Alkaline water splitting, especially anion-exchange-membrane based water electrolysis, is an attractive way for low-cost and scalable H
2
production. Green electricity-driven alkaline water ...electrolysis requires that highly-efficient electrocatalysts be developed to further decrease the barriers of two half reactions - the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Various strategies have been exploited to date, among which atomic heterointerface engineering is the most promising strategy to overcome the intrinsic activity limitation of electrocatalysts. In this review, we thoroughly summarize the recent progress of atomic heterointerface engineering to improve the activity of electrocatalysts. The origin and rationale of the sluggish kinetics of the alkaline HER and OER are first introduced. Subsequently, the synergistic effects (ensemble effect and electron effect) of atomic heterointerface engineering to overcome the activity limitation are elaborated, in which the ensemble effect is helpful in optimizing the reaction pathways with enhanced reaction kinetics by creating a favorable heterointerface and the electron effect can balance the adsorption energies of reaction intermediates by coupling their electronic configurations. And then the rational design of the targeted electrocatalysts is concluded based on the heterointerface constituents and characteristics. At the end, some outlooks about the future development direction for optimizing and maximizing the interfacial active sites in the electrocatalysts are proposed.
This review summarizes the recent progress of atomic heterointerface engineering to overcome the activity limitation of electrocatalysts for water splitting and elaborates its electron effect and ensemble effect,
etc.
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•Rapid low-temperature synthesis of hollow CuS0.55 nanoparticles has been shown.•The hollow nanostructure greatly improves electrochemically active surface area.•The rich Cu sites ...show strong adsorption ability to targeted OOH∗ intermediates.•An ultralow overpotential is required for water oxidation in alkaline media.
Developing low-cost and binder-free Cu-based electrocatalysts for high-performance oxygen evolution reactions (OER) is of great importance to promote their practical applications. Herein, we demonstrate the low-temperature and rapid synthesis of hollow CuS0.55 nanoparticles on a Cu foam as highly active OER electrocatalysts through an anodic oxidation electrodeposition technique. The large electrochemically active surface area and strong adsorption ability of Cu sites to targeted OOH∗ intermediates are beneficial for enhancing catalytic properties. As a consequence, the hollow CuS0.55 nanoparticles exhibit an ultralow overpotential of 386 mV to achieve a high current density of 100 mA cm−2 in alkaline media with a very small Tafel slope of 33 mV dec−1, which is among the best reported for Cu-based electrocatalysts. The turnover frequency (TOF) is approximately 6 times higher than those of the corresponding CuS0.57 and CuO catalysts. This work provides a simple and feasible approach that can be scaled up easily to construct low-cost and efficient Cu-based OER electrocatalysts.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tailoring valence electron delocalization of transition metal center is of importance to achieve highly-active electrocatalysts for oxygen evolution reaction (OER). Herein, we demonstrate a “poor ...sulfur” route to synthesize surface electron-deficient Co9S8 nanoarrays, where the binding energy (BE) of Co metal center is considerably higher than all reported Co9S8-based electrocatalysts. The resulting Co9S8 electrocatalysts only require the overpotentials (η) of 265 and 326 mV at 10 and 100 mA cm−2 with a low Tafel slope of 56 mV dec−1 and a 60 h-lasting stability in alkaline media. The OER kinetics are greatly expedited with a low reaction activation energy of 27.9 kJ mol−1 as well as abundant OOH∗ key intermediates (24%), thus exhibiting excellent catalytic performances. The surface electron-deficient engineering gives an available strategy to improve the catalytic activity of other advanced non-noble electrocatalysts.
The Co9S8 nanoarrays with high surface electron deficiency exhibit a low reaction activated energy and enhanced intermediate adsorption as OER electrocatalysts, thus surpassing the commercial benchmarks and most of the reported Co9S8-based materials in alkaline media. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
High nickel content layered cathodes, represented by NCM (LiNixCoyMnzO2, x + y + z = 1), are now widely employed in the market of electric vehicles, owing to their high energy density. With the ...gradual increase of nickel content and capacity, the issues on cycling life and safety become more serious. In this review, various strategies for improving the performance of high nickel NCM are summarized on the aspects of surface coating, ionic doping, and single‐crystal NCM. The coating strategy was separately described according to the physical property of coating species, including inert material coating, Li+‐conductor coating, electronic conductor coating, and mixed conductor coating. These coating species help to suppress the interfacial oxidation of electrolytes by NCM, improving the cycling life and safety. The elemental doping in the crystal lattice of NCM is then presented in the aspects of cation, anion, and mixed‐ion doping, which are beneficial to stabilize the layered structure during charge–discharge and so promote the electrochemical performance. In quite recent years, the strategy of single‐crystal NCM was demonstrated to be a promising pathway, owing to the dramatically reduced surface area and grain boundary. Finally, the remaining unsolved challenges and future strategies for further development of NCM cathode materials are outlined.
The high nickel NCM is currently the most dominant cathode material in high‐energy‐density batteries, but faces the challenges of interfacial reactions, structure deterioration, and safety issues; this review summarized the typical solving strategies for addressing these issues on the aspects of surface coating, lattice doping, and single crystallization, and discussed the corresponding function mechanisms and the remaining problems.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Recently, extensive research efforts have been dedicated to view-based 3D object retrieval, owing to its advantage of using a set of 2D images to represent 3D objects. Some existing image processing ...technologies can be employed. In this paper, we adopt Bag-of-Words for view-based 3D object retrieval. Instead of SIFT, DSP-SIFT is extracted from all images as object features. Moreover, two codebooks of the same size are generated by approximate k-means. Then, we combine two codebooks to correct the quantization artifacts and improve recall. Bayes merging is applied to address the codebook correlation (overlapping among different vocabularies) and to provide the benefit of high recall. Moreover, Approximate Nearest Neighbor (ANN) is used to quantization. Experimental results on ETH-80 datasets show that our method improves the performance significantly compared with the state-of-the-art approaches.
The current work demonstrates the fabrication of kaolin supported Au nanoparticles (Au NPs-kaolin) mediated by Thymbra spicata extract as green reductant and capping agent without any toxic reagent. ...Physicochemical characteristics of the said nanocomposite were elucidated by field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, elemental mapping, X-ray diffraction and inductively coupled plasma techniques. The figures of the TEM display the black dots signifying Au NPs being dispersed over the kaolin surface. Size of spherical Au NPs are around 10-15 nm. In the in vivo, we established a rat calvaria defect model using a combination of collagen scaffold and nanoparticle. The experimental group was divided into three classifications: control, collagen matrix and nanoparticle with collagen. Histological analyses showed that nanoparticle increased bone formation activity when used in conjunction with collagen matrix. In the nanoparticle group, grafted materials were still present until 12 weeks after treatment, as evidenced by foreign body reactions showing multinucleated giant cells in chronic inflammatory vascular connective tissue. Other results revealed that the nanoparticle increased bone formation activity when used with collagen matrix. All groups showed almost the same histological findings until 7 weeks. In the experimental groups, new bone formation activity was found continuously up to 12 weeks.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Pre-evaluating scientific paper quality aids in alleviating peer review pressure and fostering scientific advancement. Although prior studies have identified numerous quality-related features, their ...effectiveness and representativeness of paper content remain to be comprehensively investigated. Addressing this issue, we propose a content-based interpretable method for pre-evaluating the quality of scientific papers. Firstly, we define quality attributes of computer science (CS) papers as integrity, clarity, novelty, and significance, based on peer review criteria from 11 top-tier CS conferences. We formulate the problem as two classification tasks: Accepted/Disputed/Rejected (ADR) and Accepted/Rejected (AR). Subsequently, we construct fine-grained features from metadata and knowledge entity networks, including text structure, readability, references, citations, semantic novelty, and network structure. We empirically evaluate our method using the ICLR paper dataset, achieving optimal performance with the Random Forest model, yielding F1 scores of 0.715 and 0.762 for the two tasks, respectively. Through feature analysis and case studies employing SHAP interpretable methods, we demonstrate that the proposed features enhance the performance of machine learning models in scientific paper quality evaluation, offering interpretable evidence for model decisions.
•Define four criteria for quality evaluation of scientific papers: integrity, clarity, novelty, and significance.•Propose a framework for quality evaluation of scientific papers based on coarse features and knowledge entity network.•An effective algorithm for measuring the novelty and significance of scientific papers based on knowledge entity networks.•Create and release a rigorous dataset, which could serve as the gold standard for quality evaluation of scientific papers.•Conduct extensive experiments to validate the effectiveness of the proposed framework.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The investigation of the in-plane shear behavior of prepreg is crucial for understanding the generation of wrinkles of preforms in advanced composite manufacturing processes, such as automated fiber ...placement and thermoforming. Despite this significance, there is currently no standardized test method for characterizing uncured unidirectional (UD) prepreg. This paper introduces a ±45° off-axis tensile test designed to assess the in-plane shear behavior of UD carbon fiber-reinforced epoxy prepreg (CF/epoxy). Digital image correlation (DIC) was employed to quantitatively track the strains in three dimensions and the shear angle evolution during the stretching process. The influences of the temperature and stretching rate on the in-plane shear behavior of the prepreg were further investigated. The results reveal that four shear characteristic zones and wrinkling behaviors are clearly distinguished. The actual in-plane shear angle is significantly lower than the theoretical value due to fiber constraints from both the in-plane and out-of-plane aspects. When the off-axis tensile displacement (d) is less than 15.6 mm, the ±45° specimens primarily exhibit macroscale in-plane shear behavior, induced by interlaminar interface shear between the +45° ply and −45° ply at the mesoscale. The shear angle increases linearly with the d. However, when d > 15.6 mm, fiber squeezing and wrinkling begin to occur. When d > 29 mm, the in-plane shear disappears in the completely sheared zone (A). The reduction in the resin viscosity of the CF/epoxy prepreg caused by increased temperature is identified as the primary factor in lowering the in-plane shear force resistance, followed by the effect of the increasing resin curing degree. Higher shear rates can lead to a substantial increase in shear forces, eventually causing cracking failure in the prepreg. The findings demonstrate the feasibility of the test method for predicting and extracting uncured prepreg in-plane shear behaviors and the strain-rate and temperature dependency of the material response.
To discover a novel lead structure for antiphytopathogenic fungus agent, a series of (R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfonohydrazide moiety were designed and ...synthesized. They were determined by melting points,
1
H NMR,
13
C NMR, and elemental analysis (EA). The biological activity results revealed that these title compounds possessed antifungal and insecticidal activities. Some title compounds against Alternaria solani, Physalospora piricola, Cercospora arachidicola, Phytophthora capsici, Fusarium graminearum, and Sclerotinia sclerotiorum displayed moderate to good antifungal activities at 50 mg/L, especially, compounds
6b
and
6p
displayed good and broad-spectrum antifungal activities. The structure activity relationships were discussed. A 3D-QSAR model was established based on the antifungal activity against Phytophthora capsici, indicating that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. Hence, structure optimization based on the CoMSIA model was performed to find compound
6p
with excellent activity against Phytophthora capsici, and the EC
50
values of compound
6p
were comparable to those of chlorothalonil. Furthermore, the insecticidal activity of compound
6p
against Culex pipiens larvae at 1 mg/L was considerable to that of chlorantraniliprole. Therefore, compound
6p
can be used as a novel lead structure for antiphytopathogenic fungus and insecticidal agent development.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In recent years, more and more people are applying Convolutional Neural Networks to the study of sound signals. The main reason is the translational invariance of convolution in time and space. ...Thereby the diversity of the sound signal can be overcome. However, in terms of sound direction recognition, there are also problems such as a microphone matrix being too large, and feature selection. This paper proposes a sound direction recognition using a simulated human head with microphones at both ears. Theoretically, the two microphones cannot distinguish the front and rear directions. However, we use the original data of the two channels as the input of the convolutional neural network, and the resolution effect can reach more than 0.9. For comparison, we also chose the delay feature (GCC) for sound direction recognition. Finally, we also conducted experiments that used probability distributions to identify more directions.
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