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• A strategy to optimize the bond characteristics by introducing Ta5+ is proposed. • Structural properties on MgNb 2− x Ta x O 6 (0 ≤ x ≤ 0.8) solid solutions are clarified. • Considerably enhanced Q × f (∼ 170,000 GHz) is achieved when x = 0.6. • The theory associated with low dielectric loss of MgNb 2 O 6 system is enriched. With the increasing frequency of wireless mobile communication, dielectric materials with higher Q × f are required to enhance the signal strength of microwave passive devices and thus compensate for the rapid attenuation of high-frequency signals during propagation. In order to improve the Q × f of the MgNb 2 O 6 system and study the internal mechanism between the structure and microwave dielectric properties, Ta5+ ion is introduced to design and fabricate MgNb 2− x Ta x O 6 (0 ≤ x ≤ 0.8) ceramics by the solid-state reaction method. The single columbite phase and dense structure are observed throughout the entire composition range. All elements (Mg, Nb, Ta, and O) can be detected by X-ray photoelectron spectroscopy. Insights from the Raman spectroscopy and group theoretical analysis reveal that the A g(2) and A g(3) modes located at ∼ 905 cm−1 dominate the Raman vibration. In addition, the ɛ r depends on the polarizability reflected by the C–M equation and Raman shift. The τ f closely relates to the bond energy of the Nb/Ta–O bond and restoring force characterized by average octahedral distortion of [Nb/TaO 6 ]. Notably, the crucial factors for the huge improvement of Q × f are clarified deeply, in terms of the lower internal strain, the reduced ordering-induced domain size, and the chemical bond valence closer to the ionic valence state, which promotes the stability of crystal structure. Moreover, the introduction of lower electronegative ions enhances the ability of electrons to compensate for oxygen vacancies, thereby reducing the dielectric loss caused by the conductance. Excellent microwave properties (ɛ r = 19.2, Q × f = 170,000 GHz, and τ f = −55.6 ppm °C–1) are achieved in MgNb 1.4 Ta 0.6 O 6 ceramic, specifically a nearly 40% increase in the Q × f. This work has enriched the theory associated with low dielectric loss and provided the MgNb 1.4 Ta 0.6 O 6 ceramic with a pretty high- Q × f for the application in the design of the 5G/6G wireless communication devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Metamaterials, from concept to application level, is currently a high-trending topic. Due to the strict requirements of the simultaneous reasonable structural design and stability of materials, the construction of a high-performance metamaterial for extreme environments is still difficult. Here, combining metamaterial design with materials optimization, we propose a completely different strategy and synthesize a type of monomeric ceramic meta-atom to construct metamaterials. Based on a geometric design with multiple degrees of freedom and dielectric properties, hybrid anapole modes with impedance matching can be produced, experimentally inducing nearly perfect absorption with high temperature stability (high tolerable temperature of approximately 1300 °C, with almost zero temperature drift) in microwave/millimeter-wave bands. We surpass the oxidation temperature limitation of 800 °C in conventional plasmonic absorbers, and provide an unprecedented direction for the further development of integrated high-performance metamaterial wireless sensors responding to extreme environmental scenarios, which will also lead to a new direction of specific ceramic research toward device physics.

The exploration of two-dimensional (2D) anode materials with fascinating theoretical specific capacity and ion diffusion rate has been paid much attention in the domain of alkali ion batteries. In this present contribution, the potency of monolayer Janus SnXY (X/Y = O, S, Se, Te, X ≠ Y) to function as an anode material for Na-ion batteries (SIBs) is anticipated upon the ground of first-principles calculations. The outcomes indicate that the cohesion energies of all the SnXY are positive, signifying that they are energetically stabilized. The distribution of electrons in the SnXY structure is strongly dependent on the electronegativity of the atoms on both sides, and the higher the electronegativity, the more electrons are gathered. Meanwhile, the larger (smaller) charge transfer between Sn atoms and X/Y atoms enhances (weakens) the bond strength and leads to a decrease (increase) in the interlayer spacing. In service, Na atoms tend to be steadily adsorbed at the top of O, Sn, Se and Te, and a large number of electrons are transferred from Na atoms to SnXY. SnXY exhibits a metallic state after embedding, increasing its own electrical conductivity. Particularly, the SnSSe has a low diffusion barrier of 0.12 eV and a high Na storage capacity of 1380 mAh/g. These insights demonstrate that monolayer Janus SnXY is a prospective anode material for SIBs possessing high storage capacity and rapid charge/discharge rates.

The conceptualization and deployment of electrode materials for rechargeable sodium-ion batteries are key concerns for next-generation energy storage systems. In this contribution, the configuration stability of single-layer GeSiBi2is systematically discussed based on first-principles calculations, and its potential as an anode material is further investigated. It is demonstrated that the phonon spectrum confirms the dynamic stability and the adsorption energy identifies a strong interaction between Na atoms and the substrate material. The electronic bands indicative of inherent metallicity contribute to the enhancement of electronic conductivity after Na adsorption. The multilayer adsorption of Na provides a theoretical capacity of 361.7 mAh/g, which is comparable to that of other representative two-dimensional anode materials. Moreover, the low diffusion barriers of 0.19 and 0.15 eV further guarantee the fast diffusion kinetics. These contributions signal that GeSiBi2can be a compatible candidate for sodium-ion batteries anodes.

A novel transparent conductive conductor composed of a silver nanowire (AgNW) network and MoOxon a flexible polyethylene terephthalate (PET) substrate, with contemporaneously improved adhesion and reduced resistivity, is prepared using the full-solution process without high-temperature annealing. Under the optimized conditions, a MoOx/AgNW/MoOxmultilayer is achieved, which shows much superior optoelectronic performance to that obtained from ITO with a high optical transmittance of 89.2% and a low sheet resistance of ∼12.5 Ω/sq. Unlike pure AgNW films, the sheet resistance is little changed after the tape and ultrasonication tests, illustrating a very strong adhesion to the PET substrate after the encapsulation of MoOx. Moreover, the multilayer film exhibits excellent stability to resist mechanical bending and acid damage. In addition, the successful implementation of the flexible transparent heater demonstrates the practical application value of the electrode.

A novel method of fabricating flexible thin-film transistor based on single-crystalline Si nanomembrane (SiNM) with high-kNb2O5–Bi2O3–MgO (BMN) ceramic gate dielectric on a plastic substrate is demonstrated in this paper. SiNMs are successfully transferred to a flexible polyethylene terephthalate substrate, which has been plated with indium-tin-oxide (ITO) conductive layer and high-kBMN ceramic gate dielectric layer by room-temperature magnetron sputtering. The BMN ceramic gate dielectric layer demonstrates as high as ∼109 dielectric constant, with only dozens of pA current leakage. The Si–BMN–ITO heterostructure has only ∼nA leakage current at the applied voltage of 3 V. The transistor is shown to work at a high current on/off ratio of above 104, and the threshold voltage is ∼1.3 V, with over 200 cm2/(V s) effective channel electron mobility. Bending tests have been conducted and show that the flexible transistors have good tolerance on mechanical bending strains. These characteristics indicate that the flexible single-crystalline SiNM transistors with BMN ceramics as gate dielectric have great potential for applications in high-performance integrated flexible circuit.

In order to improve the performance of transparent conductive Al-doped ZnO (AZO)/Cu/Al-doped ZnO multilayer thin films, multilayer thin films of titanium-embedded AZO/Cu/AZO structures have been designed and deposited onto flexible polycarbonate substrates to develop an indium-free transparent flexible electrode. The effect of Ti layer on the structural, optical, and electrical properties of multilayer thin films was investigated. The experiments reveal that the AZO/Ti/Cu/AZO fabricated in argon-oxygen mixtures has the best performance (commutation quality factor of 422.0): resistivity of 3.85×10^−5  Ω·cm, sheet resistance of 4.31  Ω/sq, carrier concentration of 1.65×10^22  cm^−3, mobility of 9.87  cm^2/Vs, and acceptable luminous transmittance of above 82% in the visible range.

Objective To determine the quantity and quality of articles in the field of knee arthroplasty worldwide and elucidate the characteristics of global scientific production.Methods Web of Science was used to identify articles in the field of knee arthroplasty from 2011 to 2015. The total number of papers, number of papers per capita, total number of citations, and mean number of citations were collected.Results In total, 11,590 papers were identified. The number of publications significantly increased from 2011 to 2015. Most originated from North America, East Asia, and West Europe. Most (88.51%) were from high-income countries, 11.48% were from middle-income countries, and only 0.01% were from lower-income countries. The United States had the most articles and total citations. Sweden had the highest mean citations, followed by Denmark and Canada. However, when adjusted by population size, Denmark had the most articles per million population, followed by Switzerland and the Netherlands.Conclusions The number of knee arthroplasty publications has rapidly increased in recent years. The United States is the most prolific, but some European countries are more productive relative to their population.

This paper studies the development of hybrid thin‐film transistors in recent years based on patents and articles from companies in the display field. Including the comparison of the design concept of the hybrid thin‐film transistor by Apple and LG, and the improvement of the possible problems raised by the company. Finally, the application prospects and development trends of hybrid thin‐film transistors are analyzed.

Background: This study aimed to explore the clinical values of the percutaneous spinal endoscopy “isolation zone” technique for discogenic low back pain (DLBP). Methods: This retrospective case series study enrolled patients with intervertebral DLBP treated with the percutaneous spinal endoscopy “isolation zone” technique in the department of Orthopedics, Cangzhou central Hospital affiliated to TianJin Medical University between September 2017 and September 2020. Results: Forty-five patients with DLBP were enrolled. The mean operation time was 94.7 ± 17.7 min. The visual analogue scale (VAS) score of lumbosacral pain was 6.95 ± 1.02 before operation, 2.64 ± 0.71, 1.80 ± 0.54, 1.42 ± 0.50, and 1.27 ± 0.45 at 1, 3, 6, and 12 months after operation, respectively. The Oswestry disability index (ODI) score of low back pain was 72.84 ± 5.95 before operation, 35.1 ± 5.30, 25.22 ± 4.85, 16.78 ± 4.63, and 10.91 ± 2.36 at 1, 3, 6, and 12 months after operation, respectively. At final follow-up, the treatment effect based on modified MacNab criteria was excellent in 24 cases, good in 13 cases, and fair in 8 cases. The excellent/good rate was 82.2%. Conclusion: The percutaneous spinal endoscopic “isolation zone” technique seems to be a promising surgical alternative for DLBP.

In order to identify potential protein targets involved in colorectal cancer(CRC), we used a liquid chromatography coupled with mass spectrometry(LC-MS)/MS-based proteomics approach to characterize global protein expression patterns in malignant tissues and their adjacent healthy tissues from Dukes C stage CRC patients. A total number of 34 differentially expressed proteins were detected and identified by LC-MS/MS and database searching, which are supposed to be relevant to progression of colorectal tumor. Among these proteins, nucleophosmin 1(NPM1) was found to be remarkably up-regulated in colorectal carcinoma tissues, as compared with that in their normal counterparts. The results presented here could provide clues to elucidate the pathological significance of NPM1 in regulation of carcinogenesis of Dukes C stage colorectal tumors.

Previously, we reported that Coxiella-like, Rickettsia-like and Arsenophonus-like symbionts could simultaneously coexist in Dermacentor silvarum. In this study, we examined their burdens and population dynamics in a single host during the host life cycle using quantitative PCR. Our results showed that multiple symbionts exhibited different abundances and varying trends in the tick host. Coxiella-like and Rickettsia-like symbionts were found at high densities in large quantities that fluctuated with time. This may coincide with oogenesis and mating of the host. Our findings provide insight into symbiont–tick interactions that lay the foundation for future studies.

Human periostin was over-expressed in HEK293T cells, which was enriched by nickel ion affinity resin, and further purified by gel electrophoresis. Phosphopeptides contained in the tryptic digestion of the purified periostin were enriched by TiO2affinity chromatography, and then analyzed by liquid chromatography-tandem mass spectrometry(LC-MS/MS). LC-MS/MS analysis reveals three phosphorylation modification sites of periostin at IKVIEGpSLQPIIK(682–694), pSLHEKLKQDK(498–507) and p[TT]VLYEC*C*PGYM*R(73–85). The established method could be a great help to profiling the phosphorylation status of periostin under different physiological environments, such as inflammatory and tumor micro-environments.

Abstract

The structure and dielectric properties of perovskite Ag(Nb0.8Ta0.2)O3 ceramics were explored. A small amount of Bi2O3 was used to modify the dielectric properties of the ceramics. The addition of Bi2O3 led the ceramics to a high densification and optimal dielectric properties. With the addition of 4.5 wt% Bi2O3, the permittivity of Ag(Nb0.8Ta0.2)O3 ceramics increased from 470 to 733, the dielectric loss decreased from 62×10−4 to 6.7×10−4, and the temperature coefficient of capacitance, TCC, decreased from 2004 ppm/°C to −50 ppm/°C. The high permittivity obtained was due to the high densification and weak Ta-O or Nb-O bond strength in the oxygen octahedron that results from the addition of Bi2O3.

Abstract: The structure and dielectric properties of perovskite Ag(Nb0.8Ta0.2)O3 ceramics were explored. A small amount of Bi2O3 was used to modify the dielectric properties of the ceramics. The addition of Bi2O3 led the ceramics to a high densification and optimal dielectric properties. With the addition of 4.5 wt% Bi2O3, the permittivity of Ag(Nb0.8Ta0.2)O3 ceramics increased from 470 to 733, the dielectric loss decreased from 62×10-4 to 6.7×10-4, and the temperature coefficient of capacitance, TCC, decreased from 2004 ppm/°C to -50 ppm/°C. The high permittivity obtained was due to the high densification and weak Ta-O or Nb-O bond strength in the oxygen octahedron that results from the addition of Bi2O3.

Fracture failure analysis on ultra supercritical turbine bolts was carried out by means of chemical composition analysis, mechenical properties testing, metallographic examination and fracture analysis. The results show that the main reason of the bolts fracture is high temperature stress-rupture, with the fracture morphology being intergranular cracking character. The main fracture is perpendicular to the axial direction of bolt, which indicates that the tensile working stress result in the crack. In addition, another kind of cracks which is 45oof the axis has been found on the bolt. It indicates that there must be some abnormal torsion stress on the bolt which most possibly be caused during assembling process.

Fracture failure analysis on ultra supercritical turbine bolts was carried out by means of chemical composition analysis, mechenical properties testing, metallographic examination and fracture analysis. The results show that the main reason of the bolts fracture is high temperature stress-rupture, with the fracture morphology being intergranular cracking character. The main fracture is perpendicular to the axial direction of bolt, which indicates that the tensile working stress result in the crack. In addition, another kind of cracks which is 45oof the axis has been found on the bolt. It indicates that there must be some abnormal torsion stress on the bolt which most possibly be caused during assembling process.