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The evolution of unified East Asian continental margin was accompanied by large-scale magmatic and tectonic events. Here we investigate the tectonic evolution history of the ocean-continent connection zone in the eastern South China Block (SCB) during the Mesozoic-Cenozoic subduction of the (Paleo-) Pacific plates based on gravity and magnetic methods that provide a window to the deep crustal structure. The decomposed multi-scale gravity wavelets reveal subduction-related intra-crustal structures and the deep structure of the Mesozoic Greater South China Block (GSCB). The depth of Moho discontinuity was inverted by gravity data, constrained by the latest global crustal model of CRUST 1.0, and the inverted depth is closely consistent with and slightly larger than the depth on seismic profiles. The undulation of the Moho discontinuity beneath the South China Block and the deep supra-crustal faults along the continental margin are considered to be associated with the subduction of the (Paleo-) Pacific plates. In general, the Moho depth in the eastern SCB gets shallower from west to east. The oblique subduction-related strike-slip faults can be traced on the 7.4 km-upward continued field of the magnetic anomaly. The geologically-indistinct Jurassic magmatic arc along the SCB continental margin is verified by residual crustal field of the Bouguer gravity anomaly. The southern Ryukyu-Taroko line is speculated as the inland segment of the Early Jurassic paleo-subduction zone, and represents the southeastern paleo-plate boundary of the GSCB in the Jurassic. As the backarc-arc-forearc paleo-system migrated eastwards since the Early Cretaceous, the subduction zone retreated to the current Taiwan-Okinawa Trough, and the Jurassic magmatic arc-forearc was transformed to a backarc, indicating an eastward migration or jumping of the Yanshanian subduction along the continental margin of the SCB. The tectonic boundary of the Mesozoic GSCB was also identified through the magnetic anomaly field and the high-order gravity field.

The NE China region involves a complex accretionary belt formed by multiple stages of assembly of micro-blocks from the Paleozoic to Mesozoic, the tectonics of which provides important clues on the evolution of the East Asian continental margin. With a view to evaluating the micro-block evolution in NE China, we used gravity and magnetic methods to analyze the geophysical characteristics of the micro-blocks and their boundaries. Combining with regional geology, paleomagnetism and paleontology, we reconstructed the micro-block assembly history in the eastern Central Asian Orogenic Belt. Five Paleozoic to Mesozoic micro-blocks are recognized in NE China: the Erguna, Xing'an, Songnen, Jiamusi and Nadanhada, and their boundaries show significant differences in gravity and magnetic fields. The boundary between the Erguna Block (EB) and the Xing'an Block (XB) shows as a continuous tectonic line in the gravity field, whereas the one between the XB and the Songnen Block (SB) exhibits a rather discrete but strong magnetic anomaly belt. The boundary between the SB and the Jiamusi Block (JB) is characterized by both distinct gravity and magnetic anomalies. The Nadanhada Micro-block (NMB) appears as an independent micro-block in the fourth-order detail field of the Bouguer gravity anomaly, where it shows as a short axis or circinate structure in this anomaly field. The Paleozoic to Mesozoic tectonic evolution of these micro-blocks in NE China is closely related to five sutures in the eastern Central Asian Orogenic Belt. The Xinlin-Xiguitu Suture was first formed at ~500 Ma, leading to the assembly of the EB and the XB, the Heihe-Hegenshan Suture was formed at 320–290 Ma, marking the amalgamation of the XB and the SB, the Mudanjiang-Yilan Suture was formed at ~200 Ma, marking the collision of the JB and the SB. The Paleo-Asian Ocean closed during 250–230 Ma in a scissor style. The subduction of the Paleo-Pacific Ocean was initiated at ~200 Ma. Based on the deep structural architecture imaged from gravity and magnetic anomalies, we propose an evolutionary model of the micro-blocks in the NE China, which provides important insights into the tectonic evolution of the NE China region during the Paleozoic to Mesozoic.

The slip behavior and mechanism of large-size Mo-3Nb single crystal have been investigated and disclosed comprehensively at room temperature by quasi-static compression with various strains. With the increase of deformation, the slip traces change from shallow non-uniform slip lines to dense and uniform slip bands. Different slip traces in the same deformation condition were observed, suggesting that the slip traces in the single crystal are controlled by different types and arrangement mechanisms of mobile dislocation. To clarify the relationship between slip behavior and dislocation arrangement, TEM and AFM analyses were performed. Significant discrepancy between the mobility of screw segments and edge segments caused by double cross-slip multiplication mechanism is the reason why different slip features were witnessed. During the whole slip deformation process, screw dislocations play a dominant role and they are inclined to form wall-substructures by interaction and entanglement. With the development of dislocation accumulation, the entangled dislocation walls evolve into dislocation cells with higher stability.

Lithium-sulfur (Li-S) batteries have drawn a lot of attention owing to the high theoretical capacity of 1675 mAh g-1, environmental friendliness and relative abundance of sulfur. Nevertheless, the severe dissolution and migration of lithium polysulfides (LiPSs) and poor conductivity of sulfur greatly hinder the practical application of Li-S batteries. In this work, Fe-Ni-P@nitrogen-doped carbon (named as Fe-Ni-P@NC) derived from Fe-Ni Prussian blue analog (Fe-Ni PBA) was used as highly efficient sulfur host for Li-S batteries. The Fe-Ni-P particles not only enhance the adsorption of LiPSs but also effectively promote the conversion of LiPSs. In addition, the CN- of PBAs can readily generate nitrogen-doped carbon during pyrolysis, which can improve the conductivity of composites. Due to these advantages, Li-S batteries using S@Fe-Ni-P@NC composites cathodes exhibited good electrochemical performance with outstanding rate capability and stable cycling over 500 cycles with a lower capacity fading rate of 0.08% per cycle at 1 C.

An efficient method for regioselective synthesis of C-7 Mannich bases of 6-hydroxyaurones was accomplished by the N,N-dialkylaminomethylation using aminals prepared from dimethylamine, dipropylamine, bis(2-methoxyethyl)amine, N-methylbutylamine, N-methylbenzylamine, morpholine, piperidine, and 1-methylpiperazine. Further transformation of 7-(N,N-dialkylamino)methyl group in these aurones led to formation of C-7 acetoxymethyl and methoxymethyl derivatives of 6-hydroxyaurones, some of which showed promising inhibition of PC-3 prostate cancer cell proliferation in the high nanomolar to low micromolar range that exceeded that of cisplatin. Compound 12c (R3 = Ac, Ar = 3,4-OMePh) displays 75% inhibition of PC-3 prostate cancer cells proliferation at 300 nM concentration.

A double-walled MOF [Zn5(μ3–OH)2(DBTA)2(H2O)4]·solvents [1, H4DBTA = 2,2′-dihydroxy-1,1′-binaphthyl-3,3′,6,6′-tetrakis(4-benzoic acid)] has been designed and constructed based on a rare Zn5 cluster. The resultant sample has enrichment of porous structure with high BET and Langmuir surface area. By virtue of multiaperture structure and plentiful catalytic sites of Bronsted (−OH) and Lewis acidic (ZnII), MOF 1 is a unique catalyst to synthesize cyclic carbonates from CO2 and epoxides with preferable repeatability.

Carbon nitride (C3N4) is promising for photocatalytic hydrogen production, but photogenerated electrons and holes in C3N4 usually tend to exist as excitons due to intrinsic Coulomb interactions making its photocatalytic activity unsatisfactory. Herein, a well-designed intramolecular C3N4-based donor-acceptor (D-A) photocatalytic system was constructed to promote exciton dissociation. Due to its good chemical compatibility with melamine and appropriate sublimation property, 2-amino-4,6-dichloropyrimidine unit was chosen as the monomer to react with melamine to construct intramolecular D-A system (CNClx). The hydrogen evolution rate of CNCl0.15 is 15.3 times higher than that of bulk C3N4 under visible light irradiation, with apparent quantum efficiency of 13.6% at 420 nm. The enhanced activity is attributed to introduced electron-withdrawing −Cl group as terminal group in the resulted CNClx samples, which can build internal electric field to promote the exciton dissociation into free electron and hole. In addition, lower work function value of CNClx samples indicates that internal electric field can help free electrons and holes transfer to the surface of CNClx samples for photocatalytic reaction.

Orphan genes are genes with no sequence homologues in other species. Here, we identified two orphan genes, namely, Tssor-3 and Tssor-4, in Plutella xylostella. Both genes contained a signal peptide sequence, suggesting their functions as secreted proteins. Expression pattern analysis based on real-time quantitative PCR (qPCR) showed that both orphan genes were specifically expressed in all male gonads except the testes. The expression of both the orphan genes peaked at the male adult stage. Immunofluorescence assays suggested that the two proteins were seminal proteins, indicating their potential roles in male reproductive regulation. To further explain their functions, we knocked down the expression of these two genes by RNA interference (RNAi). The results showed that the expression of Tssor-3 and Tssor-4 was significantly downregulated at 24 h after injection compared to that of the controls. Biological assays showed that the number of laid eggs and the hatching rate of offspring eggs were significantly reduced when the expression of Tssor-3 and Tssor-4 was reduced, suggesting that the two orphan genes played a role in male fertility in P. xylostella. Our results provide evidence that orphan genes are involved in male reproductive regulation, which is important for male fitness during evolution.

The stereoselective construction of all-carbon quaternary stereocenters, especially acyclic ones, represents an important challenge in organic synthesis. In particular, homopropargyl amides with a quaternary stereocenter β to a nitrogen atom are valuable synthetic intermediates, which could be transformed to diverse chiral structures through alkyne transformations. However, highly enantioselective synthetic methods for homopropargyl amides with a β quaternary stereocenter are extremely rare. We report here unprecedented substrate-directed, iridium-catalyzed enantioselective hydroalkynylations of trisubstituted alkenes to form an acyclic all-carbon quaternary stereocenter β to a nitrogen atom. The hydroalkynylation of enamide occurred with unconventional selectivity, favoring the more hindered reaction site. Homopropargyl amides with β-stereocenters were prepared in high regio- and enantioselectivities. Combined experimental and computational studies revealed the origin of the regio- and enantioselectivities.

Iodide-adduct chemical ionization mass spectrometry (I-CIMS) is a widely used technique in the atmospheric chemistry community to detect oxygenated volatile organic compounds (OVOCs) in real time. In this work, we report the occurrence of secondary ion chemistry from interactions between a strong oxygen donor (such as O3 and peracids) and acidic OVOCs (such as carboxylic acids and organic hydroperoxides) in the ion-molecule reaction (IMR) region of I-CIMS. Such interactions can lead to acidic organic molecules (HA or HB) clustering with [IO]- (e.g., [HA + IO]-) and dimer adducts ([A + B + I]-), in addition to the well-known iodide clusters ([HA + I]-). This ion chemistry was probed using common chemical standards as well as the gas-phase oxidation products of α-pinene and isoprene in a flowtube reactor. The results show that secondary ion chemistry can lead to misinterpretations of molecular compositions and distributions of the gas-phase products and an overestimation of the elemental O/C ratio overall. Nevertheless, the varying degrees of signal change in response to the secondary ion chemistry might be a clue to inform OVOCs' functionalities. Specifically, in the α-pinene ozonolysis system, the extents of ion signal reduction in the presence of additional acids in the IMR suggest that C9H14O4 produced in the gas phase is a peracid, rather than the often-assumed pinic acid. Thus, we suggest that the potential application of the secondary ion chemistry to inform organic functionalities is promising, which could help better understand the molecular compositions of gas-phase OVOCs and the reaction mechanisms therein.

Cardiovascular disease (CVD) results in more than half of the mortality and the majority of morbidity in patients with type 2 diabetes. We aim to evaluate the associations of urinary concentrations of phthalate metabolites with CVD in diabetic patients and explore whether CVD risk factors mediate or interact with these associations. A total of 675 type 2 diabetic participants were enrolled from Shanghai, China, in 2018. CVD was defined as a self-reported diagnosis by a physician including coronary heart disease, myocardial infarction, or stroke; it was further reconfirmed in the records from the registration platform. Ten phthalate metabolites were measured in urine. We found positive associations were found among the level of monoethyl phthalate and monoisobutyl phthalate and CVD (OR 1.138, 95% CI 1.032, 1.254; OR 1.369, 95% CI 1.049, 1.786, respectively). Monoisobutyl phthalate and monobenzyl phthalate were marginally and positively associated with carotid intima-media thickness and common carotid artery diameter, respectively. None of the CVD risk factors, including HOMA-IR, body mass index, lipid profile, or blood pressure, significantly mediated the association between the metabolites and CVD. The conditional indirect effect on CVD was significantly stronger for current smoking and dyslipidemia for monoethyl phthalate and for no statin usage and men for monoisobutyl phthalate. In conclusion, phthalate exposure was positively associated with CVD in Chinese with type 2 diabetes. Type 2 diabetic men who are currently smoking, have an uncontrolled lipid profile, and are not using statins might be more susceptible to CVD when exposed to phthalates.

Five new cassane-type diterpenoids, including 16-O-ethyl caesalpin A (1), 16-O-ethyl caesalpin B (2), norcaesalpinin ME (3), 6α-hydroxynorcaesalpinin A (4), and 17-acetylcaesalmin Z (5), were isolated from the seeds of Caesalpinia minax Hance, along with twelve known compounds. The structures of the new compounds were established by means of spectroscopic technique (NMR, HRESIMS and IR). The absolute configurations of the new compounds were determined by their ECD spectra. In palmitic acid/oleic acid-treated AML12 mouse hepatocytes, compound 5 greatly reduced intracellular lipid accumulation, as well as total triglyceride and cholesterol contents, which could be further developed to treat fatty liver disease.

In our previous studies, a kind of novel benzenesulfonamides was found to be a candidate insecticidal compounds. It was shown that propargyloxy and sulfonamide groups are pharmacodynamic groups. One hundred and twenty-six (126) naphthalenesulfonamides derivatives with propargyloxy functionality were designed and synthesized, and their insecticidal activities were determined. Some of them showed outstanding activity, with LC50 values as low as 0.202 mg ml-1, much lower than that of the positive control celangulin V (23.9 mg ml-1). In addition, the structure-activity relationships were discussed, and molecular docking was used to verify the binding mode of the compound and the target receptor.

The development of a cost-effective photocatalyst is highly anticipated to achieve efficient photocatalytic CO2 reduction with superior selectivity, which is still facing the lack of valid settlements. Herein, 4-mercaptopyridine (PD) as the building block of a capping ligand is tightly decorated on the surface of CdS nanocrystals (CdS-PD) using a facile ligand-exchange strategy, to exploit a cost-effective photocatalyst for photocatalytic CO2 reduction without any cocatalysts. The conjugated structure of PD can facilitate the delocalization of photogenerated electrons in CdS nanocrystals, bringing forth an improved charge separation efficiency. More importantly, N-protonated PD can enable the easy formation of a six-membered ring intermediate with CO2 assisted by water, which can serve as the efficient active site to achieve photocatalytic CO2 reduction. In the absence of a cocatalyst, stand-alone CdS-PD nanocrystals exhibit an excellent CO yield of 20.35 mmol g-1 h-1 concomitant with a high selectivity of 95.3% for the CO2-to-CO conversion under visible light, which are remarkably superior than those of CdS nanocrystals possessing traditional alkyl-chain and other conjugated capping ligands.

The microstructure, precipitates and properties of 25CrNiMoV (DZ2) steel for high-speed railway axles with different Nb contents were investigated by means of optical microscopy, scanning electron microscopy, electron back-scattering diffraction, transmission electron microscopy and physicochemical phase analysis. The results show that the grain size of the original austenite of the test steels decreases from 20.5 to 14.2 and 10.8 μm after adding 0.026 and 0.039 wt.% Nb to a 25CrNiMoV steel, respectively. Moreover, the block width of the tempered martensite in the test steels is refined from 1.91 to 1.72 and 1.60 µm, respectively. MC-type precipitates in 25CrNiMoV steel are mainly VC, while (Nb,V)C gradually precipitates when Nb is microalloyed, and the amount of precipitates increases with increasing Nb content. Through strengthening mechanism analysis, it is found that grain refinement strengthening is the primary way to increase the strength. The improvement in the yield strength with increasing Nb content is attributed to a significant increase in precipitation strengthening, grain refinement strengthening and dislocation strengthening.

Current-induced magnetization switching by spin-orbit torque generated in heavy metals offers an enticing realm for energy-efficient memory and logic devices. The spin Hall efficiency is a key parameter in describing the generation of spin current. Recent findings have reported enhancement of spin Hall efficiency by mechanical strain, but its origin remains elusive. Here, we demonstrate a 45% increase in spin Hall efficiency in the platinum/cobalt (Pt/Co) bilayer, of which 78% of the enhancement was preserved even after the strain was removed. Spin transparency and X-ray magnetic circular dichroism revealed that the enhancement was attributed to a bulk effect in the Pt layer. This was further confirmed by the linear relationship between the spin Hall efficiency and resistivity, which indicates an increase in skew-scattering. These findings shed light on the origin of enhancement and are promising in shaping future utilization of mechanical strain for energy-efficient devices. Agency for Science, Technology and Research (A*STAR) Economic Development Board (EDB) National Research Foundation (NRF) Submitted/Accepted version This work is supported by an Industry-IHL Partnership Program (NRF2015-IIP001-001) and an EDB-IPP (RCA − 17/284) grant. This work is also supported by the RIE2020 ASTAR AME IAF-ICP grant (No. I1801E0030). W.Z. and P.K.J.W. acknowledge financial support by the Fundamental Research Funds for the Central Universities.

Four new 9,10-secosteroids, verrucellols A-D (1-4), together with 12 known derivatives (5-16) were isolated from the gorgonian Verrucella umbraculum collected in the South China Sea. The structures of the new compounds were established by spectroscopic analysis and comparison with reported data. These compounds exhibited significant suppressive effects on CD4+ T lymphocyte cell differentiation in an in vitro bioassay. This is the first report of 9,10-secosteroids exhibiting immunomodulation activity.

Up to now, the majority of the developed photocatalytic CO2 reduction systems need to use expensive sacrificial reductants as electron source. It is still a huge challenge to drive the photocatalytic CO2 reduction using water as an electron source. Herein, we report a facile strategy for the construction of direct Z-scheme heterojunction of LF-FAPbBr3/α-Fe2O3, which is manufactured by the in situ and two-step controlled growth of ligand-free formamidinium lead bromide (LF-FAPbBr3) nanocrystals on the surface of α-Fe2O3 nanorods. The matchable energy levels and direct contact between LF-FAPbBr3 and α-Fe2O3 significantly accelerate the interfacial charge transfer, with a charge separation efficiency (ηseparation) of 93%, much higher than that of 11% shown by the ligand-capped FAPbBr3/α-Fe2O3 heterojunction. The resulting efficient separation and raised redox ability of photogenerated carriers endow the LF-FAPbBr3/α-Fe2O3 heterojunction with an outstanding photocatalytic performance for CO2 reduction (to CO and CH4) coupled with water oxidation (to O2), achieving a highest electron consumption rate of 175.0 μmol g-1 h-1 among the reported metal halide perovskite-based photocatalysts, which are 5 and 11 times higher in comparison with those of sole LF-FAPbBr3 and ligand-capped FAPbBr3/α-Fe2O3, respectively.

In recent years, PD-1 immune checkpoint inhibitors based on monoclonal antibodies have revolutionized cancer therapy, but there still exist unresolved issues, such as the high cost, the relatively low response rates, and so on, compared with small-molecule drugs. Herein a type of pyrrole-imidazole (Py-Im) polyamide as a small-molecule DNA binder was designed and synthesized, which could competitively bind to the same double-stranded DNA stretch in the PD-L1 promoter region as the STAT3 binding site and thus downregulate PD-L1 expression. It was demonstrated that the Py-Im polyamides directly caused apoptosis in tumor cells and retarded cell migration in the absence of T cells through inhibiting the Akt/caspase-3 pathway. Also, in a coculture system, they enhanced the T-cell-mediated killing of tumor cells by the reversal of immune escape. Because such polyamides induced antitumor effects via both immune and nonimmune pathways, they could be further developed as promising PD-L1 gene-targeting antitumor drugs.

A multicomponent (TiZrHfNbTaMo)C ceramic has been fabricated by pressureless sintering at temperatures from 2100 °C to 2500 °C, using an equimolar multicomponent carbide powder synthesized by carbothermal reduction as the starting material. Influence of sintering temperature on densification, microstructure and mechanical properties of the ceramics was investigated. The relative density increases with increasing sintering temperature, and a nearly fully dense sample is achieved by pressureless sintering at 2500 °C. Average grain size increases from 3.7 to 15.2 μm with increasing sintering temperature from 2300 to 2500 °C. The (TiZrHfNbTaMo)C ceramic sintered at 2400 °C exhibits a single phase fcc structure with homogeneous chemical composition, an average grain size of 7.0 μm and a relative density of 96.5%, while its measured hardness is 33.2 GPa at 100 mN and 23.2 GPa at 9.8 N.

The demand for sustainable energy has motivated the development of artificial photosynthesis. Yet the catalyst and reaction interface designs for directly fixing permanent gases into liquid fuels are still challenged by sluggish mass transfer and catalytic kinetics at the gas-liquid-solid three-phase boundary. Here, we report that breathable metal-organic framework (MOF) membranes decorated with metal single-atoms (SAs) can synergistically promote the diffusion, adsorption, and activation of gas molecules (e.g. CO2, O2) to boost the photocatalytic conversion of them into liquid fuels. With Ir SAs as active centers, the defect-engineered MOF (e.g. NH2-UiO-66) matrixes can efficiently harvest visible light and sensitize the electronically tailored Ir SAs for reducing CO2 to HCOOH with the high activity of 0.51 mmol gcat-1 h-1 at the conventional three-phase reaction interface. Furthermore, the breathable SA/MOF membranes can directly convert humid CO2 gas into HCOOH at the high-throughput gas-solid interfaces, presenting a near-unity selectivity and an unprecedented activity of 3.38 mmol gcat-1 h-1. Similarly, with Pd SAs as active centers, the SA/MOF membrane can catalyze the O2-to-H2O2 conversion with an ultrahigh activity of 10.4 mmol gcat-1 h-1 under visible light, suggesting the wide applicability of our catalyst and reaction interface designs.

To increase the conductivity of proton exchange membranes in the membrane thickness direction, a novel mixed matrix membrane of Nafion ionomer and sulfonated graphene nanoplates (sGNP) with aligned proton channels is prepared with the assistance of an electric field. A high voltage alternative electric field is applied to a casting solution consisting of Nafion ionomer, sGNP, N, N-dimethylformamide (DMF), and p-xylene (PX) while evaporating the solvents. The sGNP, naturally attracting the ionic groups of Nafion ionomer to their vicinity, is polarized and rotated under the electric field, leaving aligned proton channels in the solidified membrane. The trans-plane proton conductivity of the mixed matrix membrane can reach 0.155 S cm−1 at 80 °C and 100% RH, an increase of 48% as compared with the conventional cast Nafion membrane. Accordingly, the peak power output of H2/O2 fuel cell with the mixed matrix membrane increases by 15%, reaching 440 mW cm−2 at 80 °C.

To study the pollution features and underlying mechanism of PM2.5 in Luoyang, a typical developing urban site in the central plain of China, 303 PM2.5 samples were collected from April 16 to December 29, 2015 to analyze the elements, water soluble inorganic ions, organic carbon and elemental carbon. The annual mean concentration of PM2.5 was 142.3 μg/m3, and 75% of the daily PM2.5 concentrations exceeded the 75 μg/m3. The secondary inorganic ions, organic matter and mineral dust were the most abundant species, accounting for 39.6%, 19.2% and 9.3% of the total mass concentration, respectively. But the major chemical components showed clear seasonal dependence. SO42− was most abundant specie in spring and summer, which related to intensive photochemical reaction under high O3 concentration. In contrast, the secondary organic carbon and ammonium while primary organic carbon and ammonium significantly contributed to haze formation in autumn and winter, respectively. This indicated that the collaboration effect of secondary inorganic aerosols and carbonaceous matters result in heavy haze in autumn and winter. Six main sources were identified by positive matrix factorization model: industrial emission, combustion sources, traffic emission, mineral dust, oil combustion and secondary sulfate, with the annual contribution of 24%, 20%, 24%, 4%, 5% and 23%, respectively. The potential source contribution function analysis pointed that the contribution of the local and short-range regional transportation had significant impact. This result highlighted that local primary carbonaceous and precursor of secondary carbonaceous mitigation would be key to reduce PM2.5 and O3 during heavy haze episodes in winter and autumn.

Poly (N-ethylaniline) (PNEA) composites with varying silicate content were fabricated on copper through a novel electropolymerized strategy in acidic solution. Thickness, compactness, conductivity and adhesive strength of the composite (PNEA-10Si) were optimized as silicate content reached 10 mM. Electrochemical, morphological and solution analyses were employed to evaluate the protective performance of PNEA and PNEA-10Si coatings for copper in 3.5 % NaCl solution. Results of electrochemical analyses indicated that as-prepared coatings retarded the oxygen reduction process efficiently for copper in 3.5 % NaCl solution, drained corrosion current density and elevated interfacial charge transfer resistance. Due to favorable barrier effect, compact structure and low porosity index, PNEA-10Si composite exhibited superior anti-corrosive performance, which was more tolerant than PNEA during long-time immersion. PNEA-10Si coated sample exhibited a stable topography after 144 h immersion with the minimum concentration of released ions revealing the improved protection capacity. Electronic/atomic-multiscale calculations were conducted to clarify the deposition and protection mechanism of as-prepared coatings. Outcomes of density functional theory corroborated that silicate is stabilized in the PNEA layer via electrostatic force; and immobile silicate positively contributed to the charge transfer barrier of the composite. Molecular dynamics simulations evidenced that the favorable compatibility between PNEA and silicate facilitated polymer deposition and confined in-situ ions diffusion.

Liver cancer is one of the most frequent causes of cancer-related deaths worldwide. The current study sought to screen, for the first time, a Ficus carica variety from the Shandong province of China against hepatocellular (HepG2) cells. Crude extracts of F. carica with various polarities were prepared and screened against HepG2 cells. The acetone extract of the leaf (FLA) exhibited significant antiproliferative effects against HepG2 cells (IC50 = 0.179 mg/mL) while producing the least toxicity on normal human umbilical vein endothelial cells (HUVECs). Biochemical evidence of apoptosis was confirmed by staining with DAPI and AO/EB. FLA also exhibited moderate anti-colonization potential against the population of HepG2 cells. It selectively arrested the cell cycle of HepG2 cells at the S phase and exerted anticancer activity by significantly increasing the reactive oxygen species (1.59 fold) inside the cells, which subsequently resulted in loss of the mitochondrial membrane potential as revealed by JC-1 probe assay. FLA downregulated the expression of tumor-promoter Transcription Factor (TP53), anti-apoptotic proteins (Bcl-2), and cell cycle regulatory kinases (CDK1, 5, 9) with respect to untreated cells for 24 h, 48 h, and 72 h. High-performance liquid chromatography (HPLC) of FLA revealed the presence of gallic acid and quercetin as major antiproliferative compounds along with trace amounts of rutin, luteolin, apigenin, benzoic acid, and β-sitosterol. Notably, our study showed FLA operating via novel mechanisms involving reactive oxygen species (ROS) generation and CDKs involvement in HepG2 cells. Thus, it suggests that FLA may be a potential source of new drugs in the treatment of liver cancer.

Magnetism in monolayer (ML) VSe2 has attracted broad interest in spintronics, while existing reports have not reached consensus. Using element-specific X-ray magnetic circular dichroism, a magnetic transition in ML VSe2 has been demonstrated at the contamination-free interface between Co and VSe2. Through interfacial hybridization with a Co atomic overlayer, a magnetic moment of about 0.4 NB per V atom in ML VSe2 is revealed, approaching values predicted by previous theoretical calculations. Promotion of the ferromagnetism in ML VSe2 is accompanied by its antiferromagnetic coupling to Co and a reduction in the spin moment of Co. In comparison to the absence of this interface-induced ferromagnetism at the Fe/ML MoSe2 interface, these findings at the Co/ML VSe2 interface provide clear proof that the ML VSe2, initially with magnetic disorder, is on the verge of magnetic transition.

Lead (Pb) exposure has been reported to have nephrotoxicity. However, such an effect has not been well investigated in type 2 diabetes (T2D) patients, especially when taking into account the nutrition status of the patients. Therefore, we explore the association between blood lead levels (BLLs), dietary intake of nutrients, and impaired renal function among patients with T2D. We measured BLLs and biochemical parameters of renal injury in 780 patients. Dietary nutrients intake was assessed by a food frequency questionnaire in 420 of 780 participants. We found high BLLs were significantly associated with certain parameters of renal injury, and dietary intake of specific nutrients (mainly micronutrients) was associated with reduced BLLs at high percentile distribution of concentration. BLLs were also found to have moderation effects on the association between specific dietary nutrients and specific renal function parameters.

A couple of enantiomers of 2, 6-diaminotriptycene ( R, R - 1 and S, S - 1 ) are split by chiral HPLC and their absolute configurations are identified by single-crystal X-ray diffraction technology. Using the enantiomers as monomers, a couple of chiral porous polyimides ( R - FTPI and S - FTPI ) are prepared by polycondensation reactions and display good heat stability, high BET surface area and good solubility in organic solvents. Moreover, both of R - FTPI and S - FTPI can be cast into robust, free-standing films suitable for enantioselective separation with symmetrical chiral selectivity.

Construction of eight-membered silacycles via Pd-catalyzed (4 + 4) annulation of silacyclobutanes and 2-iodobiphenyl derivatives is described. This strategy involves direct C–H and C–Si bond activa...

Reducing the size of heterogeneous nanocatalysts is generally conducive to improving their atomic utilization and activities in various catalytic reactions. However, this strategy has proven less effective for Cu-based electrocatalysts for the reduction of CO2 to multicarbon (C2+) products, owing to the overly strong binding of intermediates on small-sized (< 15 nm) Cu nanoparticles (NPs). Herein, by incorporating pyrenyl-graphdiyne (Pyr-GDY), we successfully endowed ultrafine (∼ 2 nm) Cu NPs with a significantly elevated selectivity for CO2-to-C2+ conversion. The Pyr-GDY can not only help to relax the overly strong binding between adsorbed H* and CO* intermediates on Cu NPs by tailoring the d-band center of the catalyst, but also stabilize the ultrafine Cu NPs through the high affinity between alkyne moieties and Cu NPs. The resulting Pyr-GDY-Cu composite catalyst gave a Faradic efficiency (FE) for C2+ products up to 74%, significantly higher than those of support-free Cu NPs (C2+ FE, ~ 2%), carbon nanotube-supported Cu NPs (CNT-Cu, C2+ FE, ~ 18%), graphene oxide-supported Cu NPs (GO-Cu, C2+ FE, ~ 8%), and other reported ultrafine Cu NPs. Our results demonstrate the critical influence of graphdiyne on the selectivity of Cu-catalyzed CO2 electroreduction, and showcase the prospect for ultrafine Cu NPs catalysts to convert CO2 into value-added C2+ products.

The Chinese South Tianshan (CSTS) on the southwestern margin of the Central Asian Orogenic Belt (CAOB) is a vital tectonic location to elucidate the links between the prevailing Cimmerian collisional orogenic process and uplift mechanisms in the whole CAOB. To constrain the CSTS exhumation processes, we determined systematic zircon U–Pb, biotite and K-feldspar 40Ar/39Ar and apatite (U-Th)/He ages of plutons from Hark and Erbin Mountains in the CSTS and the Bachu Uplift in the Tarim Basin (for comparative study). The results reveal spatial and temporal disparities in the CSTS thermal history and exhumation processes, which can be classified into three stages. Stage I (P1): intrusive bodies experienced magmatic cooling episodes after emplacement, revealing a deeper emplacement location for the pluton in Hark Mountain than in Erbin Mountain and the Bachu Uplift. Stage II (P2-K): Hark Mountain experienced rapid cooling and exhumation processes (3.0 °C/Ma, 0.14 mm/year) compared with the Erbin Mountain (2.0 °C/Ma, 0.09 mm/year) and Bachu Uplift (1.8 °C/Ma, 0.07 mm/year), resulted from the Qiangtang-Kunlun collision and Qiangtang-Lhasa collision in the south. Stage III (Cz): Rapid Cenozoic exhumation in the CSTS weakened eastward; the latest and most rapid uplift occurred in Hark Mountain to the west (8.6 Ma, 5.5 °C/Ma), after the eastern Ouxidaban pluton (31.1 Ma) and Erbin Mountain (56.4 Ma, 0.8 °C/Ma), possibly related to the remote effects of the India-Eurasia collision. Further, the northern Bachu Uplift could have been rigid enough that could transmit the driving forces in southern Eurasia from south to north during the Cenozoic.

This paper studies the double-parameter multi-pulse jumping chaotic vibrations and metastable chaos of the bistable asymmetric composite laminated square panel under combined external and parametric excitations for the first time. The double-parameter multi-pulse jumping chaotic motions are studied by using the extended Melnikov method for the bistable asymmetric composite laminated square panel. It is indicated that there exist the Shilnikov type multi-pulse jumping orbits. The occurred mechanism of the metastable chaos is first analyzed. A theoretical explanation is given for coexisting in the double-parameter multi-pulse jumping chaotic vibrations and metastable chaotic behaviors. Using the double-parameter Lyapunov exponents, the double-parameter nonlinear dynamics of the bistable asymmetric composite laminated square panel are analyzed. According to the numerical simulation results, the in-depth investigation of the topological changes is obtained for the double-parameter multi-pulse jumping chaotic vibrations. It is found that the dynamic snap-through phenomena and the coupled effects of the external and parametric excitations on the double-parameter nonlinear dynamic behaviors are obtained for the bistable asymmetric composite laminated square panel. It is also observed that the change of the external excitation can only affect the complexity of the chaotic vibrations. However, the parametric excitations determine the types of the chaotic vibrations. There exists a direct connection between the occurrence of the metastable state chaos and the increase of parametric excitations for the bistable asymmetric composite laminated square panel.

Drug-induced liver injury (DILI) is the most common reason for the post-marketing withdrawal of drugs. Poor understanding of the mechanisms of DILI presents a large challenge in clinical diagnosis. Previous evidences indicate a potential relationship between reactive nitrogen species (RNS) and DILI. Hence, we developed two specific probes, Golgi-HNO and Mito-HNO, for the multicolored and simultaneous in situ imaging of nitroxyl (HNO) in the Golgi apparatus and mitochondria, respectively. We discovered a significant rise in HNO levels in the livers of mice with DILI, which means that for the first time, we revealed a positive correlation between HNO levels and DILI. Based on changes in the HNO level, we also successfully explored the extent of liver damage induced by an anticarcinogen, bleomycin. In addition, we uncovered catalase was involved in HNO synthesis, which is the unprecedented function of catalase. These findings demonstrate that HNO is an ideal biomarker for DILI diagnosis, and Golgi-HNO and Mito-HNO are ideal fluorescent probes to study in situ HNO changes in various physiological and biochemical processes.

Photocatalytic nitrogen fixation reaction can harvest the solar energy to convert the abundant but inert N2 into NH3. Here, utilizing metal-organic framework (MOF) membranes as the ideal assembly of nanoreactors to disperse and confine gold nanoparticles (AuNPs), we realize the direct plasmonic photocatalytic nitrogen fixation under ambient conditions. Upon visible irradiation, the hot electrons generated on the AuNPs can be directly injected into the N2 molecules adsorbed on Au surfaces. Such N2 molecules can be additionally activated by the strong but evanescently localized surface plasmon resonance field, resulting in a supralinear intensity dependence of the ammonia evolution rate with much higher apparent quantum efficiency and lower apparent activation energy under stronger irradiation. Moreover, the gas-permeable Au@MOF membranes, consisting of numerous interconnected nanoreactors, can ensure the dispersity and stability of AuNPs, further facilitate the mass transfer of N2 molecules and (hydrated) protons, and boost the plasmonic photocatalytic reactions at the designed gas-membrane-solution interface. As a result, an ammonia evolution rate of 18.9 mmol gAu-1 h-1 was achieved under visible light (>400 nm, 100 mW cm-2) with an apparent quantum efficiency of 1.54% at 520 nm.

Here, we describe a new photoelectrochemical imaging method termed light-addressable square wave voltammetry (LASWV). It measures local SWV currents at an unstructured electrolyte/insulator/semiconductor (EIS) field-effect substrate by illuminating and addressing the substrate with an intensity-constant laser. Due to the continuous generation of charge carriers in the light-irradiated semiconductor, the drift and diffusion of photoinjected carriers within the semiconductor bulk would slow down the equilibrium processes of charge and discharge in one potential pulse cycle. Therefore, even though SWV is sampled at the end of the direct and reverse pulses to reject capacitive currents, in our approach, photoinduced capacitive current can still be detected as an effective sensory signal. The obtained current-potential (I-V) curve shows a typical shape corresponding to the accumulation, depletion, and inversion regions of field-effect devices. We demonstrated that LASWV can be used as a field-effect chemical sensor to measure the solution pH and monitor enzymatic reactions. More importantly, since the charge carriers are only generated in the illuminated area, the laser spot in the device can be used as a virtual probe to record local electrochemical properties such as impedance with microresolution.

Background Bone is thought to be the reservoir of the human lead burden, and vitamin D is associated with bone turnover. We aimed to explore whether exposure to lower 25-hydroxy vitamin D (25(OH)D) levels was associated with higher blood lead levels (BLLs) by increasing the bone turnover rate in individuals with type 2 diabetes. Methods A total of 4103 type 2 diabetic men and postmenopausal women in Shanghai, China, were enrolled in 2018. Their 25(OH)D, β-C-terminal telopeptide (β-CTX), N-MID osteocalcin and procollagen type 1 N-peptide (P1NP) levels were detected. Their BLLs were determined by atomic absorption spectrometry. Mediation analyses were performed to identify the possible role that bone turnover played in the underlying mechanisms. Results In both the men and postmenopausal women, all three bone turnover markers were inversely associated with 25(OH)D and positively associated with the BLL (all P < 0.01) after adjusting for age, current smoking habits, metabolic parameters, duration of diabetes, vitamin D intake, and use of anti-osteoporosis medication. In the mediation analyses, none of the direct associations between 25(OH)D and BLL was significant for the three bone turnover markers, but all three bone turnover markers were found to be significant mediators of the indirect associations between 25(OH)D and BLL. Conclusion The association between vitamin D and BLL was fully mediated by bone turnover markers in type 2 diabetic patients (mediation effect). This finding suggested that vitamin D may protect against blood lead exposure from the bone reservoir by decreasing bone turnover in individuals with type 2 diabetes.

The excessive production and deposition of amyloid-β (Aβ) is one of the most important etiologies of Alzheimer's disease (AD). The interaction between Aβ and metal ions produces aberrant reactive oxygen species (ROS), which induce oxidative stress and accelerate the progression of AD. To reduce Aβ plaques and ROS to maintain their homeostasis is an emerging and ingenious strategy for effective treatment of AD. Herein, we report the rational design of multifunctional micelles (MPGLT) based on a polymer-grafted peptide to simultaneously clear Aβ and ROS for AD therapy. The MPGLT integrating three functional peptides as a ROS scavenger (tk-GSH), β-sheet breaker (LP) and an autophagy activator (TK) respectively, could capture and degrade Aβ. Meanwhile, the tk-GSH on the surface of MPGLT effectively scavenges the intracellular ROS. Consequently, MPGLT reduced the cytotoxicity of Aβ and ROS. In vivo animal studies using an AD mouse model further showed that MPGLT could transport across the blood–brain barrier for decreasing the Aβ plaque and eliminating ROS in vivo. This peptide micelle-based synergistic strategy may provide novel insight for AD therapy., Multifunctional micelles based on a peptide–polymer for simultaneously targeting Aβ degradation and ROS scavenging for AD therapy.

To search naturally occurring interleukin-1β (IL-1β) inhibitors, biscaesalmins A (1) and B (2), two highly oxidized dimeric cassane diterpenoids with a newly formed alicyclic skeleton, have been isolated from the traditional Chinese medicine Kushilian (Caesalpinia minax). Their full structures were determined by comprehensive spectroscopic analysis and quantum chemical TD-DFT (time-dependent density functional theory) calculation. Biosynthetically, 1 and 2 were formed via an intermolecular [4 + 2] Diels-Alder cycloaddition of two monomers, affording an additional six-membered carbon ring linkage. Compounds 1 and 2 inhibited nitric oxide production on lipopolysaccharide-stimulated THP-1 macrophages, with IC50 values being at 1.20 ± 0.23 and 2.30 ± 0.15 μmol/L, respectively. Furthermore, compound 1 inhibited NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) inflammasome-mediated IL-1β production and blocked the migration of macrophages towards adipocyte conditioned medium. Biscaesalmins A and B might be candidates for treating inflammation-related metabolic diseases.

Precipitation is particularly scarce in arid Central Asia (CA), and is expected to be severely impacted by future warming, and the assessment of the stationarity of precipitation variability is important for managing surface water resources in this region. In this study, we investigated the statistics of stationarity in the totals and extremes of precipitation in CA based on the longest observational records (1881–2006), tree-ring reconstructed records (1756–2012 and 1760–2015), and the Coupled Model Intercomparison Project 5 (CMIP5) simulations, applying the autocorrelation function and testing criteria established based on the statistical definitions of stationarity. We analyzed the longest daily precipitation record (Tashkent station, 1881–2006) and found that the autocorrelation coefficient of the precipitation totals (PRCPTOT) and annual maximum 1-day precipitation amount (Rx1day) were statistically insignificant for all lags, implying stationary behavior. Regionally, nearly all the Global Historical Climatology Network-Daily Database (GHCN-D) observatory sites (1925–2005) indicated likely stationary behavior. The reconstructed records were also indistinguishable from a random process. For the CMIP5 models, the simulated and projected PRCPTOT closely approximated a purely random process; however, the projected Rx1day maintained non-stationary means in most of the models under the representative concentration pathway (RCPs), implying that extreme events would increase in the future. The mean precipitation changes (ΔP) can be expressed as an exponential function depending on the length of the successive mean periods ( μ ) and variance ( σ 2 ). The ΔP of the next decade is projected to be within ±14.8% of the previous decades mean annual PRCPTOT over CA. The higher the RCPs, the higher the ΔP over CA. The results show that the detection and prediction of precipitation change will be challenging in arid CA.

Aiming at fabricating high-activity and stable methane combustion catalysts in the dry/wet conditions, Co–Mn binary oxides were employed as promoters to Pd/Al2O3 system herein. The introduction of appropriate amount of manganese made Mn3+ maximally enter into the Co3O4 spinel structure, conducive to the conversion of Co3+ to Co2+ by Mn3+ and then the enhancement of lattice distortion. Therefore, abundant oxygen vacancies were produced, which enhanced the surface-concentrations of active Pd2+ and Oads species, together with the exchange of oxygen species. The resulting catalyst with a molar Mn/Co ratio of 0.20 performed superior low-temperature activity and durability. Moreover, the synergy of Mn and Co could accelerate the removal process of accumulated OH/H2O from the active sites, thereby promoting the regeneration of PdO and oxygen vacancies. This endowed the tailored catalyst with remarkable moisture-tolerance and hydrothermal stability, and inspiring enhanced activity (T90 = 350 °C) after removing water vapor.

Summary The role of adsorbent flexibility for adsorptive separation is controversial. Here, we show that the gating action, an unconventional type of flexibility, can be used to achieve molecular sieving. Two isostructural metal-organic frameworks possessing quasi-discrete/gating pores are designed and synthesized, which allow CO2 adsorption from extremely low pressures. Adding amino group on the organic ligand strengthens intra-framework hydrogen bonding, which increases the gating energy barrier to completely block N2 and CH4 with larger sizes, giving record-high CO2/N2 and CO2/CH4 selectivities. C2 and C3 hydrocarbons larger than the pore induce pore opening at significantly different pressures implying C2H4/C2H6 and C3H6/C3H8 molecular sieving. Quantitative mixture breakthrough experiments show CO2/N2 and CO2/CH4 molecular sieving and the first example of switchable C2H4/C2H6 adsorption preference, but reveal C3H6/C3H8 co-adsorption. Computational simulation and in situ single-crystal/powder X-ray diffraction show that the absence and presence of pore opening are responsible for molecular sieving and co-adsorption, respectively.

With the increasingly serious problem of surface water environmental safety, it is of great significance to study the changing trend of reservoir water quality, and it is necessary to establish a water quality prediction and early warning system for the management and maintenance of water resources. Aiming at the problem of water quality prediction in reservoirs, a CA-NARX algorithm is designed, which combines the improved dynamic clustering algorithm with the idea of machine learning and the forward dynamic regression neural network. The improved dynamic clustering algorithm is used to classify the eutrophication degree of waterbodies according to the total phosphorus and total nitrogen content. Considering four meteorological factors, air temperature, water temperature, water surface evaporation, and rainfall, synthetically for each water quality condition, the total phosphorus and total nitrogen in the waterbody are forecasted by an improved forward NARX dynamic regression neural network. Based on this, the CA-NARX prediction algorithm can realize short period water quality prediction. Compared with the traditional support vector regression machine model, improved GA-BP neural network, and exponential smoothing method, the CA-NARX model has the least prediction error.

There is no shortcut to a carbon neutral society; solutions are urgently required from both energy & industrial sectors and global ecosystems. While the former is often held accountable and emphasized in terms of its emissions reduction capability, the latter (recently termed natural climate solutions) should also be assessed for potential and limitations by the scientific community, the public, and policy makers.

A one-step protocol of the aryl iodine-catalyzed aminolactonization of unactivated alkenes under oxidation conditions was first reported to efficiently construct diverse amino lactones in a short time using HNTs2 as the compatible nitrogen source. In addition, we investigated the influence of the reaction rate based on the structure of the iodoarene precatalyst, which revealed the selective adjustment effect on aminolactonization and oxylactonization. Finally, preliminary experiments verified the feasibility of asymmetric aminolactonization catalyzed by a chiral iodoarene precatalyst.

This paper provides a review of recent developments in the rapidly changing and advancing field of textile-based flexible pressure sensors. It summarizes the basic principles and approaches employe...

Atmospheric methane (CH 4 ) is a potent greenhouse gas that is strongly influenced by several human activities. China, as one of the major agricultural and energy production countries, contributes considerably to the global anthropogenic CH 4 emissions by rice cultivation, ruminant feeding, and coal production. Understanding the characteristics of China's CH 4 emissions is necessary for interpreting source contributions and for further climate change mitigation. However, the scarcity of data from some sources or years and spatially explicit information pose great challenges to completing an analysis of CH 4 emissions. This study provides a comprehensive comparison of China's anthropogenic CH 4 emissions by synthesizing the most current and publicly available datasets (13 inventories). The results show that anthropogenic CH 4 emissions differ widely among inventories, with values ranging from 44.4–57.5 Tg CH 4 yr −1 in 2010. The discrepancy primarily resulted from the energy sector (27.3 %–60.0 % of total emissions), followed by the agricultural (26.9 %–50.8 %) and waste treatment (8.1 %–21.2 %) sectors. Temporally, emissions among inventories stabilized in the 1990s but increased significantly thereafter, with annual average growth rates (AAGRs) of 2.6 %–4.0 % during 2000–2010 but slower AAGRs of 0.5 %–2.2 % during 2011–2015, and the emissions became relatively stable, with AAGRs of 0.3 %–0.8 %, during 2015–2019 because of the stable emissions from the energy sector (mainly coal production). Spatially, there are large differences in emissions hotspot identification among inventories, and incomplete information on emission patterns may mislead or bias mitigation efforts for CH 4 emission reductions. The availability of detailed activity data for sectors or subsectors and the use of region-specific emission factors play important roles in understanding source contributions and reducing the uncertainty in bottom-up inventories. Data used in this article are available at https://doi.org/10.6084/m9.figshare.12720989 (Lin et al., 2021).

As a novel detection method of CuSO4, terahertz (THz) spectroscopy detection has great application prospects, but the terahertz detection with the tablet method has low sensitivity, and with the metamaterials has complicated manufacture. This work has proposed a high-sensitivity pesticide THz spectroscopic detection method with a novel metal grating. The metal grating was composed of a circular hole array. It was made by laser micromachining technology to provide a simplified but improved measurement and had a strong transmission peak at the 0.4–1.0 THz band. The results indicated that the addition of copper sulfate (CuSO4) solutions to different concentrations caused the transmission peak frequency to shift red. The detection limit was about 103 times higher than that of CuSO4 measured on the polyethylene (PE) film substrate, which reached 0.375 mg/L. The method was applied for detecting CuSO4 in apple and grape, and the relative error was less than 5.8%. The metal grating combined with Terahertz time-domain spectroscopy (THz-TDS) can improve the sensitivity of sample detection and realize the detection and analysis of trace elements.

Bastnasite is widespread in alkali granite, carbonatite and REE ore deposits. The U-Th-Pb ages of bastnasite can constrain the mineralization age. Currently, the lack of suitable in situ analysis reference material is the major obstacle of bastnasite U-Th-Pb geochronology. In this study, the matrix effects of U-Pb and Th-Pb age determination in bastnasite using glass NIST 610 as the external calibration reference were evaluated with the 193-nm excimer LA-ICP-MS analysis in normal and additional gases laser ablation modes. The obtained U-Th-Pb ages of bastnasite were approximately 7–11% lower than their reference values in the normal analytical mode (without additional gas). Fortunately, the determined systematic age biases in U-Th-Pb dating were significantly reduced (less than 1–2%) with the addition of water vapor within the ablation chamber. This reduction may be attributed to the observed significant suppression of 206Pb/238U and 208Pb/232Th downhole fractionation in both NIST 610 glass and bastnasite by introducing a small quantity of water vapor in the ablation chamber. In addition, the obtained 206Pb/238U and 208Pb/232Th ages of bastnasite K-9, LZ1384, and MAD809 showed great consistency with their corresponding recommended values. The obtained results show that accurate and precise U-Th-Pb ages of bastnasite can be simultaneously obtained by using glass NIST 610 as the primary calibration standard in 193-nm LA-ICP-MS with the water vapor-assisted method. This simple and effective water vapor-assisted non-matrix-matched laser ablation method helps to promote the geological application of bastnasite U-Th-Pb geochronology.

As a two-dimensional semiconductor with many physical properties, including, notably, layer-controlled electronic bandgap and coupled spin-valley degree of freedom, monolayer MoSe2 is a strong candidate material for next-generation opto- and valley-electronic devices. However, due to substrate effects such as lattice mismatch and dielectric screening, preserving the monolayer's intrinsic properties remains challenging. This issue is generally significant for metallic substrates whose active surfaces are commonly utilized to achieve direct chemical or physical vapor growth of the monolayer films. Here, we demonstrate high-temperature-annealed Au foil with well-defined (100) facets as a weakly interacting substrate for atmospheric pressure chemical vapor deposition of highly crystalline monolayer MoSe2. Low-temperature scanning tunneling microscopy/spectroscopy measurements reveal a honeycomb structure of MoSe2 with a quasi-particle bandgap of 1.96 eV, a value comparable with other weakly interacting systems such as MoSe2/graphite. Density functional theory calculations indicate that the Au(100) surface exhibits the preferred energetics to electronically decouple from MoSe2, compared with the (110) and (111) crystal planes. This weak coupling is critical for the easy transfer of monolayers to another host substrate. Our study demonstrates a practical means to produce high-quality monolayers of transition-metal dichalcogenides, viable for both fundamental and application studies.

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), has become an important pest in Chinese agricultural systems since its invasion on 11 December 2018. After its establishment, FAW months in the year-round breeding region have become the main source population migrating to other areas in China. Field investigations were conducted in tropical and subtropical regions to improve understanding of its year-round breeding area in China. The results showed that FAW larval density was significantly correlated with the seasonal temperature of the location surveyed. The FAW larvae maintained a high density in the tropical area and were frequently found in sites of the south subtropical region, but were absent from the north subtropical region and the northern part of the central subtropical region. These results indicated that FAW can reproduce annually in the tropical and south subtropical regions of China, including Hainan, Taiwan and the southern area of Fujian, Guangdong, Guangxi, Guizhou, and Yunnan. Hence, great effort should be made to monitor and control FAW in the year-round breeding region to suppress the population density of this area and to reduce migration of moths into northern parts of China. This study clarifies the occurrence area of the pest in winter in China and provides much valuable information for its population forecasting and management.