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We reported new spectroscopy and photometry for four short-period binaries, which were acquired by several small telescopes in China from 2020 to 2022. From new spectrum and Large Sky Area Multiobject Fiber Spectroscopic Telescope data, we determined their spectral types of G8V for PZ UMa, G7 for MM Com, and V0685 Peg and G3 for V1055 Her. When compared to the Transiting Exoplanet Survey Satellite (TESS) light curve (LC) with a 2-min cadence, the difference between two light maxima for V1055 Her displays a 29.7-d oscillation. Utilizing the Wilson–Devinney program, we deduced 10 photometric solutions from our new and TESS data. Four binaries are W-type ones with variable O’Connell effects. For LC2022.1 (MM Com) and LC2022.9 (V1055 Her), Δmmax=Max.I–Max.II is as large as $15{{\ \rm per\ cent}}$ of variable light amplitude, which may be attributed to the spot’s migration and evolution. From the mass-luminosity diagram, the more massive components aref somewhat evolved main-sequence stars, whereas the less massive ones are overluminous as a result of energy exchange. Based on all eclipse timing residuals, the orbital period variations are preferably described by the light-travel time effects via the presence of additional companions. Their modulation periods range from 10 to 20 yr for four binaries, corresponding the companion’s mass ranging from M3 = 0.11 to 0.34 M⊙. Therefore, four solar-type short-period contact binaries (i.e. MM Com, PZ UMa, V0685 Peg, and V1055 Her) may be triple stellar systems.

The relatively large ionic radius of the Na ion is one of the primary reasons for the slow diffusion of Na ions compared to that of Li ions in de/intercalation processes in sodium-ion batteries (SIBs). Interlayer expansion of intercalation hosts is one of the effective techniques for facilitating Na-ion diffusion. For most ionic layered compounds, interlayer expansion relies on intercalation of guest ions. It is important to investigate the role of these ions for material development of SIBs. In this study, alkali-metal ions (Li+, Na+, K+, and Cs+) with different sizes were intercalated into lepidocrocite-type layered titanate by a simple ion-exchange technique to achieve interlayer modulation and those were then evaluated as anode materials for SIBs. By controlling the intercalated alkaline ion species, basal spacings of layered titanates (LTs) in the range of 0.68 to 0.85 nm were obtained. Interestingly, the largest interlayer spacing induced by the large size of Cs did not yield the best performance, while the Na intercalated layered titanate (Na-ILT) demonstrated a superior performance with a specific capacity of 153 mAh g-1 at a current density of 0.1 A g-1. We found that the phenomena can be explained by the high alkaline metal ion concentration and the efficient utilization of the active sites in Na-ILT. The detailed analysis indicates that large intercalating ions like Cs can hamper sodium-ion diffusion although the interlayer spacing is large. Our work suggests that adopting an appropriate interlayer ion species is key to developing highly efficient layered electrode materials for SIBs.

To improve the sintering performance of silicon nitride bioceramics, we explored the effect of β-SiAlON’s Z-value on the physical, chemical, and biological properties of β-SiAlON–Si3N4 composites. Results showed that the phase product was β-Si3N4. As the Z-value increased, the X-ray diffraction peaks gradually shifted to a smaller angle, the material grains were more tightly packed, and the bulk density and compressive strength increased, reaching the highest values (2.71 g/cm3 and 1157 MPa, respectively) at Z = 4. Soaking and ion-release experiments show that in an aqueous environment, a small amount of Al and Si ions were released, and no obvious decomposition occurred on the surface of the material. The biological performance showed that the growth of cultured cells in each group was in good condition, there was no obvious difference in morphology and adhesion, and the materials had good biological performance. An increase in the Z-value promotes the formation of mineralized nodules and osteogenic differentiation of MC3T3-E1 cells, which may be because the release of Si can promote osteogenic differentiation. Therefore, the addition of β-SiAlON could improve the sintering performance of β-Si3N4 without degrading its biological properties. The prepared β-SiAlON–Si3N4 composite ceramic is a latent bioceramic material.

We presented a low-precision spectrum for HI Leo, Transiting Exoplanet Survey Satellite data for V523 Cas, and new photometry for both K-type contact binaries. Comparing their light curves on different observing dates, we found small intrinsic variabilities, such as variable amplitudes for HI Leo and the varying heights around the second maxima for V523 Cas. By the Wilson–Devinney Code, we deduced six photometric solutions. The dark spot of V523 Cas may appear on the surface of the more massive component on BJD 2458768, while it disappears on BJD 2458779. Our results indicate that the two binaries are W-type shallow-contact binaries (f ≤ 10%). From the eclipse timing residuals, we found that the orbital periods may continuously increase, accompanied by one to two light-time effects due to additional bodies. The modulated periods and semi-amplitudes are P 3 = 25.8(±1.0) yr and A 3 = 0.ͩ0066(6) for HI Leo, P 3 = 114.8(±2.0) yr and A 3 = 0.ͩ0448(12), P 4 = 18.89(±0.14) yr and A 4 = 0.ͩ0025(2) for V523 Cas, respectively. The orbital period secularly increases at a rate of dP/dt = 2.86(±0.11) × 10−7 day yr−1 for HI Leo and dP/dt = 3.45(±0.07) × 10−8 day yr−1 for V523 Cas, which may be attributed to mass transfer from the secondary to the primary. With mass transferring, the shallow-contact binaries, HI Leo and V523 Cas, will evolve into the broken-contact configurations.

The nanosheet-seeding growth (NSG) technique is an interesting synthesis method for preparing two-dimensional (2D) materials by employing ultrathin nanosheets as templates. In this work, the synthesis of 2D TiO2 nanoplates using Ti0.87O2 nanosheets via the NSG process is thoroughly studied to achieve a better understanding of this process. The influence of various synthesis conditions on the morphology and phase composition has been carefully examined. The study of synthesis time reveals that the TiO2 grows in the Stranski–Krastanov mode on the templates and the growth follows second-order kinetics. It is also found that the concentration of precursors and the synthesis time are the effective parameters in controlling the thickness of TiO2 nanoplates. The phase of the sample changes from anatase TiO2 to NH4TiOF3 and the morphology changes from flake to disk with the increase in the precursor concentration. The synthesis temperature has a large influence on the morphology and thickness of the sample but has little effect on the phase composition. However, the synthesis temperature changes the color of the sample, and a high temperature enlarges the light absorption range of the sample.

We presented new CCD photometry for two contact binaries, V724 And and QR Com, which were observed during the 2020–2022 observing seasons. By using the Wilson–Devinney method, the photometric solutions were deduced from new observed data and TESS ones. Their asymmetric light curves were modeled by a dark spot on the more massive component. Results indicate that the starspot may immigrate or disappear on the surface of the active component. From the TESS observations of QR Com, it is discovered that the difference between light maxima exhibits a 29.5 day oscillation, which implies the continuous evolution of spot feathers on the timescale of several weeks. Their mass ratio and fill-out factor are q = 2.308 and f = 11.55% for V724 And, and q = 0.624 and f = 12.77% for QR Com, respectively. From the (O–C) curve, the orbital period secularly decrease at a rate of dP/dt = −1.66 × 10−7 day yr−1 for V724 And and dP/dt = −3.98 × 10−7 day yr−1 for QR Com, which was interpreted by mass transfer from the more massive component to the less massive one. With period decreasing, this kind of shallow-contact binaries, V724 And and QR Com, will evolve into the deep-contact configurations.

We presented new photometry for four short-period late-type binaries, observed by three small telescopes in China from 2020 September to 2021 December. Seven sets of light curves (including the TESS data for FY Boo) were analyzed by using the W-D method. Three binaries (V0576 Peg, V0873 Per, and FY Boo) are W-type binaries with q ≃ 2.5, while KW Psc is an A-type binary with q ≃ 0.43. Max.I−Max.II is up to 10% of variable light amplitude for the asymmetric light curves, which are modeled by a dark spot on the surface of the more massive component. Photometric results imply the existence of movement and evolution of the cool spot. From the temperature−luminosity and mass–luminosity diagrams, the more massive components are a bit evolved main-sequence stars, while the less massive ones are oversized and overluminous owing to energy exchange. Orbital period analyses indicate that the cyclic oscillations occur in the (O − C) curves. Their modulated periods approach 11 yr, which may preferably result from the magnetic activity cycle for four late-type contact binaries. With angular momentum loss through magnetic braking, these short-period contact binaries may evolve into deep-contact configurations.

K0.8Ti1.73Li0.27O4 (KLTO) is an important titanium-based anode material for lithium-ion batteries (LIBs) and is expected to become an alternative to carbonaceous materials on account of its nontoxicity, low cost, and high safety performance. However, it suffers from poor specific capacity at high charge–discharge rates due to its low conductivity and obstructed Li-ion diffusion. In this work, an Fe-doped KLTO@rGO (Fe-KLTO@rGO) composite prepared by following a simple electrostatic assembly process and its high-rate and long-cycle-life-performance as an anode in LIBs is obtained. The Fe-KLTO@rGO composite sample has an excellent specific capacity of 330 and 105 mAh g−1 at a current density of 1 C (1 C = 175 mA g−1) and 50 C, respectively. In addition, the Fe-KLTO@rGO composite sample can carry out a long cycle of 3000 cycles at a rate of 50 C, and the specific capacity remains at 127 mAh g−1.