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In this work, we studied a technology of laser-induced coloration of TC4 by surface oxidation, the aim is to explore the effect of thermal field on the marking color which is applied to control the color in single operating variable. The controllable coloration of TC4 surface at laser heating in the air was conducted; the surface morphology and microstructure of the specimens were examined by optical microscopy (OM) and scanning electron microscopy (SEM), the reflectance spectra of the oxide film were measured by optics spectrometer, and the color images are fabricated finally. [ABSTRACT FROM AUTHOR]

[Display omitted] • The heterostructured CoS 2 /Co is created by electrochemically-sulfonated reaction. • The as-prepared sulfur electrocatalyst exhibits enhanced Li-S kinetics. • The obtained cathode exhibits satisfactory performance under high sulfur loading. Lithium-sulfur (Li-S) batteries are showing a huge potentiality in the energy storage market owing to its high theoretical energy density and cost-effectiveness. However, there are still some thorny issues needed to be tackled before realizing their practical applications, including underperformed rate capability and unsatisfactory cycling stability. Herein, we have constructed the checkerboard-like heterostructured CoS 2 /Co nanoparticle inside porous carbon by the electrochemically-sulfonated reaction of lithium polysulfides (LiPS) and used them as sulfur electrocatalyst. Benefiting from this structure advantage, the catalyst can not only promote the chemical adsorption of LiPS, but also acts as promoter to provide coupled electrons to accelerate its redox reaction. Through synergistic enhancement, the checkerboard-like CoS 2 /Co heterostructure provides a boosted chemical adsorption and accelerated catalytic conversion of LiPS, rendering suppressed shuttle effect and enhanced Li-S kinetics. In addition, the porous carbon carriers offer abundant nanoscale pores to effectively immobilize sulfur and accommodate its volume expansion. Therefore, the CoS 2 /Co sulfur composites exhibit decent rate capability up to 5C and long-term cycling performance over 500 cycles at 1C with a capacity fading rate below 0.059% per cycle. Moreover, an admirable cyclic stability can also be achieved under raised sulfur loading of 7.13 mg∙cm−2 and low E/S ratio of 4.5 mL∙g−1. [ABSTRACT FROM AUTHOR]

The effects of laser energy density on the coloring effect were examined using a nanosecond fiber laser to color the surface of a TC4 Ti alloy. The surface of samples turns yellow, orange, purple, and blue as the single pulse energy density increases. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive spectroscopy (EDS) results demonstrated that a mixed film containing TiN and TiO was formed on the surface of samples after laser coloring. The TiN content in the mixed film reduced with increase in single pulse energy density, whereas the TiO content increased. Based on the equivalent medium and optics theory, the SCOUT optical simulation software was used to create a three-layer structure model of ambient/mixed film/Ti alloy substrate. The superposition of reflection and interference in the mixed film was simulated to examine the effect of the mixed film's composition and thickness on the reflective spectrum of sample. The reflective spectrum of different colors obtained by simulations and tests was extremely consistent, and the simulation composition and thickness of the mixed film were consistent with the tested results, indicating that the laser coloring mechanism is influenced by light interference between mixed films of different composition and thickness formed on the sample surface. [ABSTRACT FROM AUTHOR]

Abstract: A novel MoSi2–Al2O3 solar selective absorbing coating deposited on stainless steel (SS) substrate by magnetron sputtering is reported. The effects of the HMVF and LMVF absorption layers thickness and metal volume fraction on optical properties of the coatings are investigated. As the thickness or metal volume fraction of the HMVF or LMVF layers increases, it is found that the absorptance first increases and then decreases, this can be explained by the regularly changes of the reflectance spectrum. The position of the cutoff limit has a redshift as the thickness of the HMVF or LMVF layers or the metal volume fraction of the HMVF layer increases, which will induce the quick increase of the emittance with temperature. The cutoff limit is almost unchanged as the metal volume fraction of the LMVF layer increases. Most of the experimental results are consistent with the simulated results in the trends. [Copyright &y& Elsevier]

Highlights: [•] We first proposed to use a AlNi alloy to fabricated cermet absorption coating. [•] We obtained an excellent optical property AlNi–Al2O3 absorbing coating. [•] Preliminary thermal stability tests show AlNi–Al2O3 coating is promising for CSP. [ABSTRACT FROM AUTHOR]

Abstract: A new solar selective absorbing coating of NbTiON/SiON was prepared on Cu substrate using a reactive magnetron sputtering method. The new coating exhibits a high absorptance (α) of 0.95 and a low emittance (ε) of 0.07, and the thickness of NbTiON and SiON layers was optimized to achieve high solar selectivity. The spectral properties (α/ε) of the coating on Cu substrate are stable (0.94/0.08) even after heat-treatment at 500°C in vacuum for 40h, but decreased at 600°C. If the substrate is replaced by stainless steel (SS), the coating exhibits better stability, which indicates its potential applications in intermediate temperate solar absorber. [Copyright &y& Elsevier]

To evaluate the safety and efficacy of an enhanced recovery after surgery (ERAS) program for intraspinal tumors in a single-institutional prospective randomized controlled trial. A multimodal and multidisciplinary ERAS protocol for intraspinal tumor surgery was developed. A total of 94 enrolled patients were randomized into 2 groups: 48 were managed following the ERAS protocol (ERAS group), and 46 received conventional perioperative care (control group). The primary end point was postoperative length of stay (LOS). The secondary outcomes included postoperative pain score and pain medication use, urinary catheterization, ambulation, mortality, reoperation/readmission rates, complication rates, patient satisfaction, and overall cost. A significant reduction in LOS was achieved in patients undergoing ERAS protocol compared with the controls (5 vs. 8 days; P < 0.0001). Moreover, patients in the ERAS group had better postoperative pain scores (1.0 ± 1.3 vs. 1.9 ± 1.3; P = 0.007), decreased use of patient-controlled analgesia (4.2% vs. 19.6%; P = 0.020) and oral opioid (37.5% vs. 58.7%; P = 0.040), early urinary catheter removal (58.3% vs. 6.5%; P < 0.0001), greater ambulation (68.8% vs. 17.4%; P < 0.0001), and higher satisfaction scores (91.8 ± 4.4 vs. 88.2 ± 6.8; P = 0.022) than did the control group. There were no deaths or 30-day readmission/reoperation in both groups, nor did the postoperative complication rates differ between groups. The ERAS protocol for intraspinal tumor surgery seems to be feasible, effective, and safe in shortening postoperative LOS, improving postoperative pain control with reduced opioid use, and accelerating functional recovery without increasing rates of complications or reoperation/readmission. Adoption of spine ERAS programs could be encouraged in practice, although validation with larger-scale multicenter trials is warranted. [ABSTRACT FROM AUTHOR]

Semiconducting ternary metal oxide thin films exhibit a promising application for solar energy conversion. However, the efficiency of the conversion is still limited by a band gap of a semiconductor, which determines an obtainable internal photovoltage for solar water splitting. In this report the tunability of the tin tungstate band gap by O 2 partial pressure control in the magnetron co-sputtering process is shown. A deficiency in the Sn concentration increases the optical band gap of tin tungstate thin films. The optimum band gap of 1.7 eV for tin tungstate films is achieved for a Sn to W ratio at unity, which establishes the highest photoelectrochemical activity. In particular, a maximum photocurrent density of 0.375 mA cm−2 at 1.23 V RHE and the lowest reported onset potential of −0.24 V RHE for SnWO 4 thin films without any co-catalyst are achieved. Finally, we demonstrate that a Ni protection layer on the SnWO 4 thin film enhances the photoelectrochemical stability, which is of paramount importance for application. Image 1 • Variation of oxygen partial pressure changes Sn to W ratio which tunes the band gap. • Optimum band gap (1.7 eV) results in the highest photocurrent density (0.375 mA cm−2). • The lowest onset potential of - 0.24 V RHE is achieved for tin tungstate film. • Photoelectrochemical stability of the films is improved by NiO x protection layer. • Initial open circuit potential of 0.107 V is measured upon AM 1.5 illumination. [ABSTRACT FROM AUTHOR]

• A novel laser-plasma arc hybrid welding system is developed, which solves the dilemma that coaxial recombination is challenging to achieve before. • The composite plasma in coaxial laser-plasma hybrid welding can make the heat redistribution. • The plasma morphology of hybrid welding turns to be drum-shaped from bell shape, indicating heat redistribution between heat sources. • The electron temperature Te and ion density Ni of the plasma arc is calculated and analyzed by Langmuir double probe. A novel coaxial laser-plasma hybrid welding method defined as "laser-soft plasma coaxial hybrid welding" was developed and studied. The plasma characteristics evolution, including plasma morphology, static electrical characteristic, and physical information of this welding method, was studied with the based material of TC4 alloy. Laser welding and plasma welding were carried out and used as comparative experiments. The plasma morphology of hybrid welding combines the characteristics of laser-induced plasma and arc plasma. The static electrical characteristic indicates that laser and plasma interact and influence each other but with different mechanisms under different current conditions. Physical information such as plasma electron temperature and ion density show that composite plasma can rapidly increase the heat source energy and ionization rate. To sum up, the coaxial plasma arc can increase the laser effect and redistribute the heat of the compound heat source, leading to a widened bead weld and better welding gap adaptability. This work provides an effective method and reference for hybrid welding process design and control in the practical industry. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract This investigation was focused on the laser cladding of FeCrNi coating. In our study, the characteristics of the FeCrNi coating have been studied, the morphology and microstructure of the cladding layers were analyzed by optical microscopy (OM) and scanning electron microscopy (SEM), the chemical composition was measured by energy dispersive spectrometer (EDS), the hardness were measured by microhardness tester. The thermal field in the laser cladding of FeCrNi coating has been calculated, the cooling rate of moving solid-liquid interface has been studied. At last, the hardness distribution of each cladding layer has been measured. [ABSTRACT FROM AUTHOR]

Tellurite based glasses have been prepared with various glass compositions such as yBi 2 O 3 -xZnO-(100 − x − y)TeO 2 glass system (y = 0.2, 1.0, 2.0, 3.0, 4.0, 5.0, and 8.0 mol% ratio and x = 14, 19, 19.8, and 20 mol%). The purpose of the work is to investigate the effect of glass compositions on the structure and hardness under the indentation loading test. Up till now, the experiences of the preparation of tellurite based glasses showed that it has high fragility structure at room temperature compared to boroxide, and chalcogenide-based glass materials. In this study, the thermal, mechanical and structural properties of Bi - based tellurite optical glass materials were investigated at room temperature. Results indicated that increased refractive index ratio of Bi has pronounce effect upon the transition temperature while the hardness value of the lassy material showed a reduction in response to this increased refractive index value of Bi. The obtained results further could be correlated with compositions that effects on the structural changes [for TeO 4 (tbp) to TeO 3 (tb)] having non-binding oxygen (NBO) due to the elastic deformation of Te O bonding and expansion of interatomic distances when considered the data of the Vickers' hardness, FT-IR, and Raman spectra. Here, it can also be emphasized that obtained the thermal stability, (T = T x − T g ), of the glass material, decreases from 80 to 37 °C as the melting temperature increases from 800 to 1025 °C, possibly leading to a decrease in microhardness and deformation in the glass materials. [ABSTRACT FROM AUTHOR]

In this work, the NbTiSiN and NbTiSiON layers are used instead of NbTiN and NbTiON layers to further improve the thermal stability of Al/NbTiN/NbTiON/SiO 2 multilayer solar selective absorbing coating. The thermal stability of Si-doped individual layers and multilayer coatings are investigated. The X-ray diffraction (XRD) results show that Si incorporation into NbTiN (NbTiSiN) layer does not change its preferred orientation, and the Si-doped NbTiON (NbTiSiON) layer remains in amorphous phase. On the other hand, by introducing Si into NbTiN and NbTiON layers induce significant improvement of the oxidation resistance at 500 °C in air. After ageing in air at 500 °C for 2 h, the absorptance and emittance (at 400 °C) of Al/NbTiN/NbTiON/SiO 2 and Al/NbTiSiN/NbTiSiON/SiO 2 multilayer coatings change from 0.934/0.13 and 0.931/0.12 to 0.538/0.14 and 0.922/0.13, respectively. Meanwhile the surface roughness increases from 18.3 and 7.9 to 41.5 and 14.7 respectively, as atomic force microscopy (AFM) shows. The Al/NbTiSiN/NbTiSiON/SiO 2 coating still has a high absorptance (0.910) and low emittance (0.13, at 400 °C) after ageing at 550 °C in vacuum for 100 h. It displays that Si-doping play an important role in the improvement of the thermal stability. [ABSTRACT FROM AUTHOR]

For the applications in solar thermal power, the preparation and optimization of an Al/NbMoN/NbMoON/SiO 2 multilayer solar selective absorbing coating are carried out by combining experiments with optical simulation. A series of NbMoN and NbMoON single layers are deposited by magnetron reactive sputtering method with different N 2 /O 2 gas flowing rates. And then their optical constants are obtained by fitting their reflection (R) and transmission (T) spectra in the wavelength range of 300–2500 nm using SCOUT software. These optical constants are used to design the Al/NbMoN/NbMoON/SiO 2 solar selective absorbing coating so as to get the ideal spectral selectivity, i.e. high α / ε ratio. According to the optical design of the coating structure, we prepared the all-layer coating, and the thickness of each layer was optimized until the best spectral selective properties are obtained. The experimental reflectance spectrum fits very well with the simulated result. The optimized solar absorbing coating deposited on stainless steel substrate exhibited high absorptance ( α =0.948) and low emittance ( ε =0.050) at 80 °C. It offers a good method to quickly reach the ideal spectral selectivity through optical simulation. The thermal stability of the coating is evaluated, and it exhibits a good thermal stability in vacuum at 400 °C. [ABSTRACT FROM AUTHOR]

Abstract: Mo–Al2O3 solar selective absorbing coating was deposited on stainless steel substrate by magnetron sputtering. The evaluation of high temperature stability indicates that the degradation of the optical properties is due to the diffusion and oxidation of single metal Mo in the ceramic Al2O3. Mo diffuses easily in Al2O3 layer and the interface between the double Mo–Al2O3 layers when aging temperature is above 400°C, which was observed by SEM and AES with etching depth. The thermal stability was improved significantly when a denser Mo–Al2O3 layer was obtained by optimizing the deposition parameters. [Copyright &y& Elsevier]

• A nanosecond pulse laser to remove rubber was conducted. • The influence before and after different laser cleaning conditions are analysed. • Thermal simulation of the surface temperature was analysed. • The quality improvement of laser rubber removal was studied. This paper utilizes a nanosecond pulse fiber laser to conduct rubber removal experiments on rubber laminated metal valves. The influence on surface roughness, metallographic structure and hardness of samples before and after different laser cleaning conditions are analyzed. Experimental results show that the laser has no significant effect on the substrate situation of the rubber laminated valves when it is immersed in water or sprayed with water. Through thermal simulation, the surface temperature when using wet-type laser cleaning is lower than that of using dry-type laser cleaning, and there is no significant effect on the substrate. Therefore, wet-type laser cleaning is appropriate for rubber laminated metal valves. [ABSTRACT FROM AUTHOR]

• Signature-tagged transposon mutagenesis based on Tn4351 was developed in R. anatipestifer. • Seventeen tagged Tn4351 random mutation libraries of strain WJ4 were constructed and screened for survive using a duckling infection model. • Twenty mutants that could not be recovered from the infected ducklings, were identified, and 17 mutated genes were identified. • The virulence of mutants 16-284, 7-295, 24-231, 9-232 and 19-214 were significantly attenuated compared to that of the wild-type WJ4. Riemerella anatipestifer causes epizootic infectious disease in ducks, geese, turkeys and other birds, and serious economic losses especially to the duck industry. However, little is known about the molecular basis of its pathogenesis. In this study, signature-tagged transposon mutagenesis based on Tn4351 was developed in R. anatipestifer to identify genes essential for survival and pathogenesis. Seventeen tagged Tn4351 random mutation libraries of the R. anatipestifer strain WJ4 containing 5100 mutants were screened for survive using a duckling infection model. Twenty mutants that could not be recovered from the infected ducklings, were identified, and 17 mutated genes were identified by inverse PCR or genome-walking PCR. Of these genes, FIP52_03215, FIP52_04350 and FIP52_09345, were inserted into two mutant strains, and FIP52_03215 and FIP52_03175 were found exclusively on the chromosome of serotype 1 R. anatipestifer strains. Twelve out of 17 genes encoding for proteins were predicted to be involved in amino acid, nucleotide, coenzyme, or lipid transport and metabolism, one gene was predicted to be involved in signal transduction, one gene was predicted to be involved in DNA replication, recombination and repair, the other three genes had an unknown function. Animal experiments showed that the virulence of mutants 16-284, 7-295, 24-231, 9-232 and 19-214 were significantly attenuated compared to that of the wild-type WJ4. Moreover, the median lethal dose of mutant 16-284 was greater than 1010 CFU, and its virulence to ducklings was partially restored when it was complemented with the shuttle expression plasmid pRES-FIP52_09345. The results in this study will be helpful to further study the molecular mechanisms of the pathogenesis of R. anatipestifer infection. [ABSTRACT FROM AUTHOR]

Abstract: The magnetic and electronic transport properties of the antiperovskite Mn3NiN thin film deposited on quartz substrate using magnetron sputtering were investigated. The film shows a (100) preferred orientation. It is worthwhile noting that a positive magnetoresistance (MR) effect was found in the whole measured temperature region and the maximum MR value by 31% was obtained at about 300K under 2T. On the other hand, when cooling from room temperature, a spin-glass behavior was also observed in the Mn3NiN film and the Tb shifted to lower temperature with increasing external magnetic field. In contrast to the bulk counterpart, the temperature dependent resistivity of the film shows a semiconductor-like behavior. [Copyright &y& Elsevier]