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A series of barium zirconate modified potassium sodium niobate-based lead-free piezoelectric ceramics [(0.97-x)(K0.45Na0.55)(Nb0.97Sb0.03)O3-0.03Bi0.5K0.075Na0.425ZrO3-xBaZrO3, KNNS–BKNZ–xBZ, x = 0 ~ 0.02] were prepared by the traditional solid-state method. The effect of BZ on the phase structure and electrical properties was systematically studied. Rhombohedral–orthorhombic–tetragonal multiphase coexistence structure can be observed for the whole ceramic system while the addition of BZ leads to the reduction in the orthorhombic phase content and increase in the rhombohedral and tetragonal phase content. At the critical composition with x = 0.01, the ceramics show the optimized electrical properties with the piezoelectric constant d33 of 265 pC/N, unipolar strain Suni of 0.168%, inverse piezoelectric coefficient d33* of 480 pm/V, room-temperature dielectric constant εr of 1634, and Curie temperature TC of 282 °C. Moreover, enhanced temperature stability was achieved in the x = 0.01 ceramics, presenting the variation of d33 less than 15% within the temperature range of 20–100 °C and the Suni remained above 80% until the elevated temperature of 175 °C. [ABSTRACT FROM AUTHOR]

In this work, Ca-doped lithium manganese oxides Li0.98Ca0.02Mn2O4 were successfully synthesized via a facile hydrothermal method followed by calcination. The evolution of the microstructures and electrochemical performance were investigated in detail. XRD identified that pure spinel phase with the enlarged lattice constants were observed in Ca-doped samples. SEM revealed that powders had a hollow hemispherical morphology composed of stacked nanoparticles. Ca doping can improve the electrochemical performance of LiMn2O4. Galvanostatic charge-discharge tests demonstrated that Li0.98Ca0.02Mn2O4 calcined at 550°C could deliver the initial discharge capacity of 108.6 mA h/g with the capacity retention of 91.4% after 100 cycles at 2 C. The results indicate that Ca-doped LiMn2O4 is a promising cathode material. [ABSTRACT FROM AUTHOR]

Background: Various experimental studies demonstrated that atorvastatin exerted additive effects with anticancer drugs to impair tumor growth, delay relapse, and prolong survival time in lung cancer. However, it is indistinct whether there are survival benefits of atorvastatin in the treatment of small-cell lung cancer (SCLC) patients with dyslipidemia. Therefore, this study aimed to evaluate the efficacy and safety of atorvastatin plus first-line standard chemotherapy in SCLC combined dyslipidemia. Methods: This was a retrospective analysis of 91 eligible SCLC patients with dyslipidemia registered at the First Teaching Hospital of Tianjin University of Traditional Chinese Medicine from October 2018 to October 2022. SCLC patients with confirmed dyslipidemia were assigned to the treatment group to receive atorvastatin plus first-line standard chemotherapy (n = 45) or to the control group to accept chemotherapy (n = 46) until disease progression or unmanageable toxicity occurred. The clinicopathological parameters and survival data were collected and analyzed. Univariate and multivariate analyses were performed to investigate the prognostic significance of SCLC. The median progression-free survival (mPFS) was considered to be the pivotal symbol as the primary endpoint. The second endpoints were recognized as the median overall survival (mOS) and toxicity. Results: In the total of 91 enrolled patients, the curative effect can be evaluated in all patients. Research results showed that atorvastatin added to first-line standard chemotherapy was associated with a significant improvement in survival (mPFS: 7.4 vs 6.8 months, P = 0.031; mOS: 14.7 vs 13.2 months, P = 0.002). Conclusion: Atorvastatin added to first-line standard chemotherapy achieved prospective efficacy and manageable safety in SCLC combined dyslipidemia. [ABSTRACT FROM AUTHOR]

Gas–liquid interface behavior directly affects the smelting energy efficiency, furnace life and precious metal yield during the copper anode slime smelting process in a Kaldo furnace. In this work, a 1:4.5 cold water experimental model was constructed by geometrically scaling down an industrial Kaldo furnace based on the similarity principle. The gas–liquid cavity shape in a Kaldo furnace under the synergetic effect of various process parameters was systematically studied from the perspectives of computer image analysis and dimensional analysis. The results showed that the influences of the gas flow rate Q and injection lance height h on the shape of the cavity had strong regularity. With increasing Q and h values, the shape of the cavity regarding the penetration depth Hp/D and area Sp/D2 in the molten pool increased and decreased, respectively. The influences of rotation speed ω and liquid volume fraction φ on the shape of the cavity were relatively complex; however, the effect of liquid viscosity μ was not significant. In addition, a mathematical correlation was developed for the dimensionless Hp/D and Sp/D2 as a function of ω, φ, h, μ and the modified Froude number Fr′. [ABSTRACT FROM AUTHOR]

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The apparent incompatibility between d33 and Qm in potassium sodium niobate-based lead-free ceramics is an obstacle to their applications. In this study, (K0.5Na0.5)0.98Li0.02Nb0.82Ta0.18O3 (LT-KNN) system near the orthorhombic–tetragonal (O–T) phase boundary but in the O phase region is selected as the matrix to ensure a relatively large d33 and high Tc, and help the CuO doping generate an effective "hardening" effect to improve Qm. The results show that adding proper amount of CuO into LT-KNN promotes the densification of ceramics and suppresses the abnormal grain growth, which helps to decrease the dielectric loss and obtain a high poling efficiency. Moreover, the Cu2+ doping in B-site (Nb/Ta)5+ generates oxygen vacancies ( V O ∙ ∙ ) and the Cu Nb / Ta ″ ′ - V O ∙ ∙ ′ defect dipoles could be formed, resulting an obvious "hardening" effect. With the introduction of 1 mol% CuO, the d33 increases from 82 to 180 pC/N and the Qm presents an abrupt rise from 136 to 665. More intriguingly, the addition of CuO delays the O–T phase transition while maintaining a high Tc of ~ 310 °C. Combined with the pinning effect of internal bias field, the d33 of 1 mol% CuO doped LT-KNN ceramics shows favorable stability in the wide temperature range of 20–280 °C, and a high Qm of larger than 250 can be achieved until 100 °C. Such a superior comprehensive electromechanical performance makes the ceramics promising in applications of high-power and high-frequency devices. [ABSTRACT FROM AUTHOR]

Considering the current global goal of carbon neutrality, the relationship between cultivated land intensive use (CLIU) and carbon emission efficiency (CEE) should be explored to address the global climate crisis and move toward a low-carbon future. However, previous work in this has been conducted at provincial/regional scales and few have identified the spatial correlation between CLIU and CEE at the scale of large river basins. Therefore, this study explored the spatiotemporal characteristics of CLIU, cultivated land carbon emissions (CLCE), and CEE, as well as the spatial correlation between CLIU and CEE in the Yellow River Basin (YRB), China. A comprehensive evaluation model, the Intergovernmental Panel on Climate Change (IPCC) coefficient methodology, existing data envelopment analysis model, and bivariate spatial autocorrelation models were used to analyze statistical data from 2005 to 2017. We found that the overall CLIU and CLCE values in the YRB exhibited a continuous increase; the average carbon emission total efficiency and carbon emission scale efficiency first decreased and then increased, and the average carbon emission pure technical efficiency gradually decreased. Areas of high CLCE were concentrated in eastern areas of the YRB, whereas those of high CLIU, carbon emission total efficiency, carbon emission scale efficiency, and carbon emission pure technical efficiency predominantly appeared in the eastern areas, followed by central and western areas of the YRB. Spatial analysis revealed a significant spatial dependence of CLIU on CEE. From a global perspective, the spatial correlations between CLIU and CEE changed from positive to negative with time. Moreover, the aggregation degree between CLIU and CEE gradually decreases with time, while the dispersion degree increases with time, and the spatial correlation gradually weakens. The local spatial autocorrelation further demonstrates that the number of high–low and low–high clusters between CLIU and CEE gradually increases over time, while the number of high–high and low–low clusters gradually decreased over time. Collectively, these findings can help policymakers formulate feasible low-carbon and efficient CLIU policies to promote win–win cooperation among regions. [ABSTRACT FROM AUTHOR]

NaNbO3-based lead-free ceramics show great potential in energy storage and piezoelectric applications due to the antiferroelectric and ferroelectric features. However, pure NaNbO3 usually shows lossy hysteresis loops because of the metastable antiferroelectric phase at room temperature. In this work, Bi(Zn2/3Nb1/3)O3 was introduced into NaNbO3 to modulate the phase structure, dielectric, and energy storage properties. The addition of Bi(Zn2/3Nb1/3)O3 changed the phase structure from orthorhombic to pseudo-cubic, decreased the grain size from ~ 20 μm to ~ 1 μm, shifted the temperature of dielectric peak from 360℃ to room temperature, and led to much-reduced polarization hysteresis and improved breakdown strength. With the addition of 9 mol% Bi(Zn2/3Nb1/3)O3, the maximum recoverable energy density of 3.3 J/cm3 was achieved under 33.5 kV/mm. These results provide a feasible route to design and fabricate new NaNbO3-based energy storage ceramics. [ABSTRACT FROM AUTHOR]

Ferroelectric nanolaminates have drawn wide attention due to the process convenience of atomic layer deposition (ALD) method and their superior performance. In this work, HfO2/ZrO2 nanolaminates were prepared by alternately depositing HfO2 and ZrO2 single layer with ALD technology. The crystal structures and electrical properties were comprehensively investigated and analyzed. Compared with HfZrO4 solid solution, HfO2/ZrO2 nanolaminates showed much lower leakage current density and similar ferroelectricity, which was beneficial for the improvement of device life. The highest remnant polarization of 17.7 μC cm−2 was achieved in HfO2/ZrO2 nanolaminates with a ratio of 12:12, exhibiting a good endurance of exceeding 5 × 109 cycles. The effects of film thickness and laminated structure on the electrical properties and fatigue performance were also discussed. The differences in ferroelectricity and leakage current were originated from the different grain sizes. The small roughness, fine grains and enough crystallization are essential for the better ferroelectric properties. This work provides a comparison between doped films and laminated films and reveals the thickness dependence on the ferroelectric properties of HfO2/ZrO2 nanolaminates. [ABSTRACT FROM AUTHOR]

Lead-free piezoelectric ceramics featuring high piezoelectricity and fatigue resistance are extremely important in practical applications. In this work, 0.85Bi0.5Na0.5TiO3–0.11Bi0.5K0.5−xRbxTiO3–0.04BaTiO3 (x = 0–0.20) ceramics are developed, and the effects of Rb content on the crystalline phase, domain structure, electric property, and fatigue resistance are investigated. XRD results show that all the ceramics exhibit the rhombohedral/tetragonal morphotropic phase boundary. The introduction of Rb at A-sites induces enhanced relaxor characteristics. Increasing the Rb content leads to apparently decreased size and increased dynamics of ferroelectric domains, as revealed by the PFM and TEM observations. Notably, the fatigue resistance of ceramics is greatly improved with the introduction of Rb. In particular, the composition of x = 0.10 exhibits almost fatigue-free behaviors in conjunction with high piezoelectricity of d33 ~ 203 pC/N, which can be attributed to the formation of tweed-like nanodomains with a size of 10–20 nm and stripe-like nanodomains with an average width of ~ 3.5 nm. [ABSTRACT FROM AUTHOR]

Printed electronics enable the fabrication of large-scale, low-cost electronic devices and systems and thus offer significant possibilities in terms of developing new optoelectronic application in various fields. Organic photodetectors (OPDs) represent an emerging organic optoelectronic device, which have attracted extensive attention due to many advantages such as low cost, mechanical flexibility and chemical tailoring. Herein, flexible bulk heterojunction (BHJ) OPDs are fabricated on polyethylene terephthalate (PET) substrate by large-scale roll-to-roll (R2R) micro-gravure printing technique using the novel printable ink, which consists of a conjugated polymer named PBDB-T and a nonfullerene small molecule named IT-M. The device photoresponse covers the range from ultraviolet (UV) to visible light (Vis). Meanwhile, OPDs show a high photoresponsivity (R) up to 4.18 A/W and a good detectivity (D*) as high as 1.11 × 1011 Jones. Under the different bending curvature or after being bent 5000 times, the flexible OPDs still well maintain the performance parameters. Furthermore, the large-area OPD arrays exhibit good uniformity and high stability in atmospheric conditions without any encapsulation for 40 days. This work reports the high-quality PBDB-T/IT-M BHJ used for UV–Vis photodetectors, which provides an innovation pathway to develop high-performance, flexible OPDs processed via large-scale, low-cost R2R printing technique. [ABSTRACT FROM AUTHOR]

As the electronic industry developed rapidly, greater demands are required on the performance of dielectric composites, such as high permittivity, low dielectric loss, and high-energy density. Improving the compatibility of fillers in polymer matrix and uniform distribution of the electric field could increase the permittivity of such composites. Therefore, BaTiO3 nanoparticles were coated by TiO2 sol to fabricate BaTiO3@TiO2 core-shell structured fillers in this paper. BaTiO3@TiO2 fillers with gradient permittivity were firstly modified by dopamine in order to disperse in the composites homogeneously and adhere to poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) matrix tightly. At 1 kHz, the permittivity of the composite with 20 vol% BaTiO3@TiO2 was 32.15, obviously larger than that of pure P(VDF-HFP) (6.92), and the dielectric loss was just 0.052. Consequently, the discharged energy density of the composite was enhanced to 0.23 J/cm3 at 40 kV/mm, which was two times higher than that of pure P(VDF-HFP). This work provides a feasible approach to prepare high-performance dielectric composites. [ABSTRACT FROM AUTHOR]

Long-alkyl tail triphenylene (TP) side-chain liquid crystalline polymers (SCLCPs) with different spacer length (P-m-TP, m = 2, 3, 4, 6, 8, which is the number of carbon atom in the flexible alkyl spacers) have been successfully synthesized via free radical polymerization. The differential scanning calorimetry (DSC), polarized light microscopy (POM), ultraviolet-visible spectroscopy (UV-Vis), wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) measurements were performed to investigate the influence of multiple effects on the self-organization behaviors of P-m-TP, including steric effect, decoupling effect and π-π stacking effect. The experimental results revealed that P-m-TP (m = 2, 3, 4) formed the columnar phase which was developed by the TP moieties and the main chain as a whole, suggesting that the side-chains had strong steric effect even though the number of spacer length (m) exceeded 4. In addition, the clearing points (Tis) of the polymers were above 300 °C. When m = 6 and 8, the polymers displayed hexagonal columnar phase and exhibited the low Tis (91 and 80 °C respectively), originating from the self-assembly of triphenylene due to the decoupling effect and π-π stacking effect. This work offers a viable and inspiring pathway to control the phase transition temperature and phase structure of TP SCLCPs via simply tailoring the spacer length and increasing the alkyl tail length of TP. [ABSTRACT FROM AUTHOR]

Dielectric composites are of great demand in the micro-electronics industry. To enhance the energy storage density of the composites, TiO2 nanowire clusters was synthesized by a hydrothermal method and incorporated into the P(VDF-HFP) polymer matrix in this work. The microstructure, dielectric properties of the prepared film were discussed and the effects of TiO2 loading on the energy density were investigated. The results shows that the TiO2 clusters were tightly blended to the P(VDF-HFP) matrix owing to the dopamine-modified interface. The dielectric constant increased with the loading of TiO2, the maximum dielectric constant reached 12.04 with 7.5 vol% TiO2 loading at 1 kHz, as compared to 5.01 for the neat P(VDF-HFP). The enhanced dielectric constant was attributed to the interface polarization originated from the large interface area between the TiO2 nanowire and polymer matrix. The discharged energy density of the composite significantly increased to 1.35 J/cm3 with 7.5 vol% TiO2 nanowire clusters, which was two times higher than that of the neat P(VDF-HFP) at the same condition. The findings of this work can shed a light on improving the energy density of energy storage device via morphology modification. [ABSTRACT FROM AUTHOR]

Ag/TiO core-shell nanowires were synthesized via a one-step solution method without using a template. The structural and optical properties of the as-synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-Vis absorption spectroscopy. The analysis was carried out for understanding the contribution of different content of silver for enhancing the photocatalytic activity of TiO. The good photocatalytic activity has been proven in the porous Ag/TiO nanowires. Noticeably, the Ag/TiO nanowires exhibits excellent reusability, and can be applied to the degradation of various organic dyes, such as methyl orange (MO) and rhodamine-B (RhB). A possible photocatalytic mechanism is processed. This unique Ag/TiO nanowires photocatalyst proved to have great potentials for organic contaminants degradation in wastewater. [ABSTRACT FROM AUTHOR]

Submicro α-FeO coatings were formed using electrophoretic deposition (EPD) technique in aqueous media. The zeta potentials of different α-FeO suspensions with different additives were measured as a function of pH to identify the optimum suspension condition for deposition. Electrophoretic depositions of α-FeO coatings under different applied electric fields and deposition time were studied and the effects of applied voltages and deposition time on deposition rates and thicknesses were investigated. The particle packing densities of the deposits at various applied voltages and deposition time were also analyzed by a scanning electron microscope (SEM). The results show that crack-free α-FeO coatings with uniform microstructure and good adherence to the nickel substrates are successfully obtained. Electrophoretic deposited α-FeO coating from aqueous suspension is a feasible, low-cost and environmental friendly method. [ABSTRACT FROM AUTHOR]

Microstructure, dielectric properties, and ferroelectric relaxor behavior of Ca doped barium strontium titanate (BSCT) ceramics prepared by solid-state reaction were investigated. It was demonstrated that the unit cell volume of the BSCT ceramics firstly decreases with the increase of Ca contents up to x = 0.08, but increases with further addition of Ca ( x ≥ 0.12). The shrinkage of the unit cell volume resulted from the substitution of Ba by Ca when x ≤ 0.08, which enhanced the relaxor behavior of the ferroelectrics. Conversely, a small amount of Ca substituted for Ti site when x ≥ 0.12, which weakens the relaxor behavior of the BSCT ceramics. The 8 mol % doped BSCT ceramic yielded the maximum index of relaxation ( γ) of 1.90 and made it a promising candidate for future industrial application of efficient and eco-friendly relaxor ferroelectric materials. [ABSTRACT FROM AUTHOR]

An efficient fractal method based on discrete wavelet transfer is proposed in this paper. Before encoding, images with one-level wavelet transform are first partitioned into four subbands, which classify the range blocks as four types. An accelerated fractal coding method called variance sorting (VS) scheme with high reconstructed quality is addressed for the low-frequency components. Hereafter, the low-frequency part rebuilt performs one-level wavelet decomposition once again. The first-level high-frequency subbands excluding the diagonal directions are predicted according to the next coarser frequency scale in the same directions. Simulation experimental results compared with other classification algorithms demonstrate that the proposed method can obtain high compression ratio and reduce the encoding time without significant loss in the reconstructed image quality. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish and optimize high-performance thin-layer chromatography (HPTLC) analysis of gatifloxacin and related substances by the method of design of experiment (DOE). First, preliminary screening of 22 solvents was performed using uniform design (UD) to establish the developing solvent proposed to be optimized. The optimal proportions of components in the developing solvent were established by using central composite design (CCD) to establish and validate HPTLC analysis of gatifloxacin and related substances. Using DOE, it was found that the optimal proportions (by volume) of components in the developing solvent in the HPTLC analytical method were methanol-1,2-dichloroethane-concentrated ammonia solution-acetonitrile (2.8:7.2:0.5:0.5, v/v). Methodological validation showed that the established HPTLC method could separate gatifloxacin and 8 related substances with similar structures effectively. In particular, impurity pairs with the greatest separation difficulty (due to their similar polarities and dipole moments), e.g., impurity #3 (8-fluorogatifloxacin) and impurity #8 (gatifloxacin 2-methylpiperazine), impurity #3, and substance #9 (gatifloxacin), could also be separated effectively. The HPTLC method was simple, accurate, reliable, and suitable for rapid qualitative analysis of gatifloxacin and related substances in routine tests. Additionally, the analytical results presented here may provide useful supplemental information on the current reversed phase high-performance liquid chromatography (RP-HPLC) method, especially in terms of the mechanism of normal-phase separation. [ABSTRACT FROM AUTHOR]

Piezoelectric actuators are widely utilised in adaptive optics to enable mirrors having an actively controlled reflective surface for the purpose of the wavefront correction by reducing the effects of rapidly changing optical distortion. Two new prototype adaptive X-ray optical systems are under development with the aim of approaching the fundamental diffraction limit. One proposed technology is microstructured optical arrays (MOAs) involving two or four piezoelectric strips bonded to a silicon wafer to produce a micro-focused X-ray source for biological applications, and which uses grazing incidence reflection through consecutive aligned arrays of channels obtained using deep silicon etching. Another technology is large scale optics which uses a thin shell mirror bonded with 20-40 piezoelectric actuators for the next generation of X-ray telescopes with an aim to achieve a resolution greater than that currently available by Chandra (0.5"). PZT-based piezoelectric actuators are being developed in this programme according to the design and implementation of the proposed mirror and array structures. Viscous plastic processing is chosen for the preparation of the materials system, which is subsequently formed and shaped into the suitable configurations. Precise controls on the thickness, surface finish and the curvature are the key factors to delivering satisfactory actuators. Unimorph type piezoelectric actuators have been proposed for the applications and results are presented regarding the fabrication and characterisation of such piezo-actuators, as well as the related design concepts and comparison to modelling work. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

The transforming-growth-factor-β-activated kinase TAK1 is a member of the mitogen-activated protein kinase kinase kinase family, which couples extracellular stimuli to gene transcription. The in vivo function of TAK1 is not understood. Here, we investigated the potential involvement of TAK1 in cardiac hypertrophy. In adult mouse myocardium, TAK1 kinase activity was upregulated 7 days after aortic banding, a mechanical load that induces hypertrophy and expression of transforming growth factor β. An activating mutation of TAK1 expressed in myocardium of transgenic mice was sufficient to produce p38 mitogen-activated protein kinase phosphorylation in vivo, cardiac hypertrophy, interstitial fibrosis, severe myocardial dysfunction, 'fetal' gene induction, apoptosis and early lethality. Thus, TAK1 activity is induced as a delayed response to mechanical stress, and can suffice to elicit myocardial hypertrophy and fulminant heart failure. [ABSTRACT FROM AUTHOR]

There is a growing need for high energy density capacitors in modern electric power supplies. The creation of nanocomposite systems based on one-dimensional nanofibers has shown great potential in achieving a high energy density since they can optimize the energy density by exploiting both the high permittivity of ceramic fillers and the high breakdown strength of the polymer matrix. In this paper, BaTiO3 nanofibers (NFs) with different aspect ratio were synthesized by a two-step hydrothermal method and the permittivity and energy storage of the P(VDF-HFP) nanocomposites were investigated. It is found that as the BaTiO3 NF aspect ratio and volume fraction increased the permittivity and maximum electric displacement of the nanocomposites increased, while the breakdown strength decreased. The nanocomposites with the highest aspect ratio BaTiO3 NFs exhibited the highest energy storage density at the same electric field. However, the nanocomposites with the lowest aspect ratio BaTiO3 NFs achieved the maximal energy storage density of 15.48 J/cm3 due to its higher breakdown strength. This contribution provides a potential route to prepare and tailor the properties of high energy density capacitor nanocomposites. [ABSTRACT FROM AUTHOR]