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Microstructure, thermal conductivity and tensile properties of copper foils are significantly affected by few-layer graphene nanoplates (FLGNPs) as reinforcement embedded into Cu matrix. In the present study, FLGNPs and Cu2+ were co-deposited on the Ti substrate by direct current (DC) electrodeposition to obtain flexible Cu-FLGNPs composites. The texture orientation, phase structure, surface morphology, interface between FLGNPs and Cu matrix of the Cu-FLGNPs composites were characterized. The results show that thermal conductivity and tensile properties of the Cu-FLGNPs composites were increased firstly and then decreased in the process of electrodeposition. Thermal conductivity of the Cu-FLGNPs composites was enhanced from 311 ± 9 W m−1 K−1 characteristic for Cu up to 444 ± 13 W m−1 K−1 when the Gr content was 0.8 g L−1 and the graphene defect density was 6.30×1010 cm−2. Tensile strength of the Cu-0.8FLGNPs composites was 397 MPa, which was improved by 34% compared to the Cu matrix counterparts. Furthermore, the modified thermal model was proposed to evaluate the difference between experimental and theoretical thermal conductivity. The thermal conductivity mechanism was mainly ascribed to graphene defects, electron scattering, phonon scattering and interfacial thermal resistance. The electrodeposition of the Cu-FLGNPs composites provides a feasible route for heat dissipation of electronic and thermal management devices.

MnC2O4 is a promising anode material for high-energy lithium-ion batteries due to its low cost and high capacity. However, the application is limited by the poor cyclic-stability and rate performance due to its low conductivity. Herein, a mesoporous MnC2O4 nanorod/rGO composite is prepared via precipitation followed by a reflux reduction process, where MnC2O4 nanorods are attached to the surface of graphene through electrostatic adsorption. This composite delivers a discharge capacity of 1082, 964, and 808 mAh g−1 after 200 cycles at 3, 5, and 8 C, respectively. The good electrochemical performance can be attributed to the synergistic effect between mesoporous nanorod and rGO, which not only offers high conductivity, nanoparticles, and abundant mesopores to accelerate electrode kinetics but also provides a more stable structure to reduce the volume effect during the charge/discharge process. Therefore, the mesoporous MnC2O4 nanorod/rGO composite could be used as an excellent candidate for its potential application in high-energy lithium-ion batteries.

A novel one-dimensional boron nitride (BN) microtube hierarchical structure was prepared by the chemical vapour deposition method. XRD, SEM, FTIR, Raman, TEM and HR-TEM were used to characterise BN. The samples demonstrated an average inner diameter of 0.6 μm and a tube length of 5-60 μm. Its surface was loaded with a large number of BN nanosheets. The specific surface area of the BN hierarchical structure reached 130.8 m2 g−1, and the structure exhibited good adsorption property for congo red (CR), methylene blue (MB), and copper ions (Cu2+) with maximum uptake capacities of 328.95, 272.48 and 171.23 mg g−1, respectively. The adsorption of these adsorbates onto the BN microtube was well-fitted with the Langmuir model. Moreover, the samples could be recycled by burning or heating in air. Comparative experimental results indicated that the growth mechanism of BN microtubes followed the vapour-liquid-solid model, whereas the growth mechanism of the surface-loaded ultra-thin BN sheets followed the vapour-solid model.

The discovery of dynamic and reversible modifications in RNA expands their functional repertoires. Now, RNA modifications have been viewed as new regulators involved in a variety of biological processes. Among these modifications, thiolation is one kind of special modification in RNA. Several thiouridines have been identified to be present in RNA, and they are essential in the natural growth and metabolism of cells. However, detection of these thiouridines generally is challenging, and few studies could offer the quantitative levels of uridine modifications in RNA, which limits the in-depth elucidation of their functions. Herein, we developed a chemical derivatization in combination with mass spectrometry analysis for the sensitive and simultaneous determination of uridine thiolation and hydroxylation modifications in eukaryotic RNA. The chemical derivatization strategy enables the addition of easily ionizable groups to the uridine thiolation and hydroxylation modifications, leading up to a 339-fold increase in detection sensitivities of these modifications by mass spectrometry analysis. The limits of detection of these uridine modifications can be down to 17 amol. With the established method, we discovered and confirmed that a new modification of 5-hydroxyuridine (ho5U) was widely present in small RNAs of mammalian cells, expanding the diversity of RNA modifications. The developed method shows superior capability in determining low-abundance RNA modifications and may promote identifying new modifications in RNA, which should be valuable in uncovering the unknown functions of RNA modifications.

In this work, a broadband polarization converter in transmission mode based on tri-layered metamaterial structure is proposed to realize asymmetric transmission and linear polarization conversion s...

A unique MoS2/graphene composite (MoS2/GrF) was synthesized via a facile hydrothermal method. XRD, FESEM, EDS, TEM, HRTEM, XPS, and BET analyses were performed to characterize the as-synthesized samples. The samples were demonstrated to present interesting uniform three-dimensional hierarchical heterogeneous structures where MoS2 microspheres (with an average diameter of 750 nm) penetrated the graphene layer. By the “space-confined” effect, the (002) plane of MoS2 is inhibited when grown in the interlayer of GO, which increases the interlayer spacing and improves the rate performance of the electrode. Moreover, MoS2 that grows between the graphene layers can form a good contact, reducing the contact resistance. As an anode material for lithium-ion batteries, the MoS2/GrF electrode exhibited an outstanding reversible capacity (1510 mAh g−1 at 100 mA g−1 after 200 cycles) and excellent rate performance (~990 mAh g−1 at 1000 mA g−1).

Vanadium dioxide (VO2) has unique electrical and optical properties, which have practical applications in many devices. However, preparing high-quality VO2 films and transferring them to flexible substrates by an economic and simple way are still challenging. Functional thin films can be grown on van der Waals (vdW) substrates and then transferred to flexible substrates due to the weak interaction between films and their substrates. Herein, VO2 thin films were grown on mica substrates by using the polymer-assisted deposition technique. By controlling the ion concentration in the polymer precursor solution, a flat seed layer was prepared at the initial growth stage. It was found that the introduction of the seed layer can improve the crystallinity, increase the grain size and reduce the defects of the VO2 thin films. It is believed that less nucleation density and layered growth at the initial growth stage are critical to the formation of large size grains. Our results confirmed that chemical solution deposition can prepared high-quality VO2 films on vdW substrates.

MnC2O4 was prepared via precipitation in N, N-dimethylacetamide –H2O mixed solvents followed by vacuum dehydration process. The structure and morphology can be adjusted by the reaction temperature of the precipitation processes. The precursor MnC2O4·2H2O evolves from the rod-shaped particle with an orthorhombic structure to the plate-like particle with a monoclinic structure when the reaction temperature increases from 60 to 170 °C. After dehydration, the two structures are transformed into orthorhombic β-phase MnC2O4 with similar morphologies to their precursors. Mesoporous MnC2O4 rod can be obtained from the precursor prepared at 100 °C. When used as an anode material for LIBs, this mesoporous MnC2O4 rod delivers a high reversible capacity of 905 and 822 mAh·g−1 after 150 cycles at 2 and 4 A·g−1, respectively, exhibiting good cycle stability and rate performance. The enhanced performance can be attributed to the mesoporous rod-like structure that can improve the structural stability and accelerate the electrode kinetics.

The use of zero-valent iron (ZVI) to enhance anaerobic digestion (AD) systems is widely advocated as it improves methane production and system stability. Accurate modeling of ZVI-based AD reactor is conducive to predicting methane production potential, optimizing operational strategy, and gathering reference information for industrial design in place of time-consuming and laborious tests. In this study, three machine learning (ML) algorithms, namely random forest (RF), extreme gradient boosting (XGBoost), and deep learning (DL), were evaluated for their feasibility of predicting the performance of ZVI-based AD reactors based on the operating parameters collected in 9 published articles. XGBoost demonstrated the highest accuracy in predicting total methane production, with a root mean squared error (RMSE) of 21.09, compared to 26.03 and 27.35 of RF and DL, respectively. The accuracy represented by mean absolute percentage error also showed the same trend, with 14.26%, 15.14% and 17.82% for XGBoost, RF and DL, respectively. Through the feature importance generated by XGBoost, the parameters of total solid of feedstock (TSf), sCOD, ZVI dosage and particle size were identified as the dominant parameters that affect the methane production, with feature importance weights of 0.339, 0.238, 0.158, and 0.116, respectively. The digestion time was further introduced into the above-established model to predict the cumulative methane production. With the expansion of training dataset, DL outperformed XGBoost and RF to show the lowest RMSEs of 11.83 and 5.82 in the control and ZVI-added reactors, respectively. This study demonstrates the potential of using ML algorithms to model ZVI-based AD reactors.

Wind field is a critical issue for radio telescope antenna structure design and observation. As the telescope performance requirements are getting higher and higher, the antenna structure design becomes more and more complicated, and the influence of wind load on antenna pointing in the observation is also serious. How to ensure the stiffness and strength of the structure during the design and to improve the effective observation time during the observation all need accurate wind field data. Due to the traditional wind tower setup method cannot quantitatively evaluate the reliability of the setting point position, so a method based on numerical simulation to optimize the position of the wind tower is proposed. The boundary conditions of numerical simulation are set based on specification parameters, the overall trend is consistent with the measured data, and therefore the simulation accuracy could meet the requirement. Four wind tower positions were set at the test site. According to the simulation results, the root-mean-square error (RMSE) of wind speed between point P2 and the antenna position is the smallest. So, the measured data in P2 could better represent the wind field characteristics of the antenna area.

A 3D hierarchical porous NaTi2(PO4)3/C was successfully synthesized by using choline chloride/triethanolamine-based deep eutectic solvent (DES), which act as both solvent and template. The as-synthesized sample consisted of carbon-coated nanosized NaTi2(PO4)3 with abundant macropores. When this sample is used as an anode material for sodium-ion batteries, it exhibits excellent rate capability (116 mAh g−1 at 5 C and 113 mAh g−1 at 20 C) and superior long-term cyclic stability (capacity retention of over 99% after 1000 cycles at 5 and 20 C). The improved performance can be ascribed to the high Na+ transport and its high structural stability. The excellent electrochemical results indicate that the prepared 3D hierarchical porous NaTi2(PO4)3/C could be used as a promising anode material for SIBs. The finding of this work opens a new way to design porous electrode materials by using DESs as structure-directing reagent.

A high-efficiency tri-band artificial electromagnetic (EM) polarization manipulating metasurface is proposed, which is employing two metal rectangle rings composed of a single-layer reflectance sur...

The rare earth ion Yb3+ doped Bi2WO6 photocatalysts were synthesized by hydrothermal method. Moreover, XRD, XPS, FESEM, TEM, Ramam, N2 adsorption-desorption isotherm measurements and UV-vis diffusion reflectance spectra were used to characterize the Yb3+ doped Bi2WO6 photocatalysts. The morphology, specific surface area, and pore volume distribution were greatly affected after Yb3+ ions doping. Photocatalytic performance of Bi2WO6 was effectively enhanced after Yb3+ ions doping, 6% Yb3+ doped Bi2WO6 had the best photocatalytic performance, and 96.2% Rhodamine B was degradated after irradiated 30 min, which was 1.29 times that of the pristine one. The enhanced photocatalytic performance was due to the increased specific surface area, decreased energy band gap and inhibition of photoelectron-hole recombination after Yb3+ ions doping.

Glasses composed of ternary components (35 – x)Sb2O3–xBi2O3–65P2O5 (0 ⩽ x ⩽ 20 mol%) have been prepared and investigated as a potential alternative to lead-free glass for low temperature applications. Their structural properties were studied by Infrared Spectroscopy IR and Differential Thermal Analysis DTA. Results from the IR showed that Sb3+ and Bi3+ were responsible for glass network structure, which was supported by the diversification of density ρ and molar volume Vm with an increasing amount of Bi2O3. Glass transition temperature Tg, thermal stability, and coefficient of thermal expansion increased after substitution of Bi2O3 for Sb2O3 within the range of 0 mol% to 20 mol%. The water durability decreased and then increased; it could be attributed to the corrosion resistant P–O–Sb bonds. A typical sample of 25Sb2O3–10Bi2O3–65P2O5 possesses excellent properties and can be a promising candidate for further applications.

The spread of antibiotic resistance genes (ARGs) in the environment has aroused growing concern for human health and ecological safety. Recent studies have confirmed that engineered nanomaterials can increase the environmental risk of ARG dissemination mediated by conjugation and transformation. However, whether nanomaterials can mediate the transductive transfer of ARGs by phage infection has not been reported. In this work, the effect of nano-TiO2 on the horizontal transfer of ARGs to E. coli TG1 through transduction by constructed phage gM13 was investigated. Our results showed that nano-TiO2 concentration, particle size, mating time and the ratio of gM13/TG1 could influence the transductive transfer of ARGs. Further studies revealed that nano-TiO2 could promote bacteriophage attachment on cell surfaces, which contributed to gM13 infection. Meanwhile, increasing membrane permeability induced by nano-TiO2 could alleviate transmembrane resistance, which facilitated the infectious entry of phage gM13 into periplasmic space. The expressions of pilus-related genes were improved when E. coli TG1 was exposed to nano-TiO2. Thus, this work is beneficial for gaining a better understanding about the multiple environmental effects of increasingly released nanomaterials and is useful for the control of ARG dissemination in the environment.

In this work, a new orthorhombic organic-inorganic hybrid single crystal (C2H10N2)2MnBr4.2Br with-Zero-dimensional structure was synthesized by slow evaporation method at 75 °C. The crystal structure and intermolecular interactions were performed by single crystal X-ray diffraction and Hirshfeld surface. Optical properties of (C2H10N2)2MnBr4.2Br were systematically studied by Raman, infrared spectrum, UV–vis, photoexcitation spectra, and photoluminescence spectra. The optical band gap (Eg = 2.61 eV) were calculated from the absorption spectra of (C2H10N2)2MnBr4.2Br. This hybrid materials also had shown good thermal stability (decomposition temperature: 288–660 °C). Finally, photoluminescence measurements showed a strong excitation line at 362 nm and a strong fluorescence at 537 nm which makes it a promising material in luminescence field. Keywords: Organic-inorganic materials, Single crystal, Photoluminescence property, Manganese (II) based hybrid compound, Crystal structure

Virus colloidal behavior is governed by the interaction of the viral surface and the surrounding environment. One method to characterize the virus surface charge is the isoelectric point (pI). Traditional determination of virus pI has focused on the bulk characterization of a viral solution. However, virus capsids are extremely heterogeneous, and a single-particle method may give more information on the range of surface charge observed across a population. One method to measure the virus pI is chemical force microscopy (CFM). CFM is a single-particle technique that measures the adhesion force of a functionalized atomic force microscope (AFM) probe and, in this case, a virus covalently bound to a surface. Non-enveloped porcine parvovirus (PPV) and enveloped bovine viral diarrhea virus (BVDV) were used to demonstrate the use of CFM for viral particles with different surface properties. We have validated the CFM to determine the pI of PPV to be 4.8-5.1, which has a known pI value of 5.0 in the literature, and to predict the unknown pI of BVDV to be 4.3-4.5. Bulk measurements, ζ-potential, and aqueous two-phase system (ATPS) cross-partitioning methods were also used to validate the new CFM method for the virus pI. Most methods were in good agreement. CFM can detect the surface charge of viral capsids at a single-particle level and enable the comparison of surface charge between different types of viruses.

MnO is a promising anode material for LIBs due to its low cost and high theoretical capacity, but large volume changes and low conductivity limit its application. To improve its conductivity and electron transport rate, we fabricated mesoporous MnO/C hollow microtube through a hydrodynamic force-induced rapid assembly in T-type microchannel reactor followed with a sintering process. The as-synthesized mesoporous MnO/C hollow microtube is consist of MnO nanograins with abundant porous reaction sites embedding uniformly on carbon layers to form a hollow tubular-like structure. When used this mesoporous MnO/C hollow microtube as an anode material of LIBs, it can deliver a high reversible capacity of 845 mAh·g−1 after 100 cycles at 1.5 A g−1 and a capacity of 699 mAh·g−1 at 3.75 A g−1, exhibiting good rate capability and cycle stability. The temperature-dependence electrochemical impedance spectra showed that the mesoporous hollow microtube structure can decrease the barrier energy for jumping through the SEI film, the intercalation reaction and the diffusion of Li+ in the bulk of the solid. The improved performances can be attributed to the unique mesoporous hollow-tubular structure, which enhances the structural stability, improves the electrical conductivity and fasten electrode reaction kinetics.

Ferritic spheroidal graphite irons with nodularity from 72% to 96% were prepared. The relationship between the nodularity and the mechanical properties of the ferritic spheroidal graphite iron was investigated. The effect of nodularity on the mechanical properties and tensile fracture of the cast iron were studied. Results showed that the tensile strength Rm, yield strength Rp0.2, elongation to failure A5, and impact energy KV2 of the cast iron had a good linear relationship with its nodularity. Nodularity and annealing treatment would obviously affect the fracture characteristics of ferritic spheroidal graphite iron. The annealed ferritic spheroidal graphite iron with 93% nodularity showed a completely ductile rupture. With the decrease of nodularity from 93% to 72%, the cleavage fracture area ratio increased gradually from 0% to 8.3%. Compared with as-cast ferritic spheroidal graphite iron, annealing treatment reduced the cleavage fracture area of the ferritic spheroidal graphite iron.

To solve problems in small-scale and complex structural traps, the inverse Gaussian-beam stack-imaging method is commonly used to process crosswell seismic wave reflection data. Owing to limited coverage, the imaging quality of conventional ray-based crosswell seismic stack imaging is poor in complex areas; moreover, the imaging range is small and with sever interference because of the arc phenomenon in seismic migration. Thus, we propose the inverse Gaussian-beam stack imaging, in which Gaussian weight functions of rays contributing to the geophones energy are calculated and used to decompose the seismic wavefield. This effectively enlarges the coverage of the reflection points and improves the transverse resolution. Compared with the traditional VSP-CDP stack imaging, the proposed methods extends the imaging range, yields higher horizontal resolution, and is more adaptable to complex geological structures. The method is applied to model a complex structure in the K-area. The results suggest that the wave group of the target layer is clearer, the resolution is higher, and the main frequency of the crosswell seismic section is higher than that in surface seismic exploration The effectiveness and robustness of the method are verified by theoretical model and practical data.

Design and synthesis of non-noble metal electrocatalysts with high activity and durability for the electrolysis of water is of great significance for energy conversion and storage. In this work, we prepared a series of Fe-doped MoS2 nanomaterials by simple one-pot solvothermal reactions of (NH4)2MoS4 with FeCl3·6H2O. An optimized working electrode of Fe-MoS2-5 displayed high hydrogen evolution reaction (HER) activity with a relatively small overpotential of 173 mV to achieve a current density of 10 mA cm-2 in 0.5 M H2SO4, along with no significant change in catalytic performance even after 1000 cyclic voltammetry (CV) cycles. Fe-MoS2 nanoparticles on nickel foam (NF; denoted as Fe-MoS2/NF) exhibited an overpotential of 230 mV at 20 mA cm-2 for the oxygen evolution reaction (OER) and 153 mV at 10 mA cm-2 for the HER in 1.0 M KOH electrolyte. Fe-MoS2/NF was stable for more than 140 h under these conditions. Furthermore, the two electrode system of Fe-MoS2/NF (anode)//Fe-MoS2/NF (cathode) electrodes demonstrated excellent electrocatalytic activity toward overall water splitting with a low potential of 1.52 V at 10 mA cm-2 in 1.0 M KOH electrolyte.

The plasma electrolytic oxidation (PEO) with coating thickness of ~10 μm and ~35 μm on 7A85 aluminum alloy was performed using the alkaline silicate based electrolyte, and the corresponding influence on fatigue behavior in air and 3.5% NaCl solution was studied. Results show that PEO treatments reduced the corrosion fatigue life of 7A85 aluminum alloy. The corrosion fatigue life of samples with thin PEO coatings (10 μm-thick) is decreased for the occluded battery promoted localized corrosion, while that of samples with thicker PEO coatings (35 μm-thick) is reduced for the low ductility of the oxide coating. The shot peening (SP) treatment with ceramic shots was introduced as pretreatment of PEO, The surface residual stresses as well as the residual stress of the substrate beneath the coating were analyzed by X-ray stress analyzer. The corrosion fatigue performance of shot peening combined PEO treated samples is improved for the residual compressive stress field induced by shot peening. Whereas, enhanced notch effect was induced by shot peeing surface roughening and oxide coating local overgrowth, so the corrosion fatigue life of samples with SP, surface polishing, PEO, respectively is further improved for the reduction of notch effect.

Herein, γ-AlO(OH) as an inorganic was successfully inserted into MgAl-LDH layer by a one-pot synthesis, the composite as an adsorbent for removing methyl orange (MO) from wastewater. The structure and adsorption performance of γ-AlO(OH)/MgAl-LDH were characterized. The research shows that the expansion (003) plane and the hydroxyl active site of γ-AlO(OH)/MgAl-LDH can promote adsorption capacity and adsorption kinetics, respectively. Therefore, γ-AlO(OH)/MgAl-LDH exhibits a super adsorption performance, which completely adsorbs MO at the concentration of 1000 mg g−1. In addition, the maximum adsorption capacity of MO was 4681.40 mg g−1 according to the Langmuir model. These results indicate that γ-AlO(OH)/MgAl-LDH is a potential adsorbent for the removal of organic dyes in water.

In lithium-oxygen batteries, the solubility of LiO2 intermediates in the electrolyte regulates the formation routes of the Li2O2 discharge product. High-donor-number electrolytes with a high solubility of LiO2 tend to promote the formation of Li2O2 large particles following the solution route, which eventually benefits the cell capacity and cycle life. Here, we propose that facet engineering of cathode catalysts could be another direction in tuning the formation routes of Li2O2. In this work, β-MnO2 crystals with high occupancies of {111} or {100} facets were adopted as cathode catalysts in Li-O2 batteries with a tetra(ethylene)glycol dimethyl ether electrolyte. The {111}-dominated β-MnO2 catalyzed the formation of the Li2O2 discharge product into large toroids following the solution routes, while {100}-dominated β-MnO2 facilitated the formation of Li2O2 thin films through the surface routes. Further computational studies indicate that the different formation routes of Li2O2 could be related to different adsorption energies of LiO2 on the two facets of β-MnO2. Our results demonstrate that facet engineering of cathode catalysts could be a new way to tune the formation route of Li2O2 in a low-donor-number electrolyte. We anticipate that this new finding would offer more choices for the design of lithium-oxygen batteries with high capacities and ultimately a long cycle life.

Ulcerative colitis (UC) has been listed as one of the refractory diseases of modern society by the World Health Organization. Our previous studies found that Turkish galls Gallotannins (TGTs) have a significant effect on anti-UC. Here, TGTs were extracted using a simple method and TGTs-FeIII microcapsules were prepared by a self-assembly technique. Microcapsules were characterized by liquid chromatography-mass spectrometry, scanning electron microscopy, and so forth. The results verified that hollow spheres of TGTs-FeIII microcapsules were successfully prepared. It is interesting that microcapsules were more likely to accumulate on the inflammatory surface from ex vivo and in vivo adhesion experiments, and effectively alleviate UC symptoms. This study will provide valuable insight into the development of safe and efficient drug delivery system platforms for further biomedical usages.

A new Zn(II)-based coordination complex, [Zn(L)2]·(CH3OH)0.5·(H2O)2 (1) (L = 3-chloro-6-(3-methyl-5-phenyl-1H-pyrazol-1-yl) picolinic acid) has been synthesized by solvothermal condition. The uncoordinated oxygen atoms in the compound can be used as active sites for post-synthetic modifications. Therefore, compound 1 can act as a precursor material for coating lanthanides. The Ln@1 (Tb@1 and Eu@1) materials showed characteristic emission properties of Ln3+ ions. These emissions are selectively quenched by nitroaromatic compounds in ethanol with good sensitivity. The result illustrated that the materials selectively detect of 2,4,6-trinitrophenol (TNP), 2,4-dinitroaniline (2,4-NA) with higher efficiency (Ksv>104 M−1) compared with other nitroaromatic compounds, including 2,4-dinitrotoluene (2,4-DNT), 2,6-dinitrotoluene (2,6-DNT), nitrobenzene (NB), 4-nitrophenol (4-NP), 4-nitrotoluene (4-NT). Furthermore, the fluorescent paper strips were prepared in order to make them as portable sensing agents. In addition, a probable sensing mechanism was also discussed in this paper.

Developing high-performance overall water-splitting electrocatalysts working under alkaline condition is highly desirable but many challenges remain. Herein, the in-situ surface-derivation of Ni-Mo bimetal sulfides nanosheets on Co3O4 nanoarrays, which supported on carbon fibers (Ni-Mo-S@Co3O4/CF) was designed and constructed. The as-prepared hybrid catalyst exhibits excellent electrocatalytic performance for both OER and HER under alkaline conditions, with only a small overpotential of 275 mV and 85 mV at a current density of 10 mA cm−2, respectively. Furthermore, the hybrid catalysts assembled full electrolyzer achieved a current density of 10 mA cm−2 at 1.57 V in an alkaline condition, without decay even after a durability test of 50 h. These results demonstrate that in-situ surface-derivation is a promising strategy for the design of efficient overall water splitting catalysts.

During the development and construction of the Puguang Gas Field, Sichuan Basin, an advanced automatic control system and a fully covered industrial Internet of Things were built. In order to further increase its development benefit, the Puguang Gas Field started the construction of an intelligent gas-field project in 2013. However, there are not mature models and construction standards of intelligent oil and gas fields at home and abroad for reference. In this paper, an overall architecture design of intelligent gas field and its technical and business architecture design were demonstrated according to the principle of “overall planning, step-by-step implementation, response in each step and stressing the main points”, and based on the mainstream design concept and practical experience of intelligentization. Then, combined with the key business target and implementation principle of the gas field, it was conducted and applied. And the following research results were obtained. First, the overall architecture of the intelligent gas field project includes a platform, two centers and two systems, i.e., integrated coordinated application platform, resource sharing center, intelligently assistant decision-making direction center, standard specification system and information safety system. Second, the technical architecture consists of four layers, i.e., industrial Internet of Things + equipment perception introducing layer, infrastructure cloud service layer, platform cloud service layer and software cloud service layer. Third, the business architecture is designed focusing on four support units, including exploration and development management of the gas field, production and emergency direction management of gas field, QHSE management of gas field and business management of the gas field. Fourth, the construction of the intelligent gas field project creates four abilities, i.e., assistant exploration and development decision-marking ability, production optimization and coordination ability, safety control and treatment ability and refined business management ability, to support the smooth operation, efficient management and safe production of the Puguang Gas Field. In conclusion, the intelligent management and decision-making system with the resource sharing center as the base, the integrated platform as the core and two systems as the guarantee has been preliminarily built in the Puguang Gas Field. Keywords: Intelligent gas field, Puguang gas field, Architecture design, Internet of things, Big data, Cloud technology, Assistant decision-making

The organic–inorganic hybrid compound (C6H9N2)2ZnI4 was prepared by the slow evaporation method at room temperature. The single crystal X-ray diffraction results indicated that the (C6H9N2)2ZnI4 crystal was a monoclinic system with the space group P21/c at room temperature. The compound displayed typical Zero-dimensional (0D) consists of two [C6H9N2]+ cation and one anionic tetrahedral [ZnI4]2−. The sample presented relatively perfect thermal stability up to 260 °C and wide band gap about 3.33 eV which was consistent with the theoretical value. Furthermore, the electrical properties were characterized by impedance spectroscopy with the 209 Hz–5 MHz frequency from 308.15 K to 333.15 K. The alternating current (AC) conductivity of the compound was discussed using Jonscher’s law: σ f = σ dc + A f s and the conduction could be attributed to the correlated barrier hopping (CBH) model. Therefore, this kind of organic–inorganic hybrid compound will be a promising candidate for optical and electronic applications.

The preparation of TEM samples using focused-ion beam (FIB) techniques allows for characterization of electron-transparent site-specific areas, such as oxide-metal interfaces and crack tips, leading to improved understanding of material degradation mechanisms. Using conventional FIB techniques to prepare zirconium alloy TEM samples results in the production of artefact δ hydrides during the final thinning stage, which can confound analyses and mechanistic interpretation, especially when understanding hydride morphology and crystallography is critical. A comparison of various preparation methods was performed to determine their influence on artefact hydrides in TEM samples. As-received Zircaloy-4 material with

Nano-indentation analysis was employed to investigate the mechanical response of heavy ion irradiated X-750 Ni-based superalloy in both solution-treated (ST) and precipitation-hardened (PH) conditions. Helium pre-implantation was carried out at 300 °C up to 5000 appm followed by Ni+-ion irradiation up to 1 dpa at room temperature or 400 °C. Cross-sectional TEM examination was used to characterize the microstructural evolution of the irradiated material and correlate this with nano-scale mechanical test results. Nano-hardness measurements after irradiation at 400 °C showed a similar trend of irradiation-induced hardening, for both ST and PH materials. In contrast, radiation at room temperature resulted in different mechanical responses, with hardening in the ST condition compared to softening in PH. The hardening behaviour was attributed to the creation of irradiation-induced defects including, cavities, Frank loops and small defect clusters; whereas, the γ′-precipitate instability (disordering/dissolution) in PH material resulted in the observed softening. The individual and combined contribution of each type of defects under irradiation hardening were estimated by employing three different obstacle models; results were verified by nano-indentation data for both ST and PH materials. In addition, the softening of the irradiated PH material which results from disordering and dissolution was separately calculated, allowing an estimate of the total yield strength change. TEM analysis of post-indentation microstructure revealed that un-irradiated X-750 deformed by homogenous dislocation motion; however, localized deformation in the form of nano-twins was the dominant deformation mechanism in irradiated X-750.

Aiming at efficiently and precisely describing and predicting the rate-independent nonlinear hysteresis characteristics of magnetorheological (MR) dampers, this paper investigates a resistor-capacitor (RC) operator-based hysteresis model for MR dampers. The model is under the frame of the “restructured model” proposed by Bai et al. (“Principle and validation of modified hysteretic models for magnetorheological dampers,” Smart Materials and Structures, 24(8), 085014, 2015) with the RC operator substituting the Bouc-Wen operator. The essence of the RC operator is the theoretical generalization of the hysteresis phenomenon that the RC circuit presents in charging and discharging processes. In detail, a virtual displacement variable and updating laws for reference points are employed. The virtual displacement keeps positive in uploading (i.e., RC circuit in charging process) while negative in downloading (i.e., RC circuit in discharging process). The hysteresis output is achieved through applying algebraic expressions, which realizes the RC operator. Based on the experimental results of a MR damper, the comparison and analysis of the RC operator-based model and the Bouc-Wen operator-based hysteresis models, including the Bouc-Wen model and the restructured model, are conducted.

A fluorescent sensor L based on a pyrazolopyrimidine core simultaneously detects Cu2+ and Ni2+ ions by photoluminescence quenching, even in the presence of other metal cations. Sensor L possesses high association constants of 5.24 × 103 M−1 and 2.85 × 104 M−1 and low detection limits of 0.043 μM and 0.038 μM for Cu2+ and Ni2+, respectively. The binding stoichiometry ratios of L to Cu2+ or Ni2+ is 1:1 as determined by Benesi-Hildebrand and Job's plots, and by crystal structures. DFT calculations on L-Cu2+ indicated reduced electron donation from the coordinated pyrazolopyridine to the fused pyrimidine and pendant phenyl group which, together with a smaller HOMO-LUMO orbital gap could favour non-radiative decay and explain the observed fluorescence quenching. Sensor L possessed low cytotoxicity and good imaging characteristics for Cu2+ and Ni2+ in living cells, suggesting potential applications for detecting Cu2+ and Ni2+ in vivo.

A new photocatalyst, few-layer MoS2 grown in MgAl-LDH interlayers (MoS2/MgAl-LDH), was prepared by a facile two-step hydrothermal synthesis. The structural and photocatalytic properties of the obtained material were characterized by several techniques including powder X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and UV-vis absorption spectroscopy. The MoS2/MgAl-LDH composite showed excellent photocatalytic performance for methyl orange (MO) degradation at low concentrations (50 mg L−1 and 100 mg L−1). Furthermore, even for a MO solution concentration as high as 200 mg L−1, this composite also presented high degradation efficiency (>84%) and mineralization efficiency (>73%) at 120 min. The results show that the MoS2/MgAl-LDH composite has great potential for application in wastewater treatment.

Puerariae Radix (PR) and Gastrodiae Rhizome (GR) is frequently used in traditional herbal formulas to treat cardio-cerebral vascular diseases due to their synergistic effects. In this study, to elucidate the action mechanism of PR-GR in vivo, a simple and reliable ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for simultaneous determination of nine bioactive ingredients from PR-GR in plasma was developed and applied to a comparative pharmacokinetic study following oral administration of PR, GR, and PR-GR aqueous extracts in rats. The effect of GR on the absorption of components of PR was also investigated by single-pass intestinal perfusion study. Results showed that comparing to the single herbs, PR-GR extract significantly increased the systemic exposure of puerarin, 3'-hydroxypuerarin, 3'-methoxypuerarin, 6″-O-xylosylpuerarin, daidzin, genistein, and gastrodin. Moreover, the intestinal absorption of puerarin and daidzin could be improved by GR extract and inhibitors of P-glycoprotein and multidrug resistanceassociated protein 2, respectively. These results indicate that the combination of PR and GR increases the levels of their bioactive ingredients exposed in the blood, and GR increases the absorption of ingredients of PR may by inhibition of the efflux mediated by P-glycoprotein and multidrug resistanceassociated protein 2. This is the first report for the pharmacokinetics and intestinal absorption of PR-GR, which may explain their synergetic effects in the treatment of circulatory systematic diseases and provide a meaningful insight for their clinical applications.

Oxide dispersion strengthened (ODS) steels of Fe–9Cr–xAl (x = 0.4, 2.5, 4.5 and 8.0 wt%) have been fabricated by mechanical alloying, hot isostatic pressing and subsequent forging. Both the ferrite matrix and yttria particles were coarsened by the addition of Al. However, a bimodal structure consisting of coarse grains closely surrounded by fine grains is formed, and develops with increasing Al addition. Moreover, at the same time, nano-sized alumina particles precipitate in the interior of the bimodal ferrite grains. The tensile strength increases gradually with Al addition due to back stress strengthening combined with Orowan strengthening. The formation mechanism of the bimodal structure and intragranular precipitation of the Al added ODS steels were also discussed.

Recent years, many scientists address the research on text sentiment analysis of social media due to the exponential growth of social multimedia content. Natural language ambiguities and indirect sentiments within the social media text have made it hard to classify by using traditional machine learning approaches, such as support vector machines, naive Bayes, hybrid models and so on. This article aims to investigate the sentiment analysis of social media Chinese text by combining Bidirectional Long-Short Term Memory (BiLSTM) networks with a Multi-head Attention (MHAT) mechanism in order to overcome the deficiency of Sentiment Analysis that is performed with traditional machine learning. BiLSTM networks, not only solve the long-term dependency problem, but they also capture the actual context of the text. Due to the fact that the MHAT mechanism can learn the relevant information from a different representation subspace by using multiple distributed calculations, the purpose is to add influence weights to the constructed text sequence. The results of the numerical experiments show that the proposed model achieves better performance than the existing well-established methods.

A series of noble-metal-free NiS2-loaded g-C3N4 hybrid composites were prepared via simple hydrothermal method. Benefited from the wider spectral response range and the effective separation of photoelectron-holes of g-C3N4-NiS2 heterojunction catalysts, as well as the rich unsaturated active S atoms on the NiS2 with S22−, the composite catalysts has prominent photocatalytic performance for H2 evolution. Remarkably, the optimal composite photocatalysts achieved an average hydrogen production rate as high as 715.83 μmol/h/g in 3 h under visible-light irradiation, which is 2.75 times as high as that of precious metal Pt (259.5 μmol/h/g) as a co-catalyst. Besides, the composite catalyst still shows prominent photocatalytic performance for H2 evolution after three continuous photocatalytic reaction cycles for 9 h. This study provided a facile method to build a low-cost but effective metal sulfide co-catalyst for hydrogen production under visible light irradiation.

The effect of heavy ion or neutron irradiation on the plasticity of Zr-2.5Nb pressure tube alloy is investigated by a combination of nanoindentation and numerical modeling, with indentation tests along the tube axial (AD) and transverse directions (TD). The true stress-strain curves are calculated from nanoindentation load-displacement curves based on an analytical model. The work hardening behaviors of samples loaded in different orientations are compared before and after irradiation. Heavy ion irradiation up to 1.2 × 1015 ion/cm2 significantly increases the hardness of both AD and TD samples. The analytical model can precisely capture the plastic properties of both unirradiated and irradiated material. The calculated true stress-strain curves, including elasticity, yield strengths, and work hardening behaviors of unirradiated and irradiated samples show reasonably good agreement with experimental stress-strain curves derived from uniaxial tensile tests. The change of work hardening exponent due to irradiation shows strong orientation dependency; it decreases from 0.22 to 0.11 in AD but stays almost the same at ∼0.09 in TD after ion irradiation. The work hardening exponent is about 0.16 and 0.08 for neutron irradiation AD and TD samples, respectively. These orientational differences are related to the anisotropic interactions between plastic-flow dislocations and irradiation induced prismatic dislocation loops.

In this paper, 40 MeV Zr ion irradiation of Zr-2.5Nb pressure tube alloy was carried out, delivering a damage layer 6.5 μm deep. Uniaxial micropillar compression experiments along the tube axial (AD) and transverse directions (TD) were conducted. Irradiation was found to alter the deformation mechanisms and to increase the yield strength more in the AD oriented pillars than TD pillars for irradiation up to 0.6 dpa. This anisotropy in response is discussed in terms of the limitations of the micropillar compression method and the different deformation mechanisms which are activated in each orientation. The anisotropic hardening effect of -type dislocation loops on prismatic , basal , and pyramidal slip systems is also discussed. The micropillar compression results were also compared with nanoindentation results conducted on the same material.

Manganese oxalates with different structures and morphologies were prepared by the precipitation method in a mixture of dimethyl sulfoxide (DMSO) and proton solvents. The proton solvents play a key role in determining the structures and morphologies of manganese oxalate. Monoclinic MnC2O4·2H2O microrods are prepared in H2O-DMSO, while MnC2O4·H2O nanorods and nanosheets with low crystallinity are synthesized in ethylene glycol-DMSO and ethanol-DMSO, respectively. The corresponding dehydrated products are mesoporous MnC2O4 microrods, nanorods, and nanosheets, respectively. When used as anode material for Li-ion batteries, mesoporous MnC2O4 microrods, nanorods, and nanosheets deliver a capacity of 800, 838, and 548 mA h g−1 after 120 cycles at 8C, respectively. Even when charged/discharged at 20C, mesoporous MnC2O4 nanorods still provide a reversible capacity of 647 mA h g−1 after 600 cycles, exhibiting better rater performance and cycling stability. The electrochemical performance is greatly influenced by the synergistic effect of surface area, morphology, and size. Therefore, the mesoporous MnC2O4 nanorods are a promising anode material for Li-ion batteries due to their good cycle stability and rate performance.

Polar phosphorylated metabolites are involved in a variety of biological processes and play vital roles in energetic metabolism, cofactor regeneration, and nucleic acid synthesis. However, it is often challenging to interrogate polar phosphorylated metabolites and compounds from biological samples. Liquid chromatography-mass spectrometry (LC/MS) now plays a central role in metabolomic studies. However, LC/MS-based approaches have been hampered by the issues of the low ionization efficiencies, low in vivo concentrations, and less chemical stability of polar phosphorylated metabolites. In this work, we synthesized paired reagents of light and heavy isotopomers, 2-(diazomethyl)phenyl)(9-methyl-1,3,4,9-tetrahydro-2H-pyrido[3,4-b]indol-2-yl)methanone (DMPI) and d3-(2-(diazomethyl)phenyl)(9-methyl-1,3,4,9-tetrahydro-2H-pyrido[3,4-b]indol-2-yl)methanone (d3-DMPI). The paired reagents of DMPI and d3-DMPI carry diazo groups that can efficiently and selectively react with the phosphate group on polar phosphorylated metabolites under mild conditions. As a proof of concept, we found that the transfer of the indole heterocycle group from DMPI/d3-DMPI to ribonucleotides led to the significant increase of ionization efficiencies of ribonucleotides during LC/MS analysis. The detection sensitivities of these ribonucleotides increased by 25-1137-fold upon DMPI tagging with the limits of detection (LODs) being between 7 and 150 amol. With the developed method, we achieved the determination of all the 12 ribonucleotides from a single mammalian cell and from a single stamen of Arabidopsis thaliana. The method provides a valuable tool to investigate the dynamic changes of polar phosphorylated metabolites in a single cell under particular conditions.

Ba 0.5 Sr 0.5 TiO 3 /Ba 0.5 Sr 0.5 Ti 1.02 O 3 two-layer thin films are fabricated on Pt/Ti/SiO 2 /LiNbO 3 (LNO) substrates by using RF sputtering. Both structure and electrical performance have been investigated. The films with parallel structure are characterized by two electronic devices, such as X-ray diffraction (XRD) and scanning electron microscope (SEM). The capacitance and dielectric constant of the two-layer films are 0.91nF and 1310 respectively, which are measured by using an LCR meter. With a DC bias field of 237KV/cm applied on the BST films, a tunability of 41% are obtained. The ratio of tunability to electric field has been increased by 34%, which is paramount for low-power electronics applications.

Superhydrophobic coatings can offer promising protection for metals against harsh service conditions. However, real applications are facing great challenges with the focus problem of lacking mechanical robustness. Current methods addressing this issue can not completely solve the problem or is not unsuitable for large-scale applications. Here, we propose an innovative strategy to fabricate a bioinspired superhydrophobic coating on 6061 Al via a simple and high-output route. By creating a mosquito-eye-like nanoframework-nanofiller structure with two different length scales, the coating is equipped with superhydrophobic property and excellent mechanical robustness, which are usually considered as two mutually exclusive properties. Based on a modified Cassie-Baxter model and a Gibbs interfacial energy model, a wetting theory is established to analyze the observed nonlinear change of the water contact angle, which suggests that the coating initially remains in the heterogeneous wetting state and abruptly transits to the intermediate wetting state. The theory further predicts the loss of anti-icing property upon abrasion, which is also confirmed by experiments. The superhydrophobic coating with robustness against abrasion will find its potential application values in complex service conditions.

Overuse of antibiotics in animal husbandry has led to an increase of antibiotic resistance microorganisms as well as antibiotic-resistance genes (ARGs). Duck farming in China is practiced on a large and diverse scale and the overuse of antibiotics in this field is gaining attention recently. We evaluated the diversity of ARGs from five duck farms using a functional metagenomic approach and constructed five libraries. A total of seventy-six resistant determinants were identified, of which sixty-one were gene variants or novel genes. The novel genes contained five β-lactamase-encoding genes designated as blaDWA1, blaDWA2, blaDWA3, blaDWA4 and blaDWB1, respectively, and two genes conferring resistance to fosfomycin designated as fosA-like1 and fosA-like2. Three of the five β-lactamase-encoding genes were further identified as extended-spectrum β-lactamases (ESBL) that can hydrolyze both penicillins and cephalosporins. Besides, two of the five β-lactamase-encoding genes were associated with mobile genetic elements, indicating a high potential for transfer of the genes to other bacterial hosts. The two novel fosA-like genes were able to increase the MICs of the test Escherichia coli strain from 2 μg/mL to as high as 256 μg/mL(up to 128-fold increase). Our study provides a reference for ARGs prevalence in duck farm wastes and implies that they are an important resistome reservoir, especially for novel ARGs with high spread potential.

Two sets of hybrid constructed wetlands (HCWs) with the first-stage aeration were used to treat actual domestic sewage in this paper, where the effects of three important factors of aeration mode, hydraulic loading rates (HLR), and aeration volume on the removal of pollutants in both HCWs were studied in contrasts. In addition, the pollutant removal efficiency, the contribution of plants, and the characteristics of biofilm in both HCWs were explored. The results of 250-day experiment showed that the TN removal capacity of HCW combining vertical flow CW with horizontal flow CW (VF-HF) was better than HCW’s converse combination (HF-VF) in treatingsewage, while the removal efficiency of COD and NH4+-N were similar, and the concentrations of TN and COD in the effluent of VF-HF could successfully meet the National discharge requirements. Compared with the continuous aeration, the intermittent aeration only had a little effect on the removal of COD and NH4+-N, but could improve TN removal performance in both HCWs. Meanwhile, increasing the aeration volume was beneficial to remove NH4+-N but not TN in HCWs. In addition, although the pollutant removal performances in both HCWs were impacted, the removal capacity of TN in VF-HF was only affected a little, when HLR was increased by 50%. The contribution of plants’ uptake accounted for about 10% to nitrogen removal and 20% to phosphorus removal in both HCWs. The biomass at the filler surface near the plant rhizosphere was greater than that in the non-rhizosphere zones, and the impact of plant rhizosphere on the nitrification activity of biofilm was significantly greater than that on denitrification activity in both HCWs.

The development of metal–organic frameworks (MOFs) as high-efficiency electrocatalysts for water splitting has attracted special attention due to their unique structural features including high porosity, large surface areas, high concentrations of active sites, uniform pore sizes and shapes, etc. Most of the related reports focus on the in situ generation of high-efficiency electrocatalysts by annealed MOFs. However, the pyrolysis process usually destroys the porous structure of MOFs and reduces the number of active sites due to the absence of organic ligands and agglomeration of metal centers. In this work, we prepared unique NiCo-MOF hollow nanospheres (NiCo-MOF HNSs) by a solvothermal method and further fabricated Fe-doped NiCo-MOF HNSs (Fe@NiCo-MOF HNSs) by a simple impregnation-drying method. Significant enhancement of electrocatalytic activity of Fe@NiCo-MOF HNSs was witnessed because of the doped Fe. Compared with the parent NiCo-MOF HNSs, the optimized Fe@NiCo-MOF HNSs exhibited a lower overpotential of 244 mV at 10 mA·cm−2 with a smaller Tafel slope of 48.61 mV·dec−1, which was lowered by ca. 90 mV due to the influence of Fe doping on the electronic structure of the active centers of Ni and Co. The above materials also displayed excellent stability without obvious activity decay for at least 16 hours. These findings present a new entry in the design and fabrication of high-efficiency MOF-based electrocatalysts for energy conversion.

Circular RNAs (circRNAs) are a class of noncoding RNAs (ncRNAs) that lack a 5' end cap or a 3' end poly-(A) tail and form a circular structure through covalent bonds. Compared to linear RNAs, circRNAs are more conservative and stable, and their distribution is spatiotemporally regulated. circRNAs, as a new type of competitive endogenous RNA (ceRNA), are involved in many disease processes and are also related to the occurrence and development of tumors. Over the past three years, the role of circRNAs in hematological malignancies has received increasing attention. Related research has shown that circRNAs may regulate the occurrence and development of hematological malignancies and contribute to drug resistance through a variety of molecular mechanisms. Therefore, to lay the foundation and point out directions for further research on circRNAs, this article systematically reviews the research progress on circRNAs in leukemia, lymphoma, and myeloma.

Pristine metal-organic frameworks (MOFs) have received much attention in recent years due to their high specific surface areas, large porosity, excellent pore size distributions, flexible structure, and remarkable catalytic properties. The design of functional MOFs that can function as efficient HER and OER catalysts is significant in solving the energy crisis but remains a big challenge. Tri-metallic metal-organic frameworks show a good application prospect in water oxidation. In this review, we are going to focus on the latest progress and future trends in the development of pristine trimetallic MOFs with respect to the OER. The synergistic effect between multi-metal active sites is effective at improving the intrinsic activity of MOFs toward the OER. By summarizing the synthesis method of tri-metallic MOFs and observing their performance toward the oxygen evolution reaction, we hope that this review will trigger new developments in coordination chemistry, electrochemistry, nanomaterials and energy materials.