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The sub-continental lithosphere mantle (SCLM) contains considerable amounts of carbon and is responsible for significant CO 2 emissions via magmatism during major heating and rifting events. However, the role of SCLM in Earth's carbon cycle during other geological processes, such as decratonization, a process of major removal and replacement of cratonic SCLM, remains poorly understood. The North China Craton is an archetype of Archean craton having been decratonized during the Mesozoic with extensive magmatism developed. Here we show that the primary melt of Early Cretaceous Yixian basalts contained abundant CO 2 (0.6 wt%), through investigating melt inclusions trapped in olivine crystals. The melt inclusions are alkalic and chemically distinct from their sub-alkalic host basalts, which could be explained by that the primary alkalic melt was reactively modified during magma ascent in the SCLM. The primary melt has geochemical characteristics consistent with partial melting of a veined carbon-rich amphibole clinopyroxenite source in the SCLM formed metasomatically during circum-craton subduction events. The findings highlight that the carbon introduced into the cratonic SCLM during subduction could be subsequently reactivated and transferred to the crust and atmosphere through decratonization-related magmatism, which might represent a major process regarding the SCLM in regulating the terrestrial carbon cycle. • CO 2 in decratonization-related magma is measured utilizing melt inclusions; • The primary magma contains abundant CO 2 (∼0.6 wt%) and was reactively modified; • A carbon-rich veined metasomatic source in the SCLM is responsible for the magma; • Decratonization acts as a potential process for remobilizing carbon in the SCLM. [ABSTRACT FROM AUTHOR]

The oxygen fugacity (f O 2) of the Earth's mantle is a key parameter that regulates fundamental geological processes such as planetary differentiation, mantle melting, and volatile cycling. Large igneous provinces (LIPs) are among the most voluminous mafic volcanic eruptions in the Earth's history. Constraining the f O 2 of LIP rocks is critical for understanding the redox state of the mantle and migration of volatiles from the deep Earth to the atmosphere. Here, we investigated primitive picrites from the Dali and Lijiang areas belonging to the Emeishan LIP, which contain early-crystallized olivine phenocrysts with Fo contents up to 93.5 and 91.9, respectively. The f O 2 conditions of primary and derivative melts are determined by the olivine-spinel and olivine-melt V oxybarometers, aided by temperature estimates from olivine-spinel Al and olivine-melt Sc/Y thermometers. The calculated f O 2 values are negatively correlated with olivine Fo contents due to fractionation of mafic minerals in a system closed to oxygen. The f O 2 s of Dali and Lijiang primary melts are −0.8 ± 0.4 and + 0.6 ± 0.3 (1σ) ΔFMQ log units, respectively, more variable than those of primitive MORBs, indicating significant f O 2 fluctuations in primary magmas from the Emeishan LIP caused by changes in both redox state of the source rock and depth of melt extraction. Melt barometer constrains the Dali and Lijiang primary melts generated at 4.7 and 3.0 GPa, respectively. After correcting for the depth effect, the Dali and Lijiang sources are more oxidized (with higher Fe3+/∑Fe ratios), in varying degrees, than the ambient upper mantle, likely due to incorporation of recycled surface materials. Under such oxidized conditions, mantle carbon is efficiently extracted during melting in the form of CO 2 and released to the atmosphere during massive magma emplacement, which may have played an important role in causing the climatic and environmental changes and triggering the end-Guadalupian mass extinction. [ABSTRACT FROM AUTHOR]

We introduce unitary-gate randomized benchmarking (URB) for qudit gates by extending single- and multi-qubit URB to single- and multi-qudit gates. Specifically, we develop a qudit URB procedure that exploits unitary 2-designs. Furthermore, we show that our URB procedure is not simply extracted from the multi-qubit case by equating qudit URB to URB of the symmetric multi-qubit subspace. Our qudit URB is elucidated by using pseudocode, which facilitates incorporating into benchmarking applications. [ABSTRACT FROM AUTHOR]

Picrites are potentially near‐primary melts that offer rare insights into the earliest stages of magmatic evolution. However, without detailed investigation of magmatic processes, robust records of early melt evolution and mantle melting behavior cannot be acquired. Here petrological and geochemical interrogations of the Dali picrites were conducted to investigate the magmatic processes. Compositional variation observed in the Dali picrites is dominated by variable accumulation of a wehrlitic assemblage, transported by a low MgO carrier melt. Groundmass clinopyroxenes were produced by direct crystallization of the carrier melt. In contrast, compositions of olivine‐hosted melt inclusions and clinopyroxene macrocrysts indicate that olivine and clinopyroxene macrocrysts crystallized from diverse melt batches that are genetically related to the carrier melt, which formed as a consequence of magma mixing. The compositional range of melts in equilibrium with clinopyroxene macrocrysts with Mg# < 88 (> 88) is similar to (notably smaller than) the range of melt inclusions hosted in olivine macrocrysts with equivalent forsterite values. This observation can be explained by coupling between major and trace elements during partial melting in the mantle. Overall, a process involving periodic magma replenishment, tapping, and fractional crystallization in deep magma chamber(s) can explain the compositional variations recorded in the Dali macrocryst assemblage. Close genetic relationships between macrocrysts and carrier melts appear to be common to many primitive mafic rocks, which may reflect common deep magma chamber processes whereby diverse mantle‐derived melts are injected and evolved, and the primitive macrocrysts thus formed are subsequently transported by mixed liquids, producing macrocryst‐bearing primitive mafic rocks. Key Points: Compositional variation in the Dali picrites is dominated by variable accumulation of olivine and clinopyroxene macrocrystsThe macrocrysts crystallized from multiple parental magmas and are genetically related to the carrier meltPeriodic RTX processes in the magma chamber(s) dominate the compositional evolution of the diverse parental melts [ABSTRACT FROM AUTHOR]

Olivine-hosted melt inclusions within lava retain important information regarding the lava’s primary magma compositions and mantle sources. Thus, they can be used to infer the nature of the mantle sources of large igneous provinces, which is still not well known and of the subject of debate. We have analysed the chemical compositions and Pb isotopic ratios of olivine-hosted melt inclusions in the Dali picrites, Emeishan Large Igneous Province (LIP), SW China. These are the first in-situ Pb isotope data measured for melt inclusions found in the Emeishan picrites and allow new constraints to be placed on the source lithology of the Emeishan LIP. The melt inclusions show chemical compositional variations, spanning low-, intermediate- and high-Ti compositions, while their host whole rocks are restricted to the intermediate-Ti compositions. Together with the relatively constant Pb isotope ratios of the melt inclusions, the compositional variations suggest that the low-, intermediate- and high-Ti melts were derived from compositionally similar sources. The geochemical characteristics of melt inclusions, their host olivines, and whole-rocks from the Emeishan LIP indicate that Ca, Al, Mn, Yb, and Lu behave compatibly, and Ti, Rb, Sr, Zr, and Nb behave incompatibly during partial melting, requiring a pyroxenite source for the Emeishin LIP. The wide range of Ti contents in the melt inclusions and whole-rocks of the Emeishan basalts reflects different degrees of partial melting in the pyroxenite source at different depths in the melting column. The Pb isotope compositions of the melt inclusions and the OIB-like trace element compositions of the Emeishan basalts imply that mixing of a recycled ancient oceanic crust (EM1-like) component with a peridotite component from the lower mantle (FOZO-like component) could have underwent solid-state reaction, producing a secondary pyroxenite source that was subsequently partially melted to form the basalts. This new model of pyroxenite melting could explain the geochemical variations among the low-, intermediate- and high-Ti basalts for the Emeishan LIP and challenges the prevailing belief that the source of the Emeishan basalts is peridotite. [ABSTRACT FROM AUTHOR]

An integrated study of zircon U-Pb ages and Hf-O isotopes, whole rock and apatite geochemistry, and whole rock Sr-Nd-Hf isotopes were conducted for the Jurassic adakitic volcanic rocks from the Tiaojishan Formation in the Yanshan Fold and Thrust Belt (YFTB) of the North China Craton, to investigate their genesis, with attention to the role of crust thickness in achieving the adakitic traits. Zircon U-Pb dating gives eruption ages of 162–158 Ma for these rocks. These rocks have variable SiO 2 (55.7–68.1 wt%) and MgO (0.35–4.0 wt%), and adakitic trace element signatures including high Sr/Y (27.9–100) and (La/Yb) N ratios (9.6–27.6). Chemical variations in whole rock and apatite suggest a feldspar-dominated fractional crystallization, superimposed by variable mineral accumulation on whole rock compositions. Together with isotopic compositions that include evolved whole rock (87Sr/86Sr) i = 0.70447–0.70591, ε Nd (t) = −17.5 to −12.1, and ε Hf (t) = −22.2 to −11.2, and zircon ε Hf (t) = −26.8 to −11.2 and δ18O = 5.7–7.0 ‰, we attribute these rocks are sourced from mafic lower continental crust. By comparing the trace element signatures between the examined samples and modern continental arc magmatic rocks formed at variable crustal thickness, it is suggested that these rocks are most likely originated from a thickened crust. A further estimate based on whole rock Sr/Y and La/Yb gives a crust thickness of 56 ± 7 km. The crust thickening and associated uplift of the YFTB could be attributed to the westward subduction of the Paleo-Pacific plate. This led to a high altitude (∼3.8 ± 0.9 km) and cool climate habitat (a mean annual paleotemperature of 7 ± 7 °C) for the Yanliao Biota lived therein during this period, which may have played an important role in the earliest appearance of the feathered characteristic of dinosaurs. • A thickened lower continental crust source is responsible for the volcanic rocks. • Crust thickening and uplift are related to the subduction of the Paleo-Pacific plate. • Uplift-induced cooling may be important for the appearance of feathered dinosaurs. [ABSTRACT FROM AUTHOR]

An efficient and simple method for the transamidation of carboxamides, phthalimide, ureas and thioamide with amines catalyzed by commercially available benzoic acid under metal-free conditions is described. Furthermore, to the best of our knowledge, this is the first report about the transamidation of an aromatic thioamide with amines. [ABSTRACT FROM AUTHOR]

We present new whole rock major and trace element and, Sr–Nd–Hf isotope data for Mesozoic basalts and andesites from the Siziwangqi area, northwestern China, in order to constrain their petrogenesis and regional tectonic implications. The basalts belong to the shoshonitic series and can be subdivided into olivine (Ol-) and plagioclase (Pl-)basalts. The Ol-basalts have moderate MgO contents (5.1–5.5 wt%) and Mg# values (48.7–50.3), and trace element patterns similar to typical ocean island basalts with positive Nb–Ta and negative Pb anomalies. We interpret the Ol-basalts as mantle-derived rocks. The Pl-basalts and andesites are more differentiated than the Ol-basalts, and have low MgO contents (3.9–4.5 and 0.55–3.4 wt%, respectively) and Mg# values (40.3–43.3 and 26.9–47.4; respectively). Trace element (e.g., low Nb/U and Ce/Pb ratios) and Sr–Nd–Hf isotope data for the Pl-basalts and andesites indicate an origin by fractionation and mixing between the mantle-derived magma parental to the Ol-basalts and a crust-derived silicic magma. Crustal melting was induced by the underplating of the mafic parental magmas of the Ol-basalts. Geochemical features of the Ol-basalts, including high SiO 2 , Nb, Ta, Na 2 O/K 2 O, and Fe/Mn and low Rb/Sr and Dy/Yb, are best explained by the vein-plus-wall rock melting of a metasomatized mantle source consisting of amphibole–clinopyroxene-rich veins and surrounding peridotites. The Ol-basalts have enriched Sr–Nd isotopic compositions ((87Sr/86Sr) i = 0.70585–0.70597; ε Nd (t) = −2.8 to −2.6) and decoupled Hf–Nd isotopes with positive ∆ε Hf (t) (+4.5 to +5.0) that are consistent with recent enrichment of the lithosphere by subduction components from the Paleo-Asian oceanic slab. We propose that the Siziwangqi magmatism was related to intra-continental extension of the North China Craton. • New whole rock geochemical data for the Siziwangqi volcanic rocks, western NCC. • Geochemical variations of the rocks caused by magma mixing and fractionation. • A vein-plus-wall rock melting model for the genesis of olivine-basalts. • The Siziwangqi magmatism related to intra-continental extension in the NCC. [ABSTRACT FROM AUTHOR]

In this paper, the unsteady characteristics of tip leakage flow in axial fans with circumferential skewed blades were investigated at off-design conditions using wall pressure test. The static pressure fluctuations near blade tip were captured at off-design conditions by using pressure sensors mounted on casing wall. From the measured results, instantaneous characteristics of tip leakage flow in circumferential skewed fans were analyzed. Based on the measurement results, as the flow rate decreases, the broadband frequency components of tip leakage flow tend to increase in the low frequency domain. The forward-skewed blade is found to be effective in controlling tip leakage flow to expand from blade leading edge to tail edge, the TLF component of the BSK rotor propagates more fast than that of FSK rotor. The instability of tip leakage flow under off-design conditions is controlled by circumferential skewed blades. [ABSTRACT FROM AUTHOR]

This paper used numerical methods to investigate the flow field around wind turbine airfoil S809 and the airfoil with micro tab at 95% chord at the pressure side neat the trailing edge. The adaptive SST turbulence model was chosen to analyze the detailed flow field of the two airfoils under different angles of attack. The effect of the micro tab was brought out, and then the lift arising mechanism of the micro tab was presented. The results showed that the lift arising mechanism of the micro tab lied on the change of Kutta condition of the airfoil. The micro tab made the stagnation point move to the end of the micro tab, which made the aerodynamic profile and circulation increased. Meanwhile, the micro tab only availed at the normal working condition. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we present two novel image restoration algorithms based on a modified Hopfield neural network and variational partial differential equations (PDE). The first algorithm is based on a harmonic model and the other is based on a total variation model. Both algorithms can restore the degraded images and preserve the edges. The experimental results show that our algorithms are better than other known neural network-based restoration algorithms, especially when images mainly consist of edges, such as letters. [Copyright &y& Elsevier]

The formation of rodingites has been a continually controversial topic, largely due to the absence of minerals that can be unambiguously dated. Here, we present a case study that utilized LA‐ICPMS garnet U–Pb dating, in conjunction with field investigations, petrology and Raman spectroscopy, to reveal the age and petrogenesis of rodingite in the northern North China Craton. The rodingites are spatially associated with mafic and alkaline rocks. Our findings indicate that rodingitization occurred at ca. 388 Ma, making it about 5–10 Myr younger than its mafic protoliths, but contemporaneous with the adjoining alkaline plutons. These observations suggest that the rodingitization may be attributed to hydrothermal fluids from the alkaline magmas. Our study emphasizes the importance of utilizing garnet U–Pb dating to determine the timing of rodingitization and introduces a novel perspective on the relationship between rodingitization and alkaline magmas in extensional continental settings. [ABSTRACT FROM AUTHOR]

Ancient orogens within the supercontinent like Columbia can remain stable evolution as long as the cratons. What kind of lithospheric mantle was beneath those orogens and how it evolved into a stable state are still enigmatic. The Trans‐North China orogen (TNCO) is one of the typical collisional orogens within the Columbia supercontinent and was formed at ca. 1.85 Ga. Our work reveals that a cluster of kimberlites intruded the orogenic belt at ca. 1.54 Ga. These rocks were originally generated under a thick lithosphere (>200 km). Their entrained olivine cores show a composition of overlapping olivines from refractory mantle peridotites. The results suggest a thick and refractory lithospheric mantle beneath the TNCO at ca. 1.54 Ga. Such craton‐like property may result from large volume melt extraction from the lithospheric mantle, possibly caused by the ca. 1.78 Ga large igneous event, which eventually induces the long‐term stability of the TNCO during the subsequent supercontinent cycle. [ABSTRACT FROM AUTHOR]

The scalable reaction tolerates variously functionalized aryl carboxylic acids as well as alkyl, alkenyl, and alkynyl carboxylic acids. [ABSTRACT FROM AUTHOR]

Cu2O nanoparticles supported on carbon black are developed as an efficient catalyst for the synthesis of alkylboronic esters (III) and (V) directly from the corresponding alkyl halides. [ABSTRACT FROM AUTHOR]

The method works best for the transamidation of primary amides. [ABSTRACT FROM AUTHOR]

Rationale: In situ strontium (Sr) isotope analysis of geological samples by laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) provides useful information about magma mixing, crustal contamination and crystal residence time. Without chemical separation, during Sr isotope analysis with laser ablation, many kinds of interference ions (such as Rb+ and Kr+) are on the Sr isotope spectrum. Most previous in situ Sr isotope studies only focused on Sr-enriched minerals (e.g. plagioclase, calcite). Here we established a simple method for in situ Sr isotope analysis of basaltic glass with Rb/Sr ratio less than 0.14 by LA-MC-ICP-MS. Methods: Seven Faraday cups, on a Neptune Plus MC-ICP-MS instrument, were used to receive the signals on m/z 82, 83, 84, 85, 86, 87 and 88 simultaneously for the Sr isotope analysis of basaltic glass. The isobaric interference of 87Rb was corrected by the peak stripping method. The instrumental mass fractionation of 87Sr/86Sr was corrected to 86Sr/88Sr = 0.1194 with an exponential law. Finally, the residual analytical biases of 87Sr/86Sr were corrected with a relationship between the deviation of 87Sr/86Sr from the reference values and the measured 87Rb/86Sr. The validity of the protocol present here was demonstrated by measuring the Sr isotopes of four basaltic glasses, a plagioclase crystal and a piece of modern coral. Results: The measured 87Sr/86Sr ratios of all these samples agree within 100 ppm with the reference values. In addition, the Sr isotopes of olivine-hosted melt inclusions from the Emeishan large igneous province (LIP) were measured to show the application of our method to real geological samples. Conclusions: A simple but accurate approach for in situ Sr isotope measurement by LA-MCICP-MS has been established, which should greatly facilitate the wider application of in situ Sr isotope geochemistry, especially to volcanic rock studies. [ABSTRACT FROM AUTHOR]

To understand the oxygen fugacity (fO2) during subduction initiation, we examined proto‐arc boninites and associated mantle peridotites from the Troodos ophiolite, Cyprus. The Troodos ophiolite represents an exhumed piece of oceanic lithosphere that formed during subduction initiation in Neo‐Tethys in Late Cretaceous. Dunites and surrounding harzburgites in the Kokkinorotsos podiform chromite deposit of the ophiolite were formed by reactions between peridotites and ascending boninitic magmas. The olivine‐chromite oxybarometers show that the fO2 values (∆QFM −0.41 ± 0.37) of the dunites are slightly higher than those (∆QFM −0.85 ± 0.52) of the harzburgites under mantle conditions, indicating that the mantle fO2 was raised limitedly by percolation of the boninitic magmas. Meanwhile, the boninitic upper pillow lavas in the Margi area also recorded relatively reduced fO2 values (∆QFM −0.52 ± 0.20) during olivine‐chromite crystallization, comparable to the fO2 of mid‐ocean ridge basalts. Shallow‐level processes (i.e., magma ascent, crystallization, crustal assimilation, and degassing) appear to have limited influence on the estimated fO2 values in Troodos. The similarly low fO2 values of the mantle peridotites and boninitic magmas suggest that the Troodos primary boninitic magmas were perhaps not as oxidized as the Izu‐Bonin‐Mariana (IBM) proto‐arc boninitic magmas, though both mantle sources have captured the slab fluids released during subduction inception. This difference might be attributed to the different nature of the slab components (i.e., a more reduced subduction input for Troodos). Our study thus suggests that subducted slabs might not always release oxidized fluids, and the oxidation processes might be different for each nascent subduction zones. Plain Language Summary: Subduction zones have played a key role in mass exchange between the Earth's surface and its interior, and are one of the main factories for the generation of Earth's magmas. The redox state of arc lavas produced at subduction zones controls the formation of important mineral deposits. In fact, subduction zone lavas are believed to be generally more oxidized than mid‐ocean ridge lavas, but the origin of their oxidized nature and how their redox state change during the birth of a subduction zone remains poorly understood. Boninites are special Mg‐ and Si‐rich but Ti‐poor lavas (SiO2 > 52 wt.%, MgO > 8 wt.%, and TiO2 < 0.5 wt.%), and are typical products of magmatism that formed during subduction initiation. Here, we show that the primary boninitic magmas of the Troodos ophiolite of Cyprus are in fact no more oxidized than mid‐ocean ridge basalts, even though their mantle source interacted with the slab fluids released from the incipient subducted plate. Therefore, we propose that proto‐arc magmas, that formed as the down‐going slab began foundering, might not always be oxidized during the inception of a subduction zone. Key Points: Percolation of boninitic magmas raised the oxygen fugacity of the Troodos mantle peridotites to a limited extentThe primary boninitic magmas of the Troodos ophiolite may not be more oxidized than mid‐ocean ridge basaltsThe oxidation processes of the Troodos proto‐arc mantle may be different from those of the Izu‐Bonin‐Mariana proto‐arc mantle [ABSTRACT FROM AUTHOR]

Buffer material has been shown to be effective over the long term for radionuclide diffusion retardation and is used as the final artificial barrier of the multi-barrier system in the high-level waste disposal repository. The method of disposal raises the possibility of radionuclides escaping and returning to the biosphere when ground water enters the natural geological barrier, risking the repository's long-term stability and safety. Bentonite was chosen as the basic material in the integrated buffer material due to its low permeability, high swelling, and self-healing ability. Meanwhile, attapulgite served as an auxiliary, and pyrite served as a mineral additive. The buffer material B7AP was created by combining three materials, namely bentonite, attapulgite, and pyrite, with a mass ratio of 63:27:10. The diffusion of uranium in samples with a dry density of 1.70 g/cm3 was studied using a constant source diffusion experiment. The results showed that the B7AP buffer material had a good uranium retardation effect, with an apparent diffusion coefficient of 4.07 × 10−12 m2/s. In addition, using the theory of porous media contaminant migration, a simplified convection-dispersion-adsorption equation for uranium migration on integrated buffer material B7AP was established. MATLAB software was used to simulate time scales, seepage velocity, apparent diffusion coefficient, and retardation factor. The current study provides scientific evidence for improving retardation performance, screening, and optimizing the formula design of radioactive waste repository buffer materials. [ABSTRACT FROM AUTHOR]

An effective strategy for synthesis of Cu nanoparticles is designed, these nanoparticles have high catalytic activity in conjugate addition of B 2 (pin) 2 and α,β-unsaturated ketones. The reaction of protodeboration can proceed with adding NaO t Bu. In this way, a new method to reduce the conjugated alkenes of α,β-unsaturated ketones is developed with organoboranes as intermediates. Cu nanocrystals also have excellent performance in gram-scale reaction and recycling experiment. A possible mechanism is proposed. [ABSTRACT FROM AUTHOR]

Abstract: The rotor–stator interaction noise in axial fans is mainly caused by the periodic wake from the rotating fan impinging on the stator rows downstream. In order to accurately predict the noise, a thin-body BEM/Curle method is developed in this paper. It is a hybrid method combining computational aeroacoustic with Boundary Element Method (BEM) and can be used to predict the propagation of sound wave in the duct. The calculation includes three steps: firstly, the unsteady viscous flow around the blades is calculated using the CFD method to acquire the noise source information; secondly, the radiated sound pressure is calculated using the acoustic analogy Curle equation in the frequency domain; lastly, the scattering effect of the duct wall on the propagation of the sound wave is expressed using the thin-body BEM method. In comparison with the experimental results, the predicted sound pressure levels (SPLs) are correct in the Blade Passing Frequency (BPF) and its harmonics. The sound pressure directivities of sound source and scattering effect are shown in the paper. The conclusion is that the scattering effect of the duct wall cannot be ignored in the prediction of rotor–stator interaction noise and can increase the accuracy of the prediction in comparison with the results based on the free-field assumption. [Copyright &y& Elsevier]

Olivine‐hosted melt inclusions have the potential to provide direct evidence about the nature of the mantle sources of magmas. In this study, we report the major and trace element and Sr–Nd–Pb–Hf isotope compositions of the Lijiang picrites from the Emeishan large igneous province, as well as major and trace element and Pb isotopic compositions of olivine‐hosted melt inclusions in the picrites. Using these data, we infer the nature of the mantle sources for the Lijiang high‐Ti picrites (Ti/Y = 645–654), and compare them with the Dali low‐Ti picrites (Ti/Y = 351–408). Lijiang melt inclusions have highly heterogeneous Pb isotope compositions (208Pb/206Pb = 2.015–2.201, 207Pb/206Pb = 0.812–0.882, 260 Ma age‐corrected) that overlap the majority of the fields from FOZO to enriched mantle 1 (EM1). The primitive mantle‐normalized trace element patterns of these melt inclusions reveal an enriched composition with depletions in Ba, Nb, Ta, Zr, and Hf. We suggest that an old recycled GLOSS II‐like sediment was probably the main component that imparted the EM1 signature into the sources of the Lijiang picrites. Furthermore, we reverse calculated the mantle potential temperature (Tp) beneath Lijiang and Dali using the Al‐in‐ol temperature. The estimated mantle Tp beneath Lijiang is lower than Dali. We infer that the Lijiang picrites might have originated from the mantle plume with lower thermal energy, corresponding to the waning stage of the axis of the Emeishan mantle plume. Our study suggest that high‐Ti magmas of the Emeishan large igneous province were derived from those parts or stages of the mantle plume with lower thermal energy. Key Points: Highly heterogeneous Pb isotope compositions of olivine‐hosted melt inclusions are found in the Lijiang picritesGLOSS II‐like subduction sediments are responsible for the enriched mantle 1‐like component in the source of the Emeishan large igneous province (LIP)Thermal variation of the mantle plume controlled the types and distribution of basaltic magmas in the Emeishan LIP [ABSTRACT FROM AUTHOR]

Alkaline rocks commonly occur as volcanic-plutonic ring complexes, but the petrogenetic mechanism for the coexistence between volcanic and plutonic rocks remains controversial. The Early Cretaceous Houshihushan alkaline ring complex in the Yanshan Fold and Thrust Belt, China, contains arfvedsonite granites surrounded by syenites, trachytes and alkali rhyolites. In situ trace elements and Sr-Nd isotopic compositions of apatites from these rocks are presented to constrain the petrogenetic link between coeval alkaline volcanic and plutonic rocks. Petrographic and geochemical features suggest that apatites in the trachyte crystallized from the melt at an early stage. Their initial 87Sr/86Sr ratios (0.7048–0.7052) and ε Nd (t) values (−21.9 to −17.6) well constrain the Sr-Nd isotopic compositions of the lithospheric mantle source for the trachyte, better than those of whole-rock (0.7114 and −18.6, respectively). In contrast, apatites in the syenites crystallized from host melt throughout the whole history of magma evolution. Their geochemical features and variable initial 87Sr/86Sr ratios (0.7084–0.7175) and ε Nd (t) values (−16.0 to −12.7) suggest that the syenites were formed by the cumulation of their parental magma, coupled with gradually mixed by felsic magma with a high initial 87Sr/86Sr ratio. However, a few and small-size apatite grains crystallized from parent magma of the arfvedsonite granites and alkali rhyolites suggest that in situ geochemistry of apatites is not feasible to constrain the petrogenetic process of high-silica alkaline rocks. Combined with whole-rock data, the geochemical features and Sr-Nd isotopic compositions of apatites indicate a crystal mush model to interpret the genetic link between syenites and arfvedsonite granites and alkali rhyolites. The early accumulations of mixing mafic and felsic magmas formed syenites at the margin, while the residual silicic melts solidified as arfvedsonite granites at the core. After the exposure of the intrusive rocks by rapid exhumation, the injection of high-temperature mantle-derived magma into the crystal mush promoted the extraction of the residual melt from the magma chamber. The mantle-derived magmas and residual melts directly erupted to the surface to form trachyte and rhyolite in the middle, eventually forming the alkaline ring complex. • Distinct origins for apatite grains in the Houshihushan alkaline ring complex. • Early-stage crystallized apatite records Sr-Nd isotope signature of the source. • Apatite can reveal the detailed petrogenetic processes of alkaline rocks. • Alkaline ring complex is formed by cumulation-crystal fractionation-magma mixing. [ABSTRACT FROM AUTHOR]

High-Ti and low-Ti lava series occur simultaneously in many large igneous provinces (LIP); however, their origins remain debated. To address this issue, we performed a detailed geochemical study of olivine and olivine-hosted melt inclusions from the Dali picrites in the Emeishan LIP. Although the Dali picrite lavas have a limited range of whole-rock Ti/Y ratios (~356–404; Wu et al., 2018), olivine-hosted melt inclusions have Ti/Y ratios that range from low-Ti to high-Ti (213–741). The Sr-Pb isotopic compositions and trace element ratios (e.g., Nb/U and Nb/La) of the melt inclusions have a restricted range and display little correlation with Ti/Y ratios, indicating that the low-Ti and high-Ti lavas share compositionally similar source. Trace element mass balance modeling of the Emeishan lavas indicates a mantle source comprising ~84% peridotite from the lower mantle, ~15% recycled MORB, and ~1% pelagic sediment. Modeling results for the Emeishan and Karoo LIPs show that partial melts formed at greater depth in the mantle have higher Ti contents and Ti/Y ratios than those formed at shallower depths. Mixing between melts formed at different depths with different degrees of partial melting can produce the continuous range of Ti/Y ratios observed. The results demonstrate the strong influence of partial melting degree and pressure on the Ti content and Ti/Y ratio of partial melts. • High-Ti and low-Ti lavas in the Emeishan LIP share a common mantle source. • Melting pressure and degree have strong influence on Ti content and Ti/Y ratio. • Mixing of melts from high and low pressures accounts for high-Ti and low-Ti lavas. [ABSTRACT FROM AUTHOR]

New whole-rock major and trace elements data, zircon laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb ages, and zircon Hf isotope compositions were analysed for Early Cretaceous volcanic rocks, also called Meiriqieco Formation (MF) in the Duobuzha area of the Southern Qiangtang–Baoshan Block (SQBB), northern Tibet. Our aim is to clarify their petrogenesis and tectonic setting, and constrain the evolution process on the northern margin of Bangong–Nujiang suture zone (BNSZ) during Early Cretaceous time. The MF volcanic rocks are mainly composed of andesites with subordinate basalts and rhyolites with high-K calc-alkaline affinity. Zircon LA-ICP-MS U–Pb dating for two andesite and one rhyolite samples give uniform ages within error of ca.113, 114, and 118 Ma, respectively, indicating they were erupted on the Early Cretaceous. The MF andesites have variable zircon εHf(t) values (+0.5 to +10.5), which is different from those of MF rhyolites (+7.9 to +10.7). All the MF rocks are enriched in large ion lithophile elements, and depleted in high field strength elements, yielding the affinity of arc rocks. The MF basalts were most likely derived from the mantle wedge that was metasomatized by fluids released from subducting slab with the involvement of subducted sediments. The MF rhyolites were generated by partial melting of the juvenile mafic lower crust. The MF andesites are interpreted to have formed by mixing of the magmas that parental of the MF basalts and the MF rhyolites. In addition, a couple of distinctly magmatic sources are identified in the SQBB, and this may be related to mantle components injected into the continental crust. Combined with published geological data in the BNSZ and SQBB, we consider that the MF volcanic rocks are formed in a continental arc setting, suggesting that BNO were subducting during the Early Cretaceous time in the Duobuzha area. [ABSTRACT FROM AUTHOR]

Under the optimized conditions A), a broad spectrum of 2-aryl carboxylic acids is cyclized to benzochromenone products. [ABSTRACT FROM AUTHOR]

We present eudialyte and zircon U–Pb ages, whole-rock geochemical, and Sr–Nd–Hf and zircon Hf–O isotope data for the Xiangshuigou silicic alkaline igneous complex from the northern margin of the North China Craton (NCC). We use these data to investigate the source and petrogenesis of these alkaline igneous rocks and the lithospheric mantle evolution of the NCC. The Xiangshuigou complex consists of nepheline and porphyritic syenites without associated mafic or intermediate rocks. Zircon and eudialyte U–Pb dating yielded consistent ages of 227–219 Ma for these rocks. All the alkaline igneous rocks from the Xiangshuigou complex have high Na 2 O, Al 2 O 3 , Rb, Th, and Zr, and low MgO, CaO, P 2 O 5 , and Ba contents, and are enriched in large-ion lithophile and light rare earth elements. These rocks are not depleted in high-field-strength elements. Whole-rock Nd–Hf isotopic compositions are slightly enriched, with ε Nd (t) = −3.7 to −3.0 and ε Hf (t) = −3.1 to +0.6. Zircon Hf–O isotope analyses yielded ε Hf (t) and δ18O values of −0.6 to −6.0 and +5.1‰ to +6.0‰, respectively. These geochemical and isotopic features suggest that the silicic alkaline igneous rocks were derived by partial melting of an enriched lithospheric mantle source before experiencing protracted two-stage fractional crystallization. The lithospheric mantle source of the Xiangshuigou complex was distinct from the Paleozoic cratonic lithospheric mantle and experienced mantle metasomatism by depleted mantle-derived carbonate-bearing materials prior to the alkaline magmatism. This indicates that, in addition to subducted crustal melts/fluids, asthenosphere-derived materials were also involved in modifying the lithospheric mantle of the northern NCC. As such, our work not only approves the effectivity of using whole-rock geochemistry and Sr–Nd–Hf–O isotopic data to reveal origin of the silicic alkaline igneous rocks, but also argues for a multiple modification for the northern NCC during the late Paleozoic to early Mesozoic. • The Xiangshuigou felsic complex was formed at 227 to 219 Ma. • Felsic rocks were derived from lithospheric mantle and underwent protracted AFC. • The lithospheric mantle was modified by asthenosphere-derived materials. [ABSTRACT FROM AUTHOR]

Neurodegenerative disorders such as Huntington's disease (HD) are fundamentally caused by accumulation of misfolded aggregate-prone proteins. Previous investigations have shown that these toxic protein aggregates could be degraded through autophagy induced by small molecules as well as by nanomaterials. However, whether engineered nanomaterials have the capacity to degrade these protein aggregates via the ubiquitin-proteasome system (UPS), the other major pathway for intracellular protein turnover, was unknown. Herein, we have synthesized biocompatible MnFe 2 O 4 nanoparticles (NPs) and demonstrated their unique effect in accelerating the clearance of mutant huntingtin (Htt) protein exhibiting 74 glutamine repeats [Htt(Q74)]. UPS, rather than autophagy, was responsible for the efficient Htt(Q74) degradation facilitated by MnFe 2 O 4 NPs. Meanwhile, we demonstrated that MnFe 2 O 4 NPs enhanced K48-linked ubiquitination of GFP-Htt(Q74). Moreover, ubiqinlin-1, but not p62/SQSTM1, served as the ubiquitin receptor that mediated the enhanced degradation of Htt(Q74) by MnFe 2 O 4 NPs. Our findings may have implications for developing novel nanomedicine for the therapy of HD and other polyglutamine expansion diseases. [ABSTRACT FROM AUTHOR]