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Perforated structure is the mechanical weak link of polymer-bonded explosive (PBX). Improving its mechanical property may promote the reliability and effectiveness of weapon system. In this study, strengthening of the perforated PBX plate is conducted by employing surface coating. Digital image correlation (DIC) analysis results suggest that the regional applied epoxy coating layer is able to improve the mechanical properties of the plate. By confining the deformation and releasing the stress concentration around the perforation, the coating layer enhances the load carrying ability and energy dissipation capacity of the plate significantly. This investigation may provide a convenient and effective structure modification method for energetic material, and at the same time, lay foundation to the performance optimization of weapon system.

In order to study the effect of spray distance on the structure and high temperature oxidation resistance of feather-columnar thermal barrier coatings, the feather-columnar ZrO2-7wt. % Y2O3 (7YSZ) thermal barrier coatings were prepared at spray distances of 650 mm, 950 mm, 1100 mm, 1250 mm, and 1400 mm by plasma spray-physical vapor deposition (PS-PVD) technology. The surface roughness, micro morphology, and porosity of the sprayed 7YSZ coating were analyzed by 3D surface profiler, SEM, XRD, etc., and the impedance spectrum characteristics of the 7YSZ coating were characterized by electrochemical alternating current (AC) impedance technology. In addition, the high temperature oxidation resistance test of 7YSZ coating under different spray distances was carried out at a temperature of 1000 °C to study the influence of spray distance on the high temperature oxidation resistance of 7YSZ coating. The research results show that the surface roughness and porosity of feather-columnar 7YSZ coating increased sequentially with the increase of spray distance. At the same time, The YSZ grain boundary resistance value increased exponentially as the porosity of the coating increases. Where the spray distance was in the range of 650 mm and 1250 mm, the high temperature oxidation rate constant of the coating increased with the spray distance. However, the spray distance was greater than 1250 mm, and the spray distance had no significant effect on the high temperature oxidation resistance of the coating.

The compression behavior and mechanical properties of the Mg-13Gd-4Y-2Zn-0.5Zr (wt.%) alloy filled with intragranular long-period stacking ordered (LPSO) phases at different temperatures were investigated. The results showed that the higher the compression temperature, the smaller the plastic strain that the grains withstand. The grains changed from equiaxed to flat strips when compressed at 350°C, and the morphology of the grains did not change at 450°C. Due to the existence of DRX grains, compression at 450 °C didn’t cause large-angle kink, but the kink angle at 350°C was very large. DRX grains only appeared at the grain boundaries and around the intergranular LPSO phase at the beginning of compression, and only appear at the kink bands (KBs) after the lamellar LPSO phases begin to kink. DRX grains gradually increased with the KBs increasing.

The homogenized Mg-10.37Gd-3.66Y-2.27Zn-0.52Zr alloy was subjected to multi-passes reciprocating upsetting extrusion (RUE) deformation with variable temperature. The microstructure evolution and mechanical properties of as-homogenized and RUEed samples were investigated. The results showed that the area fraction of DRX grains gradually increased via the continuous consumption of coarse grains containing lamellar LPSO, and the content of the bulk LPSO phases gradually decreased due to continuous fragmentation. After three passes deformation, the microstructure was almost composed of completely DRXed grains. The LPSO phases with different morphologies were coordinated deformation by kinking, tearing, etc during RUE process. It is worth noting that after four passes, the lamellar LPSO phase did not disappear, but mixed with the fine DRXed grains together. In addition, a mass of particles were produced after each low temperature deformation, indicating that reducing the deformation temperature is beneficial to the dynamic precipitation. The yield tensile strength (TYS), Ultimate tensile strength (UTS) and fracture elongation (FE) of four passes deformed alloy reached 372.6 MPa, 320.8 MPa, 8.1%, respectively. The improvement of mechanical properties is attributed to the two main strengthening mechanisms: grain refinement and LPSO strengthening.

Morphology of dispersoids in an annealed Al-Mg alloy were investigated using TEM. Five kinds of dispersoids with different structures and morphologies were observed in an annealed Al-Mg alloy. The 1st, or spherical-like one is monoclinic structured θ-Al45(Mn,Cr)7 phase with twin and orientation domain. The 2nd or plate-shaped one is η-Al5(Mn,Cr) phase with monoclinic or pesuo-tetragonal structure. The 3rd or prismatic-like one is a new hexagonal structured Al6.4Mn phase with a unit cell of a=1.72nm, c=1.27nm, and γ=120°, and the 4th or big rod-shaped one is orthorhombic structured Al6(Mn,Fe) phase which is often reported. The 5th one is E-Al18Mg3(Mn–Cr)2 phase with twin or triple twin observed occasionally in Al-Mg annealed alloy. The first two of dispersoids are in majority, followed by the middle two and a small number of the fifth. Formation mechanisms of these particles in Al-Mg alloy are discussed according to phase diagram and possible formation of the twins in the particles are described based on minimum energy.

In this work, feather-column 7YSZ thermal barrier coatings (TBCs) were prepared by plasma spray-physical vapor deposition (PS-PVD). The anti-particle erosion test was carried out at room temperature to study the erosion behavior and failure mechanism of PS-PVD TBCs. The results showed that the particle erosion process of the PS-PVD TBCs experienced three stages of high-rate, medium-rate and slow-rate erosion. In order to improve the particle erosion resistance of the PS-PVD TBCs, different thicknesses of dense-layered coatings were prepared on the surface of the PS-PVD TBCs by air plasma spraying (APS). The effect of dense-layered thickness on the erosion behaviour of PS-PVD TBCs was discussed. Experimental results showed that, as the thickness of the dense-layered increased, the erosion resistance of the PS-PVD TBCs enhanced. When the thickness of the dense-layered coating was 5μm, it was not obvious upon the influence on the erosion failure behavior of the PS-PVD TBCs. In the case of a 10μm dense-layered coating, the erosion resistance performance of the PS-PVD TBCs improved by about 30%. While the erosion resistance performance of the PS-PVD TBCs increased almost 4 times when the thickness of the dense layer reached 20μm.

In this study, (Ti0.5Ni0.5)80Cu20 metallic glass composites sample with 3mm diameter were prepared by levitation suspend melting-water cooled Cu mold process. Microstructure and thermodynamic behavior of the alloy were characterized by XRD, OM and DSC. the potention dynamic polarization curves in artificial seawater were tested by electrochemical workstation in a three-electrode system. The results showed that the as-cast microstructure of the alloy is consist of supercooled austenite phase, thermally-induced martensite phase and amorphous phase. Due to cooling rate, random dense pile of amorphous structure formed in surface of the alloy and supercooled austenite phase formed in interior. Besides, the alloy also presented excellent corrosion-resistance in artificial seawater for its higher corrosion potential (Ecorr) and polarization resistance (Rp), lower corrosion current density (Icorr) compared with Ti-6Al-4V(TC4) alloy.

In this paper, the anticorrosive properties of perfluorooctanoic acid (PFOA) on Q235 mild steel corrosion were estimated in simulated seawater. XRD and EDS results showed that PFOA could penetrate the rust layer and adsorb on the surface of steel and destroy rust layer. Our polarization measurements revealed that PFOA is a useful inhibitor, with a more pronounced anode effect, while impedance results also indicated successful adsorption of the PFOA species on the steel surface. Laser confocal scanning microscope studies give the evidence that corrosion resistance of the treated samples improved compared to the untreated samples. Molecular simulation technique was used to confirm the ability of PFOA to decrease corrosion. The 150 g/L concentration of PFOA showed the most significant improvement in the anticorrosive property.

Reed Pulp was Raw Material that Pretreated by Four Methods {ultrasonic, Microwave, N, N-Dimethyl Acetamide (DMAc) and Tetrahydrofuran (THF)}. Reed Microcrystalline Cellulose (MCC) was Prepared by the Dilute Hydrochloric Acid Hydrolysis from Pretreated Reed Pulp. the Influences of Pretreatment Methods on Crystalline Type, Crystallinity and Crystallite Size of MCC were Investigated by X-Ray Diffraction (XRD). the Results Showed that the Crystallinity of MCC with Four Pretreatment Methods was 68.45%, 62.28%, 63.21% and 69.56%, Respectively. the Average Crystallite Size of MCC Prepared by Hydrolysis after Pretreated by Dmac was the Largest. whereas, the Crystal Type of MCC was Not Changed, it was still the Cellulose Type I. Comprehensive Analysis Indicated that the Effects of MCC Prepared by Hydrolysis after Pretreated by Ultrasonic were the Best.

An improved grey wolf optimization (IGWO) algorithm is proposed for solving constrained mechanical design problems in this paper. In proposed IGWO algorithm, a novel nonlinearly update equation of convergence factor based on sines function is presented to balance the exploration ability and exploitation ability. The feasibility-based rules based on tournament selection was introduced to handle constrains. Simulation results and comparisons with other state-of-the-art algorithms using three constrained mechanical design problems are provided.

The aim of this paper is to present a 3D tolerance mathematical model for complex feature geometric variations oriented the new generation Geometrical Product Specifications (GPS). According to the definition of geometric feature and taxonomy of geometric variations in the new generation GPS system, the proposed model is based on the small displacements torsor (SDT) concept, and the geometric deviations treated as relative location or rotation variations between the nominal geometry feature and the associated feature are expressed by the SDT parameters. Moreover, the tolerance models for several kinds of complex feature geometric variations are constructed and discussed. Finally, a numerical example is given to illustrate the application of the proposed tolerance model, and the results indicate that the proposed model is capable in dimensional and geometrical tolerances modeling. The model completely based on the mathematics foundation is in compliance with the current GPS standards system.

Aiming at the traditional measurement methods and equipment cannot meet the accurate measurement problems of complex inner surface geometry parameters. This paper proposes combining the laser displacement sensors, rotary encoders and machine control system to build the measurement system. This system overcomes the traditional contact measurement of the low efficiency, low velocity, low accuracy, and realizes measuring slender and long inner surface. Through analysis and processing of the acquisition of point cloud data, draw a cross-sectional contour of the workpiece to achieve a precise measurement of the internal surface.

7072Al is widely used as cladding layer for heat-transfer components. In this paper, the microstructure, mechanical properties and electrochemical properties of simulated-brazing 7072Al alloy with Zn addition were investigated. Transmission electron microscopy (TEM) observations revealed that, in the simulated-brazing state, Zn-addition could promote the precipitation in the 7072Al alloy. Tensile testing results indicated that, in comparison with 7072Al alloy, the mechanical properties were improved after Zn-addition. Electrochemical testing results revealed that the simulated-brazing alloy showed a negative shift of the corrosion potential with the addition of Zn element.

Graphene, with outstanding mechanical properties of 1TPa of Young’s modulus and 130GPa of tensile strength, has been considered as an excellent reinforcement in composites. Graphene nanoplates (GNP) reinforced Al5083 alloy composites were successfully fabricated by powder metallurgy method. Flake-like Al5083 powder was firstly added into a GNP-alcohol solution and then dried in vacuum oven at 343 K for 5 h. The composite powders were sintered at 723K under pressure of 300 MPa for 1 h, followed by extrusion at 623 K. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed for microstructure characterization. Al4C3 cannot be observed in the composite, suggesting that there was no reaction occurred between GNP and Al matrix during the processing. Tensile test results revealed that the ultimate tensile strength and tensile elongation of 0.3wt.%GNP/Al5083 composites were 580MPa and 15%, respectively, showing optimal combination of strength and ductility. The relevant strengthening mechanisms of the composites were discussed.

Two-stage aging treatments were applied to Al-6Si-2Cu-0.5Mg casting alloy, and the influence of aging treatment parameters on the microstructure and mechanical properties was investigated. The experimental results indicated that the microstructure and mechanical properties of Al-6Si-2Cu-0.5Mg alloy were significantly influenced by the aging time and temperature, and the elongation remarkably increased with the aging time increasing before 7 h. In the case of the alloy aged at 200°Cfor 2h, higher hardness and tensile strength were obtained, which may be attributed to precipitation of a large amount of Cu-rich phases. However, the higher elongation was achieved in the alloy under 200°C aging treatment for 5h, while its hardness and tensile strength slightly decreased. It is mainly due to the amount of the Cu-rich phases decrease slightly, but the morphology of the phases evolved from plate-like to bulk-like structure.

The influences of spinning deformation and heat treatment on microstructure and tensile properties of A356 alloy at different cooling rates were investigated in this study by optical and scanning electron microscopes. The results indicated that spinning deformation enhanced the tensile properties of the alloy due to the reduction of Si size and porosity percentage, especially in the samples with coarse microstructure. Heat treatment increased the strength while decreased the ductility of the alloy because of the precipitation of brittle Mg2Si in Al matrix. It is suggested that the spinning deformation processing is an effective technique to produce A356 alloy wheels with high mechanical properties.

Morphology evolution of eutectic Si in Ce-rich mischmetal (RE) modified Al-10wt.%Si alloy at different cooling rates was investigated. The morphology of eutectic Si and modification mechanism of RE was investigated by scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The results showed that the RE modified eutectic Si exhibited a plate-like morphology under the low cooling rate (~100K/s). When cooling rate increased to ~600K/s, some branches were observed on the eutectic Si. In the RE modified alloy with a higher cooling rate (~1000K/s), the number of the branches on RE modified eutectic Si increased, and the morphology of eutectic S was modified to coral-like structure. The addition of Sr caused a flake-to-fiber modification of eutectic Si at low cooling rate, and the fiber size decreased with cooling rate increasing. The morphological observations indicated that the morphology of eutectic Si in RE modified alloy was significantly influenced by the cooling rate, while the modification efficiency of RE was lower than that of Sr.

In this study, the bulk amorphous alloys with 3mm in diameter were prepared at different voltages adopting copper mould suction casting method by adding microelement Al to Fe-Cu-Si based amorphous alloy respectively. The microstructures, glass-forming ability, mechanical compressive properties of (Fe0.34Cu0.47Si0.19)95Al5 amorphous composites annealed in different temperature were investigated. The results showed that re-melting of master alloy refined the solidified microstructure and homogenize the composition and microstructure. Moreover, the microstructure was stable with the increase of re-melting times. After relaxation and annealing at low temperature the majority of residual thermal stress was released during annealing at low temperature, with the enlargement of short-range order of amorphous microstructure and the decrease of the most adjacent inter-atomic distance. After proper annealing treatment the hardness and thermal stability of alloy were improved, indicating that the annealing treatment could improve the properties of amorphous alloy.

In this paper, the birch flour was the raw material with its particle size less than 100μm and the polyester hot-melt adhesive was used as binder with its particle size less than 60μm. The birch flour was dried using high speed mixer with heating function. The birch flour/polyester composite were prepared using the physical mixing method. The surface of the specimen and fracture surface of specimen were analyzed through the micrographs of scanning electron microscopy. In order to study the characteristics of laser sintering, the preheating temperature of the powder bed of laser sintering machine and the processing parameters of the birch flour/polyester composite were determined using single layer sintering method and empirical method. The tensile, flexural and impact specimens were built in the two scanning laser ways of subarea scan and progressive scan. The testing results show that the mechanical properties using subarea scan method are superior to those of progressive scan method and the mechanical properties of the specimens increase as the laser scan speed decreases. The best mechanical properties of SLS specimens of brich flour/polyester composite powder were obtained with the following parameters: the laser power was 11W, layer scan speed was 1800mm/s; layer thickness was 0.1mm; laser scan spacing was 0.1mm and the average tensile, flexural and impact strength of specimens were 1.35MPa, 3.69Mpa and 0.73KJ/m2 respectively.

Bamboo flour is a kind of a cheap reproducible natural plant powder. The polyamide hot melt adhesive (polyamide) is good bamboo adhesives. The bamboo flour/polyamide blend is prepared through mechanical mixing method. The powder bed preheating temperature of the laser sintering processing and the processing parameters of bamboo flour/polyamide blend are determined through the differential scanning calorimetry method (DSC method) and single layer sintering experiment. The mechanical testing parts are successfully fabricated by selective laser sintering using the bamboo flour/polyamide blend of 25/75 (wt/wt). In this series of experiments, the average tensile strength, flexural strength and impact strength of 5.9Mpa、11.5Mpa and 4.5KJ/m2 are obtained when the laser power is 11W, scan spacing is 0.1mm, the thickness of a layer is 0.1mm and scanning speed is 2000mm/s. The tensile strength and flexural strength of the SLS specimens are improved through wax infiltrating process, while the average impact strength of the wax-infiltrated specimens decreases compared with the SLS specimens processed under the same set of parameters. Bamboo flour/polyamide composite powder is new laser sintering with good forming property and low cost.

The software AUTODYN is used to investigate the damage mechanism of explosion in the brick and concrete buildings with different mass of charge in this paper. The results show that the mesh size of 5mm is very appropriate to study internal explosion; the maximum pressure area in the junction between roof and wall is broken up first and has the highest velocity, where is far from explosion source; the internal explosion damage in brick and concrete buildings appears in the boundaries between walls and roof.

Following with the development of construction industry, small diameter anti-sliding pile has been widely implemented in slope stabilization and deep foundation support. Much attention has been paid on researching lateral resistance of pile body. By orthogonally testing factors of small diameter anti-slide reinforcement pile models including concrete strength, sectional dimension and reinforcement bar gauge, The article analyzed sensitive influence to lateral resistance of pile body. The results indicate that concrete strength appears the most sensitive factor, next sectional dimension, and then reinforcement bar gauge. By comparing with shearing test of small diameter anti-slide reinforcement pile models, the conclusion follows that reinforcement of pile body does not fully unleash its shear resistance characteristic. Thus conclusion provides reference for implementation and designing of small diameter anti-slide pile.

Vinyl acetate, as an important kind of organic chemical raw materials, often adopts the distillation system to separate finished product from raw product. In addition to target products, some residues are produced in the process of distillation, which have a strong damage to the environment, therefore these residues are identified as hazardous wastes to manage and dispose in China. This paper, combined with literature analysis and site investigation, mainly studied production characteristics and particular pollutants of vinyl acetate distillation residue (solid and liquid). To conduct the analysis of the physical and chemical properties of distillation residue, and this paper applied the Gas chromatography-Mass spectrometry (GC-MS) to detemine main particular pollutants, containing Acetic Acid (relative peak area value of 63.47%), 1,1-Ethanediol Diacetate, Crotonic Acid, etc. Meanwhile, this paper can draw another conclusion that treatment and disposal of resource utilization distillation can make more significantly and efficiently use of vinyl acetate distillation residues through the technological contrast of GC-MS.

In the fabrication of SiC high-temperature sensors, the phosphosilicate glass film (PSG) is deposited on the SiC wafer as the intermediate layer, achieving the bonding of two SiC wafers. The ease of bonding is affected by the PSG film thickness uniformity. In this paper, the flow field distribution in the LPCVD tube is simulated under different deposition conditions,obtaining the wafer surface uniformity of gas flow distribution, which was verified by the experiment, The aim of this work is to study the impact of several deposition conditions such as the location of SiC wafers, wafer inclination and wafer spacing on the thickness uniformity of PSG film. Experimental results show that SiC wafer position in the tube and its own inclination and wafer spacing affect gas flow field on the SiC wafer surface,leading to uneven distribution of gas flow, thus affect the thickness uniformity of PSG.

Refined copper to obtain high quality can use the electrolytic method; the copper cathode plate is applied to the electrochemical machining. In order to make copper cathode plate has high flatness, assuring electrolytic cell cathode and anode plate spacing, so that the purity of copper electrolysis precipitation is higher, so change the straightening plate method has become the urgent task of the enterprise. Through the computer simulation, the ANSYS/LS-DYNA computer optimization, analysis precise straightening device parameters, in ensuring the copper starting sheet straightening can meet basic factories requirements, improve the machining precise straightening machine and copper starting sheet straightening efficiency.

The basic structure and principles of rotary stream for sand reclamation device will be introduction. According to the principle of renewable rotary stream for sand reclamation equipment, combination with Fluent numerical simulation model to construct the old sand regeneration process. And according to the impact velocity control problem for sand, using discrete phase model and turbulent model, the sand movement tracking and turbulent kinetic energy and the blowpipe of equipment were analyzed, finally puts forward some suggestions for improvement.

In this paper, we put forward an innovation method of high-speed and real-time error diffusion, which is based on Floyd-Steinberg algorithm. The design introduces LUT(look up table) and pipeline technology instead of complex multiplication operations, which accesses to the memory frequently. The whole design uses Verilog HDL language to program and Quartus ii 8.0 to synthesize and layout. At the end of the paper, we use a 48 pixel as an example, then simulate and verify it on the Modesim, which can prove the correctness of the design. Compared with the standard Floyed-Steinberg algorithm, this design can reduce the computation complexity, use a smaller memory space to exchange lots of logic units and increase the throughput of the algorithm. Besides, it has the advantages of good reconfigurability, simple hardware structure and high real-time.

The generation III nuclear technology (AP1000) has been introduced into China since 2006 along with the project of 1000 MW advanced passive pressurized water reactors which is a development of any of the generation II nuclear reactor designs incorporating evolutionary improvements in design developed during the lifetime of the generation II reactor designs. The low pressure rotor of nuclear turbine for AP1000 is currently the heavy forging which requires the use of the heaviest steel ingot and possesses the maximum weight and cross sectional area in the world. The forming and manufacturing technology of such heavy forging have been described in this paper.

Because of the powerful data processing ability of FPGA, the fast interpolation algorithm is used for Bayer format data which comes from CMOS sensor MT9M011 to convert to RGB image format. In the RGB color space to YCbCr space conversion stage,using color space conversion formula, combined with the characteristics of FPGA, realize the conversion of RGB to YCbCr. Finally, correctness is verified by the experimental results which use SignalTap II embedded logic analyzer.

Some diseases, particularly cardiovascular disease, will change the shape and structure of retinal vessels. Observation and detection of retinal vessels play an important role in the diagnosis of diseases. Traditional diagnosis of the retinal vessels that ophthalmologist perform under artificial visual attending. Image segmentation based on Markov random field is a method based on statistical theory, which takes into account the correlation between the local pixels, uses the prior knowledge effectively, has fewer model parameters and is easy to be combined with other methods etc., so this method has been widely researched and applied in the field of image segmentation. This paper which mainly studied the Markov random field is how to specific apply to image segmentation, and the iterated conditional mode and the traditional segmentation (clustering) algorithm segmented and compared in the medical retinal vessel image. The method of MRF can effectively restrain the noise in the vessel segmentation.

A novel and improved waste pyrolysis test system is developed by process design, pyrolysis host type design and the corresponding counterpart type design. It contains the design of waste pyrolysis pretreatment device, the sealing feeding device, the pyrolysis slag cooling device, the high temperature pyrolysis gas dust removal device and the pyrolysis gas desulfurization dust removal device. This study proposes a good testing model and a production validation on waste combustion under the oxygen-free and high-temperature condition. Thus it offers an effective technical support and guidance on improving the utilization of waste calorific value and preventing the generation of dioxin.

Natural wind, relative position between the nozzle and the outlet of the ram in the air-assistant spray have a great influence on performance. Air-assisted boom sprayer model is developed based on CFD. According to the data of the related parameters of the spray machine, variables of 3-D model were defined. With velocity of natural wind and inlet of the ram , the spraying flow keeping constant, the relative position between the nozzle and the outlet being a research variable, this article calculates the drift rate of the droplets respectively, then analyzes the results scientifically and gets the corresponding conclusion. At the same time, in order to confirm the reliability of the simulation results, this paper makes an experiment, which is done in Shandong agricultural university spray performance laboratory. Studies have shown that drift rate is significantly lower when the nozzles located under outlet position than on the downwind or the upwind .

This paper mainly analyses a BAPV system of 3kWp and a BIPV system of 10 kWp in Shanghai, China. Net present value (NPV) and the payback time (Pd) as the parameters to determine the profitability of the system based on some actual measured data. As there are two subsidy policies in China, including the initial investment subsidy and PV electricity tariff subsidy. The variations of NPV and Pdwith the initial investment subsidy and PV electricity tariff subsidy are researched. Analysis results indicate both the systems have a good economic benefit. Since the manufacturing, utilization and recycling periods of PV systems can lead to negative impacts on the environment. Environmental impacts by both the systems are also evaluated in this paper by the energy payback time (EPBT) and greenhouse-gas payback time (GPBT). Results show both the systems have a good environmental benefit, PV technology and PV system are sustainable.

The performance of various noble metal based catalysts for the NOxreduction in the CO-rich conditions of simulated post Euro-IV diesel emissions at low temperature was investigated in this paper. Pd loaded catalyst showed higher catalytic activity than Ir or Rh loaded catalysts. Titania, as one of the support material, clearly promoted the deNOxprocess due to the synergy with alumina and Palladium. The TiO2loading was optimized subsequently. As a result, Pd/TiO2/Al2O3catalyst with Pd loading of 2.0 wt.% and TiO2loading of 10 wt.% showed the NOxconversions of 25~46% in the temperature range of 200~250°C.

PO/CB (Polyolefin/Carbon Black) PTC (Positive Temperature Coefficient) composite with easy processing, low cost characteristics has been applied widely. But it suffered from a relatively short lifespan because of its NTC (Negative Temperature Coefficient) effect and low PTC intensity. In order to overcome this shortcoming, the CF was calcination-treated to prepare LDPE/CF (Low Density Polyethylene/Carbon Fiber) PTC composite. Influence of length, content and treatment method of CF on PTC properties of composites was investigated. Results showed that 0.5mm length CF in composites had higher PTC intensity than that of 2mm length CF. PTC intensity of the composites was enhanced more effectively by calcination treated CF compared to the untreated CF. The maximum PTC intensity was 8.1 when CF’s content was at 8wt%.

The ABS/PC alloy was prepared, and the extrusion characteristics of the alloy melt was studied by a constant speed Double-capillary rheometer. The micromorphology of the blend was characterized by SEM, and extrusion processing property was also analyzed. The results show that, the ABS/PC alloy with the optimum processability properties can be obtained when the ratio of ABS to PC is 90/10, and mechanical properties of the alloy can meet the requirement of ship's magnetic compass cover. Morover, the processability properties of the alloy are sharply declined with the higher PC ratio in ABS/PC.

The fine grain, poor sorting and high cement content in low permeability reservoirs lead to poor reservoir property, low porosity and permeability and have strong damage to the reservoir .The conventional way of low permeability oil mining is mainly fracture and chemical flooding, which cost is relatively high and will cause serious irreparable damage to formation. People are in favor of physical oil production technology because it is no harm and pollution to the reservoir, more flexible to operate and it has wide range of application and low cost. By using high frequency pulse pressure servo system and ZC-type I, this paper examines the low-frequency vibration oil recovery indoor simulation test device hydraulic pulse oil displacement effect of low permeability cores. The experiment selecting the artificial core (permeability are less than 50), examines the effects of different hydraulic pulse parameters (frequency, static pressure and dynamic pressure) on low permeability core permeability and recovery factor. The results showed that only when the three parameter ,hydraulic pulse frequency, static pressure and dynamic pressure, suitably combined will greatly increase the reservoir recovery efficiency and reduce residual oil saturation.

—Feature extraction is a very important part in speaker recognition system. We proposed and implemented a speaker recognition algorithm based on the VQ and weighted fisher ratio of MFCC. To evaluate performance of this algorithm, we built a small speaker recognition system based on the MATLAB. Compared with the traditional feature selection methods, the characteristic vector obtained via this algorithm has the greatest degree of differentiation in the same dimension. According to the test results, the speaker recognition algorithm we proposed in this paper, can significantly increase the accuracy rate of training and recognition, and reduce the data required by calculation, in the case of keeping a higher recognition rate.

The 3D model retrieval technology has been widely used in many fields, then the 3D model retrieval based on content is proposed, feature extraction becomes the key to retrieve accurate or not, using wavelet transform combined with wave frequency method of feature extraction can partly solve the problem of ambiguity, the experiment proved that the algorithm improve the efficiency and accuracy of retrieval.

In this paper, experimental work has been performed to study the influence of temperature and particle volume fraction on the viscosity of aluminum oxide (Al2O3)-ethylene glycol nanofluids. Nanofluids with particle volume fraction at 1%-4% were examined. Viscosity experiments were carried out at 20°C-60°C. The results show that the viscosity increases as the particle volume fraction increasing, but decreases with an increasing of temperature. It is found that the relative viscosity is independent of temperature for a particular particle concentration, and independent of particle volume fraction at a certain temperature. Furthermore, formula of Chen was verified appropriately, and a correlation was proposed for computing relative viscosity.

For a long time,users electic larceny has been a headache topic of the electric power department.The users long-term electic larceny has brought great economic loss to the power supply department.In recent years,the stealing power means are emerging in an endless stream,and they have been broght mant difficulties to prevent electic larceny.But the road is high one feet evil spirite is high one a unit of lengh, according to the study on electic energy meter,we will understand the electic larceny means at the sours.Therefore, further study of stealing power means is also our current priority,only the better anti-stealing electic power means, can be completely blocked leak.

This paper describes the design of the gait mechanism of pedal lower limb rehabilitation robot based on people’s heel movement trajectory curve in the normal walking. It is established the kinematics mathematical model of a pedal lower limbs rehabilitation robot and the simplified three-dimensional model with Pro/e software, then it is simulated kinematics using ADAMS software. The simulation result is shown that this pedal lower limbs rehabilitation robot can achieve the expected rehabilitation exercise and run smoothly. Kinematics analysis and simulation of pedal rehabilitation robot is provided the necessary theoretical basis and parameters for the study of lower limb rehabilitation machinery.

The ingot of Sm-Fe alloy was prepared by vacuum melting. After a process of coarse crushing, it was made into Sm-Fe ribbons by melt-spinning. By analysis of XRD and SEM, it was confirmed that the ribbons composed of fine Sm2Fe17columnar grains with almost the same orientation can be obtained under the condition of 5~7m/s surface rotating velocity of Cu wheel, suitable nozzle size, injection pressure, temperature and composition of the Sm-Fe melt to regulate cooling rate and crystallization. The achievement of the ribbons lays a foundation for preparing anisotropic Sm2Fe17Nxmagnetic powders by rapid quenching.

In this paper, frequency domain analysis and application of electrochemical noise of X80 Pipeline Steel in Xinzhou Soil is researched. In the frequency data analysis of electrochemical noise, there are three characteristic parameters. It can be seen from experiments that X80 steel buried in Xinzhou soil with14% moisture content shows that metal corrosion is still not change much. And, it can be inferred that corrosion of X80 pipeline steel in Xinzhou soil with 18% moisture, corrosion is uniform while the morphology is not the uniform , it is the morphology that some pitting are connecting into the film. In Xinzhou soil with 22% moisture, potential PSD figure is different after corrosion happened for one day and three days. Thus, the corrosion type can be determined by high-frequency slope of the linear segment of potential PSD figure.