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In this work, organic-inorganic hybrid ultrathin transparent films (UTFs), produced by layer-by-layer (LBL) assembly of the europium inclusion complex of -cyclodextrin (-CD) and Mg-Al-layered double hydroxide (MgAl-NO3-LDHs) nanosheets, are reported. UV-visible (UV-Vis) absorption and fluorescence spectroscopy show orderly growth of the europium inclusion complex of -CD/layered double hydroxide (EICC/LDH) films with an increasing number of deposition cycles. X-ray diffraction and scanning electron microscopy measurements indicate that the films feature periodic layered structures with uniform surface morphology. Moreover, when EICC is assembled with inorganic rigid LDH nanosheets, the lifetimes are prolonged due to the isolation effect, and the UTFs are transparent with high brightness, which indicate that these films could serve as new optical materials. Transparent and high-brightness fluorescent ultrathin films (UTFs) were fabricated via layer-by-layer assembly deposition of europium inclusion of -cyclodextrin (EICC) and MgAl-NO3- layered dual hydroxide (LDH) nanosheets. EICC was assembled with inorganic rigid LDH nanosheets, which prolonged the lifetimes. The UTF showed a periodic long-range ordered and regular structure and tunable red emission intensity. These hybrid films have considerable potential for applications in the design of various LDH-based optical devices. [ABSTRACT FROM AUTHOR]

This work investigates the decadal modulation of the El Niño-Southern Oscillation (ENSO)-East Asian winter monsoon (EAWM) relationship by the Atlantic Multidecadal Oscillation (AMO). A stable ENSO-EAWM relationship is found during the positive AMO phase but not during the negative phase. While the impact of El Niño events on the EAWM does not depend on the AMO phase, a different picture is observed for La Niña events. The La Niña boreal winter season coincides with a strengthened EAWM during a positive AMO phase and a weakened EAWM during a negative AMO phase. We suggest that the AMO's modulating effect mainly comprises two pathways that influence ENSO's impact on the EAWM. On one hand, when La Niña coincides with a positive AMO, the warm SST anomalies over the western North Pacific (WNP) are amplified both in intensity and spatial extent, which favors strengthened WNP cyclonic anomalies and an enhanced EAWM. During La Niña with a negative AMO, only very weak SST anomalies occur over the WNP with reduced WNP cyclonic anomalies that are confined to the tropics, thus having little effect on the EAWM. On the other hand, an eastward-propagating Rossby wavetrain across the mid-high latitudes of Eurasia during a warm AMO phase strengthens the Siberian high and thus leads to a strengthened EAWM, while during a cold AMO phase the Siberian high is weakened, leading to a reduced EAWM. In contrast, El Niño and its associated atmospheric responses are relatively strong and stable, independent of the AMO phase. These results carry important implications to the seasonal-to-interannual predictability associated with ENSO. [ABSTRACT FROM AUTHOR]

We report a facile combustion method synthesis of reduced graphene oxide/CuI composites as a photocatalyst, in which CuI nanoparticles were homogeneously distributed on the surface of reduced graphene oxide (rGO), showing a good visible light response. The rGO-supported and unsupported CuI hybrids were tested over the photocatalytic reduction of CO 2 for methanol evolution in visible light. In the current study rGO-CuI composites have shown excellent yields (19.91 μmol g-cat −1 ). rGO provides a light-weight, charge complementary and two-dimensional material that interacts effectively with the CuI nanoparticles. [ABSTRACT FROM AUTHOR]

Narrow band-gap conjugated polyelectrolytes (NBGCPs) combine the advantages of narrow band-gap conjugated polymers and polyelectrolytes. However, they are limited reported and seldom used in polymer solar cells (PSCs). Herein, we design and synthesized two PTB7-based NBGCPs, cationic PTB7-NBr and zwitterionic PTB7-NSO 3 , as cathode interlayers (CILs) in conventional PSCs. Compared to poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2- b :4,5- b′ ]dithiophene-2,6-diyl- alt -ethylhexyl-3-fuorothithieno[3,4- b ]thiophene-2-carboxylate-4,6-diyl] (PTB7), both PTB7-NBr and PTB7-NSO 3 have similar absorption while PTB7-NBr has a higher HOMO level than PTB7 and PTB7-NSO 3 . With PTB7-NBr and PTB7-NSO 3 as CIL and Al as cathode, the devices both exhibited high efficiencies. The optimal power conversion efficiencies (PCEs) of PTB7-NBr device and PTB7-NSO 3 device are about 9%. However, PTB7-NBr devices are less sensitive to the CIL film thicknesses and the PCEs of PTB7-NSO 3 device decrease sharply when the thickness of PTB7-NSO 3 over 3 nm. What's more, when the devices with an Ag cathode PTB7-NBr exhibits a much better interfacial modification than PTB7-NSO 3 . Ultraviolet photoelectron spectroscopy (UPS) indicate that the work functions of PTB7-NBr and PTB7-NSO 3 film on Al are identical while on Ag they are different. We suggest the insensitivity to CIL thickness and good performance for Ag device of PTB7-NBr devices are attributed to the bromide anions in PTB7-NBr. The report on PTB7-based NBGCPs broads the types of organic cathode interfacial materials and is beneficial to the deep insight of ionic effect in electrolyte materials. [ABSTRACT FROM AUTHOR]

Tryptophan dimers (TDs) are an important class of natural products with diverse bioactivities and share conserved biosynthetic pathways. We report the identification of a partial gene cluster ( spm) responsible for the biosynthesis of a class of unusual TDs with non-planar skeletons including spiroindimicins (SPMs), indimicins (IDMs), and lynamicins (LNMs) from the deep-sea derived Streptomyces sp. SCSIO 03032. Bioinformatics analysis, targeted gene disruptions, and heterologous expression studies confirmed the involvement of the spm gene cluster in the biosynthesis of SPM/IDM/LNMs, and revealed the indispensable roles for the halogenase/reductase pair SpmHF, the amino acid oxidase SpmO, and the chromopyrrolic acid (CPA) synthase SpmD, as well as the positive regulator SpmR and the putative transporter SpmA. However, the spm gene cluster was unable to confer a heterologous host the ability to produce SPM/IDM/LNMs. In addition, the P450 enzyme SpmP and the monooxygenase SpmX2 were found to be non-relevant to the biosynthesis of SPM/IDM/LNMs. Sequence alignment and structure modeling suggested the lack of key conserved amino acid residues in the substrate-binding pocket of SpmP. Furthermore, feeding experiments in the non-producing Δ spmO mutant revealed several biosynthetic precursors en route to SPMs, indicating that key enzymes responsible for the biosynthesis of SPMs should be encoded by genes outside of the identified spm gene cluster. Finally, the biosynthetic pathways of SPM/IDM/LNMs are proposed to lay a basis for further insights into their intriguing biosynthetic machinery. [ABSTRACT FROM AUTHOR]

• Honeycomb-like ONS-HPC-0.5 is obtained via pre-treatment and carbonization. • This material owns hierarchical porous structure with heteroatoms O/N/S codoped. • The assembled symmetric supercapacitor exhibits superior capacitance behavior. To achieve carbon peaking and carbon neutrality, it is important to develop a circular economy. Among them, the pollution control of solid waste is a key direction. Herein, an environmentally-friendly method has been proposed to convert the discarded industrial polyphenylene sulfide (PPS) non-woven fabric fiber into value-added hierarchical porous carbon (HPC) for superior performance supercapacitor. Pre-treatment by oxidation and nitrification, combined with activation process and carbonization, the well-organized honeycomb-like carbon material ONS-HPC-0.5 is obtained with the ultrahigh specific surface area (3112.2 m2 g−1), abundant heteroatoms oxygen (10.85 atom%), nitrogen (4.93 atom%) and sulfur (5.33 atom%) codoped and hierarchical porous structure. Owing to the structure advantages, the ONS-HPC-0.5 electrode delivers high specific capacitance of 301 F g−1 at 0.5 A g−1, superior rate characteristic and electrochemical stability in alkaline electrolyte. Notably, the assembled ONS-HPC-0.5//ONS-HPC-0.5 symmetric supercapacitor achieves the remarkable energy density of 21.87 Wh kg−1 with power density of 450 W kg−1, which not only demonstrates this material promising application in supercapacitor industry, but also opens up a new circular economy model for the recycling of industrial solid waste. [Display omitted] This material not only demonstrates promising application in supercapacitor industry, but also opens up a new circular economy model for the recycling of industrial solid waste. [ABSTRACT FROM AUTHOR]

As the dominant form of mesoscale variability in the equatorial eastern Pacific, Tropical Instability Waves (TIWs) are known to interact with the El Niño and Southern Oscillation (ENSO) in complex ways. TIWs activity is modulated by the ENSO state and also provide significant feedback on ENSO via nonlinear dynamic heating (NDH), acting as a source of asymmetry between the El Niño and La Niña phases. In this work, we show that the interannual variability of TIWs-induced heat flux and NDH can be approximately expressed in terms of the mean meridional temperature gradient as TIWs tend to transport heat downgradient of the temperature anomalies along the Sea Surface Temperature (SST) front. The TIWs-induced NDH can be quantified as an asymmetric negative feedback on ENSO by a nonlinear thermal eddy diffusivity which depends on the background TIWs pattern and the ENSO-related linear and nonlinear processes. This proposed parameterization scheme can capture well the direct ENSO modulation on TIWs activity, the combination effect arising from the nonlinear interaction between ENSO and the cold tongue annual cycle, and associated ENSO nonlinearity. This parameterization scheme is effectively tested using four ocean reanalysis datasets with different horizontal resolutions that exhibit contrasted patterns of TIWs activity. This scheme may be useful for assessing the TIWs-induced feedback on ENSO in mechanistic ENSO models to better understand the dynamics of ENSO complexity. [ABSTRACT FROM AUTHOR]

The electrocatalytic CO2 reduction reaction (CO2RR) has been considered a promising route toward carbon neutrality and renewable energy conversion. At present, most bismuth (Bi) based electrocatalysts are adopted to reduce CO2 to formate (HCOOH). However, the mechanism of different Bi nanostructures on the electrocatalytic performance requires more detailed exposition. Herein, a combined chemical replacement and electrochemical reduction process is reported to realize in situ morphology reconstruction from Bi@Bi2O3 nanodendrites (Bi@Bi2O3‐NDs) to Bi nanoflowers (Bi‐NFs). The Bi@Bi2O3‐NDs are proven to undergo a two‐step transformation process to form Bi‐NFs, aided by Bi2O2CO3 as the intermediate in KHCO3 solution. Extensive surface reconstruction of Bi@Bi2O3‐NDs renders the realization of tailored Bi‐NFs electrocatalyst that maximize the number of exposed active sites and active component (Bi0), which is conducive to the adsorption and activation of CO2 and accelerated electron transfer process. The as‐prepared Bi‐NFs exhibit a Faradaic efficiency (FEformate) of 92.3% at −0.9 V versus RHE and a high partial current density of 28.5 mA cm−2 at −1.05 V versus RHE for the electroreduction of CO2 to HCOOH. Moreover, the reaction mechanism is comprehensively investigated by in situ Raman analysis, which confirms that *OCHO is a key intermediate for the formation of HCOOH. [ABSTRACT FROM AUTHOR]

It is a huge challenge to synthesize high luminescent performance of graphene oxide-rare earth hybrid materials, due to the strong quenching effect of graphene oxide. Herein we reveal a novel graphene oxide/rare-earth complexes hybrid materials that the Eu 3+ -2-thenoyltrifluoroacetone (TTA)-pyromellitic acids (PMA) were deposited on the surface of graphene oxide sheets (GOSs) via noncovalent approach between GOSs and PMA. This materials exhibit stronger luminescence intensity, longer decay lifetime and better thermal stability than pure Eu 3+ complexes. It is confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction and luminescent data. Moreover, we observed PMA plays a significant role in improving the luminescence intensity and prolonging the decay lifetime of hybrid materials. [ABSTRACT FROM AUTHOR]

UsingN-methyl-N-(1-phenyl)ethylcarbamoyl(trimethyl)silane as an amide source, the direct transformation of benzylic chlorides into the corresponding aryl acetamides through palladium-catalyzed aminocarbonylation is described. The electronic property and the relative position of substituents on the aromatic ring impact the coupling efficiency. [ABSTRACT FROM PUBLISHER]

A PTB7-based cationic narrow band-gap polyelectrolyte, named PTB7-NBr, has been designed and synthesized as a cathode interfacial material for polymer solar cells. PTB7-NBr exhibits excellent cathode interfacial modification in solar cells with PTB7 and PTB7-Th as donor polymer and a high PCE of 9.24% was achieved. [ABSTRACT FROM AUTHOR]

Diamond features an attractive combination of outstanding mechanical, optical, thermal and electrical properties; tunable surface characteristics; and unprecedented biocompatibility. Additionally, diamond can possess unique nitrogen–vacancy emission centers that are highly photostable and extremely sensitive to magnetic fields, temperatures, ion concentrations, and spin densities. With these inherent merits, diamond in various nanoscale configurations has demonstrated a variety of distinctive applications in a broad range of fields. In particular, research on diamond nanoparticles (0-dimensional structures) and arrays of diamond nanoneedles/nanowires (1-dimensional structures) has witnessed important and exciting progress in recent years. Here, we systematically review the superior properties of diamond nanomaterials and the nitrogen–vacancy centers they contain as well as their uses in biomedical applications, including biosensing, bioimaging and drug delivery. Moreover, systematic studies of the biocompatibility and toxicity of diamond nanostructures, which constitute an important issue for the biomedical applications of diamond that has not yet been thoroughly addressed in previous reviews, are also discussed. Finally, we present our insights into the key issues concerning these diamond nanomaterials and their future development for applications. [ABSTRACT FROM AUTHOR]

• A coal tar-based (CTB) collector is introduced in unburned carbon (UC) flotation. • The CTB collector increases the content of hydrophobic groups on the UC surface. • The adsorption characteristics of CTB collector on the UC surface are revealed. • The CTB collector shortens the liquid film thinning time on the UC surface. The unburned carbon (UC) in fly ash is a vital parameter that governs the further utilization of fly ash in mortar and concrete industry. Flotation is an effective methodology for removing the UC from fly ash. However, the specific physicochemical properties of the UC particle surface make them difficult to float. In this study, a coal tar-based (CTB) collector was used to remove the UC from fly ash through flotation process. The adsorption mechanism of the CTB collector and diesel on the UC particle surface was characterized by scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), molecular dynamics (MD) simulation, and induction time tests. The levels of oxygen-containing functional groups and aromatic ring compounds present in the CTB collector were considerably higher than those in diesel. The oxygen-containing functional group contents on the untreated UC surface, the diesel-treated UC surface, and the CTB collector-treated UC surface decreased in that order. The MD simulation results indicated that the aromatic compounds (dibenzofuran and naphthalene, etc.) in the CTB collector interacted strongly and adsorbed at deep locations with the UC surface compared to the alkanes (dodecane, diesel, etc.). The alkanes are indispensable as the collector in the fly ash flotation process and synergize with aromatic compounds to improve the mobility of water molecules on the UC surface. The CTB collector significantly enhanced the floatability of the UC particle and hence improved the flotation removal of UC from fly ash. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel C@Fe 2 O 3 /HCNFs nanocomposites with 3D sandwich-like structure was first fabricated for lithium-ion batteries. • The preparation process is very simple and requires no additives. • Unique sandwich-like structure could effectively enhances the electrochemical performance. • The as-acquired C@Fe 2 O 3 /HCNFs anode composite exhibited an excellent cycling stability. In this study, a novel carbon-coated Fe 2 O 3 /helical carbon nanofibers (C@Fe 2 O 3 /HCNFs) composite with 3D sandwich-like structure was first successfully synthesized through a facile two-step method and utilized as anode materials of lithium-ion batteries (LIBs). A carbon layer with a thickness of about 3–5 nm was uniformly coated on the surface of the C@Fe 2 O 3 /HCNFs composites, and Fe 2 O 3 nanoparticles with a particle size of about 5–20 nm was distributed between the carbon layer and HCNFs matrix. The C@Fe 2 O 3 /HCNFs anode shows excellent long-term cycle life and stability, and the discharge performance can reach 1298.6 mAh/g after 100 cycles at 200 mA/g, which is 59 % higher than that of Fe 2 O 3 /HCNFs anode. The electrochemical performance and stable structure of C@Fe 2 O 3 /HCNFs composites are improved due to the interaction between the carbon coating layers, HCNFs, and Fe 2 O 3 nanoparticles during the charge–discharge process. The present study reveals the potential application of C@Fe 2 O 3 /HCNFs as a novel anode material for LIBs.. [ABSTRACT FROM AUTHOR]

Risks associated with deepwater drilling are dynamic because of various accident-causing factors such as equipment failures, abnormal processes, and operator errors. All these factors should be considered during the implementation of dynamic and quantitative risk assessment (DQRA) for drilling operations. Dynamic Bayesian network (DBN) can graphically present the cause-effect relationships among different types of risk influencing factors (RIFs). Hence, this study developed a four-step DBN model for the DQRA of deepwater drilling. Firstly, multi-type contributing RIFs were identified according to the process flow. Subsequently, a network structure was developed to present the potential accident scenarios and capture the interdependencies among the RIFs. Thereafter, the probabilities of equipment failures, abnormal processes, and operator errors were determined using the probabilistic, data-based, and Standardized Plant Analysis Risk—Human Reliability Analysis (SPAR-H) approach, respectively. Finally, DBN inference was performed to evaluate the probabilistic risk of drilling operations. The model was applied to a case study of DQRA for managed pressure drilling (MPD), where the calculated initial blowout probability was 9.30 × 10−5, whereafter it was updated dynamically. This case study demonstrates the practicability of the proposed approach. This study contributes to a systematic investigation of the role of multisource data in DQRA using a full DBN approach. The assessment results can provide early warnings for practitioners to implement risk elimination or mitigation measures in real time. • A dynamic Bayesian network model is proposed to quantitatively assess deepwater drilling risks. • Probability distribution function is used to calculate equipment failure probabilities. • Data-based approach is used to deal with abnormal process probabilities. • SPAR-H is used to evaluate operator error probabilities. [ABSTRACT FROM AUTHOR]

• A 3D refined FEM was proposed to evaluate fire resistance of composite segment. • The bearing capacity of composite segment was detected at different temperatures. • The ductility of composite segmental joint may be greatly decreased due to fire. • A high-temperature interlayer appears owing to the different thermal conductivity. • The concrete damage was mainly caused by temperature rise and extra deformation. This paper developed a FEM modeling to evaluate the composite segmental lining's fire resistance by simulating the thermo-mechanical behavior under the fire conditions. The mechanical and thermal properties related to concrete and steel were selected and introduced in detail. FE models of the single composite segment, segmental joint, and the full segmental lining were then established in ABAQUS. The verification of the models was conducted compared with the results from three experiments. Based on the calibrated FE models, the bearing capacity was first investigated for all three models at normal temperature and after the fire. The temperature distribution and deformation modes were subsequently examined. An in-depth discussion was conducted on the concrete damage and the corresponding protection methods. A comparison was finally carried out to detect the fire resistance between the plain concrete segment and the composite segment. The results showed that both the bearing capacity and the composite segmental joint's flexibility might significantly decrease due to the fire loading. The concrete damage was mainly caused by the rising temperature and the corresponding deformation of the whole lining ring with the expansion of different components during the fire. The restraint provided by the covered steel plates to the concrete inside led to the enhancement of the fire resistance for the composite segment. The proposed FEM model can be applied to simulate the thermo-mechanical behavior of other types of composite structures with reasonable material properties. [ABSTRACT FROM AUTHOR]

Surging energy consumption and environmental concerns have stimulated interest in the production of chemicals and fuels through sustainable and renewable approaches. Fatty acid-based hydrocarbons, such as alkanes and alkenes, are of particular interest to directly replace fossil fuels. Towards this effort, understanding of hydrocarbon-producing enzymes is the first indispensable step to bio-production of hydrocarbons. Here, we review recent advances in the discovery and mechanistic study of enzymes capable of converting fatty acid precursors into hydrocarbons, and provide perspectives on the future of this rapidly growing field. [ABSTRACT FROM AUTHOR]

This study aimed to develop and validate a simple and sensitive ultra high performance liquid chromatography tandem mass spectrometry method for the simultaneous determination of sophoraflavanone G and kurarinone in rat plasma by using rutin as the internal standard. Then, the developed method was applied to investigate the pharmacokinetics of sophoraflavanone G and kurarinone in rats after dosing the flavonoid extract from Sophora flavescens. Plasma samples were processed using a liquid-liquid extraction procedure with ethyl acetate. The analysis was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring with an electrospray ionization source in negative ionization mode. Quantitative ion transitions of m/z 423.2→161.2, 437.2→161.1, and 609.3→300.3 were monitored for sophoraflavanone G, kurarinone, and rutin, respectively. The calibration curves of the two analytes exhibited good linearity ( r2>0.9923) over the range of 0.1-200 ng/mL for sophoraflavanone G and 0.1-1000 ng/mL for kurarinone. Relative standard deviations were less than 13.2% for the intra- and inter-day precisions and no more than 12.6% for the recovery, showing good precision and satisfactory accuracy of the developed method. The validated method was successfully applied to the pharmacokinetic study of sophoraflavanone G and kurarinone after a single intravenous (25 mg/kg) and oral (500 mg/kg) administration of the flavonoid extract from S. flavescens, and the absolute bioavailability for sophoraflavanone G and kurarinone was about 36 and 17%, respectively. [ABSTRACT FROM AUTHOR]

Enantioselectivity in ecotoxicity, digestion and uptake of chiral pesticide cyproconazole to Chlorella pyrenoidosa was studied. The 96h-EC 50 values of rac- and the four enantiomers were 9.005, 6.616, 8.311, 4.290 and 9.410 mg/L, respectively. At the concentrations of 8 mg/L and 14 mg/L, the contents of pigments exposed in rac-, enantiomer-2 and 4 were higher than that exposed in enantiomer-1 and 3. The superoxide dismutase (SOD) and catalase (CAT) activity of algae exposed to enantiomer-1 and 3 was higher than that exposed to the rac-, enantiomer-2 and 4 at three levels. In addition, the malondialdehyde (MDA) concentrations in algae disposed with enantiomer-1 and 3 were increased remarkably at three levels. For the digestion experiment, the half-lives of four enantiomers in algae suspension were 28.06, 19.10, 21.13, 15.17 days, respectively. During the uptake experiment, the order of the concentrations of cyproconazole in algae cells was enantiomer-4, 2, 3 and 1. Based on these data, we concluded that ecotoxicity, digestion and uptake of chiral pesticide cyproconazole to C. pyrenoidosa were enantioselective, and such enantiomeric differences must be taken into consideration when assessing the risk of cyproconazole to environment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption and electronic properties of gases on nanoporous CN monolayer were studied. • NO, SO 2 , H 2 S, and NH 3 molecules are weakly chemisorbed on the monolayer. • Adsorption of NO, H 2 S and NH 3 efficiently tunes electronic properties of CN monolayer. • CN monolayer has high sensitivity and selectivity to NO, H 2 S and NH 3 with moderate recovery time. • CN monolayer as a good candidate for NO, H 2 S, NH 3 gas sensors at room temperature. To explore the possibility of the nanoporous CN (p-CN) monolayers as high-performance gas sensors, the adsorption, electronic properties and gas-sensing performance of various gases on the p-CN monolayers have been studied by first-principles methods. Only NO, SO 2 , H 2 S and NH 3 have weak chemisorption on the monolayer, which and the physical adsorption of NO 2 and C 2 H 4 changed efficiently the electronic properties and work function of p-CN monolayer. The p-CN monolayer towards NO, NH 3 , and H 2 S gases has comparatively high sensitivity, while has quite low sensitivity towards other gases. The characteristics on the I-V curves and work function can effectively distinguish various gases. The recovery time for NO, NH 3 , and H 2 S is about 4.1 s, 0.27 s, and 0.018 s at 300 K, respectively, which is fairly moderate for the reuse of the CN-based sensor for NO, NH 3 , and H 2 S detection. However, the over-short (or over-long) recovery time for NO 2 and C 2 H 4 (<10−6 s) (or SO 2 , c. 35 min) gravely hinders the p-CN-based gas sensors for these gases monitoring. Therefore, the p-CN monolayers as reusable gas sensors have high sensitivity and selectivity at room temperature for NO, H 2 S and NH 3 detection. [ABSTRACT FROM AUTHOR]

Organic constituents of atmospheric particular matter (PM) contribute significantly to prompt generation of reactive oxygen species (ROS) in particle phase, which is often quantified in terms of its oxidative potential (OP). In this study, we used complementary methods of the advanced molecular characterization and the OP quantitation to explore potential of different organic species to enhance ROS generation in ambient aerosol samples. We used seven PM 2.5 samples collected in the Midwest US, and extracted them sequentially into a set of solvents with different polarity: first non-polar hexane (HEX), then moderately polar dichloromethane (DCM) and finally polar deionized (DI) water. The DI extracts were further separated using solid phase extraction to isolate water-soluble organic carbon (WSOC) from inorganic ions. The OP of obtained extracts was analyzed using dithiothreitol (DTT) assay and reported here in terms of the DTT consumption rate (called DTT activity). The molecular composition of the same extracts was analyzed using a tandem platform of high-performance liquid chromatography (HPLC) coupled with a photodiode array detector (PDA) and a high-resolution mass spectrometer (HRMS). Highest DTT activities were observed in WSOC fractions (>1.1 μM min−1) followed by DCM (0.75–1.1 μM min−1) and HEX (<0.75 μM min−1) fractions, respectively. These results were complemented by the HPLC-PDA-HRMS molecular characterization data indicating numerous redox-active polar organics detected in the WSOC fractions. In particular, chemical component with elemental formula of C 11 H 11 N - attributed to dimethyl quinoline (DMQ) - was found systematically across all DTT-active fractions. The unprotonated nitrogen atom in the pyridine ring of quinolines facilitates electron transfer in the redox reactions, catalyzing generation of ROS in the quinoline containing samples. This is the first study that unambiguously identifies quinoline as a promoter of ROS generation determined within complex mixtures of ambient organic aerosols. [Display omitted] • Ambient PM2.5 samples were collected in Midwest USA for quantitative analysis of their oxidative potential. • The molecular composition of the PM2.5 samples was analyzed using advanced methods of high-resolution mass spectrometry. • N-containing heterocyclic compounds enhance oxidative potential of PM2.5 organic components. [ABSTRACT FROM AUTHOR]

Morphology control and multi-elemental doping are considered two effective strategies to improve the photocatalytic performance of graphitic carbon nitride (g-C 3 N 4). Herein, a mild and convenient method was applied to synthesize S/Cd co-doped g-C 3 N 4 nanorods with excellent photocatalytic performance. Under visible irradiation, the optimized sample could degrade 89.7 % methylene blue (MB) in 50 min and 96.5 % rhodamine B (RhB) in 15 min, whose degradation rates were 2.2 times and 23.2 times higher than that of pristine g-C 3 N 4 , respectively. Comprehensive investigation revealed that the presence of nanorods and co-doping of S and Cd led to a larger specific surface area, more nitrogen vacancies, and modification of band structure, which could considerably enhance the photocatalytic performance. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Ppy-Ag 3 PO 4 /AgCl@PAL (PAAP) was synthesized by a simple co-precipitation approach. • PAAP shows Pickering emulsification-photodegradation synergistic remediation for oil pollution. • The introduction of Ppy and AgCl effectively inhibited the photocorrosion of Ag 3 PO 4. • PAAP exhibited excellent photocatalytic activity and reusability under visible light. • Pickering emulsification and photodegradation mechanism of diesel were proposed. The frequent occurrence of marine oil spill accidents has brought great negative influence on the ecological environment and human development. In this study, polypyrrole-Ag 3 PO 4 /AgCl@Palygorskite (PAAP) was successfully synthesized by a simple co-precipitation approach and then it was used to realize the dual remediation of marine oil pollution based on Pickering emulsion-based photocatalytic technology. Here, palygorskite (PAL) functions as an effective Pickering emulsion stabilizer to disperse oil pollutants. In virtue of the dispersion of PAL, Ag 3 PO 4 -based photocatalyst is able to fully contact with the oil droplets, thus leading to a greatly improved photocatalytic degradation performance for oil pollution. PAAP-stabilized Pickering emulsion showed good stability in 7 days, which provided enough time for the subsequent oil photodegradation. The photocorrosion of Ag 3 PO 4 was significantly alleviated by the introduction of polypyrrole and AgCl. Thus, the photocatalytic activity and reusability of PAAP were greatly enhanced compared with Ag 3 PO 4 @PAL. Additionally, this study explored the influence of illumination time, PAAP amount and environmental factors (such as salinity and wave fluctuations) on the emulsification-photocatalytic remediation ability of PAAP. Importantly, it was found that intermittent agitation could increase the removal of diesel greatly. Finally, the photocatalytic reaction mechanism and the possible diesel degradation pathways were analyzed through a series of experimental investigations. [ABSTRACT FROM AUTHOR]

• The full-scale structural test of super large diameter shield tunnel was conducted. • The mechanical properties of the key segment and its adjacent area were studied. • The damage process of the key segment was analyzed. • The failure mechanism of the key segment was interpreted. Due to the size effect and the change of joint design, the mechanical behavior of the shield tunnel with super-large cross-section is different from that of the conventional medium and large section tunnel. In addition, the mechanical and failure characteristics of the key segment are different from those of other segments in shield tunnels due to its unique shape and weaker stiffness. In this paper, a series of full-scale experiments were carried out to investigate the failure characteristics of the key segment in the shield tunnel with a super-large cross-section under general loading. The safety state of the whole structure was quantitatively evaluated based on the obtained bearing capacity, deformation characteristics, and progressive damage features. The testing procedure was introduced in detail, including the examined specimen, measurements, and loading conditions based on a revisit to the prototype. A multi-functional three-dimensional loading system was adopted to apply a compression-bending load similar to that in practice on the testing specimen. In-depth discussions were conducted on the displacement, joint opening, joint dislocation, and the failure characteristics of the segments directly recorded and observed during the tests. The results show that the longitudinal force acting along the tunnel axis significantly limits the inward convergence of segments, the opening of circumferential joints, and the dislocation of longitudinal and circumferential joints in a specific range. Under general loading conditions, when the load reaches the most unfavorable load combination, the testing segments are still in a safe state, whose deformation does not exceed the design requirements, and no damage occurs. After reaching the destructive load, distinct crack propagation behavior is found in different stages, which can be divided into four steps according to the observed distribution characteristics. The final failure of the segments begins with the collapse of the longitudinal joint compression zone. Additionally, the reverse shear circumferential joint is seriously damaged, whereas the forward shear circumferential joint is only slightly damaged. The results can provide novel insights into the failure characteristics of the key segment in the super-large cross-section tunnel. [ABSTRACT FROM AUTHOR]

In this paper, porous Fe–CeO 2 with abundant oxygen vacancies was prepared by calcination of hexagonal bipyramidal prussian blue analogue (CeFe-PBA), and then CeO 2 @NiFe-LDH composite was synthesized by hydrothermal method. The morphology of the composite remain roughly cubic and biconical. The loading of LDH makes the surface of the cube grow abundant nanosheets. The synergistic effect of porous materials and nanosheets can improve the properties of the composites. The specific capacitance of the material is 516.524 F g−1 at 1 A g−1. At the same time, the capacitance retention can reach 83.442% after 5000 cycles. In particular, asymmetric supercapacitors (ASC) of CeO 2 @NiFe-LDH//AC have outstanding energy density (21.167 Wh kg−1) and high power density (7500 W kg−1). [ABSTRACT FROM AUTHOR]

Several studies have found that IDH-prone patients have higher baseline plasma angiotensin II levels than those who are IDH-resistant, and activation of the RAAS is known to be involved in LVH development, independent of afterload [[3]]. Dear Sir, We have read with great interest the paper entitled 'High ultrafiltration rate induced intradialytic hypotension is a predictor for cardiac remodeling: a 5-year cohort study' by Yu et al. [[1]]. [Extracted from the article]

The wintertime Arctic Oscillation (AO) manifests a high degree of uncertainty in its spatial structure, which was suggested to be associated with some other extratropical atmospheric variabilities (e.g., the Aleutian-Icelandic Low seesaw and the stratospheric polar vortex). Based on reanalysis and model simulation data in 1950–2019, the present work investigates the possible effects of El Niño-Southern Oscillation (ENSO) on the AO spatial structure. It is found that there exist obvious differences in AO structure between early (November–December) and late (January–February) winter. In early winter, the AO is manifested by its traditional pattern with three action centers, one of which is over the Arctic and the other two are with the opposite sign over the North Atlantic and North Pacific. However, the AO pattern in late winter changes remarkably, resembling a regional North Atlantic Oscillation (NAO) pattern with the absence of its significant Pacific center. The noteworthy sub-seasonal variation in the AO spatial pattern can be largely ascribed to the observed fact that ENSO atmospheric teleconnections to the Northern Hemisphere are significantly enhanced in late winter compared with early winter. The enhanced ENSO-associated teleconnection during late winter can significantly weaken the teleconnectivity of the Arctic center with the Pacific center, resulting in the absence of the AO’s significant Pacific center. The understanding of ENSO impacts on the AO structure has some significance for the AO-associated climate prediction around the North Pacific region. [ABSTRACT FROM AUTHOR]

Co 3 O 4 /HCNFs were firstly prepared successfully via a simple and inexpensive oil-bath method. Within the hybrid composite, the HCNFs and Co 3 O 4 show a synergistic effect to improve the specific capacity and cycling stability of Lithium-ion batteries. [Display omitted] • A novel Co 3 O 4 /HCNFs anode composite was first introduced for lithium-ion batteries. • A simple two-step approach was successfully used to prepare the Co 3 O 4 /HCNFs composite material. • Co 3 O 4 /HCNFs composites make an obvious advantage as an anode material for lithium-ion batteries. In the current work, the Co 3 O 4 /helical carbon nanofibers (Co 3 O 4 /HCNFs) composite was successfully obtained by using a simple and inexpensive two-step method and applied as an anode material for lithium-ion batteries (LIBs). The results showed that Co 3 O 4 nanoparticles (the nanoparticle size of 10–20 nm) were anchored on the surface of helical carbon nanofibers. The Co 3 O 4 /HCNFs anode displays an excellent cyclability of 853 mAh/g after 200 cycles under the current density of 200 mA/g (327.7 %, 183.7 %, and 172.0 % higher than the pure HCNFs, pure Co 3 O 4 , and Co 3 O 4 -HCNFs respectively). The superior electrochemistry capability of the Co 3 O 4 /HCNFs composites are mainly thankful to the specific 3D helical structure of HCNFs, which can not only accommodate the volume expansion of nano-Co 3 O 4 during charge–discharge process, but also greatly enhance the conductivity of Co 3 O 4. Therefore, this research provides a novel method to exploiting an excellent and stable anode material for enhanced LIBs. [ABSTRACT FROM AUTHOR]

Excitation dependent luminescent materials, which have attracted significant scientific attention in the field of information security owing to information storage and luminescence properties. However, it remains a formidable challenge in developing excitation dependent luminescent materials with a simple synthesis method and predictably modulated luminescent outputs. Herein, a novel Ln3+/Fluorescent dyes@MOFs strategy is developed to generate excitation dependent continuous color-changing luminescent materials via a hydrothermal method and post-synthetic modification (PSM), based on metal-organic frameworks (MOFs) matrix doped with lanthanide cations and fluorescent dyes encapsulated into the lanthanide MOFs. The continuous proportional emission of mixed luminescence appeared within a single matrix in response to the different excitation wavelength and the proportional emission control (PEC) mechanism between the two luminescent centers is proposed. In addition, the photoluminescence platform demonstrates a distinct security method based on covert color that are controlled by distinct excitation wavelengths and excellent luminescence stability have also been verified in these new materials. • Ln3+/Hoc@UIO-66(DPA) achieve excitation wavelength-dependent continuous color-tunable luminescence in a single mixture. • Proportional emission control (PEC) mechanism is proposed. • Ln3+/Hoc@UIO-66(DPA) (Ln = Eu, Tb) materials have potential applications in the field of anticounterfeiting. • The materials are acid and alkali resistant, have high thermal stability, and can be multi-functional luminescent. [ABSTRACT FROM AUTHOR]

A thiolated pH-responsive DNA conjugated gold nanorod (GNR) was developed as a multifunctional nanocarrier for targeted, pH-and near infrared (NIR) radiation dual-stimuli triggered drug delivery. It was further passivated by a thiolated poly(ethylene glycol)-biotin to improve its cancer targeting ability by specific binding to cancer cell over-expressed biotin receptors. Doxorubicin (DOX), a widely used clinical anticancer drug, was conveniently loaded into nanocarrier by intercalating inside the double-stranded pH-responsive DNAs on the GNR surface to complete the construction of the multifunctional nanomedicine. The nanomedicine can rapidly and effectively release its DOX payload triggered by an acidic pH environment (pH ~ 5) and/or applying an 808 nm NIR laser radiation. Compared to free DOX, the biotin-modified nanomedicine displayed greatly increased cell uptake and significantly reduced drug efflux by model multidrug resistant (MDR) breast cancer cell lines (MCF-7/ADR). The application of NIR radiation further increased the DOX release and facilitated its nuclear accumulation. As a result, this new DNA-GNR based multifunctional nanomedicine exerted greatly increased potency (~ 67 fold) against the MDR cancer cells over free DOX. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the Indo-Pacific atmospheric response to ENSO comprises two dominant modes of variability: a meridionally quasi-symmetric response (independent of the annual cycle) and an antisymmetric response (arising from the nonlinear atmospheric interaction between ENSO variability and the annual cycle), referred to as the combination mode (C-mode). This study demonstrates that the direct El Niño signal over the tropics is confined to the equatorial region and has no significant impact on the atmospheric response over East Asia. The El Niño-associated equatorial anomalies can be expanded toward off-equatorial regions by the C-mode through ENSO's interaction with the annual cycle. The C-mode is the prime driver for the development of an anomalous low-level anticyclone over the western North Pacific (WNP) during the El Niño decay phase, which usually transports more moisture to East Asia and thereby causes more precipitation over southern China. An atmospheric general circulation model is used that reproduces well the WNP anticyclonic anomalies when both El Niño sea surface temperature (SST) anomalies as well as the SST annual cycle are prescribed as boundary conditions. However, no significant WNP anticyclonic circulation anomaly appears during the El Niño decay phase when excluding the SST annual cycle. The analyses herein of observational data and model experiments suggest that the annual cycle plays a key role in the East Asian climate anomalies associated with El Niño through their nonlinear atmospheric interaction. Hence, a realistic simulation of the annual cycle is crucial in order to correctly capture the ENSO-associated climate anomalies over East Asia. [ABSTRACT FROM AUTHOR]

A novel solid fluorescent sensor with millimeter size, based on graphene quantum dots/polystyrenic anion-exchange resin (GQDs/PS-AER) was obtained for the detection of Fe 3+ . The linear response range of Fe 3+ was obtained from 1 μM to 7 μM and the detection limit was as low as 0.65 μM. In addition, the sensor could be regenerated by adding complexing agent EDTA and be separated by using simple filtration. [ABSTRACT FROM AUTHOR]

Two star-shaped oligofluorenes with hexakis(fluoren-2-yl)benzene as core are designed and synthesized, namely Tn0 and Tn1. Diethylamino groups are attached to the side chain of fluorene units of Tn0 and Tn1 and enable them alcohol solubility, additional hydrophobic nhexyl chains are grafted on the π-extended fluorene arms of Tn1. Power conversion efficiency (PCE) as high as 8.62% and 8.80% are achieved when utilizing Tn0 and Tn1 as cathode interlayers in inverted polymer solar cells, respectively. The work function of ITO effectively decreased by introducing interlayer, resulting in high Voc of the device, besides, the wetting properties of the interlayers can be tuned by modifying the oligofluorenes with π-extended structure, and the more hydrophobic interlayer will benefit the device performance with enhanced Jsc and FF. [ABSTRACT FROM AUTHOR]

We live in exciting times for a new generation of biomarkers being enabled by advances in the design and use of biomaterials for medical and clinical applications, from nano- to macro-materials, and protein to tissue. Key challenges arise, however, due to both scientific complexity and compatibility of the interface of biology and engineered materials. The linking of mechanisms across scales by using a materials science approach to provide structure-process-property relations characterizes the emerging field of 'materiomics,' which offers enormous promise to provide the hitherto missing tools for biomaterial development for clinical diagnostics and the next generation biomarker applications towards personal health monitoring. Put in other words, the emerging field of materiomics represents an essentially systematic approach to the investigation of biological material systems, integrating natural functions and processes with traditional materials science perspectives. Here we outline how materiomics provides a game-changing technology platform for disruptive innovation in biomaterial science to enable the design of tailored and functional biomaterials-particularly, the design and screening of DNA aptamers for targeting biomarkers related to oral diseases and oral health monitoring. Rigorous and complementary computational modeling and experimental techniques will provide an efficient means to develop new clinical technologies in silico, greatly accelerating the translation of materiomics-driven oral health diagnostics from concept to practice in the clinic. [ABSTRACT FROM AUTHOR]

We fabricated a kind of luminescent ordered multilayer transparent ultrathin films (OMTFs) based on inorganic rare earth doped layered double hydroxides (Mg–Al–Eu LDHs) nanosheets and the organic ligand 2-thenoyltrifluoroacetone (TTA) via layer-by-layer assembly method. At the same time, Polyvinyl Alcohol (PVA) aqueous solution was used as intermediate linkers. UV–visible absorption spectroscopy, X-ray diffraction, fluorescence spectroscopy and scanning electron microscopy were introduced to investigate the structure and properties of these films. Surprisingly, the uniformity and the fluorescence emission intensity of OMTFs which utilized polyvinyl Alcohol (PVA) as intermediate linkers are significantly enhanced compared with that of OMTFs without PVA. Herein, it was found that the fluorescence emission intensity of this kind of ultrathin film with PVA displays a monotonic increase as the number of deposition cycles increasing, and further the films which are highly transparent, uniform and ultrathin have potential applications in the optical display devices. [ABSTRACT FROM AUTHOR]

A novel precursor PMA–Si was synthesized by modifying 1,2,4,5-benzene-tetracarboxylic acid (PMA) with 3-aminopropyltriethoxysilane (APTES). Then the hybrids were prepared by PMA–Si coordinating to lanthanide ions (Eu 3+ and Tb 3+ ) in sol–gel process. In order to improve luminescent efficiency, 1,10-Phenanthroline (Phen) was introduced to the system as the second ligand. As-prepared compounds in sol condition were coated on quartz plates to form a layer of thin film, which was different from other similar hybrids. The properties of the hybrids were characterized by FT-IR, fluorescence spectra, TG and SEM. The results showed that the obtained materials enhanced thermal stability, mechanical resistances, waterproofness as well as machining properties. [ABSTRACT FROM AUTHOR]

The present study describes the optimization of a series of novel benzoxazole–piperidine (piperazine) derivatives combining high dopamine D 2 and serotonin 5-HT 1A , 5-HT 2A receptor affinities. Of these derivatives, the pharmacological features of compound 29 exhibited high affinities for the DA D 2 , 5-HT 1A and 5-HT 2A receptors, but low affinities for the 5-HT 2C and histamine H 1 receptors and human ether-a-go-go-related gene (hERG) channels. Furthermore, compound 29 reduced apomorphine-induced climbing and 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI)-induced head twitching without observable catalepsy, even at the highest dose tested. Thus, compound 29 is a promising candidate as a multi-target antipsychotic treatment. [ABSTRACT FROM AUTHOR]

The optical properties of Mn4+-activated phosphors are heavily affected by the host and the related data are difficult to obtain, which makes quantitative design of novel phosphors with required wavelength particularly challenging. In the era of big data, computation is emerging as a vital complement to materials development. Compared with traditional calculation routes, machine learning (ML) models provide better solutions for the problems wherein understanding the underlying physics is complicated with sparse data. In this study, we developed six ML models based on a sparse and small data set to rapidly predict the peak emission wavelength of novel phosphors and use Recursive Feature Elimination (RFE) to select the best features. Among them, the K-nearest neighbors regression (KNN.r) algorithm using non-parametric regression technology can predict the value of the target variable based on the similarity between the target value and its spatial neighbors, which can tackle sparse data sets with no obvious linear relationship well and has the best prediction accuracy. These models were then used to predict 278 potential Mn4+-activated phosphor hosts extracted from the inorganic crystal structure database (ICSD), and 19 samples were selected to validate these methods. In order to overcome the lack of physical and chemical insight of KNN, a visual data analysis was carried out based on hierarchical clustering analysis (HCA), and the rule between the peak emission wavelength and the structure of host was proposed. Guided by the results of KNN and HCA, six samples were selected for the synthesis and characterization to verify our conclusions. The measured values of all these phosphors exhibit good agreement with the predicted results, suggesting the success of our methodology. Thus, the model established and the rule proposed in this paper provide a new pathway for the rapid discovery of novel phosphors. [ABSTRACT FROM AUTHOR]

Key message: The diploid wheat recessive stem rust resistance gene SrTm4 was fine-mapped to a 754-kb region on chromosome arm 2AmL and potential candidate genes were identified. Race Ug99 of Puccinia graminis f. sp. tritici (Pgt), the causal agent of wheat stem (or black) rust is one of the most serious threats to global wheat production. The identification, mapping, and deployment of effective stem rust resistance (Sr) genes are critical to reduce this threat. In this study, we generated SrTm4 monogenic lines and found that this gene confers resistance to North American and Chinese Pgt races. Using a large mapping population (9522 gametes), we mapped SrTm4 within a 0.06 cM interval flanked by marker loci CS4211 and 130K1519, which corresponds to a 1.0-Mb region in the Chinese Spring reference genome v2.1. A physical map of the SrTm4 region was constructed with 11 overlapping BACs from the resistant Triticum monococcum PI 306540. Comparison of the 754-kb physical map with the genomic sequence of Chinese Spring and a discontinuous BAC sequence of DV92 revealed a 593-kb chromosomal inversion in PI 306540. Within the candidate region, we identified an L-type lectin-domain containing receptor kinase (LLK1), which was disrupted by the proximal inversion breakpoint, as a potential candidate gene. Two diagnostic dominant markers were developed to detect the inversion breakpoints. In a survey of T. monococcum accessions, we identified 10 domesticated T. monococcum subsp. monococcum genotypes, mainly from the Balkans, carrying the inversion and showing similar mesothetic resistant infection types against Pgt races. The high-density map and tightly linked molecular markers developed in this study are useful tools to accelerate the deployment of SrTm4-mediated resistance in wheat breeding programs. [ABSTRACT FROM AUTHOR]

• The microstructure evolution along the building direction of LDED HX block sample was studied. • It is found that the liquation cracks at grain boundaries can be propagated into solidification cracks. • The Scheil model was used to explain the reason for the formation of continuous liquid film at grain boundaries. • The theory of dendrite coalescence was used to explain why the hot cracking always occurs at HAGBs. Hastelloy X (HX) block was fabricated by laser directed energy deposition (LDED). Microstructure evolution and cracking behavior of the as-deposited LDED HX were investigated. The results showed that the microstructure of LDED HX was composed of columnar grains with interior fine columnar dendrites, and some of the second phases (Laves, M 6 C, σ, M 23 C 6) caused by micro-segregation can be observed at the inter-dendrite and grain boundary. From the bottom to the top of the sample, the grain size became coarser and the micro-segregation intensified due to the decreasing cooling rates. The formation of continuous γ-M 23 C 6 eutectic at the grain boundaries led to the hot cracking at the middle and top of the sample. Hot cracking was determined to be caused by a stable liquid film and thermal stress. The liquid film was caused by continuous γ-M 23 C 6 eutectic, and the stability of the liquid film was depended on dendrite coalescence undercooling, Δ T b , which was related to the misorientation angle θ. When the misorientation angle exceeds 11.6°, the dendrite coalescence undercooling, Δ T b > 0. The liquid film was stable at the grain boundary. Therefore, cracking always occurred at high angle grain boundaries (HAGBs). The stress concentration at the grain boundaries was intensified at the middle and top of the sample and provided the driving force for crack initiation and propagation. Carbide particles at the grain boundary promoted a pinning effect on the liquid feeding, which led to the liquation cracking propagating to solidification cracking. [ABSTRACT FROM AUTHOR]

Previous studies documented that a distinct southward shift of central Pacific low-level wind anomalies occurring during the ENSO decaying phase is caused by an interaction between the western Pacific annual cycle and El Niño-Southern Oscillation (ENSO) variability. The present study finds that the meridional movement of the central Pacific wind anomalies appears only during traditional eastern Pacific El Niño (EP El Niño) events rather than in central Pacific El Niño (CP El Niño) events in which sea surface temperature (SST) anomalies are confined to the central Pacific. The zonal structure of ENSO-related SST anomalies therefore has an important effect on meridional asymmetry in the associated atmospheric response and its modulation by the annual cycle. In contrast to EP El Niño events, the SST anomalies of CP El Niño events extend farther west toward the warm pool region with its climatological warm SSTs. In the warm pool region, relatively small SST anomalies are thus able to excite convection anomalies on both sides of the equator, even with a meridionally asymmetric SST background state. Therefore, almost meridionally symmetric precipitation and wind anomalies are observed over the central Pacific during the decaying phase of CP El Niño events. The SST anomaly pattern of La Niña events is similar to CP El Niño events with a reversed sign. Accordingly, no distinct southward displacement of the atmospheric response occurs over the central Pacific during the La Niña decaying phase. These results have important implications for ENSO climate impacts over East Asia, since the anomalous low-level anticyclone over the western North Pacific is an integral part of the annual cycle-modulated ENSO response. [ABSTRACT FROM AUTHOR]

Er 3+ -doped, Er 3+ /Yb 3+ co-doped tellurite glass with and without Ag NPs were synthesized by melt-quenching method. The high resolution transmission electron microscopy (HR-TEM) and selected area electron diffractions (SAED) manifest growth of Ag NPs. The UV–vis–NIR absorption spectroscopy and fluorescence spectroscopy were measured. The optical band gap and multiphonon relaxation rate constants were calculated. The electronic band structure and local density of state (DOS) of Ag NPs are calculated. The fluorescence emission and enhancement mechanism including localized surface plasmon resonance (LSPR) and energy transfer (ET) microcosmic mechanism were discussed. The electric field distributions of Ag NPs are emulated by FDTD solutions software. Local field enhancement (LFE) induced by LSPR and lightning rod effect was found to be responsible for the fluorescence enhancement while energy transfer from Ag NPs to rare-earth was considered ignorable in the samples without photoluminescent emission. [ABSTRACT FROM AUTHOR]

In this paper, we establish the quaternionic versions of several results in the complex pluripotential theory by using the quaternionic closed positive currents, which were introduced in [24] . We show that quasicontinuity, one of the most important properties of complex plurisubharmonic functions, holds also for quaternionic plurisubharmonic functions in H n . Moreover, we prove an equivalent characterization of the maximality, which is central to the pluripotential theory. A locally bounded plurisubharmonic function u is maximal if and only if it satisfies the homogeneous quaternionic Monge–Ampère equation ( Δ u ) n = 0 . [ABSTRACT FROM AUTHOR]

The present work identifies two types of La Niña based on the spatial distribution of sea surface temperature (SST) anomaly. In contrast to the eastern Pacific (EP) La Niña event, a new type of La Niña (central Pacific, or CP La Niña) is featured by the SST cooling center over the CP. These two types of La Niña exhibit a fundamental difference in SST anomaly evolution: the EP La Niña shows a westward propagation feature while the CP La Niña exhibits a standing feature over the CP. The two types of La Niña can give rise to a significantly different teleconnection around the globe. As a response to the EP La Niña, the North Atlantic (NA)-Western European (WE) region experiences the atmospheric anomaly resembling a negative North Atlantic Oscillation (NAO) pattern accompanied by a weakening Atlantic jet. It leads to a cooler and drier than normal winter over Western Europe. However, the CP La Niña has a roughly opposing impact on the NA-WE climate. A positive NAO-like climate anomaly is observed with a strengthening Atlantic jet, and there appears a warmer and wetter than normal winter over Western Europe. Modeling experiments indicate that the above contrasting atmospheric anomalies are mainly attributed to the different SST cooling patterns for the two types of La Niña. Mixing up their signals would lead to difficulty in seasonal prediction of regional climate. Since the La Niña-related SST anomaly is clearly observed during the developing autumn, the associated winter climate anomalies over Western Europe could be predicted a season in advance. [ABSTRACT FROM AUTHOR]

Clonal plants have been shown to successfully survive in stressful environments, including salinity stress, drought and depleted nutrients through clonal integration between original and subsequent ramets. However, relatively little is known about whether clonal integration can enhance the performance of clonal plants under alkalinity stress. We investigated the effect of clonal integration on the performance of a typical rhizomatous clonal plant, Leymus chinensis, using a factorial experimental design with four levels of alkalinity and two levels of rhizome connection treatments, connected (allowing integration) and severed (preventing integration). Clonal integration was estimated by comparing physiological and biomass features between the rhizome-connected and rhizome-severed treatments. We found that rhizome-connected treatment increased the biomass, height and leaf water potential of subsequent ramets at highly alkalinity treatments but did not affect them at low alkalinity treatments. However, rhizome-connected treatment decreased the root biomass of subsequent ramets and did not influence the photosynthetic rates of subsequent ramets. The biomass of original ramets was reduced by rhizome-connected treatment at the highest alkalinity level. These results suggest that clonal integration can increase the performance of clonal plants under alkalinity stress. Rhizome-connected plants showed dramatically increased survival of buds with negative effects on root weight, indicating that clonal integration influenced the resource allocation pattern of clonal plants. A cost-benefit analysis based on biomass measures showed that original and subsequent ramets significantly benefited from clonal integration in highly alkalinity stress, indicating that clonal integration is an important adaptive strategy by which clonal plants could survive in local alkalinity soil. [ABSTRACT FROM AUTHOR]

Ho 3+ /Yb 3+ codoped TeO 2 –WO 3 –ZnO–ZnX 2 (X = F, Cl) glasses were prepared by melt-quenching method. The absorption spectra, transmittance spectra, X-ray diffraction (XRD) curves, Raman spectra and mid-infrared fluorescence spectra were measured, along with the Judd–Ofelt intensity parameters, stimulated emission and absorption cross-sections were calculated to evaluate the effects of halide amount of the spectroscopic properties. It is shown that the introduction of an appropriate amount of halide can further improve the mid-infrared fluorescence intensity through an enhanced phonon-assisted energy transfer between Ho 3+ /Yb 3+ ions and the energy transfer mechanisms are investigated quantitatively in detail by calculating energy transfer microparameters and phonon contribution ratios. The results indicate that this kind of glasses is a promising material for mid-infrared optical fiber. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the dissolution and transformation characteristics of phyllosilicate under low molecular weight organic acids in the farmland environment (pH 4.0–8.0). Changes of dissolution and morphology of biotite were evaluated using chemical extraction experiments and in situ/ex situ atomic force microscopy (AFM) with fluids of citric acid (CA) solution at pH 4.0, 6.0, and 8.0. Results of extracting experiments show that CA solutions contributed to the release rate of potassium (K), silicon (Si), and aluminum (Al) from biotite relative to a control aqueous solution. In situ AFM observations indicate that the dissolution of biotite from the biotite (0 0 1) surface occurred on the terrace, segment, and fringe of pits, while new etch pits did not readily form on biotite (0 0 1) surfaces in aqueous solutions. However, dissolution rates of terraces can be greatly accelerated with the help of citrate. In pH 4.0 CA solution, 70 min dissolution reactions of biotite (0 0 1) surfaces result in more etch pits than in pH 6.0 and 8.0 solutions. In addition, the transformation of biotite occurred simultaneously with the dissolution process. Secondary coating was observed on the biotite (0 0 1) surface after 140 h of immersion in a weak acid environment. Thus, the protons have a dominant role in the dissolution process of biotite with organic (carboxyl) acting as a catalyst under acidic condition. Based on the theory of interactions on a water–mineral interface in a weak acid environment, dissolution of biotite starts from defect/kink sites on the surface, one layer by one layer, and develops along the [ h k 0] direction. A secondary coating that forms on the biotite (0 0 1) surface may restrain the formation and growth of etch pits, whereas this process may have a positive role on the stability of soil structure during long-term soil management. [ABSTRACT FROM AUTHOR]

Two alcohol‐soluble organic molecules are synthesized and introduced into inverted organic solar cells as the cathode interlayer. A power conversion efficiency as high as 9.22% is obtained by using the more hydrophobic molecule FTBTF‐N as the cathode interlayer. Morphological studies suggest that design of the backbone can help to enhance short‐circuit current density and fill factor. [ABSTRACT FROM AUTHOR]

A novel and simpleapproach was used to fabricate 3D porous honeycomb-like metal-free electrocatalyst. Unique 3D hierarchically macroporous structure shortens transport distances of ions through the well-interconnected intermediate structure, which provides a continuous pathway endowing for the fast electron transport. The extremely outstanding catalytic activities of the as-developed N,P-HLC were ascribed to ordered honeycomb-like macroporous structure which provides mechanical support, facilitates the circulation of electrolyte and promote the occurrence of reactions. [Display omitted] • 1. The honeycomb-like macroporous material is obtained by a simple synthesis strategy. • 2. N, P co-doped carbon displays remarkable ORR performance in acidic and alkaline media. • 3. High activity profits from the synergistic effect of ordered macroporous carbon. The fabrication of superior oxygen reduction reaction (ORR) electrocatalysts, a challenging process, is currently focuses on expensive and rare platinum (Pt) group based metals. However, these noble metals-based electrocatalysts often suffer from disadvantages, including poor stability, exorbitant price, and low selectivity. Here, we report a simple strategy to synthesize a porous honeycomb-like carbon-based electrocatalyst codoped with nitrogen (N) and phosphorus (P) without any template. Benefiting from the synergistic impact of N, P co-doping, the as-developed honeycomb-like carbon (N,P-HLC) displays splendid ORR electrochemical activity with a large onset potential of 1.0 V (vs. RHE), and half-wave potential (E 1/2) of 0.85 V (vs. RHE). What's more, N,P-HLC displays remarkable ORR performance under the super low electrocatalyst loading capacity of 0.15 mg cm−2, which is highly comparable to benchmark Pt/C (E 1/2 = 0.83 V, loading capacity 0.38 mg cm−2). Meanwhile, N,P-HLC also exhibits exceptional ORR activity in the harsh acid conditions. This work introduces a robust, low-cost and superb electrocatalytic materials to replace the noble metal-based ORR electrocatalysts. [ABSTRACT FROM AUTHOR]