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Al-5Zn-0.03In series alloys have been widely studied and used as sacrificial anode materials. Adding rare-earth (RE) element to Al-5Zn-0.03In sacrificial anode is the important way to improve its microstructure and properties. This paper focused on the effect of Er addition on the microstructure and properties of the Al-5Zn-0.03In-xEr alloy. Thermal analysis showed that the presence of Er in the series alloys reduced the solidification ranges and made their liquidus and solidus move to lower temperature. The microstructural analysis and hardness testing reveal that Er existed in the form of precipitation, refined the dendrites of the series alloys and improved the hardness of the series alloys. Investigation of the potentiodynamic polarization and the electrochemical impedance measurements were performed in 3.5 wt. % NaCl solution. The potentiodynamic polarization results indicated that the corrosion potential increased and the corrosion current density reduced with the increase of the Er addition. The Al-5Zn-0.03In alloy shows higher corrosion resistance with the increase of Er content. The EIS electrochemical impedance results showed that Al-5Zn-0.03In anode presented relatively uniform dissolution due to the refined microstructure by the addition of Er.

In this study, the assessment and calculation methods for the crack propagation life of steam turbine rotor shafts containing defects are presented. The analytic methods for estimating the average stress and the alternating stress amplitude of the steam turbine rotor shafts are introduced. The defects on/in the rotor shafts were regularized by the method of fracture mechanics, and the high cycle fatigue crack propagation life and low cycle fatigue crack propagation life of the rotor shafts are estimated from Paris formula. Taking the 60MW turbine rotor shafts containing an initial surface defect and an initial internal defect as the examples respectively, the crack propagation life of them were calculated. The results indicated that the assessment method for the crack propagation life can preliminarily be both used to estimate the safety-operating life and to analyze the fracture reason of a steam turbine rotor shaft containing defects. This paper can provide reference for periodic maintenance and safety evaluation of turbine rotor shafts.

In this paper, we study the electrowetting effect of superhydrophobic SU-8 film as the dielectric for Electrowetting-on-Dielectric (EWOD). The change of apparent contact angle (APCA) on superhydrophobic surface in electrowetting systems was measured and analyzed using a modified Lippmann-Yong equation. The variation of APCA between droplet and device surface under various DC voltage and AC voltage of different frequencies was fully experimented. The experimental results were in good agreement with the theoretical predictions. This study shows the potential of using superhydrophobic SU-8 film as the dielectric layer in high-performance EWOD devices.

In this paper, we study the electrical properties and breakdown phenomena of BaTiO3/Teflon composite ferroelectric thin film in electrowetting systems. The experimental results showed that the electrowetting effect and the breakdown voltage depend on DC voltage polarity, and this polarity dependence is closely related to the thickness of the ferroelectric film. Under AC voltages, the breakdown voltage increased directly with voltage frequency. These results are useful for designing reliable EWOD devices with low operation voltages and high robustness.

Experiment was performed to examine the plane polishing of SiC single crystal wafer by using the chemical magnetorheological finishing (CMRF) technique. The influence of some process parameters such as the concentration of diamond abrasive particles, the concentration of carbonyl iron powder and the machining gap in CMRF were studied comparing with the magnetorheological finishing (MRF) method. The results show that the surface roughness of polished SiC single crystal by the CMRF is slightly lower than that by the MRF. Polishing liquid with different components and processing parameters affects the coupling effect of mechanical removal and chemical removal in CMRF, and a better coupling effect can produce a better surface quality in CMRP. In the MRF, the surface roughness of SiC single crystal is lower for a higher concentration of carbonyl iron powder (CIP). However, in the CMRF, the CIP’s concentration may change the contact state between the catalyst and SiC, and the CIP’s concentration of about 20% can produce a better surface roughness of SiC. The machining gap between the polishing disk and the workpiece surface determines the processing effect, and the machining gap of 1.0 mm is suitable for the polishing of SiC in the MRF and CMRF.

Ratcheting deformation is studied on elbow pipe made of Z2CND18.12N by FEM software. The simulation is conducted by ANSYS. Chen-Jiao-Kim (CJK) kinematic hardening model is added in ANSYS for the study. The elbow pipe is subjected to internal pressure and reversed in-plane bending. Internal pressure can be constant or cyclic. Many different loading paths are used in the study. Ratcheting deformations of under different ways are studied. The result shows that ratcheting deformation occurs mainly in the circumferential direction. Ratcheting deformation at the crown and intrados of elbow pipe is more notable because of higher stress. Tensile or compressed load can influence the position of dangerous point. It is found that ratcheting deformations under different paths with same peak load are different.

The valve cover of a gray cast iron drain valve, used by a chemical company, cracked during its operation. The cracking reasons of the valve cover were investigated by fracture appearance observation of the valve cover, metallographic observation, SEM observation, chemical composition analysis of the corrosion products, finite element analysis of the valve cover by ABAQUS and tensile tests and impact tests of the cover sample at normal temperature and-12°C. After these investigation jobs, it can be concluded that there was no any significant cast defect or original defect in the fracture of the valve cover, the stress was much lower than the strength of valve cover material, and the cracking of the valve cover was caused by the expansion of the ice which was changed from the seeper between the valve cover and valve body when the weather temperature was lower than-12°C. At the end of this article, some proposals were put forward to the company in order to avoid similar accidents.

In this paper, the dielectric and electrowetting properties of Pb (Zr0.4Ti0.6)O3 (PZT) ferroelectric thin film are studied as the dielectric layer in electrowetting-on-dielectric (EWOD) device. The PZT thin film is formed by spin-coating, pyrolysis and annealing. The characterization results show that PZT thin film can serve as the dielectric of EWOD with a high dielectric constant and a great electrowetting performance when used in silicon oil bath environment. To test the electrowetting effect, a EWOD device with 200nm thick PZT ferroelectric thin film dielectric layer is fabricated. The variation of contact angle between droplet and device surface achieved with DC voltage, AC voltage and AC frequency change of electrowetting on PZT are fully experimented. The EWOD device with PZT dielectric layer can manipulate water droplet at low driving voltages. This study shows the potential of using ferroelectric ceramic material as the dielectric layer in high-performance EWOD devices.

The computerize numerical control (CNC) system is one of the key factors for the development of micro v-groove machine tools to fabrication micro v-groove structures. Based on the investigation on the machining of micro v-groove structures, a developed software contains five modules: editing, automatic programming, program control, manual control and human machine interface. A3200 software based motion controller integrated with the machine characteristics is used in this study to develop the motion control functions of the micro v-groove machine tool. Meanwhile, a method is proposed to redefine the instructions of M, T and S by setting monitoring points so as to enhance the scalability of CNC system. The results show that the CNC system software is not only stable and reliable, but also satisfies the basic requirements of the ultra-precision machining of micro v-groove structures.

This paper develops a three dimensional (3D) simulation system with QT platform and OpenGL 3D library by adopting the driver and Aerotech’s linear motor as hardware platform and INtime and A3200 controller as the software platform. The system uses numerical control (NC) code syntax checking module to test the NC code syntax and applies 3D simulation module to display the actual machining process. The interference and collision detection module is built in this system to detect the problem during the actual processing. The system therefore contributes to avoiding the trial and tests for the ultra-precision machining process and improving the machining efficiency as well as reducing the loss of ultra-precision components of machine tool due to the collision.

In an electrowetting-based liquid microactuator, two types of insulating materials are used for device operation: an dielectric material to provide capacitance between the liquid and conductor, and a hydrophobic coating at the interface of liquid and insulator. This paper investigates important physical properties for the insulating materials. Several alternative dielectric materials are compared for application in EW chips, breakdown phenomenon of insulating layers with different thicknesses is tested before and after droplet actuation. It appears that the used EW devices have lower breakdown voltages than unused devices, probably due to the locally trapped charges in the insulating layer.

The layered cylindrical shell is one of important structures of high pressure vessels. From 1977 to 2005 there were 8 urea synthesis reactors exploded. Seven of them were layered cylindrical shell structure. Therefore, there will be much more issues come out and waiting for us to study and explore. In this paper, we take the urea synthesis reactor exploded in 2005 in China as an example to study why and how a multi-layered exploded. Through the research work, we not only concluded why and how a multilayered vessel exploded but also established a method to analyze the serious explosion accident of complex vessels such as urea synthesis reactors.

This paper introduced the development of marine on-shore power supply system in China and abroad, and described the different control strategy of shore power based on uninterruptable power on-shore connection, as well as instance of variable frequency power supply between the port and ship for controlling harmonicdistortion, based on the Matlab simulation software to establish the simulation model of active power filter system,so as to provide the guarantee for achieving reliable paralleling between shore power and marine electrical system with effective harmonic elimination.

Typical combustible particle coal has been analyzed by using turbulence-chemistry interaction models to realize which models are more accurate and reasonable on pulverized coal MILD combustion. Three turbulence-chemistry interaction models are examined: the Equilibrium Mixture Fraction/PDF (PDF), the Eddy Break Up (EBU), the Eddy Dissipation Concept (EDC). All of three models can give a suitable prediction of axial velocity on combustible particle coal MILD combustion because turbulence-chemistry interaction models have little influence on flow field and flow structure. The Eddy Dissipation Concept model (EDC), based on advanced turbulence-chemistry interaction with global and detailed kinetic mechanisms can produce satisfactory results on chemical and fluid dynamic behavior of combustible particle coal MILD combustion, especially on temperature and species concentrations.

The digital frequency meter was a device to detect and display the frequency. In many design complexity, features a variety of electronic devices, the digital frequency meter was one of the essential equipment. It was widely used in various fields. The core of the frequency meter is AT89C51 microcontroller. It used SCM counting and timing functions to achieve the measurement pulse within a certain gate time, and it uses LED digital display tube displays the measured frequency. The device has a high frequency accuracy measurement, real time, and it has a simple, easy to carry, strong expansion capability, a wide range.

The precursor thienyl-group-bearing acrylic polymer (TE-PAA-co-PMMA), obtained with 3-Ethyl acrylate-thiophene (TE-AA) and methyl methacrylate through free radical polymerization, was prepared electrochemically to free-standing, processible and conducting conjugated PTE-PAA-co-PMMA film by direct anodic oxidation in CH2Cl2 containing 50% boron trifluoride diethyl etherate (BFEE). The structure, electrochemical, optical, thermal properties and morphology of as-formed electropolymer were systematically investigated by FT-IR, cyclic voltammetry, UV-vis, thermogravimetry and scanning electron microscopy. Cyclic voltammetry studies demonstrated that the precursor can be reversibly oxidized and reduced accompanied by obvious color changes from dark blue to transmissive yellow-green and the electropolymer has good redox activity as well as excellent electrochemical stability. Additionally, fluorescence spectra show that the so-obtained crosslinked polymer is still good blue-light emitter.

An efficient Single Source Single Relay Cooperative Automatic Repeat Request (CARQ) protocol for TDMA-based High Delay Wireless Networks is proposed in this paper, which enables both of the Source and the Relay to retransmit packets to the Destination based on the special nature of TDMA-based time frame structure, and increases the successful transmission probability of a packet from the Source to the Delay using the high delay between the Source and the Relay.. By means of comparison of the system throughput between the two ARQ algorithms (the traditional and the proposed algorithms), we proved that the proposed protocol gave a better performance in poor channel conditions.

A porous poly (5-cyanoindole) film was easily electrodeposited and for the first time evaluated as an active electrode material in 1.0 M H2SO4. The poly (5-cyanoindole) film was investigated using scanning electron microscope, cyclic voltammetry, impedance spectroscopy and charge-discharge test. The specific capacitance of poly (5-cyanoindole) electrode was 336 F g-1 under the current density of 2.4 A g-1 and decreased by 30% after 1000 cycles, which indicated that poly (5-cyanoindole) electrode had good cycle stability. Additionally, the specific energy of poly (5-cyanoindole) electrode reached 23 Wh kg-1 when the specific power was 190 W kg-1. These results indicated the feasibility of poly (5-cyanoindole) as electrode material for supercapacitors.

Aimed at achieving a high speed and precision circumferential positioning of pipe under low energy consumption, a paralleling hydraulic control of variable frequency motor and valve (PHC-VFMV) system is designed for the swing mechanism of segment erector. Firstly, with a view to the working principle of the swing mechanism, a hydraulic circuit of the PHC-VFMV is designed. Then, two sub-circuits of the hydraulic circuit are separately modeled and equipped with suitable controllers. Finally, one valve control (VC) system and the designed PHC-VFMV system are tested in AMEsim platform. Results show that, while guaranteeing a good performance of speed and accuracy, the PHC-VFMV could achieve a better performance in energy saving than VC.

Obtaining narrower kerf and smaller heat affected zone (HAZ) is a difficulty in laser cutting carbon fiber reinforced plastic (CFRP) composites. In order to solve this problem, the experiments used a semiconductor UV laser to cut CFRP have been done and how laser parameters (include pulse power, repetition frequency, cutting speed and direction) influent the width and HAZ of kerf have been achieved. In the meantime, compared with infrared laser cutting CFRP, the quality of CFRP cut by different wavelength laser has been investigated. The results show that owing to CFRP has the characteristic of anisotropy, laser cutting direction is the most significant factor that affects the quality of kerf cut by UV laser. The study also found that owing to high single photon energy, the narrower kerf and smaller HAZ around kerf can be get by UV laser cutting CFRP, nevertheless, it can’t be achieved by infrared laser cutting CFRP.

The particle concentration distribution in the foundry is very important not only for the occupational health of foundry workers but also for creating green foundry industry. In this study, the authors measured the particle concentration distribution in a foundry workshop, and analysis the characteristics of foundry dust pollution with the consideration of total dust control in the recent foundry industry. The results show that the concentrations of PM10 and PM2.5 are high in the central and low in the ends of the workshop. It is about 54% of all test sites with higher concentration of PM10 and PM2.5 than the limit values of national standards. However, the PM4 concentrations of about 31% test sites are higher than limit of national standards. It is obviously that sandfilling process, cavity repair and sweeping in mold making process can produce a lot of dust. This study may provide guidance for the foundry pollution control engineering and workshop operation management system.

Combination of disinfection method gives advantages. In this work, inactivation of E. coli using ZnO nanofluids and ultrasound is evaluated. Growth curves of bacteria were investigated to reveal the inactivation activities of ZnO nanofluids and ultrasound. The effects of combination of ZnO nanofluids and ultrasound, ultrasound time, ultrasound induction point and the induction order of ZnO nanofluids and ultrasound were studied. The results suggested that combination of ZnO nanofluids and ultrasound gives better inactivation effect on E. coli when comparing with single disinfection method. Ultrasound for 10 s helped ZnO nanofluids inhibiting bacteria better than ultrasound for 30 s /60 s. Ultrasound induction point (at 0 hr, 2 hr or 4hr) did not affect on ZnO nanofluids to exhibit the inhibiting property. Induction ultrasound prior to adding ZnO nanofluids showed the better inactivation effect on E. coli. The results also displayed that in this work, ultrasound was mainly worked as a pre-treatment step, instead of a disinfection method.

Joints and fissures have a strong impact on the stability of engineering rock mass. In this paper, a self-improved analysis program of FLAC3D is adopted to study problems in fluid-solid coupling field. Then, by simulating the excavation process of a slope under the effect of fissure water pressure, the crack initiation and propagation in engineering rock mass reappears. Besides, the numerical simulation results are decent and effective, which can provide some references for engineering application.

In order to realize high speed, high precision, high reliability, miniaturization performance of the CNC (Computer numerical control) system, this paper proposed a hardware platform of embedded CNC system based on OMAPL138 and FPGA. OMAPL138 is a SOC using C6748 DSP kernel and ARM9 kernel dual-core structure, the kernel frequency can achieve up to 375/456 MHz. ARM kernel of the CNC system which runs the Linux operation system is responsible for task management, DSP kernel is in charge of real-time interpolation and look-ahead algorithm, and FPGA module generates pulses to control the movement of the servo motor. Firstly, the overall hardware architecture of the embedded CNC system was designed. Meanwhile the hardware circuit design of CPU core module based on OMAPL138, human-computer interaction module, EMIFA bus interface of the FPGA core module were emphasized in detail, and also the serial port, Ethernet, USB communication interface module were introduced. A serial test experiments have been conducted and the results have shown that this embedded CNC system is powerful and stable.

The V-groove component which needs to be machined by ultra-precision CNC (Computer numerical control) machine tool is a core part in optical fiber connector. A design of keyboard module for V-groove ultra-precision CNC system based on LPC1343 is presented. This paper introduced the functions and features of LPC1343 and described the overall hardware structure of the keyboard module at first. Then the basic design, such as scan and decoding, design principle of module circuit and communication process between keyboard module and upper computer, were emphasized in detail. Afterwards, the functional design including data editing, LED indicator driving, override switch adjusting and motion control operating were also finished. A series of test have been conducted and the results have shown that this kind of keyboard module is reliable and stable.

In order to research the self-centering capacity of prefabricated frame joints, this paper designed analysis models of prefabricated frame joint with the finite element software ABAQUS, contrastively analyzed seismic behavior of joint applied pretention and joint without pretention. Joint applied pretention is found to have better self-centering capacity. Then the paper calculated and analyzed the factors of stretching control stress, number of post-tensioned steel. The results show that number of post-tensioned steel has a greater influence on the seismic behavior of the structure, and the stretching control stress has influence in a certain range. The results have some degree of guiding significance for the popularization of prefabricated frame.

In order to solve the problem that delamination and bur will be easily produced in the process of the carbon fiber reinforced plastic (CFRP) composites, the cutting experiment of CFRP machined by pulsed Nd:YAG laser has been carried out. In the meantime, this paper investigates the mechanism of interaction between infrared laser and CFRP composite material and the quality of kerf influenced by different laser parameters and cutting directions. The study found that choosing appropriate laser parameters and cutting direction are effective means to get smaller heat affected zone (HAZ). This paper analysis the cross section morphology of kerf .The results show that the cross section does not appear stratified phenomenon and the surface is smooth, so the feasibility that infrared laser can be used to cut CFRP composites is verified.

To guarantee the QoS of the various traffics and take good advantage of the network resource, the QoS routing protocol based on resource optimization is proposed. By the network state information dynamic update and the QoS routing optimization model design, the QoS routing protocol can provide the optimal path for real-time traffic, broadband traffic and best effort traffic in time with low control message cost. Simulation shown that, compared to the traditional shortest path routing, the QoS routing can satisfy the demand of traffics and can improve the network performance.

We have designed a high resolution and dule-path optical turbidimeter. The right angle scatted light turbidimeter is mainly for water in low turbidity levels, especially for drinking water. Mechanical design of the optoelectronic receiving room and the realizing circuit for modulation and demodulation are described in detail. To achieve good linearity in the measuring range from 0 to 5 NTU, pulse width modulation (PWM) and demodulation techniques are proposed, in this way, low temperature-drift and good anti-jamming ability can be obtained without the interference of background light. To improve the precision, the ratio algorithm which measures the ratio of the scattered light and reflected light is introduced in a dule-path optical system so that the interference of light emission can be eliminated effectively. Through the analysis and comparison of the experimental results, the linearity is improved by the ratio algorithm with a correlation coefficient for about 0.99932.

The purpose of this experiment is to evaluate the nutritional value of amino acids and its commercial value in the fish processing sector in Antarctic krill with cross-referenced in the white shrimp. For determination of the composition of 17 amino acids in the two shrimp muscle, free amino acids were measured using sulfosalicylic acid method, hydrolysed amino acid using hydrochloric acid hydrolysis.17 kinds of hydrolysed amino acids are measured in the muscle of Antarctic krill and White shrimp, which total content is 513.59±18.56mg/g and 537.61±16.8mg/g respectively.16 kinds of free amino acids are measured, which total content is 616.88±44.61mg/100g and 1276±75.67mg/100g respectively, while cysteine is not found. According to amino acid score (AAS), chemical score (CS), the limiting amino acid of Antarctic krill and White shrimp is valine and methionine + cysteine. The umani amino acids accounted for 27.76% of free amino acids and 35.69% of hydrolysed amino acids in Antarctic krill, while White shrimp is 41.08% and 31.52% respectively. The amino acids in Antarctic krill, TAV of which is greater than 1, include glutamic acid, alanine, lysine and arginine.

The research investigates various methods to identify magnesium oxide influences on the crystal structure and hydration properties of tricalcium silicate. The f-CaO content of the clinkers were analyzed by chemical analysis. The complex disordered superstructure of the tricalcium silicate has been studied by a joint XRD, NMR and TEM. The results show that MgO exerts a remarkable influence on the polymorphisms of C3S. Mg is not only substitutional atom but also interstitial atom in the crystal lattice of tricalcium silicate. The HRTEM pattern of C3S doped with MgO is covered by the various irregular lattice. The addition of appropriate amount of MgO in raw meal can change the formation kinetic of C3S, slightly perturb the environment of SiO44- tetrahedral, modify the crystal structure of C3S and affect the hydration activity. Doped with MgO in the raw meal can slow down the hydration rate of alite slightly in early stage.

The flue gas simultaneous desulfurization and denitrification was studied for its feasibility with the new gas-liquid medium by using Ca(OH)2 as absorbent. The effects on key operating parameters were analyzed. They are pH, inlet temperature of flue gas and inlet concentration of air pollution. When pH is almost 5.5-6, and inlet temperature of flue gas is between 110℃ and 120℃, the results show that the removal efficiency of SO2 and NO are above 85% and 80% using rotating biological technology (RDB), respectively, which can satisfy most requirements of industrial scale applications. Besides, When CSO2 is more than 1500 (mg/m3), with the rising of imported pollutant concentration, desulfurization efficiency continues to increasing and denitrification efficiency was growing slowly.

Four novel cross-linked network conjugated poly (methacrylic acid) functionalized poly (9-aminofluorene) films were prepared by a precursor polymer approach, i.e., poly { poly [ N - (9H-fluoren-9-yl) methacrylamide ] } (P1), poly { poly [ N - (9H-fluoren-9-yl) methacrylamide-co-methacrylic acid ] } (P3), poly { poly [ N - (9H-fluoren-9-yl) methacrylamide] -co-9-aminofluorene } (P2) and poly { poly [ N - (9H-fluoren-9-yl) methacrylamide-co-methacrylic acid ] -co-9-aminofluorene } (P4). As-prepared polymer films had good redox activity and structure stability in concentrated sulfuric acid. Fluorescence spectra indicated that the soluble cross-linked polymers were good blue light emitters and in solid state they were blue-green light emitters.

Novel poly (selenophene-co-3-methylthiophene) was successfully achieved by directly electrochemical oxidation of the monomer mixtures of selenophene and 3-methylthiophene (3MeT) in boron trifluoride diethyl etherate. The effect of monomer concentration ratios on the copolymerization were investigated by cyclic voltammetry. The structures of as-prepared copolymers were characterized by UV-vis and infrared spectroscopy. The conductivity and thermoelectric measurements revealed the incorporation of 3MeT into the polyselenophene (PSe) chain improved significantly the conductivity and thermoelectric property of PSe.

The deformation and tension of textile between two dyeing roller during supercritical fluid spray dyeing was studied in this paper. The parameter equations were built by introduced the transformation parameter based on the mechanical equilibrium of infinitesimal element at the premise of considering the elasticity of textile. The results show that the internal stress of textile is far less than the tensile strength of the fabric, and the operating parameters of supercritical fluids spray dyeing has obvious effect on the deformation of textile. The simulating analysis may provide a theoretical basis and guidance for the actual process of supercritical fluid spray dyeing.

Rheological and interfacial property of nanoAl with Hydroxyl-terminated polybutadiene (HTPB), glycidyl azide polymer (GAP) and poly (ethyleneoxide-co-tetrafuran)(PET) were investigated by means of RS-300 rheometer, DCAT21 dynamic contact angle measuring instrument, interface surface tension meter (Germany) and X-ray photoelectron spectroscopy (xps). Rheological properties of three binders and nanoAl/binder suspensions in the mixing ratio of 1:2 were discussed. Results show that Three kinds of binders exhibit pseudoplastic characteristics with the apparent viscosity of less than 3 Pa s,and have weak interaction between molecular chain segment of itself. Within 30~60°C, with temperature increasing, the apparent viscosity of nanoAl suspensions decreases, in which the nanoAl/HTPB and nanoAl/GAP belong to pseudoplastic fluid of sensitive to temperature, with flow activation energy of 38.05 kJ/mol and 52.07 kJ /mol, respectively, but nanoAl/PET belongs to a bingham fluid of sensitive to changes in the shear rate, with flow activation energy of only 1.506 kJ/mol. The contact angles of nanoAl,GAP,HTPB and PET were measured by means of dynamic contact angle/surface tension instrument. The calculated values of adhesion and spread coefficient of nanoAl with binders decrease in the order Wnano-Al/PET>Wnano-Al/GAP>Wnano-Al/HTPB and Snano-Al/PET>Snano-Al/GAP>Snano-Al/HTPB.The results indicate that the interactions of nanoAl with binders decrease in the order nanoAl/PET>nanoAl/GAP>nanoAl/HTPB,which is consistent with the trends of apparent viscosity of the suspensions . Binding energy of Oxygen in nanoAl/HTPB is 532.03 ev,which is bigger than that of nanoAl,and indicate a strong action between nanoAl and HTPB.

This paper develops a discretization algorithm for non-uniform rational B-spline (NURBS) curves. The algorithm is used for CAM software which is developed for HNC-3000 five-axis woodworking NC milling machine. Functions from the CAM software divide the NURBS into dense segments with equal arc length by vertex set p1, p2pn. The algorithm simultaneously considers chord error δ and curvature of the NURBS curve to maximize the arc length of the segments to get vertex set p'1, p'2 pm'. The algorithm can be described as f (p1, p2pn, δ) = (p1', p2'pm'). The complexity of the algorithm is O (n).

It is necessary to study the stability and robustness of the anti-locked braking system (ABS) of vehicles because there are parameter perturbations and un-modeled dynamic features in the system. On the basis of the ABS model and the mixed sensitivity method, a robust control strategy for ABS is put forward and the H robust controller is designed in this paper. The simulation of the process of ABS shows that the robust control system can keep stable and is effective on decreasing the undesirable influence of the fluctuation of parameter such as load, brake performance coefficient and road condition. Furthermore, the tire slip ratio can be effectively controlled around the desired value, and the braking performance can be obviously improved.

We report here experimental data for transmission of electromagnetic waves through a variety of softmaterial structures made of plastic tubes and ionic solutions, as compared to that in the free space. The results firmly support the theory on softmaterial waveguides in the environment of ionic solutions. This is a solid step towards a better understanding of the underlying physics for the electrical communication in biosystems through axons and membranes. It also offers valuable insight for further experiments with artificial materials at the nanoscale, and experiments in live animals.

A novel synthesis route for a MCM-41 structure with Y zeolite seeds colloidal has been developed. The route is different from conversational method of highly ordered MCM-41 assembled from Y zeolite seed colloidal. The material was characterized by various techniques. The results indicate that the material has well-ordered hexagonal structure, with a thicker wall than that of the sample synthesized by a direct hydrothermal route (N-MCM-41). Furthermore, it has a stronger acidity. The sample was used as the support of a Pd-Pt catalyst for the polyaromatics hydrogenation. It was demonstrated that the introduction of building units of Y zeolite enhances the activity of polyaromatics hydrogenation. It can be concluded that the pore structure and acidity of support is a key factor for the design of a sulfur-resistant noble metal catalyst for aromatics saturation of diesel.

Performance boosting of modern computing systems is constrained by the chip/circuit power dissipation. Dynamic voltage scaling (DVS) has been applied for reducing the energy consumption by dynamically changing the supply voltage. One can apply an adaptive scheme by computing a threshold speed of the supplied voltage, and adopting greedy online DVS scheduling algorithm when the voltage exceeds the threshold while choosing a conservative speed on the contrary. This paper presents an algorithm to determine the threshold speed. The proposed algorithm allows to obtaining the threshold speed for the adaptive DVS scheduling algorithm more efficiently.

Intensive study on flowing properties of two-phase fluid of gas and liquid during pipeline pigging helps to improve the safety operation of rich gas pipeline. Therefore, based on the multiphase fluid transient simulation software, a two-fluid model is employed to study the flowing regulation of gas and liquid in practical operation of natural gas pipeline pigging,especially the change rule of velocity,flow pattern, pressure, liquid holdup ratio, and liquid slug in the passing ball process. The results reveal that three flow patterns appeared in pipeline pigging. They are stratified flow, slug flow and bubble flow. The place where the particular flow pattern appears is related to the terrain. The biggest pressure is found at the entrance, then pressure comes down along the pipeline, and fluctuate according to the fluid amount and terrain; the transient velocity of pig is coherent with the terrain and liquid holdup ratio; small slug flows are easy to gather and form into a longer one. The research can somehow guide to the safety operation of natural gas pipeline pigging.

The electrochemical properties of hard carbon (HC) have been investigated for use as negative electrode for lithium ion capacitors. The HC electrode was characterized by scanning electron microscope (SEM) method. The HC negative electrode was galvanostatically prelithiated at 0.1C for three cycles between 0.05-2 V. The LIC with activated carbon and HC electrodes was characterized by cyclic voltammetric analysis at the scan rate of 0.1 mV s-1 with different voltage ranges. The rate capability of the LIC was tested up to 100C and the retention is 54 %. The cycle performance is retained up to 86% at 50C and 80% at 100C even after 10,000 cycles. The results indicate that hard carbon is suitable as negative electrode materials for high power energy applications.

Hydrothermally stable mesoporous aluminosilicates with tubular morphology and hexagonal nanochannels were prepared by a new route. The route is different from conversational method of highly ordered MCM-41 assembled from Beta zeolite seed colloidal. The synthesis of Beta zeolite-like seeds is a novel route of acid treatment. The XRD results indicated that the synthesized materials were well-ordered hexagonal mesostructures of MCM-41. The highly regular hexagonal mesostructures could survive by steaming at 750 °C for 2 h, exhibiting good hydrothermal stability. Combining the SEM investigation, the as-made materials showed tubular morphology with diameter of 0.4 μm. The sample has a stronger acid strength, and was used as the support of a Pd-Pt catalyst for the polyaromatics hydrogenation. It has high activity and good sulfur tolerance towards hydrogenation of aromatics of smaller diameter. It was demonstrated that the introduction of building units of Beta zeolite enhances the activity of polyaromatics hydrogenation. It can be concluded that the pore structure and acidity of support is a key factor for the design of a sulfur tolerant noble metal catalyst for aromatics saturation of diesel.

To improve the overall performance of the domestic high-modulus carbon fiber/cyanate composites, a macromolecular coupling agent (SCC) based on the raw material styrene, methyl acrylate and γ-methyl (acryloyl) trimethoxysilane was synthesized. It also studies the effect of coupling agent content on the mechanical properties of composites. The results show that the dosage of macromolecular coupling agent with 3%, the performance of the composite materials has been notable improved, its bend strength and interlaminar shear strength are 1100Mpa and 63.5Mpa, which has been raised 6.0% and 16.1%, respectively. SEM micrographs show that the addition of a coupling agent effectively improve the interface compatibility between the resin and fibers in composite.

Longitudinal ultrasonic wave signals, transverse ultrasonic wave signals and other ultrasonic body wave signals generated by partial discharge are analyzed emphatically in the acoustic emission method of partial discharge detection in high voltage equipment [1-. Velocity of longitudinal ultrasonic wave is often used to calculate partial discharge defects position in the location study of partial discharge. In practical applications errors are always large. And a recent study finds that a class of plate ultrasonic guided waves will be inspired when ultrasonic body waves are transmitted from the gaseous medium to the metal medium [9-1. As the attenuation coefficient is small and the transmission distance is large when the waves propagate along the metal plate, in the partial discharge detection, ultrasonic signals detected by the ultrasonic sensor attached to the equipment enclosure include ultrasonic guided waves besides the ultrasonic body waves.

PurposeTo analyze the biomechanics of cervical spine after one-and two-level Total Disc Replacement (TDR) and two-level Anterior Cervical Discectomy and Fusion (ACDF).MethodsSeven adult human cadaveric cervical spines were biomechanically evaluated under eccentric displacement control in six mechanical modes, including flexion (Flex), extension (Ext), left bending (LB), right rending (RB), left rotation (LR) and right rotation (RR).ResultsIn fusion-treated specimens, range of motion (ROM) at instrumented level decreased as much as 81.78%, and other levels also demonstrated big difference in ROM. In arthroplasty-treated specimens, ROM showed little difference from that of the intact state. Large motion variation happened in LB, RB and Ext after both fusion and nonfusion surgical treatments.ConclusionsTDR had a more reasonable motion sharing than ACDF, especially in Flex, Ext, LR and RR. No evident influence of motion change was observed after adding an extra level of TDR.