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It is common to use heat treatment process to control the microstructure of additive manufacturing parts and improve the mechanical properties. However, there are few reports about the control of microstructure properties of WAAM hybrid inter-layer hammering fabricated parts by heat treatment. In this study, the effect of annealing on microstructure and mechanical properties of inter-layer hammering hybrid wire arc additively manufactured aluminum alloy was studied. The ratio variation of fine grain (FG) and coarse grain (CG) regions, grain size and dislocations were analyzed, and the strength-plasticity mechanism was revealed. The results shown that with the increase of annealing temperature, the ratio of FG and CG region changed from 4:1–1:5, grain growth and recrystallization happened in FG and CG regions, respectively, dislocations mostly retained in FG region and released in CG region. With the introduction of annealing and the increase of annealing temperature, the strength of hybrid manufactured samples gradually weakened while the plasticity first improved and then reduced. The best tensile properties of ultimate tensile stress 366 MPa and elongation 29.2% were achieved at 180 °C annealing. Compared with as-deposited sample, the synergistic enhancement of strength and plasticity in annealed samples is owing to dislocation strengthening, grain refinement, and heterogeneous structural strengthening. Compared with hammered sample, the strength retained and significant improved in plasticity of annealed sample, owing to dislocation released, grain refinement and heterogeneous structural. • The variation ratios of FG and CG regions were studied. • Superior strength-ductility was achieved with annealing treatment. • The effect of annealing on strengthening mechanism was revealed. [ABSTRACT FROM AUTHOR]

• The chemical coverage of most human protein families is poor. • We extracted the druggability of proteins bound to drug-like ligands in the PDB. • WDR-containing proteins represent a large, druggable, disease-associated family. • We generated a list of 46 druggable domains representing 3440 human proteins. International efforts are underway to develop chemical probes for specific protein families, and a 'Target 2035' call to expand these efforts towards a comprehensive chemical coverage of the druggable human genome was recently announced. But what is the druggable genome? Here, we systematically review structures of proteins bound to drug-like ligands available from the Protein Data Bank (PDB) and use ligand desolvation upon binding as a druggability metric to draw a landscape of the human druggable genome. The vast majority of druggable protein families, including some highly populated and disease-associated families, are almost orphan of small-molecule ligands. We propose a list of 46 druggable domains representing 3440 human proteins that could be the focus of large chemical probe discovery efforts. [ABSTRACT FROM AUTHOR]

With the promotion of lightweight and green ships, shipbuilding materials tend to have the properties of high strength, high toughness, corrosion resistance and so on. With the advantages of not corroded by sea water and high-hardness, titanium alloy is gradually widely used. Many complex curved plates are needed in the construction process of ships. From the perspective of economic benefits, line heating is a common technology for the forming of large size curved hull plate. Titanium alloy has high strength and small deformation coefficient, and it is not easy to deform by single heating. At present, there is a lack of research on overlapping line heating of marine titanium alloy curved plate. Therefore, TA5 titanium alloy is taken as the research object in this article. According to the characteristics of titanium alloy, the numerical calculation model of single heating line is established based on the theory of thermoelastic shaping. Compared with the results of real curved plate, the feasibility of the numerical calculation model of low carbon steel is verified. Furthermore, the feasibility of the numerical calculation model of titanium alloy is verified. Based on the characteristics of titanium alloy line heating, a numerical calculation model of overlapping line heating of titanium alloy curved plate is established, the temperature field and deformation field are compared. The influence factors of line heating of titanium alloy are analyzed, and the influence of geometric parameters and forming parameters on shrinkage and deflection is researched. This research can provide reference for the construction of lightweight and green ships, and also for the curved plate forming of the equipment in the fields of deep-sea exploration, seawater desalination and sonar detection. • The numerical calculation of overlapping heating for titanium alloy line heating curved plate formingis realized. • In the process of overlapping heating, the temperature field and deformation field are output and compared in real time. • According to the actual situation of the plate and the experience of the workers, the number of overlapping heating is set. • Using APDL, set constraints to improve the accuracy of numerical simulation results. [ABSTRACT FROM AUTHOR]

Nanostructured transition-metal phosphides (TMPs) have recently emerged as a new family of non-noble-metal catalysts to drive water splitting due to their unique electronic and redox properties. However, most progress focused on developing mono-metal phosphide nanostructures. In this work, a facile template-based method and low-temperature phosphorization process are proposed to fabricate self-supported Ni-based bimetallic phosphide encapsulated in amorphous carbon by using metal-organic framework (MOF) as the precursor and three-dimensional nickel foam (NF) as the support, which is termed as Ni 2 P-Co 2 P@C/NF. This composite demonstrates remarkable electrocatalytic activities towards both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline electrolyte (1 M KOH, pH 13.6), affording low overpotentials of 290 and 167 mV to deliver the current density of 50 mA cm−2 for OER and HER, respectively, preceding the majority of recently reported MOFs-derived TMPs. This excellent performance is considered as the results of its large catalytic surface area, concerted synergy from composited structure as well as the increased electrical conductivity. [ABSTRACT FROM AUTHOR]

• The biodiversity benefit of tree mixtures is seldom assessed in production settings. • We studied early-stage commercial Eucalyptu s tree-mixtures in southern China. • We assessed the effectiveness of tree mixtures in enhancing avian diversity. • Tree mixtures outperformed monocultures modestly in breeding season only. • Species benefiting were linked to understory and mature forests. Commercial timber plantations, particularly monocultures, have limited capacity to support biodiversity. A widely promoted approach to enhance this capacity is the diversification of monocultures into tree mixtures, by adding "secondary" timber species while retaining the production focus on the monoculture species. However, the presumed biodiversity benefits of tree mixtures are yet to be robustly tested, because current evidence predominantly comes from mixed plantations in the general sense, which are often not under active production or differ from monocultures in other important ways. To address this gap, we assess the effectiveness of early-stage tree mixtures in enhancing the avian diversity of Eucalyptus monocultures in southern China, which is the country's most important timber production region and has been pioneering tree mixtures in large trials over the past decade. During the avian breeding and non-breeding seasons in 2021, we conducted rigorous surveys to compare the avian diversity of Eucalyptus monocultures and their tree mixtures involving slow-growing native species, against the reference baseline of mature native forests. We found that tree mixtures exhibited modest advantages over monocultures during the breeding season, and both plantation types had notable shortfalls relative to mature native forests. We additionally found that tree mixtures tended to benefit species that foraged in the medium–low strata, consumed diets of higher trophic levels, and depended more on mature forest habitat. We conclude that the biodiversity benefits of early-stage commercial tree mixtures were rather limited and more modest than typically assumed, highlighting the importance of studying tree mixtures in real-world production settings. Our study also underscores the conservation importance of protecting existing mature native forests. [ABSTRACT FROM AUTHOR]

The characteristics and performance of natural albite as a solid basic catalyst was investigated in the transesterification of rapeseed oil to produce biodiesel. TEM images and the BET results indicate that natural albite has a small surface area (0.1601 m 2 ·g −1 ) with non-porous structure. XRD analysis indicated that the catalyst comprises two crystalline phases: quartz (SiO 2 ) and albite (NaAlSi 3 O 8 ), at proportions of 27% and 73%, respectively. Crystal structure analysis showed that the basic sites of NaAlSi 3 O 8 are bridge oxygens that connect silicon-oxygen tetrahedron [SiO 4 ] and aluminium-oxygen tetrahedron [AlO 4 ] or [SiO 4 ]. The basicity of all bridge oxygens under the same chemical environment is almost identical, as identified by XPS analysis. The catalyst has high catalytic activity and good water resistance, and it also immunes from the free fatty acids (FFA) in raw materials. High fatty acid methyl ester (FAME) conversion of 95.15% and 97.42% was obtained with rapeseed oil and mixture oils (rapeseed oil with 10 wt% oleic acid) under the optimized conditions of 10 wt% catalyst dosage, methanol/oil molar ratio 12:1, at 200 °C for 8 h. Furthermore, it remained above 94.33% and 94.53% in rapeseed oil and mixture oil, respectively, after reusing the catalyst for five cycles without catalyst compensation. [ABSTRACT FROM AUTHOR]

Ca 2 MgSi 2 O 7 has been investigated in the transesterification of rapeseed oil with a view to determining its viability as a solid base catalyst for use in biodiesel synthesis. This catalyst exhibited both high catalytic activity and reusability, giving a fatty acid methyl ester (FAME) conversion of 99% when the reaction was conducted with 20 wt% catalyst and a methanol/oil molar ratio of 10:1 at 190 °C over 6 h. The FAME conversion remained >85% after 16 cycles without catalyst compensation. BET test illustrates that Ca 2 MgSi 2 O 7 has a narrow pore size distribution centred at 5.0 nm. Transesterification takes place on the catalyst surface, the basic characteristics or basicity of the catalyst decide greatly catalytic activity. CO 2 -TPD analysis showed that the total number of basic sites of åkermanite is 0.8822 mmol·g −1 . This includes three different oxygen anions exhibiting different chemical environments on the catalyst surface. The basic strength of oxygen anions increased in the order O2 < O3 < O1, which were identified by XPS. In addition, the excellent reusability of the catalyst was associated with the presence of stable [MgO 4 ] and [CaO 8 ] structures. These results suggest that Ca 2 MgSi 2 O 7 is a promising catalyst for biodiesel synthesis. [ABSTRACT FROM AUTHOR]

A novel solid base catalyst derived from gasified straw slag for producing biodiesel was prepared by simple pulverization and sieving. This catalyst exhibited high stability, low leaching of the catalytic species, and good catalytic activity, caused by high-temperature melting in the biomass gasifier. SiO 2 , CaO, K 2 O, MgO, FeO, and Al 2 O 3 were the common constituents (calculated as oxides) as per XRF analysis and EA. XRD and TEM-EDS analysis indicated that the catalyst comprises three crystallites: quartz, leucite, and åkermanite. The catalyst was strongly basic with a basic site concentration of 0.3974 mmol⋅g −1 , including strongly basic low-coordination oxygen anions, moderately basic OH groups, and metal–oxygen pairs, as identified by CO 2 -TPD and IR. TGA results indicated that the catalyst is thermally stable up to 400 °C, which is greater than the typical reaction temperature. BET analysis results indicated that the slag exhibits a broad pore distribution with pore diameters of 5–15 and 45–75 nm. The catalyst exhibited high catalytic activity and stability, exhibiting a fatty acid methyl ester (FAME) conversion of 95% for transesterification conducted at 200 °C for 8 h with a catalyst dose of 20% and a methanol–oil molar ratio of 12:1. The FAME conversion remained greater than 85% even after reusing the catalyst for 33 reactions without any appreciable loss of catalytic activity. Small amounts of K and Mg (<10 ppm) leached into the product from the catalyst. These results indicated that the gasified straw slag catalyst demonstrates promise for producing biodiesel. [ABSTRACT FROM AUTHOR]

Digital watermarking is of critical importance in multimedia copyright protection. However, with the development of Internet technologies, the combined attacks of complex environments challenge to the robustness of traditional digital watermarking schemes. In order to tackle this problem, a robust periodic blind watermarking scheme based on sub-block mapping and block encryption is proposed in this paper to enhance robustness under combined attacks. Concretely, a watermark is encoded by the periodic encoding method to raise the fault tolerance rate. Then a block encryption technique is designed to encrypt periodic sub-blocks by utilizing different encoding methods to maintain the security of copyright information. To achieve high image quality, this scheme employs a sub-block mapping mechanism to map the encrypted periodic watermark into a smaller watermark to minimize the visual difference between host image and watermarked image. Finally, an improved Singular Value Decomposition (SVD) is conducted to embed a quaternary watermark that can extend to a gray-scale watermark. Experimental results demonstrate that the proposed watermarking scheme has good visual quality of watermarked images and is robust to image processing attacks, especially in cropping, scaling and combined attacks, which is better than other watermarking schemes. [ABSTRACT FROM AUTHOR]

Brivaracetam is an effective third-generation antiepileptic drug, and its two chiral centers are a major challenge for designing an inexpensive large-scale synthesis process. Enzymatic asymmetric reduction offers an alternative biotransformation method for reducing 2-(5H)-furanone-4-propyl (3a) to (R)-4-propyldihydrofuran-2(3 H)-one (3b), which is a key intermediate in synthesizing brivaracetam. However, no enzymes have been reported to catalyze this reaction with both high activity and stereoselectivity. In this study, fourteen ene-reductases were compared, and the old yellow enzyme OYE2 was identified as having strict stereoselectivity but unsatisfactory activity. Through evaluations with structurally similar substrates and alanine-screening methods, two key residues were identified, T37 and Y82, playing critical roles in catalytic activity. The hydrogenation activity of mutants Y82W and T37C increased by 2.97 and 7.13 times, respectively. Molecular dynamics simulation indicates that mutant Y82W might shorten the distance between the electron acceptor and donor, while T37A might decrease the redox potential of FMN and then accelerate hydrogen transfer. These results indicate that tuning the redox potential properties of FMN is an important consideration for engineering FMN-dependent oxidoreductases. During the gram-scale synthesis of 3b , T37C exhibited excellent stereoselectivity (>99 % ee) and conversion (>99 %), laying a foundation for a simple one-step route in producing the chiral precursor brivaracetam. [Display omitted] • A brivaracetam precursor was synthesized by old yellow enzyme OYE2. • Two key points, Thr37 and Tyr82, were identified with enhanced reduction activities. • Mutation in Tyr82 site could shorten the distance between electron donor and acceptor. • Mutation in Thr37 site could decrease the redox potential of flavin mononucleotide. [ABSTRACT FROM AUTHOR]

Sustainable development is a global issue requiring supply chain members to invest in sustainable technology to protect the environment. Manufacturers can motivate suppliers to increase sustainability investment level through various types of contracts, such as price commitment and cost-sharing contracts. In this context, we consider a two-echelon sustainable supply chain with a manufacturer and a supplier. We use price commitment as basis to study several scenarios, such as centralized/decentralized decision system, pure price commitment contract, commitment to wholesale price and cost-sharing contract, and two-part tariff contract. Accordingly, we mainly discuss if these contracts can improve the sustainability investment level of suppliers and if Pareto improvement can be achieved. Results show that the pure price commitment contract can neither improve suppliers sustainability investment level nor coordinate the supply chain. By contrast, with a combination on price and sharing ratio, commitment to wholesale price with cost sharing is beneficial in enhancing suppliers sustainability investment level and can achieve the Pareto improvement in profit for supply chain members. Lastly, numerical results reveal that main contract parameters, such as basic wholesale price, sensitivity of wholesale price to sustainability investment level, and coefficient of sustainability effect, greatly influence the profits of supply chain members. The commitment to wholesale price with cost-sharing contract can likewise achieve the Pareto improvement in a certain condition. [ABSTRACT FROM AUTHOR]

MgO–C refractories are employed as linings for high–temperature containers where they are susceptible to thermal shock and oxidation. In this work, the oxidation behavior of low–carbon MgO–C refractories under thermal cycling was investigated for the first time, and the potential utilization of TiB 2 –BN–AlN (TBA) industrial waste as an additive was also investigated. The results showed that the traditional antioxidant Al was basically ineffective under the condition of thermal cycling; however, the incorporation of TBA industrial waste effectively maintains exceptional oxidation resistance, regardless of thermal cycling. This can be attributed to its capacity to seal the porosity, prevent oxygen intrusion, and absorb elastic strain energy while reducing stress. Additionally, when exposed to an oxidizing atmosphere, MgO–C refractories containing only TBA industrial waste exhibit a low thermal expansion coefficient. [ABSTRACT FROM AUTHOR]

Abstract A hierarchical CoS shelled Cu 2 S nanorods material grown directly on copper foam (denoted as Cu 2 S NRs@CoS/CF) was prepared for the first time and used as the bifunctional electrocatalyst for both OER and HER in 1 M KOH solution. Resulting from the substrate-integrated synthesis, the highly open spaces and the synergistic effects between Cu 2 S and CoS active components, the as-obtained core-shell heterostructure and its derivative behaves as a remarkable active bifunctional electrocatalyst towards both water oxidation and hydrogen evolution reaction in 1 M KOH solution (pH 13.7), which only need low overpotentials of 275 and 235 mV to deliver the current density of 50 mA cm−2 with Tafel slopes of 54 and 121 mV dec−1 for OER and HER, respectively, rivalling the catalytic efficiency of most published non-noble metal catalysts. Furthermore, the fabrication strategy presented here is facile and economical which might offer some insights for fabricating other novel water splitting catalysts with high activity. Highlights • A hierarchical Cu 2 S NRs@CoS core-shell structure was obtained by a room-temperature sulfurization method. • The hierarchically 3D configuration provides a large number of catalytic active sites. • The as-prepared electrode acted as bifunctional catalyst toward electrochemical water splitting. • The as-prepared electrode shows both notable OER and HER activity in alkaline media. • The synergistic effect between Cu 2 S core and CoS shell is conductive to promote the catalytic activity. [ABSTRACT FROM AUTHOR]

Four kinds of imidazolium ionic liquids (ILs) were employed to catalyze the transesterification reaction of rapeseed oil. The effects of molar ratio of methanol to rapeseed oil, catalyst dosage, reaction temperature, and reaction time, and the deactivation of water on catalytic activity were explored. The results showed that imidazolium ILs with long alkyl chains and sulfonated groups exhibited the best catalytic activities due to their strong Brønsted acidity. The catalytic activity was depend on the SO 3 H group in the cation, not the anion HSO 4 − . Water molecules competed with the anion to bind with the protons of the imidazolium cation. This results in the disruption of the structure of ILs, leading to deactivation; increasing the reaction temperature could alleviate this negative effect of water. The yield of fatty acid methyl ester (FAME) remained constant (∼85%) at 130 °C, when the water content increased from 1 wt% to 5 wt%. The highest yield of FAME for the catalyst 1-butylsulfonate-3-methyl imidazolium hydrogen sulfate ([BSO 3 HMIM][HSO 4 ]) could reach 100% under optimum conditions. [ABSTRACT FROM AUTHOR]

The use of boron–containing additives often raises concerns when exposed to high temperatures. In this study, the high temperature stress–strain behavior and degradation mechanism of low–carbon MgO–C refractories containing TiB 2 –BN–AlN waste were investigated. Stress–strain curve, peak axial stress, Young's modulus, cohesion, and residual strength ratio after thermal shock tests were thoroughly analyzed. The findings suggest that the mechanical properties of refractories remain unimpaired within the temperature range of 900–1100 ℃, and can even be enhanced through the synergistic effect of TiB 2 –BN–AlN waste and Al powder. The optimized axial stress increased from 55.0 to 62.0 MPa at 1100 ℃, while the cohesion increased from 10.0 to 13.8 MPa, respectively. The observed enhancement can be primarily attributed to the effective healing of pores and cracks, reduction in oxidation, and improved material cohesion. However, the excessive incorporation of boron–containing waste may compromise the performance of refractories, leading to instability or degradation. [ABSTRACT FROM AUTHOR]

• On-package colorimetric sensing label was developed for fish freshness. • Label was based on bromocresol green indicator and sol-gel matrix layer. • A Hue Saturation Value model was used to correlate the response of sensing label. • Three kinds of fish fillets showed intense color change during the spoilage trial. Fish freshness monitoring is important for consumers. This study aims to develop an colorimetric sensing label based on bromocresol green (BCG) and a sol-gel matrix layer coated onto filter paper to monitor fish freshness. Characterization results showed that the sol-gel layer was successfully coated, and the coating yield was 14.25%. The fish freshness could be detected clearly by the naked eye as the color of the sensing label changed. A Hue Saturation Value (HSV) model was used to correlate the response of the sensing label to the freshness of fish samples. Hue (H) values showed a linear response to the total volatile basic nitrogen (TVB-N) concentration in the range of 16.4–23.11 mg/100 g at room temperature, and in the range of 9.28–24.12 mg/100 g at a chilled temperature. The sensing label was applied to other types of fish, and showed an intense color change during the spoilage trial. [ABSTRACT FROM AUTHOR]

A series of pore-broadened Al-SBA-15 samples were synthesized using a direct hydrothermal method. The effects of aluminum incorporation, assembling temperature, and co-solvent (1,3,5-trimethylbenzene (TMB)) content were investigated by low-angle XRD, N 2 adsorption and desorption isotherm analysis, SEM, TEM, NH 3 -TPD, FTIR, pyridine-IR, and 27 Al NMR. The results indicated that aluminum incorporation (Si/Al ratio = 10) increased the pore size of SBA-15 from 5.66 to 10.13 nm. A small pore size of 6.55 nm was observed at a low assembling temperature of 30 °C, attributing to the inadequate stretching of the molecular template. An increased pore size of 8.45 nm was obtained at an assembling temperature of 60 °C because of the partial hydrophobization of the hydrophilic groups, whereas a high temperature of 70 °C resulted in the generation of least ordered pores. The hydrophobic co-solvent TMB showed a significant broadening level as a result of its effective fusion into the hydrophobic micelle cores. A highly ordered pore framework with a pore size of 18 nm was obtained at a TMB/P 123 ratio of 0.25, which was found to be optimum. More or less TMB led to the generation of mesocellular silica-aluminum foams with a complete loss of regularity. The 27 Al NMR results showed that aluminum was mostly tetrahedrally coordinated. The NH 3 -TPD and pyridine-IR detection results indicated that a number of weak and medium acid sites (as Bronsted and Lewis acid sites) existed in Al-SBA-15 pore-broadened by TMB. [ABSTRACT FROM AUTHOR]

This paper proposes a distinct multiscale shape context (MSC) method for isometric 3D shape description and retrieval. For each feature point, a MSC descriptor is devised to capture the multiple spatial information on the basis of the intrinsic shape context, which is advantageous in solving the domain offset deficiency for intra-class shapes. Different from the traditional shape context method, the MSC descriptor is built based on the charts without angular bins and the shape distributions in local domains, which makes it not only simple but also efficient. To reduce the cost of shape representation, we detect a sparse set of feature points and design an improved bags-of-word model to encode the MSC descriptors. For retrieval improvement, an efficient while robust re-ranking algorithm by metric mapping is designed to alleviate the errors of the feature space. Finally, the experimental results have demonstrated significant performance gains on two public benchmarks. [ABSTRACT FROM AUTHOR]