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The micro-patterned TiO2 nanotube has been anticipated for potential application for cardiovascular implanted devices for its excellent drug loading/ release function and biocompatibility. However, its mechanical behavior has rarely been studied as the cardiovascular devices. The tube length is a crucial factor which not only decides the drug loading ability but also influences the devices’ mechanical behavior. Therefore, in this work, the micro-patterned TiO2 nanotubes with different tube length (MNT2, MNT4 and MNT6) were fabricated, and their surface energy, residual stress, tensile tolerability and blood flow shear stress tolerability were determined, respectively. The results showed that the microstructure reduced the surface energy of the nanotubes surfaces, enhanced or reduced surface tensile tolerability when parallel or vertical to the strain orientation, and also increased the nanotubes surfaces residual stress; In addition, both micro/nano and single nano surfaces possessed good blood flow shear stress tolerability. These results indicated that the micro/nano surfaces possesses excellent mechanical properties for surface modification of cardiovascular devices.

The single stage porthole die extrusion was largely applied in our research and industrial production. Two stage porthole die for a hollow aluminum tube, which added a pre-porthole die in front of the conventional porthole die, could slow down the metal deformation rate and control the metal flow uniformity. We performed a simulation of hollow aluminum extrusion in single stage porthole die and two stage porthole die. Through a series of numerical simulation based on Forge software, the advantage of two-stage porthole die extrusion, such as the surface quality of extruded profile, extrusion force, welding quality and die stress, was studied. The results showed that the pressure of welding and required extrusion force decreased and the surface quality of the extruded profile would be improved. Thus, we could prolong the work life of mandrel root by the means of this method.

Thermal insulation materials are the most crucial composition in the external wall insulation technology. For the poor fireproofing of organic thermal insulation material, the inorganic/organic composite foamed thermal insulation material is prepared by optimizing inorganic foaming reaction. Inorganic polymer cross-linking system is used as the skeletal structure of foamed composite material and the modified urea-formaldehyde resin with excellent fire resistance is used as toughening material. The analysis results indicate that the composite structure with metal phosphate as skeleton and modified urea-formaldehyde resin as toughened-membrane is formed during the preparation process of the composite foamed material. The property test shows that the thermal conductivity is 0.0389W/m·K, the compressive strength is 180kPa, temperature rise in furnace is less than 20°C and the mass-loss rate is less than 50%. What is more there is no obvious flame appeared in the building materials incombustibility test. Therefore the composite foamed material can be judged to be A-grade incombustible thermal insulation material.

In order to improve the cell biocompatibility of pure iron surface as cardio-vascular stent material, Fe-O film was deposited on single crystal silicon by unbalanced magnetron sputtering. Human umbilical vein endothelial cells were seeded on the 316L SS, pure iron and Fe-O film surface, whereafter cultured in vitro. Adhesion behavior was detected after 2 h incubation. Cell morphology and proliferation activities were assessed at 1, 3 and 5 days. The results show that the endothelial cells are easy to adhere and spread on the surface of Fe-O film. Compared with 316L SS samples, the cells count and area coverage of Fe-O film in 1 and 5 days make a difference significantly. These results demonstrated that the Fe-O film prepared by unbalanced magnetron sputtering technique has good cytocompatibility.

Water curtain efficiency test is the key method to evaluate the tightness and reliability of water curtain system. This thesis taking the cavern in Yantai as an example, based on the data of three different hydrodynamic condition stages during efficiency test, in combination with the important judgment parameter of water curtain efficiency-critical pressure value, the low efficiency of rock area was revealed by analyzing and evaluating the conduction effect of fissure water pressure. In order to improve the efficiency, drilled additional boreholes in low efficiency area. At last, through the test to evaluate efficiency improvement of new drilled boreholes. The test result shows that: the water curtain efficiency test can able to accurately determine the low efficiency area in rock mass, additional boreholes can significantly improve the pressure of low efficiency boreholes and can achieve the tightness requirements of cavern.

The flexural behavior of reinforced concrete beams strengthened by CFRP is analyzed by using the way which connected tests with finite element simulation.First,through the test to get the load data of one unstrengthened and one strengthened reinforced concrete beam.Then,the finite element model is carried out based on Ansys finite element analysis software.The reinforced beam carrying capacity is improved based on the test data and finite element calculation results.Steel bars stress change curve, CFRP stress curve and the load displacement curves are in good agreement with experimental results.

Novel pHsensitive methacrylate-based (co)polymers with pendent tertiary amine groups were prepared by free radical polymerization of monomer 2-(dimethylamino)ethyl methacrylate (DMA) and 2-(Dibutylamino)ethyl methacrylate (DBA). These polymers are pH sensitive in aqueous solution, which was studied by titration, transmittance measurements experiment. The pH responsive polymers dissociate at lower pH value because of the electrostatic repulsion and aggregate above their pH responsive value induced by hydrophobic interaction of pendent group. The pH responsive value of (co)polymers can be controlled by ratio of DMA and DBA. These novel polymers have great potential application for biomedicine.

Biggish animal models were applied in perfusion system for ex vivo research. But the disadvantages is the needs for more research funding and better surgical skills to perform which many researchers lack. A minor-caliber vessel perfusion system for ex vivo was designed and constructed to simulate pulsatile situation in vivo. The parameters mimicked the physiological measures of New Zealand rabbit. Pulse is 250 beats per minute. Diastolic blood pressure is 12.666KPa, and systolic blood pressure is 14.665KPa. The vessel perfusion system can regulate pulse pressure, the state of laminar flow, and shear stress. To culture several vessels simultaneously for control, the pressures data of 4 baths was analyzed with one way analysis of variance. The results show that the perfusion system is stable, and pressure difference of 4 baths is not significant.

In this paper, to meet the security need of electronic records under the digital office environment, technological requirement of the security of electronic records is analyzed, and the security model of electronic records based on IPSec protocol is designed and tested under Windows 2000 Server system. As is showed in the test result, this model can secure the electronic records based on digital office environment.

A novel pH sensitive cadmium sulfide quantum dot (CdS QD) was prepared by a coprecipitation method in the presence of pH sensitive poly (2-(dimethylamino) ethyl methacrylate)-co-poly (2-(dibutylamino) ethyl methacrylate)(PDMA-PDBA) copolymer. CdCl2and Na2S were mixed in aqueous media in the presence of PDMA-PDBA. The amine groups of PDMA were anchored on the surface of the formed CdS nanoparticles, whereas the PDBA segment was anchored on the surface to form a hydrophilic palisade at low pH environment, thus turn on the fluorescence CdS QD probe; at high pH value, PDBA segments precipitate and turn off fluorescence because of the phase separation. This novel pH sensitive fluorescene CdS QDs probe have great application potential for target imaging of cancer.

To meet the requirement of electric control diesel engine operation optimization, an online calibration system of diesel engine is designed based on the principle and the way to communicate of CAN-Bus. This Calibration system found communication accurate and quick, which researching of software is based on Windows platform, VC++6.0 software and modularization designed [1]. At last electronic control system simulation platform experiments demonstrate that data transfer function is reliable and steady and bench tests testify that the calibration system can calibrate diesel engine practical.

This article took ISG Hybrid Electric Vehicle (HEV) as the target, studied its different engine starts under traditional control and μC/OS-II multitask real time operating system. Through the experimental comparisons in engine start strategy and control method, this study reached the conclusion that, the engine start process under μC/OS-II multitask real time operating system is more precise and smooth than that under the traditional control. In this way, multitask real time operating system can help reduce the fuel consumption and emission in engine start.

The paper introduces a high precision ultrasonic heat meter design based on time-difference method. It analyzes and researches the measure theory of time-difference ultrasonic heat meter, and presents a piecewise interpolation method to calculate the flow. With the low-power chip as the microcontroller, the system adopts high-precision time measurement chip TDC-GP21 for flow measurement as well as the temperature measurement. Compared with traditional heat meter, it is of low power consumption and high measurement precision, and the tests show that the results meet the heat meter industry standard second order accuracy.

With the progress of science and technology, the image resolution of monitoring systems is entered the Full-HD (High Definition) era. The Full-HD refers to resolution of 1920X1080 (1080p), and the image refresh frequency is 30fps (Frames Per Second). Therefore, this thesis uses FPGA as image system processor, as well as uses AFE to implement a camera module. First, the dual-channel serial signal from AFE is converted into single-channel parallel signal, and the image is processed following our image processing procedure before charting and export. The image processing procedure includes AEC, auto color balance, color filter array interpolation, color correction, noise filter, gamma correction and dynamic range correction. Our algorithm counts information instantly, and calculates better correcting function content, so that we can display the brighter and darker parts of images clearly in different environments. Compared with a part of CCD digital cameras on the market, our ISP has better performance in SNR. Finally, the AWB mean error of our ISP design is less than 0.02%, it is difficult to be perceived by human eyes.

The conventional machining method for silicon nitride ceramics has low machining efficiency, prone to cracking, chipping and other defects. In this paper, the author carried out a study on the influence of ultrasonic vibration grinding on surface quality of silicon nitride ceramic, and carried out ultrasonic vibration grinding process test for silicon nitride ceramic and conducted the analysis of influence of this machining process on surface quality with orthogonal test. The test results showed that the influence on surface roughness decreased in the order of spindle speed, feed rate, cutting depth, and amplitude of vibration.

In this paper, with a 92,500 ton bulk-carrier being mainly taken as an example, the preparing design of launching processing scheme on the horizontal berth is discussed. Calculation of needed hulling force and strength examination of hoisting pad are done, and then the structural strength of hoisting pads and their stiffening structures are analyzed with the aid of finite element technique. Once the total assembly of hull is completed on the berth, the launching weight should be calculated and proper number of box-beams should be determined. Sliding frictional media used between box-beams and slipping-rails should be selected, and according to combined frictional coefficient, the needed pulling force by which the hull may be hoisted forward securely should be fixed. In order to assure the safety of ship in the period of launching, strength examination calculating for hoisting pads and stiffening members should be done by means of finite element method as soon as their types and assembling positions are determined, so that the strength of hoisting pads and stiffening structures should be able to meet the requirements. Owing to that this ship having being successfully launched, the reliability and usability stated in this paper have being verified. Therefore, it is of quite value to be referred in technical analysis for launching on the horizontal slipway.

When comparing with ship construction within newly-built docks or on tilting slipways, ship constructing on the flat earth method can be said to be a new ship-building technique by which ship is built on a platform and launched with the aid of floating-dock or barge. Some obvious advantages of this technique are such as less investment in basic facilities, low production cost, high production efficiency, wide applicability of ship types, ability to overcome the bottle-neck effect of berths and docks. In this paper, a bulk-carrier being taken as an example, the design of launching processing scheme on the horizontal shipway includes calculation of launching weight and determination of hoisting force during the whole towing period. The whole towing process of hull can be divided into three stages, the first is from the static state to the moment of beginning to move, the second is from the initial position of movement to the front of slipway onto which the hull is predicted to be pulled, and the third is from the front of slipway to the designated position on the floating dock. Subsequently, after the hull being sealed and positioned correctly, the floating dock for launching may be towed to deeper water zone and the hull can be buoyed up on the water surface, and the whole launching process can be completed. From the research, the conclusion is made that the launching technique of this paper is available and feasible. Especially, this paper is the initial application of this method on the 15000t launching ship home and has the epoch-making sense.

Retracted paper: Since AB SLC500 PLC does not support the Profibus protocol, it can not communicate with Profibus network. In order to realize the fast and accurate communication between these two, this thesis studies the Profibus protocol and develops the Profibus application program in the Flex I/O module. Thus the communication between SLC500 PLC and Profibus network is realized. Compared with the applying of SLC500 to control the other equipments and network, the applying of the Flex I/O module promotes the controlling efficiency and responding rate and realizes the complete control of the controlling system. The result of this research shows that this plan can ensure the accuracy, reliability and efficiency of the data transported.

This work is based on a typical RC frame that was closed to the epicenter and collapsed during the Wenchuan Earthquake. The seismic collapse resistance of the frame was strengthened by attached substructures, including conventional brace, buckling restrained brace (BRB) and viscous damper. Collapse fragility analysis based on incremental dynamic analysis is implemented for each strengthening scheme to compare their effects and to analyze the influence of critical parameters. The results show that the viscous damper performs better than the BRB, and the BRB performs better than the conventional brace. With the same strengthening parameters, the A-shaped bracing scheme is better than the X-shaped scheme.

This paper describes FRP boat hull for specific construction process using the vacuum infusion process, and between the different processing sample strength are compared, and then to get the optimal construction scheme, which can be the reference to the yacht building in the future.

In order to reveal the design regularity for the various sizes of mechanical heart valve(MHV), the theoretical and parametric finite element method (FEM) were adopted to investigate the influence of the MHV pivot distance on the valve performance in this paper. Result shows that the characteristics of central flow can be improved for all sizes of valve with the increasing of the pivot distance, and the acceptable hydrodynamic performance of the MHV designed in this method was also shown in the valve pulsatile flow test, which proved that the parametric method is a useful tool for MHV design.

In this paper, in order to optimize the extrusion die action and to control quality of an industrial large Al-profile, the effects of die bearing band on the metal flowing behaviors are analyzed by applying some special methods, including designing the bearing band of the die as inclined plan and designing the geometry model as detachable structure. The velocity field showed that the metal flowing velocities in central and left-side locations were higher than that in groove location. The reasonable size-configuration of the extrusion die bearing band was obtained, and the defect of the right-direction bending was able to be removed effectively. The inclined bearing band structure, detachable geometry model and configuration method based on velocity balance proposed in this paper provided a valuable reference to design and to optimize this kind of solid Al-alloy large profile.

The Bileaflet Mechanical Heart Valve (BMHV) has been the most successful replacement mechanical heart valve, and is currently the most commonly implanted mechanical valve. Although the BMHV is an improvement over previous mechanical heart valves, there are still serious associated complications with its use that must be eliminated. After the completion of the processing and surface modification, heart valve ring and heart valve leaflets constitute a single whole with mechanical method to achieve its function process. In order to ensure that the heart valve is stable and reliable in service, it is particularly important to improve the assembly quality. The theoretical analysis and simulation used of ANSYS Workbench software for the behavior of the heart valve assembly have been done, the experimental results were verified by testing apparatus, which is a helpful tool used to simulate the new structure of the heart valve assembly, and play a certain significance to improve the accuracy of the assembly.

Artificial mechanical heart valve (MHV) replacement is the common cardiovascular surgical procedure, yet its effect is far from satisfaction. Most important reasons lie in the model design and choice of the materials in the fabrication of the prosthetic heart valves. Based on systematic design methodology of TRIZ theory (Russian acronym for Theory of Solving Inventive Problem), the device structure is analyzed by comparing the past successful designs generated during the evolution of MHV. This paper represents a modeling technique integrating the well-established TRIZ with the conflict and contradiction modeling, substance-field and product functional analysis tools and provides some important trends in evolutionary development of production systems in MHV design. By analyzing the structural behavior and material performance, a complex case study from the research of different structural patterns and characteristics of current tri-leaflet modeling shows the validity of TRIZ theory to guide MHV design.

：(Ti, Al)N films were deposited on high-speed steel (HSS) by filtered cathodic vacuum arc (FCVA) technique under a nitrogen atmosphere. X-ray diffraction was used to characterize the structure of the films .The micro-hardness was tested. The result shows that the crystal structure and mechanical properties of (Ti,Al)N films are strongly dependent on the nitrogen partial pressure. The structure of (Ti,Al)N films is composed of Ti2N phase, TiN phase and TixAly phase. The hardness increases to a maximum at the nitrogen partial pressure of 8•0×10-2Pa, then decreases with increasing nitrogen partial pressure.

A hysteretic model of conventional steel braces consisting of 18 parameters is proposed. This model is able to simulate the hysteretic behavior of conventional steel braces accurately. The collapse-prevention strengthening effect with steel braces for a typical reinforced concrete (RC) frame that was close to the epicenter and collapsed during the Great Wenchuan Earthquake is discussed via push-over analysis and collapse fragility analysis based on incremental dynamic analysis. The result could be referred to for the seismic collapse prevention design of RC frames.

The proposal of this investigation is the optimization design of bulbous bow-lines for a container vessel. The results of wave-making coefficients and relative data of wave-making field both from computation based on Green function method and Michell integral method are provided for 7 different designs of bulbous bow lines respectively in this paper. According to the minimum energy from the sample of average wave-making energy for each design of bulbous bow-lines, which is to be objective function in this computation, the geometric parameters for optimization lines of bulbous bow can be determined. Adopting CFD method, it is respectively calculated that the average wave energy change with the ahead extendable length of bulbous bow, the height above the baseline of bulbous bow and the transverse area of the bulbous bow at fore pole. By above three change curves, the optimization shape of the bulbous bow is gained. The resistance components and the wave-field for wave-making for ship hull by using CFD method have been validated based on corresponding model test results. Therefore, the optimized bulbous bow-lines can be used in the ship design practice.

In this paper, taking a 7000 TEU container ship as an example, research on optimization design of mold lines of bulbous bow for container ships is carried out. Firstly, geometric parameters of bulbous bow are selected to be as variables to construct 7 computing molds, then CFD methods are employed to calculate ship resistance and parameters of wave field generated by ship moving, as well as Michell integration is used to determine the coefficient of wave-making resistance. Minimization of resistance is taken as the aim function to obtain the optimum geometric parameters of mold lines at bow. The results of mold testing express that the mold lines of bulbous bow for container vessel optimized by above methods are credible and valuable for engineering practice.

Urbanization in Southwest China, an extensive mountainous region, has been unprecedentedly rapid in the past two decades, particularly with the implementation of “Great West Development”. However, most present studies on urbanization of Chinese cities are limited to coastal area. Little is known about the urbanization pattern and underlying mechanism in this region. The main purpose of this research is to analyze the process of rapid urbanization and its impact on mountain environment, using Chongqing, the well known “mountain city” in China, as an example. Four time-series satellite images were employed to extract the landscape data. The result was assessed by several “landscape metrics”. The research also investigated how complex natural factors as well as socio-economic factors exerted influence on the urbanization. Based on examination of present landscape, a planning model which was believed suitable for mountain urban development was proposed.

Nanostructured WC-17Co coating was prepared by means of High Velocity Oxygen Flame (HVOF) technique. When eroded with quartz sand, the erosion wear resistance of nanostructured coating is better than that of 1Cr13. The loss of Co-rich phase dominates the main failure mechanism, following with minor peeling of WC particles.

In order to discover the formation mechanism of carotenoid derived aroma, which has been wildly used on protection of crop against insect attacks, the full-length cDNA of an Artemisia annua carotenoid cleavage dioxygenase (AaCCD1) was cloned by rapid amplification of cDNA ends. The function of AaCCD1 was characterized by expression of AaCCD1 in a strain of E. coli accumulating carotenoids and enzyme assay in vitro. The completed open read frame of AaCCD1 was 1629 bp and it encoded a 542-amino acid protein with a 77% amino acid identity to Arabidopsis thaliana CCD1, a predicted molecular mass of 61.04 kDa and a pI of 5.8. AaCCD1 efficiently cleaves carotenoids and regulate the formation of terpenoid compounds. This is the first time to report the cloning and identification of carotenoid cleavage dioxygenase from Atemisia annua, which will play a great role on understanding the regulation of volatile compounds.

Nanostructured WC-17Co coating was prepared by means of High Velocity Oxygen Flame (HVOF) technique. Characteristic of nano-structure of the coating was analyzed. The coating seems to be of lamination structure formed by fully or partially melted powder. It shows that the coating consists of melted and recrystallized zone, semi-molten zone and un-melted zone. Amorphous phase and nanocrystalline phase co-existed in the coating is due to the rapid heating and cooling during spraying. The nanostructured coating possesses excellent mechanical properties, which are closely related to the unique nanostructures existed in the coating.

A phase-locked loop (PLL) control system based on field programmable gates array (FPGA) is proposed through analyzing the model of three-phase unipolar-driven BLDCM (brushless direct current motor) to enhance the reliability and accurate steady-state speed for magnetically suspended control moment gyroscope (MSCMG). The numerical operation module, PLL module and current-loop control module are designed based on FPGA using very-high-speed integrated circuit hardware description language (VHDL) to realize the control law of the digital system. The pulse width modulation (PWM) generating module for Buck converter, the commutation signal generating module for the inverter and ADC module are designed for driving the motor and sampling the current signal. The PLL is analyzed and optimized in the paper and all the modules are verified using the software of ModelSim and the experiments. The simulation and experiment results on BLDCM of MSCMG show that the stability of the motor velocity can reach 0.01% and 0.02% respectively by the PLL technology based on FPGA, which is difficult to be obtained by conventional proportion integral different (PID) speed control.

Diamond-like carbon (DLC) films have been given great attention in the last twenty years and applied in many fields due to its super mechanical property. In this paper, DLC films were prepared by filter cathodic vacuum arc (FCVA) deposition under different negative bias voltage. No spalling was found in all of as-prepared DLC films. X-ray photoelectron spectroscopy (XPS), Raman spectra were employed to analyze composition and structure, the results showed that as-prepared DLC films had tendency of graphite with increase of negative bias voltage. Mechanical properties were characterized by micro-hardness and pin-on disc tests, the results showed that the hardness of DLC films decreased with bias voltage, but still kept good wear resistant.

Nanostructured WC-17Co coatings, nanostructured WC-12Co coatings, conventional WC-17Co coatings were prepared by means of High Velocity Oxygen Flame (HVOF) technique. The characteristic of powders and coatings of nanostructured WC-17Co coatings, hardness of different coatings, distribution gradient of the hardness of the nanostructured WC-17Co coatings in the depth direction, fracture toughness and interface fracture toughness of different coatings, residual stress of different coatings, different phase and distribution of WC phase in the depth direction were investigated. The results indicated that the micro-crack is spread along the phase interface where the brittle phase are more in the Co rich area , where there are more different properties in the Co rich area and W rich area, where there are more defects close to the intend end in the W rich area, even spread through the WC particles in microcosmic and the different residual stress of different phase are because of different melting point and different expansion coefficient , so the WC, W2C produced compressed stress, the Co6W6C produced tensile stress. The residual stress manifested from higher to lower in the depth direction of the coatings.

The geotechnical test can't be applied to sand as the original sample is difficulty to collected by drilling, so the cohesive strength C of sand can't be acquired in geotechnical test. Generally speaking, according to the Mohr–Coulomb law, C=0. From the numerical point of view, when the slope angle is greater than the internal friction angle, the global stability of slop can’t meet the requirements of standard. However, that’s not the case in fact. In practice, the slope angle can be determined by means of analogy. Although successful experiences have obtained, there still exist some potential hazards. In this paper, we have made some studies on the cohesive strength of sand based on the control of instability of a deep foundation in Xiang'an District, Xiamen, China.

The safety and comfort play more and more important roles in foundation wear design. In this paper, the change of skin blood flow under pressure is focused on. Three healthy young females were recruited to participate in the experiment. The subjects were required to wear girdles of different design, and the pressures and skin blood flow at five feature points were measured by using AMI system. Moreover, pressures of different magnitudes were exerted at the convex points of pelvis and hip by using the AMI pressure chamber, the change of skin blood flow under these pressures were observed. Some conclusions were drawn as follows: the pressure distribution under girdle was not uniform on skin surface; SBF increased under pressures, but it turned to decrease if pressure was very high; the skin pressure could be eased to varing degrees by the soft tissue, and SBF was influenced by the pressure exerted on capillaries rather than skin pressure.

In this paper, we discussed the package structure design of in-door air conditioners aiming the current status and problems. Box types such as 0201, 0203, and improved 0440 are used, and comparison experiments are carried out on compressive strength of empty boxes to optimize the structure design. By improving product package to increase efficiency, can effectively reduce product cost, and assure product quality.

In this paper, both geometrical and electronic properties of rutile TiO2 (110) surfaces have been investigated using First-Principles Density-Functional calculations with CASTEP code, the model of stoichiometric surface is a (2x1) super-cell which has 12 atomic-layer slabs with the bottom 6 held fixed, the bridging-oxygen vacancy surface has been constructed by removing a neutral bridging oxygen atom from this surface. For the stoichiometric surface, the atom relaxations are: Ti6f (+0.2865Å), Ti5f (-0.1039Å), O3f (+0.2433Å) and Ob (+0.0075Å), we find no reconstruction and no surface states in the band gap, the density of states (DOS) is similar to the bulk except the lower conduction band intensity, in accord with recent experiments. Whereas, as a result of bridging-oxygen vacancy, the atom relaxations exchanged and reconstruction occur. The 2 excess electrons left behind removal of one bridge O atom are localized on the Ti-t2g conduction band orbitals, convert some of the Ti4+ ions into Ti3+ ions and result a compensatory shift in the Fermi level. The band gaps we calculated for stoichiometric surface is similar to the bulk, but its increase can be found for Ob vacancy surface.

An approach to chemical recycling of carbon fiber reinforced epoxy resin cured with amine has been investigated. Amine cured epoxy resin was decomposed totally when it was treated with nitric acid solution under certain conditions. The impacts of nitric acid concentration and decomposition temperature on recycling method were studied with decomposing time and the performance of carbon fiber as indexes. Epoxy resin matrix decomposed entirely after 23hrs at 95°C in the 8mol/L nitric acid solution. Scanning electron microscopy analysis (SEM) and monofilament strength were used to characterize the recycled carbon fibers.

Low hemocompatibility is a major problem of biomaterials that come in contact with blood. Surface modification has become an important way to improve the hemocompatibility of medical implants and interventional devices. Recently, researchers attempt to investigate the possibility of silicon oxynitride (Si-N-O) films to be applied as novel coating of blood-contacting biomaterials. However, no detailed investigation has been conducted. In this study, our work was focused on the optimization of the hemocompatibility of Si-N-O films prepared on single-crystal silicon wafers by unbalance magnetron sputtering (UBMS). The structure and chemical composition of films were characterized by X-ray photoelectron spectrometry (XPS), and their physical chemistry property was characterized by contact angle measurements. Platelet adhesion test was performed to investigate the platelet adhesion and activation. Our results suggested that films composed of Si3N4 and SiOx (x

In this work, the PCS/CS/HA composites with different weight ratios were prepared through a co-precipitation method. The properties of these composites were characterized by means of the XRD, the IR, the SEM and the bending strength test. The value of bending strength of the PCS/CS/ HA composite with a weight ratio of 10/30/60 was measured about 34.93 MPa which is 1.6 times high of the cancellous bone. The composite is appropriate to be used as materials for bone tissue engineering.

The biological modification of biomaterials surface was an important means for surface endothelialization. In this work, an extracellular matrix-like (ECM-like) surface modification was developed for inducing endothelialization on titanium cardiovascular implant surface. To solve the problem of antibody denaturing caused in the randomly immobilizing, cluster of differentiation 34 (CD34) antibody was directly immobilized on titanium surface using a layer-by-layer self-assembly (LBL) technique. The biological behaviors of the endothelial progenitor cells (EPCs) on modified titanium surface were investigated by in vitro cell culture experiment. The results showed that the avidin, biotinylated protein A and the CD34 antibody were successfully assembled onto the NaOH etched titanium surface. The results of cells experiment suggested that the CD34 antibody immobilized surfaces promoted EPCs attachment and capture in vitro. It was believed that the response of adhesion, proliferation, differentiation of EPCs to titanium surface was regulated by modifying the surface chemistry which controlled the cell-biomaterial interactions. This work provided a surface biomodification means to increase the biocompatibility of titanium-based vascular implant surfaces.

In the current study the role of plasma treated nano titanium dioxide particles and strain rate on the tensile properties of plasma treated nano TiO2 particles/PP/PLA nano-composites filaments (PTNTOPPCF) was studied. The experiments included tensile tests and differential scanning calorimetry (DSC). The addition of the plasma treated nano titanium dioxide particles into PP/PLA caused a change in Young's modulus and yield stress of the composites. Strain rate sensitivity of the PTNTOPPCF changed as plasma with and without oxygen treated nano titanium dioxide particles was added to it with different percentage of weight. It was increased with more PLA, MAH, and higher flow rate of oxygen. Activation volumes ranged in 4−40(nm)3 for true nanocrystalline material estimated by the Eyring equation, which were changed un-monotonically with oxygen plasma treatment.

In the present paper, Cr, CrN single-layer films and Cr/CrN multilayer films were deposited on iron and silicon wafer substrates by means of unbalanced magnetron sputtering. The film thickness was measured using surface profile meter. The porosity ratio was calculated using coulometric method based on the polarization curves obtained in the 30g/L NaCl solution at room temperature. Moreover, the corrosion resistance of the sample in a 350°C water vapor atmosphere was also analyzed. The thickness of all films ranged from 1.03 to 1.54 micrometer. The porosity ratio of the Cr and CrN single-layer film were 3.72% and 5.83%, respectively. The porosity of the Cr/CrN multilayer film decreased to 0.39%. The results showed that the Cr/CrN multilayer films had better protection than the Cr and CrN single-layer films.

For an application as biomedical materials of high performance with a good biocompatibility, the Ti-O film on Si (110) wafer substrate has been synthesize by means of unbalance reactive magnetron sputtering method and modified by phosphorus ion implantation and succeeding vacuum annealing. X-ray diffraction (XRD) results indicated that such prepared Ti-O film had a rutile structure. X-ray photoelectron spectroscopy (XPS) analysis demonstrates the effect of P ion doping. The contact angle test and sheet resistance results showed that titanium oxide film and phosphorus-doped titanium oxide film became more hydrophilic and higher conductance after annealing. The morphology and roughness of the surface have been investigated using SEM. Antithrombotic property of the titanium oxide thin film was examined by platelet adhesion tests. The results showed that the undoped Ti-O films and the P implant and annealing at 900 °C Ti-O film had good blood compatibility.

Si-N-O films have drawn researcher’s much attention recently due to their potential superiority in blood compatibility of biomaterials. In this paper, Si-N-O films were synthesized on silicon substrates by pulsed reactive unbalanced magnetron sputtering a single crystal silicon target with high purity in a mixture atmosphere of Ar and N2. XPS and FTIR results showed the Si-N-O films synthesized at higher N2 flux could be described to random bonding model (RBM). In RBM, the Si2p existed in the form of a-Si3N4 and SiNνO4-ν (ν=0,1,2,3,4) components. Platelet adhesion behavior on Si-N-O films was assessed by platelet adhesion test and Lactate dehydrogenase (LDH) assay, qualitatively and quantitatively separately. The correlativity of film chemical structure and blood compatibility was investigated. The results of platelet adhesion and activation showed that the RBM film with higher N/O ratio exhibited favorable blood compatibility. It was shown that the Si-N-O film with specific composition and chemical bonding state was superior in blood compatibility compared to low temperature isotropic carbon (LTIC).

In order to improve the abrasion property of polyoxymethylene (POM)，diamond like carbon (DLC) film was deposited on POM substrate by the method of magnetic filtered cathodic vacuum arc deposition (MFCVAD). X-ray photoelectron spectroscopy (XPS) showed that the sp3 fraction decreased with the negative bias voltages increased. According to the result of the nano-indenter, the hardness of POM plates coated with DLC films was significantly harder than POM substrate. The results of ball-on-disc tribological testing demonstrated that the hardest DLC film had the lowest friction coefficient (0.11). The evaluation of in vitro platelet adhesion test indicates that the numbers of adhered and activated platelet on the DLC film deposited under the condition of 0V and 9min were remarkably decreased compared with that of the untreated POM.

Percutaneous transluminal coronary angioplasty(PTCA) has become increasingly important in the therapy of coronary artery disease. However, the high restenosis occurrence of 20%～30% in patients limits the applications of this method, but the pathogenesis of restenosis has not yet been fully understood.In this paper, static organ culture system was set up to study the process of restenosis formation after PTCA. The common carotid arteries of atherosclerotic rabbits after PTCA were cultured in the artery organ-culture system and maintained in culture for 7 days. After 1d, 2d, 3d, 4d, 5d, 6d and 7d, MTT-test showed that the activity of vessels in the organ culture system unchanged. Pathology and histological technic were applied to check the intimal morphology especially the endothelial denudation and intimal hyperplasia. The concentration of chemical cytokines NO releasing in the process of restenosis were measured .The results showed the method of static organ culture could be successfully applied to keep the activity of culture arteries and study the process of restenosis formation after PTCA. The endothelial denudation and inflammatory cytokines releasing had intimately relationship with the restenosis after PTCA.

This study deals with improving the cytocompatibility of titanium by a coating with heparin(hep), collagen(col) and CD34 antibody. Collagen and heparin molecules were adsorbed onto a titanium surface using a layer-by-layer (LBL) self-assembly technique. The col/hep coating were formed by alternating deposition of negatively charged heparin and positively charged collagen based on electrostatic interactions. Finally the CD34 antibody was absorbed onto the surface of col/hep coating by electrostatic interactions. The chemical composition and surface topography were investigated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The fluorescence microscopy images proved that the CD34 antibody was existed on the surface of the col/hep coating. The SEM results and the MTT test results showed that, compared to the surface of col/hep coating and the surface of titanium, the CD34 surface had better endothelial progenitor cells (EPCs) attachment and proliferation. The EPCs on the CD34 surface displayed the morphology of flat endothelium, and a confluent cell layer after cultured for 2d. This study suggested that this method maybe have good potential for surface modification of cardiovascular devices.