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The effect of the microstructure of siliconized graphite on tribological properties is investigated by using a high-temperature and high-pressure water-lubricated tribometer on a self-mated ring-on-ring configuration under an applied load of 500–1500 N with a spindle speed of 100–5000 rpm in both 90 °C (5 MPa) and 25 °C (1 MPa) water environments, respectively. The Stribeck curves measurement and continuous wear tests are performed and analyzed in both water environments. The wear behaviors of the graphite, SiC, and free-silicon phases in siliconized graphite are demonstrated to explore the wear mechanism. The larger wear depths of a low-worn surface roughness on the three phases contribute to the boundary lubrication. The shallower wear depths are observed on the SiC and Si phases under the mixed lubrication, corresponding to partial contact wear of surface asperities. The wavy surface of the SiC phase and uniform flow-oriented striae of the Si phase are attributed to hydrodynamic lubrication, caused by full water film scouring the worn surface. Finally, an integrated evaluation method of G duty parameters is successfully used to identify the lubrication regimes of siliconized graphite from the boundary, mixed, to hydrodynamic lubrications for a water-lubricated thrust bearing application in the main coolant pump of a nuclear power plant. [ABSTRACT FROM AUTHOR]

Simple Summary: Heat stress (HS) constantly happens to dry lot feeding sheep during the summer, inevitably causing substantial losses to animal production due to its unfavorable effects on health, welfare and production performance. In the current study, HS played disadvantageous roles in growth performance, physiological indices, antioxidative capacity, immunomodulation, ruminal fermentation and microbial composition. Dietary supplementation with folic acid and taurine can effectively ameliorate adverse effects of HS by improving the proportion of beneficial bacteria such as Quinella and Succinivibrio and decreasing the abundance of harmful bacteria such as Asteroleplasma. This study provides a practical approach for the application of folic acid and taurine in HS-challenged sheep. The aim of this study was to investigate if the supplementation of folic acid and taurine can relieve the adverse effects of different levels of heat stress (HS) on growth performance, physiological indices, antioxidative capacity, immunity, rumen fermentation and microbiota. A total of 24 Dorper × Hu crossbred lambs (27.51 ± 0.96 kg) were divided into four groups: control group (C, 25 °C), moderate HS group (MHS, 35 °C), severe HS group (SHS, 40 °C), and the treatment group, under severe HS (RHS, 40 °C, 4 and 40 mg/kg BW/d coated folic acid and taurine, respectively). Results showed that, compared with Group C, HS significantly decreased the ADG of lambs (p < 0.05), and the ADG in the RHS group was markedly higher than in the MHS and SHS group (p < 0.05). HS had significant detrimental effects on physiological indices, antioxidative indices and immune status on the 4th day (p < 0.05). The physiological indices, such as RR and ST, increased significantly (p < 0.05) with the HS level and were significantly decreased in the RHS group, compared to the SHS group (p < 0.05). HS induced the significant increase of MDA, TNF-α, and IL-β, and the decrease of T-AOC, SOD, GPx, IL-10, IL-13, IgA, IgG, and IgM (p < 0.05). However, there was a significant improvement in these indices after the supplementation of folic acid and taurine under HS. Moreover, there were a significant increase in Quinella and Succinivibrio, and an evident decrease of the genera Rikenellaceae_RC9_gut_group and Asteroleplasma under HS (p < 0.05). The LEfSe analysis showed that the genera Butyrivibrio, Eubacterium_ventriosum_group, and f_Bifidobacteriaceae were enriched in the MHS, SHS and RHS groups, respectively. Correlated analysis indicated that the genus Rikenellaceae_RC9_gut_group was positively associated with MDA, while it was negatively involved in IL-10, IgA, IgM, and SOD (p < 0.05); The genus Anaeroplasma was positively associated with the propionate and valerate, while the genus Succinivibrio was negatively involved in TNF-α (p < 0.05). In conclusion, folic acid and taurine may alleviate the adverse effects of HS on antioxidant capacity, immunomodulation, and rumen fermentation of lambs by inducing changes in the microbiome that improve animal growth performance. [ABSTRACT FROM AUTHOR]

The superhydrophobic surfaces with three kinds of nanopillars on polypropylene (PP) substrates are fabricated by a plasma nanotexturing technique comprising oxygen‐plasma treatment (OPT) followed by fluorocarbon polymer deposition (FPD). The diameters of nanopillars and spacing distances between nanopillars are tuned under the different OPT and FPD duration times. The wettability and contact electrification on the surfaces are analyzed under the water droplet impact by changing the impacting droplet number, Weber number, and salt concentration. The dense or wide nanopillars favor high contact charge on the surfaces with nanopillars, arousing the damage of the superhydrophobicity with low adhesion. The low contact charge impacting the droplets with high salt concentration has a weakened effect on the superhydrophobicity of the surfaces with nanopillars. [ABSTRACT FROM AUTHOR]

The carbon fiber‐reinforced polyetheretherketone (CF/PEEK) composite coatings with two types of short CFs, that is, 300‐ and 600‐mesh, each in the contents of 10 and 30 wt% are deposited in comparison with the pure PEEK coatings by using a flame spraying method, respectively. The 300‐mesh CFs with intact morphology and the 600‐mesh CFs preserving fractured shape and higher graphitization degree are selected as the reinforced fillers in the CF/PEEK composite coatings. The flame‐sprayed CF/PEEK composite coatings show the increased porosity with the higher CF contents. The adding of CFs in the flame‐sprayed CF/PEEK composite coatings limits the thermal degradation of PEEK and restrains the PEEK crystallization showing low crystallinity degree and small crystallite size. The composite coatings in 10 wt% CF content exhibit the optimized nanoindentation behavior and tribological property. The 300‐mesh CFs with large length and intact morphology in flame‐sprayed CF/PEEK composite coatings lead to the increased surface hardness by 1.31 times over that of the pure PEEK coatings. The 600‐mesh CFs with higher graphitization degree contribute to better tribological property of flame‐sprayed CF/PEEK composite coatings with an order of magnitude lower specific wear rate. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus that causes acute diarrhea, vomiting, dehydration, and a high mortality rate in neonatal piglets. In recent years, PEDV has been associated with co-infections with other swine enteric viruses, including porcine rotavirus (PoRV), resulting in increased mortality among newborn piglets. In this paper, we developed a bivalent vaccine against PEDV and PoRV by constructing a recombinant PEDV encoding PoRV VP7 (rPEDV-PoRV-VP7). The recombinant virus was constructed by replacing the entire open reading frame 3 (ORF3) in the genome of an attenuated PEDV strain YN150 with the PoRV VP7 gene using reverse genetic systems. Similar plaque morphology and replication kinetics were observed in Vero cells with the recombinant PEDV compared to the wild-type PEDV. It is noteworthy that the VP7 protein could be expressed stably in rPEDV-PoRV-VP7-infected cells. To evaluate the immunogenicity and safety of rPEDV-PoRV-VP7, 10-day-old piglets were vaccinated with the recombinant virus. After inoculation, no piglet displayed clinical symptoms such as vomiting, diarrhea, or anorexia. The PoRV VP7- and PEDV spike-specific IgG in serum and IgA in saliva were detected in piglets after rPEDV-PoRV-VP7 vaccination. Moreover, both PoRV and PEDV neutralizing antibodies were produced simultaneously in the inoculated piglets. Collectively, we engineered a recombinant PEDV expressing PoRV VP7 that could be used as an effective bivalent vaccine against PEDV and PoRV. [ABSTRACT FROM AUTHOR]

Inspired by the antireflection and antiwetting functionalities of dragonfly wings decorated with random nanopillars and a wax layer, a facile technique to endow the same functionalities has been devised. In this two‐step plasma nanotexturing technique, first oxygen plasma treatment is implemented to grow the random nanopillars on the polymethyl methacrylate (PMMA) surfaces, and then C4F8 plasma polymer deposition is carried out so that the thin fluorocarbon film with a low surface free energy and refraction index covers the random nanopillars. The biomimetic PMMA surfaces exhibit excellent broadband and omnidirectional antireflection properties and robust antiwetting properties under the water droplet impact. The superhydrophobicity at the slippery Cassie state was maintained under the natural oscillation of residual droplets. [ABSTRACT FROM AUTHOR]

Novel hierarchical SiC–SiO2 heterostructures were synthesized on a graphite paper substrate via a catalyst free method. The morphology, microstructure and composition were characterized by SEM, HR-TEM, EDS and XRD. Results revealed that the hierarchy of SiC–SiO2 heterostructures consisted of nanochain structures and nanoweb structures located in different layers of the graphite paper substrate. The nanochain structures were SiC–SiO2 nanochains coated by an exterior SiO2 shell, in which the SiO2 beads were chained to the SiC nanostructure. The nanoweb structures showed that many intersecting SiC nanostructures were encapsulated in irregular SiO2 agglomerates. The formation of hierarchical SiC–SiO2 heterostructures was dependent on the synthesis temperature. The VS process followed by a modulation process was proposed to elucidate the formation mechanism of such hierarchical SiC–SiO2 heterostructures. [ABSTRACT FROM AUTHOR]

Novel and intelligent plasma copolymers based on hydrophilic/hydrophobic monomers with tunable wettability and pH-responsiveness are demonstrated. A series of plasma copolymer coatings with various carboxylic acid and fluorocarbon group ratio are prepared on the low-density polyethylene (LDPE) surfaces via capacitively coupled radio frequency plasma (CCP). The static water contact angles (SWCA) of C4F8-co-AA plasma polymer coatings on nanotextured LDPE surfaces tuned from 163 to 4°. These C4F8-co-AA plasma polymer coatings showed different pH-responsiveness by the combined effect of the carboxylic acid to fluorocarbon group ratios and surface nanotexture. The increase of carboxylic acid groups of C4F8-co-AA plasma polymers shifted the reversibly switchable wettability of pH-responsiveness towards low SWCA range. The magnifying effect of surface nanotexture on pH-responsiveness was also observed. [ABSTRACT FROM AUTHOR]

The SiC nanofibres with a length of few millimetres were synthesized successfully on carbon fabrics using a catalyst-free method. The Si and SiO2 powder mixtures functioned as a source for the generation of gaseous species. Following the chemical vapour reaction route, abundant SiC nanofibres with near stoichiometric composition and high crystallinity were grown on the surfaces of carbon fibres. The phase, morphology and crystal structure were characterized to reveal the nucleation and growth mechanism. SiC nanofibres presented a pagoda structure, which is a consecutive stacking of hexagonal segments with a high density of stacking faults. Combining the fabrication process with an analysis of the morphology and crystal structure, both the vapour–solid mechanism and the screw dislocation-driven mechanism are responsible for the nucleation and the growth of SiC nanofibres in the current study. The significant advantage of the present process is that it can be conveniently implemented and provides an approach to allow the fabrication of SiC nanostructures on a variety of carbonaceous substrates without the assistance of a catalyst, leading to less expensive, long length and high purity production of nanostructures. [ABSTRACT FROM AUTHOR]

The process of crack initiation and propagation during fatigue loading in aluminium specimens was quantitatively monitored with the electromechanical impedance (EMI) method. The displacement-controlled fatigue testing mode was used and the stages of crack initiation and propagation consisted of up to 90% and 80% of the total life of the two types of specimen, without and with crack starter notch, respectively. The impedance signatures of the piezoelectric ceramic (PZT) sensors were measured online with the specimens fixed to the fatigue testing machine, and the signatures measured after 200 cycles were selected as the baselines when the area and depth of the indentation were stabilised. The resonant frequency shift Δf and root mean square deviation (RMSD) of the impedance signatures were extracted as damage indicators and compared with the crack length measured from the photographs of the fatigue fracture zone. The results show that at the crack initiation stage, before the generation of a 0.22 mm fatigue crack, the values of Δf and RMSD increased obviously to 0.6 kHz and 11.68%, respectively. The initial pre-crack damages can be effectively monitored with these two indicators. At the crack propagation stage, with the increase of crack length from 0.58 to 9.40 mm, the values of Δf and RMSD both increased monotonically. The increment trend of Δf was evidently similar to that of crack length and the RMSD value was more sensitive to the initial expansion of crack length in the first 5000 cycles. This study confirms that the EMI method can be potentially employed for the monitoring of in-service fatigue damage of engineered products and structures. [ABSTRACT FROM AUTHOR]

Abstract: Based on the ion current density model of TEMP type ion beam accelerator, and utilizing the deposited energy of the high-intensity pulsed ion beam (HIPIB) in tungsten by Monte Carlo method as source term, a two-dimensional thermal conduction model controlling the irradiation process was built. The evolution of tungsten temperature during the irradiation period was obtained and analyzed. The results show that the melted thickness of tungsten surface is about 0.3μm at shooting center of target irradiated by HIPIB at the end of a pulse under the ion peak current density of 100 A/cm2, the materials of tungsten surface in thickness of about 0.2μm reach boiling point; and among the ion peak current density of 50-200 A/cm2, the melting ablation depth is less than 1μm according to the calculation. While the ion peak current density increased to about 330 A/cm2, the vaporizing ablation phenomenon appeared on the shooting center of tungsten surface. [Copyright &y& Elsevier]

We prepared gradated nano-transient layers at different interfaces between deposited film and substrates by high-intensity pulsed ion beam (HIPIB) irradiation. The deposited film was (Al-Si) alloy and substrates were Ni and Ti, respectively. The gradated nano-transient layers at different interfaces were measured by Rutherford backscattering, its spectra were solved by SIMNRA code and then the microstructures of the gradated nano-transient layers at the interfaces of these two irradiated samples were obtained. The experimental results were analyzed by STEIPIB code. The formation of the gradated distribution of element contents in nano-transient layer at the interface can eliminate the abrupt changes of thermal and elastic characteristics at the interface. And, it can greatly reduce the mismatch of thermal expansion coefficients and Young's modulus at the interface between deposited film and substrate. Thus, after the formation of the gradated nano-transient layer, the adhesion at the interface between different materials can be enhanced and the level of thermal stresses can also be reduced in the case of thermal loading. [ABSTRACT FROM AUTHOR]

Front Cover: Monomer feed rate regulates the chemical structure of smart plasma copolymer coating and its surface wettability in various pH environment. The combined effect of surface chemical compositions and surface roughness causes tunable wettability from superhydrophobicity to superhydrophilicity of smart plasma copolymer coatings. Further on, the presence of the carboxylic acid functional group in plasma copolymer coatings made this surface wettability switchable for different pH environment. Further details can be found in the article by I. Muzammil et al. on 1700053. [ABSTRACT FROM AUTHOR]

Large quantities of multi-shaped SiC nanofibers were successfully synthesized on carbon fibers at elevated temperatures via a catalyst-free chemical vapor reaction method. FE-SEM and TEM investigations revealed that all SiC nanofibers grew along the [111] crystal orientation. The diameters of SiC nanofibers were in the range of 100–400 nm. The length of nanofibers was about several hundreds of micrometers. The vapor-solid mechanism was applied to understand the growth of the multi-shaped SiC nanofibers. The change in morphological shape of SiC nanofibers could be attributed to the temperature-dependent growth kinetics, which strongly associated with the partial pressure of SiO. [ABSTRACT FROM AUTHOR]

High purity SiC nanostructures were grown in situ on the surfaces of C/SiC composites by the chemical vapor reaction route to improve the anti-oxidation capability of C/SiC composites. It was found that the SiC nanostructures formed a dense cluster with a thickness of about 20 μm. The nanostructures mainly included nanoparticles and nanorods. The oxidation tests found that the SiC nanostructures could significantly improve the anti-oxidation capability of C/SiC composites, particularly, at the temperature beyond 900 °C. The improvement of the anti-oxidation capability of the C/SiC composites was attributed to the formation of a silica layer. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate if the supplementation of folic acid and taurine can relieve the adverse effects of different levels of heat stress (HS) on growth performance, physiological indices, antioxidative capacity, immunity, rumen fermentation and microbiota. A total of 24 Dorper × Hu crossbred lambs (27.51 ± 0.96 kg) were divided into four groups: control group (C, 25 °C), moderate HS group (MHS, 35 °C), severe HS group (SHS, 40 °C), and the treatment group, under severe HS (RHS, 40 °C, 4 and 40 mg/kg BW/d coated folic acid and taurine, respectively). Results showed that, compared with Group C, HS significantly decreased the ADG of lambs ( p < 0.05), and the ADG in the RHS group was markedly higher than in the MHS and SHS group ( p < 0.05). HS had significant detrimental effects on physiological indices, antioxidative indices and immune status on the 4th day ( p < 0.05). The physiological indices, such as RR and ST, increased significantly ( p < 0.05) with the HS level and were significantly decreased in the RHS group, compared to the SHS group ( p < 0.05). HS induced the significant increase of MDA, TNF-α, and IL-β, and the decrease of T-AOC, SOD, GPx, IL-10, IL-13, IgA, IgG, and IgM ( p < 0.05). However, there was a significant improvement in these indices after the supplementation of folic acid and taurine under HS. Moreover, there were a significant increase in Quinella and Succinivibrio , and an evident decrease of the genera Rikenellaceae&#95;RC9&#95;gut&#95;group and Asteroleplasma under HS ( p < 0.05). The LEfSe analysis showed that the genera Butyrivibrio , Eubacterium&#95;ventriosum&#95;group , and f&#95;Bifidobacteriaceae were enriched in the MHS, SHS and RHS groups, respectively. Correlated analysis indicated that the genus Rikenellaceae&#95;RC9&#95;gut&#95;group was positively associated with MDA, while it was negatively involved in IL-10, IgA, IgM, and SOD ( p < 0.05); The genus Anaeroplasma was positively associated with the propionate and valerate, while the genus Succinivibrio was negatively involved in TNF-α ( p < 0.05). In conclusion, folic acid and taurine may alleviate the adverse effects of HS on antioxidant capacity, immunomodulation, and rumen fermentation of lambs by inducing changes in the microbiome that improve animal growth performance.

Recently, the relationship between the goat host and its gastrointestinal microbiome has emerged as a hallmark of host-microbiota symbiosis, which was indispensable for the proper physiological function that convert the plant biomass to livestock products. However, little integrative information about the establishment of gastrointestinal microflora in goats exists. Herein, we characterized the colonizing process of the bacterial community in the digesta and mucosa of the rumen, cecum, and colon of the cashmere goat from birth to adulthood to compare its spatiotemporal difference via 16S rRNA gene sequencing. A total of 1,003 genera belonging to 43 phyla were identified. Principal coordinate analysis unveiled the similarity of microbial community between or within each age group increased and gradually developed toward mature whatever in digesta or mucosa. In the rumen, the composition of the bacterial community in digesta differed significantly from in mucosa across age groups; whereas in the hindgut, there was a high similarity of bacterial composition between the in digesta and mucosa in each age group before weaning, while the bacterial community structure differed markedly between these two types of samples after weaning. Taxonomic analysis indicated that 25 and 21 core genera coexisted in digesta and mucosa of the rumen and hindgut, respectively; but their abundances differed considerably by GIT region and/or age. In digesta, as goats aged, a lower abundance of Bacillus was observed with higher abundances of Prevotella 1 and Rikenellaceae RC9 in the rumen; while in the hindgut, the genera Escherichia-Shigella , Variovorax , and Stenotrophomonas decreased and Ruminococcaceae UCG-005 , Ruminococcaceae UCG-010 , and Alistipes increased with age increased. In mucosa, the rumen showed microbial dynamics with increases of Butyrivibrio 2 and Prevotellaceae UCG-001 and decreases of unclassified&#95; f&#95;Pasteurellaceae ; while the genera Treponema 2 and Ruminococcaceae UCG-010 increased and Escherichia-Shigella decreased in the hindgut as goats aged. These results shed light on the colonization process of microbiota in the rumen and hindgut, which mainly include the initial, transit, and mature phases. Furthermore, there is a significant difference in the microbial composition between in digesta and mucosa, and both these exhibit a considerable spatiotemporal specificity., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Yin, Lei, Wang, Yang, Zhang and Chen.)

SnS 2 with high theoretical capacity has been impeded from practical applications as the anode of lithium-ion (Li-ion) batteries due to its large volume expansion and fast capacity decay. A nanostructure of the SnS 2 semifilled carbon nanotube (SnS 2 @CNT) has been realized by plasma-assisted fabrication of Sn semifilled CNT (Sn@CNT) followed by post-sulfurization. When serving as the anode of a Li-ion battery, SnS 2 @CNT delivers an initial discharge capacity of 1258 mAh g -1 at 0.3 A g -1 . Instead of capacity fading, SnS 2 @CNT shows inverse capacity growth to 2733 mAh g -1 after 470 cycles. The high-resolution transmission electron microscopy images show that the void in CNTs, after cycling, is fully filled with pulverized SnS 2 grains which have a shortened Li-ion diffusion path and enhanced surface area for interfacial redox reactions. In addition, the CNTs, like a pocket, confine the pulverized SnS 2 , maintain the electric contact and structural integrity, and thus allow the electrodes to work safely under long cyclic loadings and extreme temperature conditions.

The boundary-value problem for a Dyakonov-Tamm wave guided by a twist defect in a structurally chiral material and propagating along the bisector of the twist defect was formulated. The resulting dispersion equation was numerically solved. Detailed analysis showed that either two or three different Dyakonov-Tamm waves can propagate, depending on the value of the twist angle. These waves have different phase speeds and degrees of localization to the twist-defect interface.

The green up-conversion emissions centered at the wavelengths of about 534nmand 549nm of the Er 3+ doped silicate glass were recorded, using a 978 nm semiconductorlaser diode (LD) as an excitation source. The fluorescence intensity ratio (FIR) of the greenup-conversion emissions at about 534nm and 549nm in the Er 3+ doped silicate glass wasstudied as a function of temperature over the temperature range of 296K-673K. Themaximum sensitivity and the temperature resolution derived from the FIR of the green up-conversion emissions are approximately 0.0023K -1 and 0.8K, respectively. It isdemonstrated that the prototype optical temperature sensor based on the FIR technique fromthe green up-conversion emissions in the Er 3+ doped silicate glass could play a major role intemperature measurement.