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In order to prepare the bone repair scaffold materials that could employ the sources of the injured bone, the bioactive HA and BMP-2 were added into the biomaterial PLLA. The four scaffold materials, PLLA, PLLA/HA, PLLA/BMP-2 and PLLA/HA/BMP-2 were prepared by electrospinning. The SEM results revealed that the morphology of the 7wt% PLLA fibers was better than the 5wt% PLLA fibers, and the HA nanoparticles were distributed uniformly in fibers. The calculated surface energy of the PLLA/HA/BMP-2 scaffold was higher compared with other three scaffolds, this result fit well with the result of MTT assay of the four scaffold materials, and the MTT assay showed that the MG63 cells on the PLLA/HA/BMP-2 scaffold material proliferated faster compared with the PLLA/HA or PLLA/BMP-2. It is logical to assume that PLLA/HA/BMP-2 scaffold material is a promising material for bony tissue repair.

To obtain high-performance alumina powder for high-tech application, a comparative study was carried out for the spheroidization of two types of alumina powder using radio-frequency argon-oxygen thermal plasma. The morphology, crystallography, and particle size distribution of spheroidized alumina powder were analyzed. The effect of feed rate on the spheroidization efficiency was investigated. The results show that when the powder flow rate was 35 g/min, the spheroidization efficiency reached up to 100%, and the alumina powder had perfect sphericity, while the spheroidization efficiency decreased with increasing powder flow rate. The X-ray diffraction analysis reveals that the spheroidized alumina powder had mixed crystal structures with a stable α phase and a part of metastable phase. The particle size distribution analysis shows that the particle size of the spheroidized alumina powder did not change obviously. These results will help us to better understand the process engineering of the spheroidization of ceramic powder using radio-frequency argon-oxygen thermal plasma, and provide simultaneously technical assistance for industrialization.

Analyze of university-industry-research cooperation’s characteristics which the university is the main target, and each case has been specifically addressed, characteristics of the cooperation were discussed, and detailed analysis of the relationship between the characteristics of the main features of each. From the perspective of their own cooperation feature, further discusses the characteristics of cooperation.

Independent component analysis is an efficient way to solve blind source separation, which has been broadly used in many fields, such as speech recognition, image processing, wireless communication system, biomedical signal processing etc. Independent component analysis for the traditional ways to solve the blind source separation problem only considers the non-Gaussian signal, without taking into account the time structure of the signal information. Proposed based on generalized self-related and non-Gaussian source separation method, the full account of the non-Gaussian signal and time structure information, to solve the blind source separation problem in the time structure of the signal. Finally, this simulation method is validated, the simulation results show that the method is effective and worthy of promotion.

The purpose of this investigation is to examine the machining behavior of cemented carbide tools in dry hard milling of cellular aluminium alloy (6N01) by experiments and finite-element analysis. From the machining point of view, Cellular aluminium alloy are often considered as poor machinability materials. Milling tests were carried out by using a three-head milling machine and a milling force measuring device. For this purpose, both microscopic and microstructural aspects of the tools were taken into consideration. Meanwhile, the cutting forces and the noise intensity are also considered in the experiment. Results show that cutting forces vary greatly with the experimental cutting parameters. Additionally, the noise field intensity increased greatly as the feed rate increased. Analysis indicated that the major tool wear mechanisms observed in the machining tests involve adhesive wear and abrasion wear.

The block copolymer solutions were prepared by dissolving polyethylene glycol/polybutylene terephthalate (PEG-b-PBT) with different intrinsic viscosities in chloroform. The composite ultrafine nanofibers of PEG-b-PBT and PEG-b-PBT-HA(hydroxyapatite) were obtained by gas-electrospun, and were characterized by scanning electron microscopy (SEM), horizontal attenuated total reflectance for Fourier transform infrared spectrometer (HATR-FTIR), dynamic contact angle measuring apparatus and differential scanning calorimetry (DSC). The gas-electrospun fibrous membranes, which were made of ultrafine fibers with average diameter 180-1200nm and well-interconnected pores, were possessed with high surface-to-volume ratio and excellent hydrophilicity. The above results strongly suggest that fibrous membranes combine advantages of synthetic biodegradable polymers and nanometer-scale dimension for mimicking the natural ECM, and may represent an ideal tissue engineering scaffold, particularly for soft tissue, such as skin and cartilage tissue engineering scaffold.

In this work, the composite nanofibers of polybutylene terephthalate/polyethylene glycol (PEG/PBT) with difference intrinsic viscosity and different ratio of the hard-segment to the soft-segment were obtained by gas-electrospun. The PEG/PBT-HA composite nanofibers were also obtained by gas-electrospun. PEG/PBT and PEG/PBT-HA composite nanofibers were characterized using scanning electron microscopy (SEM), horizontal attenuated total reflectance for Fourier transformation infra-red spectrometer (HATR-FTIR), dynamic contact angle measurement and differential scanning calorimetry (DSC). The results strongly suggest that this synthetic matrix combines with the advantages of synthetic biodegradable polymers, nanometer-scale dimension mimicking the natural ECM, may represent an ideal tissue engineering scaffold, especially for soft tissue, such as skin and cartilage tissue engineering scaffold.

An ECMP slurry screening protocol is proposed based on inhibition efficiency of inhibitor in copper static corrosion test, aiming at enhancing the planarization efficiency of copper ECMP slurries. The elctrochemical properties of copper in electrolytes including H3PO4 and BTA with different concentrations are studied basing on Linear Sweep Voltammetry (LSV) and chronoamperometry under static corrosion states. According to analysis of the anodic current, material removal rate (MRR) and inhibition efficiency of BTA, an electrolyte formula of 30 wt% H3PO4+0.01M BTA is sort out and the anodic potential on copper should be set below 0.5 V.

Nanocomposite tool materials are developing very fast in engineering field for their highlighted advantage in mechanical properties and stability under high temperature. However, there are lots of puzzles to be discussed in the materials design theory and the fabrication processing due to the difference between the traditional materials and the nanocomposite. Therefore, in this paper, a new nanocomposite tool materials design method has been proposed based on the interface strengthening theory. The sintering temperature and the soaking time could be optimized based on the interface strengthening theory and the relative density of the tool materials. Meanwhile, a series of experiments were carried out to fabricate the nanocomposite tool materials under the guider of the interface strengthening theory. Results showed that experimental data agreed well with the calculation and the model was proved to be correct.

The purpose of this investigation is to recognize the wear mechanisms of cemented carbide tools in dry hard turning of stainless steel (1Cr18Ni9Ti). From the view point of machining, stainless steels are often considered as poor machinability materials. Turning tests were carried out by using a CA6140 lathe and a cutting force measuring device. For this purpose, both microscopic and microstructural aspects of the tools were taken into consideration. Meanwhile, the cutting forces are also measured in the experiment. The chips were analyzed by scanning electron microscopy. The machinability of 1Cr18Ni9Ti austenitic stainless steels is examined in terms of tool life and cutting parameter presented in this paper. Results show that cutting forces vary greatly with the experimental cutting parameters. Analysis indicated that tool wear mechanisms observed in the machining tests involve abrasion wear, thermal and fatigue shock wear and adhesive wear.

Mesoporous carbon with high surface area and ordered structure was synthesized via a nanocasting process using mesoprous MCM-41 silica as a template and sucrose as a carbon precursor. Sample was characterized by XRD, SEM, TEM and nitrogen adsorption. The results show that the templated carbon has a BTE surface area ∼1200 m2/g, a pore volume ∼1.0 cm3/g, and a bimodal porosity centered at around 4 nm and 46 nm.

A membrane support provides mechanical strength to a membrane top layer to withstand the stress induced by the pressure difference applied over the entire membrane and must simultaneously have a low resistance to the filtrate flow. Due to their low thermal-expansion coefficient and good thermal-shock resistance as well as excellent mechanical and chemical stability at elevated temperatures, porous SiC ceramics have been widely used as catalyst supports and hot-gas or molten-metal filters. In this work, the influence of the particle size, sintering time and sintering temperature on the porosity and permeability of supports made by dry-pressing of micron-sized SiC powders is investigated. The present work presents a comparison of properties and performance data for samples made with different particle size. The effects of sintering time and temperature were analyzed in view of overall porosity and permeability. From calculations it becomes clear that optimum values exist for the material properties of the support.