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The change in the fracture microstructure of loaded coal affects the gas seepage characteristics of the coal. Using micron CT scanning (μ-CT) and nuclear magnetic resonance (NMR) experiments, the fractal characteristics of coal fracture structure under triaxial compression are studied from two aspects of theoretical and experimental fractal dimension for the first time. VG Studio MAX software was used to reconstruct the three-dimensional (3D) fracture structure of the coal samples, and the 3D fracture structure was modified by the porosity measured by NMR. Through the analysis of the reconstruction model and the T2 relaxation spectrum, the spatial distribution of internal cracks in coal was obtained. The fractal geometry theory, NMR experimental fractal dimension algorithm and 3D box counting method were used to calculate the theoretical and experimental fractal dimensions and then comprehensively analyze the fractal characteristics of cracks in loaded coal. The results show that an external load promotes the development of pores/cracks in coal. With increasing theoretical fractal dimension, CT porosity increases from 0.0630% to 0.101%, and NMR porosity increases from 0.0655% to 0.105%. The relationship between porosity and theoretical fractal dimension can be expressed by y = ax2+ bx+c (fractal dimension is an independent variable). With increasing porosity, the experimental fractal dimension of NMR decreases linearly from 2.975 to 2.951, and the experimental fractal dimension of μ-CT increases linearly from 2.191 to 2.324. The different changing trends of theoretical and experimental fractal dimensions verify the differences in their representational meanings. [ABSTRACT FROM AUTHOR]

Predrainage of gas by cross‐boreholes is an important method to prevent coal and gas outbursts in the process of a coal roadway excavation. Limitations of technologies and poor effects of preventing coal and gas outbursts occur in the coal seam with a soft layer. In this study, a new hydraulic caving technology for cross‐boreholes has been proposed to solve this problem. A CT equipment was used to observe the development of coal fissures around cross‐boreholes in the coal seam with a soft layer. The plastic zone range and permeability distribution of ordinary hydraulic slotting technologies and the new hydraulic caving technology also were compared by numerical simulation. The field test of hydraulic caving was taken in the Xuehu Mine (China). The results show that the fracture development degree of soft coal is greater than that of hard coal at the same distance from cross‐boreholes. The fracture development degree in the plastic zone is greater than that in the elastic zone. The hydraulic caving technique can achieve the same effect as the ordinary hydraulic slotting with less workload. The mass of coal discharged from a cross‐borehole was 1.15 t/m and the average methane concentration of single drainage borehole increased by 1.09‐4.1 times, and the average methane extraction amount of single drainage borehole increased by 6.06 times. Elimination of coal and gas outburst had been completed after 110 days of extraction in the area of hydraulic caving, and Q and S values are lower than the critical value during roadway excavation. It is conclusion that hydraulic caving technique can effectively improve the permeability and rapidly eliminate coal and gas outburst in the coal seam with a soft layer. [ABSTRACT FROM AUTHOR]

Magnetic fields vertical to electric fields were applied during electrodeposition process to prepare CoNiMn magnetic thin films. Influences of different magnetic intensities on electrochemistry mechanism, nucleation, surface morphology and magnetic property of CoNiMn films were studied. Magnetohydrodynamics phenomenon caused by Lorentz forces during magnetic electrodeposition process tends to agitate the diffusion layer near cathode. It was found out that, CoNiMn films fabricated by magnetic electrodeposition process belonged to a kind of typical progressive nucleation mechanism. Anomalous codeposition phenomenon of CoNi was affected by magnetic fields. Higher magnetic intensity tended to obtain smooth surface of CoNiMn films with smaller and denser particles. Coercivity and remanence of CoNiMn alloy films increased sharply when magnetic field was induced. Magnetic property of vertical direction was better than parallel direction, which indicated that CoNiMn magnetic film possessed good vertical anisotropy. [ABSTRACT FROM PUBLISHER]

Copper is a crucial catalyst in the synthesis of graphdiyne (GDY). However, as catalysts, the final fate of the copper ions has hardly been concerned, which are usually treated as impurities. Here, it is observed that after simple washing with water and ethanol, GDY still contains a certain amount of copper ions, and demonstrated that the copper ions are adsorbed at the atomic layers of GDY. Furthermore, we transformed in situ the copper ions into ultrathin Cu nanocrystals, and the obtained Cu/GDY hybrids can be generally converted into a series of metal/GDY hybrid materials, such as Ag/GDY, Au/GDY, Pt/GDY, Pd/GDY, and Rh/GDY. The Cu/GDY hybrids exhibit extraordinary surface enhanced Raman scattering effect and can be applied in pollutant efficient enrichment and detection. [ABSTRACT FROM AUTHOR]

Copper is a crucial catalyst in the synthesis of graphdiyne (GDY). However, as catalysts, the final fate of the copper ions has hardly been concerned, which are usually treated as impurities. Here, it is observed that after simple washing with water and ethanol, GDY still contains a certain amount of copper ions, and demonstrated that the copper ions are adsorbed at the atomic layers of GDY. Furthermore, we transformed in situ the copper ions into ultrathin Cu nanocrystals, and the obtained Cu/GDY hybrids can be generally converted into a series of metal/GDY hybrid materials, such as Ag/GDY, Au/GDY, Pt/GDY, Pd/GDY, and Rh/GDY. The Cu/GDY hybrids exhibit extraordinary surface enhanced Raman scattering effect and can be applied in pollutant efficient enrichment and detection. [ABSTRACT FROM AUTHOR]

In this paper, a new environmental-friendly electrolyte containing sulfuric acid and tartaric acid has been used as the substitute of chromic acid for anodization. The work discussed the influence of anodizing voltages on the fatigue life of anodized 2024-T3 by performing fatigue tests with 0.1 stress ratio (R) at 320 MPa. Meanwhile the fatigue cycles to failure, yield strength, tensile strength and fracture surface of anodic films at different conditions were investigated. The results showed that the fatigue life of anodized and sealed specimens reduced a lot compared to aluminum alloy, which can be attributed to the crack sites initiated at the oxide layer. The fracture surface analyses also revealed that the number of crack initiation sites enlarged with the increase of anodizing voltage. [ABSTRACT FROM AUTHOR]

Effect of copper sulfate on alloys electroplating from non-cyanide baths are investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements are used to characterize the alloys electroplating system in order to analyze the nucleation and growth mechanism. The reduction of and alloy on sheet iron substrates shows an instantaneous nucleation process. However, the reduction of on sheet iron substrates shows a progressive nucleation process. The structure and surface morphology of alloys are analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The morphology of alloys obtained with 50 g L-1 copper sulfate presents a smooth and compact deposit and the size of crystal particle is uniform. [ABSTRACT FROM AUTHOR]

Non-cyanide alkaline bath was used to prepare copper thin films. Influences of various temperatures on deposition rates, surface morphologies and microstructures of films were investigated. Copper thin films prepared from non-cyanide alkaline bath show typical nodular structures. Copper films fabricated at higher temperature possess rough surface due to hydrolysis of complexing agents. According to the XRD patterns, all deposited films were crystalline and showed (111), (200) and (220) peaks. The intensity of peak (200) increases gradually with the rise on bath temperatures. Films with maximum thickness (7.5 μm) could be obtained at the temperature of 40°C. From the cyclic voltammetry curve, it was found that the cathodic polarization decreased slightly with increase of bath temperatures. In addition, when the bath temperature was equal to 50°C, current efficiency could reach to 96.95%. [ABSTRACT FROM AUTHOR]

Abstract: CoPtWP magnetic thin films were prepared by electroless deposition. The influence of bath pH, deposition temperature and bath composition on the deposition speed, alloy content, microstructure, and magnetic properties of CoPtWP thin films were investigated. It was found that deposition speed increased gradually with the bath pH and deposition temperature. The cobalt content in the CoPtWP thin films varied from 77at.% to 85at.% by controlling the bath pH. The microstructure of CoPtWP thin films was dependent on bath pH and deposition temperature: two mixed structures, face centered cubic (fcc) and hexagonal close packed (hcp), were observed at low pH values and low deposition temperature. With the increase of pH values and deposition temperature, the intensity of fcc (111) peak suppressed gradually. The surface morphology was markedly influenced by bath pH, deposition temperature and bath composition. VSM and MFM measurements revealed that perpendicular coercivity had been increased with the bath pH. Unique hard magnetic properties of CoPtWP thin films with large perpendicular magnetic anisotropy were obtained at 90°C and bath pH 13.0. [Copyright &y& Elsevier]

Abstract: Magnetic fields perpendicular to the copper substrate were applied during an electroless deposition process to obtain Co–W–P thin films from alkaline baths. Effects of different magnetic intensities, pH values and different powers of ultrasonic on the composition, microstructure and magnetic properties of Co–W–P alloys were investigated. Along with the increase of magnetic intensity, deposition speed and film thickness increased gradually as a result of the impacts of magnetic force and micro-MHD effect. Higher magnetic intensity could improve cobalt atomic percentage in the film and increase magnetization of Co–W–P films. Almost all of the deposited films were crystalline and contained hexagonal cobalt with a preferred crystallographic orientation (002). Dissimilar surface morphology could be detected under different pH values when 0.5T magnetic intensity was introduced, such as rice-like and needle-like structures. When magnetic field was applied during the electroless deposition, grains of films tended to grow perpendicularly to the substrate and hill-like structures would appear with the increase of magnetic intensity. It was also found out that hill-like structure thin films tended to have high coercivities. Hill-like structures could be smoothed when ultrasonic was applied during magnetic electroless deposition. Maximum coercivity (914Oe) could be obtained when 90W ultrasonic and B =0.5 T were introduced. [Copyright &y& Elsevier]

Abstract: Co–Pt–W magnetic thin films were electrodeposited from gluconate baths. Electrochemical characterization (polarization behaviors and transient curves), microstructure and magnetic properties were investigated. It turned out that increase in gluconate concentration and bath pH shifted the deposition potential to more negative potentials. Microstructure of electrodeposited Co–Pt–W thin films was affected by the bath pH and gluconate concentration enormously. Samples obtained from Co–sulphate–gluconate at pH 8.0 and gluconate concentration 0.3molL−1 exhibited single hcp phase with strong (001) PO. VSM and MFM measurement showed that perpendicular magnetic anisotropy occurred in the Co–Pt–W thin films prepared under these conditions. [Copyright &y& Elsevier]

Abstract: Complexing agents are often used to improve the quality of electrodeposited alloys. Influence of different complexing agents with hydroxycarboxylic acid group on the electrodeposited Co–Pt–W thin films has been investigated. Cathodic polarization curves show that the polarization behaviors of electroplating bath with different complexing agents are very different. Surface morphology, phase composition and magnetic properties are observed by means of FESEM, XRD and vibrating sample magnetometer (VSM), respectively. It has been found out that, if citrate was used as complexing agent, the Co–Pt–W thin films were homogeneous and the granular crystals with the average grain size of 2μm have been observed. Co–Pt–W thin films exhibited hexagonal close packed (hcp) lattice and strong perpendicular anisotropic magnetic behavior (H c⊥ =215.5kA/m; H c∥ =55.4kA/m). In the presence of gluconate, needle-like deposits were obtained and a strong face centered cubic (fcc(111)) texture was measured. The Co–Pt–W thin films showed isotropic magnetic behavior. In the case of tartate and malate, the coexistence of needle-like deposits and cellular deposits appeared. The XRD patterns showed that the mixed fcc and hcp phase formed. Perpendicular anisotropic magnetic behaviors of thin films, from malate or tartate baths, were not obvious. [Copyright &y& Elsevier]

Abstract: Co-W thin films were electrodeposited from aqueous bath with different organic additives. Electrochemical analysis showed that the transient state was limited and polarization behaviors were more evident during Co-W electrodeposition in the presence of organic additives. SEM measurement indicated that the surface morphology was affected by the nature of the organic additives to a large extent. Homogeneous Co-W thin films were obtained from the solutions containing ethyl methacrylate. Moreover, it was obvious that the presence of organic additives, in the electroplating bath, modified the structure and magnetic properties of the Co-W thin films according to the XRD and VSM measurements. [Copyright &y& Elsevier]

Recently Fe3O4 nanoparticles have been widely used in drug delivery systems due to their excellent magnetic properties and good biocompatibility. However, the surface of Fe3O4 nanoparticles is prone to agglomeration if it is not modified, which will affect his application performance. In this paper, Fe3O4 is hydrolyzed by ethyl orthosilicate (TEOS) and coated with SiO2 layer. Then the carbon layer is coated by hydrothermal reaction. Finally, SiO2 is etched by NaOH to form a kind of Fe3O4@C coreshell nanomaterials. The structure and morphology of Fe3O4@C nanoparticles were characterized by FT-IR, TEM and UV-Vis absorption spectroscopy, and the interface modification and related properties of nanoparticles are studied. The results show that the magnetic properties of Fe3O4 are not affected by the modified Fe3O4@C, and the specific surface area and the loading rate of Fe3O4are improved. The loading rate of Fe3O4reaches 98.9%. The drug release behavior of the compound interface modified Fe3O4@C under different pH conditions is further studied to explore the possibility that pH value could be used as a 'switch' for controlled drug release. [ABSTRACT FROM AUTHOR]

The noble metal-based electrochemical sensor design for efficient and stable formaldehyde(FA) detection is important ongoing research. In this paper, PtPd/Nafion/GCE is prepared by electrochemical cyclic voltammetry deposition method based on electrodepositing nanostructured platinum (Pt)-palladium (Pd) nanoparticles in Nafion film-coated glassy carbon electrode (GCE). The influence of deposition parameters and chemical composition (atomic ratio of Pt and Pd) on the electrochemical behaviour of PtPd/Nafion/GCE has been investigated. PtPd/Nafion/GCE displays a remarked electrocatalytic activity for the oxidation of FA and exhibits a linear relationship in the range of 10–5000 μ M, with a detection limit of 3.3 μ M in 0.1 M H2SO4 solution. It is proved that the detection performance of PtPd/Nafion/GCE electrode is valuable for further application with low detection limit, wide linear range, favourable selectivity and high response. [ABSTRACT FROM AUTHOR]

Water pollution caused by antibiotics is a growing problem and photodegradation by efficient catalysts is an environmentally friendly technology that can effectively degrade organic pollutants in water. Here, a novel method was innovatively used to synthesize niobium oxyfluoride (Nb3O7F) nanosheets decorated with Au nanoparticles, which is the first report for the composites of Au and Nb3O7F. We prepared the Nb3O7F nanosheets via hydrothermal synthesis followed by deposition of Au nanoparticles on their surface using HAuCl4. The prepared samples were characterized by XRD, HRTEM, XPS, and UV-Vis. The diameters of most Au NPs are ranging from 5 to 25 nm with an average size of about 16.9 nm, as well as the Nb3O7F nanosheets in size ranging from 200 nm to 700 nm. The chemical composition of the Au-Nb3O7F showed a Au/Nb atomic ratio of 1/10, as well as a Nb/O/F ratio of 3/7/1. UV-Vis spectrum reveals a largest absorption peak at 520 nm for the Au-Nb3O7F nanosheets. The prepared Au-Nb3O7F nanomaterials were applied to the visible-light photodegradation of tetracycline hydrochloride, with the photocatalytic degradation rate reached more than 50% under the optimal conditions within 1 h. Capture experiments indicated that h+ and «O2- are the main active substances involved during the course of the photodegradation. Furthermore, the proposed mechanism for the photodegradation of the novel Au-Nb3O7F nanosheets was given. [ABSTRACT FROM AUTHOR]

Coal mine methane (CMM) drainage is an effective method to curb the occurrence of coal and gas outburst and gas explosion, to reduce the amount of greenhouse gas emission, and to make full use of the clean energy(methane). Sealing in-seam horizontal boreholes plays a vital role in CMM drainage. Reasonable sealing length is an important factor to achieve high extraction efficiency and reduce the cost of construction. To determine the minimum reasonable sealing length of drainage boreholes, the radius of the fracture zone was obtained based on the ideal elastoplastic model, and this radius was taken as the minimum sealing length. The influencing factors of the minimum sealing length were analyzed and engineering verification test was taken in Zhongmacun mine in Henan province, China. The research results show that the minimum reasonable sealing length should be longer for a larger radius of the coal roadway and the coal seam with a deeper buried depth, while the minimum reasonable sealing length can be shortened with the increase of uniaxial compressive strength and the supporting stress of the coal roadway. The 11.07 m of sealing length calculated by theories was basically consistent with the 12 m of sealing length verified by the method of drilling cuttings. The reasonableness of sealing length (12 m) was verified by the test results of methane concentration and flux within 40 days. All those outcomes can provide references for other mines to determine the minimum reasonable sealing length of in-seam boreholes for CMM drainage. [ABSTRACT FROM AUTHOR]

Irregular Li deposition is the major reason for poor reversibility and cycle instability in Li metal batteries, even leading to safety hazards, the causes of which have been extensively explored. The structural disconnection induced by completely dissolving Li in the traditional testing protocol is a key factor accounting for irregular Li growth during the subsequent deposition process. Herein, the critical role played by the structural connectivity of electrochemical Li reservoir in subsequent Li deposition behaviors is elucidated and a morphology‐performance correlation is established. The structural connection and resultant well‐distributed morphology of the in situ electrochemical Li reservoir ensure efficient electron transfer and Li+ diffusion pathway, finally leading to homogenized Li nucleation and growth. Tailoring the geometry of Li reservoir can improve the coulombic efficiency and cyclability of anode‐free Li metal batteries by optimizing Li deposition behavior. [ABSTRACT FROM AUTHOR]

Irregular Li deposition is the major reason for poor reversibility and cycle instability in Li metal batteries, even leading to safety hazards, the causes of which have been extensively explored. The structural disconnection induced by completely dissolving Li in the traditional testing protocol is a key factor accounting for irregular Li growth during the subsequent deposition process. Herein, the critical role played by the structural connectivity of electrochemical Li reservoir in subsequent Li deposition behaviors is elucidated and a morphology‐performance correlation is established. The structural connection and resultant well‐distributed morphology of the in situ electrochemical Li reservoir ensure efficient electron transfer and Li+ diffusion pathway, finally leading to homogenized Li nucleation and growth. Tailoring the geometry of Li reservoir can improve the coulombic efficiency and cyclability of anode‐free Li metal batteries by optimizing Li deposition behavior. [ABSTRACT FROM AUTHOR]

Underground coalbed methane extraction is an important way for preventing coal mine gas disasters and reducing greenhouse gas emission, but air leakage around extraction boreholes is a critical factor that limits efficient coalbed methane extraction. Dynamically filling and plugging fractures around extraction boreholes can prevent air leakage. Due to the invisibility and complexity of underground geological formations, observing the process and effectiveness of plugging is extremely challenging. To visualize and quantitatively characterize the filling and plugging performances of fractures in coal. First, experiments are conducted to fill the coal damaged by the uniaxial and the triaxial loading-induced using a novel fracture filling experimental system under the constraint conditions. Then the multidimensional (point, surface, volume) plugging performances of fractures in coal before and after filling is visualized by the method of the X-ray computed tomography imaging. Finally, the quantitative characterization of filling and plugging performances of fractures in coal is conducted by testing changes in weight, fracture volume, and permeability before and after filling process. The experimental results show that after filling, the width and quantity of fractures in the coal significantly decreases, and the damaged coal is repaired. The filling ratio of fractures in coal fractured by uniaxial loading is 72%, and the fracture filling ratio in coal under triaxial loading is 68.1%. Under the influence of seepage and diffusion of plugging materials, the fractures are continuously filled, leading to a continuous decrease in the permeability of the fractured coal. The significant reduction in permeability of the fractured coal body is evident. The filling and plugging performances of fractures in coal is effective. The findings in this paper provide meaningful references and guidance for determining the filling and plugging parameters in underground gas extraction engineering practices. [ABSTRACT FROM AUTHOR]

The basin–mountain transition zone presents complex geologic structures and non-uniformly distributed in-situ stress. Studying the spatial distribution laws of in-situ stress and their influences on coalbed methane (CBM) occurrence in coal seams plays a significant role in CBM extraction and prevention of coalmine disasters. Based on the actual measured in-situ stress data, CBM content and gas pressure data in the Pingdingshan coalfield, located in the basin–mountain transition zone in the south of the late Palaeozoic basins in the North China block, this research investigated the distribution characteristics of geologic structures and partition of in-situ stress as well as the effects of in-situ stresses on CBM occurrence in the research area using evolution theories of geologic structure and a statistical analysis method. The research results show that geologic structure and in-situ stress distribution in the research area have obvious partition characteristics. The research area is divided into three tectonic zonations. In-situ stress distribution is controlled by tectonic types and tectonic stress field evolution of different tectonic zonations, which are divided into high tectonic stress zonation, tectonic stress zonation and vertical stress zonation from east to west. Also, the research results reveal the characteristics of each stress zonation and the relationship between CBM occurrence and in-situ stress in this research area. [ABSTRACT FROM AUTHOR]

• A dynamic anti-air-leakage method with a short sealing depth for in-seam boreholes was proposed. • A new organic polymer sealing material matches with this method. • The dynamic developing fractures zone is the main channel of air leakage during methane drainage. • The performance of methane drainage effects and economic benefits is remakable. Coal mine methane (CMM) drainage is an important method to curb the occurrence of gas disasters and to reduce the amount of greenhouse gas emission, and to make full use of the methane resource. High-grade sealing boreholes is the key factor to achieve efficient drainage of methane. In order to improve the efficiency of CMM drainage as well as to seal in-seam horizontal boreholes and fractures around these boreholes effectively, a dynamic anti-air-leakage method called the dynamic fractures filling technology was presented, and an organic polymer material called the PM sealing material matching with this technology was developed in this paper. Firstly, the destruction of coal body around boreholes because of a roadway and a borehole excavation was analyzed from the view of stresses, and the range of fractures zone caused by roadway excavation was determined, then the sealing technology and sealing principle of the novel technology were analyzed systematically. Moreover, the development process of the PM sealing material was introduced, and the influence of preparation parameters on material properties was investigated. Besides, taking the coal seam in the 39,021 Transportation Lane in the Zhongmacun Mine(China) as the test site of this study, the attenuation law of the methane concentration in drainage boreholes under different sealing depths was investigated via adopting the conventional sealing technology. Finally, the methane-drainage effect of the novel sealing technology and the conventional technology were compared. The results indicate that: (1) Both a roadway excavation and a borehole excavation will cause the redistribution of stresses of the original coal mass, and the coal structure around a drainage borehole has been destroyed in different degrees due to stresses overlapping effect. Moreover, the dynamic developing fractures zone is the main channel of air-leakage during drainage process. (2) The novel technology uses the conventional sealing system and the dynamic sealing system to seal drainage boreholes and dynamic development of fractures around them. (3) When the water-to-material ratio is 7:1 and the treatment temperature is 180 °C for 30 min, the PM material has the best performance. (4) Comparing with the conventional sealing technology, the novel technology has the obvious characteristics of short sealing depth, long efficient continuous drainage time and high drainage amount of methane. and its advantages of methane-drainage effects and economic benefits are remarkable. [ABSTRACT FROM AUTHOR]

We report a facile synthesis route to a series of high-quality carbon nanotube/metal oxide (CNT/MO) nanocomposites including CNT/Co 3 O 4 , CNT/SnO 2 , CNT/Fe 3 O 4 , and CNT/NGP (nickel glycolate polymer) without functionalization of pristine CNT. Using pristine CNT, various metal salts, and sodium acetate as raw materials, the CNT/Fe 3 O 4 and CNT/NGP nanocomposites were successfully synthesized via one-step solvothermal reaction, while the nanocomposites CNT/Co 3 O 4 and CNT/SnO 2 by an easy two-step process of solvothermal followed by heat treatment. The microscopic analysis revealed that the MO nanoparticles and NGP are uniformly deposited on the CNT's surface with high dispersion. This strategy is also applicable to decoration of CNT with other MO nanoparticles to form high-quality CNT/MO nanocomposites. • A facile synthesis route to various CNT/metal oxide nanocomposites is reported. • The pristine CNTs without functionalization are used directly. • The metal oxide nanoparticles with high dispersion are uniformly deposited on the CNT's surface. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SPE) offer an outstanding choice because of their lightweight, flexibility, and excellent thin‐film forming ability. However, the low ionic conductivity and poor lithium ion transfer number (tLi+) restrict its application in all‐solid‐state lithium batteries (ASSLBs). Herein, UIO66‐X metal‐organic frameworks with controllable Lewis basicity, acidity, or neutrality functional groups are synthesized successfully and then incorporated into the poly (ethylene oxide) (PEO) matrix to fabricate SPE. The influence of different organic ligands on the interface interaction between PEO and LiTFSI is investigated by solid‐state nuclear magnetic resonance, Fourier transform infrared spectoscopy and Raman tests, as well as density functional theory calculations. The Lewis acidity group plays a key role in enhancing the ionic conductivity and tLi+. As a result, the constructed Li–Li symmetrical cells retain stable cycling for 2300 h and the LiFePO4‐based ASSLBs deliver outstanding electrochemical properties with 147 mAh g−1 of reversible capacity after 500 cycles at 1C and 60 °C, 131 mAh g−1 after 150 cycles at 0.1C and 30 °C. The fabricated SPEs are self‐standing and flexible with good mechanical stability, demonstrating the great potential for practical application. The results can guide choosing the inorganic filler to prepare high‐performance SPE. [ABSTRACT FROM AUTHOR]

The corrosion behaviour and mechanism of CoCrNi medium-entropy alloy (MEA) imposed by alternating current (AC) in HCO3−/CO32− solution with various pH were systematically investigated via a series of corrosion tests. The results showed that with the augment of pH value, the polarisation resistance of the MEA decreased significantly, Ep shifted negatively, and ipI value increased, as well as corrosion rate was enhanced, revealing that the corrosion resistance was weakened. As solution pH increased, the formation of secondary passivation zone became easier, which may be attributed to the reaction conversion process of Cr(III) to Cr(VI) species. Moreover, the increase in pH led to an increase in defect density and a thinning of passivation film, facilitating the corrosion of the MEA. AC interference accelerated the ion exchange process and promoted the formation possibility of stable pitting. Higher iAC and pH inhibited the repassivation of metastable pitting, and increased the pitting susceptibility. Highlights The effect of pH on the corrosion behaviour of CoCrNi MEA with imposed AC was clarified. High pH and iAC accelerated the nucleation and growth of metastable pits. With increased pH and iAC, the stability and protective ability of passive film were weakened. The secondary passivation of the MEA was mainly due to the conversion of Cr(III) to Cr(VI) species. [ABSTRACT FROM AUTHOR]

Highly efficient and recoverable utilization of noble metals is desirable for catalyst design in the industrial application. Here we report one-dimensional (1D) chain-like Fe 3 O 4 @C/Pt sandwich nanocomposites obtained through a facile magnetic field-induced assembly followed by a simple adsorption-reduction method. Firstly, 1D Fe 3 O 4 @C core-shell nanochains are successfully synthesized by one-pot magnetic field-induced solvothermal reaction, using Fe 3 O 4 nanospheres and glucose as starting materials. Then, a trace of Pt nanoparticles with 2 ∼ 3 nm in size are uniformly immobilized onto the surface of the Fe 3 O 4 @C nanochains to form 1D chain-like Fe 3 O 4 @C/Pt sandwich nanocomposites via a simple adsorption-reduction method. Such 1D sandwich nanostructures endow the product with good magnetically recyclable catalytic performance towards hydrogenation reaction of ortho -chloronitrobenzene, where a complete conversion and stable selectivity to ortho -chloroaniline for four cycles are achieved. This work is helpful for rational design and development of highly efficient and recyclable catalysts based on noble metals. [ABSTRACT FROM AUTHOR]

The corrosion behavior and mechanism of CoCrFeNi HEA under AC application were systematically studied in 3.5 wt.% NaCl solution containing different concentrations of NaHSO3. The results showed that the existence of HSO3− increased the defect density within the passivation film on the surface of the HEA. With the increase of HSO3− concentration, the passivation zone became narrow, Ep shifted negatively, and ip increased, which indicated that the corrosion resistance of the HEA was weakened. When the HSO3− concentration increased to 0.1 M, a clear transition zone appeared, indicating that the increase in concentration reduced the passivity of the HEA, and its corrosion behavior changed from the typical passivation characteristic to the activation state with increasing iAC. The imposed AC promoted the nucleation of metastable pitting, which was indicated by a remarkable increase in the average pitting number density (Navg) from 5 to 17 mm−2 with the enhancement of iAC. [ABSTRACT FROM AUTHOR]

Underground gas extraction is an important technical means to solve coal mine gas disaster and utilize coalbed methane resource. Air leakage around extraction boreholes is a key factor for restricting the efficient gas extraction. Cement-based materials and polyurethane are currently the most widely used for plugging fractures to prevent air leakage. However, regenerated fractures can still develop under stress disturbances around boreholes after materials solidify. Regenerated fractures create new leakage pathways for external air to enter a borehole, significantly impacting the efficient extraction of gas. To overcome shortcomings of solid-phase materials in plugging fractures, based on the concept of "solid plugging liquid and liquid plugging gas", a novel dynamic filling material with superior stability, strong permeability, and adaptable performance is developed for plugging fractures in this paper firstly. Then the rheological properties, anti-interference properties, hydrophobic properties and water retention properties of the dynamic filling material are tested and the experimental results show that the addition of coupling agent can improve the rheological properties of the material; the intrusion of coal powder has little effect on destroying the stability of the material; the dense protective film formed by the material can effectively reduce the intrusion of external water and its own water loss. The properties of the materials modified with different additives had good mobility and stability, and can be used for plugging fractures around boreholes dynamically. Finally, the dynamic filling material is applied in underground gas extraction engineering in Tangshan Coal Mine. The field test shows that the average methane concentration of boreholes with the dynamic filling material plugging increases from 8 % to 24 %. The material is suitable for dynamic and long-term filling and leakage prevention in regenerated fractures in coal. [Display omitted] • A novel dynamic filling material with superior stability, strong permeability, and adaptable performance is developed for plugging fractures. • Rheological properties, anti-interference properties, hydrophobic properties and retention properties of the material are investigated. • The average methane concentration of boreholes with the dynamic filling material plugging increases from 8 % to 24 %. [ABSTRACT FROM AUTHOR]

Solar energy is an eco-conscious substitute, for solar energy absorption and subsequent light-to-heat conversion, light-absorbing materials require broad-spectrum light absorption capabilities. Herein, we present the fabrication of broadband light-absorbing polypyrrole-carboxylated carbon nanotube membranes via a facile electrochemical deposition route. By manipulating electrochemical deposition time, the structure of the membranes was tailored, resulting in enhanced absorption, achieving over 98.95 % across the entire solar spectrum. The membranes demonstrated exemplary thermal efficacy and insensitivity to incident angles in photothermal conversion, the membranes facilitated a notable 12 °C temperature elevation within a simulated greenhouse compared to ambient conditions. Thus, these membranes exhibit considerable potential for widespread application in photothermal conversion and greenhouse technology. [ABSTRACT FROM AUTHOR]

Core-shell CsPbBr 3 @SiO 2 composite has been successfully prepared and firstly applied in the photocatalytic degradation of antibiotic residues in water, showing good activity and stability. [Display omitted] • Core-shell CsPbBr 3 @SiO 2 with good water-resistance was successfully constructed. • The experimental parameters influencing the formation is intensively investigated. • CsPbBr 3 @SiO 2 can photodegrade antibiotic residue in water efficiently. • CsPbBr 3 @SiO 2 has good cycling and storage stability in aqueous photocatalysis. All-inorganic perovskite cesium lead bromide (CsPbBr 3) is hardly applied in direct aqueous photocatalysis due to its instability in water although it has received considerable attention in solar energy conversion. Herein, core-shell cesium lead bromide-silica (CsPbBr 3 @SiO 2) has been prepared by a simple precipitation coating method and applied in visible-light-induced photodegradation of antibiotic residue in water for the first time. The obtained CsPbBr 3 @SiO 2 composite exhibits tunable photocatalytic activity according to the precursor ratios and the maximum achieves at lead bromide/tetramethoxysilane (PbBr 2 /TMOS) molar ratio of 1:5. Electrochemical and photoluminescence analyses indicate that the introduction of SiO 2 results in promoted photo-generated current and reduced impedance, which reduces the photo-induced electron-hole recombination and/or the energy barrier of the interfacial reaction between the formed perovskite particulates. Holes (h+) and superoxide radicals (O 2 −) are identified as active substances for photodegradation activity. This work demonstrates the application of all-inorganic halide perovskite in efficiently treating refractory contaminants in water, which provides an alternative approach for utilizing inorganic perovskites and new ideas for developing high-efficiency photocatalysts. [ABSTRACT FROM AUTHOR]

In this study, a simple, sensitive, and rapid method was developed for the simultaneous determination of 99 kinds of pesticides in fatty milk samples. This novel emulsification-demulsification clean-up approach, coupled with an automatic demulsification-dehydration cartridge, allowed rapid single-step clean-up operation and high throughput. It also achieved effective and selective removal of lipids. The analysis was performed using low-pressure gas chromatography-tandem mass spectrometry (LPGC–MS/MS). Based on the optimal conditions, the targeted pesticides showed good linearity in the range of 5–250 μg/kg, with recoveries of 70–120% at spiking levels of 5, 10, and 20 μg/kg in cow milk, goat milk, and almond milk, respectively. The limit of quantification for most pesticides was 5 μg/kg, and the RSDs were lower than 20%. Analysis of real dairy products obtained from local markets revealed a potential risk in plant-derived almond milk, but no significant risks were found for cow and goat milk. • Different clean-up methods were compared for multi-residue analysis in dairy products. • A single-step emulsification/demulsification clean-up procedure was established. • LPGC-MS/MS method was optimized and evaluated. • The LOQ was 5 μg/kg for majority of pesticides, below the established MRLs. • Main advantages of the method: simplicity, high throughput, reliably of results. [ABSTRACT FROM AUTHOR]

In this work, wear mechanisms of electrodeposited Ni–W and Ni–W/Al 2 O 3 coatings sliding against Si 3 N 4 and AISI 52100 steel have been comparatively studied. For both Ni–W and its composite coatings sliding against Si 3 N 4, worn morphology shows the tribochemical reaction (tribooxidation) followed by abrasive wear is the dominated mechanism. Comparing with Ni–W coatings, the protective oxide layer is slower peeled off at tribooxidation stage and wear debris are easier squeezed on the Ni–W/Al 2 O 3 during abrasive wear stage. The incorporated Al 2 O 3 provide load bearing effect during microploughing and improve the wear resistance. As sliding against AISI 52100 steel, wear rate of Ni–W/Al 2 O 3 is several times higher than that of Ni–W coatings. Conformity between surfaces of the Ni–W coating and counterbody leads to mild smoothening wear, while the plastic deformation dominated delamination makes severe wear of Ni–W/Al 2 O 3. Deformation resistance of the coatings and transition of counterbodies materials from ceramic to hard metal are responsible for the different wear mechanisms. For Si 3 N 4 ceramic, low thermal conductivity leads to tribooxidation followed by abrasive wear of both Ni–W and Ni–W/Al 2 O 3 coatings. Relatively high deformation resistance of Ni–W coatings is responsible for the conformity as the premise for mild wear sliding against AISI 52100. Low deformation resistance of composite coatings induced by weak interfaces between Al 2 O 3 and Ni–W matrix makes delamination sustained. • Effect of counterbodies on wear behavior of Ni–W and Ni–W/Al 2 O 3 coatings is revealed. • Against Si 3 N 4 or AISI 52100, Ni-W/Al 2 O 3 has better or much worse anti-wear than Ni-W. • Wear mechanism of Ni–W and Ni–W/Al 2 O 3 vs. Si 3 N 4 is tribooxidation followed abrasion. • Ni–W and Ni–W/Al 2 O 3 vs. AISI 52100 exhibit mild smoothening and severe delamination. • Deformation resistance of coatings are responsible for wear mechanisms. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) perovskite materials, are more stable than 3D perovskite materials, which could solve the stability issue of perovskite solar cells (PSCs). However, the photovoltaic conversion efficiency (PCE) of PSCs based on 2D perovskite materials was low, due to the high dielectric and quantum confinement of 2D perovskite. In this work, we propose a solvent-assisted method to prepare 2D perovskite films, where the solvent was distributed in a gradient. Therefore, the top-down crystallization process of 2D perovskite can be accurately controlled. The PCE of PSCs fabricated by the solvent-assisted method was enhanced by 48%, compared with the control device. For the packaged devices, the stability test demonstrated that 94% of the initial PCE was still maintained after 1500 hours of storage (25 °C, RH 40%). After carefully analyzing the photophysical process of the carriers in the PSCs based on 2D perovskite, the enhanced carrier transfer mechanism of the solvent-assisted method has been proposed. [ABSTRACT FROM AUTHOR]

Thermo-anodization technology has been considered as an effective means to improve the thermal, physical and chemical properties for metal alloy. In this work, we achieve a porous black layer on the surface of aluminium alloy through an environmentally friendly anodic oxidation process, with a high thermal emittance (0.96) and a high solar absorptivity (0.921). In addition, the black thermo-anodized coating layer shows a unique anti-corrosion property under UV irradiation. A hybrid hydrophobic surface has been facilitated through treating the thermo-anodized porous layer with silane. Moreover, an anti-icing feature can be realised that can effectively delay the freezing of water droplet on the surface of AA2024 aluminium alloy. As such, the specific anodic process of coating provides a simple method for improving the solar absorptivity and infrared emittance of aluminium alloys, enabling broad applications in aerospace engineering. Unlabelled Image • Creating a porous black surface on aluminium alloy in a controllable fashion. • The resulting coating achieves high thermal emittance (0.96), high solar absorptivity (0.921) and unique UV resistance. • A unique anti-icing feature can be realised by effectively delaying the frozen of water droplet. [ABSTRACT FROM AUTHOR]

The study of coal adsorption-induced strain is of great significance to the development of coalbed methane (CBM). In this text, the relationship between adsorption-induced strain and injection time, injection pressure, flux and permeability were studied by He and N 2 injection respectively. The variation of adsorption strain with time at different stages was mainly studied. It was found that the strain increases linearly with increasing injection pressure within the experimental range. The relationship between strain and time is according to Langmuir's law under the same injection pressure. Meanwhile, there is a free adsorption boundary in the initial linear stage of adsorption. Within the free adsorption boundary, the adsorption-induced strain rate is independent of pore pressure; afterwards the adsorption-induced strain rate begins to be dominated by pore pressure. Moreover, the permeability increases with the increase of pore pressure. Because of the negative effect of adsorption expansion, the variation of N 2 permeability with injection pressure is slower than that of He. The lower the initial permeability is, the more serious the permeability damage caused by adsorption expansion will be. The final research results show that pore pressure has a dual effect of "one positive and one negative". The positive effect is the promotion of gas migration, and the negative effect is the inhibition of adsorption expansion on gas migration. • Pore pressure has a dual effect of "one positive and one negative". • Variation of adsorption strain with time at different stages was analyzed. • The concept of free adsorption boundary was proposed. • The relationship between permeability and adsorption deformation was analyzed. [ABSTRACT FROM AUTHOR]

As a hole transport materials (HTMs) and noble-metal free perovskite solar cells (PSCs), carbon-based PSCs (C-PSCs) have drawn much attention due to its low cost and excellent stability. The interfacial engineering, between perovskite and counter electrodes (CEs), played a crucial role in charge collection and affected the performance of C-PSCs. Herein, the systematic investigation of interfacial bridging carbon materials has been carried out to improve the interfacial contact. Results demonstrated that the morphology of interfacial bridging carbon materials played more important role than their energy band and conductivity, where carbon nanotube (CN) showed much better interfacial bridging effect and energy level alignment than other carbon materials. We achieved both the high power conversion efficiency (PCE) (15.09%) and stability in C-PSCs without HTMs due to the optimal interfacial bridging carbon material. It could retain 67% of their initial PCE after storing for 340 h under the rigorous environmental condition without any encapsulation (air atmosphere, 85 °C, 65% RH). [ABSTRACT FROM AUTHOR]

One of the major problems limits the applications of perovskite solar cells (PSCs) is the high cost of hole transporting materials (HTMs) and noble metallic electrodes. For HTMs and noble-metal-free PSCs, carbon materials have been utilized as counter electrodes (CEs). In this paper, four kinds of ultra-low-cost bio-carbon materials have been applied and compared in PSCs. Results showed that the photovoltaic performance of PSCs based on different bio-carbon CEs was determined by the interfacial connection, work function (WF), sheet resistance, crystallinity, and morphology of these bio-carbons. The high PCE (12.82%) of PSCs based on bio-carbon CEs has been achieved in current state-of-the-art. PSCs based on bio-carbon CEs was more stable than that of conventional devices, which could retain 87% of their initial PCE after storing for 2000 h in room temperature. Our work proposes a new pathway for the exploration of low-cost bio-carbon materials and could accelerate the applications of PSCs based on carbon electrode. Image 1 [ABSTRACT FROM AUTHOR]

Insufficient durability and adhesion of coatings are two major bottlenecks that constrain their application in marine environments. In our study, the uniform cerium containing silicon acrylate coatings with excellent bonding strength were prepared on the surface of Q235 steel through electrosynthesis method, and the optimal preparation temperature was 60 °C. The water contact angle of the coating was 108.8°, increased by 76.3° compared with the blank substrate and the corrosion protection efficiency reached 93.9 %. Through scratch testing, the binding force level reached 5B according to the ASTM D3359-09. After being exposed to the natural environment for three months, the coatings' surface shown no corrosion marks, proving that the coatings have a certain degree of stability. The bend test result shows excellent strength of the coatings. The successful preparation of coatings on irregular structures indicates good suitability of the coatings. The synthesis mechanism of the cerium containing silicon acrylate coatings and the effect of temperature on the formation of the coating are discussed in detail. The fabrication of cerium containing silicon acrylate coating on the substrate surface through electrochemical synthesis method can greatly improve the adhesion between the coating and the substrate, thereby extending its service life. This study provides a simple and mild approach to prepare acrylic resin composite coatings with good adhesion, strength, hydrophobicity and corrosion resistance. [Display omitted] • Cerium containing silicon acrylate coating was prepared by electrosynthesis method. • Providing new ideas for surface protection of precision components • Introducing the effect of different preparation temperatures on coatings • The synthesis mechanism of the composite coating was discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • A temperature induced wear mechanism transition of Ni-Co-W coating has been found. • Effect of load, velocity and temperature on wear behavior has been revealed. • Relationship between frictional conditions and wear mechanism has been elucidated. A temperature induced wear mechanism transition of electrodeposited Ni-Co-W alloy coatings has been revealed. At room temperature, the wear rate of the coating exhibits little variation with sliding velocity or normal load. From 100 °C to 300 °C, the wear resistance of the coating is enhanced at high sliding velocity or high normal load. With increase of ambient temperature, the wear mechanism turns from typical abrasive wear with significant parallel grooves and wear debris on the worn tracks to mild oxidative wear with shallow grooves and adhered oxide layer on the worn surfaces. The improved wear resistance at high temperature can be ascribed to the transition of wear mechanism and the formation of uniform oxides layer covered on the worn surface. [ABSTRACT FROM AUTHOR]

The instability of lattice oxygen and the resulting chain reactions mainly originate at the interface between the electrolyte and the outmost surface of Li-rich Mn-based cathode materials (LRM). Although many research works are focused on improving the cycling performances of LRM by surface protection, the issue of voltage fading is still severing. To overcome the challenge, the MgNiO 2 surface heterointerface layer is constructed on the surface of cobalt-free LRM to form a heterointerface in this work, which can suppress side reactions at the interface, inhibit the dissolution of Mn elements, enhance the lattice oxygen stability, and stabilize the crystal structure. Benefiting from the above merits, the voltage fading value of the modified sample has been decreased by 28.2%. And the specific capacity retention of the modified sample (92.9%) is significantly higher than that of the pristine sample (80.9%). This work provides a valuable idea for optimizing the surface to improve the electrochemical performance of high-specific capacity Li-rich cathode materials. A MgNiO 2 surface heterointerface layer was constructed at the surface of cobalt-free Li-rich Mn-based cathode materials (MNO-LRM). The introduced MgNiO 2 layer can reduce the interface side reaction, mitigate the Mn dissolution, and stabilize the crystal structure. As a result, the designed MNO-LRM exhibits excellent voltage and cycling stability. [Display omitted] • A MgNiO 2 surface heterointerface layer is constructed in the Li-rich cathode. • The surface heterointerface layer enhances the interfacial and structural stability. • The MgNiO 2 -modified cathode exhibits enhanced electrochemical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] Oily sewage has made serious impact on environment and people's life, and its treatment has become a global problem to be urgently solved. Oil-water separation has been considered to be an effective method to treat oily sewage at present. In this work, an underwater super-oleophobic/super-hydrophilic membrane with oil-water separation and self-cleaning properties was fabricated by electrochemical oxidation of sodium lignosulfonate doped polypyrrole. The membrane showed super-hydrophilicity for water-removal in air and super-hydrophilicity for oil-removal underwater in both oxidation and reduction states. The oil-water separation efficiency of the membranes for different organics exceeded 98.44%, no matter in oxidation or reduction state. Moreover, the membrane still exhibited excellent performance in terms of the oil-water separation efficiency and flux after 70 cycles, which were greater than 97.18% and 70.14 L·m−2·h−1, respectively. Simultaneously, through exploration of the mechanism, it was found that the larger anion kept intact in the membrane during the redox process, which made the stability of composition and performance. Thus, the membrane with advantageous properties, including underwater super-oleophobic/super-hydrophilicity, high oil-water separation efficiency, high circulating rate and stability, has significant potential in separation and collection of oily sewage. [ABSTRACT FROM AUTHOR]

Magnetic field parallel to electric field was induced during plating process to prepare CoNiMn alloy films on copper substrate. Electrochemistry mechanism and properties of CoNiMn alloy films were investigated in this paper. Micro magnetohydrodynamic convection phenomenon caused by vertical component of current density and parallel magnetic field due to deformation of current distribution contributed directly to the improvement of cathode current and deposition rate. Cathode current of the CoNiMn plating system increased about 30% with 1T magnetic field induced. It was found that CoNiMn films electrodeposited with magnetic fields basically belonged to a kind of progressive nucleation mode. Higher magnetic intensity intended to obtain CoNiMn films with good crystal structures and highly preferred orientations. With the increase of magnetic intensities, surface morphology of CoNiMn alloy films changed from typically nodular to needle-like structures. Compared with coatings electrodeposited without magnetic field, CoNiMn alloy films prepared with magnetic fields possessed better magnetic properties. Coercivity, remanence and saturation magnetization of samples increased sharply when 1T magnetic field was induced during plating process. [ABSTRACT FROM AUTHOR]

Traditionally, the evaluation of pollen-based quantitative paleoclimate reconstructions focuses on the ability of calibration sets to infer present climatic conditions and/or the similarity between fossil and modern assemblages. Objective criteria for choosing the most appropriate climate parameter(s) to be reconstructed at a specific site are thus lacking. Using a novel approach for testing the statistical significance of a quantitative reconstruction using random environmental data, in combination with the advantageous large environmental gradients, abundant vegetation types and comprehensive modern pollen databases in China, we describe a new procedure for pollen-based quantitative paleoclimatic reconstructions. First, the most significant environmental variable controlling the fossil pollen assemblage changes is identified. Second, a calibration set to infer changes in this targeted variable is built up, by limiting the modern ranges of other environmental variables. Finally, the pollen-based quantitative reconstruction is obtained and its statistical significance assessed. This novel procedure was used to reconstruct the mean annual precipitation ( P ) from Gonghai Lake in the Lvliang Mountains, and Tianchi Lake in the Liupan Mountains, on the eastern and western fringe of the Chinese Loess Plateau, respectively. Both P reconstructions are statistically significant ( p<0.001), and a sound and stable correlation relationship exists in their common period, showing a rapid precipitation decrease since 3300 cal yr BP. Thus, we propose that this procedure has great potential for reducing the uncertainties associated with pollen-based quantitative paleoclimatic reconstructions in China. [ABSTRACT FROM AUTHOR]

Cobalt films were electrodeposited on glassy carbon surface in the experiment to study the electrochemistry mechanism. Cobalt electrodeposition process was investigated by cyclic voltammetry, chronoamperometry, polarization curves and so on. It was found that cobalt started to deposit combined with hydrogen evolution at −0.3 VSCE. Hydrogen evolution was dominated from −0.3 to −0.9 VSCE. However, with the voltages increased from −0.9 to −1.1 VSCE, cobalt deposition was predominated. Cyclic voltammetry curves with different scan rates indicated that cobalt deposition was a kind of irreversible and diffusion-controlled process. According to typical nucleation model promoted by Scharifker and Hills, the results from chronoamperometry curves verified that cobalt electrodeposition on glassy carbon belonged to three-dimensional models with instantaneous nucleation. Cobalt films were a kind of grain films with typical nodular structures because of three-dimensional instantaneous nucleation mechanism. [ABSTRACT FROM AUTHOR]

Q235 steel, whose nominal composition (wt%) is 0.14–0.22 C, 0.30–0.65 Mn, ≤0.30 Si, ≤0.045 P, ≤0.055 S and Fe balance, has played an important role in the development of human history and the establishment of modern industry due to its excellent mechanical and engineering performance. In this study, black Ni Ce oxide composite coatings were electrodeposited on Q235 steel under photo-illumination and the effect of potential was studied. A 300 W ultra-high power xenon lamp with 300–2500 nm wavelength was the light source and provided 220,000 Lux irradiation intensity. After deposition of 40 min, black, uniform, and compact coatings were obtained; their colour gradually deepened when the potential changed from −0.7 to −0.9 V vs. saturated calomel electrode. The composite coatings improved the corrosion resistance of the substrate. Ni and Ce(III) content in the composite coating increased, whereas the hardness decreased at a more negative deposition potential. A black composite coating with both high absorptivity and high emissivity was obtained at a deposition potential of −0.8 V with photo-illumination, which exhibited an emissivity of 0.846 and absorptivity of approximately 95 % in the ultraviolet band, 90 % in the visible region, and 92 % in the near-infrared band. Exposure experiments showed that the absorptivity and emissivity decreased very little on exposing to a natural environment for one month. The electrodeposition mechanism and possible reasons for the above behavior are discussed in detail. The study provides an idea to prepare black coatings with high absorptivity and emissivity that are expected to be used in the naval, aerospace industry, photothermal conversion and optical instruments. • Black Ni Ce oxide composite coatings were electrodeposited with photo illumination. • Coatings with high emissivity, absorptivity and functional stability were obtained. • The electrodeposition mechanism of Ni Ce oxide composite coatings was discussed. [ABSTRACT FROM AUTHOR]

Effects of the different ultrasonic powers on copper electrodeposition from non-cyanide alkaline baths by using pyrophosphate as complexing agent were investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements were used to characterize the nucleation and growth mechanism. It is very obvious that the reduction potential moves to more positive one as the ultrasonic power increases. The quartz crystal microbalance (QCM) and chronoamperometric method were used to study the relationship between the mass change and the deposition time. It was found that the current efficiency of electrolyte under 0, 60, 80 and 100 W is 91.95%, 92.14%, 89.25% and 96.11%, respectively measured by QCM measurements. The surface morphology of the electrodeposited films is analyzed by scanning electron microscopy (SEM). The morphology of copper films electrodeposited under the power of 60 W and 80 W presents a compact surface and the grains are fine and uniform. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZIF-78 membrane was synthesized on porous silica support by secondary growth method. [•] Amorphous precursors were used as seeds for the growth of ZIF-78 membrane. [•] MOF membrane was applied for the first time in cyclohexanone/cyclohexanol separation. [ABSTRACT FROM AUTHOR]

Abstract: Electroless deposition technology has been considered as a kind of common ways to obtain cobalt alloy films. However, in order to get cobalt alloy films, high temperature (353K) is necessary during the electroless deposition process which will increase costs and energy consumption. Ultrasonic was introduced during electroless plating process to obtain cobalt alloy films at lower initial temperature. It was found that the cobalt thin films could be prepared at lower initial temperature (323K) with the introduction of ultrasonic. Therefore, different powers of ultrasonic were applied during the electroless deposition process to prepare CoP thin films on copper substrates from an alkaline bath in this investigation. The effects of different powers of ultrasonic on deposition rate, surface morphology, anticorrosion performance and magnetic property of films were studied. It was found that the deposition rate increased gradually with the rise in ultrasonic powers due to cavitation phenomenon. All the CoP films presented the typical spherical nodular structures with the impact of ultrasonic. Smaller and regular shaped structures could be observed when the films were deposited with higher power of ultrasonic which contributed directly to enhancement of anticorrosion performance. Saturation magnetization and coercivity of thin films increased gradually with the rise in ultrasonic powers during the electroless deposition process due to the higher amounts of cobalt. [Copyright &y& Elsevier]

As a salt of cyameluric acid and a derivative of tri-s-triazine, rod-shaped potassium cyamelurate K 3 [C 6 N 7 O 3 ] has been synthesized and employed as a homogeneous photocatalyst for photodegradation of aquatic tetracycline hydrochloride (TC-HCl) under visible-light irradiation for the first time. The water-soluble K 3 [C 6 N 7 O 3 ] owns excellent visible-light-driven photocatalytic activity, which is approximately 9 and 10 times higher than those on melon and g-C 3 N 4 in water, respectively. The photocatalytic process is investigated experimentally and theoretically, and the active centers of K 3 [C 6 N 7 O 3 ] are identified by first principles calculations. The active radicals for the photodegradation are identified and a reaction mechanism is proposed. Moreover, K 3 [C 6 N 7 O 3 ] can also work as an efficiently heterogeneous photocatalyst for the removal of TC-HCl in ethanol. This work provides a novel photocatalyst bridging homogenous and heterogeneous photocatalysis for environmental protection and opens a new application space for alkali cyanurates. [Display omitted] • K 3 [C 6 N 7 O 3 ] bridges the homogeneous and heterogeneous visible-light-driven photocatalysis. • K 3 [C 6 N 7 O 3 ] is efficient for homogeneously visible-light photodegradation of TC-HCl in water. • K 3 [C 6 N 7 O 3 ] is active for heterogeneously visible-light photodegradation of TC-HCl in ethanol. • The active centers of K 3 [C 6 N 7 O 3 ] are identified by first principles calculations. • The photocatalytic process is investigated and reactive radicals are identified. [ABSTRACT FROM AUTHOR]