the dislocation density of the alloy, and the results show that the value of KAM is negatively correlated with the toughness of the alloy. The KAM value of the alloy is the lowest at 1000 ppm and its greatest elongation reaching 16.8%. Dislocation cells formed in the long-striped grains with an oxygen content of 300 ppm, greatly enhancing the strength of the material and maintain good plasticity. TZM alloy with 300 ppm oxygen has the highest tensile strength of 866 MPa and has an elongation of 15%, which is the leading performance compared with ASTM-specification B386/B386M.

Structural Macrokinetics of Combustion of Ti-Based Mixtures with Titanium Particles of Different Sizes

Structural Macrokinetics of Combustion of Ti-Based Mixtures with Titanium Particles of Different Sizes

(Invited) True Particle-Size Dependence of Photocatalytic Activity of Octahedral-Shaped Anatase Titania

Here, attempts to prepare octahedral-shaped anatase titanium(IV) oxide (titania) particles (OAPs) of uniform bulk structure (anatase with negligible non-crystalline components), surface structure (only exposing {101} facets) and particle size are reported as the first and sole example of a "pure" metal-oxide powder. The OAP samples were prepared by sonication-hydrothermal (HT) reaction of potassium-titanate nanowires through the process modified from the previous report [1]. Characterization of the samples by Rietveld analysis of XRD patterns (including non-crystalline phases using an internal standard) [2], reversed double-beam photoacoustic spectroscopy (RDB-PAS; a method measuring energy-resolved distribution of electron traps mainly located on the surface of metal-oxide and the other semiconducting samples) [3,4] and SEM observations revealed the homogeneousness of crystalline bulk, surface and particle size, respectively, to indicate the samples "pure". By controlling the preparation conditions, several OAP samples with different average size ranging of ca. 60–260 nm keeping the purity of the OAP shape. Roughly speaking, the particle-size distribution of those samples was the size of ca. 80% particles in the range of +20% of the average. Photocatalytic activities of those samples in (a) methanol dehydrogenation with in-situ deposited platinum to yield hydrogen, (b) oxidative decomposition of acetic acid under aerobic conditions to yield carbon dioxide and (c) oxygen evolution from deaerated aqueous silver sulfate were examined under ultraviolet-light (> 290 nm) irradiation to find that there seemed no particle-size dependence for the systems (a) hydrogen evolution and (b) carbon-dioxide evolution, while the activity in system (c) to liberate oxygen was almost linearly increased with the particle size [5]. These particle-size dependences of photocatalytic activity seem strange but could be "true" considering the purity of those samples, i.e., almost pure bulk crystal component exposing only anatase{101} facets. The previously reported particle-size dependence might be incorrectly derived due to the unknown effects by the other structural parameters.[1] Molecules 19, 19573 (2014). [2] Catal. Today 313, 218 (2018). [3] Chem. Commun. 52, 12096 (2016). [4] Electrochim. Acta 264, 83 (2018). [5] To be submitted.

Investigation on Mechanical and Machinability Properties of Aluminium Metal Matrix Composite Reinforced with Titanium Oxide (TiO2) and Graphite (Gr) Particles

This research paper deals with the preparation process and testing of metal matrix composites comprising Aluminium alloy (Al 6061) as the base metal and Titanium oxide (TiO2) and Graphite (Gr) as reinforcements. Due to their high specific strength, superior malleability, lightweight, stiffness and excellent resistance to corrosion, oxidation and wear, the aluminium metal matrix composites are preferred in the automobile and industrial sectors for component manufacturing. No work reported on machinability properties of Titanium oxide (TiO2) and Graphite (Gr) reinforced aluminium composites so far. This study prepared and studied samples composed of variable proportions of titanium oxide and graphite. The samples were prepared using the stir casting method. While stirring, the required additives were added to the molten aluminium mixture. To perform the tests, the samples were prepared according to standard dimensions after solidification. The mechanical properties of the prepared composite were examined using various test procedures, such as strength and hardness. Scanning electron microscopy was used to examine the microstructure of the test composite samples. The EDAX test confirmed the presence of graphite and Titanium oxide in the aluminium based composite specimens. Furthermore, machining was done to study the cutting forces on the tool. The test results showed a significant impact of the reinforced materials on the mechanical and machinability properties of aluminium metal matrix composites. Gr decreases hardness, while TiO2 increases it. TiO2 and Gr reinforcements increase the tensile strength of Al 6061 composites. The addition of TiO2 decreased the composite's elongation. The proof strength of 2 % Al6061 was high, however it decreased with 3 % Gr and increased with TiO2 reinforcement. Reinforcements increase cutting forces during machining; when comparing the machining of Al 6061 to that of 3 % Gr and 5 % TiO2, a 50 % increase in cutting forces is noticed. However, excessive reinforcements may reduce cutting forces due to poor matrix-reinforcement adhesion. HIGHLIGHTS The mechanical and machinability properties of aluminium metal metrics reinforced with Titanium oxide (TiO2) and graphite (Gr) have not been reported so far in the literature. In this study, aluminium based composites reinforced with variable proportions of titanium oxide and graphite were prepared and studied. The fabrication process was done by stir casting by adding the required additives into the molten mixture of aluminium, followed by continuous stirring. The solidified samples were cut according to the standard dimensions and various test procedures were conducted to examine the mechanical and machinability properties of the prepared composites. Gr reduces hardness, whereas TiO2 enhances it. TiO2 and Gr reinforcements boost Al 6061 composite tensile strength. TiO2 addition reduced elongation of the composite. 2 % proof strength of Al 6061 was strong, however it dropped with 3 % Gr and rose with TiO2 reinforcement. Reinforcements results higher cutting forces while machining, however excessive supplements lower cutting forces may be due to poor matrix-reinforcement bonding. GRAPHICAL ABSTRACT

Synthesis of Ti-Ni and Zr-Ni Core–Shell Particles Using Galvanic Replacement

This article focuses on the galvanic replacement synthesis of Ti-Ni and Zr-Ni metal systems with a “core-shell” structure, which are potential precursors for intermetallics. The authors defined effective synthesis parameters and formation features of polymetallic systems characterized by granulometric, phase, and elemental composition. X-ray fluorescence and X-ray phase analysis methods showed that the deposition of nickel on dispersed titanium and zirconium leads to the production of test samples with phase composition representing a mechanical mixture of Ni and Ti, and Ni and Zr. The method of X-ray fluorescence analysis showed that the presence of hydrofluoric acid with a 0.5-1.5 M concentration results in the formation of fixed quantitative ratios of elements in the precipitate, which allows the quantitative composition of dispersed systems “titanium-nickel” and “zirconium-nickel” to be regulated within a relatively wide range. Scanning electron microscopy proved that all synthesized systems are characterized by a highly porous structure that follows the titanium and zirconium particle surface contour and the presence of spherical nanoscale subunits on the formed particle surface.

The development of Au-titania photoanode composites toward semiflexible dye-sensitized solar cells

Considering the widespread use of windows in modern urban landscapes, converting these substrates into photovoltaic devices would remarkably impact modern energy generation. A flexible dye-sensitized solar cell (DSSC) architecture is preferred for such applications. A key component of the DSSC is the dye-sensitized photoanode. Herein, we examine different nanoparticle composites within the semiconductor anode formulation and their effect on device performance. Mesoporous titania particles (TiO2) modified with Au-nanoparticles (TiO2@AuNPs) were synthesized using precipitation strategies to assess the solvent effect on the particle size and the efficiency of the devices. The materials were then fully characterized through SEM, XRD, and DRS before and after thermal treatment. A paste prepared from the synthesized semiconductors was applied onto the substrate using the doctor blading technique. The use of high thermal treatment for glass substrates (HTT), low-temperature thermal treatment (LTT), and LTT combined with 2 h of UV curing (LTT_UV) was explored. In the case of ITO/PET (flexible substrate) only low temperature thermal treatment were used (LTT and LTT_UV). After characterization (XRD and DRS), the anodes were loaded using a metal-free dye. To complete the comparison, several groups of cells were characterized: considering solvent (EtOH and EtOH:H2O), thermal treatment (HTT, LTT, and LTT_UV), and semiconductor material (TiO2 and TiO2@AuNP). Rigid (glass anode-glass cathode) and semiflexible (flexible anode-glass cathode) DSSCs were obtained with efficiencies from 0.03% to 2.4%, with a substantial performance difference seen using different thermal treatments, and a mild to low effect on semiconductor composition and the used substrate.

Recycling ABS from WEEE with Peroxo-Modified Surface of Titanium Dioxide Particles: Alteration on Antistatic and Degradation Properties

Recycling ABS from WEEE with Peroxo-Modified Surface of Titanium Dioxide Particles: Alteration on Antistatic and Degradation Properties

Experimental Wear Analysis of Nano-Sized Titania Particles as Additives in Automotive Lubricants

This study focuses on the wear effects of nano-sized titania as a potential engine lubricant additive. Titanium dioxide nanoparticles have promising wear-reducing properties and significant tribological potential. In this article, titania nanoparticles were homogenized in Group III automotive oil at five different concentrations (0.1; 0.2 … 0.5 wt%). The nanodoped oil samples were tested on a linear oscillating tribometer with oil circulation. Based on the tribological results, titania nanoparticles increased friction by 20–32% but can reduce the wear area by up to 32%. According to the confocal microscopic examination, wear volume can be reduced by up to 57% with titania nanoparticles. Titania nanoparticles improved the repeatability of tribological measurements. A scanning electron microscopy examination of the wear track revealed that the characteristic wear of the tribological system was abrasive, but a significant amount of adhesive wear was also observed. Energy dispersive X-ray spectroscopy analysis found that the nanoparticles fill the deeper trenches of the wear. The worn surface uniformly contains TiO2 particles and the quantified normalized titanium concentration was between 0.56 and 0.62%.

Elucidation of solid particle interfacial Phenomena in liquid sodium: Magnetic interactions on liquid metal and solid atoms at the solid interface

We were able to detect the nuclear magnetic resonance (NMR) signal of a liquid sodium clinging to the interface of solid metal particles for the first time. In this study, we confirmed the difference in the relaxation times due to the difference in the interactions between liquid sodium and metal particles suspended in the liquid sodium. It was found that the surface of the micro titanium particles and liquid metallic sodium interact physically, not chemically.

Tribochemically Controlled Atom Transfer Radical Polymerization Enabled by Contact Electrification.

Traditional mechanochemically controlled reversible-deactivation radical polymerization (RDRP) utilizes ultrasound or ball milling to regenerate activators, which induce side reactions because of the high-energy and high-frequency stimuli. Here, we propose a facile approach for tribochemically controlled atom transfer radical polymerization (tribo-ATRP) that relies on contact-electro-catalysis (CEC) between titanium oxide (TiO2 ) particles and CuBr2 /tris(2-pyridylmethylamine (TPMA), without any high-energy input. Under the friction induced by stirring, the TiO2 particles are electrified, continuously reducing CuBr2 /TPMA into CuBr/TPMA, thereby conversing alkyl halides into active radicals to start ATRP. In addition, the effect of friction on the reaction was elucidated by theoretical simulation. The results indicated that increasing the frequency could reduce the energy barrier for the electron transfer from TiO2 particles to CuBr2 /TPMA. In this study, the design of tribo-ATRP was successfully achieved, enabling CEC (ca. 10 Hz) access to a variety of polymers with predetermined molecular weights, low dispersity, and high chain-end fidelity.