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Heavy metals that are adhered to the surfaces of microplastics in the natural marine environment pose potential threats to marine life. However, little is known about their adsorption mechanisms and composite risks. This study collected seawater, suspended particulate matter (SPM), plankton, and microplastic samples from the waters surrounding Hong Kong, established a method for analyzing 13 heavy metals in the plastisphere, and explored the extrinsic and intrinsic sources of the heavy metals by analyzing natural matrices (seawater, SPM, and plankton) and anthropogenic plastics. We found that heavy metals in the plastisphere were significantly affected by the surrounding matrices, as indicated by its positive correlations with the heavy metals in SPM and plankton at most of the sampling sites. Heavy metals in plankton usually occurred as traces of oxides such as As2O3 and ZnO. The partition coefficients of the studied heavy metals between seawater and the plastisphere were identical to those between the SPM and the plastisphere. No correlations were found between the concentrations of heavy metals in the plastisphere and the heavy metal concentrations, masses, quantities, or surface areas of the microplastics, although some polymer types contained extremely high Cd (676 mg/kg), Pb (1,742 mg/kg), and Zn (1,712 mg/kg) concentrations. Only the Cr, Cu, and Ni concentrations were positively correlated with the specific surface area of the microplastics. A cluster analysis showed that Cr, Cu, and Ni were derived from anthropogenic sources, indicating that adventive heavy metals could be adsorbed by plastics with large specific surface areas. We also established a new composite risk assessment method for heavy metals and microplastics that leverages the specific surface areas of microplastics. The assessment results showed that Cd from Tolo Harbor had a strong ecological risk, while As and Cd from the eastern waters off Hong Kong had moderate composite ecological risks.

We study the evolution of compact convex curves in two-dimensional space forms. The normal speed is given by the difference of the weighted inverse curvature with the support function, and in the case where the ambient space is the Euclidean plane, is equivalent to the standard inverse curvature flow. We prove that solutions exist for all time and converge exponentially fast in the smooth topology to a standard round geodesic circle. This has a number of consequences: first, to prove the isoperimetricinequality; second, to establish a range of weighted geometric inequalities; and third, to give a counterexample to the $n=2$ case of a conjecture of Gir\~ao-Pinheiro., Comment: 17 pages

Purpose This paper aims to study the sensitivity enhancement effect of the gold nanorod on fiber surface plasmon resonance (SPR) sensor. It proposes modeling the sensing effects of fiber SPR sensor decorated with metal nanoparticles. By using simulation and experiment, the sensitivity enhancement effect of the gold nanorod was studied and demonstrated. Design/methodology/approach The paper opted for an exploratory study using simulation approach of finite-difference time-domain. Specifically, the effect of ratios and aspect ratios of gold nanorod on sensing performance are investigated theoretically. Based on the mathematical models, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 were done to verify the sensitivity enhancement effect of the gold nanorod. Findings In conclusion, it is evident that with the increases of the aspect ratios, the sensing sensitivity of the refractive index increases first, then gradually stabilizes or decreases. After parameter optimization, the ratios and aspect ratios of gold nanorod are chosen to be 8 nm and 12.5, respectively, which makes the optimal refractive index sensitivity of 4465.53 nm/RIU be realized. In addition, the validation experiments by using the gold nanorod with the aspect ratios of 5.1 verify the sensitivity enhancement effect of the gold nanorods. Originality/value This paper proposes and demonstrates a new method for the sensitivity enhancement of fiber SPR sensor. After parameter optimization, the maximum sensitivity of 4465.53 nm/RIU was achieved by using 8 nm gold nanorods with the aspect ratios of 12.5. To verify the sensitivity enhancement of the gold nanorods, the authors also did the validation experiments. The testing results indicated that after the decoration of the gold nanorods, the sensitivity of the sensing probe increases from 2190.57 nm/RIU to 2693.24 nm/RIU, which demonstrates the sensitivity enhancement effect of the gold nanorods.

The detection of a water-rich plume erupting from ‘tiger stripes’ near the Enceladus south polar region is an important discovery of geologically active satellites within the Solar system. In this work, we apply an analytical approach to model the plume structure, using as a diagnostic the CO2 distribution extracted from the Cassini Ion and Neutral Mass Spectrometer measurements made during the E14, E17, and E18 flybys. Special focus is placed on the modelling of the spike-like structures by including only sources with substantial contributions to the plume densities. Such a procedure reduces greatly the model complexity and helps to better constrain the source parameters. Both the model source rate and Mach number are found to vary considerably among different sources during the same flyby and also among different flybys for the same source, revealing a complicated spatio-temporal variability in the plume structure. Our analysis suggests a total escape rate of (1.0–7.1) × 1026 s−1 for CO2 and (2.4–6.6) × 1028 s−1 for H2O, in broad agreement with previous estimates. Of particular interest is our identification of a tentative correlation between the Mach number and thermal brightness, of which the latter is a tracer of the geological activity of the emission source. Such a relation should be able to provide more insights into the nature of geyser emission along the ‘tiger stripes’.

The Millennium Eruption (ME) of Changbaishan volcano (Baitoushan, Paektu) at 946 CE (Common Era) is one of the largest explosive eruptions on Earth during Holocene times. We date unpolished zircon crystal faces from diverse ME products collected from the southern side of Changbaishan volcano where the ME pumice and welded and non-welded pyroclastic flow deposits (PFD) are better exposed. All zircons from a pumice sample of the southern caldera rim and the youngest (Group 1) zircons from a welded pumiceous PFD sample yield an isochron crystallization age of 0.7 ± 1.8 ka (2σ). Zircons from the welded pumiceous PFD sample yield additional two age groups at ~10 ka and ~ 100 ka. Zircons from a non-welded charcoal-containing PFD have only one age population at 100 ka. Our work shows that different eruption products from ME have different zircon surface age distributions and may tap different levels of a zoned felsic magma chamber. In addition, the results indicate that ion microprobe U-Th dating of zircon crystal surfaces from ME pumices can effectively date the Millennium eruption age. Previously reported zircon U-series ages for Qixangzhan eruption (12.2 ± 1.1 ka, 2σ) and Yuanchi eruption (7.3 ± 1.8 ka, 2σ) at Changbaishan are also likely to date their respective eruption ages. The occurrence of 100 ka zircons in welded and non-welded PFDs reveals an important magmatic event for the Changbaishan volcano. Zircon and Fe-rich clinopyroxene crystallized at similar temperature at 770–750 °C, indicative of early zircon crystallization in peralkaline magmas. Another important result is the extremely low oxygen fugacity (fO2 = ΔFMQ-2) of the Changbaishan samples. Minerals in ME magmas were crystallized under some of the most reducing magmatic environments on Earth. Highly reducing conditions of magmas from Changbaishan supports a continental rift setting and argues against significant involvements of subduction-related oxidizing fluids during magma genesis.

In this paper, we study flows of hypersurfaces in hyperbolic space, and apply them to prove geometric inequalities. In the first part of the paper, we consider volume preserving flows by a family of curvature functions including positive powers of $k$-th mean curvatures with $k=1,\cdots,n$, and positive powers of $p$-th power sums $S_p$ with $p>0$. We prove that if the initial hypersurface $M_0$ is smooth and closed and has positive sectional curvatures, then the solution $M_t$ of the flow has positive sectional curvature for any time $t>0$, exists for all time and converges to a geodesic sphere exponentially in the smooth topology. The convergence result can be used to show that certain Alexandrov-Fenchel quermassintegral inequalities, known previously for horospherically convex hypersurfaces, also hold under the weaker condition of positive sectional curvature. In the second part of this paper, we study curvature flows for strictly horospherically convex hypersurfaces in hyperbolic space with speed given by a smooth, symmetric, increasing and homogeneous degree one function $f$ of the shifted principal curvatures $\lambda_i=\kappa_i-1$, plus a global term chosen to impose a constraint on the quermassintegrals of the enclosed domain, where $f$ is assumed to satisfy a certain condition on the second derivatives. We prove that if the initial hypersurface is smooth, closed and strictly horospherically convex, then the solution of the flow exists for all time and converges to a geodesic sphere exponentially in the smooth topology. As applications of the convergence result, we prove a new rigidity theorem on smooth closed Weingarten hypersurfaces in hyperbolic space, and a new class of Alexandrov-Fenchel type inequalities for smooth horospherically convex hypersurfaces in hyperbolic space.

Rainfall impacts local water quantity and quality. Accurate and timely prediction of rainfall is highly desirable in water management and hydrogeologic hazards mitigation, which is critical for the environmentally sustainable development. Previous rainfall prediction processes are complex and computationally costly for its intrinsic high uncertainty and variability. In this paper, a data-driven approach is applied to predict the rainfall based on historic data via time-series modeling and optimally pruned extreme learning machine (OP-ELM). The rainfall datasets collected from six counties within Three Georges Reservoir are utilized as case studies in this research, first, the rainfall data is pre-processed with outlier removal and missing value imputation, and the monthly ahead difference is computed based on the instant average of monthly rainfall. Next, the autocorrelation function and partial autocorrelation function were computed and the Ljung–Box test statistic is utilized to explore the significance of the historic lagged-series. All the statistically significant historic lags are selected as inputs for prediction algorithms. Last, an OP-ELM algorithm is developed to predict the monthly rainfall with tenfold cross validation. Four activation functions: the sigmoid, sine, hardlim, and radial basis function, are considered in the OP-ELM. The prediction performance is evaluated with metrics including mean absolute error, mean absolute percentage error, root mean square error, and max error rate. Overall, the computational results indicate the proposed framework outperforms the other benchmarking machine learning algorithms through six case studies in Three Gorges Reservoir, China.

Polymer blends with synergetic performance play an integral part in modern society. The discovery of compatible polymer systems often relies on strong chemical interactions. By contrast, the role of entropy in polymers is often neglected. In this work, we show that entropy effect could control the phase structure and mechanical behaviors of polymer blends. For weakly interacting polymer pairs, the seemingly small mixing entropy favors the formation of nanoscale cocontinuous structures. The abundant nanointerfaces could initiate large plastic deformations by crazing or shear, thus, transforming brittle polymers (elongation9%) into superductile materials (elongation ∼ 146%). The resultant polymer blends display high transparency, strength (∼70 MPa), and toughness (∼60 MJ/m

The qualitative relationship between hydrogen concentration and notch tensile strength has been investigated for 5Ni-16Cr-Mo steel with different strength. The notch tensile strength was determined by means of slow strain rate test (SSRT) on circumferentially notched round bar specimens with the notch root radius of 0.15 mm after hydrogen charging. Meanwhile, the hydrogen diffusion behaviors of various strength steel were studied by thermal desorption spectroscopy (TDS) analysis. The SSRT results show that the T460 steel has higher susceptibility of hydrogen embrittlement in contrast with T520 steel. The activation energies and microstructure indicate that the dislocations and interfaces of martensitic laths are hydrogen traps in 5Ni-16Cr-Mo steel. By SSRT, the elastic limit of charged specimen loaded in air is higher than the flow stress without hydrogen charging before unloading, while the difference is defined as hydrogen-induced stress. The value of hydrogen-induced stress σ* increases linearly with hydrogen concentration: σ*=−0.622+2.015C0. The finite element analysis results of stress distributions near the notch tip have shown that the maximum principal stress increases with the notch root radius decreasing.

Vanadium-based oxide is widely investigated as a zinc ion battery (ZIB) cathode due to its ability to react reversibly with Zn2+. Despite its successful demonstration, modification with simple molecules has shown some promise in enhancing the performance of ZIBs. Thus, this presents an immense opportunity to explore simple molecules that can dramatically improve the electrochemical performance of electrodes. Thus, the effect of CO2 modification is studied in this work by decomposing oxalic acid within a hydrated V6O13 framework. Based on the collective results, the presence of CO2 drastically lowers the relative energy of Zn2+ diffusion through the pathways by forming weak electrostatic interactions between OCO2 and Zn2+. This leads to an enlarged diffusion contribution, which consequently results in enhanced stability and better rate performance. The as-synthesized CO2-V6O13 electrode delivers one of the highest specific capacities reported for vanadium-based oxides of ca. 471 mAh g-1. Furthermore, an excellent cyclic stability of 80% capacity retention after 4000 cycles at 2 A g-1 is recorded for CO2-V6O13, which suggests the importance of simple molecules in the material framework toward the enhancement of ZIB cathode performance.

By direct electrospinning poly(vinylidene fluoride) (PVDF)/Si3N4 blend solution on the Na2Ni[Fe(CN)6] electrode, a flexible separator@electrode combination is obtained. This combination is closely cross-linked by the -CH2 CF2- chain of β-PVDF in the separator and electrode, which delivers unique advantages in flexibility, thermal stability, tensile strength and interfacial resistance. Meanwhile, the PVDF/Si3N4 separator has a higher porosity (84.2%) and ionic conductivity (4.1 × 10−3 S cm−1), making the combination display an excellent electrochemical performance with a high initial coulombic efficiency of 96.8%, capacity retention rate of 92.2% after 503 cycles and rate capability of 78 mAh g − 1 at 5 C.

Discrete element modelling (DEM) and experimental characterization were carried out for Hall flowmeter tests, in which Inconel718 powders were poured down through a funnel into a density cup to form a heap. By measuring the flow rate, angle of repose and packing fraction from the experiments, and combining with DEM simulations, we were able to extract the coefficients of friction for the powder-powder and powder-wall interactions. We further studied the effect of powder-powder adhesion and found that the adhesion could greatly affect the flow rate and flow pattern. In particular, by increasing the adhesion, we observed a transition from a continuous to discontinuous discharging flow, and revealed an underlying mechanism for the transition. We also studied the effects of powder size and density cup diameter, and found that at their application size scale, the influences of these parameters on the measured results are negligible. The present work presents a simple approach to study the intrinsic properties of powders, and their influences on flowability and packing property.

Objective To screen several immune-related long non-coding RNAs (lncRNAs) and construct a prognostic model for papillary renal cell carcinoma (pRCC). Methods Transcriptome-sequencing data of pRCC was downloaded and a prognostic model was constructed. Time-dependent receiver operating characteristic (ROC) curve was plotted and the area under curve (AUC) was calculated. We conducted quantitative reverse transcription polymerase chain reaction (RT-PCR) to verify the model. The gene set enrichment analysis (GSEA) was used to show the connection of our model with immune pathways. Result We identified four lncRNAs to constructed the model. The model was significantly associated with the survival time and survival state. The expression-levels of the four lncRNAs were measured and the prognosis of high-risk patients was significantly worse. The two immune-gene sets had an active performance in the high-risk patients. Conclusion We constructed a prognostic model in pRCC which provided more reference for treatment.

A novel carbon allotrope is predicted by first-principles calculations. This allotrope is obtained by replacing one of the two atoms in the primitive cell of diamond with a carbon tetrahedron, thus it contains five atoms in one primitive cell, termed T5-carbon. The stabilities of T5-carbon are checked in structural, thermal and vibrational calculations. T5-carbon is a wide band gap semiconductor with an indirect band gap of 4.30 eV, and has a lattice thermal conductivity of 409 W/mK. Mechanical analyses reveal that T5-carbon shows good mechanical performances. Furthermore, by modifying T5-carbon with replacing some carbon atoms with Si or Ti atoms, we can obtain SiC4 or TiC4 structures. Importantly, the TiC4 system has a moderate conduction and valance band edges, comparable larger absorption capacity of visible light and smaller effective masses of electron and hole carriers than TiO2, confirming its photocatalysis applications.

The effects of l-tryptophan supplementation on secondary metabolite production in the marine-derived fungus Fusarium sp. L1 were investigated by culturing the fungus in GPY medium with and without the amino acid. HPLC analysis of the products showed distinct metabolite profiles between the two cultures. The 1H NMR spectrum of the EtOAc extract of the culture supplemented with l-tryptophan displayed a series of characteristic aromatic proton signals (δH 6.50-8.50) and NH signals (δH 10.50-11.50) that were not observed in those from cultures not supplemented with l-tryptophan. Subsequently, 23 distinct indole alkaloids, including six new compounds, fusaindoterpenes A and B (1 and 2), fusariumindoles A-C (3-5), and (±)-isoalternatine A (6), together with 17 known compounds, were obtained from this culture. Fusaindoterpene A (1) contains a 6/9/6/6/5 heterocyclic system. Their chemical structures were determined by analysis of HRMS, NMR spectroscopy, optical rotation calculation, ECD calculation, and single-crystal X-ray diffraction data. Compounds 2, 9, and 15 displayed inhibitory activity against the Zika virus (ZIKV) in a standard plaque assay with EC50 values of 7.5, 4.2, and 5.0 μM, respectively, while not showing significant cell cytotoxicity against the A549 adenocarcinomic human alveolar basal epithelial cell line.

Understanding protein corona formation in an aqueous environment at the molecular and atomistic levels is critical to applications such as biomolecule-detection and drug delivery. In this work, we employed mesoscopic coarse-grained simulations to study ovispirin-1 and lysozyme protein coronas on bare gold nanoparticles. Our study showed that protein corona formation is governed by protein-surface and protein-protein interactions, as well as the surface hydrophobic effect. The corona structure was found to be dependent on protein types and the size of nanoparticles. Ovispirin proteins form homogeneous single-layered adsorption in comparison with the lysozyme's inhomogeneous multilayered aggregates on gold NP surfaces. The decrease in nanoparticle size leads to more angular degrees of freedom for protein adsorption orientation. Subsequent atomistic molecular dynamics simulations further demonstrate the loss of secondary structure of ovispirin upon adsorption and the heterogeneity of its local structure.

An improved precipitation method - electrostatic spray precipitation is proposed, which is characterized by introducing the electrostatic atomization effect into the precipitation process. The results display that electrostatic atomization can effectively reduce the size of reaction solution droplets under electrostatic force, the growth process of crystal nucleus is optimized, and then flake cluster MnCO3 is obtained, which further promotes the formation of homogeneous MnO nanoparticles. Compared with the agglomerated MnO without electrostatic action, homogeneous MnO nanoparticles exhibit better cycling stability (787 mAh g−1 after 100 cycles at 377.5 mA g−1) and rate capability (471 mAh g−1 at 3020 mA g−1).

Background Leaf senescence comprises numerous cooperative events, integrates environmental signals with age-dependent developmental cues, and coordinates the multifaceted deterioration and source-to-sink allocation of nutrients. In crops, leaf senescence has long been regarded as an essential developmental stage for productivity and quality, whereas functional characterization of candidate genes involved in the regulation of leaf senescence has, thus far, been limited in wheat. Results In this study, we analyzed the expression profiles of 97 WRKY transcription factors (TFs) throughout the progression of leaf senescence in wheat and subsequently isolated a potential regulator of leaf senescence, TaWRKY42-B, for further functional investigation. By phenotypic and physiological analyses in TaWRKY42-B-overexpressing Arabidopsis plants and TaWRKY42-B-silenced wheat plants, we confirmed the positive role of TaWRKY42-B in the initiation of developmental and dark-induced leaf senescence. Furthermore, our results revealed that TaWRKY42-B promotes leaf senescence mainly by interacting with a JA biosynthesis gene, AtLOX3, and its ortholog, TaLOX3, which consequently contributes to the accumulation of JA content. In the present study, we also demonstrated that TaWRKY42-B was functionally conserved with AtWRKY53 in the initiation of age-dependent leaf senescence. Conclusion Our results revealed a novel positive regulator of leaf senescence, TaWRKY42-B, which mediates JA-related leaf senescence via activation of JA biosynthesis and has the potential to be a target gene for molecular breeding in wheat.

Adopting ICP-AES and ICP-MS to determine the content of 53 elements (6 macro-elements, 47 trace elements), which used HNO3 (5 mL) and H2O2 (2 mL) to digest Baishao (Paeoniae Radix Alba) by microwave. These herbs obtained from six producing areas in China, namely Xuanwu (Henan province), Shihezi (Xinjiang province), Zhongjiang (Sichuan province), Panan (Zhejiang province), Bozhou (Anhui province), and Heze (Shandong province). A certified reference material of Astragalus (GBW 10028, GSB-19) was used to assess the accuracy of the method. Except the slight change of Na and S in Xuanwu, the content of other producing areas followed the order of Ca > K > P > Mg > S > Na. The herbs of Shihezi (22,658 mg/kg) got the highest concentration of total elements, while the herbs of Panan (1.006 mg/kg) got the highest concentration of rare earth elements. The multi-element fingerprint map of Baishao was established, which was obviously different from other herbs. Meanwhile, the same method was adopted to determine the content of 50 elements in Baishao decoctions from three main producing areas. Compared with the herbs, each element was significantly reduced, and K was the highest concentration. The transfer rates of elements in Baishao decoctions followed the order (mean): As (55.79%) > Ni (55.19%) > Na (51.48%) > Mo (44.13%) > Ce (43.82%) > V (40.52%). The decoctions of Panan (0.122 mg/kg) got the highest content of rare earth elements. In all Baishao herbs and their corresponding decoctions, the levels of Cu, Cd, As, Pb, and Hg did not exceed the limits of the Green Trade Standards of Importing & Exporting Medicinal Plants & Preparations (WM2-2001) and Chinese Pharmacopoeia (2015).

Hydrogen peroxide (H2O2) is an important product generated in the body and related to many pathophysiological processes and glucose metabolism disorder can cause many fatal diseases in living bodies. Therefore, the sensing of H2O2 and glucose is of great significance in disease diagnostics and treatment. Fluorescent carbon dots (CDs) are one new class of nanoprobes for H2O2 and glucose. Nevertheless, the CD-based sensor is always based on its fluorescence response, which is influenced by the auto-fluorescent interference. Herein, efficient fluorescent CDs were synthesized by one-pot solvothermal method, and the CDs exhibit bright and persistent deep-red (DR) chemiluminescence (CL) in bis(2,4,6-trichlorophenyl) oxalate and H2O2 solution with a CL quantum yield of (8.22 ± 0.30) × 10−3, which is amongst the highest values in ever reported nanomaterials for chemical analysis. Employing the CDs as CL nanoprobes, sensitive sensing for H2O2 has been achieved with a detection limit of 11.7 μM, and further for glucose detection with a detection limit of 12.6 μM. The DR CL CDs is promising to be applied in blood glucose analysis or in vivo biosensor.

The occurrence forms of organic nitrogen in Xianfeng lignite (XL), Xiaolongtan lignite (XLT) and Shengli lignite (SL) as well as their extraction residues were characterized by X-ray photoelectron spectroscopy (XPS). The results show that the content distributions of organic nitrogen in the three extraction residues are different, but all are mainly dominated by pyrrolic nitrogen. The NaOH-catalyzed supercritical methanolysis of lignite extraction residues at 300°C was then investigated, which indicates that the yields of petroleum ether soluble portions from supercritical methanolysis of extraction residues derived from XL, XLT and SL are 46.0%, 43.8%, and 47.6%, respectively. The characterization of nitrogen-containing compounds (NCCs) in petroleum ether soluble portions by Fourier transform ion cyclotron resonance mass spectrometry (FTICR/MS) indicates that NCCs are mainly composed of N1, N1O1-N1O5, N2, N2O1-N2O4, N3O2 and N5O2-N5O4 class species. The molecular structural characteristics of NCCs were speculated according to the distributions of double bond equivalent values and carbon numbers, which shows that most of NCCs contain oxygen-functional groups like hydroxyl and carboxyl groups, and the nitrogen atoms are mainly present in aromatic structures (mainly 1–3 aromatic rings) in the forms of pyrrolic, pyridinic and amino groups. The cleavage of C-O bridged bonds in lignite is an important pathway for producing NCCs.

The development of infrared photodetectors is mainly limited by the choice of available materials and the intricate crystal growth process. Moreover, thermally activated carriers in traditional III-V and II-VI semiconductors enforce low operating temperatures in the infrared photodetectors. Here we demonstrate infrared photodetection enabled by interlayer excitons (ILEs) generated between tungsten and hafnium disulfide, WS2/HfS2. The photodetector operates at room temperature and shows an even higher performance at higher temperatures owing to the large exciton binding energy and phonon-assisted optical transition. The unique band alignment in the WS2/HfS2 heterostructure allows interlayer bandgap tuning from the mid- to long-wave infrared spectrum. We postulate that the sizeable charge delocalization and ILE accumulation at the interface result in a greatly enhanced oscillator strength of the ILEs and a high responsivity of the photodetector. The sensitivity of ILEs to the thickness of two-dimensional materials and the external field provides an excellent platform to realize robust tunable room temperature infrared photodetectors. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) National Research Foundation (NRF) Accepted version The work is supported by the Agency for Science, Technology and Research (A*STAR) under the 2D Materials Pharos Program (grant no. 152 700014 and grant no. 152 700017). Q.J.W. acknowledges funding from the National Research Foundation Competitive Research Program (NRF-CRP18-2017-02 and NRF–CRP19–2017–01). K.S.T. acknowledges support from the Center for Nanostructured Graphene (CNG) under the Danish National Research Foundation (project DNRF103) and from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant no. 773122, LIMA). G.L. acknowledges the supported under the grant MOE2017-T2-1-114. H.L. acknowledges the support by the Ministry of Science and Technology (MOST) in Taiwan under grant no. MOST 109-2112-M-001-014-MY3. J.T. and S. Lukman thank C. W. Lee, A. Ngo and M. Zhao for their valuable inputs and K Hippalgaonkar for sharing tools in the device fabrication.

An effective deep eutectic solvent (DES) combined with column chromatography was designed for separating nitrogen-containing aromatics (NCAs) from the light portion (LP, which is petroleum-ether-ex...

The surface OH groups decorated monoclinic SrAl2O4 nanoparticles, Ce and Ce,Mn co-doped SrAl2O4 were synthesized by a gamma-ray irradiation assisted polyacrylamide gel method. The obtained material was used to study the color and optical properties and for the photocatalytic degradation of Congo red (CR) dye. The color and optical properties shows that the surface OH groups decorated SrAl2O4 nanoparticles is a potential white pigment. The Ce or Ce, Mn doping reduced the Eg value and significantly changed the light absorption capacity, the recombination rate of photogenerated carriers, photoluminescence properties and photocatalytic activity of SrAl2O4. Laser Raman spectroscopy shows three obvious luminescent background peaks at 398, 408, and 430 nm for the surface OH groups decorated SrAl2O4 nanoparticles. The photoluminescence spectrum detected at λex = 295 nm shows four luminescence peaks located at 330, 368, 420, and 468 nm for the SrAl2O4:Ce and SrAl2O4:Ce:Mn samples. The SrAl2O4:Ce:Mn phosphor have a high photocatalytic activity for the photodegradation of CR dye can be ascribed to the synergistic effects of the band edge position, light absorption capacity, utilization and separation efficiency of photogenerated carriers.

Coal tar pitch (CTP) with high carbon content and wide source of raw materials was an excellent precursor for the preparation of porous carbons (PCs). CTP was composed of polycyclic aromatic hydrocarbons (PAHs) with complex molecular size and chemical structure, the separation of CTP into several fractions with relatively narrow molecular weight by solvent extraction was of significance for CTP utilization. In this paper, CTP was treated by single-solvent extraction (carbon disulfide, acetone and ethyl acetate), and the six fractions were used as raw materials to prepare PCs as electrode material for electric double layer capacitor. The fractions were well characterized and the effect of mass distribution of different narrow fractions on structure property and electrochemical performance of the PCs was studied. The PCs prepared by carbon disulfide extract, acetone raffinate and ethyl acetate extract, containing more PAHs, exhibited the excellent specific capacitance performance in comparison with its residual components. The remarkable performance might contribute in the enhanced transport of electrolyte ions via the molecular graphene structure of PAHs. Additionally, the PC prepared by carbon disulfide raffinate showed outstanding cycling performance (99.7% at 2 A g-1 after 15,000 cycles) which was related to its unique layered porous structure.

The ability of cucurbit[6]uril (CB6) and cucurbit[7]uril (CB7) to catalyze the thermally activated 1,2-methyl shift isomerization pathway of m-xylene in vacuum is investigated using infrequent metadynamics. CB6 is predicted to effectively and selectively catalyze the meta-to-para isomerization through stabilization of the transition state (TS) by van der Waals push (packing coefficient ≈74%), while inhibiting the meta-to-ortho pathway by molding effects of the cavity. Interestingly, despite the snug binding, a very low rate of host–guest vibrational energy transfer is revealed using a novel approach of host–guest partition of the mode-specific anharmonic relaxation rates and ab initio molecular dynamics. The weak vibrational coupling suggests that CB can act as a thermal buffer, possibly shielding encapsulated guests from outside vibrational perturbations such as solvent effects. This dynamic effect could provide an additional boost to the reaction rate by blocking the occurrence of reaction barrier recrossing caused by the friction with surrounding molecules. Finally, mean residence times of xylene into the hosts’ cavity were estimated for a range of host–guest complexes, revealing a highly dynamic equilibrium allowing very high guest turnover rates that could minimize catalyst inhibition effects commonly suffered by other supramolecular catalysts.

The most fantastic optical phenomena in the Earth's upper atmosphere are the auroras. They are highly informative indicators of solar activity, geomagnetic activity, upper atmospheric structures and dynamics, and magnetospheric energetic particles. An area where the geomagnetic field differs significantly from the expected symmetric dipole, such as at the South Atlantic Anomaly, where the magnetic field intensity is low, gives rise to stronger precipitation of energetic particles into the upper atmosphere. Impact excitation and the subsequent airglow emissions exhibit aurora-like dynamic signatures. Nomenclatures of nonpolar aurora or equatorial auroras are similar to those used with the polar auroras owing to their similar excitation mechanisms. This paper provides an overview of the knowledge and the challenges concerning auroral activity at the South Atlantic Anomaly, or more generally, at the negative magnetic anomaly. We emphasize systematic investigation of the equatorial auroras to reveal the temporal and spatial evolution of the magnetic anomaly and the behaviour of energetic particles in near-Earth space.

Purpose This paper aims to clarify the relationship between the performance of the metal nanoparticles and the sensitivity of the fiber surface plasma resonance (SPR) sensor. It proposes modeling the sensing effects of a single-mode fiber SPR sensor with a cone angle structure decorated with metal nanoparticles. This study uses the metal nanoparticles to the realize enhanced sensitivity of refractive index sensing. Design/methodology/approach This paper opted for an exploratory study using a simulation approach of finite-difference time-domain (FDTD). Specifically, the effect of size, the material and the shape of the metal nanoparticle on sensing performance are investigated theoretically. Findings In conclusion, it is evident that the localized SPR (LSPR) effect weakens as the diameter of the gold nanosphere increases, the SPR effect enhances and the SPR sensitivity increases first and then decreases. The metal nanoparticle with the different materials and different shapes also have different LSPR and SPR sensitivity and wavelength length dynamic range. The investigation shows that, by changing parameters, the reflection spectra of the fiber SPR sensor exhibit an obvious transition from LSPR to SPR characteristics, and enhanced sensitivity of the refractive index is realized. Originality/value This paper fulfills an identified need to study how the sensitivity of the fiber SPR sensor can be enhanced by the metal nanoparticle. After the optimization of parameters, the sensitivity of 5,140 nm/RIU is achieved, which provides a new research direction for sensitivity enhancement of fiber SPR sensor.

Phytic acid-doped copolymers poly(aniline-co-pyrrole) have been synthesized by chemical polymerization for applications of supercapacitors. The results indicate that poly(aniline-co-pyrrole) copolymer delivered a high specific capacitance (639 F g−1) and 62.3% capacitance retention after 1000 cycles at 3 A g−1 in 1 M H2SO4. The good cycle stability was due to increased structural stability by the formation of cross-link between poly(aniline-co-pyrrole) backbones doped by phytic acid. The high capacitance may result from the formation of large specific surface area and effective conducting paths in the copolymer. A symmetrical supercapacitor device based on this copolymer was designed and provided a high energy density (12.2 Wh kg−1 at the power density of 500 W kg−1). Such results indicate that poly(aniline-co-pyrrole) might be a feasible candidate for electrocapacitive material of supercapacitors and this strategy can be extended to fabricate other conducting polymers for supercapacitor applications.

The authors design six alumina hybrid structures consisting of stretching-dominated plates and different space-filling lattices comprised of hollow tubes and perform finite element simulations to study mechanical and failure behaviors of such hybrid structures. The authors investigate the effects of three geometrical parameters on the stiffness and failure of these hybrid structures and further compare their advantages and disadvantages. The authors find that the failure modes of these hybrid structures can be tuned by altering cell unit type and geometrical parameters. Among these hybrid structures, the ones with effective support from the lattice unit cells in the stretching direction exhibit better specific stiffness and strength. By varying the lattice and plate thickness, the authors find that the relations between stiffness/failure strength and density follow a power law. When intrinsic material failure occurs, the power law exponent is 1; when buckling failure arises, the power law exponent is 3. However, by varying tube thickness, their relations follow unusual power relations with the exponent changing from nearly 0 to nearly infinity. In addition, the hybrid structures also exhibit defect insensitivity. This study shows that such hybrid structures are able to greatly expand the design space of architectured cellular materials for engineering applications.

Introduction The bone regeneration of endosseous implanted biomaterials is often impaired by the host immune response, especially macrophage-related inflammation which plays an important role in the bone healing process. Thus, it is a promising strategy to design an osteo-immunomodulatory biomaterial to take advantage of the macrophage-related immune response and improve the osseointegration performance of the implant. Methods In this study, we developed an antibacterial silver nanoparticle-loaded TiO2 nanotubes (Ag@TiO2-NTs) using an electrochemical anodization method to make the surface modification and investigated the influences of Ag@TiO2-NTs on the macrophage polarization, osteo-immune microenvironment as well as its potential molecular mechanisms in vitro and in vivo. Results The results showed that Ag@TiO2-NTs with controlled releasing of ultra-low-dose Ag+ ions had the excellent ability to induce the macrophage polarization towards the M2 phenotype and create a suitable osteo-immune microenvironment in vitro, via inhibiting PI3K/Akt, suppressing the downstream effector GLUT1, and activating autophagy. Moreover, Ag@TiO2-NTs surface could improve bone formation, suppress inflammation, and promote osteo-immune microenvironment compared to the TiO2-NTs and polished Ti surfaces in vivo. These findings suggested that Ag@TiO2-NTs with controlled releasing of ultra-low-dose Ag+ ions could not only inhibit the inflammation process but also promote the bone healing by inducing healing-associated M2 polarization. Discussion Using this surface modification strategy to modulate the macrophage-related immune response, rather than prevent the host response, maybe a promising strategy for implant surgeries in the future.

Porous interconnected carbon nanosheets (PICNs) with high electrochemical performance were prepared by doping urea and a co-hydrothermal precursor derived from soybean stalk (SS) and nickel nitrate. The specific surface area and average pore diameter of the as-synthesized PICNs are 2226.29 m2 g−1 and 1.89 nm, and their N and O contents are 5.08% and 9.4%, respectively, which is beneficial for increasing pseudocapacitance. Furthermore, the doping of the metal Ni increases the graphitization degree of the PICNs and promotes the conversion of pyridine-N to graphitized-N. Therefore, the PICNs possess a high specific capacitance of 407 F g−1 at a current density of 0.5 A g−1, a high capacitance retention of 78.62% even at 20 A g−1, and an outstanding cycling stability (over 93% retention rate after 10,000 charge/discharge cycles). Moreover, an energy density of 36.11 W h kg−1 is achieved at a power density of 517.8 W kg−1 during a two-electrode system test, and a retention rate of 87.5% is obtained after 10,000 cycles. This co-hydrothermal treatment as well as nitrogen-doping approach for preparing porous interconnected carbon from SS not only represents an alternative strategy for carbon-based supercapacitor materials but also provides a new option for the utilization of waste SS.

In this paper, a low-dimensional hidden nonlinear system is constructed by replacing two linear resistors of a simple integrating circuit with two active memristors. The system was analyzed in detail by using the Lyapunov exponent, 0–1 Test, Poincare map, phase diagram, power spectral density diagram, time-domain waveform, and chaotic characteristic diagram. The results show that the system can oscillate by itself under zero initial conditions, and there are various transient transition behaviors, such as from chaos to limit cycle, chaos to quasi-periodic, quasi-periodic to another quasi-periodic transition, quasi-periodic to periodic transition. Besides, these transient processes themselves include 2, 3, 4, and 5 different states respectively, showing multiple transient transitions behavior, which are not reported in the related literature. It is also found that the initial states of these transition states have rich symmetrical attractors and the stable state is multistability. In addition, the global entropy analysis method is adopted to test the universal existence of transient behaviors, which demonstrates that the system has rich nonlinear characteristics. Finally, the memristive circuit verifies the system’s physical feasibility and enriches the application of memristors in circuit theory.

Two-dimensional (2D) transition-metal dichalcogenides (TMDs) hold great potential for many important device applications, such as field effect transistors and sensors, which require a robust control of defect type, density, and distribution. However, how to control the defect type, density, and distribution in these materials is still a challenge. In this study, we explore the kinetics and dynamics of four types of grain boundaries (GBs) in monolayer MoS2, which are composed of S-polar dislocation (S5|7), Mo-polar dislocation (Mo5|7), dislocation-double S vacancy complex (S4|6), and dislocation-double S interstitial complex (S6|8), respectively. Our study shows that these four GBs in monolayer MoS2 exhibit a great disparity in their migration behavior. More specifically, the S4|6 and S6|8 GBs possess a much higher migration mobility than the S5|7 and Mo5|7 GBs under the same thermal fluctuations or temperature gradient. Interestingly, the S4|6 and S6|8 GBs follow an abnormal relationship with temperature, due to the change in defect configurations with temperature. Our study further shows that the remarkably high mobilities of the S4|6 and Mo6|8 GBs may enable the reactions of GBs, leading to the annihilation and reduction of defect density. In addition, the movement of GBs in MoS2 under a temperature gradient field can cause defect redistribution, which in turn changes the thermal conductivity. The present study not only deepens our understanding of the dynamic evolution of GBs in TMDs, but also presents new opportunities to engineer GBs for novel electronic applications.

As one of the most intriguing elemental 2D materials beyond graphene, stanene is a unique material possessing strong quantum spin Hall effect and is promising for spintronics applications. Since most of these exotic phenomena are associated with the edge states of stanene and their responses under external stimuli, here, we first investigate the electronic and transport behavior of the edge states of stanene. Through examining the acoustic phonon-limited scattering of transporting carriers, we reveal a staggering behavior in the effective mass and mobility varying with the width of stanene nanoribbons. Remarkably, an opposite oscillating trend of the quantum confinement effect with respect to the electrons and holes is found and this trend is in sharp contrast to graphene. Moreover, through group-theory analysis, we further analyze the symmetry-permitted light absorptions and predict a much smaller band gap at Γ compared with other IV-group 2D materials like graphene and silicene, allowing for a red-shift of optical π-π* absorption in stanene. The presence of the narrow flat bands along the M-K path in stanene suggests appreciable density of states of low-energy carriers and a strong light-matter interaction for low-energy photons, which are beneficial for its applications in low-frequency optoelectronics.

The effects of a single-amino-acid culture strategy on secondary metabolite production in the marine-derived fungus Trichoderma erinaceum F1-1 were investigated by culturing the fungus in GPY medium supplemented or not supplemented with l-phenylalanine. A suite of secondary metabolites, including seven terpenoids (1-7) and one polyketide (8), among which are four new compounds, harziandione A (1), cyclonerodiols A and B (3, 4), and trichodermaerin A (6), were isolated from the GPY medium without l-phenylanine, whereas 18 aromatic compounds (9-26), including six new compounds, trichoderolides A-F (9, 10, and 14-17), were isolated from the culture grown in the GPY medium with l-phenylalanine. The structures of the new compounds were determined by high-resolution mass spectrometry, NMR spectroscopic analysis, optical rotation calculations, chemical methods, and X-ray crystallography. Compounds 10, 12, 13, and 26 exhibited cytotoxic activities against MDA-MB-435 human melanocyte cancer cells. Compound 26 was cytotoxic to A549 adenocarcinomic human alveolar basal epithelial cells.

To overcome the drawbacks of pyrolytic bio-oil, such as high acidity, viscidity, corrosivity, oxygen content and low heating value, a novel method of emulsifying bio-oil with diesel was investigated in this study. The effects of various factors on the stability of emulsified oil were examined. The optimal emulsification conditions of diesel and bio-oil are by using an emulsifier (mixture of Span 80 and Tween 80) dosage of 6% by mass and co-emulsifier (2-octanol) dosage of 4% by the mass of emulsifier, hydrophile lipophilic balance value of 7, shear velocity of 15,000 rpm, emulsifying time of 5 min, and emulsifying temperature at 40 °C. The stability time of emulsified oil is up to 384 h under the above optimal conditions. Some fuel properties were also measured to characterize the emulsified oil. The results show that the density, viscosity, corrosivity and heating value of emulsified oil at the optimal conditions are close to those of diesel oil. In addition, the mechanism model for the emulsion of bio-oil and diesel was also proposed.

This paper presents the research of water holdup detection in oil-water two-phase flows and sensor design based on coplanar microstrip transmission line (also known as coplanar waveguide, CPW). The relationship between the CPW structure/material parameters and electromagnetic wave propagation characteristics was analyzed using conformal transformation method. Adopting double-sided and S-shaped wiring sheet structure, the dynamic range of detection is improved while the structure of the sensor is miniaturized. Therefore, multiple sensors can be arranged on the cross-section of the oil well to form a detection array, which can provide differential information of water holdup on the cross-section of horizontal wells or highly deviated wells and improve the spatial resolution of the measurement. Numerical simulations and experimental results show that the phase shifts of the signal detected by sensors are approximately linearly proportional to the water holdup of the measured fluid, the resolution is up to 3% in the whole range of water holdup from 0% to 100%. This method makes up for the disadvantages of capacitance method and conductance method, which are only effective for low water holdup and high holdup scenarios respectively.

Graphene-based layered materials have attracted particular interests recently owing to their excellent mechanical and thermal properties, which are attributed to their layer-by-layer hierarchical structures with intralayer strong sp2 bonds combined with interlayer crosslinks for efficient load and heat transfer. They have many potential applications such as high thermal conductive films in flexible electronics. In this paper, we firstly develop an analytical model to calculate the thermal conductivity of graphene layered materials. Then, extensive molecular dynamics simulations are performed to validate the analytical model. A good agreement is obtained between the analytical and simulation results. Besides, the effects of geometry factors such as graphene sheet size and crosslink density on the temperature distribution and thermal conductivity of graphene layered materials are investigated. It is found that the thermal conductivity of graphene layered materials can be effectively tuned by the graphene sheet size and crosslink density. Our works are of practical importance for the design and application of graphene layered materials as thermal film materials.

We present an investigation of the disturbance history of an old-growth Douglas-fir (Pseudotsuga menziesii) stand in South Beach, Oregon, for possible growth changes due to tsunami inundation caused by the 1700 CE Cascadia Subduction Zone (CSZ) earthquake. A high-resolution model of the 1700 tsunami run-up heights at South Beach, assuming an “L”-sized earthquake, is also presented to better estimate the inundation levels several kilometers inland at the old-growth site. This tsunami model indicates the South Beach fir stand would have been subjected to local inundation depths from 0 to 10 m. Growth chronologies collected from the Douglas-fir stand shows that trees experienced a significant growth reductions in the year 1700 relative to nearby Douglas-fir stands, consistent with the tsunami inundation estimates. The ±1–3-year timing of the South Beach disturbances are also consistent with disturbances previously observed at a Washington state coastal forest ∼220 km to the north. Moreover, the 1700 South Beach growth reductions were not the largest over the >321-year tree chronology at this location, with other disturbances likely caused by climate drivers (e.g., drought or windstorms). Our study represents a first step in using tree growth history to ground truth tsunami inundation models by providing site-specific physical evidence.

Planetary science is the scientific investigations of the basic characteristics and the formation and evolution processes of the planets, moons, comets, asteroids and other minor bodies of the solar system, the exoplanets, and the planetary systems. Planetary scientific research mainly depends on deep space exploration, and it is highly interdisplinary and is built from Earth science, space science, astronomy and other relevant disciplines. Planetary space, a critical region of mass and energy exchange between the planet and the interplanetary space, is an integral part of the planetary multi-layer coupling system. Atmospheres of different compositions and plasmas of different densities and energies exist in planetary space, where mass transportation at different temporal and spatial scales and various energy deposition and dissipation processes occur. Optical remote sensing overcomes the difficulties of capturing global views and distinguishing spatiotemporal variations in in-situ particle and field detections. This chapter introduces the principles and applications of optical remote sensing in planetary science. The first ground-based planetary observatory in China, the Lenghu Observation Center for Planetary Sciences, will be introduced in detail. Future development of optical remote sensing platforms in Chinese planetary exploration program will also be introduced.

Chang’E-4 landed in the South Pole-Aitken (SPA) basin, providing a unique chance to probe the composition of the lunar interior. Its landing site is located on ejecta strips in Von Kármán crater that possibly originate from the neighboring Finsen crater. A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations. In situ spectra of the regolith have peak band positions at 1 and 2 μm, similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper, which confirms that the regolith's composition of the landing area is mostly similar to that of Finsen ejecta. The rock spectrum shows similar band peak positions, but stronger absorptions, suggesting relatively fresh exposure. The rock may consist of 38.1 ± 5.4% low-Ca pyroxene, 13.9 ± 5.1% olivine and 48.0 ± 3.1% plagioclase, referred to as olivine-norite. The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle, but representative of the lunar lower crust. Alternatively, the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials. This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool, indicated by the fine to medium-sized texture (

Controllable synthesis of MoS2 with desired grain morphology via chemical vapor deposition (CVD) or physical vapor deposition (PVD) remains a challenge. Hence, it is important to understand polycry...

Mythimna separata (Walker) moths captured in light traps were monitored in Luohe, central‐northern China, from 1980 to 2016. Annual average temperature recorded an increase of 0.298°C/10 years in this region in the period. Our results indicate that a rising April and May average temperature and earlier occurrences of days recording the highest day temperature (30°C) caused an advanced peak and increasing proportion of high ovarian development levels of first‐generation females in earlier summers. Results using Johnson's formulation of “oogenesis‐flight syndrome” indicate that increasing sexual maturity proportion has resulted in more emigrant individuals in the local first‐generation moth becoming residents, and then increased individuals rapidly in the local second‐generation moth since 2006. Consequences of this action have a boom in corn damage since 2007 in this region. Advanced peak dates of the first and second‐generation moth revealed the same response to increasing average monthly temperatures in the monitoring period. Increasing temperatures, the average May temperature exceeds or equal to 22°C, during the early 2000's may represent a physiological threshold for M. separata development. Our results suggest that climate warming may impact M. separata migratory status and cause a problem of crop production in this region.

Background: Clinical drugs for herpesvirus exhibit high toxicity and suffer from significant drug resistance. The development of new, effective, and safe anti-herpesvirus agents with different mechanisms of action is greatly required. Objective: Novel inhibitors against herpesvirus with different mechanisms of action from that of clinical drugs. Methods: A series of novel 5-(benzylamino)-1H-1,2,3-triazole-4-carboxamides were efficiently synthesized and EC50 values against Human Cytomegalovirus (HCMV), Varicella-Zoster Virus (VZV) and Herpes Simplex Virus (HSV) were evaluated in vitro. Results: Some compounds present antiviral activity. Compounds 5s and 5t are potent against both HCMV and VZV. Compounds 5m, 5n, 5s, and 5t show similar EC50 values against both TK+ and TK− VZV strains. Conclusion: 5-(Benzylamino)-1H-1, 2,3-triazole-4-carboxamides are active against herpesviruses and their activity is remarkably affected by the nature and the position of substituents in the benzene ring. The results indicate that these derivatives are independent of the viral thymidine kinase (TK) for activation, which is indispensable for current drugs. Their mechanisms of action may differ from those of the clinic anti-herpesvirus drugs.

Phosphorene, a monolayer of bulk black phosphorus, is promising for light harvest owing to its high charge mobility and tunable direct band gap covering a broad spectral range of light. Here, via atomic-scale first-principles simulations, we report a ultrahigh activity of hydrogen evolution reaction (HER) of phosphorene originated from defective activation. Quantitative evaluation of the Gibbs free energy of the ad desorption of hydrogen (H) to from phosphorene (delta_GH) reveals that atomic vacancies and edges play a dominant role in activating the reaction. We find that the defective states, empty and well-localized around the defect core, are compensated by H species. This induces a proper hydrogen interaction complying with the thermoneutral condition of the free energy (delta_GH=0) comparable to platinum. Our findings of the highly activating defective states suggest the design of non-metal HER catalysts with structural engineering of earth-abundant phosphorus structures.

The role of India-Eurasian collision and Western-Pacific subduction on the formation of intraplate volcanoes in East Asian is unclear. Wulanhada in North China is a perfect study case for this problem as an intraplate monogenetic volcanic field. We identified 18 volcanoes and 41 vents in Wulanhada volcanic field and divided them into three groups according to notably spatial alignments. Geochemical data show the three groups have similar characteristics in rock classification and trace element patterns. Consequently, the three groups of volcanoes could be treated as one volcanic system. Our K-Ar age data indicate that the volcanism in WVF occurred since the late Miocene and lasted until Quaternary. The feeder fractures far from the W-G fault generally strike ENE-NE, consistent with the maximum principal compressive stress of this region, while the feeder fractures near the W-G fault trend WNW, subparallel to this pre-existing fault. Based on the couplings of stress field and feeder dyke in orientation and timing consistency between the India-Eurasian collision and the volcanism at Wulanhada, the tectonic control from the Tibet Plateau is a dominant factor on the volcanism at WVF. The W-G fault is another indispensable factor for concentration of stress and the distribution of volcanoes at WVF.

An environmentally benign and cost-effective method was designed for isolating and purifying condensed arenes from acetone-extractable portion (AEP) of a high-temperature coal tar through a high pressure preparative chromatograph (HPPC) with different packings, including silica gel, octadecyl silane, octyl bonded silica gel, and diol bonded silica gel. In total, 196 compounds were detected with a gas chromatograph/mass spectrometer from AEP and its eluates. From the eluates, naphthalene, anthracene, phenanthrene, fluoranthene, and pyrene were successfully isolated and purified, and their structures were confirmed by their 1H and 13C nuclear magnetic resonance spectra in addition to their mass spectra. Extraction-HPPC device and solvent recovery process were designed and developed, which can potentially be applied to industrial production because the process is easy-to-operate and ecofriendliness. In addition, the solvents used can be easily recovered and reused, and neither waste water nor other pollutions are emitted.