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Photocatalytic antimicrobial is a promising advanced oxidation antibacterial technology that can utilize solar energy to achieve antibacterial function. However, due to the influence of diurnal variation, photocatalytic antimicrobials cannot maintain a continuous antibacterial effect in practical applications. Herein, a TiO2 fiber with CuO particle (TiO2/CuO) pn-type heterojunction with dual inactivation of Escherichia coli has been designed and prepared for water treatment. The formation of pn heterojunction and its high efficiency of charge separation and transfer were confirmed through HRTEM, FESEM, UV–Vis and photoelectrochemical tests, while the charge separation process of the heterojunction under visible-light irradiation was systematically investigated. The results showed that the antimicrobial rate of TiO2/CuO composites was 64.7% at 10 min under dark conditions. In contrast, under light exposure, the antibacterial rate could reach 96.2% for 10 min and 100% for 20 min. This research holds promise for advancing the construction of pn heterojunctions and provides a novel insight into reducing the dependence of photocatalytic antimicrobials on light. [ABSTRACT FROM AUTHOR]

The accelerated growth of 3D printing technologies has revolutionized the potential of ceramic materials, offering unprecedented control over microstructures, saving labor cost, material, and process time. Stereolithography-based 3D printing has grown to fabricate advanced ceramics materials with the flexibility of mass production. 3D printing generally offers unprecedented versatility, fast-printing tangible design, custom freedom, and excellent laying accuracy. More specifically, ceramic materials offer unique mechanical properties to make them superior for various applications. A description of how digital light processing (DLP) 3D printing can play a pivotal role in fabricating oxide ceramics in terms of complex shape, material used, ceramic resin, debinding and sintering control, and theoretical background for accuracy and high resolution is presented along with their distinctive features. Within 2021–2026, the DLP printing market is expected to reach a GR of 5.9%. The current findings shed light on the potential of DLP printing open windows in ceramic materials, which is are very promising, a step forward to achieving sophisticated structures with great versatility and efficiency. This review article is devoted to ceramics and their oxides (Al2O3, ZrO2, and kaolin), non-oxides (Si3N3 and SiC), and Al2O3-reinforced ZrO2 composites, whose morphologies are elaborated in depth. Some key factors are prioritized, such as the ceramic resin, photoinitiator, monomers, and suspension, which may facilitate the scalability of the desired printing. A summary table concludes with the operating conditions, materials, and fundamental aspects of physiochemical and thermomechanical features in large-scale manufacturing. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have rapidly received increasing attention and great interest as potential materials for energy storage and catalyst fields, which is due to their unique physicochemical and electrical properties. With continuous improvements in fabrication routes, CNTs have been modified with various types of materials, opening up new perspectives for research and state-of-the-art technologies. Amorphous CNTs (aCNTs) are carbon nanostructures that are distinctively different from their well-ordered counterparts, such as single-walled and multi-walled carbon nanotubes (SWCNTs and MWCNTs, respectively), while the atoms in aCNTs are grouped in a disordered, crystalline/non-crystalline manner. Owing to their unique structure and properties, aCNTs are attractive for energy storage, catalysis, and aerospace applications. In this review, we provide an overview of the synthetic routes of aCNTs, which include chemical vapor deposition, catalytic pyrolysis, and arc discharge. Detailed morphologies of aCNTs and the systematic elucidation of tunable properties are also summarized. Finally, we discuss the future perspectives as well as associated challenges of aCNTs. With this review, we aim to encourage further research for the widespread use of aCNTs in industry. [ABSTRACT FROM AUTHOR]

In this work, a TiO2/In2S3 heterojunction film was successfully synthesized using a one-step hydrothermal method and applied in the photocathodic protection (PCP) of 304SS. The octahedral In2S3 and In2S3@TiO2 nanoparticles combined and coexisted with each other, with In2S3 quantum dots growing on the surface of TiO2 to form In2S3@TiO2 with a wrapping structure. The composite photoelectrode, which includes TiO2 with a mixed crystalline phase and In2S3, exhibited significantly enhanced PCP performance for 304SS compared with pure In2S3 and TiO2. The In2S3@TiO2/In2S3 composites with 0.3 g of P25 titanium dioxide (P25) showed the best protection performance, resulting in a cathodic shift of its OCP coupled with 304SS to −0.664 VAgCl. The electron transfer tracking results demonstrate that In2S3@TiO2/In2S3 forms a Z-scheme heterojunction structure. The enhanced PCP performance could be attributed to the synergistic effect of the mixed crystalline phase and the Z-scheme heterojunction system. The mixed crystalline phase of TiO2 provides more electrons, and these electrons are gathered at higher energy potentials in the Z-scheme system. Additionally, the built-in electric field further promotes the more effective electrons transfer from photoelectrode to the protected metals, thus, leading to enhanced photoelectrochemical cathodic protection of 304SS. [ABSTRACT FROM AUTHOR]

In this work, an oxidized g-C3N4 film was successfully synthesized using a two-step acid treatment and electrophoretic deposition method. The delocalized π-system of the oxidized g-C3N4 film was extended via an annealing treatment. We investigated the influence of hydrogen bonding reversibility and the oxidation treatment of g-C3N4 on the photoelectrochemical property and photocathodic protection for 304 stainless steel (304 SS). The resulting oxidized g-C3N4 photoelectrode with an extended π-system presents a remarkably enhanced photogenerated electron transfer capability from the photoelectrode to 304 SS (photoinduced OCP negative shift of −0.55 VAgCl) compared with oxidized g-C3N4 and protonated g-C3N4. The oxidation of g-C3N4 facilitates the formation of a porous structure and the introduction of abundant oxygen functional groups, which could promote the effective separation and transport of photogenerated electron–hole pairs. The hydrogen bonding reversibility contributes to the extension of the delocalized π-conjugation system, which could enhance light absorption efficiency. Meanwhile, the annealing treatment is beneficial for prolonging the lifetime of photoelectrons, which could reduce the recombination rate of charge carriers. In addition, to understand how the oxidation treatment and annealing treatment affect the charge transfer behavior, the electronic band structure was investigated, and we found that the oxidized g-C3N4 film with an extended π-system possesses a more negative conduction band position, which could reduce the energy barrier of the photogenerated electron transfer. [ABSTRACT FROM AUTHOR]

Summary: Chaptalisation is commonly used to ameliorate the potential alcohol of kiwi wine prior to fermentation. It can be performed either by one‐time sugaring or via multiple supplementations of sugar. However, for both approaches, their precise effects on chemical composition of kiwi wine are unclear. Thus, this study evaluated the influence of five different multi‐step chaptalisation strategies on physicochemical parameters, potentially harmful alcohols, nutritional composition and volatile compounds of kiwi wine. Results show that multi‐step chaptalisation significantly reduced total acidity and harmful alcohols of the resulting kiwi wine. Among the harmful alcohols, the greatest reduction was seen for isoamyl alcohol and isobutanol. Additionally, multi‐step chaptalisation also modified volatile profile of the kiwi wine, particularly in acetate esters (isoamyl acetate and phenethyl acetate), ethyl esters, n‐octanal and decanal. Together, our results highlight the potential of using multi‐step chaptalisation to produce 'healthier' kiwi wines with more balanced alcohol and more complexed flavour. [ABSTRACT FROM AUTHOR]

In this study, Ni35Co35Cr12.6Al7.5Ti5Mo1.68W1.39Nb0.95Ta0.47 high entropy alloy (HEA) was prepared using mechanical alloying (MA) and spark plasma sintering (SPS) based on the unique design concept of HEAs and third-generation powder superalloys. The HEA phase formation rules of the alloy system were predicted but need to be verified empirically. The microstructure and phase structure of the HEA powder were investigated at different milling times and speeds, with different process control agents, and with an HEA block sintered at different temperatures. The milling time and speed do not affect the alloying process of the powder and increasing the milling speed reduces the powder particle size. After 50 h of milling with ethanol as PCA, the powder has a dual-phase FCC+BCC structure, and stearic acid as PCA inhibits the powder alloying. When the SPS temperature reaches 950 °C, the HEA transitions from a dual-phase to a single FCC phase structure and, with increasing temperature, the mechanical properties of the alloy gradually improve. When the temperature reaches 1150 °C, the HEA has a density of 7.92 g cm−3, a relative density of 98.7%, and a hardness of 1050 HV. The fracture mechanism is one with a typical cleavage, a brittle fracture with a maximum compressive strength of 2363 MPa and no yield point. [ABSTRACT FROM AUTHOR]

Mesoporous carbon nanotubes (mCNTs) hold great promise interests, owing to their superior nano-platform properties for biomedicine. To fully utilize this potential, the toxicity and biodistribution of pristine and surface-modified mCNTs (-OH/-COOH) should preferentially be addressed. The results of cell viability suggested that pristine mCNTs induced cell death in a concentration-dependent manner. As evidence of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD), pristine mCNTs induced noticeable redox imbalance. 99mTc tracing data suggested that the cellular uptake of pristine mCNTs posed a concentrate-dependent and energy-dependent manner via macropinocytotic and clathrin-dependent pathways, and the main accumulated organs were lung, liver and spleen. With OH modification, the ROS generation, MDA deposition and SOD consumption were evidently reduced compared with the pristine mCNTs at 24/48 h high-dose exposure. With COOH modification, the modified mCNTs only showed a significant difference in SOD consumption at 24/48 h exposure, but there was no significant difference in the measurement of ROS and MDA. The internalization mechanism and organ distribution of modified mCNTs were basically invariant. Together, our study provides evidence that mCNTs and the modified mCNTs all could induce oxidative damage and thereby impair cells. 99mTc-mCNTs can effectively trace the distribution of nanotubes in vivo. [ABSTRACT FROM AUTHOR]

(Purpose/Significance). This paper aims at the problems of inaccurate recommendation effect caused by data sparseness and cold start in the traditional collaborative filtering-based book personalized recommendation algorithm. So this paper proposes a collaborative filtering recommendation algorithm which improves the similarity solution method and the filling method of missing data. (Method/Process). By considering the influence of the user's common rating book collection on the similarity calculation, the average rating value of all books is used as the threshold, and the user's common rating weight is introduced into the user's similarity calculation. As for data filling, according to the user's average rating, the basic attributes such as the age and gender of users are coded, and then Euclidean distance is initially calculated, making hierarchical clustering on users. What's more, Shope-one algorithm is used to calculate the filling value of the former m similar users，and add the weight value of the degree simultaneously to get the final filling value, so as to improve the data filling method. (Result/Conclusion). Experiments were carried out with the data set of Book-Crossing Data set through Python. The experimental results show that the improved collaborative filtering algorithm has a significantly improvement in the accuracy and quality of book recommendation. [ABSTRACT FROM AUTHOR]

In order to solve the existing problems such as non-standard size, easy deformation and inconvenient movement of the arm of dress form, a movable arm of male dress form was designed and manufactured by using forward and reverse hybrid modeling technology and rapid prototyping technology. According to the point cloud data of human arm obtained by 3D scanner, the arm model was reconstructed by Geomagic and ZBrush software. The shoulder joint connectors were designed by Solidworks software. Then the arm model engraving, joint model printing and connection piece laser cutting were realized by rapid prototyping technology. Finally, the self-made arm of dress form was compared and analyzed with the existing products in the market. The result shows that the self-made arm of dress form not only ensures the accuracy of the size, but also can simulate the basic movements of the human arm swinging back and forth and lifting up and down, which meets the requirements of mobility in sleeve design and provides technical reference for mannequin manufacturing enterprises. [ABSTRACT FROM AUTHOR]

Neutral cellulase-assisted steam distillation (NCSD) was developed to extract essential oil from Valeriana officinalis L. root, and a single-factor experiment was designed to optimize the NCSD. Chemical composition was subsequently compared between Valeriana officinalis L. root essential oil (VORO) extracted by NCSD and conventional steam distillation (SD). Results show that the highest yield of VORO extracted by NCSD was 68.09% higher than that extracted by SD. Results of antibacterial activity indicate that the two VOROs had an equally strong antibacterial activity of Bacillus subtilis, Staphylococcus aureus, and Escherichia coli with minimum inhibitory concentration (MIC) of 0.88, 1.75, and 3.50 mg/mL, respectively. Both VOROs also showed sufficiently high antioxidant and anti-dust mite abilities. The VORO concentration higher than 0.35 mg/mL was regarded as an A-grade dust mite repellent and B-grade miticide. This study has emphasized the significances of VORO in the food and textile industries as a potential additive. [ABSTRACT FROM AUTHOR]

For near‐net shape hot isostatic pressing (HIP) process, the interaction between capsules and consolidating powders at a high pressure and temperature leads to a strong interfacial element diffusion, which is harmful to the surface microstructure and mechanical properties of components. The effects of iron and carbon, in SS400 steel capsules, on the surface microstructure and mechanical properties of the FGH4096M superalloy during HIP are investigated. Results show that the interfacial difussion between the SS400 steel and FGH4096M is divided into three zones: ferrite‐martensite‐austenite mixture zone (≈32.3 µm), Fe‐rich Ni‐Fe‐based superalloy zone (≈27.5 µm), and Ni‐rich Ni‐Fe‐based superalloy zone (≈34.8 µm). The γ′ phase starts to be formed when the mass fraction of iron is below ≈27.2%. The γ′ morphology changes from fine sphere to cuboidal and butterfly‐like shapes as the mass fraction of iron is decreased successively. There is no obvious carbon diffusion around the interface due to a low carbon concentration in the capsule. The Vickers microhardness profile shows an increase, then a decrease, and eventually becomes stable at 425HV. Based on the above conclusions, an understanding of the Fe and C diffusion mechanism at the interface and its extension toward the FGH4096M side is achieved. [ABSTRACT FROM AUTHOR]

Antioxidant and antimicrobial chitosan (CS) films incorporated with different concentrations (0, 3, 6 and 9% w/w based on chitosan) of pomegranate peel powder (PPP) were prepared through a simple and low-cost process and characterized. The physicochemical property, antioxidant and antibacterial properties of the films were investigated. Results showed that incorporation with PPP increased the thickness, water solubility (WS), water vapor permeability (WVP), opacity and total phenolic content (TPC) of chitosan films, but decreased the moisture content (MC) and mechanical property. Fourier transform infrared (FTIR) spectroscopy indicated the formation of hydrogen bonds between chitosan and PPP. In addition, scanning electron microscopy (SEM) analysis presented that microstructural attributes of chitosan film changed by enriching with pomegranate peel. The films with concentrations of PPP at 6 and 9% presented great ultraviolet-visible light barrier properties. Moreover, the antioxidant ability of films with PPP was significantly increased compared to the chitosan film. The addition of PPP also promoted the antibacterial capacity of the control film. These results revealed that incorporation of PPP in chitosan film could fabricate an economical active film with antioxidant and antibacterial properties, and which had the potential for developing food-grade packaging material. • Chitosan films incorporated with pomegranate peel were prepared for the first time. • The processing of active film was low cost and simple. • The active film showed excellent ultraviolet-visible light barrier capacity. • The antioxidant and antibacterial properties of chitosan film were improved by adding pomegranate peel. [ABSTRACT FROM AUTHOR]

Developing high‐performance, low‐loading, Ir‐based electrocatalysts for the oxygen evolution reaction (OER) in acidic media is still a great challenge. Herein, we fabricated an iridium manganese catalyst with only 5 % iridium. The influence of the manganese dioxide phase states (α‐, β‐, γ‐ and δ‐MnO2) on the OER performance of IrO2/MnO2 catalysts was investigated. α‐MnO2, as the substrate, can generate smaller iridium particles and more high‐valence‐state iridium to promote OER performance. Therefore, the 5 % IrO2/α‐MnO2 electrocatalyst exhibits excellent electrocatalytic OER performance with a high mass activity of 216.67 A/gIr and 655.33 A/gIr at 1.53 V in acidic and alkaline media, respectively, significantly outperforming commercial IrO2. [ABSTRACT FROM AUTHOR]

Abstract We report a CeO 2 incorporated cobalt oxide electrode with abundant nano-sized interfaces. The as-prepared heterostructures exhibit remarkable oxygen evolution reaction (OER) activity and excellent stability, surpassing the pristine cobalt oxide and the state-of-art RuO 2. Further DFT calculations and experimental results indicate that the improved OER performance of CoO-CeO 2 heterostructures originates from the hierarchically porous structure, large surface area and high electron density around Co sites. The armouphous phase is formed during OER test due to surface Ce leaching, which can further promoted the performance of the hybrids. This work elucidates the cooperative effects and in situ transformation of CeO 2 -incorporated cobalt oxide in water oxidation, providing a valuable guideline for designing electrocatalysts. Highlights • The CoO-CeO 2 heterostructures are prepared via a self-assembling method. • The hybrids feature abundant interfaces and hierarchically porous structure. • The hybrids show excellent OER activity and long-term stability. • The enhancement is due to large surface area and strong electronic interaction. • The in situ formed amorphous phase can further improve OER performance. [ABSTRACT FROM AUTHOR]

Controllable modification of hydrophilic groups on tubular nanostructured carbon with hollow macroporous core/mesoporous shell (TNC-HMC/MS) was systematically studied and the mesoporous structure of TNC-HMC/MS has been kept. Different oxidants were used to modify the TNC-HMC/MS. Results revealed that the TNC-HMC/MS could be modified with carboxyl or hydroxy by different oxidants. More importantly, the BET/BJH results indicated that the mesoporous shell of TNC-HMC/MS has not been destroyed. In addition, water-soluble ammonium metatungstate has been encapsulated into the hollow core of TNC-HMC/MS and formed nanodot, bamboo-like and nanowire morphology. [ABSTRACT FROM AUTHOR]

The main research described in this paper includes three sections. First, research on the response of the stainless steel ball-shaped ionisation chamber by experimental methods. Secondly, calculation of the response of the chamber with the general Monte Carlo EGS4 code in order to compare with the equivalent electron source theory by calculation methods. Finally, calculation of the response of the ionisation chamber with the equivalent electron source theory. The results show that the calculated results of the equivalent electron source theory coincide very well with those of the experiments when the atomic number of the chamber wall is close to one of the gases (such as Ar and Kr), and the calculated results coincide with those of the experiments to a certain extent when the atomic number of the chamber wall is not close to one of the gases (such as He and Xe). [ABSTRACT FROM PUBLISHER]

The pH-responsive double hydrophilic block copolymer poly(ethylene glycol)-b-poly(methacylic acid-co-4-vinyl benzylamine hydrochloride salt) (PEG-b-PMAA/PVBAHS) was synthesized. A series of PEG-b-PMAA/PVBAHS with different molecule weights and compositions were characterized by IR, 1H-NMR, elemental analysis and TGA. With different MAA/VBAHS ratio, the PEG-b-PMAA/PVBAHS copolymers had the different isoelectric point (IEP). Supermolecular structures of the block copolymers could be formed by the interionic interactions at different solution pH. Experiment results showed that the structures of the pH-responsive copolymers in aqueous solution could be changed at different pH environments. The aggregation of this double hydrophilic block copolymer in aqueous solution was determined by both of solution pH and copolymer composition. [ABSTRACT FROM AUTHOR]

The copper-based catalyst is considered to be the only catalyst for electrochemical carbon dioxide reduction to produce a variety of hydrocarbons, but its low selectivity and low current density to C2 products restrict its development. Herein, a core-shell xZnO@yCu2O catalysts for electrochemical CO2 reduction was fabricated via a two-step route. The high selectivity of C2 products of 49.8% on ZnO@4Cu2O (ethylene 33.5%, ethanol 16.3%) with an excellent total current density of 140.1 mA cm−2 was achieved over this core-shell structure catalyst in a flow cell, in which the C2 selectivity was twice that of Cu2O. The high electrochemical activity for ECR to C2 products was attributed to the synergetic effects of the ZnO core and Cu2O shell, which not only enhanced the selectivity of the coordinating electron, improved the HER overpotential, and fastened the electron transfer, but also promoted the multielectron involved kinetics for ethylene and ethanol production. This work provides some new insights into the design of highly efficient Cu-based electrocatalysts for enhancing the selectivity of electrochemical CO2 reduction to produce high-value C2 products. [ABSTRACT FROM AUTHOR]

Fresh eggs are important to food processing and people consumption. In this study, Raman technique combined with chemometrics method were carried out to monitor egg freshness by scanning external information of egg shell. The Raman spectra were collected from the top, waist, and bottom of 125 eggs' shell surface monitored for 60 days, respectively. Then the partial least squares regression model of 100–3000 cm−1 was established with the physical and chemical indices of freshness. During the process of modeling, various pre-processing methods were performed on the Raman spectrum, and it was found that the first derivative or the second derivative would produce the best effect. In addition, by comparing the modeling effects of the Raman spectrum at different detection sites, it was found that the model at the egg top was the best. The correlation coefficients with Haugh unit, albumen pH and air chamber diameter were all above 0.9, and air chamber height was above 0.8, which indicated that there was a strong correlation between the Raman spectrum of the egg shell surface and the freshness. This study provided a new, rapid and simple method for the non-destructive and on-site testing of egg freshness. • The chemical information outside eggshell was used to characterize freshness. • Raman combined with chemometrics method could predict egg freshness. • The non-destructive testing of egg freshness might be achieved at the egg top. [ABSTRACT FROM AUTHOR]

• Cinnamomum camphora chvar. Borneol essential oil (BEO) was obtained. • Neutral cellulase assisted steam distillation (NCSD) enhanced yield of BEO. • Working parameters of NCSD were optimized through response surface methodology. • 62 volatile compounds in total were identified in BEO. • Majority of chemical constituents in BEO using NCSD remain unchanged. Cinnamomum camphora chvar. Borneol essential oil (BEO) has potential biological activity and has attracted considerable interest. In this study, neutral cellulase assisted-steam distillation (NCSD) was first developed to extract BEO, followed by optimizing NCSD through single-factor test (SFT) and response surface methodology (RSM). The processing conditions of NCSD were optimized as follows: addition of neutral cellulase (0.36 FPU/g of fresh leaves), duration of enzymolysis (5.39 h), temperature (51.47 °C), and pH (6.15). The predicted yield of BEO using NCSD was 1.03% within 95% confidence intervals of the actual yield of BEO (1.03 ± 0.03%), which was 58% higher than the yield of BEO using conventional steam distillation (SD) without neutral cellulase pre-treatment (0.65 ± 0.04%). Moreover, chemical constituents of BEO using NCSD and SD were evaluated and compared. Results show that 62 volatile compounds were identified, and majority of functional compounds in the BEO using NCSD and SD were detected simultaneously, e.g. borneol, β-pinene, and β-cadinene. A significantly higher proportion of compounds with relatively lower molecular weight (MW) ranging from 130 to 150 and higher MW ranging from 205 to 225 were detected in the BEO using NCSD, which may contribute to a stronger flavoring impact and influence the overall flavor profile of the BEO. Therefore, significance of this study is to develop the NCSD as a more effective method than the SD for extracting the BEO from Cinnamomum camphora chvar. Borneol fresh leaves without compromising its quality and remaining the majority of chemical consitutents unchanged. [ABSTRACT FROM AUTHOR]

Finding cost-effective, active and durable catalyst materials for energy applications, such as electrocatalytic hydrogen production, is an intriguing challenge. Here, a facile and effective approach to the design and construction of two-dimensional MoS 2 and WS 2 interleaved nanowalls with maximum exposures of active edges on silk-derived N-doped carbon fibers (SNCF) was demonstrated. The morphological evolutions of the MoS 2 and WS 2 nanocrystals on the SNCF from crescent-like nanosheets to an interleaved nanowall network can be obtained by adjusting the concentrations of the Mo and W precursors. These robust MoS 2 /SNCF and WS 2 /SNCF electrocatalysts exhibit prominent hydrogen evolution reaction (HER) activities with onset potentials of −40 and −96 mV and Tafel slopes of 60 and 66 mV dec −1 , respectively. The overpotentials ( η ) at j = −10 mA cm −2 for MoS 2 /SNCF and WS 2 /SNCF are −102 and −157 mV, respectively. In addition, MoS 2 /SNCF and WS 2 /SNCF are both able to sustain continuous HER operation for 10 h under working conditions with only a slight degradation in current densities, implying excellent durability and a prospect for practical applications. [ABSTRACT FROM AUTHOR]