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The solubility limit of elements plays a crucial role in alloy designing, as well as in the understanding of kinetic processes in alloys. Using first-principles calculations, we calculated the ground states of Fe-RE compound, and predicted the stable and metastable structures of Fe-Y and Fe-Ce. The results indicate that the stable structures for Fe-Y compounds are Fe12Y.tI26, Fe17Y2.hP38 and Fe2Y.cF24, and those for Fe-Ce binary are Fe17Ce2.hP38, Fe19Ce5.hR24 and Fe2Ce.cF24. Based on the statistical-thermodynamic theory of dilute lattice gas, we presented a systematic series of calculations of the solubility limits of RE in α-Fe as a function of temperature. It is found that the solubilities are sorted in the following order: SLa>SCe>SY, corresponding to the trend in the solubility formation enthalpies: Hsol(La)

A novel organic/inorganic hybrid which consisted of N,N-diphenyl-4-(2,2':6′,2″-tepyridin-4-yl)aniline (abbreviated as TPPA) and CdS nanoparticles (NPs) had been prepared through interfacial coordination effect according to soft-hard-acid-base principle. The interfacial coupling coordination was analyzed by XRD, far-IR, FT-IR and HRTEM, which resulted in changeable morphology and tunable linear/nonlinear optical properties. Upon interfacial coordination, the hybrid showed a red-shifted (55 nm) UV–vis absorption band, weakened single photon fluorescence emission (84% decrease), and enhanced two-photon absorption cross-section (13 folds). Due to excellent two-photon absorbing character, the hybrid had good application in the field of optical power limiting with 43 W⋅cm−2 limiting threshold. The regulation mechanism of optical properties was thoroughly discussed upon single crystal structure of the interfacial coordination complex and quantum calculation, as well as the growing mechanism of the hybrid.

The effects of antimony (Sb) on the deformation behaviour of high-grade non-oriented silicon steel at a low temperature were studied by using a Gleeble-3800 thermal simulator and the field-emission scanning-electron microscope. The tensile strength of the high-grade non-oriented silicon steel without Sb was significantly lower than that of the high-grade non-oriented silicon steel with Sb within the tensile temperature range of 25 °C–240 °C. It is possible for Sb atoms near the grain boundary to diffuse at hundreds of atoms through dislocations as a rapid diffusion channel, which is driven by thermal activation with an increase in temperature. Atomic diffusion can weaken the damage to bonding forces on the grain boundary and crack propagation along the grain boundary under load action. The segregation of Sb atoms at the grain boundary decreased gradually, which weakened the cleavage characteristics of the fracture morphology and enhanced its dimple characteristics. For a stretching temperature of 80 °C, the fracture dimple of high-grade non-oriented silicon steel without Sb was significantly more than the high-grade non-oriented silicon steel with Sb. Because of the weakening effect of Sb segregation at the grain boundary, the suitable low-temperature deformation range for high-grade non-oriented silicon steel with Sb was 120 °C–160 °C.

The effect of Mn on the corrosion resistant property of heat-treated AZ91 alloys was investigated by electrochemical, static mass loss tests and salt spray corrosion method. The micromorphologies of the corroded samples of the alloys were studied by scanning electron microscope (SEM), and the phase composition and the corrosion products of the alloys were analyzed by X-ray diffractometer (XRD). Results demonstrate that an independent phase Al 6 Mn is formed in AZ91 alloy. The solubility of the phase in solid solution of Mg can increase the electrode potential of Mg. Mn addition can increase the corrosion potential, decrease the corrosion current density of AZ91 alloys and reduce corrosion rates. Therefore, the corrosion resistance of alloys is improved. AZ91-0.8Mn alloy shows the best corrosion resistance capacity among all of the specimens among all of the specimens.

The carbon fiber–reinforced plastics have gained considerable attention in the aerospace industry in recent years. Drilling of carbon fiber–reinforced plastic is relatively difficult with too much fiber delamination and pulling out in the entry and exit of the holes. As an advanced hole-making technology, helical milling is being developed in machining of carbon fiber–reinforced plastic, in which the tool moves on a helical course to the workpiece. Experiments were carried out on helical milling of carbon fiber–reinforced plastic, the effects of the cutting parameters and tool wear on the cutting forces are analyzed, and the relation between hole quality and cutting forces is also discussed. In order to simulate the cutting forces under different cutting conditions, the mechanistic modeling technique is used to predict cutting forces in helical milling of carbon fiber–reinforced plastic, and the cutting force coefficients are identified and corrected based on the experimental data. The results show that the established model can be used to predict the cutting forces in the helical milling process.

The structural and thermodynamic properties of TiAl intermetallics under high pressure have been investigated by ab initio plane-wave pseudopotential density functional theory method. It is found that the ratio of lattice parameter c to a keeps almost constant with a value of 1.02 under the pressure from 0 to 20 GPa, which agrees well with the experimental results. With the pressure increasing from 20 to 45 GPa the values of c/a decrease almost linearly from 1.02 to 0.99. These calculated results indicate under low pressure the variation rate for a-axis is almost the same to that for c-axis, but under higher pressure the variation for a-axis is smaller than along c-axis. Through the quasi-harmonic Debye model, the equation of state (EOS) of TiAl intermetallics, as well as the thermal expansion and heat capacity at various pressures and temperatures are also studied.

As one of the main disasters in mine explosion, gas explosion is a chain chemical fast-reaction. Combustion chain reaction is inhibited by gas explosion suppression technique, which controls the explosive development and reduces the damage of explosion artificially. Based on the experimental research, the study compared and analysed the type K and S condensed aerosol's impact on the explosive limits of methane concentration and the critical oxygen concentration of methane explosion. The results show that with the increase of aerosol concentration, the methane explosion limits is decreased. Different concentrations or types of aerosol have different effects on methane explosion. When the concentration of S aerosol is 315 mg/L, the methane won’t explode. On the same of aerosol concentration, S aerosol has a better explosion suppression effect than K.

The objective of this paper is to study the filling process of titanium alloy melt in vertical centrifugal casting, as well as the effect of processing parameters on the formation of defects of titanium alloy castings. Experimental results show that the castings obtained in the centrifugal field are better than that obtained in the gravity field. The molten metal sticks to one side of the mould which is opposite to the rotational direction to fill in the vertical centrifugal field. And the cross-sectional area of the molten metal in the runner decreases with increasing of filling length, but has a back-up trend at the inlet of ingate due to the decreases of filling velocity at the ingate. The processing parameters such as rotational direction, rotational radius and rotational velocity play an important role in the formation of defects of titanium alloy castings. Different rotational direction leads to different filling sequence of molten metal, which then affect the following solidification and the formation of the defects. Under the given rotational velocity, the volume of inner defects of castings decreases with increasing of rotational radius and rotational velocity.

A method both convenience for generation and calculation for anticipated ASE waveform in spun fiber Raman amplifier,by analyzing the NLSE of signal and pump wave in fiber,is proposed.According to its time domain characters,a non-Gaussian noise ASE model is established and the term is added to the NLSE simultaneously by considering birefringence rotation effect in spun fiber Raman amplifier.By solving the equation with Split Step Fourier Method,ASE in spun fiber Raman amplifier is investigated.Numerical results for the ASE noise power spectrum are validated.

The study of reducing olefins properties on nano-HZSM-5 catalyst was investigated with a continuous fixed reactor using fraction of fluid catalytic cracking gasoline (75N120°C). The experimental results showed that nano-HZSM-5 catalyst has the best reducing olefins properties under the optimal conditions: temperature 430°C, pressure 0.3 MPa, and liquid hourly space velocity 1 h−1, and the content of olefins in the feed stock decreased to 12.11% and dropped 31 percentage points. The yield of liquid product, the content of aromatics, and the content of isoalkane in liquid product are up to 84.98%, 39.58%, and 35.23% respectively.

Microstructure evolution of Fe-1.18%Cu binary alloy during solution and aging at 550°C was investigated under a high-resolution electron microscopy (HREM). In addition, the aging strengthening mechanism was investigated based on the precipitation strengthening theory. Results show that there were lots of Cu atom clusters in the ferrite matrix during solid solution and initial aging stage, and Cu-rich metastable Fe-Cu particles precipitate subsequently at the aging hardness peak. It is found that there were high-density dislocations and stacking fault substructure in the Cu clusters that forms the obstacle of the dislocation motion, which should be the dominant reason of strengthening in the Fe-Cu alloy.

A catalyst is provided for the selective hydrogenation of dienes from fluid catalytic cracking gasoline. There are a small quantity of dienes in fluid catalytic cracking gasoline which can deteriorate the quality of fluid catalytic cracking gasoline, as well as make its further process inconvenient. These dienes must be reduced as impurity. In this paper, the nickel supported on alumina selective hydrogenation catalysts modified with magnesium promoter are prepared by impregnation method. The fluid catalytic cracking gasoline (

The intermolecular interaction potential for methane–argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane–argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R) = 143794365.332/R12−3032.093/R6 (R in a.u. and V(R) in eV).

In this paper, the effects of rare earths (RE) added in bath on the chemical composition, the microstructure, the polarization curves and the corrosion rate of Ni–P coatings have been investigated by energy dispersion spectra (EDS), auger electron spectra (AES), X-ray diffraction (XRD), transmission electron microscopy (TEM), potentiodynamic scan and immersion test. The results of immersion tests show that the corrosion resistance of the Ni–P coatings is greatly improved by the addition of RE, which is attributed to the formation of an amorphous phase in the coatings. This formation of the amorphous phase is from the effect of RE ions on the coelectrodeposition process of Ni and P. RE ions make the cathodic polarization to increase obviously. But RE ions themselves do not codeposite with Ni and P. And they have no effect on the P content of the coatings. According to the results of potentiodynamic scans, EDS, AES and the data of the corresponding standard electrode potential it can be deduced that RE ions can change the structure of the double-layers of cathodic and disturb the depositing behavior of Ni ions, thus promote the formation of amorphous phase.

Composite absorbent (CAds-AC-15) mainly used activated carbon and CaCl2 as the resources for adsorption refrigeration were prepared by the mixed method, and the content of activated carbon in CAds-AC-15 was 15%. Adsorption isotherms of ammonia on CAds-AC-15 were determined by positive gravimetric method. Adsorption - desorption cycle performance and cooling characteristics of CAds-AC-15-ammonia working pair was evaluated by self-made adsorption - desorption measuring device. Experimental results show that the equilibrium capacity of ammonia on the CAds-AC-15 is up to 1.136kg/kgads at 30?, which is 5% lower than that of CaCl2. With the conditions of adsorption temperature 30?, ammonia evaporation pressure 0.25 MPa, desorption temperature 300?, the performance of CAds-AC-15- ammonia working pair is stable after repetitious adsorption-desorption cycles, adsorption capacity of ammonia on the CAds-AC-15 and its cyclic adsorption capacity is 0.55~0.65 kg/kg and 0.2~0.25 kg/kg, respectively. The cooling capacity is up to 328.38kJ/kgads, which is twice as high as CaCl2 - ammonia working pair.

The effect of annealing process on the microstructure of Fe-0.3%Si electrical steel was investigated in this work, and the steel the microscopic orientation of experimental steel was examinated by electron back scatter diffraction (EBSD) technique as well .The result indicated the start time of recrystallization from 700 for 10 s ahead of time to 760 for 4s; with the annealing temperature increased, recrystallization rate enhances to 740 10 s 22.5% from 700 10 s 5% along, and the average crystal grain size increases to 740 10 s 3.08 μm from 700 10 s 1.97 μm; while along with soaking time increasing, recrystallization rate enhances to 740 360 s 100% from 740 10 s 22.5%, average crystal grain size increases to 740 360 s 17.17 μm form 740 10 s 3.08 μm; It was observed that the recrystallization mainly formed from the grain boundary of the deformation matrix with relatively high aberrations energy in 740 6 s the partial recrystallization microstructure, which confirmed the directional nucleation theory. The electro technical steel also is called the silicon steel, which is one kind of ferrosilicon soft magnetism alloy low carbon amount. It is the electric power and the telecommunication industrial used to making the generator, the electric motor, the transformer, the mutual inductor, the relay as well as other electric appliance measuring appliance important magnetic material, the cold rolling silicon steel plate is one kind of outstanding soft magnetism functional materials. At present, the non-orientation silicon steel is the biggest, the use broadest cold rolling silicon steel material.In "by Leng Daire" under the major tendency, the research of cold rolling non-orientation silicon steel has vital significance. The influence of the annealing process on the silicon steel microstructure was studied in this experiment, to provide reference for the actual factory production. (3 pages)

The phase transformation activation energy of the Cu61.13Zn33.94Al 4.93 alloys, which were treated at 4 GPa and 700 °C for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94Al4.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β' → β and β → β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5–20 °C/min.

Effects of high pressure (6 GPa) on the solid state phase transformation kinetic parameters of aluminum bronze during the cooling process are investigated, based on the measurement and calculation of its solid state phase transformation temperature, duration and activation energy and the observation of its microstructures. The results show that high pressure treatment can reduce the solid phase transformation temperature and activation energy in the cooling process and can shorten the phase transformation duration, which is favorable when forming fine-grained aluminum bronze.

The characteristic of microscopic plasticity associated with collapse of helium bubble and void in single-crystal aluminum under the same shock loading strength has been investigated by molecular dynamics (MD) simulations. The results show that both the helium bubble and the void collapse through the emission of shear dislocation loops, while prismatic dislocation loops are never observed in the simulations. The preferential dislocation nucleation sites are similar for the helium bubbles and the voids, but the number of dislocations emitted from the helium bubble outnumbers that from the voids, and the dislocation loops emitted from the helium bubbles move faster than that from the voids. Meanwhile, it is more difficult to emit dislocation loops from the leading side (the side which the shock hits first) of both the helium bubbles and the voids than from the trailing side. By analysing the resolved shear stress along the slip plane, we found that the internal pressure of the helium bubbles increase the resolved shear stress and make the dislocation emission from the helium bubbles much easier than from the voids. The curvature change from the leading side to the trailing side produced by the shock modifies the critical shear stress for dislocation nucleation, which explains the difference in the plasticity between the leading side and the tailing side of both the helium bubbles and the voids. The result will contribute to a better understanding of the microscopic mechanism through which irradiation damages affect the dynamic properties of metals.

The elastic properties of helium-bubble embedded aluminum have been investigated by molecular dynamics simulation. First, the interaction potentials between aluminum and helium atoms are parametrized with the help of first-principle method. Secondly, we studied the influence of helium bubble on the elastic properties of aluminum from the following two aspects: the size of helium bubble (the diameters being 16, 20, 25, 30 and 3.5nm, respectively) and the internal pressure of helium bubble (the ratios of the number of helium atoms to the vacancies being about 5%, 15%, 45% and 85%, respectively). The results show that the elastic constants c11, c12 and c44 decrease with increasing diameter of helium bubble, however, for a fixed size they are almost independent of the internal pressure of helium bubble. Using the elastic composite system model, the influence of the size and internal pressure of helium bubble on aluminum is explained qualitatively based on the analytical results and is consistent with our calculated results.

The poled PZT 95/5 ferroelectric ceramic is in ferroelectric (FE) phase, it can be transformed into the antiferroelectric (AFE) phase by shock compression, so the bound charge can be liberated into an external circuit to generate pulses of electrical current. Based on this FE/AFE transition theory, the electrical response of LRC load was discussed, especially for the small resistance (R) and small inductance (L) load in this paper. A set of PZT 95/5 ceramics in parallel connection was devised to generate large pulses of electrical current in two plane-wave tests. The maximum output current reaches above 5 kA, and the corresponding rise time of the front edge is under 500ns.

The preparation of silicon nanoporous pillar array (Si-NPA) and Fe3O 4 coated Si-NPA (Fe3O4/Si-NPA) is presented. The morphologies and microstructures of the two kinds of thin films were characterized and their corresponding capacit ive humidity sensing properties investigated. It was shown that both Si-NPA and Fe3O4/Si-NPA are typical micron/nanometer structural compo site systems. When the relative humidity increased from 11% to 95%, the capacitances reached 1500% and 5500% of their initial values measured with 100 Hz signal frequency, and 800% and 12000% measured with 1000 Hz signal frequency, for Si-NPA and Fe3O4/S i-NPA, respectively. At the same time, both of the two thin films exhibited quic k response speed, the response times in the humidity-increment and humidity-decr ement processes were determined to be 15 s and 5 s for Si-NPA, and 20 s and 15 s for Fe3O4/Si-NPA, respectively. These excellent humidity sensing properties of Si-NPA and Fe3O4/Si-NPA are explained based on thei r corresponding morph ological and structural properties. Our experiments strongly indicated that Si-N PA is an ideal thin film both for direct humidity sensing and as a substrate for growing composite humidity sensing materials.

Influence of pressure on solidification microstructure of FeSi2 alloy is investigated. Different from the eutectic structure of the sample solidified at normal pressure, the microstructure of the sample solidified at high pressure is composed of dendritic primary phase and anomalous eutectic. The significant change in microstructure results from the change of phase diagram and solute atom diffusion induced by high pressure. By introducing the pressure parameter, the constitution undercooling criterion is attained. Formation mechanism of dendritic primary phase under high pressure is analysed according to the constitution criterion.

The characteristics of terahertz (THz) radiations from the surfaces of two kinds of narrow-band semiconductors InN and InAs excited by femtosecond laser pulses with different pump powers (from 10 to 320mW) are investigated experimentally. The results show that InAs can irradiate a stronger THz signal than that of InN under the same pump power so its radiation efficiency is higher. However, the spectral widths of THz radiations from these semiconductor surfaces increase with the increase of pump power. When the intensity of pump laser is high enough, the spectral Half-Maximum-Full-Width (HMFW) of THz radiation tends to be a constant. Compared with InAs, InN can reach this constant HMFW THz spectrum at a lower pump power. This research is significant for investigating the THz radiation mechanism from semiconductor surfaces, and it is also a good reference for exploring a THz radiation source with low cost and high efficiency.