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[Display omitted] Aerosol ammonium (NH 4 +), mainly produced from the reactions of ammonia (NH 3) with acids in the atmosphere, has significant impacts on air pollution, radiative forcing, and human health. Understanding the source and formation mechanism of NH 4 + can provide scientific insights into air quality improvements. However, the sources of NH 3 in urban areas are not well understood, and few studies focus on NH 3 /NH 4 + at different heights within the atmospheric boundary layer, which hinders a comprehensive understanding of aerosol NH 4 +. In this study, we perform both field observation and modeling studies (the Community Multiscale Air Quality, CMAQ) to investigate regional NH 3 emission sources and vertically resolved NH 4 + formation mechanisms during the winter in Beijing. Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH 3 emissions, including fossil fuel sources, NH 3 slip, and biomass burning, are important sources of aerosol NH 4 + with more than 60% contribution occurring on heavily polluted days. In contrast, volatilization-related NH 3 sources (livestock breeding, N-fertilizer application, and human waste) are dominant on clean days. Combustion-related NH 3 is mostly local from Beijing, and biomass burning is likely an important NH 3 source (∼15%–20%) that was previously overlooked. More effective control strategies such as the two-product (e.g., reducing both SO 2 and NH 3) control policy should be considered to improve air quality. [ABSTRACT FROM AUTHOR]

[Display omitted] • A microscopic mycelium dataset was curated, representing the first of its kind for edible fungal mycelium quality determination. • An improved model CCHA YOLO was proposed for multi-scale object detection, which has been optimized through modifications to the backbone (C3Swin), head (CBAM), and post-processing methods (NWD-NMS and NWD-loss). • Validation and ablation experiments have demonstrated that CCHA YOLO outperforms other SOTA detection models in mycelium vitality detection. • CCHA YOLO has been applied in a web-based edge deployment, facilitating practical mycelium microscopic detection. Microscopic examination is commonly employed to assess edible fungal mycelium vitality. However, this method can become time-intensive when evaluating a substantial volume of hyphae samples, which implies an urgent need to develop an accurate and automatic determination method. The challenges of mycelium detection come mostly from the multi-scale target detection under various magnifications. In this study, microscopic images of 10 edible fungi strains under different magnification scales or stain colors were collected to create a dataset. An improved multi-scale object detection model for mycelium vitality detection, CCHA YOLO, was proposed by enhancing the Backbone via combining Yolov8m and Swin Transformer (SwinT). Meanwhile, the Convolutional Block Attention Module (CBAM) was introduced to the Head, as well as optimized post-processing techniques to further promote model performance. The results indicated that CCHA YOLO achieved a mAP 50:95 (mean average precision) of 89.02 % with a computational load of 98.61 GFLOPs. Additionally, it indicates a 16.67 % accuracy enhancement, needing only 11.3 more computational operations compared to the baseline YOLOv8m. In the meantime, CCHA YOLO was deployed on the web-based edge to facilitate the detection of microscopic images, highlighting the practical applicability of CCHA YOLO in determining mycelium vitality. [ABSTRACT FROM AUTHOR]

Amino acids (AAs) are involved in the global nitrogen cycle and are important components of nitrogenous organic aerosols. Protein and free amino acid (FAA) concentrations in total suspended particulate (TSP) and their major emission sources were investigated in spring and autumn at Mount Tai (Mt. Tai) on the North China Plain and the nearby city named Liaocheng. There were significant spatial and seasonal differences in protein and FAA concentrations, with rainfall producing lower concentrations. For chiral isomers of AAs, there were significant diurnal differences in D/L-Methionine (Met), which was probably due to FAA source differences caused by regional valley winds and background winds. The high D/L-aspartic acid (Asp) and D/L-glutamine (Glu) concentrations may be indicative of the important contributions of chunk and honeycomb coal combustion. Stable nitrogen isotope analyses revealed that plant debris, soil dust, and biomass burning were important sources of glycine (Gly). Biomass burning, as well as chunk and honeycomb coal combustion, produced large amounts of L-arginine (Arg). Soil dust was the dominant source of FAAs for both Mt. Tai and Liaocheng, while biomass burning contributed more in autumn, and the proportional contribution of plant debris increased in spring. [Display omitted] • Molecular compositions and sources of atmospheric free amino acids in mountainous and urban aerosols were compared. • D/L ratio and stable nitrogen isotope analyses were used together to determine the source of particulate free amino acids. • Mechanism of regional transport of particulate free amino acids in mountainous area is proposed. [ABSTRACT FROM AUTHOR]

Amino acids (AAs) including D- and L- enantiomers are a group of organic nitrogen species in ambient aerosol. Due to the low abundances of AAs (level of ng/m3) and the matrix effects by coexistent components, it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution conditions. In this study, we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fluorescence detector (HPLC-FLD). Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution episodes. The results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon (as a proxy of organic matter) and water-soluble ion of NH 4 +. To remove the matrix effects, we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample extract. After pretreatment, 18 AAs including 6 pairs of D- and L-enantiomers (i.e., leucine, isoleucine, valine, alanine, serine, and aspartic acid) can be successfully separated and quantified in aerosol samples by HPLC-FLD. The recoveries are in the range of 67%-106%. This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers determination. We suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the influence of biomass burning. [ABSTRACT FROM AUTHOR]

We analyzed 13C characteristics in samples of bird bones, feathers, eggshell carbonate and membrane from modern specimens of red-footed booby (Sula sula) as well as fish muscle, scales, and bones from its predominant food source, flying fish (Exocoetus volitans), and muscle from its secondary food source squid (Loligo chinensis), as well as in ancient sub-fossil samples of seabird and flying fish at the Xisha Islands, South China Sea. δ13C is tissue-specific in both seabirds and flying fish due to the variance in turn-over among the tissues and differences in the type and content of amino acids across a diverse range of tissues. The δ13C discrimination factors also differed significantly among the various tissues between tropical seabirds and their prey. A Suess effect, caused by fossil fuel combustion and the emission of carbon with fewer 13C isotopes, was observed in the bird and fish tissue from ancient to modern time. Our study provides a multiple variability index for δ13C in organisms along a food chain, and verifies that tissue-specific 13C analysis is essential to identify diet and species and thus is a valuable tool for research on tropical seabird ecology. [ABSTRACT FROM AUTHOR]

Tropical seabirds play a key role in coral island ecosystems, but there are still many uncertainties regarding their paleoecology. Seabird paleoecology was investigated on Nandao Island, Xisha Islands, South China Sea, from sub-fossil remains spanning the past 800 years. Ornithogenic sediments were collected beneath seabird-inhabited shrubs where a large number of seabird/fish sub-fossils were recovered. We used reflectance spectroscopy to show that seabird population size was overall higher during the Little Ice Age (LIA) compared to periods before and after this event. Nonetheless, the number of seabirds also fluctuated during the LIA. Seabird populations on Nandao reached their highest points at 1480–1550 and 1650–1800 CE, respectively, but the population remained low from 1550 to 1650 CE. A large migration of seabirds from Nandao Island to the adjacent Beidao Island, where the population size surged at that time, is hypothesized to explain the corresponding decrease in the seabirds at Nandao. Stable isotope (δ 15 N and δ 13 C) analyses also suggest a change in foraging behavior by seabirds at Nandao during the period 1550–1650 CE. Seabirds at low population size foraged near the island and preyed upon smaller flying fish as inferred from low δ 15 N and high δ 13 C values in fish scales, but fed upon larger flying fish farther from the island during times of high population. This shift in foraging behavior is in accordance with predictions for Ashmole's Halo in that islands with high densities of birds will cause a depletion of resources near the colonies and force more distant foraging away from the colony. [ABSTRACT FROM AUTHOR]

Abstract: Compound‐specific 15N analysis of amino acids (AAs) is a powerful tool to determine the trophic position (TP) of organisms. However, it has only been used in a few studies of avian ecology because the AA patterns in the consumer‐diet nitrogen trophic discrimination factor (TDFGlu‐Phe = ∆15NGlu−∆15NPhe) were unknown in birds until recently, and tropical seabirds have never been investigated with this methodology. Here, we explore the application of this method to tropical seabirds. In this study, we recovered the fossilized bones of tropical seabirds from ornithogenic sediments on two coral islands in the Xisha Islands, South China Sea, as well as the bones and muscle of their predominant food source, flying fish (Exocoetus volitans). Compound‐specific 15N and 13C analyses of AAs in both seabird and fish bone collagen were conducted. The TP of flying fish was calculated based on a widely used single TDFGlu‐Phe approach. We then calculated the TP of tropical seabirds in three different ways: (a) according to the composition of their diet; (b) based on the single TDFGlu‐Phe approach; and (c) using a multi‐TDFGlu‐Phe approach. The results of the multi‐TDFGlu‐Phe approach were much closer to the results based on the composition of the seabird diet than the results of the single TDFGlu‐Phe approach, confirming its applicability for tropical seabirds. For seabird bone samples of different ages, TP determined from the multi‐TDFGlu‐Phe approach was most similar to that of bulk δ15N of bird collagen, with seabirds occupying higher TPs during the Little Ice Age, as previously shown. In addition, the 13C Suess effect was reflected in the AAs δ13C in our samples. This study applied a compound‐specific 15N analysis of AAs to determine the TP of tropical seabirds that has potential to extend to all tropical seabirds many of which are widely distributed and play a key role in the evolution of coral island ecosystems. [ABSTRACT FROM AUTHOR]

The nitrogen (N) utilization strategy of plants has become a topic of interest within the field of phytoecology. However, few studies have considered N cycling on coral island ecosystems from the perspective of their evolution. The aim of this study was to test the impacts of biological transport by seabirds, on the sources and uses of N by plants, and pathways of N cycling in soil–plant ecosystems on coral islands. A series of eight coral islands were investigated, five of which were affected to a varying extent by seabirds. The total phosphorus (TP) concentration from avian sources and the δ 15 N values of total nitrogen (TN) and inorganic nitrogen (IN: NH 4 + -N, and NO 3 − -N), δ 18 O of NO 3 − -O, in soils were determined, as well as proxies in plant leaves of two dominant plant species, including TN, the carbon/nitrogen ratio (C/N), and δ 13 C and δ 15 N values. The results show that, with an increase of TP, the TN and IN content, and δ 15 N values in soils all increased. Plant C/N and δ 15 N values decreased and increased, respectively, as the soil N content increased. When the TN content of the soil was low, the δ 15 N value in plant leaves was similar to that in soil NO 3 − , but was much lower than that in soil NH 4 + . When the soil TN content was high, the δ 15 N values were similar. Both plants and soil were probably N-limited prior to seabird colonization, with the N source on the barren coral islands originating primarily from atmospheric deposition. With seabird guano input and subsequent pedogenesis, the source of N switched to guano. Under these conditions, most of the N utilized by plants originated from NH 4 + , while nitrate is dominant for non-seabirds islands. Seabird activities have played a key role in the N dynamics of soil–plant ecosystems at coral islands. [ABSTRACT FROM AUTHOR]

[Display omitted] • Massive organic nitrogen excreted by penguin are input into ice-free soils in Antarctica. • Guano-affected soil organic nitrogen tends to be oxidized into relatively stable molecules. • A detailed schematic diagram of the Antarctic nitrogen cycle is proposed. Organic nitrogen (ON) is an important participant in the Earth's N cycle. Previous studies have shown that penguin feces add an abundance of nutrients including N to the soil, significantly changing the eco-environment in ice-free areas in Antarctica. To explore the molecular transformation of ON in penguin guano-affected soil, we collected guano-free weathered soil, modern guano-affected soil from penguin colonies, ancient guano-affected soil from abandoned penguin colonies, and penguin feces from the Ross Sea region, Antarctica, and Fourier transform ion cyclotron mass spectrometry (FT-ICR MS) was used to investigate the chemical composition of water-extractable ON. By comparing the molecular compositions of ON among different samples, we found that the number of ON compounds (>4,000) in weathered soil is minimal, while carboxylic-rich alicyclic-like molecules (CRAM-like) are dominant. Penguin feces adds ON into the soil with > 10,000 CHON, CHONS and CHN compounds, including CRAM-like, lipid-like, aliphatic/ peptide-like molecules and amines in the guano-affected soil. After the input of penguin feces, macromolecules continue to degrade, and other ON compounds tend to be oxidized into relatively stable CRAM-like molecules, this is an important transformation process of ON in guano-affected soils. We conclude the roles of various forms of ON in the N cycle are complex and diverse. Combined with previous studies, ON eventually turns into inorganic N and is lost from the soil. The lost N ultimately returns to the ocean and the food web, thus completing the N cycle. Our study preliminarily reveals the molecular transformation of ON in penguin guano-affected soil and is important for understanding the N cycle in Antarctica. [ABSTRACT FROM AUTHOR]

Marine sediments have been frequently used to reconstruct the records of environment change and human activities. We collected four sediment cores from Wanquan River estuary and the eastern continental shelf of Hainan Island in the South China Sea, and analyzed the down-core physical and chemical properties of sub-samples. Based on 210 Pb dating, the longest core had a record of the most recent 200 years, while the other three profiles were slightly younger. The results show that both the TOC/TN ratios and fossil fuel-corrected organic δ 13 C of marine sediments for all four cores remained relatively constant before 1950 AD, indicating relatively stable sedimentary material sources. However, after 1950 AD, the TOC/TN ratios and organic δ 13 C in all four sediment cores displayed decreasing and increasing trends, respectively, indicating that the proportion of marine-derived material increased, whereas the land-derived materials that were mainly transported by the Wanquan River decreased. This is consistent with the obvious decrease in runoff and sediment discharges of the Wanquan River due to the increase in human activities, including industrial and agricultural production, and domestic water use in Hainan Island since 1950 AD. Therefore, we suggest that environmental changes on the land were recorded by changes in the source material of marine sediments collected from coasts and estuaries. [ABSTRACT FROM AUTHOR]

Organic carbon isotopes in sediments have been frequently used to identify the source of organic matter. Here we present a study of organic δ13C on two sediment profiles influenced by guano from Guangjin and Jinqing islands in the Xisha Archipelago, South China Sea. Organic matter from ornithogenic coral sand sediments has two main sources, guano pellets and plant residues, and their organic δ13C ( δ13COM) are significantly different Organic carbon δ13Cguano is much higher than δ13Cplant, and δ13COM of bulk samples is intermediate. Based on a two-end-member mixing model, the proportions of guano- and plant-derived organic matter in the bulk samples were reconstructed quantitatively. The results showed that seabirds began to inhabit the islands around approximately 1200-1400 AD, and that guano pellets have been an important source of soil organic matter since then. With the accumulation of guano-derived nutrients, plants began to develop prosperously on the islands in the last 200 years, which is reflected by the significant increase of plant-derived organic matter in the upper sediment layer. However, guano-derived organic matter decreased greatly in recent decades, indicating a rapid decrease in seabird population. Our results show that organic δ13C can be effectively used to quantitatively determine different source contributions of OM to bulk ornithogenic coral sand sediments. [ABSTRACT FROM AUTHOR]

Quantifying variation in animals’ paleodiet from the fossil record is difficult as a continuous record of their remains is difficult to obtain. Here we assess dietary change in seabirds from Guangjin Island, Xisha Archipelago, South China Sea, by using stable nitrogen isotopes in seabird bones and prey remains collected from a coral sand ornithogenic sediment profile. δ15N of seabird bone collagen varied from 11.7‰ to 14.1‰ (averaging 12.8‰ ± 0.4‰), but that of fish bones and scales showed minor variations. Flying fish and squid are two favorite foods of tropical seabirds, and the average values of muscle δ15N in typical flying fish and squid samples were 9.2‰ and 10.2‰, respectively. Based on nitrogen isotope mass balance calculation, we conclude that flying fish accounts for 80% ± 40% of seabird diet averaged over the past 1200 years, but this prey accounted for only about 37% ± 30% during the ‘Little Ice Age’ (AD 1400–1850). Flying fish averaged up to 88% ± 2% during the ‘Medieval Warm Period’ (AD 850–1200), close to modern observed value of 89.6%. Thus, it appears that seabirds on Guangjin Island mainly preyed on flying fish during warm periods, and shift to squid during cooler periods. Our results suggest that recent global warming and human activities have likely caused a rapid decrease in tropical seabird population and dietary shift. [ABSTRACT FROM AUTHOR]

The assembly of proteins into various nano-objects with regular and periodic microstructures, i.e. protein arrays, is a fast-growing field in materials science. Due to the structural complexity of proteins, reports in this field are still quite limited. In this review, we summarize the recent developments in protein array construction by different driving forces, including electrostatic interactions, metal–ligand interactions, molecular recognition and protein–protein interactions. In line with our particular interest, assemblies driven by molecular recognition are particularly explored. Finally, functionalities of the obtained protein arrays are briefly discussed. [ABSTRACT FROM AUTHOR]

Sulfamethoxazole (SMX) is highly persistent and difficult to remove, making it urgent to find an efficient method for alleviating the enormous environmental pressure of SMX. In this study, sulfide-modified nanoscale zero-valent iron on carbon nanotubes (S-nZVI@CNTs) was prepared to activate peroxydisulfate (PDS) for the degradation of SMX. The results showed that SMX was completely removed within 40 min (k obs =0.1058 min−1) in the S-nZVI@CNTs/PDS system. By analyzing quenching experiments and electron paramagnetic resonance (EPR), singlet oxygen (1O 2) was the main active species of the S-nZVI@CNTs/PDS system. 1O 2 might be mediated by the abundant carbonyl groups (C O) on carbon nanotubes through spectroscopic analyses. In addition, sulfur doping transitioned the activation pathway to a nonradical pathway. Spectroscopic analyses and electrochemical experiments confirmed that the formation of CNTs-PDS complexes and S-nZVI could promote electron transfer on the catalyst surface. Furthermore, the main degradation intermediates of SMX were identified, and five possible transformation pathways were proposed. The S-nZVI@CNTs/PDS system possessed advantages including high anti-interference (Cl-, NO3-, HA), a strong applicability, recyclability and a low PDS consumption, offering new insight into the degradation of antibiotic wastewater. [Display omitted] • S-nZVI@CNTs exhibited excellent performance for PDS activation to degrade SMX. • Carbonyl groups played a key role in the generation of singlet oxygen. • S-nZVI@CNTs combined with PDS to produce electron complexes. • Sulfide-modified nanoscale zero-valent iron accelerated electron transfer. [ABSTRACT FROM AUTHOR]

Highlights: [•] RE addition in the alloys causes the formation of Al2RE/Al3RE. [•] RE addition can improve the RT tensile properties of the alloys. [•] The mechanical properties of the alloys after homogenization become worse. [Copyright &y& Elsevier]

In current work, we have used fiber laser welding (FLW) technology to manufacturing the Ti–6Al–4V (TC4) and Inconel 718 (IN718) bimetallic structure and to prevent the formation of brittle phases via Cu/Ta multi-interlayer. The results of this study showed that Cu/Ta multi-interlayer was very effective in preventing the formation of continuous brittle intermetallic layers of Ti–Ni and Ti–Cu. The good metallurgical bonds were presented at these interfaces between TC4 and IN718. As a result, the joints with gradational structure, i.e. TC4| (α+β Ti, Ta) ss | (β Ti, Ta) ss | Ta(s, s)+ (Cu(s, s)+ Ta(s, s)+ Ti 3 Ni 4)| Cu(s, s)+ (Cu(s, s)+ Ta(s, s))| Ni(Ta, Fe, Cr) ss | IN718 can be formed, which can contribute high tensile strength of joints with the value of 396 MPa. •In this paper, we use a new Cu/Ta multi-interlayer layer for fiber laser welding TC4 and IN 718. •The formation of continuous brittle intermetallic layers of Ti–Ni and Ti–Cu is effectively prevented. The tensile strength of the bimetallic structure with the Cu/Ta multi-interlayer was 396 MPa, which reached that of the 42.6% and 45.8% of the tensile strength of TC4and IN718, respectively. •In the present work, defect-free, dissimilar FLW of the bimetallic structure was successfully achieved by using Cu/Ta multi-interlayer. The typical microstructure of joint is TC4| (α+β Ti, Ta)ss| (β Ti, Ta)ss| Ta(s, s)+ (Cu(s, s)+ Ta(s, s)+ Ti3Ni4)| Cu(s, s)+ (Cu(s, s)+ Ta(s, s))| Ni(Ta, Fe, Cr)ss| IN718. [ABSTRACT FROM AUTHOR]

Abstract: The influence of Y on microstructure and mechanical properties of as-cast Mg–5Li–3Al–2Zn alloy was investigated. The results show that the phase compositions of Mg–5Li–3Al–2Zn consist of α-Mg and AlLi phases. Adding Y to the alloy results in the formation of Al2Y compound and facilitates grain refinement. The addition of 0.8wt.% Y produces the smallest grain size. The tensile tests performed at room temperature show that the additions of Y can improve the mechanical properties of the alloy; the tensile strength and ductility reach peak values when the Y additions are 0.8wt.% and 1.2wt.%, respectively. The mechanisms of improvement are related to grain refinement and compound strengthening effects. [Copyright &y& Elsevier]

Abstract: The aim of this study is to investigate the influence of extractives on the yield and composition of oil obtained from biomass samples (Artemisia ordosica, corn stalk and wheat straw). Direct deoxy-liquefaction experiments of original and extracted biomass were performed at certain temperature in a stainless steel tubular reactor. Benzene–alcohol solvent extraction had significant effect on the product distribution of biomass, especially on the yield and composition of the product oils. The oil yield of original biomass and alkane content in the oil were in the range of 5.44–9.27% and 8.23–23.64%, while decreased to 3.83–4.45% and 1.07–6.03% for the extracted biomass. This study concludes that most of alkanes in the oil mainly derive from the decomposition of triglyceride and hydrocarbon existed in the extractives of biomass. The results might be helpful to study the origin of alkanes and benzene derivatives in the oil obtained from biomass via direct deoxy-liquefaction. [Copyright &y& Elsevier]

Abstract: Carbon-based, non-precious-metal catalysts for the oxygen reduction reaction were prepared from aromatic polyamides, poly(meta-phenylene isophthalamide) (MPIA) mixed with FeCl2 by pyrolysis. The catalytic activity for electrochemical oxygen reduction was evaluated by the onset potential, measured at a current density of −2μAcm−2. A catalyst prepared by multistep pyrolysis had high N content and high oxygen reduction activity, with an onset potential of 0.93V. A membrane electrode assembly prepared using this catalyst showed an open circuit voltage of 0.99V and a maximum output of 0.48Wcm−2. [Copyright &y& Elsevier]

Abstract: As-cast Mg–5Li–3Al–2Zn–xRE (x =0–2.5wt.%) alloys were prepared under the ambient of pure argon, and the effects of Ce-rich rare earths (RE) and heat treatment on the microstructure and mechanical properties of Mg–Li–Al–Zn-based alloy were investigated. The results show that the main phase compositions of Mg–5Li–3Al–2Zn (LAZ532) alloy consist of α-Mg and AlLi. With the addition of RE, Al-RE precipitate forms, and increases gradually, whereas AlLi phase decreases. The room temperature tensile test reveals that the addition of RE could clearly improves the mechanical properties of alloys which are further improved after heat treatment. In more detail, excellent tensile strength and ductility are obtained in 1.5wt.% RE containing alloy in as-cast state. After heat treatment, the 1.0wt.% RE containing alloy attains superior tensile strength. The differences in tensile strength are related to the morphology, distribution of second phases and solid–solution strengthening in different alloy systems. In addition, the fracture pattern of the alloy is predominantly brittle cleavage and tends to be quasi-cleavage with RE addition. [Copyright &y& Elsevier]

Poplar leaves, poplar bark and poplar wood were deoxy-liquefied directly in an air-proof stainless steel reactor at different temperatures. The oils from leaves at 350°C, from bark at 400°C and from wood at 450°C, at which the liquid product yields were the maximum, were analyzed by GC–MS. The oils obtained from three parts of poplar tree were quite different from each other in the relative contents of their compositions. The oil from leaves was rich in hydrocarbons (alkanes: C7–C29; aromatics) and poor in phenolics, while oil from wood was rich in phenolics and poor in hydrocarbons. The oil from bark was moderate. Relative contents of hydrocarbons in the leaves oil were as high as 60.01% but decreased to 29.71% in bark oil and 11.43% in wood oil. GC analysis of gases and FT-IR, GC–MS and elemental analysis of oils were performed in this study. [Copyright &y& Elsevier]

Abstract: The relationships between morphology and proton conduction for Nafion membranes and hydrocarbon-type proton exchange membranes, namely, sulfonated poly(arylene ether ether ketone) (S-PEEK) and sulfonated poly(arylene ether sulfone) (S-PES), were investigated by small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). The direct simultaneous observation of surface morphology and active regions of proton conduction on membranes by combined high-resolution AFM phase imaging and an electrochemical technique at controlled humidity provided significant morphological information, particularly for the hydrocarbon-type membranes that exhibit few or no features on SAXS profiles. For the Nafion membranes, the active proton paths became denser and congregated with each other at over 60% RH, resulting in the formation of well-connected networks. For the hydrocarbon-type membranes, however, only the relatively small and dispersed proton paths were observed, which showed no significant change even as water content increased. We have demonstrated that the differences in microscopic morphology between the Nafion and hydrocarbon-type membranes are associated with the differences between their macroscopic proton conductivities. [Copyright &y& Elsevier]

Abstract: Bio-petroleum with unusual H/C molar ratio of 1.90 and higher heating value of 44.22MJ/kg was obtained from soybean stalk by deoxy-liquefaction (deoxygenation in the process of liquefaction). This bio-petroleum had similar composition to fossil petroleum which contains long-chain alkanes and aromatic hydrocarbons. The oil with H/C molar ratio of 2.00 and the higher heating value of 46.95MJ/kg was obtained after bathing with 1% NaOH solution by refluxing. And then this bathed bio-petroleum was directly distilled and the fractions were boiled under <120°C, 120–180°C, 180–240°C, 240–350°C, respectively, of which the distillate of 240–350°C was almost the same with diesel oil in composition and could be used as a substitute transport fuel after decolorization using activated clay. [Copyright &y& Elsevier]

The reaction of [NiCl 2 (PPh 3 ) 2 ] with in i PrOH under solvothermal conditions gives a nickeladodecaborane cluster: H 2 [Cl 2 NiB 11 H 6 -2,3,4,5,6-(O i Pr) 5 ] which was characterized by FT-IR, NMR spectroscopy and elemental analysis. It was also characterized by an X-ray diffraction study of a single crystal. The title cluster belongs to monoclinic, space group P 2(1)/ n , with crystal cell parameters: a &ThickSpace;=&ThickSpace;12.355(13)&ThickSpace;Å, b &ThickSpace;=&ThickSpace;18.471(19)&ThickSpace;Å, c &ThickSpace;=&ThickSpace;12.956(14)&ThickSpace;Å, β&ThickSpace;=&ThickSpace;93.524(18)°, Z &ThickSpace;=&ThickSpace;4, D Calcd &ThickSpace;=&ThickSpace;1.242&ThickSpace;Mg&ThickSpace;m -3 , F (000)&ThickSpace;=&ThickSpace;1160, R 1 &ThickSpace;=&ThickSpace;0.0746, wR 2 &ThickSpace;=&ThickSpace;0.1829. The cluster has a closo 12-vertex {NiB 11 } icosahedral skeleton, in which Ni connects with two Cl atoms and five B atoms. O i Pr groups substituted all five H atoms on the boron cage atoms adjacent to Ni. [ABSTRACT FROM AUTHOR]

Pt-free cathode catalysts for polymer electrolyte membrane fuel cells have been prepared by multi-step pyrolysis of FePc and PhRs, in the best of which show extensively high initial cell performance and good durability compared to other present precious-metal-free cathode catalysts to date. [ABSTRACT FROM AUTHOR]

Pt-free cathode catalysts for polymer electrolyte membrane fuel cells have been prepared by multi-step pyrolysis of FePc and PhRs, in the best of which show extensively high initial cell performance and good durability compared to other present precious-metal-free cathode catalysts to date. [ABSTRACT FROM AUTHOR]

Pt-free cathode catalysts for polymer electrolyte membrane fuel cells have been prepared by multi-step pyrolysis of FePc and PhRs, in the best of which show extensively high initial cell performance and good durability compared to other present precious-metal-free cathode catalysts to date. [ABSTRACT FROM AUTHOR]

Pt-free cathode catalysts for polymer electrolyte membrane fuel cells have been prepared by multi-step pyrolysis of FePc and PhRs, in the best of which show extensively high initial cell performance and good durability compared to other present precious-metal-free cathode catalysts to date. [ABSTRACT FROM AUTHOR]

Objective: To investigate 38 Y-chromosome short tandem repeat (Y-STR) genetic polymorphisms in Beijing Han and analyze the genetic distance with neighboring or linguistically similar populations. Materials and Methods: In the study, we selected 531 unrelated male individuals of Beijing Han, and the results were statistically analyzed by testing with GSTAR™ 41Y reagents. Results: The allele peak heights were balanced among the Y loci, the amplified fragment ranged from 100 to 500 bps. A total of 531 haplotypes were detected in 531 samples. Eight null genotypes were observed on locus DYS448. One and three double alleles were observed on single-copy locus DYS576 and DYS19, respectively. DYS385 a/b, DYF387S1 a/b, and DYS527 a/b were more common in double copies, but 3, 13, and 11 triple alleles were detected, respectively. The gene diversity values of Y-STRs except DYS391, DYS438, and DYS645 were >0.5. Twenty-seven Y-STRs of Beijing Han population were selected for genetic distance comparison with 17 populations including Changchun Han, with Rst values ranging from 0.0002 to 0.1703. Conclusion: The 38 Y-STRs in this study have strong male lineage identification ability and have great potential for individual identification, kinship identification, Y-STR database construction, and genetic relationship research. [ABSTRACT FROM AUTHOR]

Review: 74 refs. [ABSTRACT FROM AUTHOR]

• Adsorption capacities of Fe/S-BC are improved after Fe/S co-doping. • Fe/S-BC has a high adsorption capacity for As(III) and Pb(II). • The presence of Pb(II) decreased the adsorption capacity of As(III). • The synergistic effects on Pb adsorption were observed in combined pollutants. Simultaneous elimination of As(III) and Pb(II) from wastewater is still a great challenge. In this work, an iron-sulfur codoped biochar (Fe/S-BC) was successfully fabricated in a simplified way and was applied to the remediate the co-pollution of As(III) and Pb(II). The positive enthalpy indicated that the adsorption in As-Pb co-pollution was an endothermic reaction. The mechanism of As(III) removal could be illustrated by surface complexation, oxidation and precipitation. In addition to precipitation and complexation, the elimination mechanism of Pb(II) also contained ion exchange and electrostatic interactions. Competitive and synergistic effects existed simultaneously in the co-contamination system. The suppression of As(III) was ascribed to competitive complexation of the two metals on Fe/S-BC, while the synergy of Pb(II) was attributed to the formation of the PbFe 2 (AsO 4) 2 (OH) 2. Batch experiments revealed that Fe/S-BC had outstanding ability to remove As(III) and Pb(II), regardless of pH dependency and interference by various coexisting ions. The maximum adsorption capacities of the Fe/S-BC for As(III) and Pb(II) were 91.2 mg/g and 631.7 mg/g, respectively. Fe/S-BC could be treated as a novel candidate for the elimination of As(III)-Pb(II) combined pollution. [Display omitted] [ABSTRACT FROM AUTHOR]

Lamellar tin deposits were prepared by galvanostatical electroplating from the aqueous acidic-sulfate bath, with gelatin and benzalacetone dissolved in ethanol (A) as additive, and their morphologies were investigated by scanning electron microscopy. Cathodic polarization curves revealed that the absorbability of A on the cathode surface was higher than that of gelatin. X-ray diffraction analysis indicated preferred orientations of tin growth led to the formation of lamellar structure and distortion of tin lattice. The growth mechanism of lamellar tin was also discussed. [ABSTRACT FROM AUTHOR]

Although ether‐based electrolytes have gradually been identified as a vital factor to achieving the excellent electrochemical performance observed in transition metal sulfide (TMS) anodes in sodium‐ion batteries (SIBs), there is still a lack of a fundamental understanding about the origin of the positive effect of ether‐based electrolytes on TMS anodes. Herein, a microspherical CoS2 anode has been taken as a representative of TMS. It has been demonstrated that the sodiation process involves not only a traditional conversion reaction taking place between solid‐state CoS2 and Na2S, but also a solid–liquid phase conversion process between active materials and soluble sodium polysulfide (Na2Sn, 2 < n < 8). More importantly, it is first revealed that the long‐term stability and the reversibility of CoS2 anode are mainly due to the solid–liquid conversion behavior, which makes bulk CoS2 gradually develop into a stable porous structure with fast Na+ transport kinetics and small stress/strain during cycling. Consequently, the CoS2 electrode delivers remarkable long‐cycle life with an ultrahigh capacity retention rate of 94.8% even after 1500 cycles at 2 A g−1 (only 2.13 mAh g−1 fading per 100 cycles) and high volumetric capacity of 949 mAh cm−3 at a high active material loading of 3.3 mg cm−2. [ABSTRACT FROM AUTHOR]

Abstract: Co-deoxy-liquefaction of biomass and vegetable oil was investigated under the conditions of different temperatures (350–500°C) and residence time as well as catalyst using HZSM-5. Results suggested low temperature was favorable for the formation of diesel-like products, while high temperature caused more gasoline-like products. By the addition of HZSM-5, at 450°C alkanes content of the obtained oil with low oxygen content of 2.28%, reached a maximum of 56.27%, resulting in the highest HHV of 43.8MJkg−1. High temperature favored cracking activity of HZSM-5 which reduced the char formation and contributed to the removal of carbonyl. Compared to temperature, the effect of residence time on products was relatively less; experiments indicated the optimum residence time was 15min at which obtained oil with the highest yield of 17.78%, had better properties. Preliminary analysis of mechanisms showed biomass provided hydrogen for vegetable oil, facilitating hydrogenation of Cf vegetable oil. [ABSTRACT FROM AUTHOR]

The reaction of [RuCl2(PPh3)3] and closo-[B10H10]2- with p-IPhCOOH in CH2Cl2 solution affords two para-iodobenzoate exo-cyclized 11-vertex closo-ruthenaborane clusters [(PPh3)(p-IPhCO2)2RuB10H8] (1) and [(PPh3)2ClRu(PPh3)(p-IPhCO2)RuB10H9] ··· CH2Cl2 (2) that have been characterized by elemental analysis, FT-IR, 1H and 13C NMR spectra and single-crystal X-ray diffraction analysis. Both clusters are based on a closo-type C2v 1 : 2 : 4 : 2 : 2 RuB10 stack with the metal occupying the unique six-connected apical position. In 1, the metal center has three exo-polyhedral ligands: one triphenylphosphine and two native oxygen atoms of para-iodobenzoates. The other oxygen atoms of two para-iodobenzoates are additionally bonded to B(2) and B(3) atoms respectively, resulting in two exo-cyclic five-membered Ru-O-C-O-B rings and engendering a symmetrical conformation. For 2, the metal center also has three exo-polyhedral ligands, one triphenylphosphine and one para-iodobenzoate to form one exo-cyclic five-membered Ru-O-C-O-B ring. There is an additional exo-polyhedral ruthenium atom bonding to the {RuB10} center via a {Ru-Ru} linkage and two {RuHμB} bridges resulting in one closo distorted exo-polyhedral Ru(1)-Ru(2)-B(2)-B(4) tetrahedron. [ABSTRACT FROM AUTHOR]

Black carbon (BC) plays a vital role in atmospheric environment and climate change. Temporal variations and transport pathways of BC in Xiamen, China with the impacts of synoptic circulation were investigated in 2014 with Aethalometer. Annual mean BC concentration was 4270 ng m−3. BC exhibited clear diurnal (seasonal) variations, with the maximum of 6182 (4755) ng m−3 at 6:00 (in spring) and minimum of 2847 (3774) ng m−3 at 13:00 (in summer). Conditional probability function analysis indicated that high BC concentrations were associated with northwesterly winds with low wind speed. Air masses originating from the East China Sea and passing along with East China Coast had the highest BC concentrations. Potential source contribution function and concentration weighted trajectory analysis suggested that major sources for BC included the surrounding region, southwestern Fujian and eastern Guangdong to the southwest, Hubei, Hunan and Jiangxi to the northwest, the East China Sea and the South China Sea. Of the nine synoptic circulation patterns, three cyclone-related patterns were associated with low BC concentrations and small biomass burning (BC bb) contributions. Of the six anticyclone-related patterns, the three cold-high circulations around winter were associated with moderate BC concentrations and large BC bb contributions. The two cold-high patterns in spring and autumn were associated with high BC concentrations and small BC bb contributions, while the warm-high pattern was associated with moderate BC concentration and small BC bb contribution. The findings provide insights into the transport mechanisms of BC with the impacts of synoptic pattern in China. • One year on-line observation of BC was conducted in Western Taiwan Strait in China. • Originations and transport pathways of BC were investigated with CPF, PSCF and CWT. • Impacts of synoptic circulations on BC from different source sectors were analyzed. [ABSTRACT FROM AUTHOR]

The planting of salt-tolerant plants is regarded as the one of important measurements to improve the saline–alkali lands. The outstanding biological properties of JUNCAOs have made them candidates to improve and utilize saline–alkali lands. At present, little attention has been paid to developing a non-destructive and high throughput approach to evaluate the salt tolerance of JUNCAO. To close the gaps, three typical JUNCAOs (A.donax. No.1, A.donax. No.5 and A.donax. No.10) were evaluated by combining prompt chlorophyll a fluorescence (ChlF) with hyperspectral spectroscopy (HS). The results showed that salt stress reduced relative stem growth, water content, and total chlorophyll content but enhanced the malondialdehyde (MDA) content. It caused a significant change in chlorophyll a fluorescence kinetics with an appearance of L-, K- and J-band, implying damaging energetic connectivity between PSII units, uncoupling of the oxygen evolving complex (OEC) and inhibition of the Q A −reoxidation. The negative impact of salt stress on JUNCAOs increased with the increasing level of salt concentration. Effect on spectral reflectance in the in the visible region with shifts on red edge position (REP) and blue edge position (BEP) to shorter wavelength was also found in salt stress plants. Combining principal component analysis (PCA) with the membership function method based on spectral indices and JIP-test parameters could well screen JUNCAOs salt tolerant ability with the highest for A.donax. NO.10 but lowest for A.donax. NO.1, which was the same as that of using conventional approach. The results demonstrate that prompt ChlF coupling with HS could provide potentials for non-invasively and high-throughput phenotyping salt tolerance in JUNCAOs. • Salt damaged energetic connectivity, oxygen evolving complex and Q A − reoxidation. • Salt induced shifts on red and blue edge positions to shorter wavelength. • Prompt ChlF and HS have potentials for high-throughput phenotyping salt tolerance. [ABSTRACT FROM AUTHOR]

Ornithogenic sediments are rich in toxic As (arsenic) compounds, posing a potential threat to local ecosystems. Here we analyzed the distribution of As speciation in three ornithogenic sediment profiles (MB6, BI and CC) collected from the Ross Sea region, East Antarctica. The distributions of total As and total P (phosphorus) concentrations were highly consistent in all three profiles, indicating that guano input is a major factor controlling total As distribution in the ornithogenic sediments. The As found in MB6 and CC is principally As(V) (arsenate), in BI As(III) (arsenite) predominates, but the As in fresh guano is largely composed of DMA (dimethylarsinate). The significant difference of As species between fresh guano and ornithogenic sediment samples may be related to diagenetic processes after deposition by seabirds. Based on analysis of the sedimentary environment in the studied sediments, we found that the redox conditions have an obvious influence on the As speciation distribution. Moreover, the distributions of As(III) and chlorophyll a in the MB6 and BI profiles are highly consistent, demonstrating that aquatic algae abundance may also influence the distribution patterns of As speciation in the ornithogenic sediments. [ABSTRACT FROM AUTHOR]

A series of metal catalysts with mesoporous zeolites as the supporters including Cu/, Co/, Fe/, Pt/SBA-15, Cu/SBA-16, and Cu/KIT-6 was prepared via impregnation method, and further characterized by N 2 adsorption/desorption, XRD, XRF, TEM, XPS, and H 2 -TPR. The metallic cations were verified to be the main species over Cu/, Co/, Fe/SBA-15. CuO was largely formed over Cu/KIT-6 and Cu/SBA-16, while metallic Pt particles constituted the major species on Pt/SBA-15. The selective catalytic combustion (SCC) of acrylonitrile (C 2 H 3 CN) revealed that Cu/SBA-15 exhibiting a nearly complete C 2 H 3 CN conversion associated with N 2 selectivity around 64% at T > 400 °C was the most promising catalyst. In comparison with the other mesoporous copper catalysts (Cu/KIT-6, Cu/SBA-16), the higher SCC activity of Cu/SBA-15 was attributed to its larger pore aperture greatly facilitating the copper dispersion. SCC mechanism for Cu/SBA-15 sample was further investigated by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), revealing an oxidation mechanism. [ABSTRACT FROM AUTHOR]

• Rainwater DOM along the yangtze river were characterized by optical properties and FT-ICR MS. • Natural and anthropogenic emissions and climatic conditions shaped the chemodiversity of rainwater DOM. • Biogenic secondary organic compounds widely contributed to rainwater DOM along the Yangtze River Basin. Rainwater dissolved organic matter (DOM) plays an important role in the biogeochemical cycle and evolution of organic matter in the land-atmosphere interface. To better understand their sources and molecular composition in the atmosphere, rainwater samples were collected at six different locations along the Yangtze River Basin. Based on the application of a combined approach including excitation-emission matrix (EEM) fluorescence and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), various sources (terrestrial, anthropogenic, and autochthonous sources) of rainwater DOM were revealed. Results show that the derivatives of biogenic volatile organic compounds were widely distributed and contributed to rainwater DOM along the Yangtze River Basin. In the up-river city Batang, rainwater DOM was affected by the long-range atmospheric transport due to the Indian summer monsoon. Lijiang, a city on the southeastern edge of Tibetan plateau, was related to strong local biomass burning. The industrial cities of Panzhihua and Luzhou showed large differences in organic composition due to distinct industrial types. Fuling, a district in Chongqing Municipality, was significantly contributed by aged organics from biomass burning. While rainwater DOM in Shanghai, a coastal megacity, contained a high fraction of sea spray organics. Further, more than 70% of rainwater DOM molecules are associated with 36 typical transformation mechanisms during rainwater-scavenging processes, e.g., oxidation reactions, dealkylation and decarboxylation. Our study demonstrates that local natural and anthropogenic emissions and climatic conditions strongly shaped the chemodiversity and possible precursor-product pairs of rainwater DOM along the Yangtze River Basin, which helps to better understand the biogeochemical cycles of organic matter in a large-scale watershed under the influence of human activities. [Display omitted] [ABSTRACT FROM AUTHOR]

• Nitrogen-doped biochar was prepared and showed great performance for TC degradation. • The formation of a graphitized structure enhanced the catalytic performance of biochar materials. • Nitrogen doping and high pyrolysis temperature promoted the formation of the graphitized structure of biochar. • The degradation of TC mainly depended on the electron transfer process between PS and pollutants. Tetracycline (TC) is a kind of refractory pollutant and widely exists in environment, and it is urgent to develop effective methods for TC treatment. In this study, nitrogen-doped biochar (N-BCX) was successfully synthesized and was used to activate persulfate (PS) to degrade TC. The materials were characterized by XPS, Raman spectrum, SEM, BET and FT-IR. SEM and BET results showed that the catalyst had an obvious pore structure and large specific surface area, which increased with increasing pyrolysis temperature. Nitrogen doping could increase the content of graphite-N in biochar; the defect edge of the material increased, further formed the graphitization structure, and enhanced the catalytic performance of the material. TC (20 mg/L) could be completely removed within 120 min under the optimal conditions of 200 mg/L of catalyst dosage, 2 mM of PS dosage and initial pH of 7. The results of EPR, quenching experiments and electrochemical experiments showed that the degradation of TC in the system did not depend on the action of radicals, the electron transfer between TC and PS on the surface of biochar maybe the main pathway. Efficient and environmentally friendly nitrogen-doped biochar can provide a reference for the related antibiotic wastewater treatment. [ABSTRACT FROM AUTHOR]

Abstract: Since the post-casting treatments influence the water entrapped in polymeric matrix and consequently its proton conductivity, an evaluation of annealing at 200°C and acid treatments was conducted on previously developed composite s-PEEK (1.55mequiv.g−1) membranes, containing a commercial aminopropyl-functionalised silica. DSC, WAXS, SEM–EDX and laser microscope measurements carried out on membranes swollen at different temperatures highlighted different membrane properties depending on post-casting treatments. It was found that composite membranes have different structural and morphological characteristics than pristine polymer membranes. The silica distribution was modified when different treatments are used. The state of water changed when silica was inserted into the membranes. Actually, contrary to the pristine membranes the presence of freezable water was revealed at temperature lower than 80°C. The proton conductivity was also affected by the presence and the amount of water trapped into the membranes and was particularly influenced by the post-casting treatments. The silica introduction reduced the swelling effect and improved the robustness of the membranes even if a higher water content in the freezable state was observed. Acid treatment leads to significant improvement in membrane properties, but the present work shows that annealing before acid treatment can affect the membrane morphology more strongly than other treatments resulting in a much better fuel cell performance. [Copyright &y& Elsevier]

Abstract: Pyrolysis of a mixture of Fe phthalocyanine and phenolic resin (FePc/PhRs) was studied to clarify the details of the preparation protocol of nitrogen-doped carbon-based materials for cathode catalysts in polymer electrolyte membrane fuel cells. TEM images show that nanoshell carbon is formed by the pyrolysis of FePc/PhRs in the temperature range of 600–800°C. The optimum pyrolysis temperature for the FePc/PhRs mixture was 600°C, where moderate conductivity and high nitrogen content of the prepared carbon were both satisfied. This catalyst showed a promising fuel cell performance with 1.01V open-circuit voltage and 0.33Wcm−2 maximum output, at 0.2MPa absolute pressure and 80°C. A detailed study of the carbonization process suggests that the presence of Fe species during carbonization process contributes to higher nitrogen content and growth of nanoshell structure of the resulting carbon. [Copyright &y& Elsevier]

Abstract: Superlight alloys, including Mg–8Li–1Al, Mg–8Li–1Zn and Mg–8Li–1Al–1Zn, were prepared using vacuum induction melting furnace. Microstructures and phases of the alloys were studied with optical microscope and X-ray diffraction. Mechanical properties of these alloys were measured with tensile tester. The results of tensile tests show that, the as-rolled Mg–8Li–1Al alloy with a thickness of 0.16mm has the highest tensile strength (313.9MPa). The as-extruded Mg–8Li–1Zn alloy with a thickness of 3mm has the maximum elongation (44%). The as-rolled Mg–8Li–1Al–1Zn alloy with a thickness of 0.18mm has both high tensile strength and high elongation (233.38MPa and 9.2%, respectively). [Copyright &y& Elsevier]