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We investigated the effect of Fe 50 Pd 50 nanoparticle addition on the crystal structure and superconductivity of Bi 1. 6 Pb 0. 4 Sr 2 Ca 2 Cu 3 O 10+δ compounds. Pure and Fe 50 Pd 50 -added Bi 1. 6 Pb 0. 4 Sr 2 Ca 2 Cu 3 O 10+δ samples with different additional contents were prepared by the solid-state reaction technique. Crystal structure and surface morphology of the fabricated samples revealed the formation of Bi-2223 and Bi-2212 superconducting phases. The critical temperature (T c) of the Fe 50 Pd 50 -added samples was lower than that of the pure one. In comparison with the pure sample, magnetization J c was clearly enhanced for the samples with the addition of Fe 50 Pd 50 having stronger magnetic properties. The enhancement in J c was possibly explained by the fact that Fe 50 Pd 50 nanoparticles served as effective pinning centers. Dominant pinning mechanisms of all samples were analyzed to be δl pinning by the collective pinning theory. The geometry of artificial pinning centers was identified to be normal core volume and point-like pinning by using the Dew–Hughes model. [ABSTRACT FROM AUTHOR]

In this paper, porous single-crystal diamond with boron doping were synthesized by adding TiB 2 to the Fe–Ni–C system at a pressure of 5.6 GPa and a temperature of 1360 °C. The boron and nitrogen impurities were investigated in depth along with the surface defects of the diamonds. The results indicate that when the TiB 2 content was within the range of 0–10 wt%, an increase in the doping concentration of TiB 2 can lead to a decrease in the nitrogen content and an increase in the boron content in the diamond, causing the crystal color to transition from yellow to pale yellow, pale yellow-blue, and black. When the TiB 2 content was within the range of 20–40 wt%, several triangular concave porous structures appeared on the crystal surface. With an increase in the TiB 2 addition, the side length of these triangular pits decreased from 2.85 μm to 1.09 μm, while their depth decreased from 590 nm to 50 nm. The roughness of the crystal surface measured by Rq demonstrated values up to 145.302 nm. The results indicate that the size, depth, and density of the triangular defects can be adjusted by the amount of additive TiB 2. Our findings provide insights into the surface regulation and functionalization of boron-doped diamond single crystals. [ABSTRACT FROM AUTHOR]

The effect of long-term corrosion in water-oxygen atmosphere at 1350 °C on the organization of eutectic glass of the Y 2 O 3 –Al 2 O 3 –SiO 2 (YAS) system was investigated and the corrosion mechanism was analysed. As corrosion time increases, the surface crystals of glass-ceramics, especially cristobalite, is gradually consumed, resulting in a gradual increase in the roughness of the surface. Subsequently, the thermal expansion mismatch of corrosion products causes internal stresses, which result in cracks and accelerate corrosion of the glass-ceramics. It is worth mentioning that this eutectic composition showed an unknown X-phase after 100 h of corrosion, and its structure was reasonably predicted. [ABSTRACT FROM AUTHOR]

Understanding how the morphology and microstructure of secondary particles are affected by pH is essential to design spherical and dense hydroxide aggregates as precursors of high-performance cathode materials for lithium-ion batteries. To investigate the interplay between thermodynamic reaction conditions and the physicochemical properties of precursors, a chemical equilibrium model is used to describe the evolution of metal ammonia complexes. Furthermore, the formation and growth of aggregates are studied by monitoring the changes in surface morphologies and crystal structures of precursors at different reaction times. As the pH value varied, two notable phenomena occurred during crystal growth: the fast growth of grains in the early stage as the pH decreased and the layered growth of grains in the later stage with increased pH values. Such findings could be explained from the following two perspectives. First, the decrease in pH causes a significant increase in the complex ion concentration, thereby facilitating the growth of crystals along the [010] direction. Second, an increase in pH generally accelerates deprotonation of the crystal surface, thus strengthening the adsorption of complex ions on the crystal surface and promoting layer-by-layer growth of primary grains along the [001] direction. [Display omitted] • The effect of pH on crystal growth is investigated by modeling and experimental. • The weak hydrogen bonding dominates the adsorption of complexes on (001) facet. • The deprotonation strengthens the adsorption of complexes on crystal surface. [ABSTRACT FROM AUTHOR]

Zirconia nanorods and polyhedral particles were prepared using the molten-salt method. The effects of the LiF dosage on the ZrO 2 crystal morphology were studied using XRD combined with Rietveld refinement, FE-SEM combined with EDS, FTIR, Raman spectroscopy, and high-temperature microscopy. The results show that the ZrO 2 obtained with LiF is in the monoclinic phase. ZrO 2 nanorods were synthesized at low LiF dosages. Polyhedral ZrO 2 particles were synthesized, and the ZrO 2 crystal planes (100) and (200) were exposed to a high LiF dosage. LiF promoted the dissolution of ZrO 2 and was adsorbed onto the ZrO 2 crystal surface. This work provides a new strategy for controlling morphology and crystal surface exposure. [ABSTRACT FROM AUTHOR]

We report a facile method to enhance the photoluminescence of 6Y–ZrO 2 : Er3+ translucent ceramics prepared via the vacuum sintering technique by introducing Ag. Ag atoms could be incorporated into the host at high temperatures; these atoms partially precipitated to form Ag nanoparticles during cooling. The intensities of green up-conversion, 1.5 and 2.7 μm emissions under 980 nm excitation, and the green down-conversion luminescence upon 377 nm excitation were improved via co-doping with Ag due to the modification of the local crystal field and the surface plasmon resonance effect. Based on the fluorescence intensity ratio of 2H 11/2 → 4I 15/2 versus 4S 3/2 → 4I 15/2 , 6Y–ZrO 2 : 1 mol%Er3+, 0.67 μmol%Ag exhibited the maximal relative sensing sensitivity of 1.12 %K−1, which could be applied as a potential thermometer with good sensitivity. The present work sheds light on how to simultaneously enhance the emission intensity and thermal sensitivity of Er3+ in ceramics. [ABSTRACT FROM AUTHOR]

High-Ni layered LiNi x Co y Mn 1-x-y O 2 cathode materials with a high discharge capacity have been extensively applied in many fields. However, the cycle life of these materials limits their wide applications because of their severe polarisation and large irreversible capacity. In this study, the first-principles calculation was used to determine changes in the conductive properties of LiNi 0.83 Co 0.11 Mn 0.06 O 2 (NCM831) followed by doping with Nb. The theoretical results were used to increase the performance of the cathode material by surface coating LiNbO 3 and doping Nb5+ into the crystal lattice of LiNbO 3. The results show that the first cycle discharge capacities of NCM831 and its modified 1% Nb 2 O 5 (NbO-1) at 1.0 C are 189.72 and 207.12 mAhg-1, respectively, while doping of the crystals with an appropriate Nb5+ ratio (0.25%:100%, 0.5%:100%, 0.75%:100%, and 1.0%:100%) enhanced their discharge capacity. The LiNbO 3 nano-coating decreased the polarisation and charge transfer resistance of NCM831. The bare NCM831 and NbO-1 presented metallic properties, with a fairly large Li + diffusion coefficient. Nb5+ doping and LiNbO 3 coating affected the crystal structure and surface morphology of NCM831 before and after cycling. These results provide insights into the experimental applications of first-principles calculation for Ni-rich layered LiNi x Co y Mn 1-x-y O 2 cathode materials. [ABSTRACT FROM AUTHOR]

NASICON-type Na 3 V 2 (PO 4) 2 F 3 (NVPF) is proposed to be a potential cathode material for sodium-ion battery because of its good structural stability, relatively high capacity and voltage platform. Nonetheless, the poor-rate performance, resulting from its low conductivity, has become a massive obstacle to its practical application. In this work, carbon coating together with morphology controlling were introduced to solve the issue of NVPF. This experiment used a hydrothermal method to prepare Na 3 V 2 (PO 4) 2 F 3 @C (NVPF@C) and explored the impact of surfactants (polyvinylpyrrolidone (PVP)) on the positive material performance of sodium-ion battery. Through various characterisation, NVPF@C compared its performance with that of untreated products, and verified that appropriate surfactant modification could enhance the performance of the electron conduction and sodium ion diffusion, thus effectively improved the performance of NVPF. Through comparison, it was found that appropriate surface modification with PVP can achieve the effects of specific crystal surface exposure and clusters of porous micron ball structure, and improve the electrochemical performance of NVPF best. Under the charge and discharge ratio of 0.2C, its initial reversible capacity was 127.8 mA h g−1. After 100 cycles, its discharge capacity was 106.1 mA h g−1, and the cycling retention rate reached 82.8%. Compared to the original NVPF, its performance has been dramatically improved. [ABSTRACT FROM AUTHOR]

Ni-rich materials, as one type of cathode materials for next-generation lithium-ion batteries, suffer from poor cycling stability due to severe structural degradation and surface deterioration. Lattice doping is an effective method to stabilize crystal structures, yet it has little effect on inhibiting surface side reactions. Herein, we demonstrate a strategy that can tailor the distribution of doping element Al in the entire secondary sphere in a controllable way to simultaneously stabilize the crystal structure and surface of the cathode material. The strategy takes advantage of the interdiffusion of elements at the solid-solid interface formed by aluminum-containing species that uniformly cover the surface of the Ni 0.8 Co 0.1 Mn 0.1 (OH) 2 precursor at a high temperature. The extent of Al doping in the materials can be properly regulated by the amount of aluminum-containing species to generate uniform doping, gradient doping, and gradient doping with a thin Al coating layer. As a result, the Al gradient-doped cathode material exhibits excellent capacity retention of 81.9% after 500 cycles at 2C, which is much higher than the capacity retention of 54.3% for the pristine counterpart. [ABSTRACT FROM AUTHOR]

Alloying strategy in quantum dots (QDs) has shown great advantages in regulating photophysical properties and improving the performance of photovoltaic devices. Typically, CdSeTe alloy QD is proved to be a superior photosensitizer, and has presented great potential in constructing high-efficient quantum dot solar cells. However, systematic analysis for the carrier dynamics is still lacking. In this paper, the carrier dynamics within CdSeTe colloidal QDs and at the TiO 2 /CdSeTe interface has been studied in detail by transient absorption (TA) spectroscopy and photoluminescence (PL) spectroscopy. TA results show that the gradient component of CdSeTe QDs leads to different electronic transition properties distinct from those of their parent binary components. Temperature-dependent time-resolved PL spectra for the CdSeTe/TiO 2 demonstrate that PL lifetime decreases from 13.54 to 3.08 ns with increasing temperature from 10 to 300 K. Moreover, the electron transfer rate increases more quickly when temperature exceeds 250 K. In addition, it is confirmed that the crystallization characteristics of TiO 2 have a significant impact on the interfacial carrier dynamics. A faster electron transfer from CdSeTe QDs to rutile TiO 2 (R–TiO 2) has been obtained than that to anatase TiO 2 (5.65 × 108/s vs 3.21 × 108/s). Both QDs adsorption and electron transfer properties closely dependent on the crystal orientation of R–TiO 2 single crystal. CdSeTe QDs attached to the (100) R–TiO 2 single crystal surface achieve the fastest electron transfer rate than other R–TiO 2 orientations of (111), (110) and (001). [ABSTRACT FROM AUTHOR]

Bioactive glasses are mostly utilized as bone and dental implants. However, these biomaterials cause immunogenic response even in absence of immune stimulating signals. Therefore, there is a need to develop a biomaterial that would be immunologically inert and possesses beneficial biological effects depending upon the pathological condition. In this study, barium doped bioactive glass (BaBG) and 45S5 were synthesized in the nanometer range using the sol-gel process and the BET-specific surface area was assessed. The in-vitro bioactivity of BaBG and 45S5 was examined in the simulated body fluid (SBF). Hydroxyapatite crystals formed on the surface were evaluated using FTIR, X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy-dispersive X-Ray spectroscopy (EDX), and pH changes of SBF. The doping of barium in bioactive glasses showed biocompatibility as the hemolytic index was within the permissible limit for biomedical agents. BaBG and 45S5 increased the percentage of cell proliferation without producing any cytotoxic effects on C6 and K562 cells. Moreover, BaBG showed coordinated horizontal cell movement in scratch assay which is a gold standard for the regeneration of injured tissues. Intriguingly, for the first time we reported that the incorporation of barium significantly reduced the LPS-induced elevation of interleukin-6 (IL-6) and tumor necrosis factor- α (TNF-α) in C6 cells. Simultaneously, BaBG also elevated IL-10 and hence showed anti-inflammatory properties. Therefore, based on the biocompatibility, cytocompatibility, and regenerative tendency, BaBG can be used for therapeutic purposes where inflammation restricts the use of biomaterials. Image 1 • Sol-gel method was employed to synthesize bioactive glasses and was characterized. • BaBG and 45S5 exhibited biocompatible hydroxy carbonated apatite formation. • They did not affect the proliferation of C6 and K562 cells and are cytocompatible. • Incorporation of barium ameliorated the percentage wound recovery in scratch assay. • Doping Ba2+ exhibited better anti-inflammatory effect in LPS-induced inflammation. [ABSTRACT FROM AUTHOR]

In the present work, we report a high activity Ti 3 C 2 MXene nanosheet/TiO 2 (Ti 3 C 2 /TiO 2) composite photocatalyst synthesized by a solvent-thermal method using tetrabutyl titanate (Ti(OBu) 4) as Ti source and HF as assistant. The Ti 3 C 2 /TiO 2 composites were characterized by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV–Vis spectroscopy (UV–vis), fluorescence spectrometer (PL) and N 2 adsorption-desorption. The photocatalytic performance of the Ti 3 C 2 /TiO 2 composites was explored for the degradation of rhodamine B (RhB) under visible light irradiation. The results showed that more highly-active (001) crystal surfaces of TiO 2 were exposed in the Ti 3 C 2 /TiO 2 composites assisted by HF. The composite consisted of TiO 2 microspheres and multilayer Ti 3 C 2 exhibited optimal photocatalytic performance with relatively large specific surface area, large photocurrent and much lower impedances as compared to commercial TiO 2 (P25) and pure TiO 2. The optimized sample exhibited a degradation rate of 93.7% in 60 min, which was 20.5-fold higher than that of P25. The addition of the Ti 3 C 2 effectively increased the lifetimes of the Ti 3 C 2 /TiO 2 composites and suppressed the recombination of the electron-hole pairs. The density functional theory (DFT) calculations also revealed that the photogenerated electrons in the composites flowed from TiO 2 to Ti 3 C 2. The Schottky barrier at the TiO 2 –Ti 3 C 2 interfaces effectively inhibited the electronic reflow to TiO 2. The as-developed new Ti 3 C 2 -based complex with high photocatalytic activity under visible light irradiation might have effective and feasible application in the treatment of dye-containing wastewater. [ABSTRACT FROM AUTHOR]

Sodium-ion battery as an attractive energy storage system is acknowledged as alternative to lithium-ion battery on account of their extensive resources and low price. NaTi 2 (PO 4) 3 is considered as an excellent electrode material in sodium-ion battery due to open three-dimensional crystal channels for ion diffusion. In this work, reasonable crystal design of Zr doping and surface modification of carbon coating strategy was employed to promote the sodium storage performances of NaTi 2 (PO 4) 3 electrode. A series of NaTi 2-x Zr x (PO 4) 3 /C (x = 0.05, 0.1, 0.15) composites with core@shell structure were synthesized through an easy sol-gel route, and were applied as electrode for sodium ion battery. The result shows that the crystal type of all samples is relatively pure. However, the dispersion of Zr doped samples are significantly improved compared to the blank sample. Among all the samples, NTP-Zr-0.1 (NaTi 1.9 Zr 0.1 (PO 4) 3 /C) demonstrates the best charge/discharge performances. It delivers the discharge capacities of 206.3 mA h g-1 at 40 mA g-1 and 79.2 mA h g-1 at 2000 mA g-1, while those of NTP are 116.2 and 26.9 mA h g-1, severally. Superior electrochemical performance of NTP-Zr-0.1 is probably ascribed to the carbon coating structure, good dispersion, and lattice volume increase, further accelerating the transfer of electron and sodium ion. This study implies that carbon coating and Zr doping are facile and efficient strategy for promoting performances of NaTi 2 (PO 4) 3 /C composite. [ABSTRACT FROM AUTHOR]

The mechanism of different exposed crystal surfaces on dielectric polarization characteristics is of great significance to understand the interface impedance matching. In this work, the controllable preparation of titanium carbide (TiC) with different exposed crystal surface was realized by adjusting the reaction atmosphere, which is based on the growth rate and surface energy of different exposed facets. TiC(100)/graphite and TiC(111)/graphite interfaces are found in the truncated octahedral TiC/C nancomposites, while only TiC(100)/graphite interface exits in the cubic nanocomposites. Experimental conclusion companied by theoretical calculations identify that dielectric loss capacity is improved by the strong localization of polarized charge at TiC(111)/graphite interface. Due to the enhanced permittivity, dielectric loss ability and absorption coefficient, the truncated octahedral TiC@C nanocomposites exhibit the reflection loss of −45.1 dB and the effective frequency bandwidth of 5.3 GHz at 2.1 mm. The proposed interfacial modulation strategy can provide a reference for designing high efficiency microwave absorber. [ABSTRACT FROM AUTHOR]

A series of Al compound-coated LiNi 0.5 Mn 1.5 O 4 materials is synthesized by a facile calcination process under different temperatures. The effect of calcination temperature on physicochemical properties and electrochemical performance of Al-coated LiNi 0.5 Mn 1.5 O 4 materials are investigated by using the X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The electrochemical properties of as-prepared materials showed that the C-500 sample (calcined at 500 °C) has excellent cycling performance and rate capability. Meanwhile, even at high operation temperature (55 °C), the capacity retention is 88% after 50 cycles at a rate of 0.5 C. Moreover, the crystal structure and surface morphology of C-500 sample after 200 cycles are also studied. All the results indicated that the composite coating layer with Al 2 O 3 and LiAlO 2 can not only reduce the side reactions at the electrode and electrolyte interface, but also provide an effective channel for the diffusion of Li+ in the charge/discharge process. [ABSTRACT FROM AUTHOR]

A low-temperature synthesis of α-alumina was studied using a flux consisting of salts and additives. Al(OH) 3 was used as a precursor for the preparation of alumina; NaCl–KCl, NaCl, Na 2 SO 4 and K 2 SO 4 were used as the salts in the flux; and cryolite (Na 3 AlF 6) was used as an additive. Using a flux consisting of Na 3 AlF 6 with each salt confirmed that a phase change to α-alumina was possible even at a low temperature of 600 °C. Among the salts used, NaCl was the most effective. The flux with NaCl and Na 3 AlF 6 could produce highly pure and highly crystalline platelet α-alumina crystals at 700 °C. Herein, NaCl exhibited interfacial activity during the phase change process and contributed to the growth of the α-alumina plate-like crystals with a clear crystal surface. Na 3 AlF 6 was found to contribute significantly to the formation of crystal nuclei for the initiation of the phase change to α-alumina even with the addition of small amounts, namely, a 0.02–0.03 M ratio (Na 3 AlF 6 /Al(OH) 3). [ABSTRACT FROM AUTHOR]

In this study, the effect of the annealing atmosphere (N 2 –CO and pure N 2 atmosphere) on the crystal quality, surface morphology, and surface O content of the annealed AlN buffer layers was studied. The FWHM of the (0002) plane of an XRD rocking curve showed that the screw dislocation density of the as-grown AlN film can be reduced by annealing in both N 2 –CO and pure N 2 atmosphere. The AlN film showed an improvement in crystal quality under pure N 2 annealing atmosphere. As annealing the AlN buffer layer improves the crystal quality, surface roughness, and surface O content of the AlN film, it should be well controlled for the subsequent growth of III-nitride layers. The surface oxidation that occurred on the AlN films during annealing in N 2 –CO atmosphere resulted in an increase in surface O content and surface roughness of the AlN films, which is undesirable for the subsequent growth of III-nitride layers. We observed that the surface O content (in the depth of 2-nm) of all annealed AlN films was reduced in the N 2 annealing atmosphere, which could be due to the O outgassing from the AlN surface to the pure N 2 annealing atmosphere. The O outgassing of the surface O content in the AlN surface layer was related to the volume of space in the annealing setups. However, a large volume of annealing space under pure N 2 gas flow resulted in higher thermal decomposition on the annealing AlN films, leading to pits forming on the annealed AlN surface and a smearing of the original step-terrace structure. Therefore, we found that there is an optimal annealing atmosphere space in maintaining the original surface morphology and achieving low surface O content in the annealed AlN film. [ABSTRACT FROM AUTHOR]

Graphite carbon nitride (g-C 3 N 4) is an appealing metal-free photocatalyst for hydrogen evolution, but the potential has been limited by its poor visible-light absorption and unsatisfactory separation of photo-induced carriers. Herein, a facile one-pot strategy to fabricate carbon self-doped g-C 3 N 4 composite through the calcination of dicyanamide and trace amounts of dimethylformamide is presented. The as-obtained carbon self-doped catalyst is investigated by X-ray photoelectron spectroscopy (XPS), confirming the substitution of carbon atoms in original sites of bridging nitrogen. We demonstrate that the as-prepared materials display remarkably improved visible-light absorption and optimized electronic structure under the premise of principally maintaining the tri- s -triazine based crystal framework and surface properties. Furthermore, the carbon doped g-C 3 N 4 composite simultaneously weakens the transportation barrier of charge carriers, suppresses charge recombination and raises the separated efficiency of photoinduced holes and electrons on account of the extension of pi conjugated system. As a result, carbon self-doped g-C 3 N 4 exhibits 4.3 times greater photocurrent density and 5.2 times higher hydrogen evolution rate compared with its bulk counterpart under visible light irradiation. [ABSTRACT FROM AUTHOR]

Triple layers of TiO 2 /TiN/TiO 2 with different TiN thicknesses have been deposited using D.C. reactive magnetron sputtering on heated Si (100) and glass substrates. In this study, the effect of TiN thicknesses on different properties have been conducted. Analysis of XRD and SEM demonstrated the enhancement of the crystal structure and surface morphology with suitable TiN thickness. The optical studies elucidated the increase and the confinement of both reflectivity and refractive index with TiN thickness whilst the opposite was observed in the transparency and the optical band gap. The Essential Macleod software is used to design the optical coating hence predicting the extent of matching between theory and experiment. The self-cleaning tests demonstrated the quick transform from hydrophobic to superhydrophilic that is highly sensitive to the surface nature as well as the thickness of TiN layer. This newly designed system can be exploited as heat mirrors, dichroic filters and in self-cleaning applications. [ABSTRACT FROM AUTHOR]

Glass samples were polished and coated with a 10 nm thick silver layer. Both, silver-coated and uncoated samples were thermally treated at 750 °C for 4 h or at 790 °C for 2 h. In both types of samples, the phase Ba 0.5 Sr 0.5 Zn 2 Si 2 O 7 crystallized, which exhibits a negative thermal expansion. After thermal treatment, the uncoated sample showed a low number of crystals at the surface and even less if a crystallization temperature of 790 °C was supplied. By contrast, the silver-coated sample exhibited much more crystals at the surface. The number of crystals did not considerably depend on the crystallization temperature. The crystals in the silver-coated sample grew into the bulk with a highly unique orientation. Their crystallographic c-axes are perpendicular to the surface. The orientation of the crystals of the uncoated sample was not as strict. The uncoated sample showed numerous cracks, while the silver-coated sample did not show any cracks. In a first step, the metallic silver layer is dewetted and forms a structure composed by silver islands. During further heating, the islands are oxidized to Ag 2 O, which diffuses in the glass. Since Ag 2 O is incorporated in the glass as a network modifier, the network connectivity of the glass and hence also T g decreases. This results in a higher nucleation rate in surface near regions. [ABSTRACT FROM AUTHOR]

The effects of modification temperature and time on polyacrylonitrile (PAN) fibers under various concentrations of KMnO 4 were studied. Wettability, colouration, chemical structure (Fourier transform infrared spectroscopy), crystal structure (X-ray diffraction), stack domains (D), interlayer spacing (d), microscopic structure (Scanning electron microscopy) and elemental content (energy dispersive spectroscopy) were analysed. Aside from its good hydrophilicity, KMnO 4 at 2 and 4 wt% are beneficial to the modification of PAN fibers. The colouration of the fiber at 80 °C is the most obvious. The clear peak of the pre-oxidised fibers at 2340 cm−1 corresponds to the conjugated structure of MnO 4 –C N. At 4 wt%, the degree of pre-oxidation is too high and the main infrared peak disappears. M 2, 30 has a minimum D of 9.320 nm and 8.258 nm at 2θ = 16.883° and 2θ = 29.673°, respectively, and the fiber crystals are the finest. At a content of 4 wt%, the fibers are axially cracked and crystals appear on the surface. M 2, 30 and M 2, 60 have a close percentage of C element, whereas M 2, 30 has a lower percentage of Mn element. The best modification conditions of KMnO 4 are 2 wt%, 80 °C and 30 min. [ABSTRACT FROM AUTHOR]

In this study, Al-Si/Al 2 O 3 core-shell structured particles were fabricated via pressurized steam corrosion for 1 h followed by heating for 3 h at 1100 °C. After steam corrosion, a layer composed of disordered crystals covered the surfaces of the Al-Si alloy particles. After heating, Al-Si/Al 2 O 3 core-shell structured particles with complete shells were prepared. The thickness of the shell was approximately 2 μm, and it enclosed the Al-Si alloy core. The shell exhibited excellent thermal stability because, even at 1100 °C, the mass gain ratio of the encapsulated particle was less than 0.5%. Scalloped patterns of alumina were formed by the oxidation of Al, which was inlaid through and upon the alumina shell. The shell formation mechanism suggested that the α-Al 2 O 3 shell resulted from the combination of the decomposition of surface Al(OH) 3 crystals and the oxidation of Al from the core. [ABSTRACT FROM AUTHOR]

TiO 2 @carbon flexible fiber was prepared by combining electrostatic spinning technology and hydrothermal synthesis method. The XRD, SEM, TEM and Zeta potential techniques were used to characterize the phase, microstructure and surface charge properties of the samples. The growth mechanism of TiO 2 nanoarray on carbon flexible fiber with different morphologies was studied, and the dye adsorption capacity of the samples was evaluated by methylene blue (MB) degradation effect. The results showed that proper doping amounts of TiO 2 particles improved the flexibility and the hydrophilic property of carbon fiber significantly, which was conducive to the deposition and growth of TiO 2 on the carbon fiber. With the increase of hydrothermal time, the TiO 2 nanoarray grew denser gradually along the [110] crystal surface. The negative charge on the surface of carbon fiber increased, which was benefited to the removal of MB. The dye adsorption capacity of TiO 2 @carbon fiber was resulted from the synergistic effect of physical adsorption (carbon fiber) and photocatalysis (TiO 2) process. [ABSTRACT FROM AUTHOR]

Abstract the Brown glaze porcelain is one of the main production for the Yaozhou kiln in the Northern Song Dynasty (960–1127 A.D). To clarify the colouring mechanism of the brown glaze is a key to understand the technology development of the Yaozhou kiln in the 11th century. In order to determine the production process and its features, the brown glaze porcelain samples from Yaozhou kiln were analyzed by optical microscope, SEM, Micro-energy disperses X-ray fluorescence, X-ray diffraction and X-ray absorption fine structure. The results show that the brown glaze has two layers with different colours: the surface of the glaze is brown and the bottom is black; regarding the composition, the surface layer of the glaze contains much more iron than the bottom layer, and the amount of Titanium is high in both parts of the glaze. The crystals concentrated on the surface of the glaze, in addition to alpha -Fe 2 O 3 and Fe 3 O 4 crystals, the epsilon -Fe 2 O 3 crystals which are rarely found also formed on the surface glaze. The brown colour of the glaze is mainly contributed by the several kinds of iron oxides crystals. The red ferric oxide crystals mixed with black ferroferric oxide crystals to present brownish effect. The black bottom glaze reinforce the brown colour. The special brown glaze not only needs the iron rich raw materials but also requires a special firing process, particular to slow down the cooling procedure to create appropriate condition for crystallization. The later kilns of 13th −18th centuries used the similar technology to produce the brown or purple gold porcelain. The study revealed that the Yaozhou kiln is one of the origins of the brown glaze for both aesthetics and technology. [ABSTRACT FROM AUTHOR]

Phase pure SnO 2 powder, containing 0.25 wt% Sb 2 O 3 and 5 wt% Pd was synthesized by sonication assisted simultaneous precipitation method. The as-prepared dry powder and those calcined at various temperatures (200–1000 °C) were characterized by thermal analysis, x-ray diffraction (XRD), transmission electron microscopy (TEM) and surface area (BET) measurements. The effect of calcination temperature on morphology and crystal structure was investigated. The characterization results were employed to rationalize the catalytic sensing behavior towards n-butane gas of nanocrystalline SnO 2 based material incorporated into a thick film device, which detects gas molecules and produces an electrical signal with a magnitude proportional to the concentration of the gas. The powder calcined at 200 °C, having the lowest particle size (~14 nm) exhibited the maximum sensitivity (~96%) at 400 °C operating temperature with very fast response and recovery times suggesting their suitability for development of butane sensors/monitors. [ABSTRACT FROM AUTHOR]