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A novel Cu(II) compound [CuL2]·2H2O was synthesized by hydrothermal methods, and its crystal structure was determined by single-crystal X-ray diffraction. The title compound crystallized in the monoclinic space group P21/c as an isolated monocyte structure. The strong π…π stacking and hydrogen bonding interactions produce one-dimensional (1D) chains. A series of properties of the title compound were tested by solid state photoluminescence, CIE analysis and solid-state diffuse reflectance. The results show that the compound is a blue light emitter, CIE (0.1291, 0.0783) and has an energy bandwidth of 1.65 eV. Time-dependent density functional theory (TDDFT) calculation results show that the emission of the compound can be attributed to charge transfer from metal to ligand and ligand to ligand (MLCT and LLCT). A novel Cu (II) complex is synthesized via hydrothermal preparation, which is characteristic of an isolated structure, at the same time, it displays a narrow and intense photoluminescence emission band in the blue region and theoretical study reveals that the photoluminescence emission is originated from the metal-to-ligand and ligand-to-ligand charge transfer transition.

A novel cadmium compound [CdL(bipy)2]·6H2O was synthesized by hydrothermal method, and its crystal structure was determined by single-crystal X-ray diffraction. The title compound crystallized in t...

This study investigated the hydration mechanism of gypsum–slag cement gel. Experimental results indicated that products of hydration of gypsum slag cement gel materials were predominantly z...

The influences of Ar[Formula: see text] energy and low-energy sputtering on the structure of Cu–W thin film prepared by double-ion-beam sputtering are studied. Results show that the Cu–W thin film sputtered by ion beam onto a Cu substrate is in the form of an amorphous tungsten framework mechanically mixed with Cu grains when the Cu-target Ar[Formula: see text] energy is within 1–2[Formula: see text]keV and the W-target Ar[Formula: see text] energy is 3[Formula: see text]keV. The Cu grain size increases slightly, increasing the Cu-target Ar[Formula: see text] energy. When the Ar[Formula: see text] energy increases to the critical value ([Formula: see text][Formula: see text]keV), a small amount of Cu is transformed into a single crystal, forming a solid solution with the melting of W. Due to crystal defects and lattice distortion, there is a small shift in the Cu diffraction peak.

The paper analyses the manufacturability and difficulties in weld repairs of the electroslag casting red copper crucible with bent axle, work out the relevant measure. It is proved by experiment that large red copper product can be perfectly repairs by use suitable welding procedure.

The fracture behavior and microstructural effects on the toughness of a medium carbon wheel steel were systematically investigated by using instrumented impact tests. The microstructure of the steel consisted of lamellar pearlite and a small amount of proeutectoid ferrite. The results showed that with the refinement of prior austenite grain size, the pearlite block size decreased and the ferrite content increased, while the pearlite interlamellar spacing kept almost unchanged. The impact toughness was improved in the temperature range from −80 °C to room temperature. Observation of fracture surfaces revealed that the fracture occurred in a brittle manner, which was characterized by cleavage and a small proportion of ductile fracture. However, the toughness was positively correlated to the ductile fracture area. Cleavage cracks were found to be initiated at the sites of proeutectoid ferrite, pearlite colony or pearlite/ferrite interface. The values of macroscopic cleavage fracture stress measured were similar (~1833 MPa) for the specimens with different pearlite block size and ferrite content but the same pearlite interlamellar spacing. The toughness improvement by microstructural refinement in the transition temperature region was attributed to the increase in cleavage crack initiation energy. The cleavage crack propagation energy was, however, relatively low and mainly unchanged. With decreasing the test temperature, the difference in crack initiation energy was decreased, causing the difference in total impact absorbed energy to decrease. The results also suggested that in the lower shelf temperature region where complete cleavage fracture occurred, the toughness was insensitive to the microstructural parameters.

A method based on Dual-Tree Complex Wavelet Transform (DT-CWT) was proposed for enhancing the images. By taking into account the non-Gaussian probability distribution and the statistical dependencies among wavelet coefficients of some signals, and by taking advantage of near shift-invariance of DT-CWT, it can obtain higher signal-to-noise ratio (SNR) than common wavelet denoising methods. The simulation results show that the proposed method is better than the traditional methods. It has a good enhancement performance which can improve the details of the image automatically.

Hilbert-Huang Transform (HHT) Spectrum is analyzed, and is compared with Wigner-Ville distribution(WVD). And it is proposed a method that is “band pass filtering --signal purification and reconstruction --HHT spectrum analyses” method to carry on the state recognition and fault diagnosis of the mechanical equipment. The compared signals include: the signals of harmonic, amplitude modulation and frequency modulation, and the mixed signals that are composed of these single signal, then it is pointed out: HHT Spectrum have higher frequency resolution than WVD, and it has overcome the latter influence of cross-term interference. At last, real signals of fault gear are analyzed by this method, and it is indicated that the method can offer a new and effective method for fault diagnosis and condition monitoring.

Cu-4%C mixed-powder consisting of rough copper powder and graphite powder was separately mechanical alloyed by high energy ball milling. The phases and micrograph of these powders were determined by X-ray diffraction and scanning electron microscopy (SEM). The results show that increase of the lattice parameter of copper with milling times, up to a saturation value of about 24h; The absence of graphite reflections in X-ray diffract grams for longer milling times.

We preliminary know FS powder and coal dust play in mix sand and analysis comparison influence of each powder through a series of mixture sand performance testing . We put forward on same addition, FS powder substitute coal dust is profitable to reduce defect of M593 Shell structure adhering sand.

The semi-solid microstructure of ZL101 alloy was fabricated by technology of vibrating inclined cast. The effections of length of slope and vibration voltage on microstructure were also investigated. The experimental results showed that two parameters played an important role on the microstructure of ZL101 alloy. The homogeneous, small and rounded sphere-like semi-solid equiaxed crystals were obtained when the ZL101 alloy was cast in water-cooled copper mold with 25cm slope length at 640 °C and 60v vibration voltage, the average grain diameter and shape factor of which was 26.5um and 0.8, respectively.

The influences of heating temperature and holding time on the microstructures were investigated during the semi-solid remelting process of rare earth Al-4.5Cu alloy. The evolution mechanism of crystal organization was discussed. Experiments show that the heating temperature and holding time are very important to the grain size and uniformity. It is the most suitable parameters, as heating temperature is 630°C and holding time is 20 minutes, to remelting process. During the remelting process, grain mergering and Ostwald growing up is the main mechanism of change on microstructures.

In order to research the adhesion of sputtering protective coating of Gd. Gd substrates was coated with 1Cr18Ni9Ti by means of DC magnetron sputtering technology. The characteristics of the film were investigated by scanning electron microscopy (SEM), EDS, SPM and the adhesions of film was tested by tension test. The results show that the films of 1Cr18Ni9Ti are distributed by means of islands when the sputtering was initiated and the grains are like thin fiber. After a few minutes, the films are smooth and perfect, the interferences between 1Cr18Ni9Ti and Gd join together strongly, and the largest strength of adhesion is 24.7MPa when the sputtering density is 966 w/cm2 and the sputtering time is 8 minutes.

In order to research the adhesion of sputtering protective coating of Gd. Gd substrates were differently coated with 1Cr18Ni9Ti, Ti, Cu and Al by means of DC magnetron sputtering technology. The characteristics of the films were investigated by scanning electron microscopy (SEM), EDS, and the adhesions of films were tested by tension test. The results show that the films of 1Cr18Ni9Ti, Ti and Al are smooth and perfect, the interferences between 1Cr18Ni9Ti, Ti, Al and Gd join together strongly, and the average strength of adhesion is 25MPa in these tests on the optimize parameters. While the films of Cu are rough and bad, the interferences between Cu and Gd join together loosely, and the largest strength of adhesion is only 3.02MPa in these tests on the optimize parameters.

A matching pursuit method based on Dual-Tree Complex Wavelet Transform (DT-CWT) is proposed for extracting feature. Many new orthogonal wavelet bases formed Hilbert transform pairs is constructed by the method which is based on the sufficient and necessary condition on constructing wavelet, via the flat delay filter, and translated the problem into resolving algebraic equations. And taking these wavelets as choice object, a matching pursuit method based on DT-CWT is used for extracting feature. The matching pursuit method is based on series expansion of the signal by a set of elementary functions of orthogonal wavelets formed Hilbert transform pairs to match feature more effectively. Simulation testing and field experiments confirm that the proposed method is effective especially in extracting impulsive feature on high intensity noise, which matching pursuit method based on Discrete Wavelet Transform and other wavelet de-noising methods based on threshold and frequency-band, etc cannot do it completely.

In sheet metal forming, friction condition between sheet metal and mold is a very important problem for it influences the formability and the variation of stress, strain and thickness of sheet metal, and so on. Simulation experiments had been done to measure friction coefficients online at punch and die rounded corners under different process parameters during warm deep forming of magnesium alloy sheet. The results made it clear: temperature shows the greatest effect on friction coefficients, the effect of blank holding force (BHF) secondly, and no significant effect of lubricant on the friction coefficients. The friction coefficients at die rounded corner are larger than those at punch rounded corner. The dynamic changed friction coefficients models with temperature and BHF were fitted by the experimental data respectively, and they were added into simulation software through further development by user subroutine VFRIC using FORTRAN language to improve the accuracy of the numerical simulation.

Warm forming of magnesium alloy sheet has attracted more and more attention in recent years. Mechanics tension test has been made in this paper in order to study the constitutive relationship of ME20M magnesium alloy sheet at different temperatures and strain rates. And a constitutive relationship which includes a softening factor has been put forward. Warm deep drawing experiment and numerical simulation on ME20M magnesium alloy sheet have been made in which the attention was focused on the forming temperature. The results showed that the limit deep drawing height of ME20M magnesium alloy sheet can be dramatically improved as the temperature goes up, especially when the temperature was over about 250°C. Simultaneity, it is feasible and effective to add a material model into numerical simulation software by user subroutine.

Al-4.5Cu-3Ce alloy semi-solid slurry has been prepared by using slope vibration casting. The effects of the pouring temperature, slope length, vibration amplitude and vibration voltage on alloy solidification microstructure were researched. Experiments show that these parameters play a significant role on the alloy microstructure. The uniform, small equiaxed microstructure of Al-4.5Cu-3Ce alloy can be acquired by water-cooled copper mold casting at 680°C with slope length of 20cm, vibration amplitude of 2cm and vibration voltage of 80v. Its average grain diameter is 28.1um with average roundness coefficient of 0.82.

In semi-solid remelting process, the various stages of reheating temperature and isothermal holding time must be accurately controlled in order to obtain the uniformly distributed and small equiaxed grains microstructure. In this paper, a temperature control program was developed and the remelting process for Al-7Si-2RE aluminum alloy was carried out. The results showed that with the raise of reheating temperature and the extension of isothermal holding time, the liquid fraction increases, α-phase grain grows and becomes rounding in the process of Al-7Si-2RE alloy semi-solid remelting. The most reasonable process parameter of reheating temperature is at 585~590°C and its appropriate isothermal holding time are about 10~15min for the semi-solid Al-7Si-2RE alloy.

In engineering technology, it is necessary to compare different designs in an optimization project. Therefore a big problem is how to obtain finite element analysis (FEA) data involving different parameters and how to acquire optimization parameters from the results of FEA to solve the optimization problem rapidly. The parametric mesh (Paramesh) method, automatically based on history of complicated special surfaces, is developed to obtain many results of FEA involving different parameters. This paper is presented to demonstrate the method of parametric finite element analysis (PFEA). The optimization method of process parameters optimization is based on combining PFEA/ ANN (artificial nerve net)/GA (genetic arithmetic) to find out optimization parameters. This allows one to rapidly obtain optimization parameters during a design by doing FEA only once. The research indicates that the parameters optimization method based on PFEA/ANN/GA in the product design can short the product development cycle, decrease material consumption and guarantee product quality, etc.

A new technique using slope vibration casting process during heating and isothermal holding period to prepare Al-7Si-2RE alloy has been studied. The small, near-spherical and non-dendritic microstructure with the semi-solid processing requirements has been obtained. Experiments show that the cooling method, pouring process and the convection of melt caused by slope vibration had significant effects on the formation of near-spherical primary gains. The water-cooled copper mold casting with slope vibration at the temperature near liquidus can obtain Al-7Si-2RE alloy with small homogeneous equiaxed grains, the average grain diameter is 48.3μm, and the average grain roundness is 1.92.

In order to research the adhesion of sputtering protective coating of Gd.Gd substrates were differently coated with Cu and Al by means of DC magnetron sputtering technology. The characteristics of the films were investigated by scanning electron microscopy (SEM), EDS, and the adhesions of films were tested by tension test. The results show that the films of Al are smooth and perfect, the interferences between Al and Gd join together strongly, and the largest strength of adhesion is 27.6MPa in these tests on the optimize parameters through orthogonal experimental design. While the films of Cu are rough and bad, the interferences between Cu and Gd join together loosely, and the largest strength of adhesion is only 3.02MPa in these tests on the optimize parameters through orthogonal experimental design.

This paper aims to study the effects of rare earth Cerium addition on mobility, solidification shrinkage, casting microstructure and hot tearing tendency of Al-4.5Cu alloy. Results show that by adding appropriate rare earth Cerium into the Al-4.5Cu alloy, the viscosity of liquid metals can be reduced, the mobility of alloy can be increased, and the shrinkage during the solidification of liquid metal can be reduced. Further more, as the tendency of alloy dendrite is inhibited and the microstructure of the casting alloy is improved, the alloy can be purified, its thermal conductivity can be enhanced, and the hot tearing tendency of it can be decreased remarkably. It proves that when rare earth Ceriumaddition in Al-4.5Cu alloy is 4w%, the mobility of Al-4.5Cu alloy will be the maximum, and its volume shrinkage will be the least. Meanwhile, the grains of alloy are refined and round. The alloy also shows the lowest hot tearing tendency.

The effects of adding rare earth Cerium on Al-4.5Cu alloy microstructure, solidification range and volume changes in the solidification process are researched. Experiments show that rare earth Cerium will bring remarkable effects on the alloy microstructure, solidification and solidification shrinkage interval. When the quantity of rare earth Cerium is about 4 wt%, the solid-liquid two phase of Al-4.5Cu alloy will range from 640°C to 600°C. The grains of the alloy are refined, round. The volume shrinkage is only 68.6% of that without adding rare earth Cerium.

The semi-solid slurry of AlSi7 alloy was prepared by near-liquids cast processing. The effects of different content of RE on the cast performance and the semi-solid remelting performance in AlSi7 alloy was researched. The results indicated that adding RE will widen the AlSi7 alloy solid-liquid two-phase zone temperature and refine the grains, silicon will obvious metamorphoses. The best amount of RE is about 0.5%. Its semi-solid remelting organization is equilateral globular grains.

SSM(Semi-solid metal) forming has been developed to become a novel technology in the 21st century for the formation of near net shape components, competing with conventional casting and forging technologies. In this paper, the casting microstructure and its change during remelting of AlSi7Cu5 alloy casting by slope near-liquidus method were researched. Experiments show that it has a significant impact on microstructure by cooling method, the thermal conductivity of the casting mold and casting method. The microstructure of AlSi7Cu5 alloy obtained by slope near-liquidus method at 600°C is uniform and small equiaxed Its average grain diameter is about 55.2um, and its average grain size roundness is about 2.13. The reheated microstructure which can be applied in thixo-forming preferable will be obtained by keeping constant temperature 25min at 580°C.

A new unsaturated poly (ester–amide) viz phthalic anhydride–maleic anhydride–hexane diamine–ethylene glycol–neopentylene glycol copolymer was prepared by melt polycondensation and characterized after sealed end with benzyl alcohol. Mechanical properties and degradation behavior of the cross-linked unsaturated poly (ester–amide) were measured. Moreover, the hydrolysis behavior of cross-linked unsaturated poly (ester–amide) in 1.0 mol/L NaOH standard solution at room temperature was also studied. At the same time, preliminary biocompatibility under mice skin was evaluated. All the preliminary results suggested that the copolymer might be a potential bone internal fixation material.

Cu-4% mixed-powder consisting of rough copper powder and graphite powder was separately mechanical alloyed by high-energy ball milling. The phases and micrograph of these powders were determined by X-ray diffraction and scanning electron microscopy (SEM). The results show an increase in the lattice parameter of copper with milling times, up to a saturation value of about 24h; There was an absence of graphite reflections from X-ray diffractograms after longer milling times.