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• A soy protein-based adhesive was synthesized via adding a tailor-made crosslinker. • The crosslinker with multiple epoxy groups was designed without solvent or catalyst. • The adhesives with superior bonding strength and water resistance was prepared. The weak bonding strength and poor water resistance of soy protein-based adhesive have limited its application as a non-formaldehyde adhesive in wood manufacturing industry. In this work, a novel soy protein-based adhesive was prepared by introducing a tailor-made crosslinker with multiple epoxy groups and flexible long chains without any solvent or catalyst via a one-pot strategy. The multiple epoxy groups could react with the hydrophilic groups (hydroxyl and amino) on the soy protein molecules to construct densely crosslinking networks, which was proved by the sol–gel results. The crosslinking networks were beneficial to enhancing the bonding strength and water resistance of the adhesive. Consequently, the dry bonding strength and the wet bonding strength were increased from 1.11 MPa and 0.22 MPa to 2.79 MPa and 1.12 MPa, respectively, marking increments of 151% and 409% when compared to the pristine soy protein-based adhesive. The bonding strength was beyond the standard of type II plywood (≥0.7 MPa, GB/T17657 − 2013). Furthermore, the flexible long chains of the crosslinker was also conductive to improving the toughness of the adhesive. Therefore, this work may open a feasible way to produce non-formaldehyde adhesives with superior bonding strength and water resistance, and thus broadening the application of soy protein. [ABSTRACT FROM AUTHOR]

The super-chondritic Mo isotopic composition of the continental crust has been attributed to contributions from subducted oceanic slabs and/or sediments, which introduce isotopically light Mo to the mantle. It has been hypothesized that dehydrated oceanic slabs subduct into the deep mantle and contribute to the genesis of ocean island basalts (OIBs). However, OIBs have similar average δ98/95Mo values (−0.22‰± 0.04‰; 2SE; n = 87) to the depleted mantle. Subducted oceanic sediments may create a light-δ98/95Mo reservoir in the subcontinental lithospheric mantle, but this has not been investigated in detail. Understanding the Mo isotopic systematics of the continental crust and mantle requires an understanding of the Mo isotopic composition of lithospheric mantle-derived volcanic rocks. The lithosphere in the Tibetan region has experienced multiple stages of oceanic subduction and is thus ideal for studying magmas derived from sediment-modified lithospheric mantle. Mafic ultrapotassic volcanic rocks (UPVRs) from the Sailipu area on the southern Tibetan Plateau have high Mg# values (67.1–72.5) and enriched Sr–Nd isotopic compositions and are primitive magmas derived from the lithospheric mantle. These rocks have higher Ce/Mo ratios (225–422) and lighter δ98/95Mo values (−0.45‰ to −0.13‰) than the depleted mantle, mid-ocean ridge basalts (MORBs), and OIBs, as well as high ε Hf (t) values at given ε Nd (t) values compared with the terrestrial array (Δε Hf = 4.59–5.73). The involvement of Ca-poor pelagic sediments rather than the lower continental crust and hydrated oceanic slab best accounts for the high Ce/Mo ratios and light δ98/95Mo values of the studied rocks. The Sailipu UPVRs also have higher Nb/Ta (18.9–20.8) and Th/La (2.6–3.4) ratios than arc-related igneous rocks and MORBs, suggesting that their source was phlogopite-bearing lithospheric mantle with a metasomatic vein component (rutile + monazite ± lawsonite). We propose a two-stage geodynamic process to explain the formation of the Sailipu UPVRs: (1) a metasomatic vein component with high Th/La and Ce/Mo ratios formed in the lithospheric mantle during multiple stages of oceanic subduction; (2) high mantle temperatures related to convective thinning of the lithosphere resulted in melting of the vein component and the ambient mantle, which produced hybrid melts of various mantle domains during the post-orogenic stage. The Sailipu UPVRs have enriched Sr–Nd isotopic compositions and high Th/La and Ce/Mo ratios, similar to lamproites that are widespread in the Tethyan orogenic realm from the Mediterranean to the southern Tibetan Plateau. Given that UPVRs with light δ98/95Mo values have also been identified in the Western Alps, we propose that the isotopically light Mo component is widespread in Tethyan lithospheric mantle. This isotopically light Mo in the lithospheric mantle may be a complementary end-member to the isotopically heavier continental crust. The recycling of subducted oceanic sediments has a key role in the deep recycling of Mo. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Beila and Dongga granites emplaced at ca. 118 Ma and 110 Ma, respectively. • The formation of the Beila granites was in response to the Lhasa-Qiangtang collision. • The Dongga granites resulted from the breakoff of the Bangong-Nujiang oceanic slab. • The locally survived ancient basement beneath the northern Lhasa Terrane has affinity of that in the central Lhasa Terrane. Collisional orogenic belts serve as excellent places for investigating geodynamic process and growth mechanism of the continental crust. As one of the largest collisional orogenic belts worldwide, the Tibetan Plateau is formed by the amalgamation of multiple tectonic terranes. However, the nature and composition of the crustal basement beneath the northern Lhasa Terrane, located in central Tibetan Plateau, is still a matter of debate. Here, we investigated a series of Early Cretaceous granites in the Beila and Dongga areas, northern Lhasa Terrane. Zircon U-Pb dating reveals that the Beila and Dongga granites were emplaced at ca. 118 Ma and 110 Ma, respectively. These granites are characterized by high SiO 2 and K 2 O, low TiO 2 and P 2 O 5 contents and low Mg#. They exhibit enrichment in light rare earth elements, significant negative Eu anomalies, and depletion in Ba and Sr. These geochemical features suggest that they belong to highly fractionated I-type granites. Both the Beila and Dongga granites display similar and enriched whole-rock Sr-Nd and zircon Hf isotope compositions, implying a likely common ancient crustal origin. Given the temporal sequences and redox conditions during their formation, it is highly probable that the Beila and Dongga granites formed during the syn-collision stage between the Lhasa and Qiangtang Terranes and the breakoff of the Bangong-Nujiang oceanic slab, respectively. Integrated with coeval magmatism in the central Tibetan Plateau, our new data reveal the presence of a regionally preserved ancient basement beneath the northern Lhasa Terrane, analogous to the equivalent basement beneath the central Lhasa Terrane. [ABSTRACT FROM AUTHOR]

[Display omitted] • Early trachyandesites and rhyolite in the Gangshan area were derived from the lower continental crust. • Early Cretaceous intermediate-felsic rocks across the northern NCC have ages following a younging trend towards southeast. • Early Cretaceous Paleo-Pacific slab rollback triggered the large-scale magmatism in the northern NCC. Extensively developed Early Cretaceous intermediate-felsic rocks in the northern North China Craton (NCC), offer an opportunity to unravel the nature of Paleo-Pacific subduction and associated geodynamic processes by investigating their spatio-temporal characteristics and petrogenesis. Here we present geochemical and geochronological results of Early Cretaceous (118–115 Ma) trachyandesites and rhyolites from the eastern Hebei, northern NCC. The trachyandesites show low MgO (0.74–2.65 wt%) and Mg# (17–38), as well as enriched whole-rock Nd-Hf isotopic compositions (ε Nd (t) = -17.1 to -13.3, ε Hf (t) = -12.9 to -10.8), suggesting a probable origin of the enriched mafic lower crust. They also exhibit relative enrichment in LREE and flat in HREE. Trace element geochemical modeling results indicate that the trachyandesites likely formed through partial melting of the mafic lower crust at 790–820 °C and ca. 10 kbar (30–33 km). The rhyolites, characterized by higher SiO 2 contents and similar ε Nd (t) (-17.4 to -15.5) and zircon ε Hf (t) values (-14.4 to -7.6) compared to the trachyandesites, probably represent the magmatic derivates of the trachyandesites. MELTS modeling results suggest that the rhyolites likely formed through fractional crystallization of the trachyandesitic magmas at ∼ 775 °C and 1–3 kbar. Integrating with previous studies, our study confirms that the Early Cretaceous intermediate-felsic magmatism across the northern NCC became younger from northwest to southeast. We propose that the change of the migration direction of these Early Cretaceous intermediate-felsic rocks is primarily attributed to slab rollback of the subducting Paleo-Pacific Plate. [ABSTRACT FROM AUTHOR]