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Transparent glass-ceramics based on ZnO–Al 2 O 3 –SiO 2 (ZAS) glass system exhibit excellent optical and mechanical properties that are dependent on crystal grains. Gahnite (ZnAl 2 O 4) was the main phase that crystallized in ZAS glass-ceramics via thermoelectric coupling treatment. The morphology and size of ZnAl 2 O 4 crystal were controlled by the electric field strength. Introduction of thermoelectric coupling field led to the refinement and dispersion of large and agglomerated ZnAl 2 O 4 crystal grains, which improved the transmission and Vickers' hardness of the ZAS-based glass-ceramics. Theoretical calculations revealed that crystal phase is the area of low electric field strength, which resulted in the migration of Zn ions (Zn2+) from glass phase to the ZnAl 2 O 4 crystal regions under the effect of thermoelectric coupling field. The decrease in the amount of Zn2+ in glass phase further limited its grain growth, and refinement of ZnAl 2 O 4 grains was achieved. This research shows an efficient and rapid approach to refine grains in ZAS glass-ceramics by application of thermoelectric coupling treatment. • In this work, it is the first time use of thermoelectric coupling field to precipitate ZnAl 2 O 4 nanocrystals in ZnO–Al 2 O 3 –SiO 2 glass-ceramics. • The application of a thermoelectric coupling field was used to refine and uniformly distribute ZnAl 2 O 4 crystals in ZnO–Al 2 O 3 –SiO 2 glass-ceramics. • The mechanism of a thermoelectric coupling field on crystal refinement is explained in detail, which provides ideas for the refinement and uniformly distribution of crystal grains. [ABSTRACT FROM AUTHOR]

In numerous fields such as digital health, soft robotics, and artificial intelligence, there is a growing demand for sensing various types of weak signals. In response to this need, flexible sensors should possess characteristics such as high sensitivity (i.e., gauge factor, GF), good conformability and high cyclic stability. So, in this study a simple method was employed to prepare flexible sensors using a polyimide (PI) fabric as a flexible substrate and hot-press molding technique. Furthermore, a strategy was proposed to adjust the GF using a macroscopic crack array. Compared to traditional film substrates, fabric substrates exhibit better conformability and can be designed into variable curvature structures, presenting greater potential for various applications. Experimental data illustrate that the designed flexible fabric sensor exhibits exceptional linearity within the 0–10% strain range, with a linearity value of 0.99747. Subsequently, an extremely simple and cheap strategy for modulating the GF was proposed based on such fabric structure. The strategy is engraving an array of cracks on the surface of the sensor. The GF of the crack arrays sensors was boosted to 25 times of that without engraved crack arrays. The sensors with and without crack arrays finally accomplished the sensing tests of finger bending signal, breathing signal, blinking signal, and speech signal successfully. Therefore, the proposed sensor preparation scheme and GF enhancement strategy in this study exhibit strong potential for applications in the field of wearable flexible electronics. [Display omitted] • The sensor utilizes a PI fabric as the flexible substrate and a hot-press molding process in its preparation. • The sensor has excellent linearity (R2 > 0.99) in its working range (10%). • The use of a macroscopic crack structure increases the sensitivity of the sensor by a factor of 25. • The sensor is capable of detecting voice signals and a variety of motion signals. [ABSTRACT FROM AUTHOR]

The Li 2 O–Al 2 O 3 –SiO 2 (LAS) glass ceramics are prepared by one-step thermoelectric treatment. The influence of thermoelectric treatments on LAS glass-ceramics were studied. The crystal phase composition and microstructure of the LAS glass-ceramics were investigated by DSC, SEM, XRD and FTIR. Moreover, the thermal expansion performance and light transmittance of LAS nanocrystalline glass were characterized. The results show that low-expansion transparent LAS nanocrystalline glass can be produced in a short time by thermoelectric treatment. The free energy of nucleation and the degree of polymerization of the glass network are reduced by the electric field. The key is that the electric field polarizes Ti and Zr ions at the crystallization temperature, so that the crystal nuclei repel the same poles. This allows uniform crystal distribution, promotes crystallization and reduces one-step crystallization of crystal agglomeration. This proves that the rapid preparation of nanocrystalline glass by the one-step method is feasible, and provides a reference for the future one-step processing of glass-ceramics. • Thermoelectric treatment promotes crystallization in LAS nanocrystalline glass. • It eliminates crystal agglomeration in LAS nanocrystalline glass. • It can rapidly produce low-expansion transparent LAS nanocrystalline glass. [ABSTRACT FROM AUTHOR]

The variable temperature characteristics of isobaric phase transition process for zeotropic mixture can effectively reduce the heat transfer irreversibility between working fluids and heat sources or heat sinks for thermodynamic cycle systems. One of the key problems in the application of zeotropic mixtures for power generation systems is how to determine their optimal components and compositions. The traditional method is mainly based on the exhaustive method, which means that every considered component and their compositions in the mixture are optimized one by one and mainly caused by the independence and discontinuity of components. This process will consume a large amount of computing resources, which limits the optimization of zeotropic mixtures. In order to describe the discrete components and optimize them, the selective coefficient representing every component alternative is introduced and this paper recommends a simultaneous approach to achieve the optimal components and compositions of zeotropic mixture at the same time. Two case studies with different heat sources and sinks as well as system layouts are illustrated to show the proposed approach. Besides, it also proves the systems with zeotropic mixture have better performance than that of systems with pure fluid. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the irreversible loss of the condensation process for the traditional LNG power generation system is too large, this paper presents four different two-stage condensation Rankine cycles based on different arrangements of pumps and turbines. The effects of the operating conditions (the first-stage and second-stage condensation temperatures) and various working fluids on the performance of the four cycles with different structures are investigated. The results show that when the arrangement of the turbines is the same, the arrangement of the pumps (series or parallel) has little effect on the net output power. However, when the arrangement for the pumps is the same, the arrangement for the turbines has a significant effect on the net output power. When the working fluid is n-pentane and the turbines are of series arrangement, the maximum net output power is increased by about 17% compared with the condition that the turbines are of parallel arrangement. In addition, for the same cycle, whether the isentropic efficiency of turbine is a constant value or not has a significant effect on the maximum net output power, the optimal operating conditions, and the optimal working fluid. [ABSTRACT FROM AUTHOR]

In Sharir and Solomon (2015), Sharir and Solomon showed that the number of incidences between m distinct points and n distinct lines in R 4 is (1) O ∗ m 2 ∕ 5 n 4 ∕ 5 + m 1 ∕ 2 n 1 ∕ 2 q 1 ∕ 4 + m 2 ∕ 3 n 1 ∕ 3 s 1 ∕ 3 + m + n , provided that no 2-flat contains more than s lines, and no hyperplane or quadric contains more than q lines, where the O ∗ hides a multiplicative factor of 2 c log m for some absolute constant c . In this paper we prove that, for integers m , n satisfying n 9 ∕ 8 < m < n 3 ∕ 2 , there exist m points and n lines on the quadratic hypersurface in R 4 { ( x 1 , x 2 , x 3 , x 4 ) ∈ R 4 ∣ x 1 = x 2 2 + x 3 2 − x 4 2 } , such that (i) at most s = O ( 1 ) lines lie on any 2-flat, (ii) at most q = O ( n ∕ m 1 ∕ 3 ) lines lie on any hyperplane, and (iii) the number of incidences between the points and the lines is Θ ( m 2 ∕ 3 n 1 ∕ 2 ) , which is asymptotically larger than the upper bound in (1) , when n 9 ∕ 8 < m < n 3 ∕ 2 . This shows that the assumption that no quadric contains more than q lines (in the above mentioned theorem of Sharir and Solomon (2015)) is necessary in this regime of m and n . By a suitable projection from this quadratic hypersurface onto R 3 , we obtain m points and n lines in R 3 , with at most s = O ( 1 ) lines on a common plane, such that the number of incidences between the m points and the n lines is Θ ( m 2 ∕ 3 n 1 ∕ 2 ) . It remains an interesting question to determine if this bound is also tight in general. [ABSTRACT FROM AUTHOR]

• A Cu/EHEA composite was successfully fabricated via solid–liquid bonding. • Good metallurgical interface bonding was achieved by the element mutual diffusion. • The interface of Cu/EHEA composites possessed an excellent bonding strength. • An increase in hardness on the Cu side was associated with the formation of precipitates. In the present work, a layered composite consisting of pure copper (Cu) and AlCoCrFeNi 2.1 eutectic high entropy alloy (EHEA) was fabricated via solid/liquid bonding. The results demonstrated that the interface of Cu/EHEA layered composites had a good bonding strength. The element diffusion and mechanical property of the interface were analyzed. In the diffusion layer, no crack defects were formed. The interface microhardness was about 210 HV. The tensile strength of the Cu/EHEA composite was ∼ 150 MPa, indicating that the interface strength was higher than that of pure Cu. The layered Cu/EHEA composite is a promising candidate with the excellent comprehensive performance. [ABSTRACT FROM AUTHOR]

• An improved multi-timescale coordinated control strategy is proposed to be used in an integrated energy system. • A hybrid energy storage system is introduced into the system. • Operating costs and carbon emissions are considered as the optimization objectives. • General rules for sizing hybrid energy storage system are proposed in this paper. In view of the complex energy coupling and fluctuation of renewable energy sources in the integrated energy system, this paper proposes an improved multi-timescale coordinated control strategy for an integrated energy system (IES) with a hybrid energy storage system (HESS). The power response characteristics of various devices in IES at different time scales are analyzed which shows that the multi-timescale coordinated control method can be well coupled with the IES including HESS. The advantages of HESS over single energy storage system in stabilizing power fluctuation and extending energy storage life are compared and analyzed while the control method of supercapacitor under multi-time scale coordinated control strategy is proposed. The primary energy consumption, operating costs, carbon dioxide emissions and load shedding costs are considered the optimization objectives in the day-ahead rolling optimization stage according to the day-ahead forecast renewable energy (RE) data. In the intraday rolling adjusting stage, the proposed method can reduce the effect of the RE day-ahead forecasting errors to achieve the intraday energy scheduling balance and ensure the safe operation of the devices of IES. Considering the background of IES with a high proportion of renewable energy, this paper makes innovative use of the advantages of HESS to improve the power response characteristic of the system. The high-frequency part of RE is balanced by HESS in the real-time coordinated control stage. A typical structure of IES is applied and the simulation results are analyzed to show the performance of the proposed method in this paper. Moreover, general rules for sizing of HESS are also proposed. The influence of the hybrid energy storage capacity allocation ratio on battery capacity loss and carbon emission reduction is discussed. The Pareto front including the configuration and cost of supercapacitor has been obtained. As shown in the case, the application of HESS in the IES can improve the power response characteristic, extend the lithium-ion battery (LiB) life and has more benefits in reducing carbon emissions. [ABSTRACT FROM AUTHOR]

The isothermal phase transition process of pure working fluids cannot effectively match the liquefied natural gas (LNG) gasification process, resulting in low efficiency of LNG cold energy power generation systems. In order to improve the temperature matching characteristics, mixed working fluids with a temperature glide during the phase change process can be adopted. In our previous study, the two-stage condensing process also effectively improved the temperature matching characteristics; thus, this paper presents a two-stage condensation combined cycle using zeotropic mixtures, and the effects of the type and number of components for mixed refrigerants on the two-stage condensing combined cycle system performance are studied. With the net power output as the objective function, the evaporation temperature, condensing temperatures, LNG expander inlet temperature, and working fluid mole fractions are optimised by the genetic algorithm. The results demonstrate that the net power output of n-C 5 H 12 is the largest among the studied pure fluids. The net power output of the binary mixed working fluid at the optimum mole fractions is obviously superior to that of pure working fluids. The system performance is improved when the hydrocarbon mixture is selected as a working fluid, and the optimum number of components is three. [ABSTRACT FROM AUTHOR]

For the low efficiency of the traditional power generation system with liquefied natural gas (LNG) cold energy utilization, by improving the heat transfer characteristic between the working fluid and LNG, this paper has proposed a two-stage condensation Rankine cycle (TCRC) system. Using propane as working fluid, compared with the combined cycle in the conventional LNG cold energy power generation method, the net power output, thermal efficiency and exergy efficiency of the TCRC system are respectively increased by 45.27%, 42.91% and 52.31%. Meanwhile, the effects of the first-stage and second-stage condensation temperature and LNG vaporization pressure on the performance and cost index of the TCRC system (net power output, thermal efficiency, exergy efficiency and UA) are analyzed. Finally, using the net power output as the objective function, with 14 organic fluids (such as propane, butane etc.) as working fluids, the first-stage and second-stage condensation temperature at different LNG vaporization pressures are optimized. The results show that there exists a first-stage and second-stage condensation temperature making the performance of the TCRC system optimal. When LNG vaporization pressure is supercritical pressure, R116 has the best economy among all the investigated working fluids, and while R150 and R23 are better when the vaporization pressure of LNG is subcritical. [ABSTRACT FROM AUTHOR]

• PIV used to study flow fields & turbulence in 5x5 rod bundle across 22 cases (Reynolds: 310-12296). • Higher turbulence intensity at lower Reynolds due to significant relative velocity gradient in rod bundle. • Transition Reynolds ≈ 900 in rod bundle, less distinct than in pipes. • Fluctuation velocity decreases with Reynolds, abrupt rise at transition Reynolds. • Non-uniform transition Reynolds leads to varying turbulence intensity in rod bundle. Utilizing the particle image velocimetry (PIV) technique, this study investigates the fully developed flow field and turbulence statistics in a 5×5 rod bundle across 22 cases, with Reynolds numbers ranging from 310 to 12296.Time-averaged, statistical, and spectral analyses were performed on the full field and instantaneous velocity vectors obtained through PIV measurements to examine the velocity distribution, turbulence characteristics, and spectral features in different subchannels under various Reynolds numbers. In conjunction with a differential pressure transmitter, the flow properties and fluid transitions were also explored.The experimental results reveal that the relative velocity gradient in the rod bundle channel is more significant at lower Reynolds numbers. As the Reynolds number increases, the relative velocity distribution becomes more uniform. A comparison of experimental results from different planes indicates that the fluctuation velocity in the gap subchannel is greater than that in the inner subchannel, suggesting that tightly arranged rods can generate higher turbulence intensity. Furthermore, the transition observed through the friction factor in the rod bundle channel is less distinct than those in pipes, with the transition Reynolds number being approximately 900. A low Reynolds number effect is present in the rod bundle channel, where the dimensionless fluctuation velocity decreases as the Reynolds number increases. Upon reaching the transition Reynolds number, the area-averaged dimensionless fluctuation velocity abruptly rises. By examining the turbulence intensity variations at different positions within the rod bundle, it becomes evident that the transition Reynolds numbers vary across different subchannel positions. Ultimately, the experimental data can be employed to validate the applicability of turbulence models for different Reynolds numbers. [ABSTRACT FROM AUTHOR]

A chemical conversion method for the protection of the surface weathering stone artworks was explored. By this method, the harmful calcium sulfate weathering layer on the stone relics was converted into a protective calcium oxalate layer in situ . The calcium oxalate conversion layer was characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD) and polarizing microscope (PLM). The conversion layer was also estimated by chromatic aberration, capillary suction, adhesive force and dissolution stability tests. The calcium oxalate conversion layer with good weatherability, adherence and compatibility will be promising as a solution for the protection of the surface weathering rock relics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Regions where feed-in tariff higher than valley price should follow dual objective optimization. • The economy of the household PV-BES-EV system mainly depends on the purchase cost of EVs. • Decreasing electricity price will not undermine the effectiveness of the household PV-BES-EV system. • The energy bills and carbon emissions decrease significantly with the optimal scheduling schemes. The household PV-BES-EV system (photovoltaic - battery energy storage - electric vehicle system) connected to the grid can guarantee the electricity demand of the household and facilitate the flexible trade with the grid to achieve the goals of cutting energy bills and reducing carbon emissions. In related issues, past studies often assume that renewable energy is both economical and environmentally friendly, and thus regarded it as the primary power source. While in fact, in some regions where the feed-in tariff is higher than the sales price at a certain time, households may be driven by arbitrage opportunities to frequently purchase electricity from the grid at the certain time to gain benefits, resulting in far greater carbon emissions than expected within the household measurement boundary. To avoid the environmental burden caused by pure economic incentives and to provide practical and sustainable solutions consistent with various energy price policies, the optimal scheduling schemes of the household PV-BES-EV system that considers both economic and environmental incentives for different scenarios solved by the genetic algorithm is proposed in this paper. Household data in Shanghai, China and Hamburg, Germany were selected for modelling, representing the dual-objective optimization scenario with arbitrage opportunities and the single-objective optimization scenario with sales price higher than feed-in tariff, respectively. Results show that for urban and rural residents in Shanghai, the energy bill and carbon emission would decline about 105%, 48% and 88%, 62%, respectively. As for Hamburg, the accordingly results would be 69% and 64%. In addition, based on the cost-effectiveness of the system in long-term, this paper puts forward policy recommendations that align with local conditions to further improve the economy of the system. [ABSTRACT FROM AUTHOR]

Esophageal squamous cell carcinoma (ESCC) is one of the deadliest digestive tract cancer with poor prognosis. In our previous comprehensive genomics study, we identified that hotspot mutations in the solute carrier family 35 member E2 (SLC35E2) promoter region was significantly associated with worse prognosis in patients with ESCC. However, the biological function and molecular mechanism of SLC35E2 remains unclear. This study was to investigate the malignant function and mechanism of SLC35E2 in ESCC. Western blotting and qRT-PCR were used to assess the expression of SLC35E2 in ESCC cell lines. Luciferase assay and chromatin immunoprecipitation (ChIP) assay were used to assess the transcriptional inhibition of KLF4. Incucyte cell proliferation assay, colony formation assay and subcutaneous tumor formation in nude mice were used to assess the malignant function of SLC35E2. SLC35E2 can promote ESCC cell proliferation in vitro and in vivo. Krüppel-like factor 4 (KLF4), a transcriptional repressor in ESCC, binds to the SLC35E2 promoter and represses the expression of SLC35E2. The transcriptional suppression of KLF4 can be blocked by the mutation at −118 site of the SLC35E2 promoter. Besides, the accumulation of SLC35E2 expression contributes to the malignant phenotype of ESCC. These results indicate that SLC35E2 may be used as a biomarker for prognosis as well as a therapeutic target for patients with ESCC. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of fluorination on VPLi cathode investigated for the first time. • V4+ content is ranged from 16.3% to 23.8%. • VF 4 and Li 3 VF 6 converted into LiVP 2 O 7 increasing specific capacity. • The charge transfer from Li to O contributed to the cycle stability. Vanadium-based amorphous materials are an emerging category of lithium ion battery cathodes with high specific capacity and high voltage performance. In this study, we investigated the effect of fluorination on the performance of an amorphous vanadium-phosphorus-lithium (VPLi) cathode for lithium ion battery applications. Results show that the fluorinated product consists Li 3 VF 6 and VF 4 nanocrystals embedded in an amorphous phase when the V4+ content was in the range of 16.3% to 23.8%. VPFLi has an optimal specific capacity of 344.3 mAh g−1 in the first cycle and 269.7 mAh g−1 after 200 cycles at a current of 50 mA g−1 within the voltage range of 1.5–4.2 V. VPLi has an amorphous structure, and the reversible V4+/V5+ lithiation process corresponds to the conversion between V 2 O 5 and Li 2 V 2 O 5 during the charge–discharge cycle. Compared to VPLi, VF 4 and Li 3 VF 6 crystals were found to convert into LiVP 2 O 7 in VPFLi, which led to the increased specific capacity. Simulation based on density functional theory show that fluorine for oxygen has led to the movement of Fermi level moves towards the edge of the conduction band. Charge mostly transferred from Li to O which contributed to the improved cathode stability. This study provides a new perspective towards selecting novel cathode for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• First report to control the precipitation of crystal grains under thermoelectric coupling. • The number of crystal grains gradually increases with the electric field voltage. • Fracture of the Ti-O-Si bond causing [TiO 4 ] will be transformed to [TiO 6 ]. MgO–Al 2 O 3 –SiO 2 (MAS) the basic glass was prepared by the traditional melt-quenching method, whereas the glass-ceramics was produced by subjecting the glass to thermoelectric coupling treatment. The MAS glass-ceramics were characterized by FTIR, XPS, and SEM. Clearly, the extension of the heat-treatment time did not change the crystal grains number in the absence of an electric field. However, with the electric-field voltage increase,the crystal grains number in the MAS glass-ceramics gradually increased when the electric-field voltage became steady at 1200 V. At high temperatures, Ti4+ participates in the silicon-oxygen network with four coordinations and produces good miscibility with the melt. By the introduction of electric field into the glass, a high amount of titanium transforms from a titanium-oxide tetrahedron to a titanium-oxide octahedron. Titanium was separated from the silicon–oxygen network framework to form a crystal nucleus and promote crystal growth. This study provides insights into the relationship between electric-field and glass-ceramics nucleation. [ABSTRACT FROM AUTHOR]

The vanadium-based amorphous electrode material can realize the valence state conversion and increase its specific capacity through the multi-electron reaction. We have obtained V 2 O 5 –Li 3 PO 4 glass with a strong reducing agent CaC 2 , realizing a multi-electron reaction of V5+ to V4+ and then to V3+ in the model system. Moreover, we have explored the relationship between valence state, crystallinity, and conductivity limit to compare the cycle performances of amorphous glass batteries. The CaC 2 content of 20%, V4+ presented the dominating valence state with a content of 77.5%. VP-C20% exhibited a maximum specific capacity of 319.3 mAh g−1, and the specific capacity after 100 cycles was 280.3 mAh g−1, corresponding to a retention capacity of 87.8%. The electrochemical performance of amorphous vanadium oxide decreased with the increase of the LiV 2 O 5 's nanocrystallinity. Crystallinity and the controllable multi-electron reaction could provide an important reference for designing other new electrode materials with high capacity and long cycle life. Image 1 • Vanadium-based amorphous electrode material could realize valence state conversion. • V5+ was reduced to V4+, then to V3+ with CaC 2 , as reducing agent. • V4+ enhanced ion and electron transport and cycling stability. • The performance decreased with the increase of LiV 2 O 5 's nanocrystallinity. [ABSTRACT FROM AUTHOR]