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The structural, electronic, optical, mechanical, lattice dynamics, and electronic transport properties of SrCu2O2 crystals were studied using first-principles calculations. The calculated band gap of SrCu2O2 using the HSE hybrid functional is about 3.33 eV, which is well consistent with the experimental value. The calculated optical parameters show a relatively strong response to the visible light region for SrCu2O2. The calculated elastic constants and phonon dispersion indicate that SrCu2O2 has strong stability in mechanical and lattice dynamics. The deep analysis of calculated mobilities of electrons and holes with their effective masses proves the high separation and low recombination efficiency of photoinduced carriers in SrCu2O2.

A highly efficient MgBi2O

The pyrochlore-type (Sr0.6Bi0.305)2Bi2O7 (SBO), containing Bi3+ and Bi5+ mixed valent states, was recently found to be used as a new visible light responsive photocatalyst. Novel SBO/SnO2 heterostructured composites were synthesized through a facile one-step hydrothermal method. The phase structure, morphology, chemical composition, and optical properties of the obtained samples were characterized by XRD, SEM, TEM, XPS, and UV-vis DRS. Compared to pure SBO and SnO2, the synthesized SBO/SnO2 composites exhibited significantly enhanced photocatalytic efficiency. The results indicated that the photoinduced holes and superoxide radicals play a dominant role and are the main reactive species during the degradation of Methylene Blue (MB) solution under visible light irradiation. Heterojunctions, formed in samples, directly contribute to the improvement of photocatalytic efficiency of SBO/SnO2 composites, since it not only broadens the light response range, but also accelerates the separation of photogenerated carriers.

The Au-Cu nanoalloys (NPs) were produced by NaBH4 co-reduction from the mixture precursor solution of component Au and Cu, under the protection of sodium citrate stabilizer. The Au-Cu NPs encapsulated in SiO2, Au5Cu5@SiO2 NPs, were then synthesized by the Stober method based on the obtained Au-Cu NPs. The microstructure and particle sizes were characterized by TEM observation. The phase transition temperature of Au-Cu@SiO2 was determined by DSC measurement. The surface tension, surface segregation and surface energy of Au-Cu NPs as a function of particle size and temperature were calculated by the theoretical model based on the thermodynamic properties of pure component of Au and Cu NPs, respectively. The thermodynamic parameters of Au-Cu system at various nanoscales were optimized on the basis of experimental and theoretical results in this work and previous results in literature. Based on the obtained the thermodynamic data set, the nano phase diagrams of the Au-Cu system at nanoscale were calculated, and the thermodynamic properties of Au-Cu nanometer system were obtained. The results show that the calculated results agree well with experimental work.

A honeycomb-structured Co–W–B composite was prepared by a simple chemical reduction process in an alcohol solution. The structure and morphology of the Co–W–B composite was characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The results indicate that the composite was mainly composed of oxides of Co, W, and B as a result of oxidation in air, and it was a suitable material for high-performance pseudocapacitors. Electrochemical tests indicated that the Co–W–B composite exhibited a specific capacitance of 306.3 F g–1 at a current density of 2 A g–1, which is much higher than that of a Co–B composite. Furthermore, the Co–W–B composite showed good stability, and the capacitance retained 89.2% of its initial capacitance after 2500 cycles. These results demonstrate that the honeycomb-structured Co–W–B composite is promising for use as an electrode material for supercapacitors.

We report on the size dependence of the Ag–Cu nano-alloy melting temperatures via differential scanning calorimetry (DSC) measurements of silica-coated Ag–Cu nanoparticles (NPs) and the thermodynam...

A new composite material based on copper–benzene-1,3,5-tricarboxylate (Cu–BTC) deposited on boron nitride nanotubes (BNNTs) in a hydrothermal process were investigated for methane (CH 4 ) sensing. The composite was characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The Cu–BTC deposited on the BNNTs had an average grain size of 80 nm. The sensing performance of the as-grown product was studied for different concentrations of CH 4 (20–200 ppm) at 150 °C. The results revealed that the Cu–BTC/BNNT composite exhibited high sensitivity and selectivity toward CH 4 . The good sensing performance of the composite was attributed to the high surface area and high affinity of Cu–BTC for CH 4 , which would allow the composite to act like a preconcentrator for CH 4 gas sensing.

Accelerating the separation efficiency of photoexcited electron-hole pairs with the help of binary heterojunction structure is considered to be a promising approach for significantly enhancing the photocatalytic hydrogen production performance of TiO2. Providing more (Sr0.6Bi0.305)2Bi2O7 (SBO) catalysts to function as active sites of TiO2, together with the ability to construct heterojunction structures, is highly desirable for photocatalytic hydrogen evolution and pollutant photodegradation. To achieve this goal, in this work, (Sr0.6Bi0.305)2Bi2O7/P25 (SBO/P25) binary heterojunction catalyst is formed in situ on the TiO2 surface by a simple one-step hydrothermal method. To evaluate the feasibility of SBO/P25 as a very efficient photocatalyst for degradation of MB and photocatalytic hydrogen evolution, a series of photocatalytic experimental studies were carried out. The experimental result indicated that the existence of heterojunction structure in the SBO/P25 nanocomposites improves the photocatalytic activity of P25. The photocatalytic performance of H2 evolution from water splitting and MB degradation for an optimal SBO/P25 photocatalyst reached 3.18 mmol g–1 h−1 and 3.42 × 10−2 min−1, respectively, which were 7.40 and 5.26 times higher than those of pure P25, respectively. The significantly improved catalytic capability on SBO/P25 is mainly ascribed to the enhanced visible light absorption and charge transfer in comparison with P25. In addition, SBO/P25 composites have excellent stability and recyclability, showing great potential for application in wastewater treatment and photocatalytic hydrogen evolution.

The Ag–Cu phase diagram at nanoscale was reassessed by CALculation of PHAse Diagrams (CALPHAD) method, considering the surface effect on the chemical potential of pure substance and excess Gibbs free energy of mixtures. According to the reported thermodynamic properties of pure Ag and Cu nanoparticles (NPs), and the measured melting eutectic temperatures of Ag8Cu2, Ag7Cu3, Ag6Cu5 to Ag5Cu5 NPs, respectively, obtained in the previous works, self-consistent thermodynamic parameters including the size effect were obtained by thermodynamic optimization. Using the obtained thermodynamic parameters, four Ag–Cu nano phase diagrams were constructed, and thermodynamic properties were calculated. It was indicated that the calculated Ag–Cu nano phase diagrams agreed well with experimental data.

A ternary composite of V 2 O 5 /carbon nanotubes/super activated carbon (V 2 O 5 /CNTs–SAC) was prepared by a simple hydrothermal method and used as a supercapacitor electrode material. The electrochemical performance of the electrode was analyzed using cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy, which were performed in 2 M NaNO 3 as the electrolyte. The V 2 O 5 /CNTs–SAC nanocomposite exhibited a specific capacitance as high as 357.5 F g −1 at a current density of 10 A g −1 , which is much higher than that of either bare V 2 O 5 nanosheets or a V 2 O 5 /CNTs composite. Furthermore, the capacitance increased to 128.7% of the initial value after 200 cycles, with 99.5% of the maximum value being retained after 1000 cycles. These results demonstrated that the V 2 O 5 /CNTs–SAC ternary composite is suitable for use as an electrode material for supercapacitors.

The interdiffusion behavior of bcc_B2 Ni–Al–Cu alloys at 1173 K was experimentally investigated on the basis of six groups of bulk diffusion couples. With the electron probe microanalysis technique and the Matano–Kirkaldy method, the composition-dependent mole-fraction interdiffusion coefficients and the interdiffusion fluxes in bcc_B2 Ni–Al–Cu alloys at 1173 K were determined. The reliability of the presently obtained interdiffusivities was verified by the thermodynamic stability constraints, comparison with the interdiffusion coefficients in boundary binary bcc_B2 Ni–Al alloys as well as numerical simulations based on Fick's second law.

A composite consisting of polyaniline (PANI) and reduced graphene oxide (rGO) was synthesized by in situ polymerization of the monomer aniline in the presence of rGO under acidic conditions. The PANI–rGO composite substrate was doped with Pd nanoparticles via chemical reduction. The resulting Pd–PANI–rGO nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy before it was utilized to fabricate a hydrogen sensor. Compared with the sensor based on PANI–rGO or PANI, the Pd–PANI–rGO sensor was highly sensitive and selective to hydrogen gas, with fast response time in air at room temperature. The significantly enhanced sensitivity resulted from the faster spill-over effect, dissociation of hydrogen molecules on Pd, and the high surface area of the PANI–GO composite. Based on its improved sensing properties, ease of fabrication, and stable operation, the Pd–PANI–rGO nanocomposite shows promise for high-performance hydrogen-sensing applications.

A ternary composite of polypyrrole (PPy), Prussian blue (PB), and graphene oxide (GO), PPy⿿PB⿿GO, was successfully prepared through spontaneous polymerization of pyrrole and formation of PB nanocubes on GO. The obtained nanocomposite was characterized by transmission electron microscopy, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The results indicate that the PPy-protected PB nanocubes were well dispersed on the GO. Electrochemical testing showed a specific capacitance of 525.4 F g ⿿1 at a current density of 5 A g ⿿1 in the potential range from ⿿0.2 to 0.6 V, obtained in an electrolyte of 1 mol L ⿿1 KNO 3 during the galvanostatic charge⿿discharge cycles, which is superior to the performance of binary cathode materials, including PPy⿿PB and PPy⿿GO nanocomposites. The as-prepared supercapacitor could retain a specific capacitance of 96% after 2000 cycles. It was confirmed that the three components⿿PPy, PB, and GO⿿led to the display of integrated electrochemical behavior and a resulting capacitor with enhanced performance. The significant enhancement in electrochemical performance of the ternary nanocomposite can be attributed to the synergistic effect of PPy-protected PB nanocubes dispersed on GO sheets with the pseudocapacitance from PB and PPy on the double-layer capacitance from GO.

A cobalt–boron/nickel–boron (Co–B/Ni–B) nanocomposite was synthesized in a two-step process by in situ reduction of nickel and cobalt salts. Characterization of the nanocomposite using X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller adsorption analysis showed that the Co–B nanoparticles were well dispersed on the Ni–B surface. Enlisted as a catalyst in the hydrolysis of ammonia borane (AB) for hydrogen generation (HG), the nanocomposite exhibited better catalytic activity than Co–B and Ni–B at room temperature; the HG rate was 1368.2 mL min−1 g−1 at 25 °C in a 1.5 wt.% AB solution, with a low activation energy of 33.5 kJ mol−1. The effect of the complexing agent (sodium citrate) on the nanocomposite's catalytic activity was also investigated. In addition, recycling tests showed that Co–B/Ni–B was still highly active and preserved 84% of its initial catalytic activity after 11 recover-and-reuse cycles.

Based on the recently developed pragmatic numerical inverse method for determining the composition-dependent interdiffusivities in a ternary system by using a single diffusion couple, high-throughput determination of the interdiffusivities in Cu-rich fcc Cu–Ag–Sn alloys at 1073 K was performed in the present work. The composition-dependent interdiffusivity matrices along the entire diffusion paths of five fcc Cu–Ag–Sn diffusion couples were obtained. The reliability of the interdiffusivities determined by the pragmatic numerical inverse method was first validated by Fick’s second law applied to numerical simulation of composition profiles and interdiffusion fluxes for each diffusion couple. The excellent agreement between the simulated results and the experimental data was obtained. In order to further validate their reliability, the traditional Matano–Kirkaldy method was employed to evaluate the interdiffusivities at the intersection point of the diffusion paths for every two diffusion couples. The good agreement between the interdiffusivities determined by the pragmatic numerical inverse method and those by the traditional Matano–Kirkaldy method was also observed. These facts indicate that the interdiffusivities determined by the pragmatic numerical inverse method are reliable.

In the present work, sixteen Mn–In alloys were investigated experimentally by means of thermal analysis and X-ray diffraction techniques. The temperatures of the invariant reactions and liquidus in the Mn–In binary system were determined. Based on the experimental results obtained in the present work and the critical review of the available experimental data from the published literature, the Mn–In binary system was assessed thermodynamically using the CALPHAD method. The solution phases including liquid, α-Mn, β-Mn, γ-Mn, δ-Mn and tetragonal_A6(In), are modeled by the substitutional solution model and their excess Gibbs energies are expressed with the Redlich–Kister polynomial. The intermetallic compound, InMn 3 , is treated as a stoichiometric compound. A set of self-consistent thermodynamic parameters obtained finally to describe the Gibbs energies of various phases in the Mn–In binary system can be used to reproduce well the phase equilibria and thermodynamic data.

The glass transition kinetics of melt-spun La65Al20Co15 amorphous alloy ribbons has been investigated using differential scanning calorimetry (DSC) technique with continuous heating of the sample at different heating rates. The dependence of the glass transition temperature (Tg) on the heating rate (β) has been determined by Lasocka’s relationship. The activation energy (E) of the glass transition has been obtained by employing Moynihan and Kissinger methods, respectively. It is found that the glass transition process cannot be described in terms of single activation energy. The variation of E with the extent of conversion (α) is further analyzed by using two iso-conversional methods. It is observed that the E of glass transition demonstrates a significant increase with the extent of conversion from amorphous to supercooled liquid phase of La65Al20Co15 metallic glass.

A Co–Zn–B/graphene nanocomposite was prepared by in situ reduction of cobalt and zinc salts on the surface of graphene (GP), and its catalytic performance in hydrogen generation (HG) by hydrolysis of NaBH4 was investigated. This composite exhibited excellent catalytic properties and great promise for real-world applications in HG and hydrogen storage. Characterization using X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller (BET) adsorption analysis showed Co–Zn–B nanoparticles attached to the GP surface. The catalytic activity was further improved by treating the nanocomposite with NaOH to remove zinc from the composite matrix and increase the active surface area. The BET measurements showed the specific area of the treated material increasing from 86.4 to 120.2 m2/g. The effects of temperature, NaBH4 concentration, and NaOH concentration on HG were investigated. The measured HG rate was 2180 mL/(min·g) at 30 °C in a 5 wt.% NaOH + 3 wt.% NaBH4 solution, much higher than rates obtained for unsupported Co–Zn–B catalysts. The stability of the fabricated composite catalyst was also explored.

A pragmatic method for determining the composition-dependent interdiffusivities in ternary systems by means of a single diffusion couple was developed and realized via a homemade code. Its reliability was further validated in a series of Co-based diffusion couples annealed at 1373 K by comparing with the results via the traditional Matano–Kirkaldy method. In addition, various diffusion properties were predicated, and comprehensively compared with the experimental data.

The crystal structure, microstructure, hydrogen storage properties and thermal stability of the as-cast and annealed V 35 Ti 20 Cr 45 alloys prepared by arc-melting were studied in this work. It was confirmed that the as-cast alloy is a body-centered cubic (bcc) single phase, while it consists of bcc main phase and C14-typed Laves secondary phase after annealed at 973 K for 72 h. As a result of the microstructure change, the activation performance and kinetic properties of the annealed alloy are improved greatly due to the catalysis of C14-typed Laves secondary phase in the annealed alloy. The kinetic mechanism of hydrogen absorption/desorption processes in the as-cast and annealed alloys was discussed using the Johnson-Mehl-Avrami (JMA) equation. Based on the plateau pressure data from pressure-composition-temperature (PCT) measurements with the Van't Hoff equation, the calculated formation enthalpies of the hydride formed in the as-cast and annealed alloys indicate that heat treatment results in lower thermal stability of the hydride in the as-cast alloy. Furthermore, using the Kissinger method with the peak temperatures from differential scanning calorimeter (DSC) measurements at different heating rates, the calculated activation energies of the dehydrogenation in the as-cast and annealed alloys suggest that heat treatment is very beneficial to improve hydrogen absorption/desorption capacities in the alloy.

The Sc–Ni binary system was investigated via a hybrid of experiment and thermodynamic calculation. Eleven alloys were prepared by arc melting. The as-cast and annealed samples were analyzed by means of X–ray diffraction, scanning electron microscopy with energy-dispersive X–ray spectrometer, electron probe microanalysis and differential thermal analysis/differential scanning calorimetry. The invariant reactions on Sc-rich side were reinvestigated. Five compounds (ScNi 5 , Sc 2 Ni 7 , ScNi 2 , ScNi and Sc 2 Ni) were observed in the present experiment. Their enthalpies of formation at 0 K were computed via first-principles calculations to supply referable thermodynamic data for the modeling. One single function was used to describe the Gibbs energies of both the ordered Bcc_B2 (ScNi) and disordered Bcc_A2 phases. The presently obtained thermodynamic parameters for the Sc–Ni system can reproduce the experimental data reasonably.

A thermodynamic assessment of the ternary Cr–Ni–Ti system together with a refinement for the thermodynamic description of the binary Ni–Ti sub-system is performed following the CALPHAD method and using the compound energy formalism (CEF). The ordered/disordered transition between disordered Bcc_A2 and ordered Bcc_B2 phases is described using a four-sublattice (4SL) model. An optimal set of thermodynamic parameters for the Cr–Ni–Ti system is obtained by considering the experimental data from the literature. Comparisons between the calculated and measured phase diagrams indicate that almost all of the reliable experimental information is satisfactorily accounted for by the present modeling. The complete liquidus projection and reaction scheme of the Cr–Ni–Ti system are also presented.

An effective approach to establish the atomic mobility parameters of quaternary Cu-rich fcc Cu–Mn–Ni–Zn alloys is presented through assessments of the critically-reviewed experimental diffusivities available in the literature by means of DICTRA (DIffusion Controlled TRAnsformation) software. In the quaternary Cu-rich fcc Cu–Mn–Ni–Zn alloys, atomic mobilities in ternary fcc Cu–Mn–Ni and Cu–Ni–Zn boundary systems were directly taken from our previous work, while atomic mobilities in ternary fcc Cu–Mn–Zn boudnary system were assessed as a function of temperature and composition in this work. Since no experimental data were available, the atomic mobility database for fcc Ni–Mn–Zn alloys was not assessed but just directly extrapolated based on the three constituent binary alloys. Considering that the accurate quaternary interdiffusion coefficients were usually absent in the literature, atomic mobilities in fcc Cu–Mn–Ni–Zn alloys were extrapolated based on the assessed atomic mobilities in the 4 ternary boundary systems. On the basis of the obtained mobility parameters, simulations of a series of ternary and quaternary diffusion couple experiments were performed. The concentration profiles and the diffusion paths in diffusion couples were well reproduced by the presently obtained parameters. Furthermore, 3D views of the concentration profiles, diffusion fluxes, chemical potential and quaternary interdiffusion coefficients surfaces were calculated with the obtained atomic mobilities to analyze the uphill diffusion and zero-flux plane phenomenon in some quaternary diffusion couples. In addition, simple criteria for judging whether the uphill diffusion and/or zero-flux plane can occur are also proposed.

The compositional dependence of the glass forming ability (GFA) and the correlation between their GFA and the GFA-related parameters of the Ce–Al–Co(Cu) alloys were investigated. Rapidly quenched ribbons with compositions of Ce 65 Al x Co 35 − x (x = 5, 7, 10, 12, 15, 20, 25, 27), Ce 70 Al x Co 30 − x (x = 2, 5, 7, 10, 12, 15, 17) alloys, Ce 70 Al x Cu 30 − x (x = 5, 7, 10, 13, 17) and Ce 90 − x Al 10 Cu x (x = 15, 20, 25, 30) alloys, were prepared by melting spinning, respectively, and their phase transformations were studied by X-ray diffraction (XRD) and differential scanning calorimeter (DSC) measurements. The experimental results indicated that the GFA of alloys Ce 65 Al x Co 35 − x (x = 5, 7, 10, 12, 15, 20, 25, 27) increased with the increasing Al content from 5 at.% to 27 at.%. The GFA of Ce 70 Al x Co 30 − x (x = 2, 5, 7, 10, 12, 15, 17) alloy ribbons decreased with the increasing Al content from 2 at.% to 17 at.%. Fully amorphous phase has been formed in all investigated Ce–Al–Cu alloys. It was found that only the parameter F 1 among the criteria (Δ T x , T rg , γ, γ m , γ c , δ, β, β', β m , ϕ, ξ, ω, ω', ω 2 and F 1 ) for BMGs formation could reflect the GFA of the Ce–Al–Co and Ce–Al–Cu alloys. The thermal stability of the alloys with partial amorphous is higher than that of the alloys with fully amorphous in Ce–Al–Co(Cu) alloys.

The pyrochlore-type (Sr0.6Bi0.305)2Bi2O7 containing Bi3+ and Bi5+ mixed valent states was first investigated as a new photocatalytic material in this work and successfully synthesized by a facile hydrothermal method. The phase structure, morphology, microstructure, elemental composition, and optical properties of samples were characterized in details. The experimental measurements combining with the first-principles calculations show that (Sr0.6Bi0.305)2Bi2O7 is a n-type semiconductor with a band gap of 1.25 eV. The photocatalytic activity of (Sr0.6Bi0.305)2Bi2O7 was evaluated by the degradation of various organic dyes. Our results show that (Sr0.6Bi0.305)2Bi2O7 exhibits high photocatalytic efficiency and stability under visible light irradiation. The calculated electronic density of states indicates that Bi and O atoms close to the Sr vacancy probably possess higher activity and are helpful for its photocatalytic performance.

By employing nine groups of bulk diffusion couples together with electron probe microanalysis technique, the composition dependence of ternary interdiffusion coefficients in Ni-rich fcc Ni−Al−Mn alloys at 1373 K was determined via the Matano–Kirkaldy method. The experimental interdiffusion coefficients were critically assessed to obtain the atomic mobilities of Ni, Al and Mn in fcc Ni−Al−Mn alloys by using the DICTRA (DIffusion-Controlled TRAnsformations) software package. The reliability of these mobilities was validated by comprehensive comparison between the model-predicted diffusion properties and the experimental data. The obtained atomic mobilities could be used to describe various diffusion phenomena in fcc Ni–Al–Mn alloys, such as the concentration profiles, interdiffusion flux and diffusion paths.

The kinetics of the glass transition of Ce 65 Al 20 Co 15 metallic glass has been investigated using differential scanning calorimetry (DSC) technique with continuous heating of the sample at different heating rates. The dependence of the glass transition temperature ( T g ) on the heating rate ( β ) has been determined. The activation energy ( E ) of the glass transition has been obtained by employing Moynihan and Kissinger methods, respectively. It is found that the glass transition process cannot be described in terms of single activation energy. The variation of E with the extent of conversion ( α ) is further analyzed by using two iso-conversional methods. It is observed that the E of glass transition varies throughout the glass transition region. It is indicated that the transformation from amorphous to a supercooled liquid phase of Ce 65 Al 20 Co 15 metallic glass is a complex process.

The Bi-M (M = Ti, Cr, V) systems have been critically reviewed and modeled by means of the CALPHAD technique. All the intermetallics (BiTi3, BiTi2, Bi9Ti8, Bi3Ti2 and Bi2Ti) were treated as stoichiometric compounds. The enthalpy of formation at 0 K for BiTi2 was computed via first-principles calculations to assist the thermodynamic modeling. The gas phases for the Bi-Cr and Bi-V systems were treated as ideal gas. A set of self-consistent thermodynamic parameters has been finally obtained for each of these binary systems. Comparisons between the calculated and measured phase diagrams as well as first-principles calculations show that most of experimental data can be satisfactorily reproduced by the present thermodynamic descriptions.

In this study, polypyrrole (PPy) nanofibers were used to synthesize a super-activated carbon material. A highly-dispersed Co-Ni-B catalyst was supported on PPy nanofiber-derived activated carbon (PAC) by chemical reduction. The Co-Ni-B/PAC hybrid catalyst exhibited excellent catalytic performance for the decomposition of ammonia borane (AB) in an aqueous alkaline solution at room temperature. The size of the metal particles, morphology of Co-Ni-B/PAC, and catalytic activity of the supported catalyst were investigated. Ni-B, Co-B, and Co-Ni-B catalysts were also synthesized in the absence of PAC under similar conditions for comparison. The maximum hydrogen generation rate (1451.2 mL−1·min−1·g−1 at 25 °C) was obtained with Co-Ni-B/PAC. Kinetic studies indicated that the hydrolysis reaction of AB was first order with respect to Co-Ni-B/PAC, and the activation energy was 30.2 kJ·mol−1. Even after ten recycling experiments, the catalyst showed good stability owing to the synergistic effect of Co-Ni-B and PAC.

The binary Ce–Cu system has been re-investigated via the selected eighteen key alloys by means of the differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with energy dispersive X-ray analysis techniques. Five intermetallic compounds, Cu 6 Ce, Cu 5 Ce, Cu 4 Ce, Cu 2 Ce, and CuCe, have been confirmed. Cu 6 Ce and Cu 2 Ce melt congruently at 947 °C and 810 °C, respectively. Cu 5 Ce, Cu 4 Ce, and CuCe are formed through peritectic reactions, L + Cu 6 Ce ↔ Cu 5 Ce at 799 °C, L + Cu 5 Ce ↔ Cu 4 Ce at 792 °C, and L + Cu 2 Ce ↔ CuCe at 492 °C, respectively. Three eutectic reactions, L ↔ (Cu) + Cu 6 Ce at 879 °C, L ↔ Cu 4 Ce + Cu 2 Ce at 753 °C, and L ↔ CuCe + (γCe) at 407 °C, have been observed. One catatectic reaction, (δCe) ↔ L + (γCe) at 702 °C, was determined. According to the present experimental results, the Ce–Cu phase diagram is revised.

The isothermal section of the Ce-Co-Al ternary system at 573 K was investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques. It consisted of 19 single-phase regions, 46 two-phase regions and 25 three-phase regions. Four ternary compounds, namely CeCoAl, Ce2Co15Al2, CeCoAl4, CeCo2Al8, were confirmed in this system. At 573 K, the maximum solid solubilities of Co in CeAl2 and Al in CeCo2 were about 10.4 at.% and 10.0 at.%, respectively. The homogeneity range of CoAl phase extended from about 46.0 to 56.0 at.% Al.

The isothermal section of the Fe–Ni–Ta system at 1100 °C was constructed using 6 diffusion couples and 10 alloys, the compositions of which were selected on the basis of the experimental results of the (Fe–Ni alloy)/Ta diffusion couples. The samples were examined by means of optical microscopy, scanning electron microscopy, and electron probe microanalysis. Experimental results showed no existence of ternary compounds at 1100 °C. The following five three-phase equilibria were observed: (1) (Ta) + Ta 2 Ni + Ta(Fe, Ni), (2) Fe 2 Ta + Ta (Fe, Ni) + TaNi 2 , (3) Fe 2 Ta + TaNi 2 + TaNi 3 , (4) Fe 2 Ta + TaNi 3 + (Fe, Ni), (5) TaNi 3 + TaNi 8 + (Fe, Ni). The compounds FeTa and NiTa formed continuous solid solution. The solubility of Fe in TaNi 2 and TaNi 3 was determined to be 18 and 7.8 at.%, respectively, while the solubility of Ni in Fe 2 Ta was estimated to be 40 at.%.

The Al–rich corner of ternary Al–Ce–Ni metallic glass forming system was investigated by a hybrid approach of thermodynamic modeling and first–principles calculations. A consistent thermodynamic data set for the Al–Ce–Ni system was obtained. Based on the correlation between glass forming ability and thermodynamics, we found that there are no deep eutectics in the Al–rich corner. Alloys with high GFA appear in off–eutectic area with heat of mixing ranging from −15 to −49 kJ/mol of atom, and the alloy with a local minimum driving forces show highest GFA according to the melt spinning and copper mold casting experiments and the calculation of driving force for the formation of crystalline phases in the supercooled liquid state. The nucleation driving force is the dominant factor determining the formation of amorphous phases, among several other factors such as heat of mixing, viscosity, and glass transition temperature.

The wettability of MnxSiyOz by liquid Zn-Al alloys was investigated to obtain basic information on the coating properties of high-strength steels with surface oxides in the hot-dip galvanizing process. In this study, the contact angles of liquid Zn-Al alloys (Al concentrations were 0.12 and 0.23 wt pct) on four different MnxSiyOz oxides, namely MnO, MnSiO3, Mn2SiO4, and SiO2, were measured with the dispensed drop method. The contact angle did not change across time. With an increasing Al concentration, the contact angle was slightly decreased for MnO and Mn2SiO4, but there was no change for MnSiO3 and SiO2. With an increasing SiO2 content, the contact angle gradually increased by 54 wt pct to form MnSiO3, and for pure SiO2 substrate, the contact angle decreased again. Consequently, the MnSiO3 substrate showed the worst wettability among the four tested oxide substrates.

We propose an efficient partial transmit sequence technique based on genetic algorithm and peak-value optimization algorithm (GAPOA) to reduce high peak-to-average power ratio (PAPR) in visible light communication systems based on orthogonal frequency division multiplexing (VLC-OFDM). By analysis of hill-climbing algorithm’s pros and cons, we propose the POA with excellent local search ability to further process the signals whose PAPR is still over the threshold after processed by genetic algorithm (GA). To verify the effectiveness of the proposed technique and algorithm, we evaluate the PAPR performance and the bit error rate (BER) performance and compare them with partial transmit sequence (PTS) technique based on GA (GA-PTS), PTS technique based on genetic and hill-climbing algorithm (GH-PTS), and PTS based on shuffled frog leaping algorithm and hill-climbing algorithm (SFLAHC-PTS). The results show that our technique and algorithm have not only better PAPR performance but also lower computational complexity and BER than GA-PTS, GH-PTS, and SFLAHC-PTS technique.

The phase relations of the ternary system Ce-Al-Cu in the Cu-poor part at 503 K were investigated by X-ray powder diffraction (XRD). The investigated composition region consists of 16 single-phase, 32 two-phase and 17 three-phase regions. At 503 K, the maximum solid solubilities of Cu in Al, alpha-Ce(3)Al(11), CeAl(3) and CeAl(2) are about 2.5 at.%, 1.6, 3.6 and 5.3, respectively, and Al in CeCu(5) is about 39.2 at.% The homogeneity ranges of Al(2)Cu and AlCu phases extend from about 32.1 to 32.6 at.% Cu and 49.7 to 52.4 at.% Cu, respectively. Five ternary compounds and their solid solutions have been observed in this work: CeAl(12-x)Cu(x) (4.0

The phase equilibria at 500 °C in the Al–Ce–Ni system in the composition region of 0–33.3 at.% Ce are investigated using XRD and SEM/EDX techniques applied to equilibrated alloys. The previously reported ternary phases and the variation of the lattice parameters versus the composition for different solid solution phases are investigated. It is confirmed that τ 2 (Al 2 CeNi) exists at 500 °C, while τ 3 (Al 5 Ce 2 Ni 5 ) does not exist at 500 °C. A new compound τ 9 with composition of about Al 35 Ce 16.5 Ni 48.5 is found. The solubility of Ni in Al 11 Ce 3 and αAl 3 Ce is generally about 1 at.%, while the solubility of Ni in Al 2 Ce is measured to be 2.7 at.%. The solubility of Ce in Al 3 Ni, Al 3 Ni 2 , AlNi and AlNi 3 is all less than 1 at.%. The solubility of Al in CeNi 5 , Ce 2 Ni 7 and CeNi 3 is measured to be 30.4, 4.8 and 9.2 at.%, respectively, while there is no detectable solubility for Al in CeNi 2 . A revised isothermal section at 500 °C in the Al–Ce–Ni system has been presented.

Based on the critically reviewed experimental data available in the literature, new phase transition temperatures and phase equilibria at 800 °C close to the Cu-Fe side of the Cu-Fe-Mn system were measured in the present work. The composition-invariant (γFe, γMn) → (αFe) massive transformations were observed in the two quenched alloys in the Fe-rich region. A set of consistent thermodynamic parameters of the Cu-Fe-Mn system was then obtained by taking into account all kinds of experimental data. Comparisons between the calculated and measured phase diagrams indicate that most of the experimental information is satisfactorily described by the present thermodynamic modeling. The liquidus isolines, liquidus projection and reaction scheme of this ternary system are also presented. Significant improvements have been made, compared with the previous assessments. The presently obtained parameters were applied in successfully solving the !surface fissure" during hot rolling of steel and controlling the micro-structure of the Cu-Fe based alloys in rapid solidification.

In order to ascertain the reaction type for the degenerated equilibrium among liquid, (Al) and NbAl 3 , differential scanning calorimetry (DSC) measurements with heating and cooling rates of 2, 5 and 10 K/min are performed for the annealed pure Al and Al 0.97 Nb 0.03 (atomic fraction) samples. The degenerated equilibrium is identified to be a peritectic one by extrapolating the heating rates to 0 K/min. A set of self-consistent thermodynamic parameters for the Al–Nb system is then obtained by means of the calculation of phase diagram (CALPHAD) approach applied to the experimental phase diagram and thermodynamic data from the literature and the present work. The calculated phase diagram and thermodynamic properties agree well with the corresponding experimental ones. The unusual feature associated with the previous modeling ( i.e ., the appearance of ordered Bcc_B2 phase at low temperatures) is avoided in the present modeling.

The phase equilibria at 850 °C and 627 °C in the Al–Fe–Ni system with Al content above 50 at.% are investigated by using 19 alloys. The annealed alloys are examined by means of X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and electron probe microanalysis (EPMA). It is confirmed that τ2 phase (Al10Fe3Ni) with hexagonal structure and τ3 phase (Al71Fe5Ni24) with the decagonal quasi-crystalline structure, exist at 850 °C. The homogeneity of τ2 spans in the range of 5.7–13.1 at.% Ni and 14.4–22.2 at.% Fe. At 850 °C, the maximum solubilities of Ni in Al5Fe2 and Al2Fe are determined to be 1.3 at.% and 2.1 at.%, respectively, while the maximum solubility of Fe in Al3Ni2 is measured to be 4.9 at.%. At 627 °C, τ1 (Al9FeNi) and τ2 exist. At this temperature, the homogeneity range for τ1 is from 8.7 at.% to 14.3 at.% Ni and 4.5 at.% to 10.0 at.% Fe, and that for τ2 is within the range of 7.2–12.4 at.% Ni and 15.6–22.5 at.% Fe. The maximum solubilities of Ni in Al13Fe4, Al5Fe2 and Al2Fe are determined to be 8.9, 1.5, and 2 at.%, respectively, while that of Fe in Al3Ni is measured to be 3.6 at.%. At 627 °C, the maximum solubilities of both Fe and Ni in (Al) phase are determined to be extremely small, about 0.58 at.% for both elements.