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The sluggish kinetics of the oxygen evolution reaction (OER) limits the development of water electrolysis technology and the long-term efficiency of hydrogen energy production. In addition, it is important to evaluate the reconstruction performance of OER catalysts for actual water electrolysis. We created a self-supported electrode with FeS film coated Fe foam as a substrate, ordered resoluble molybdate (MoO 4 2−) anions in interlayers, and Co-doped as a catalytically active phase for the OER. The catalyst is capable of electrochemical self-reconstruction (ECSR). With the dissolution of molybdate and sulfur ions, the catalyst surface cobalt iron oxide (CoFe 2 O 4) forms an active amorphous FeCoOOH, which is favorable for alkaline OER. We realized the introduction of new active sites in the catalyst reconstruction process. Finally, the composite CoFeO x catalyst increased the specific surface area, promoted bubble transport, and enhanced electron mass transfer. The synergistic coupling effect of the catalyst makes it have excellent OER activity and stability. Remarkably, Co–Mo/FeS nanosheets afforded an electrocatalytic OER with a current density of 100 mA cm−2 at a low overpotential of 321 mV. These discoveries open up new opportunities for the application of doping and template-directed surface reconfiguration, which holds promise as an effective electrocatalyst for the OER. [Display omitted] • Hydrothermal and electroactivation methods to synthesis Co–Mo/FeS. • Doping Co to increase active sites. • Rapid dissolution of MoO 4 2− facilitates deep surface reconstruction of CoFe 2 O 4. • The synergistic effect of MoO 4 2− and Co increases the FeS intrinsic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • S-doping can increase valence of Co/Fe and reduce oxygen vacancies formation energy. • Regulating the hybridization effects between Co/Fe 3d and O 2p by S is the key. • The optimized S-CoFe-t exhibits an overpotential of 361.1 mV at 100 mA cm−2 for OER. • Vertical FeCoOOH is generated with the extraction of S after a long stability test. Reasonable design and manipulation of appropriately activated lattice oxygen on the catalytic surface is key to efficient oxygen evolution reaction (OER). Utilizing anionic regulation mechanism, partial and rapid sulfur (S) substitution for oxygen can provide optimal surface reconstruction of CoFe oxo/(hydroxo)ide materials during the OER process. S-doping can modulate the local electronic structure of CoFe oxo/(hydroxo)ide compounds, thereby reducing the oxygen vacancies formation energy. This is the first gradient to form more oxygen vacancies, thus activating lattice oxygen. In addition, the hybridization between Co/Fe 3d and O 2p is enhanced by the trace S doping on the surface of CoFe oxo/(hydroxo)ides, suggesting a faster rate of electronic transfer. Therefore, the electrochemical measurements show that the obtained electrocatalyst demonstrates an overpotential of 361.1 mV at 100 mA cm−2 and long-term stability. The characterizations after stability tests confirm that surface S was rapidly leached to form a second gradient high concentration oxygen vacancies. Moreover, the formation of uniformly dispersed vertical nanoplate arrays of FeCoOOH exposes a wealth of active sites. This work provides a promising ladder regulation strategy of lattice oxygen for the design of pre-catalysts for the development of large-scale water decomposition systems. [ABSTRACT FROM AUTHOR]

Abstract: Daptomycin, a novel cyclic lipopeptide antibiotic against Gram-positive bacteria, is produced by Streptomyces roseosporus. Though its biosynthetic mechanism, structural shuffling and fermentation optimization have been extensively studied, little is understood about its production regulation at the transcriptional levels. Here we reported that dptR2, encoding a DeoR-type regulator located close to the daptomycin biosynthesis gene cluster in S. roseosporus SW0702, is required for daptomycin production, but not for the expression of daptomycin gene cluster, suggesting that DptR2 was not a pathway-specific regulator. Furthermore, EMSA and qRT-PCR analysis suggested that DptR2 was positively auto-regulated by binding to its own promoter. Meanwhile, the binding sites on the dptR2 promoter were determined by a DNase I footprinting assay, and the essentiality of the inverted complementary sequences in the protected region for DptR2 binding was assessed. Our results for the first time reported the regulation of daptomycin production at the transcriptional level in S. roseosporus. [Copyright &y& Elsevier]

Abstract: Aluminum film deposited on GFRP, in this paper by cathodic arc technology for decreasing the reflect wastage. The aluminum film have been characterized by pull test, Dektak 8 Stylus Profilometer, SEM, XPS, XRD and Z-82 standard four probe. The results show that the aluminum film, be compose of face centered cubic (fcc) structure, is compact, uniform. And the resistivity of film is close to bulk aluminum. The XPS spectra show that the Al-C, Al-O bonds were created in film deposition process. [Copyright &y& Elsevier]

Biodegradation of wood chips of broad-leaved trees Eucalyptus grandis×Eucalyptus urophylla and Populus canadensis, and of the conifer Larix olgensis by Pseudomonas sp. PKE117 was studied. After 60 days of biopulping by PKE117, the weight losses of E. grandis×E. urophylla, P. canadensis and L. olgensis were 7.58%, 17.15% and 26.75%, respectively. Elemental analysis showed that the C, H contents of three wood chips decreased and O content increased after the biopulping. FT-IR results also showed that the lignin structure was destroyed more than that of cellulose. Solid-state CP/MAS 13C-NMR spectroscopy results showed that the content of guaiacylpropanoid (G) lignin-unit in lignin of three samples decreased after biodegradation. The hemicellulose in L. Olgensis decreased much more than other samples. All the results demonstrated that the degradation of L. olgensis by Pseudomonas sp. PKE117 was more efficient than that of P. canadensis and E. grandis×E. urophylla. The strain Pseudomonas sp. PKE117 could be an alternative bioagent to replace the white-rot fungi in the biopulping of softwood. [Copyright &y& Elsevier]

Developing highly efficient and stable noble metal-free electrocatalysts with excellent catalytic surface for oxygen evolution reactions (OER) is an essential link for stimulating hydrogen generation from water electrolysis. Herein, the scalloped nickel/iron vanadium oxide coated vanadium dioxide (named as VO 2 @NFVO) has been successfully decorated via a urea-induced chemical etching-reconstruction process in the alkaline solution containing Fe2+ and Ni2+. Corresponding experimental measurements clearly show that favorable chemical etching occurs with the formation of new phases (eg, Ni 3 V 2 O 8 , FeVO 4), which make it expose a large number of active sites and regulate the electron density of the active center, thus thereby dramatically enhancing the electrocatalytic performance by promoting electron transfer and optimizing the adsorption energy of reaction intermediates. Under optimized condition, the obtained VO 2 @NFVO delivers excellent activity merely with smaller overpotential of 290 mV at 10 mA cm−2, outperforming benchmark RuO 2 catalyst in an alkaline solution. Moreover, its superior durability is verified by chronoamperometry testing. This simple etching-reconstruction strategy opens a new avenue for the preparation of vanadium-based electrocatalysts. [Display omitted] • Urea-induced chemical etching promotes the exposure of more active sites for inert vanadium dioxide. • The new phase obtained by the reconstruction can tune the electron density of the active center and facilitate mass transfer. • The synergistic effect existing between Ni or Fe and vanadium oxide facilitates OER. • VO2@NFVO delivers excellent activity merely with smaller overpotential of 290 mV at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Transition metal selenides are promising oxygen evolution reaction (OER) catalysts, and element doping is a strategy to further enhance their catalytic performance. However, the choice of doping elements and methods needs further study. In this work for cobalt selenide, Ni is has been selected for isomorphic doping to NiCoSe 2 with silver doped in bulk to obtain Ag–NiCoSe 2 nanosheet on NF. The addition of nickel can form a eutectic phase with cobalt to obtain an effective synergistic catalytic effect. The addition of Ag can regulate the adsorption energy of the active site and conductivity. The as-prepared Ag–NiCoSe 2 /NF has good catalytic performance for OER, and a current density of 100 mA cm−2 can be achieved with only 270 mV. Its catalytic ability is far superior to that of non-Ag-doped NiCoSe 2 , which is due to the fact that the sheet structure provides more active sites, and the metal doping modulates the electronic configuration, which effectively improves the intrinsic activity. Moreover, Ag–NiCoSe 2 /NF can maintain a long-term high-efficiency catalytic process for more than 20 h at a current density of 100 mA cm−2. Therefore, this work proves that metal doping is of great significance for improving the catalytic activity of transition metal selenides. [Display omitted] • Ag–NiCoSe 2 on NF is prepared by electrodeposition and hydrothermal reaction. • Ag doping can improve the intrinsic activity and conductivity of NiCoSe 2. • Ag–NiCoSe 2 /NF requires 270 mV at 100 mA cm−2 for OER. • Ag–NiCoSe 2 /NF operates stably for at least 20 h at 100 mA cm−2 for OER. • Bulk silver doped Ag–NiCoSe 2 /NF has better properties than surface Ag doped products. [ABSTRACT FROM AUTHOR]

The transition metal phosphides (TMPs) with highly active and low-cost are imperative electrocatalysts for hydrogen evolution reaction (HER). In particular, metal-rich interface engineering of iron phosphide could effectively modify the active sites for HER and accelerate the charge transfer, thus achieving the promoted efficiency. Herein, we report metal-rich heterostructure of Ag-doped Fe 2 P shell attached to FeS core on Fe foams (FeS/Fe 2 P–Ag@IF) for HER, which are synthesized by a simple hydrothermal method with subsequent low-temperature phosphorization. Notably, the phosphorization process simultaneously achieves the partial conversion of FeS to Fe 2 P, and complete reduction of Ag 2 S to Ag. Furthermore, the metal-rich structure of Fe 2 P increases the active sites for hydrogen adsorption, which consequently contributes to hydrogen evolution. Simultaneously, the successful doping of metallic Ag enhanced the electroconductivity and the stability of the electrocatalyst. Benefiting from the ternary synergistic effect at FeS/Fe 2 P–Ag@IF and metallic Ag doping, the optimal Ag-doped FeS/Fe 2 P electrocatalyst exhibits a low overpotential of 214.9 mV at 100 mA cm−2, even surviving at this large current density with long-term stability. This promising strategy involving metallic Ag doping may be a suitable option for the development of iron-based metal-rich phosphides heterostructured for HER. [Display omitted] • Phosphorylation process converts FeS partially to Fe 2 P and Ag 2 S completely to Ag. • The metal-rich structure of Fe 2 P increases the active sites for hydrogen adsorption. • Ag doping effectively modulates the electronic structure and improves stability. • Strong electronic interactions of metal-rich Ag-doped FeS/Fe 2 P enhance the HER. [ABSTRACT FROM AUTHOR]

[Display omitted] • Underpotential deposition (UPD)-replacement is used to obtain low-content Pt loading. • MoO 2 /MoS 2 heterostructure is the optimal substrate for the dispersion of Pt. • Pt@MoO 2 /MoS 2 with ultrathin Pt nanocluster exhibits enhanced HER activity at wide pH. • Strong electron interaction between Pt and MoO 2 /MoS 2 contributes to HER activity. The preparation of ultrafine and uniform Pt catalysts with low content to promote hydrogen evolution reaction (HER) remains a great challenge due to the thermodynamical instability. In addition, the naturalization of water splitting and hydrogen adsorption ability also requires deliberate design. Here, we report an underpotential deposition (UPD)-replacement route for the low-content Pt loading on the MoO 2 /MoS 2 heterostructure (Pt@MoO 2 /MoS 2). The Pt@MoO 2 /MoS 2 containing uniform and ultrafine Pt nanocluster exhibits improved HER activity because the Pt and MoO 2 /MoS 2 synergistically regulate the water dissociation and hydrogen adsorption/desorption. Moreover, the strong electron interaction between Pt and MoO 2 /MoS 2 owing to the metal-support effect contributes to the acceleration of electron exchange. As verification, the Pt@MoO 2 /MoS 2 only needs 12 (alkaline) and 42 mV (acidic) to reach the current density of 10 mA cm−2, even superior to the Pt/C benchmark. The Pt@MoO 2 /MoS 2 also shows favourable long-term stability thanks to the metal-support effect. This work not only demonstrates a promising approach to fabricating high effective electrocatalyst by the complementation of the adsorption ability of intermediates, but it also provides a universal method for the preparation of single-, bi- and multimetallic cluster catalysts for series of reactions. [ABSTRACT FROM AUTHOR]

Laser etching process of aluminum thin film on polyimide substrate was simulated by the finite element analysis software ANSYS to study the etching results. Theoretical etching profiles of aluminum thin film with different laser parameters were obtained from the simulation, which is in good agreement with experimental results observed by SEM, it shows that a best etching result can be obtained and it corresponded to a set of reasonable parameters. By optimizing such laser etching parameters as laser power and beam scanning velocity, etc., aluminum thin film could be etched ideally without damaging the polyimide substrate. Therefore, the simulation results can be taken as a guide for determination of practical laser etching parameters in order to obtain ideal etching patterns. [ABSTRACT FROM AUTHOR]

An artificial intelligence (AI) assisted hyperspectral microscopic imaging (HMI) method was successfully developed to differentiate five common foodborne pathogens simultaneously. HMI is extremely powerful for characterizing living cells, with every pixel of the cell region containing abundant spectral information. Three regions of interest (ROIs), including the whole-cell ROI, boundary ROI (outer membrane of cells), and center ROI (inner area of cells) were investigated to assess their classification performance. An artificial recurrent neural network named the long-short term memory (LSTM) network was proposed and optimized to directly process the spectra acquired from different ROIs. Compared to principal component analysis (PCA) based classifiers such as latent discriminant analysis (PCA-LDA, 66.0%), the k-nearest neighbors (PCA-KNN, 74.0%), and the support vector machine (PCA-SVM, 85.0%), our AI-based classifier achieved the highest accuracy of 92.9% for the center ROI dataset. Furthermore, AI-assisted HMI is capable of predicting spectra instantly, making it an efficient tool for foodborne pathogen identification. [Display omitted] • AI assisted HMI method was developed to differentiate common foodborne pathogens. • Different ROIs for spectral extraction were investigated in classification task. • LSTM network can facilitate the classification of different foodborne bacteria. [ABSTRACT FROM AUTHOR]