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The qualities of the materials employed to manufacture concrete are significantly impacted by high temperatures, which results in a noticeable decrease in the material’s strength characteristics. Concrete must be worked very hard and allowed to reach the required compressive strength (fc). Nevertheless, a preliminary estimation of the desired outcome may be made with an outstanding degree of reliability by using supervised machine learning algorithms. The study combined the Dingo optimization algorithm (DOA), Coot bird optimization (COA), and Artificial rabbit optimization (ARO) with Random Forests (RF) evaluation to determine the fc of concrete at high temperatures. The abbreviations used for the combined methods are RFD, RFC, and RFA, respectively. Remarkably, removing the temperature (T) parameter from the input set leads to a remarkable 1100% improvement in the effectiveness index (PI) and normalized root mean squared error (NRMSE), while causing a significant fall in the coefficient of determination (R2). The findings suggest that all RFD, RFC, and RFA have substantial promise in properly forecasting the fc of concrete at high temperatures. More precisely, the RFD algorithm demonstrated exceptional precision with R2 values of 0.9885 and 0.9873 throughout the training and testing stages, respectively. Through a comparison of the error percentages for RFD, RFC, and RFA in error-based measurements, it becomes evident that RFD exhibits an error rate that is about 50% smaller compared to that of RFC and RFA. This prediction is crucial for various industries and applications where concrete structures are subjected to elevated temperatures, such as in fire resistance assessments for buildings, tunnels, bridges, and other infrastructure. By accurately forecasting the compressive strength of concrete under these conditions, engineers and designers can make informed decisions regarding the material’s suitability and performance in high-temperature environments, leading to enhanced safety, durability, and cost-effectiveness of structures. [ABSTRACT FROM AUTHOR]

The pollution of antibiotics in aquatic environments has received extensive attention. Yet, research on antibiotic contamination in river-lake systems, a significant form of modern aquatic environments, still needs to be explored. This study focuses on the Chaohu Basin (China) investigating the occurrence characteristics, influencing factors, and risk assessments of antibiotics in the river-lake system. The total antibiotic concentrations in the water phase and sediment phase were 3.14–1887.49 ng/L and 0.92–1553.75 ng/g, respectively. Clindamycin was the predominant antibiotic in the water phase, whereas tetracycline prevailed in the sediment phase. Notable differences in concentration and structural composition of antibiotics between the tributaries (river system) and Chaohu Lake were observed, indicating the involvement of various geochemical processes in the attenuation of antibiotics during transport to the receiving lake. Spatial analysis suggested that the western river is the primary source of antibiotics in Chaohu Lake. Controlling nutrient influx in heavily polluted areas is crucial to addressing the escalating issue of antibiotic pollution in the river-lake system. The widespread occurrence of clindamycin in the waters is likely due to wastewater treatment plant discharges, and high-intensity human activities continue to exacerbate antibiotic contamination. Risk assessment indicated that sulfamethoxazole, tetracycline, lincomycin, and clindamycin ranked in the top four with the highest risks to the most sensitive aquatic organisms. Nonetheless, the antibiotics presented no risk to consumer health. This study provides valuable insights for controlling antibiotic pollution in riverlake systems. [ABSTRACT FROM AUTHOR]

Cr3+ doped garnet‐type (A3B2C3O12) near‐infrared (NIR) phosphors is a desirable research hotspot due to their prospective night vision, bioimaging, and plant growth utilizations. Meanwhile, the origin of multisite broad emission is yet a controversial topic. To resolve the trouble, verifying accurately the multiple Cr3+ occupancy sites is a key. Furthermore, it is an urgent need for improving the external quantum efficiency and luminescent thermostability. Herein, in Y3Sc2Al3O12 (YSAO), advanced electron microscopy technique is employed to directly confirm that the obtained broadband NIR emission originates from Cr3+ in [ScO6] octahedral and [YO8] dodecahedral sites. The optimal YSAO:5%Cr3+ sample exhibits high quantum efficiency (IQE/EQE = 74/31%) and near‐zero thermal quenching (97%@423 K and 92%@473 K). The theoretical calculations and experimental proofs reveal that YSAO possesses high structural rigidity and wide bandgap, which is responsible for the extremely thermostable luminescence. The high‐power YSAO:5%Cr3+‐converted NIR LED device shows promising multifunctional applications. This work not only provides an efficient NIR broadband phosphor with near‐zero thermal quenching, but also provides an effective determination method for the multiple emitting centers of phosphor materials. [ABSTRACT FROM AUTHOR]

The effects of gold tailings and polyvinyl alcohol (PVA) fibre on the frost resistance of engineered cementitious composites (ECC) were investigated. The ECC were made with three gold tailings dosages and four PVA fibre contents. A water/binder (w/b) ratio of 0.28 was used for all mixtures. Surface damage, mass loss, relative dynamic elastic modulus, compressive strength and damaged layer thickness (DLT) were investigated to assess the frost resistance of the ECC. The results showed that the effect of gold tailings on the frost resistance of the ECC was marginal, but the frost resistance increased with an increase in PVA fibre content. The ECC with the addition of gold tailings had the same excellent frost resistance as those without gold tailings, indicating that it is feasible to replace silica sand with gold tailings at up to 100% replacement. A model to predict the DLT in ECC as a function of gold tailings dosage and freeze–thaw cycles was developed. [ABSTRACT FROM AUTHOR]

Drought-induced stress poses a significant challenge to wheat throughout its growth, underscoring the importance of identifying drought-stable quantitative trait loci (QTLs) for enhancing grain yield. Here, we evaluated 18 yield-related agronomic and physiological traits, along with their drought tolerance indices, in a recombinant inbred line population derived from the XC7 × XC21 cross. These evaluations were conducted under both non-stress and drought-stress conditions. Drought stress significantly reduced grain weight per spike and grain yield per plot. Genotyping the recombinant inbred line population using the wheat 90K single nucleotide polymorphism array resulted in the identification of 131 QTLs associated with the 18 traits. Drought stress also exerted negative impacts on grain formation and filling, directly leading to reductions in grain weight per spike and grain yield per plot. Among the identified QTLs, 43 were specifically associated with drought tolerance across the 18 traits, with 6 showing direct linkages to drought tolerance in wheat. These results provide valuable insights into the genetic mechanisms governing wheat growth and development, as well as the traits contributing to the drought tolerance index. Moreover, they serve as a theoretical foundation for the development of new wheat cultivars having exceptional drought tolerance and high yield potentials under both drought-prone and drought-free conditions. [ABSTRACT FROM AUTHOR]

The development of highly efficient rare earth-activated phosphor materials for solid-state lighting is restricted currently by concentration and temperature quenching behaviors. Herein, Eu3+-activated borotellurate Na2Y2TeO4(BO3)2 (NYTB) red-emitting phosphors are developed via a microwave-assisted method. The layered structure induces delayed concentration quenching (up to 50% Eu3+ activators), significantly contributing to highly efficient red emission with a luminescence efficiency of 83.7%. Meanwhile, the large energy barrier and sufficient structure rigidity of NYTB ensure low thermal quenching behavior. At 425 K, the red-emitting intensity only loses 6.3% of the original value at room temperature. Finally, a white light-emitting diode device is assembled with the NYTB:Eu3+, BaMgAl10O17:Eu2+, and (Ba,Sr)2SiO4:Eu2+ phosphors, exhibiting satisfactory lighting performance. This study not only deepens the insight of the layered structure-dependent concentration quenching delay, but also offers a thermally stable red phosphor candidate. [ABSTRACT FROM AUTHOR]