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The tensile properties and microstructure of hot extruded GW84 alloy stretching at 200 °C, 250 °C and 300 °C were investigated. The results showed that the alloys had excellent high temperature mechanical properties, when stretching at 250 °C, the ultimate tensile strength of alloy reached peak value, 393 MPa, and the tensile strength stretching at 300 °C reached 354 MPa. During high temperature tensile process, the microstructure markedly changed, which is not recognised in previous researches. Stretching at 200 °C, the precipitate phase was still metastable β′ phase. However, when stretching at 250 °C, the nano β′ precipitate transformed into nano β phase (β′ → β), and the precipitation mechanism is mainly inoculation nucleation of β phase. When stretching at 300 °C, the number of β precipitates increased significantly at triangular grain boundaries, which grew up to sub-micron particles, and precipitation mechanism is mainly growth and coarsening.

Siniperca chuatsi feeds on live fry throughout their life. The sustainable development of its farming industry has urgently necessitated the development of artificial diets to substitute live baits. It has been demonstrated that gut microbiota assists in feed adaptation and improves the feed conversion rate in fish. Therefore, this study aimed to understand the potential role of intestinal microorganisms in the domestication of S. chuatsi with a compound diet. Accordingly, we performed 16S rRNA sequencing of the gut microbial communities in S. chuatsi groups that were fed a compound diet (including large and small individuals) and live baits. A total of 2,471 OTUs were identified, and the large individual group possessed the highest number of unique OTUs. The α-diversity index of the gut microbiota in groups that were fed a compound diet was significantly higher (p < 0.05) than that in the live bait group. There were no significant differences in the α-diversity between the large and small individual groups. However, relatively higher numbers of Lactococcus, Klebsiella, and Woeseia were observed in the intestines of the large individual group. Prediction of the metabolic function of the microbiota among these three fish groups by Tax4Fun revealed that most metabolic pathways, such as glycan metabolism and amino acid metabolism, were typically more enriched for the larger individuals. The results indicated that certain taxa mentioned above exist in large individuals and may be closely related to the digestion and absorption of compound diets. The present study provides a basis for understanding the utilization mechanism of artificial feed by S. chuatsi.

Conversion of calcium carbonate (calcite; CC) to hydroxyapatite (HAp) was examined when the CC particles of sub μm size were soaked at 37 °C for up to 10 d in 0.15 M K2HPO4 (20 ml), whose pH was set to 3–12. Here, the solution contained amino acids, such as glutamine (Glu), arginine (Arg), and glycine (Gly), and their content varied from 0–1.0 g per ml of solution. From the X-ray diffraction (XRD) intensity of the 104 and 211 diffractions of calcite and apatite, respectively, it was seen that the presence of the amino acids promoted the conversion. This was supported by the thermogravimetry (TG) results. The highest promotion was observed at 0.5 g addition of amino acids to the phosphate solution, while Glu showed the highest promotion among the amino acids and Gly the lowest. A scanning electron microscopy study indicated that petal-like HAp nano-crystallites covered the entire surface of the CC particles when they were soaked in the phosphate solution with 0.1 g or more of amino acid for 10 d. The XRD intensity ratio 104(CC)/211(HAp) indicated greater CC to HAp conversion in the solutions at pH 3 and 6 than in the more alkaline solutions. This was attributed to the dissolution of CC in the acidic solutions, which was confirmed by bubbling in these solutions.

Deep-trap persistent luminescent materials, due to their exceptional ability of energy storage and controllable photon release under external stimulation, have attracted considerable attention in the field of optical information storage. Currently, the lack of suitable materials is still the bottleneck that restrains their practical applications. Herein, we successfully synthesized a series of deep-trap persistent luminescent materials Y3Al5–xGaxO12:Ce3+,V3+ (x = 0–3) with a garnet structure and developed novel phosphor-in-glass (PiG) films containing these phosphors. The synthesized PiG films exhibited sufficiently deep traps, narrow trap depth distributions, high trap density, high quantum efficiency, and excellent chemical stability, which solved the problem of chemical stability at high temperatures in the reported phosphor-in-silicone films. Moreover, the trap depth in the phosphors and PiG films could be tailored from 1.2 to 1.6 eV, thanks to the bandgap engineering effect, and the emission color wa...

The application of Mg–air batteries is limited due to passivation and self-corrosion of anode alloys in electrolyte. In effort of solving this problem, the present work studied the influence of sodium silicate (SS)/sodium alginate (SA) on electrochemical behaviors of AZ61 alloy in NaCl solution by circle potentiodynamic polarization and galvanostatic discharge. The corrosion morphology and discharge product were examined by scanning electron microscopy (SEM) and x-ray diffraction (XRD). Results have shown that sodium silicate/sodium alginate inhibitors have an apparent effect on the self-corrosion of AZ61 alloy without affecting its discharge performance. The discharge capacity and the anodic utilization for Mg–air battery in a 0.6 M NaCl + 0.01 M SS +0.04 M SA solution are measured to be 1397 mAhg−1 and 48.2%, respectively. Electrochemical impedance spectroscopy (EIS) and SEM investigation have confirmed that the sodium silicate/sodium alginate inhibitor can obviously decrease the self-corrosion of AZ61 alloy. SEM and XRD diffraction examinations suggest that the inhibiting mechanism is due to the formation of a compact and “cracked mud” layer. AZ61 alloy can be used as the anode for Mg–air battery in a solution of 0.6 M NaCl + 0.01 M SS +0.04 M SA.

In order to study the effects of La2O3 content and rolling on microstructure and mechanical properties of Mo-La2O3 alloys, Mo-0.5% (1%) La2O3 alloys were prepared by liquid-solid doping technique, subsequently rolled either by a single-direction rolling or a cross-rolling. As a result, three different materials were prepared for this study. After being annealed at 1800 °C, the single-directionally rolled Mo-1% La2O3 alloy shows the best mechanical properties in terms of strength, hardness, and sagging deformation among the three materials. This is attributed to the observation that the alloy is only recovered with a microstructure of subgrains and dislocations. The single-directionally rolled Mo-0.5% La2O3 exhibits the worst mechanical property among the three materials. In this material, coarse grains, but no subgrains and dislocations, can be observed after annealing, indicating that it is fully recrystallized. For the cross-rolled Mo-1% La2O3 alloy, grains of dispersed sizes, but no dislocations, are visible after annealing, implying that this alloy is partially recrystallized. Accordingly, the mechanical property of this material is in between the other two materials. Thus, the mechanical properties of the three materials can be well understood based on OM, SEM, and TEM results. Overall, the single-directionally rolled Mo-1% La2O3 alloy possesses good mechanical properties and is more suitable for high-temperature applications.

Carbon dots (CDs) with tunable emission colors and multiple emission modes are highly desirable in advanced optical anti-counterfeiting. Some pioneering efforts to trigger additional long-lived emission modes, nevertheless, did not perfectly solve the issue of printability and color-tunability in practical applications. Herein, we developed an encapsulating-dissolving-recrystallization route for the synthesis of CD-based anti-counterfeiting inks, and accordingly realized blue, green, and red full-color afterglow emissions from these CD-based inks when printed on paper. The printed inks simultaneously possessed triple emission modes including fluorescence (FL), delayed fluorescence (DF), and room-temperature phosphorescence (RTP), among which the long-lived emissions (DF and RTP) could be selectively activated by using different excitation wavelengths. We believe that the proposed synthetic route in this work may promote the development of multicolor-encoded and multiple-mode-integrated optical anti-counterfeiting systems, and will expand the application of CD-based materials to the fields of sensing, photodynamic therapy and bio-imaging.

Titanium and its alloys are frequently employed in medical and dental clinics due to their good tissue compatibility, including commercially available pure Ti, Ti6A4V, or Ti-15Zr-4Ta-4Nb. Yet, they may behave very differently when in contact with our plasma because of their own chemical composition. The present study was designed to compare the in vitro behavior of highly pure Ti (>99.99%; hpTi) with those of the above titanium specimens when they were subjected to heating in air (HT), H2O2 and heating (CHT), and heating in air after forming grooves on the surface (GT). Since one of the measures of material-tissue compatibility has been in vitro apatite formation in artificial plasma, like simulated body fluid (SBF) of the Kokubo recipe, the apatite deposition in SBF on their surface and in their grooves were examined in terms of the X-ray diffraction, scanning electron microscopy, and energy dispersion X-ray analysis. The results showed that hpTi was as active in in vitro apatite deposition as the other reference titanium samples mentioned above. Moreover, GT specimens of hpTi induced apatite deposition on the platform of the grooves as well as in the grooves. Therefore, hpTi was concluded to have better activity, and to be clinically applicable.

This paper presents a new formula for calculating the hardness of metallic crystals, resulted from the research on the critical grain size with stable dislocations. The formula is H = 6 kG/[pi(1 - nu)e(eta)], where H is the hardness, k the coefficient, G the shear modulus, nu the Poisson's ratio, eta a function of the radius of an atom (r) and the electron density at the atom interface (n). The formula will not only be used to testify the critical grain size with stable dislocations, but also play an important role in the understanding of mechanical properties of nanocrystalline metals.