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This article is a book review of "French theories on text and discourse" by Ablali and Achard-Bayle. The book focuses on contemporary trends in French text and discourse studies, exploring the connection between text linguistics and discourse analysis. It also discusses the epistemology of text and various approaches to studying textual complexity and meaning. Additionally, the book examines the relationship between discourse analysis and other fields such as argumentation, society, and literature. Overall, the book offers a comprehensive understanding of text and discourse linguistics from a French perspective, challenging established paradigms and providing innovative perspectives. [Extracted from the article]

Active carbon materials were prepared by hydrothermal carbonization, KOH activation and vacuum calcination with the waste hemp stems as the raw material. And the effect of different carbon-alkali ratios on the morphology, microstructure, specific surface area and super-capacitive performances was also studied. When carbon-alkali ratios were 1:0, 1:1 and 1:2, the corresponding samples were marked as AC-0, AC-1 and AC-2, respectively. The results showed that with the decrease of carbon-alkali ratio, carbon material gradually changed from the irregular solid particles to the loose porous structure and the concentration of residual O-containing group increased. The specific surface area of AC-2 was 1 409.1 m² ⋅ g-1, larger than 709.5 m² ⋅ g-1 of AC-0 and 998.3 m² ⋅ g-1 of AC-1; correspondingly, the specific capacitance of AC-2 at 0. 5 A/g was 224. 6 F/g, much higher than 122. 7 F/g of AC-0 and 149. 2 F/g of AC-1; meanwhile, it also exhibited the fine cyclic performance. [ABSTRACT FROM AUTHOR]

Ba(Mg1/3Nb2/3)O3–MgO composite ceramics were prepared by solid-phase method. The ceramic exhibited the 1:2 ordered structure. By adding a proper amount of MgO, the permittivity decreased rapidly compared with other Ba(Mg1/3Nb2/3)O3-based ceramics. The Q × f values of the samples were greatly improved by nano-silica. Raman spectra showed that the permittivity and Q × f value showed a strong correlation with Raman shift and full width at half maximum of the A1g(O) phonon mode, respectively. The Raman shift of A1g(O) was consistent with the variation trend of permittivity. And the full width at half maximum of the A1g(O) phonon mode had a negative correlation with the Q × f value. The results showed that upon adding 1.5 wt% nano-silica to the ceramics, the ceramics sintered at 1550 °C for 5 h had the lowest Raman shift and the narrowest full width at half maximum, achieving the best microwave dielectric properties: εr = 22.22, Q × f = 80,436 GHz, τf = – 5.89 ppm/°C. [ABSTRACT FROM AUTHOR]

There is an urgent need to replace highly polluting pesticides with environmentally friendly green pesticides of high efficiency and low toxicity, because of the growing concern for quality and safety of agricultural products. To discover new pesticides with diverse chemical structures from natural products, a series of rhein derivatives 3a-9b were designed, synthesized, and evaluated for their antifungal activity and insecticidal activity. The bioassay showed that some compounds exhibited moderate antifungal activity against Rhizoctonia solani, but lower activity against the other five pathogens. Surprisingly, most compounds displayed potent insecticidal activity against Spodoptera litura and Tetranychus cinnabarinus at a concentration of 2 μmol/mL. In particular, compounds 3a, 5a and 3 b exhibited potent insecticidal activities against S. litura at 72 h, with mortality rates of 100%, 100% and 92.1%, respectively, which were equivalent to that of the insecticide fipronil (100%). Their structure-activity relationships were also discussed. The findings of this experiment provide helpful research ideas for the development of these rhein derivatives as novel natural product-based pesticides in crop protection. [ABSTRACT FROM AUTHOR]

According to the idea of the circular economy, various wastes should be reasonably managed and recycled for the achievement of the carbon peak and carbon neutralization (double carbon targets). For this purpose, Mn2+ in the waste graphene production effluent was firstly extracted in the form of Mn2O3 powder by the chemical precipitation and the subsequent calcination in air for the different times of 0.5 h, 2 h and 4 h, and the resultant samples were marked as Mn2O3-0.5 h, Mn2O3-2 h, Mn2O3-4 h, respectively. The removal rate and recovery rate of Mn2+ was calculated as about 99.9% and 92.6%, respectively. Furthermore, the effect of the calcination time on the morphology, structure and Li-storage performance of Mn2O3 powder was also further investigated. The results showed that the crystallinity of Mn2O3 increased with the increase of the calcination time, while the walnut-like morphology underwent a process from the integrity to the collapse. Resultantly, 2 h was an optimal calcination time, and Mn2O3-2 h powder exhibited a porous walnut-like morphology with the mean particle size of about 1.0 μm and the largest surface area. Furthermore, Mn2O3-2 h anode delivered the best electrochemical Li-storage performances. For example, the reversible discharge capacity of Mn2O3-2 h anode was about 466 mAh/g for 100 cycles at 1.0 A/g, higher than those of Mn2O3-0.5 h anode and Mn2O3-4 h anode. Obviously, such efforts provide a new strategy for the recovery of graphene production effluent, which may promote the development of the circular economy and the achievement of the double carbon targets. [ABSTRACT FROM AUTHOR]

The switch from the wastes to the electrode materials for lithium-ion batteries is desirable for the sustainable development. In this work, LiFePO4/C (LFP/C) were extracted from two wastes (expired ferrous gluconate, spent Li foils), and the positive role of vitamin C (VC) was also further investigated. The results showed that the morphology of LFP/C was spindle-like, and VC unified the particle size, slightly increased the carbon content, prevented from the oxidation of Fe (II), and inhibited the formation of insulator Li3PO4 phase, which were beneficial to improve the electronic conductivity and Li-storage performances of LFP/C cathode. For example, the corresponding reversible specific discharge capacity was 134.6 mAh·g−1 at 1.0 C for 400 cycles, higher than 123.2 mAh·g−1 of LFP/C cathode. No doubt, such efforts can reduce the accumulation of the wastes and facilitate to develop the circular economy mode. [ABSTRACT FROM AUTHOR]

BACKGROUND Tobacco sore shin caused by Rhizoctonia solani Kühn is a major soil‐borne fungal disease of tobacco, gradually causing infected stems to become thin and dry, leading to great losses to Chinaʼs tobacco industry. Fungicides with phloem mobility are needed for application to foliage to effectively control root or vascular system pathogens. In this study, phenazine‐1‐carboxylic acid‐valine conjugate (PCA‐Val) with strong phloem mobility was tested for control of tobacco sore shin. In vitro fungicidal activity, systemicity, and in vivo efficacy of PCA‐Val against R. solani in tobacco seedling were evaluated. RESULTS: In vitro fungicidal activity of PCA‐L‐Val against R. solani was lower than that of PCA or PCA‐D‐Val, but the in vivo protective activity and curative activity of PCA‐L‐Val was the highest among these chemicals tested. The systemicity tests in tobacco seedlings revealed that PCA did not possess phloem mobility, while PCA‐L‐Val and PCA‐D‐Val exhibited strong phloem mobility and could be transported and accumulated in the lower part of the seedling as well as throughout the phloem. In addition, we also found that, just like reported hormone amino acid conjugates, PCA‐L‐Val could be hydrolyzed by tobacco seedlings, to release free PCA. CONCLUSIONS: The current research results indicated that PCA‐L‐Val possess good phloem transport in tobacco and promising in vivo antifungal activity against R. solani, which can be used as a phloem‐mobile fungicide against tobacco sore shin in production practice. [ABSTRACT FROM AUTHOR]

The new technologies, such as soft open points (SOPs) and demand response (DR), offer original approaches to stabilize the system operation and accommodate the high penetration of distributed generators (DGs). However, the applied effects of these technologies are closely affected by the uncertainties of the consumer's willingness and the outputs of DGs. To solve the problems caused by the uncertainty of the resources in active distribution system, this paper proposes a distributionally robust co‐optimization model for the demand side resources and SOPs, which realizes the combination of investment economy and operation robustness. Next, using equivalent substitution and polyhedron linearization technique, this paper proposes the mathematical method which transforms the original non‐linear programming model into a mixed‐integer linear programming model, and obtains the solution to the distributionally robust model with column and constraint generation (CCG) algorithm. Finally, the effectiveness of the proposed model is verified with the sample from a power distribution system in northern China. The result demonstrates that the co‐optimization model can realize complementary advantages of the demand side resources and SOPs, which can not only guarantee the economy of scheme, but also improve the accommodation of DGs. [ABSTRACT FROM AUTHOR]

To develop new phenazine carboxylic acid derivatives with better phloem mobility, five novel 7-amino acid substituted phenazine-1-carboxylic acids were synthesised by introducing amino acids into PCA at the 7-position. The phloem mobility experiments in Ricinus communis seedlings showed that retaining the carboxyl group of PCA and conjugating amino acids to its phenazine ring can also endow PCA with phloem mobility. Comparing our previous research, we found the amino acids substituted at 7-position on phenazine ring of PCA could clearly enhance the phloem mobility of PCA than that of amino acids conjugated with carboxyl group. Especially, the phloem transport concentration of the compound 7-L-isoleucine substituted PCA (7d) was 21 times higher than PCA-L-isoleucine conjugate (8d). These data suggest that the introduction of amino acids at different structural sites on the phenazine ring could effectively enhance the phloem mobility of PCA and it is worth a further study. [ABSTRACT FROM AUTHOR]

CaO-B2O3-SiO2 (CBS) glass ceramic with various glass network modifiers were synthesized to develop a kind of material sintered at low temperature for multi-layer ceramic substrates. The influence of double alkali metal oxides (Na2O and K2O) on sintering characteristics, microstructures and dielectric properties of CBS glass ceramic were investigated. XRD analysis showed that the major crystalline phase was β-CaSiO3 and CaB2O4, and the strength of the peak increased with the addition of network modifiers. DSC curve revealed that the process of crystallization and softening were obviously affected. SEM photographs exhibited that the microstructures were composed of amorphous phases, pores and crystalline phases. FTIR showed that the additives changed the continuity of CBS glass structure. An appropriate amount of Na2O and K2O additives could significantly improve the sintering characteristics and dielectric properties. CBS samples with 1.5 wt% (Na2O + K2O) sintered at 850 °C for 15 min presented the best performances with the bulk density of 2.53 g/cm3, εr = 5.94 and tanδ = 1.22 × 10−3 at 10 GHz. [ABSTRACT FROM AUTHOR]