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The magnetic properties, magneto‐resistivity, Hall resistivity, Seebeck coefficient, and heat capacity are investigated for a magnetic topological nodal‐line semimetal TbSbTe. The calculated energy‐band structures of TbSbTe show two nodal rings on the kx‐ky planes, and the Fermi surface possesses one electron pocket with an enclosure of one hole pocket around the Γ point. The multiple magnetic phase transitions are induced at critical magnetic fields of Hc1 ≈ 10.5 kOe, Hc2 ≈ 20.8 kOe, and Hc3 ≈ 38.2 kOe at 2 K for the H // ab plane. Temperature dependence of electrical resistivity displays a hump‐like feature around 240 K, a general positive slope above TN = 6 K but a negative slope below TN. The magnetoresistance exhibits a conversion from the semi‐classical H2 dependence at weak fields to the linear‐field dependence at high fields, indicating the presence of a Dirac linear energy dispersion. TbSbTe may provide an ideal platform for studying topological physics and designing devices based on topological quantum materials. [ABSTRACT FROM AUTHOR]

Five types of drying methods were demonstrated to dry corn silks and their effects on the constitution of phenolic and antioxidant capacities were analyzed, so as to identify the best method to preserve the quality factors of corn silk including phenolic, flavonoid, and antioxidant activity. According to the results, drying can improve the level of phenolic and flavonoid in corn silk by 2.5–3.2 folds and 1.6–3.6 folds, respectively. Drying in shade (MCS‐shade) had the highest content of total phenolics and flavonoids. Eight kinds of phenolic were detected by HPLC and ferulic acid was the main component. MCS‐shade also showed the highest PSC value and CAA value (no wash). Overall, MCS‐shade (silks treated by shade‐drying) showed the best performance and the quality of dry corn silks affected greatly by different drying methods. Novelty Impact Statement: This paper showed that drying methods can greatly improve the levels of phenolic and flavonoid. Shade‐drying had the best results with higher phenolic and antioxidant activity. Light may cause stress signals and increase the contents of bound flavonoid. [ABSTRACT FROM AUTHOR]

BACKGROUND Free fractions of different blackberry varieties' extracts are high in phenolic compounds with antioxidant activities. However, the phenolic profiles and antioxidant activities against peroxyl radicals of bound fractions of different blackberry varieties' extracts have not been previously reported. In addition, what the key antioxidant phenolic compounds are in free and bound fractions of blackberry extracts remain unknown. This study aimed to investigate the phenolic profiles and antioxidant activities of free and bound fractions of eight blackberry varieties' extracts and reveal the key antioxidant phenolic compounds by boosted regression trees. RESULTS: Fifteen phenolics (three anthocyanins, four flavonols, three phenolic acids, two proanthocyanidins, and three ellagitannins) were identified in blackberry by ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry. Ferulic acid, ellagic acid, procyanidin C1, kaempferol‐O‐hexoside, ellagitannins hex, and gallic acid were major bound phenolics. Bound fractions of eight blackberry varieties' extracts were high in phenolics and showed great antioxidant activity. Boosted regression trees analysis showed that cyanidin‐3‐O‐glucoside and chlorogenic acid were the most significant compounds, contributing 48.4% and 15.9% respectively to the antioxidant activity of free fraction. Ferulic acid was the most significant antioxidant compound in bound fraction, with a contribution of 61.5%. Principal component analysis showed that Kiowa was the best among the eight varieties due to its phenolic profile and antioxidant activity. CONCLUSION: It was concluded that blackberry varieties contained high amounts of bound phenolics, which confer health benefits through reducing oxidative stress. Ferulic acid was the key compound to explain the antioxidant activities of bound fractions. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Temperature distribution in concrete is significant to the concrete structure's macro properties and different factors affect the heat transfer in concrete, and therefore influence the temperature distribution. This work established a three-dimensional transient heat transfer model coupled with various environmental factors, using the finite element method for calculating the results and real-measured data for testing accuracy. In addition, a sensitivity evaluation of various factors was conducted. Due to various environmental factors, the results revealed that the prediction of temperature distribution in concrete by the three-dimensional model had great accuracy with an error of less than 4%. A particular hysteresis effect of temperature response in the concrete existed. Considering heat transfer in different spatial directions, the model can predict the temperature change of each spatial point instead of the spatial surface in different depths, proving the shortcomings of a one-dimensional heat transfer model. A greater solar radiation intensity caused a more significant temperature difference on the concrete surface: the surface temperature difference in July was twice as significant as that in December. Wind speed had a cooling effect on the concrete surface, and stronger wind speed accompanied with a stronger cooling effect made the surface temperature closer to the ambient temperature. Material properties had different effects on the temperature distribution of the surface part and internal part: the specific heat capacity determined the speed of the outer layer temperature change while the thermal conductivity determined the speed of the inner layer temperature change. [ABSTRACT FROM AUTHOR]

This study aims to evaluate phenolics, flavonoids, total and cellular antioxidant activity (CAA), antioxidant capacity in ear sections of sweet corn. Corn cob and mature corn silk showed the highest contents of total phenolics and flavonoids (p < 0.05), respectively. Gallic acid and ferulic acid were the main free and bound phenolics in each ear part of corn, respectively (p < 0.05). Corn resident (CR) had a dominant role in total antioxidant activity and cellular antioxidant activity (CAA) (p < 0.05). Considering all the antioxidant properties, CR showed the best performance. The content of ferulic acid was correlated closely with CAA (R2 = 0.898, p < 0.05) and total antioxidant capacity (R2 = 0.971, p < 0.05), and total antioxidant capacity was also connected tightly with total phenolics (R2 = 0.886, p < 0.05). The results of this investigation were significant to enhance recognition and application of ear sections in food industry. Practical applications: Sweet corn is widely cultivated in Asia, America, and other regions for fresh or industrial food because of high sugar, dietary fiber, and vitamins. However, there is no systematic assay on ear sections of sweet corn concerning antioxidant evaluation. The study investigated phytochemical profiles and antioxidant capacity in ear sections of sweet corn systematically, and made a comprehensive comparison of them combined with correlation analysis. The results indicated that ear sections of sweet corn, not only kernels, demonstrated high antioxidant capacity. Ear sections show promising potential application in food industry. [ABSTRACT FROM AUTHOR]

To illustrate the impact of molecular structure, especially heterocycle unit, on the sensing performance, two kinds of π-conjugated molecules containing aromatic heterocyclic (Dye 1) and aromatic ring (Dye 2) were identified and compared each other. Even with similar structures, they possessed quite different spectral and colorimetric responses to F−, Cl−, Br−, I−, NO 3 −, HSO 4 −, H 2 PO 4 −, ClO 4 − and CH 3 COO−, etc. The reason might result from the difference in withdraw-electron ability of aromatic and heterocyclic rings, which would lead to different acidity of active H in the target π-conjugated molecules. In acidic aqueous, Dye 1 expressed a reversible ratiometric-colorimetric response to F−, accompanying with a visual color change from bright yellow to purple, a nice linear range of 2.0–35.0 × 10−6 mol/L and a low detection limit of 1.60 × 10−7 mol/L. While Dye 2 did not react with any anion due to its weak acidity of active hydrogen. Under the optimized conditions, Dye 1 was successfully applied for colorimetric or naked-eye detection of F− in environmental water, tea and toothpaste samples with RSD ≤ 3.1%. The recognition mechanism for Dye 1 to F− was confirmed to be deprotonation one with a 1:1 binding stoichiometry. Two kinds of π-conjugated molecules containing aromatic heterocyclic (Dye 1) and aromatic ring (Dye 2) were identified and compared. With introduce of aromatic heterocycle, Dye 1 possessed more excellent sensing property to F−, such as improved selectivity, sensitivity and reversibility, especially applicability in aqueous owing to the increasing acidity of active hydrogen atoms by deprotonation recognition mechanism. Unlabelled Image • Two kinds of π-conjugated molecules containing heterocycle unit or not were compared. • Dye 1 with heterocycle is a potentially reversible ratiometric-colorimetric sensor of F−. • Dye 1 was successfully applied for colorimetric or naked-eye F− detection in environmental water, tea and toothpaste. • The sensing mechanism was confirmed to be deprotonation one with a 1:1 binding stoichiometry. [ABSTRACT FROM AUTHOR]