Polymer-based dielectric energy storage materials have been playing critical roles in high-performance energy storage capacitors due to their high breakdown electric fields and facile processability. ...However, the low energy density and efficiency of polymer-based film capacitors limit their widespread application in various electronics products. In this contribution, we synthesized the SrBi4Ti4O15 (SBT) nanosheets with large aspect ratio by using the molten salt method and introduced them into the PVDF matrix to prepare a multilayer nanocomposite film, of which the discharge energy density and discharge efficiency were much improved. Finite element simulation results show that the addition of 2D SBT nanosheets can significantly improve the local electric field distribution of nanocomposite films. Finally, a high discharge energy density of 11.69 J cm−3 and an excellent discharge efficiency of 78.95% were simultaneously achieved in the 0/5/0 sample. This work provides a reference for polymer-based dielectrics with excellent comprehensive energy storage performance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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Regulating product selectivity in photocatalytic CO2 reduction to enhance the yield of valuable hydrocarbons remains a formidable challenge because of the diversity of reduction ...products and the competitive reduction of H2O. Herein, ultrathin Bi2O3/ Co–doped SrBi4Ti4O15 S–scheme photocatalysts (Co–BS) were synthesized using a hydrothermal method. The Bi2O3/Co–doped SrBi4Ti4O15 photocatalyst exhibited significantly higher selectivity for CH4 (62.3 μmolg−1) and CH3OH (54.1 μmolg−1) in CO2 reduction compared with pure SrBi4Ti4O15 (27.2 and 0.8 μmolg−1) and the Bi2O3/SrBi4Ti4O15 S–scheme without Co (30.2 and 0 μmolg−1). The experimental results demonstrated that the inclusion of Co into SrBi4Ti4O15 expanded the range of light absorption and generated an internal electric field between Co–doped SrBi4Ti4O15 and Bi2O3. Density functional theory calculations and other experimental findings confirmed the formation of a new doping energy level in the Bi2O3/SrBi4Ti4O15 S–scheme heterojunction after Co doping. The valence band electrons of Bi2O3/SrBi4Ti4O15 transitioned to the Co–doped level because of the interconversion between Co3+ and Co2+ under the action of the internal electric field. Furthermore, the corresponding characterizations revealed that the adsorption and electron transfer rates of the surface active sites were accelerated after Co doping, enhancing electron involvement in the photocatalytic reaction process.
This study presented a metal–doped S–scheme heterojunction approach for CO2 reduction to produce high–value products, enhancing the conversion of solar energy into energy resources.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study aims to design a Scientific Reading-based Inquiry (SRbI) model that supports argumentation skills development. The assessment of these skills refers to the Toulmin Argument Pattern (TAP), ...and the participants were Biology Education students in a state university. Furthermore, the Design-based Research (DBR) approach was adopted by combining exploratory studies, trials, and case studies as part of an iterative process. The intervention was formed based on design principles derived from literature review and findings from exploratory studies. Also, observations were made during the trial and intervention process. Data in assessments and observations of written and oral arguments were collected and descriptively analyzed. The study, in three iterations, produced a framework as the basis for the SRbI learning model, with five phases: Reading Orientation, Recapturing, Processing, Communicating, and Reviewing. Therefore, the application of this learning model had a significant impact on the development of students’ argumentation skills.
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•Strontium bismuth titanate (SBT) nanoparticles were evaluated as antibacterial agents.•The entire bacteria were destroyed after 30 h bacteria culture on the polarized SBT.•Only 24 % ...of the bacteria were destroyed by the unpolarized specimens after 30 h of culture.•Polarized SBT can effectively combat bacterial growth and prevent biofilm formation of pathogenic bacteria.•It can be considered as an alternative antimicrobial agent.
Nanoparticles of strontium bismuth titanate (SrBi4Ti4O15/SBT NPs), along with their polarized counterparts, were prepared and their ability to combat bacterial growth on the surface of biomaterials was assessed. The structural properties of the SBT NPs were analyzed using X-ray diffraction, and their effectiveness against Staphylococcus aureus pathogenic bacteria was evaluated. While the 30 h bacteria culture results showed that the bacteria were entirely destroyed by the polarized SBT, only 24 % of the bacteria were destroyed by the unpolarized specimens The results showed that polarized SBT was significantly effective against Staphylococcus aureus bacteria, and can effectively combat bacterial growth and prevent biofilm formation of pathogenic bacteria. Hence, it can be considered as an alternative antimicrobial agent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A SrBi2Ta2O9 ferroelectric sample with exposed facet is synthesized.•SrBi2Ta2O9 with {001} facet is 138 times of the pristine one for CIP degradation.•Built-in electric field along polarization ...direction promotes charge separation.•The possible degradation pathways and intermediates toxicity are analyzed.
Antibiotics have received increasing attention due to their potential adverse effects on aquatic life and human health. How to efficiently degrade them into harmless substances is a challenging subject. Ferroelectric materials with a built-in electric field can offer a strong separation ability for the photoinduced-charge pairs and are now found to be used as photocatalysts. Herein, a series of different morphologies of SrBi2Ta2O9 ferroelectric photocatalysts with high antibiotic degradation efficiency have been successfully synthesized through a molten salt method. With the addition of KCl, SrBi2Ta2O9 (SBTO 3) with exposed (001) facets shows the most excellent photocatalytic activity for decomposing tetracycline (TC) and ciprofloxacin (CIP) under visible light illumination (λ > 420 nm). The rate constants of SBTO 3 for TC and CIP degradation are 1.38 × 10–1 and 4.54 × 10–2 min–1, which are 18 and 138 times that of the unmodified sample, respectively. The enhancement of photocatalytic performance is mainly attributed to the spontaneous polarization electric field along the 001 direction which provides a strong driven force for the separation of photoinduced charges. The KPFM results also confirm that the superior photocatalytic activity is consistent with the big large surface potential changes before and after light irradiation. The possible degradation pathways and intermediates of TC and CIP were well analyzed by DFT calculation and LC-MS. The results highlight that morphology control of the ferroelectric materials exhibits enhanced photocatalytic performance for the degradation of the antibiotic.
Two antibiotics, tetracycline and ciprofloxacin, can be degraded into small molecules efficiently by one type of Aurivillius-type layered ferroelectric material SrBi2Ta2O9 under visible light irradiation. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We present a study of the dielectric properties and behaviour of dielectric resonator antennas (DRAs) based on SrBi
2
Nb
2
O
9
(SBN)-Bi
2
O
3
composites. X-ray diffraction is used for structural ...characterisation of the samples and it indicates the formation of a new phase after the addition of Bi
2
O
3
. The temperature coefficient of resonant frequency (τ
f
) is measured and the results demonstrate that the increment of Bi
2
O
3
improves the thermal stability of the composites from −345.62 to −235.02 ppm/°C. For the dielectric properties, it is observed that Bi
2
O
3
additions cause the formation of new phases, which present higher dielectric ϵ' than SBN. Our numerical simulations show that the materials operate as DRAs and that SBN-Bi
2
O
3
composites could be potential candidates for DRAs operating in the S band.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This research article is related to a bismuth oxide‐layered pseudo‐perovskite ferroelectric material and its capabilities in the area of photocatalysis. SrBi4Ti4O15 (SBT) catalyst was prepared via a ...solid‐state reaction followed by calcination at 950°C sustained over 4 h. X‐ray diffraction, X‐ray photoelectron spectroscopy, bandgap analysis, Raman spectroscopy, and scanning electron microscopy confirmed the successful synthesis of the SBT catalyst. The photocatalysis capability was checked on a methylene blue (MB) model dye. The poling of the SBT catalyst was performed under 2 kV/mm of electric field. The poling of the catalyst material played a crucial role in enhancing the photocatalytic activity. Moreover, the effect of volume (k(v)), initial concentration (k(ic)) of the MB dye, amount of catalyst (k(c)), and intensity (k(i)) of the light were examined and analyzed by the mathematical model. This study suggested that higher intensity and amount of catalyst enhance photocatalytic activity, whereas higher concentration and volume of dye suppress the photocatalytic activity. The amount of catalyst showed the highest effect on the photocatalytic activity. The rate constant is influenced by these factors and the order of influence is k(c) > k(i) > k(v) ≃ k(ic).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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•Ag and Pd are anchored on SrBi2Ta2O9 to construct CO and CH4 evolution sites.•Ag and Pd attract and accumulate the electrons originating from SrBi2Ta2O9.•The intermediate species CO* ...desorb and form CO directly on the surface of Ag.•The CO* is further hydrogenated to form CH4 on the surface of Pd.
Photocatalytic CO2 reduction in presence of H2O provides an ideal way to alleviate the greenhouse effect and obtain valuable chemicals. Constructing active sites on the surface of photocatalysts significantly affects the activity and selectivity of photocatalytic CO2 reduction, which involves a multi-electron reduction process. Herein, we anchor Ag and Pd particles on the surface of layered perovskite SrBi2Ta2O9 to build CO and CH4 evolution sites, respectively, via a photodeposition method. Ag and Pd not only attract and accumulate the photoinduced electrons originating from SrBi2Ta2O9 due to the formed Schottky junction between them, but also activate CO2 molecules, thereby resulting in higher CO2 reduction activity. On the surface of Ag, intermediate species CO* desorb and form CO directly, whereas, on the surface of Pd, intermediate species CO* is further hydrogenated to form CH4, thus resulting in different selectivity. This work offers a new avenue for developing photocatalysts with high activity and selectivity for CO2 reduction.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The regulation of cell-cholesterol efflux is not completely understood. Our aim was to assess the role of HDL- and non-HDL-related parameters in ATP-binding cassette transporter-A1 (ABCA1) and ...scavenger receptor class B-type-I (SRBI) cell-cholesterol efflux capacity (CEC) in coronary heart disease (CHD) cases and controls.
Lipids and apoA-I-containing HDL particles (by 2D gel-electrophoresis and immunodetection) were measured in 534 statin-treated CHD patients and in 1076 age-, gender-, and BMI-matched controls. ABCA1-CEC and SRBI-CEC were measured in apoB-depleted serum of 100 cases and 100 controls.
Cases had significantly higher concentrations of preβ-1 particles (88%) and ABCA1-CEC (34%) compared to controls. ABCA1-CEC was positively correlated with the concentrations of preβ-1 particles, triglycerides, small-dense (sd) LDL-C, and LDL-C in both cases and controls. Moreover, both the concentration and the functionality of preβ-1 particles (ABCA1-CEC/mg preβ-1) were positively associated with the concentrations of sdLDL-C and triglycerides. Cases had 27% lower levels of large HDL particles but similar SRBI-CEC compared to controls. SRBI-CEC was correlated positively with HDL-C, apoA-I, and large-HDL particle levels. However, the functionality of large-HDL particles (SRBI-CEC/mg large particles) was significantly and positively correlated with the preβ-1/α-1 ratio, sdLDL-C, and triglycerides.
CHD patients have significantly higher concentration, but less functional preβ-1 particles in term of cholesterol efflux capacity compared to controls. Triglyceride-rich lipoproteins have significant influence on either the concentration or the functionality or both of HDL particles and consequently HDL-CEC.
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•Coronary heart disease (CHD) patients have significantly higher ABCA1-cholesterol efflux capacity (CEC) compared to controls.•CHD patients have significantly higher concentration, but less functional preβ-1 particles, compared to controls.•TG-rich lipoproteins significantly influence the concentration and functionality of HDL particles and consequently HDL-CEC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Bismuth layer-structured ferroelectric (BLSF) compound strontium bismuth titanate (SrBi4Ti4O15, SBT) with cerium modifications have been synthesized using conventional solid-state processing. X-ray ...powder diffraction (XRPD) analyses reveal that the cerium-modified SBT ceramics have a pure four-layer Aurivillius-type structure. The dielectric, ferroelectric, and piezoelectric properties of the cerium-modified SBT ceramics are investigated in detail. The results indicate that the cerium modifications into SBT increase the densities, decrease the sintering temperature, lower the dielectric loss tanδ, and reduce the coercive filed Ec. The piezoelectric measurements show that cerium is very effective in promoting the piezoelectric properties of SBT ceramics. The SBT ceramics modified with 4mol% CeO2 (SBT-4Ce) exhibit the optimized piezoelectric properties, with a piezoelectric constant d33 of 27pC/N, which is the highest value among the modified SBT-based piezoelectric ceramics ever reported. The temperature-dependent electrical impedance and electromechanical coupling coefficients (kp and kt) reveal that the electromechanical coupling characteristics have a significant deterioration at ~400°C because of the high conductivity at high temperature. But the temperature-dependent frequency constants (Np and Nt) and thermal annealing analyses indicate the cerium-modified SBT ceramics have good thermal stabilities of piezoelectric properties up to 450°C. These results demonstrate that the cerium-modified SBT ceramics are promising materials for high temperature piezoelectric sensors applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
