Titanate Content Research Articles

Composite based on Poly(ethylene-co-vinyl acetate) with lead-titanate for gamma attenuation

The radioprotective ability of composite materials based on a poly (ethylene-co-vinyl acetate) matrix with dispersed lead titanate filler has been estimated. The filler was obtained from the environmentally friendly synthesis based on exchanging potassium ions for lead in potassium titanates. The gamma ray protective composites have low density, good mechanical qualities and are able to be reprocessed by high-performance extrusion or injection molding techniques. The present work is dedicated to assess mechanical and gamma ray shielding properties of poly (ethylene-vinyl acetate) composites with different lead titanate content (70, 80 and 90 wt percent of lead titanate). The study was carried out for the emission of 137Cs, 60Co and 241Am isotopes with energies 0.6617 MeV, 1.332/1.173 MeV and 0.0595 MeV respectively. The study of radiation-protective properties showed that for 137Cs radiation half value layer for the composite containing 90 wt% of lead titanate is three times higher than for neat lead: 2.1 and 0.7 cm respectively. For the 60Co emission, these values are more close: 1.9 cm for 90 wt% composite and 1.2 cm for lead. The layer of 0.5 cm of composite with 70 % lead titanate almost fully diminishes the low-energetic 241Am radiation, and hence, is superior to lead foil of the same length. Mass attenuation coefficients of 70% composite for 0.6617 MeV, 1.332/1.173 MeV and 0.0595 MeV are 0.088, 0.046 and 2.487 cm2/g respectively. The tensile elongation at fracture decrease is 460% for 70/30 lead titanate/poly (ethylene-vinyl acetate) and is equal to 6% for 90/10 lead titanate/poly (ethylene-vinyl acetate).

Impact of friction stir welding parameters and Al2TiO5 reinforcement on the mechanical, wear, and corrosion performance of dissimilar welded aluminium composite joints

This study investigates the impact of friction stir welding (FSW) parameters on dissimilar AA5052-Al2TiO5/AA6061-Al2TiO5 composite joints. Tool rotational speed (TRS), feed rate, and aluminum titanate (Al2TiO5) content are varied, and their influence on microstructure, mechanical properties, wear resistance, and corrosion behavior is assessed. Joints fabricated with 1200 rpm TRS, 40 mm/min feed rate, and 2 wt% Al2TiO5 exhibit the highest tensile strength (170.11 MPa) due to grain refinement in the stir zone (SZ). Joints with 3 wt% Al2TiO5 have near-base composite hardness (86.12 HV) and exhibit distinct microstructures across different zones. Samples with superior mechanical properties display finer grains in the SZ, while other zones exhibit elongated grains. The sample reinforced with 3 wt% Al2TiO5 (W9) demonstrates enhanced wear resistance attributed to its high hardness. Additionally, the sample fabricated with 1200 rpm TRS, 40 mm/min feed rate, and 2 wt% Al2TiO5 (W15) displays the lowest corrosion rate (0.44 mpy) due to its fine structure. Fracture analysis reveals different failure mechanisms in tensile and wear testing.

Influence of ultrasonic treatment and heating/cooling under electric field on high-k cellulose-barium titanate composites

The present research reports the ultrasonic assisted synthesis of ferroelectric cellulose-barium titanate composites (C/BT). As proved by wide angle X-ray diffraction (WAXD) and by scanning electronic microscopy (SEM), the composites consist of perovskite-type barium titanate particles (BT) of 400- 600 nm, disposed around the cellulose microfibers. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and wide angle X-ray diffraction (WAXD) revealed the modifications of structure/morphologies of the prepared sample as compared to pristine cellulose, with direct consequences on the polymer crystalline domains, on the uniformity of BT dispersion and on the dielectric properties of the composites. The composites obtained by ultrasonic treatment possess high dielectric constants (58.6-140.5), better breakdown strengths (8.9-17.7 kV/mm) and energy storage densities (2.6-9.0 J/cm3) as compared to BT particles, as well as very low dielectric losses (0.27-3 x 10-4) at industrial frequencies (50-55 Hz), the values being dependent on the content of barium titanate and on the preparation parameters.

Properties of ferroelectric composites in the microwave range

Ferroelectric ceramics of barium titanate and its solid solutions have found wide applications in technology, while compositions of a binary system with strontium titanate are most in demand. Electrically controlled components based on the barium titanate – strontium titanate ferroelectric ceramics are widely used in accelerator technology and the use of these materials is relevant at the present time. In the microwave range, composites based on the solid solution system barium titanate – strontium titanate ВаxSr1–xTiO3 (BST). Ferroelectric samples based on ВаxSrx–1TiO3 compound, where x = 0; 0.1; 0.3; 0.5; 0.7 were obtained using a conventional ceramic technology. The temperature dependences of the electrical properties of bulk ceramic samples based on ferroelectric composites were received in the temperature range 100°C to 350°C at a frequency of 1 kHz. It has been established that dielectric parameters significantly depend on the BaTiO3 content in BST compositions. To carry out a research in the frequency range from 0.1 to 8.5 GHz, an experimental setup was manufactured for measuring the electrical properties of ferroelectric materials based on an Agilent E5071C vector analyzer and a microstrip line. To conduct temperature studies, a microstrip line with a controlled sample was placed in a heat, cold and moisture chamber of the Bench-Top SU-261 series, in which it has been heated up to 60°C. The amplitude-frequency characteristics of the transmission coefficient (S21) of samples when heated from 20 °C to 60°C with an interval of 10 degrees were studied. The resonant frequency and quality factor of the resonator have been determined from the amplitude-frequency characteristic. Based on the value of the resonant frequency and the geometric dimensions of the sample, the dielectric constant of the sample material was calculated. It has been shown that with increasing barium titanate content (x = 0.1–0.3), the dielectric constant of the samples under study increases, and the resonant frequency shifts to lower frequencies. For samples with a barium titanate content of 50% and higher (x≥0.5), there are no resonance dependences and strong absorption of electromagnetic waves is observed. It has been established that with increasing temperature, the resonant frequency of composite material samples shifts to higher frequencies. Frequency dispersion of the dielectric constant is observed, which indicates the relaxor properties of the ceramic samples under study. Experimental investigations were carried out using a microwave strip line, a coaxial measuring cell and a capacitive converter; this made it possible to measure the dielectric constant of materials with values of more than several hundred in the microwave range and significantly reduce the control time when conducting thermal studies. It was shown that with a change in temperature, the electrophysical properties of the samples change significantly, which can be used in various systems and devices to change the reflection coefficient and phase of the electromagnetic wave.

Chelated titanate modified multilayer graphene-butylpyridine latex/polyethylene terephthalate composites with enhanced thermal conductivity

The low thermal conductivity of polyethylene terephthalate (PET) fabric, which affects the thermal conducting between different layers in composites, is often the weakness in the application of thick butadiene-vinylpyridine latex (BVL)/PET composite, slowing down the composites' processing efficiency and dissipation of frictional heat during operation. In this study, chelated titanate modified multilayer graphene (CTMMG) was used to functionalize butadiene-vinylpyridine latex (CTMMG-BVL), which was further applied for preparing composite to improve the thermal conductivity of PET-reinforced composite (CTMMG-BVL/PET). The static and dynamic stabilities of the CTMMG dispersion as well as thermal conductivity and electrostatic properties of the CTMMG-BVL film and CTMMG-BVL/PET composite were investigated. It was found that both static and dynamic stabilities of the CTMMG dispersion within 24 h were superior to unmodified multilayer graphene (MG) as the MG content and mass ratio of titanate to MG were 10 mg/mL and 25 %, respectively. Compared to the BVL film, the thermal conductivity and tensile strength of CTMMG-BVL film (CTMMG content: 2.19 wt%) were increased by 28.8 % and 4.5 %, respectively. The thermal conductivity of the CTMMG-BVL/PET composite was further enhanced by 48.3 % (from 2.65 to 3.93 W/(m·K)) compared to that of BVL/PET. The electrostatic property of the CTMMG-BVL film and CTMMG-BVL/PET composite was significantly improved. Fourier transform infrared (FTIR) analysis indicated that the mechanism for the excellent static and dynamic stability of waterborne CTMMG dispersions was attributed to the synergistic effects of the hydrogen bond and chemical bond formed between titanate and MG. The prepared CTMMG-BVL/PET composite with excellent thermal conductivity and heat dissipation showed potential application in many fields such as aviation, transportation, and seals.

One-Step Hydrothermal Synthesis of TiO2 Nanotubes and Photodegradation Activity towards Diazinon

The study aimed to analyze how variations in TiO2/NaOH mole ratio, stirring time, and washing pH affect the formation process of TiO2 nanotubes (TNT) through one-stage hydrothermal. TiO2 micro powder was mixed with 10M NaOH with the variation of TiO2/NaOH mole ratio (0.005:1, 0.015:1, and 0.025:1). The hydrothermal process was then conducted at 130 ℃ in an autoclave for 24 h with stirring time intervals of 10, 15, and 20 minutes/h. The samples underwent 1 M HCl washing to produce diverse pH variations (pH = 2, pH = 3, and pH = 4). Characterization of the synthesized TNT was conducted using SEM, TEM, XRD, SAA, and UV-Vis DRS. After analysis of the micrographs revealed the fiber shape of the particles, it was noted that TNT particle size increased due to smaller mole ratio variation, longer stirring, and lower pH. The synthesized TNT featured a tubular morphology with an inner diameter of 3.30 nm, an outer diameter of 6.15 nm, and a wall thickness of 1.64 nm. The increase in sodium titanate content of the sample results in an increase in surface area. Additionally, small pore size contributes towards an increase in both surface area and total pore size. The best result of the TNT photocatalytic test against diazinon can be observed in the fifth sample with a mole ratio of 0.025:1, stirring time of 20 minutes/h, and washing pH of 3. With an irradiation time of 210 min, diazinon degradation reached 90%. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Phase stability and energy storage properties of polycrystalline antiferroelectric BaTiO3-substituted NaNbO3 thin films

Lead-free sodium niobate (NN) thin films with varying barium titanate (BT) content and 1 mol% manganese were deposited on platinized silicon substrates by chemical solution deposition. Microstructural analysis reveals a change in nucleation mechanism, and X-ray diffraction and Raman spectroscopy confirmed a composition-driven antiferroelectric (AFE) to ferroelectric (FE) phase transition at 0.01 < x < 0.03, providing a stability interval for the AFE phase despite increasing the tolerance factor. The thin films show well-shaped ferroelectric response under applied electric field, indicating an irreversible field-induced phase transition. The composition with 7 mol% BaTiO3 showed the most promising energy storage properties (Wrec ∼5.7 J/cm3 and 68% efficiency (η)), along with excellent thermal stability up to 120 °C and largely improved cyclic stability up to 5 * 106 bipolar cycles. These findings highlight the potential of NN-based thin films as lead-free candidates for energy storage, emphasizing the importance of stabilizing the AFE phase under electric fields for practical applications.

Influence of laser intensity and BaTiO3 content on the surface properties of 3YSZ.

Zirconia-based dental implants are in direct contact with living tissues and any improvements in their bioactivity and adhesion to the tissues are highly welcome. In this study, different ratios of barium titanate (BT) were added to 3mol% yttria-stabilized zirconia (3YSZ) through conventional sintering. The laser-texturing technique was also conducted to improve the biological performance of 3YSZ ceramics. The composition and the surface of the prepared composites were characterized by X-ray diffraction and scanning electron microscopy (SEM), respectively. The roughness and surface wettability of the composites were also measured. Furthermore, MC3T3-E1 pre-osteoblast cells were used for the in vitro experiments. Cell viability was evaluated using a commercial resazurin-based method. Morphology and cellular adhesion were observed using SEM. Based on the results, the laser texturing and the barium titanate content influenced the surface characteristics of the prepared composites. The laser-textured 3YSZ/7mol% BT composites showed a lower water contact angle compared to the other samples, which indicated superior surface hydrophilicity. The cell viability and cell adhesion of 3YSZ/BT composites increased with the rise in the barium titanate content and laser power. An elongated cell morphology and apatite nucleation were also observed by the BT content. Overall, the laser-treated 3YSZ/5 and 7mol% BT composites may be promising candidates in hard tissue repair due to their good cell response.

Synthesis and Evaluation of Properties of an Additive Based on Bismuth Titanates for Cement Systems.

The development of modern building materials science involves the process of designing innovative materials that exhibit unique characteristics, such as energy efficiency, environmental friendliness, self-healing ability, and photocatalytic properties. This can be achieved by modifying cement with nano- and fine-dispersed additives that can give the material new properties. Such additives include a number of compounds based on the TiO2-Bi2O3 system. These compounds have photocatalytic activity in the near-UV and visible range of the spectrum, which can serve to create photocatalytic concretes. Here, the purpose of this scientific study was to synthesize compounds based on the TiO2-Bi2O3 system using two methods in order to identify the most optimal variant for creating a composite material and determine its properties. Within the framework of this article, two methods of obtaining a photocatalytically active additive based on the TiO2-Bi2O3 system are considered: the solid-state and citrate-based methods. The photocatalytic, mechanical and structural properties of composites containing the synthesized additive are investigated. In this study, it was found that for the creation of photocatalytic concretes, it is advisable to use cement compositions with a bismuth titanate content of 3-10 wt.%. of the cement content, regardless of the method of obtaining the additive. However, the most optimal composition is one containing 5 wt.% of the synthesized additive. It is noted that compositions containing 5% by weight of bismuth titanate demonstrate photocatalytic activity and also show an increase in strength on the first day of hardening by 10% for the solid-state method and 16% for the citrate method.

Study on effect of barium titanate concentration in epoxy-based composite towards dielectric material properties

The properties of dielectric material can be controlled either by combining new composite materials or by altering the composition between the filler and matrix materials. This paper focuses on the development of epoxy-barium titanates composites at different filler concentrations and their relationship with dielectric properties. Epoxy resins are frequently utilized for their affordability, ability to withstand high humidity and resistance to chemicals. Meanwhile, barium titanate is recognized for its high permittivity. When these two materials are combined, they can create a high permittivity value that is advantageous for the design of small and compact antennas. In this work, five samples of different epoxy resin-barium titanate composites are made, at five different volume ratios of filler (5 vol%, 10 vol%, 15 vol%, 20 vol%, and 25 vol%). A low volume of filler results in a lower permittivity value due to the quantity of filler being less than the volume of the matrix base. Adding nano powder barium titanate to the matrix base can increase the permittivity of the composite material. However, when the volume of filler is too high, it may agglomerate, which can adversely affect the electrical performance. In this work, the complex permittivity of composite materials of epoxy resin and filler barium titanate is measured between 4 and 6 GHz using the waveguide technique. The results showed that the permittivity of epoxy-barium titanate grows continuously as the filler volume increases.

Dielectric Characterization of Heterogeneous Composites Using Time Domain Spectroscopy and Microwave Test Benches in Microwave Frequency

Dielectric composite materials made of polymers and ferroelectric ceramics have recently emerged as one of the important components for applications involving the generation, transformation, and storage of sustainable energy. Because there is a trade-off between dielectric permittivity, dielectric loss, and dissipation factor, the end use is the energy storage capacity. In the present study, epoxy resin (RE)/barium titanate (BaTiO3) composite samples are prepared using the mixture cast method with new molds. The dielectric properties, such as dielectric permittivity, dielectric loss, electrical modulus, static conductivity and dissipation factors due to the concentration of barium titanate and frequency effect on the composites, are examined using two characterization methods. The objective of this study is to determine the dielectric permittivity of the material using two microwave methods, the first is time domain spectroscopy (TDS) and the second is on the X-band microwave test bench (MTB). Additionally, different empirical mixture laws are used to estimate the dielectric permittivity of our composites. It is found that an increase in filler concentration (BaTiO3) increases the effective dielectric permittivity, which is confirmed with different empirical mixture models. The findings of this research can be used for electrical devices, including sensors, wave absorbers, resonators, and antennas.

Bismuth ferrite-barium titanate system studies around morphotropic phase boundary

Nowadays, the electro-electronic industry and scientific community have a great interest in improving memory devices. A candidate is the bismuth ferrite owing to the coexistence of ferroelectricity and anti-ferromagnetism at room temperature, however, a high leakage current harms their ferroelectric properties. Thus, bismuth ferrite and barium titanate solutions improve the ferroelectric properties of bismuth ferrite and optimize the magnetoelectric coupling factor. This system is called multiferroic, materials exhibit the coexistence of ferromagnetic, ferroelectric, or ferro-elastic orders, which is of interest to the scientific physics community and electronic industry. In this paper, bismuth ferrite-barium titanate system around the morphotropic phase boundary was studied and analyzed. It was observed changes in the structural properties in function of barium titanate content. Calcination temperature was determined from thermogravimetric analysis curves to powders of bismuth ferrite-barium titanate system. Ceramic bodies were densified conventionally. Archimedes’ method was used for density measure. Ceramics with densities greater than 95% were obtained. 93% of the perovskite phase was obtained from structural results. Finally, structural properties were presented and analyzed using Mossbauer spectroscopy as complementary technique. These analyses are very important in solid state physics because to contribute to understanding the phenomenology and synthesis process of multiferroic materials.

Dielectric Relaxation and Electric Conductivity of Polyethylene Doped with Barium Titanate Particles

The frequency and temperature dependences of dielectric permittivity and electric conductivity of high-density polyethylene with the additive of monodisperse barium titanate particles are studied. It was shown that dielectric permittivity and electric conductance increase with increasing of filler concentration at all temperatures. In this case, conductivity has hopping mechanizm described by the Josher theory. The corresponding exponent parameter and activation energy decrease as well as conductivity rises with increasing of barium titanate concentration. The experimental data of dielectric permittivity are compared with the Maxwell-Garnett and Bruggeman theories.

Dielectric Behavior Investigation of Composite Materials Based on Epoxy Resin/Fe3O4/CaTiO3, SrTiO3 Using Mixture Laws

In the same matrix of epoxy resin, Fe3O4 powder was evenly mixed with one of two titanate powders, CaTiO3 or SrTiO3. The dielectric properties of these blends were evaluated using the measurement technique of time domain spectroscopy (TDS). During this work, low-frequency analyzes (DC − 300 MHz) were carried out, mainly focusing on the static permittivity and conductivity properties as a function of titanate concentrations. The results allowed us to confirm the validity and effectiveness of the modified Lichtenecker Laws (MLL). Significant agreement accord can be shown between the MLL-calculated and experimentally determined permittivity values for ternary combinations. The perspective of this research lies in the production of new materials for use in the field of telecommunications and in particular for microelectronic components.

Structural and Electrical Properties of Glass-Ceramic Ferroelectric Composite Materials

Introduction. Materials exhibiting high dielectric permittivity are relevant for use in modern ultrahigh-frequency electronics. Among them, ferroelectrics with high dielectric nonlinearity present particular interest. The electrical strength of ferroelectric materials can be increased using modern composite structures based on mixing ferroelectries and linear dielectrics - materials exhibiting simultaneously low dielectric permittivity and high electrical strength. This approach provides for the opportunity of creating new multicomponent materials with previously unattainable properties and adjusting their component composition, inclusion size and electrical properties across a wide range. In this work, on the basis of porous potassium-iron-silicate glass (KFS) obtained by ion exchange, glass-ceramic materials containing barium titanate were synthesized for use at ultrahigh frequencies.Aim. Production of glass composites by low-temperature sintering of pre-synthesized BaTiO3 (BTO) and potassium-iron-silicate glass, as well as characterization of their structural and electrical properties at ultrahigh frequencies (microwave).Materials and methods. The crystal structure and phase composition of the obtained films were studied by X-ray diffraction using a DRON-6 diffractometer by the emission spectral line CuKα1 (λ = 1.5406 Å). The dielectric permittivity (ε) of microwave samples was evaluated by the Nicholson-Ross method at room temperature using an Agilent E4980A LCR-meter.Results. According to X-ray diffraction analysis, the synthesized samples are a mixture of KFS glass, ferroelectric BaTiO3 and dielectric barium polytitanates; the ratio of the latter determines the electrical properties of the composites. Depending on the content of barium titanate, the studied samples demonstrate a dielectric constant from 50 to 270 at a dielectric loss level of 0.1...0.02. The samples subjected to annealing in an oxygen medium showed an increase in dielectric permittivity by 10.25 % and an increase in controllability with a decrease in dielectric losses by an average of two times.Conclusion. The composite composition of 70 wt % BTO /30 wt % KFS was found to be the most promising in terms of structural and electrical properties. This composite showed an increase in dielectric permittivity by 25 % and a significant increase in nonlinearity, at the same time as reducing losses by more than two times as a result of annealing in an oxygen medium.

High-performance capacitive pressure sensors Fabricated by introducing dielectric filler and conductive filler into a porous dielectric layer through a Biomimic strategy

Capacitive sensors have vast application prospects. Their dielectric layer is hardened under high pressure, the sensitivity is reduced and sensing behavior is nonlinear. To tackle this, a novel strategy is used to incorporate voids, dielectric filler and conductive filler into the dielectric layer. Firstly, “root” like dendritic colloid polyurethane (DCPU) is prepared to grasp different content of carbon nanotube (CNT) and barium titanate (BaTiO3, BT), before such hybrid filler is coated onto the backbone of PU foam. For capacitive pressure sensors, it is observed that sensitivity increases with increasing filler content. More importantly, the addition of CNT into the inner layer of hybrid filler containing BT in the outer layer leads to linear pressure sensing behavior in a wide pressure range. Furthermore, the overall performance achieves a sensitivity of 2.51 kPa−1 under 0–100 kPa and a linearity of R2 = 0.9989, and stable signals after 1000 cycles. Finally, it is successfully demonstrated that petals with a weight of 96 mg and the physiological signals of the human body such as heartbeat, swing arm amplitude, and joint bending can be detected. This work provides a new design inspiration for capacitive sensors with high sensitivity and high linearity in realizing medical health monitoring and motion detection.

Composite structures BaSrTiO3/NiFe2O4 for microwave applications

Magnetoelectric composites consisting of barium-strontium titanate and nickel ferrite mixed in various proportions were successfully synthesized by low-temperature sintering. The crystal structure of the obtained samples was studied by the X-ray diffraction and the electron microscopy. Magnetic and electrical characteristics of as-prepared and annealed in oxygen ambient samples were investigated at microwaves. Depending on the content of barium-strontium titanate and ferrite, the studied samples showed a magnetic permeability from 20 to 40 and a dielectric permittivity from 60 to 100 with a 20% increase in permittivity after annealing in oxygen stream.

Mechanism of One-Step Hydrothermally Synthesized Titanate Catalysts for Ozonation.

A titanate nanotube catalyst for ozonation was synthesized with a simple one-step NaOH hydrothermal treatment without energy-consuming calcination. The synthesized titania catalysts were characterized by X-ray diffraction (XRD), Raman, porosimetry analysis, high-resolution transmission electron microscopy (HR-TEM), Fourier transformed infrared (FTIR), and electron paramagnetic resonance (EPR) analysis. The catalyst treated with a higher concentration of NaOH was found to be more catalytically active for phenol removal due to its higher titanate content that would facilitate more OH groups on its surface. Furthermore, the main active oxidizing species of the catalytic ozonation process were recognized as singlet oxygen and superoxide radical, while the hydroxyl radical may only play a minor role. This work provides further support for the correlation between the properties of titania and catalytic performance, which is significant for understanding the mechanism of catalytic ozonation with titania-based materials.

Optimizing Barium Titanate Nanocomposite Bone Scaffolds for Biomineralization in Dynamic Compression Bioreactors Using Time-Lapsed Microstructural Imaging and Smart Thresholding

Bone scaffolds made of calcium phosphate polymer nanocomposites have limited osteoinductive properties. Piezoelectric materials have attracted considerable interest in bone tissue engineering due to their potential to promote osteogenesis through additional electrical stimulation. Time-lapsed micro-CT imaging is a time-effective tool for in vitro optimization of such scaffolds but is challenged by nanocomposites with a high attenuation coefficient, such as one containing high amounts of piezoelectric barium titanate. We used high-resolution end-point micro-CT scans combined with histology and Raman spectroscopy to screen polydopamine functionalized nanocomposites containing 3–27 vol% barium titanate for collagenous extracellular matrix formation and mineralization. All compositions showed well-connected extracellular matrix and birefringent matured collagen after seven weeks of static human mesenchymal stem cell cultures. Nevertheless, high-resolution micro-CT analysis combined with smart thresholding during image processing enabled us to observe modest differences in ECM mineralization between groups suggesting that a volume fraction of 9–21% barium titanate facilitated the formation of dense mineral clusters in the pores even in the absence of mechanical stimuli, further corroborated by Raman spectroscopy. The same image processing approach facilitated the analysis of time-lapsed micro-CT images of scaffold cultures in dynamic compression bioreactors where 9 vol% barium titanate was the best nanocomposite composition, resulting in a significant twofold increased maturation rate under dynamic conditions. On the other hand, barium titanate content of ≥15 vol% did not improve mineralization. At 27 vol%, the biomineralization of the collagenous extracellular matrix was even impeded in the nanocomposite scaffolds, as evidenced by histology stainings. Overall, our approach enables time-lapsed quantitative assessment of high X-ray absorbing nanocomposite scaffolds for biomineralization under dynamic compression, facilitating the optimization of such mechanically responsive scaffolds.

Preparation and performance study of V2O5/TiO2 catalysts supported on ceramic filter

As the country pays more and more attention to air pollution, the ceramic filter catalyst that can achieve the effects of dust removal and NO reduction simultaneously has a promising prospect. In this paper, ceramic fiber filter supported catalyst was prepared by impregnation method and tetrabutyl titanate method. The effects of vanadium content, space velocity, temperature, and tetrabutyl titanate concentration on the NO conversion of ceramic fiber catalysts were studied, and various physical and chemical methods were used for characterization. The results show that ceramic fiber had excellent multi-dimensional space and bridging structure. The NO conversion of impregnation catalyst and tetrabutyl titanate catalyst increased with the increase of vanadium content and tetrabutyl titanate concentration; At 6700h−1 and a temperature of 300°C, both catalysts can reached the highest catalytic efficiency, tetrabutyl titanate method catalyst was 93.67%. The tetrabutyl titanate catalyst can be loaded more evenly and the filtration pressure drop of the catalyst was smaller than that of the impregnation catalyst. The filtration pressure drop was increased by about 20% compared with the unsupported ceramic fiber.