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The interaction between geosynthetics and soil is vital for the stability and the bearing capacity of geosynthetic-reinforced soil structures. This contact behavior between geosynthetics and granular soils has been extensively studied in the literature while there is scarcity of it related to geosynthetics and cohesive soils particularly with softening responses. This paper presents a strain-softening model of geobelt-clay interaction based on direct shear test results under two compaction degrees. A theoretical model for evaluating the pullout behavior of a geobelt is proposed by employing the strain-softening model verified by direct shear tests and a hyperbolic model capturing the stress-strain curves of a geobelt calibrated by uniaxial tensile tests. The proposed model is numerically solved and validated by pullout tests. A kind of sensor-enabled geobelt (SEGB) was adopted in all the aforementioned tests. Both test and numerical results show an overall softening trend in terms of front pull-out force versus displacement. Generally, the model proposed can give reasonably good agreement between calculations and test data during the whole pull-out range. Also, the strain distributions measured by SEGBs demonstrate the working process during the pullout tests, which makes SEGBs a potentially new choice for the strain measurements of in-soil geobelts. Key words: strain-softening model, geobelt-clay interaction, pullout test, sensor-enabled geobelts, numerical solution. L'interaction entre les geosynthetiques et le sol est vitale pour la stabilite et la capacite portante des structures de sol renforce de geosynthetiques. Ce comportement de contact entre les geosynthetiques et les sols granulaires a fait l'objet d'etudes approfondies dans la litterature, alors qu'il y a absence d'etudes liees aux geosynthetiques et sols cohesifs, en particulier aux reponses d'adoucissement. Cet article presente un modele d'adoucissement de la deformation de l'interaction <>-argile (ou geobelt est une bandelette geotextile) base sur les resultats d'essais de cisaillement direct sous deux degres de compactage. Un modele theorique devaluation du comportement a l'arrachement de la bandelette geotextile est propose en utilisant le modele d'adoucissement de la contrainte verifie par des essais de cisaillement direct et un modele hyperbolique capturant les courbes contrainte-deformation de la bandelette geotextile calibrees par des essais de traction uniaxiale. Le modele propose est resolu numeriquement et valide par des essais d'arrachement. Une sorte de bandelette geotextile a capteurs (<< SEGB >>) a ete adoptee dans tous les essais susmentionnes. Les resultats des essais et les resultats numeriques montrent une tendance generale a la baisse de la force d'arrachement avant en fonction du deplacement. En general, le modele propose peut donner une assez bonne concordance entre les calculs et les donnees d'essai pour l'ensemble de la plage d'arrachement. De plus, les distributions de deformation mesurees par SEGB demontrent le processus de travail pendant les essais d'arrachement, ce qui fait de SEGB un choix potentiellement nouveau pour les mesures de deformation des bandelettes geotextiles dans le sol. [Traduit par la Redaction] Mots-cles: modele d'adoucissement de la deformation, interaction<>(bandelette geotextile)-argile, essai d'arrachement, bandelettes geotextiles equipees de capteurs, solution numerique., Introduction In recent years, geosynthetics have been extensively employed in geotechnical engineering practice to reinforce soils and improve the overall performance of foundations (Chen and Abu-Farsakh 2016; Shahin et al. [...]

A new two-step, one-pot synthesis of benzo[f][1,2]thiazepine 1,1-dioxides was developed, which contains a visible-light mediated aza Paternò–Büchi reaction of benzo[d]isothiazole 1,1-dioxides with alkenes and a Lewis acid catalyzed ring-expansion of azetidine. In this work, the mechanism of the aza Paternò–Büchi reaction was also investigated. [ABSTRACT FROM AUTHOR]

A Sc(OTf)3 catalyzed intramolecular cyclization reaction of 2-alkyl-1,4-benzoquinone derived from D–A cyclopropane was discovered. This reaction involves single-electron transfer, proton-transfer, an aromatization driven spin center shift, and radical coupling processes, and offers an efficient method for the synthesis of 6-chromanols from D–A cyclopropanes. [ABSTRACT FROM AUTHOR]

Developing luminescent radicals with tunable emission is a challenging task due to the limitation of alternative skeletons. Herein, a series of carbene‐triphenylamine hybrids were prepared by the direct C2‐arylation of N‐heterocyclic carbenes with 4‐bromo‐N,N‐bis(4‐methoxyphenyl)aniline. These hybrids showed multiple redox‐active properties and could be converted to carbon‐centered luminescent radicals with blue‐to‐cyan emissions (λmax: 436–486 nm) or nitrogen‐centered luminescent radicals with orange emissions (λmax: 590–623 nm) through chemical reduction or oxidation, respectively. The radical species were characterized by electron paramagnetic resonance spectroscopy, ultraviolet‐visible spectroscopy, and single‐crystal X‐ray diffractometry analysis. Notably, the corresponding nitrogen‐centered radicals exhibited good stability in atmospheric air, and their thermal decomposition temperatures were determined to be above 200 °C. In addition, spectral and theoretical calculations indicate that all radicals exhibit anti‐Kasha emissions. [ABSTRACT FROM AUTHOR]