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Vacuum induction melting is a more energy-efficient process for the preparation of a titanium alloy with good homogeneity and low cost. But the crucial problem for this technology is in developing a crucible refractory with high stability. In the present work, a novel (Ca,Sr,Ba)ZrO3 crucible was prepared by slip casting and its performance in melting NiTi alloy was studied. The results showed that a single solid solution was formed with a homogeneous distribution of metal elements after sintering at 1500 °C. It was found that the total content of oxygen and nitrogen remaining in the TiNi alloy after melting in the (Ca,Sr,Ba)ZrO3 crucible was 0.0173 wt.%, which fulfills the ASTM standard on biomedical TiNi alloys. The good resistance of the (Ca,Sr,Ba)ZrO3 crucible to molten NiTi has a relationship with the sluggish diffusion effect of high-entropy ceramics. This study provides insights into the process of designing highly suitable crucible material for melting a NiTi alloy. [ABSTRACT FROM AUTHOR]

High‐entropy single‐phase rare earth titanates (RE0.2Gd0.2Ho0.2Er0.2Yb0.2)2Ti2O7 (RE = Sm, Y, Lu) were designed and synthesized successfully, in which their lattice distortion was quantitatively described by mass disorder and size disorder. It is worth mentioning that (Y0.2Gd0.2Ho0.2Er0.2Yb0.2)2Ti2O7 could obtain the low thermal conductivity (1.51 W·m−1·K−1, 1500°C), high thermal expansion coefficient (average, 11.69×10−6 K−1, RT ∼1500°C) and excellent high‐temperature stability. In addition, the relationship between the microstructure and thermal transport behaviors has been studied at the atomic scale. Due to the disorder of A‐site ions, severe lattice distortion occurred in specific crystal planes, and the large mass difference between Y3+ and other RE3+ further causes mass fluctuation and results in lower thermal conductivity. Compared with YSZ, the high‐entropy rare earth titanate (Y0.2Gd0.2Ho0.2Er0.2Yb0.2)2Ti2O7 has lower thermal conductivity, higher thermal expansion coefficient, and excellent high‐temperature stability, which has great potential for application in the thermal protection field. [ABSTRACT FROM AUTHOR]

The primary objective of the current fire protection system in high-rise buildings is to extinguish fires in close proximity to the detectors. However, in the event of rapidly spreading fires, it is more effective to limit the transmission of fire and smoke. This study aims to develop an IoT-based real-time pre-response system for high-rise building fires that is capable of limiting the spread of fire and smoke. The proposed system collects fire data from sensors and transmits them to a cloud computer for real-time analysis. Based on the analysis results, the cloud computer controls the actions of alarm devices, ventilation equipment, and fine water mist nozzles. The system can dynamically adjust the entire system's behavior in real time by adopting pre-response measures to extinguish fires and limit the spread of fires and smoke. The system was tested on a simulation platform similar to actual high-rise buildings to evaluate its impact on fires and smoke. The results demonstrate the system's effectiveness in extinguishing fires and suppressing the spread of fires and smoke. [ABSTRACT FROM AUTHOR]

To satisfy the demand for rapid prediction of smoke transmission paths in high-rise building fires, a graph-based model was developed. The model represents a high-rise building as a Directed Acyclic Graph (DAG) grid model and employs computer simulation to determine the smoke transmission path and generate prediction results. The results were compared with those from similar simulations and were found to be consistent, indicating the feasibility and objective nature of the prediction results. Compared to other methods, this model has a shorter modeling time and can quickly provide prediction results. Furthermore, it can be applied to buildings of any structure, thus serving as a reference for smoke control design in high-rise building fire protection systems, particularly in cases involving complex internal structures. [ABSTRACT FROM AUTHOR]

To study the effects of the reciprocal grafting on the photosynthesis of two genotypes tomato offspring under selenium stress, red ball cherry tomato cherry 5-5-1 and yellow ball cherry tomato yellow RTY-3-2 post-grafting generation (red scion, red rootstock, yellow scion and yellow rootstock) and seedlings (red CK and yellow CK) planted in 10 mg·kg-1 selenium soil, and the pot experiment was carried out to study the effects of the reciprocal grafting on the growth characteristics and the photosynthesis of tomato offspring under selenium stress. The results showed that grafting increased the fresh weight of the organs of the offspring, the ratio of root to shoot, and the functional activity of the roots of the plants, which was conducive to the growth of tomato offspring. Simultaneously, it could effectively improve the photosynthetic capacity of grafted offspring leaves at the seedling stage. The grafted offspring of rootstocks had the best effect on improving the net photosynthetic rate, stomatal conductance and transpiration rate and stomatal conductance of tomato leaves, and decreased intercellular CO2 concentration. Among them, the best effect of yellow rootstock was to provide ideas and theoretical basis for the production of selenium-enriched tomatoes in the selenium-deficient areas in the future.

Zinc is an essential nutrient for plant growth and development. Zinc deficiency affects plant photosynthesis and nitrogen metabolism. In this experiment, 'Shine Muscat' grape was used as experimental material. Three soil application levels of zinc sulfate were set up, which were 2 kg/667 m2, 3 kg/667 m2 and 4 kg/667 m2, respectively. The time of applying zinc fertilizer in soil was 10 days after flowering, and the time of spraying zinc fertilizer was divided into 21 days after flowering, 35 days after flowering, 21 days and 35 days after flowering, respectively, once (twice in total), with no zinc fertilizer as control (CK). The results showed that the application of zinc sulfate 3 kg/677 m2 on soil 10 days after flowering, 0.3% zinc sulfate fertilizer on leaves 21 days after flowering and 35 days after flowering increased zinc content in grape leaves and fruits, and significantly increased net photosynthetic rate of grape leaves.

A pot experiment was conducted to study the effects of different biochar types [addition of rape straw biochar (RB), addition of paddy straw biochar (PB), addition of wheat straw biochar (WB) and addition of corn straw biochar (MB)] on the soluble sugar content and plant height of peach seedlings. The result showed that the soluble sugar content in roots and leaves of peach seedlings treated with biochar was lower than the control. However, the soluble sugar content in stems was higher than control compared with the control. In the soluble sugar content in the aboveground part, there was no significant difference between the treatment of adding biochar and the control except for the treatment of PB. All the treatment of adding biochar increased the plant height of peach seedlings except the treatment of MB than the control and the treatment of RB and PB were at a higher level. Compared to control, all biochar addition treatments increased stem diameter of peach seedlings and the treatment of RB and PB were at a higher level. Therefore, the treatment of RB and PB was beneficial to the growth of peach seedlings.

Thermal protection materials with high optical reflectivity, low thermal conductivity, and good high‐temperature stability are required for the development of laser technologies and the protection of the critical equipment components. Herein, we synthesize a novel thermal protective material, La0.9Sr0.1Ti1−xNbxO3+δ (LSTN; x = 0.1, 0.125, 0.15), with different Nb5+‐ion contents using solid‐state sintering. Phase structure analysis demonstrates that LSTN (x = 0.1, 0.125, 0.15) presents a single‐phase monoclinic structure with a uniform element distribution. In particular, the LSTN0.125 ceramic exhibits ultrahigh optical reflectivity (96%, 2300 nm) and excellent thermophysical properties, such as a high thermal expansion coefficient (10.3 × 10−6 K−1, 1000°C), an ultralow thermal conductivity (0.408 W (m K)−1, 300°C), and excellent high‐temperature stability. Aberration‐corrected scanning transmission electron microscopy reveals that the disordered substitution of Nb5+ ions induces numerous lattice distortions and mass fluctuations, which decrease the thermal conductivity, and makes difference in the relative refractive indices of atomic layers causing the high reflectivity of the material. These remarkable properties render the LSTN0.125 ceramic as an ideal alternative for near‐infrared thermal protection applications. [ABSTRACT FROM AUTHOR]

Thermal protection materials with high optical reflectivity, low thermal conductivity, and good high‐temperature stability are required for the development of laser technologies and the protection of the critical equipment components. Herein, we synthesize a novel thermal protective material, La0.9Sr0.1Ti1−xNbxO3+δ (LSTN; x = 0.1, 0.125, 0.15), with different Nb5+‐ion contents using solid‐state sintering. Phase structure analysis demonstrates that LSTN (x = 0.1, 0.125, 0.15) presents a single‐phase monoclinic structure with a uniform element distribution. In particular, the LSTN0.125 ceramic exhibits ultrahigh optical reflectivity (96%, 2300 nm) and excellent thermophysical properties, such as a high thermal expansion coefficient (10.3 × 10−6 K−1, 1000°C), an ultralow thermal conductivity (0.408 W (m K)−1, 300°C), and excellent high‐temperature stability. Aberration‐corrected scanning transmission electron microscopy reveals that the disordered substitution of Nb5+ ions induces numerous lattice distortions and mass fluctuations, which decrease the thermal conductivity, and makes difference in the relative refractive indices of atomic layers causing the high reflectivity of the material. These remarkable properties render the LSTN0.125 ceramic as an ideal alternative for near‐infrared thermal protection applications. [ABSTRACT FROM AUTHOR]