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Aiming at the shortcomings of large volume, high cost and long detection cycle of traditional solid propellant aging detection methods, a solid propellant aging detection method based on impedance spectroscopy is proposed. Firstly, the internal impedance of the solid propellant changes after aging, and a portable solid propellant impedance spectrum acquisition system based on impedance spectroscopy is designed based on the principle of electrochemical impedance spectroscopy, and the real and imaginary parts of the impedance spectrum are obtained. Secondly, in order to reduce the data dimension of the classification algorithm, the KPCA (Nuclear Principal Component Analysis) feature extraction algorithm is used to extract the impedance spectrum features of the solid propellant. Then, according to the impedance spectrum characteristics, the BP neural network is used for classification training, and the correspondence between the impedance spectrum and the aging time is obtained. Finally, the feasibility and effectiveness of the proposed method are verified on the physical platform, and the results show that the proposed method has the advantages of high precision and accurate classification, and can effectively predict the aging degree of solid propellant.

MIM technique is described in which allows for the production of highly porous metallic foams with porosity levels up to 90%. It makes use of the pressure built up by the decomposition of a foaming agent which is incorporated in a foamable precursor copper material obtained by powder compaction. A suitable behaviors feedstock that refers to its rheological is one of the key factors to ensure the successful of MIM technique and to predict failure, whether due to the binder component and compositions, powder loading or unsuitable process parameters. Potassium carbonate and polyethylene is added and were mixed homogeneously to form a copper feedstock. The rheological results in term of shear rate, shear stress, viscosity, melting rate and softening temperature which related to pseduoplastic behaviors have been conducted using a capillary rheometer (CFT-500D, Shimadzu) at various temperature and loads. The result has indicated that the viscosity of the feedstock is decreased with increasing shear rate thus proved the feedstock to be pseudoplastic.

The demand for components manufactured by Metal Injection Molding (MIM) has been increased due to a diverse range of applications on the high temperature mechanical properties and corrosion/oxidation resistance. Super alloy utilize the inherent physical properties of heat-resisting alloy based on iron-nickel, or cobalt specifically high purity and fine particle size distributions, which can enhance sintering and maximize the density of the final component. The development of super alloy Inconel 718 (IN718) using MIM is discussed. IN718 powder with binder formulation consists of polyethylene (PE) / palm stearin (PS) were mixed homogeneously and injected to produce green compacts. The binders then were removed through solvent extraction process from various heating temperature and duration of time. The binder removal was quantified by weight loss measurements and the evolution of pore structure for the debound specimens was observed using scanning electron microscope (SEM). Result shows that complete extraction of PS from the green parts can be concluded during 60 °C of heating and 6 hours of immersion in heptane.

Multilayer coating onto orthopedic implants has been studied extensively due to their excellence mechanical and biological properties. A multilayer coating was coated onto metal implants to prevent the leaching of metallic ions into human body. This paper aims to study the hardness of multilayer coatings of Chromium (Cr), Chromium Nitride (CrN), Chromium Carbonitride (CrCN) and Zirconium Nitride (ZrN) by Physical Vapour Deposition (PVD). The deposited multilayer coating was characterised by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD) and Energy Dispersive X-ray (EDX). Cr, CrN, CrCN and ZrN have been successfully deposited onto stainless steel substrates by PVD. XRD analysis detected major peak in preferred orientation of (200) and other peaks with (111), (220), (311) for CrN cubic phase. For CrCN, XRD analysis detected only low intensity peaks of Cr7C3 and ZrN peaks with preferred orientation of (111), (200) with other peak (220), (311) and (222). Microvickers Hardness results showed an increment in hardness value from substrates with 160HV to 174HV for Cr, 236HV for CrN, 362HV for CrCN, 364HV for ZrN and 370HV for multilayer coatings.

The dynamic testing of large-scale structures continues to play a significant role in earthquake engineering research. The pseudo- dynamic test (PDT) is an experimental technique for simulating the earthquake response of structures and structural components in time domain. A CFST-RC pier is a modified form of CFST laced column in which CFST members are connected with RC web in longitudinal direction and with steel tube in transverse direction. For this study, a CFST -RC pier is tested under three different earthquake time histories having scaled PGA of 0.05g. From the experiment acceleration, velocity, displacement and load time histories are observed. The dynamic magnification factors for acceleration due to Chamoli, Gorkha and Wenchuan ground motions are observed as 12, 10 and 10 respectively. The frequency of the pier is found to be 1.42 Hz. The result shows that this type of pier has excellent static and earthquake resistant properties.

Electromagnetic micro-punching is a novel micro-punching process in which metal foil occur plastic deformation until shear fracture under magnetic impact load. In this paper, electromagnetic micro-punching process was investigated on T2 copper foil. Effects of discharge energy, foil thickness and discharging time on micro punching were discussed. The results show that micro holes were successfully pierced with the discharge energy more than 5.0 kJ on copper foil of 20 μm in thickness. Foil thickness is the main factor in electromagnetic micro-punching with the discharging energy of 7.2 kJ. In addition, increasing discharging time can punch micro hole on thicker foil. The micro holes with diameter of 0.4-1.4 mm were successfully punched on 20 μm copper foil in thickness with discharge energy of 7.2 kJ.

As the tendency towards weight reduction and low fuel consumption seems to drive the increased use of advanced exotic materials such as composites, titaniums and Inconels in the aerospace industry, the need for machining remains in aircraft industries as a post-processing operation. In the present work, the investigation of the influence of machining parameters on surface temperature when drilling CFRP using 4 mm-diameter 2-fluted carbide end-mill coated with diamond is presented. The temperature was examined on Thermal Gun Quicktemp 860-T1 sensor and analysed based on analysis of variance (ANOVA) of Central Composite Design of experiments and a first order mathematical model has been developed to predict temperature values for range of machining parameters used in the study. The relationship between the machining variables and output variables is established. It was found that the lowest temperature (32.2°C) was generated at rotational speed, 537 rpm and feed rate, 180 mm/min and at the highest temperature (39.1°C) generated at rotational speed, 4400 rpm and feed rate, 270 mm/min.

A series of bulk ultrafine-grained (UFG) pure iron with grain size of 250-450 nm were fabricated by equal-channel angular pressing (ECAP) and annealing. Effects of ECAP passes on the corrosion behavior of the UFG pure iron were investigated. Results show that ECAP accelerates the acid corrosion rate of pure iron, but improves its anodic passivation property. The acid corrosion resistance of the UFG pure iron is restored through a large number of ECAP passes as well as through an annealing treatment. Annealing treatment is not good for the anodic passivation property of the UFG pure iron after a small number of ECAP passes. However, after a large number of ECAP passes (up to16), the corrosion resistance and anodic passivation property of UFG pure iron are less affected by annealing.

Because of the complex geologic space body and the underground seepage conditions, it is difficult to predict groundwater water inflow in prevention and treatment control work of coal mine. To predict the groundwater flow of the coal seam under the roof sandstone aquifer in Nanshan coal, the big water well method and three-dimensional numerical model were used at the same time. The quantity of predicted normal water inflow was 553.5 m3/h by using numerical model and the big-well method is about 591.6 m3/h. The result of big-well methods was relatively close to the result of numerical simulation method, which proved the rationality of the two methods in parameters selection and model building, and greatly improved the reliability and accuracy of prediction results. Compared with large-well method, by establishing the complex 3D geological structure of underground water and fitting the parameters based on the actual data of hydrology, numerical method could simulate the process of groundwater seepage and dewatering engineering, overcome the parameter uncertainty of large-well method, improve the predictive accuracy of the mine water inflow, and has important application value.

In this study, the variation of Zeta potentials and distribution of molecular weight in Extracellular Polymeric Substances (EPS) and soluble microbial products (SMP) were investigated. It is indicated that the salinity is effect on Zeta potentials significantly. When the salinity increased from 0 g/L to 35 g/L, the Zeta potentials decreased gradually. The average molecular weight is mainly over 30 KDa in EPS and SMP at 0 g/L salinity, and is mainly below 10 KDa at 10 g/L and 35 g/L salinity. This result is evident that the variation of molecular weight is contributed to high salinity.

In this study, high salinity wastewater was treated by an intermittently aerated membrane bioreactor (IAMBR) and the salinity loadings were set at 35g/L. The activated sludge was inoculated from the municipal wastewater treatment plant. The influent salinity level gradually increased from 0 to 35 g/L with every 5 g/L. With the salt concentration increased to 35 g/L, the performance of IAMBR was significantly affected by higher salinity. The removal efficiencies of the total organic carbon (TOC), ammonia nitrogen (NH4+-N) and total nitrogen (TN) were about 83%, 70% and 51%, respectively. It is indicated that the domestication of activated sludge from municipal wastewater treatment cannot obtain a better performance at high salinity.

The foamed polypropylene (PP) with excellent thermal insulating property was prepared by using the nanosilica (SiO2) aerogels as nucleators, followed by mould pressing foam in cross-link. The weight ratio of SiO2/ PP, which was at the range of 0~ 2%, significantly affected the morphology and thermal insulating properties of the foamed PP. The results showed that the foamed PP can get excellent properties when the weight contents of SiO2 aerogels was 1 %. The foamed PP with low density as 0.43 g/cm3and thermal conductivities at the range of 0.046~0.507 W.(m.K-1) was obtained by using this method.

Hydroxyapatite, (HAp), Ca10(PO4)6(OH)2, is recognised as biomaterial that widely used for orthopedics due to its similar to the inorganic component of human bone and enamel .The elements of HAp are primarily calcium and phosphorous, with a stoichiometric calcium to phosphorous ratio of 1.67 capable of promoting bone growth. Enormous amounts of by-product wastes from fishery factory lead to generating an undesirable environmental impact. Thus, this study was conducted to obtain biological natural HAp extracted from tilapia fish bones from fishery factory. Therefore, fish bone can be as cheap resource to produce HAp and crucial contributions in medical application. The fish bones of tilapia were boiled at 100°C to remove adhere meat and other impurities. Later, were milled for 1 h to form fine powder. The powder was calcined at temperature of 800° C and 1000° C for 3h respectively. The XRD result revealed the presence derived HAp and coherent with Joint Committee on Powder Diffraction Powder Standard data and the Thermo Gravimetric Analysis was carried out to show the thermal stability of the HAp powder. SEM results shown hexagonal particle sHApe obtained from HAp powder. The findings present a promising future regarded on producing high added value product such as hydroxyapatite (Ca/P ratio 1.757) from fishery wastes beneficial to medical application.

In order to build an accurate spray model for studying the characteristics of n-butanol and diesel blends. First, the calculation of gas-liquid two phase flow inside the nozzle was carried on, the birth and development of cavitation and the non-uniformity of the velocity field inside the nozzle were analysed. Then the spray model coupled flow inside the nozzle was established and verified. The spray simulation calculation of n-butanol and diesel blends was carried on by using the model, and compared the results with the results of flow inside the nozzle not coupled. The results show that the droplet speed, spray penetration and SMD of D100 and N40 is all bigger under the condition of without coupling flow inside the nozzle. The flow inside nozzle will affect the whole spray process and spray characteristics, which will ultimately affect the combustion and emission characteristics. So the spray model coupled flow inside the nozzle can provide accurate initial condition for spray calculation, which can reflects the fuel spray characteristics truly.

Brick is one of the most common masonry units used as building material. Due to the demand, different types of waste have been investigated to be incorporated into the bricks. Many types of sludge have been incorporated in fired clay brick for an example marble sludge, stone sludge, water sludge, sewage sludge and ceramic sludge. The utilization of these waste materials in fired clay bricks usually has positive effects on the properties such as lightweight bricks with improved shrinkage, porosity, and strength. Therefore, the objective of this study is to incorporate different percentages of mosaic sludge and investigate heavy metals leachability from the mosaic sludge brick. Heavy metals leachability was conducted by using toxicity characteristic leaching procedure (TCLP). Physical and mechanical properties were also determined which are compressive strength, shrinkage, density and initial rate of suction. From the results obtained, it shows that fired clay brick with 5% of mosaic sludge obtained the best result with highest compressive strength and low initial rate of suction (18.76N/mm2 and 10.08 g/mm2) respectively. Nevertheless, all the other properties for all bricks incorporated with different percentages of mosaic sludge were also complied with the BS 3921:1985 standard. The results also demonstrated that the leachability of potential heavy metals in mosaic brick were complied with USEPA (1996) and EPAV (2005a) regulatory limit. In conclusion, mosaic sludge could be an alternative low cost material for fired clay brick as well as providing a disposal method for mosaic sludge waste.

To achieve short-take-off-and-landing (STOL) performance, numerous airframe/propulsion integration (API) technologies have been developed for military and commercial transports. Powered lift technology refers to a concept of utilizing the propulsion exhaust flows to increase lift through an increase in wing circulation []. Over the past seventy years, various concepts have been explored to accomplish this goal. From the point of view of technical characteristics, powered lift concepts can be sorted into three groups: a circulation control wing, blown flaps, and jet wing. Most of other concepts are slight deviations of these three.

The austenite steel after rolling was radiated by the alternating magnetism, and the effects that alternating magnetic on the austenite transition was studied. The result shows that the alternating magnetism promotes the austenitic grain growth of low carbon steel. If the magnetic field intensity is increased, it could provide better performance of raw materials to cold rolling processing.

The outer space of city, construction space and underground space are city’s material spaces with disaster prevention function and are direct carriers of disasters, this paper propsoses the concepts and approaches to integrate, recombine and share city spaces based on the current situation of city’s disasters and spaces for disaster prevention, puts forward ideas and concepts including “ active disaster prevention”, “comprehensive disaster prevention”, “evacuation center” combining the latest research development of nanjing city’s comprehensive disaster prevention planning, and conducts deeper research in aspects of improving the disaster prevention function of city space and inspring planning and construction of city disaster prevention.

In this paper, the desorption temperature of adsorption bed in typical weather condition is studied though the solar adsorption refrigeration experiment with conditions of different weather. The results showed that: the better the weather condition is, the higher the highest temperature of the adsorption bed is, so the better the effect of desorption is. No matter in cloudless sunny or partly cloudy sunny conditions, the desorption temperature of adsorption bed can reach 93.4°C, and the amount of desorption also will be larger; however, in cloudy weather conditions, desorption temperature can reach 88.5°C, and desorption quantity is relatively fewer than it in cloudless sunny days.

Pro/Engineer (Pro/E) was applied to design a new kind of motorcycle belt pulley straightening machine, which was composed of electric cylinder and stepper motor in this paper. The effect of positioning and correcting were achieved by the straightening machine during operation. The motion simulation for correcting key parts was done under mechanical module of the software. The mechanism motion speed and the motion trails of the straightening machine were acquired under different positioning accuracy. Through analysis on the motion trails, the best range of the correcting parts′ rotational speed can be optimized.

In order to researching the microstructure of bioceramic coating on the surface medical titanium alloy (Ti–6Al–4V), the gradient bioceramic coatings are fabricated by wide-band laser cladding. The influence of multiple rare earths oxide La2O3 and CeO2 on microstructure of bioceramic coating were studied. The experimental results demonstrated that mixed La2O3 and CeO2 have an effect on forming-ability of HA\β-TCP in bioceramic coating and also refined the grain of bioceramic coatings. The largest amount of HA\β-TCP is presented among all the groups when the contents of La2O3 and CeO2 are 0.6wt.%, 0.4 wt.%, respectively.

To improve bioactivity of gradient bioceramic coating, the coating with two kinds of rare earth oxide was produced by wide band laser cladding technique. As the experimental results, whichadded0.6wt.% La2O3 fixedly, and increased the addition amount of the CeO2, when the addition of CeO2fulfill 0.4wt.%, the amount of HA-β-TCP is the largest in this experiment. Soaking the specimens in SBF for 14 days, the coating blended 0.6wt% La2O3 and 0.4wt% CeO2, then a great quantity of Ca-P white particles can be found on coating, which confirmation this bioceramic coating is of best bioactivity.

In order to improve the inherent safety of the Molten Salt Reactor (MSR), a concept of passive residual heat removal system (PRHRS) for the 10MW Molten Salt Reactor Experiment (MSRE) was put forward. Its transient characteristics were investigated by developing a model of it using C++ code. The effects of environmental temperature, finned tube number and chimney height on the PRHRS were analyzed. The results show that the PRHRS can remove the decay heat timely. Three natural circulations are established in the PRHRS when it begins to operate. With the decay heat power reducing, the PRHRS can automatically adjust its heat removal ability. It needs not any external power for the PRHRS to operate, which enhances the inherent safety and reliability of the reactor, especially under the condition that power plants lose power.

BCR three-step extraction method was used to evaluate the speciation of mercury in mining area soil. The results showed that the major existent form of mercury in NO.1 and NO.3 area were acid-soluble speciation, the major existent form of mercury in NO.2 and NO.4 area were nitric acid-soluble speciation, and the total content of mercury in entrance area, shade area, sunny area and low-lying area were 419.977 mg/kg, 182.945 mg/kg, 290.313 mg/kg and 798.718 mg/kg, respectively. The bioavailability of mercury in mining area soil was evaluated based on BCR speciation. Acid-soluble speciation, nitric acid-soluble speciation and oxidation speciation were considered to be potential bioavailability.

In view of the research in the existing forecast model and transformer DGA methods, this paper presents the collaborative model of intelligent concentration forecast of dissolved gases in transformer oil based on multi-Agent system, for improving the predictability of transformer fault. It presents the main function of each Agent, blackboard and JADE bus in this model, discusses the collaborative process of intelligent concentration forecast of dissolved gases in transformer oil based on multi-Agent system, and designs a combination forecasting architecture and a method of composition forecasting. Finally it indicates the feasibility and effectiveness of the intelligent concentration forecast model of dissolved gases in transformer oil based on multi-Agent system according to the application examples.

The objective of this paper is to optimize the design and structure of an airlift-driven raceway bioreactor via the computational fluid dynamics (CFD) simulation for microalgae cultivation. The calculated results showed that the airlift-driven raceway bioreactor had maximum average velocity when setting two airlift tubes (of 350 mm in length) in the middle, furthermore adding the inducing baffle structure. Under this condition, minimum dead zone ratio was obtained, which was advantageous to the microalgae cultivaiton.

Densification and settlement are two important behavior parameters of railway ballast under cyclic loading. This paper presents numerical simulation using discrete element method which studies the evolution of densification of railway ballast in specified region under cyclic loading. The simulation results show that with the increase of cyclic loading time, the densification of railway ballast under sleeper is also increasing, and the rate of increase becomes smaller and smaller. This paper presents a new full-scale complete railway track loading experimental facility which studies the evolution of settlement of ballasted railway track under cyclic loading. The experimental results show that with the increase of number of load cycles, the settlement of ballasted railway track is also increasing, and the rate of increase becomes smaller and smaller.

The high strength and high performance concrete C80~C100 is popularly used nowadays, especially in the West-Tower Project of Gungzhou. In order to provide reference for the use of high strength concrete and the development of ultrahigh pumping technology, the following six aspects were studied, namely the preparation of high strength concrete, the variation of the concrete mixture under high pressure, the index of the ultrahigh pumping concrete, the change after the pumping, the loss of the pumping pressure and the measurement of the pumping viscous resistance.

In the environment research, Sulfur Dioxide is one of the most important pollutants of the stationary pollutant sources and Sulfur Dioxide emission concentration is the important parameters of EPA pollutant monitoring system in the fomer study. NDIR is the common method on measuring Sulfur Dioxide emission concentration. The monodispersion soot difference position can change the collection acceptance angle of the received system and can influent the infrared light intensity, so Sulfur Dioxide emission concentration error is increasing. To reduce the monodispersion soot position interference, the interference is studied in this paper. The monodispersion soot different angle range infrared light intensity is calculated. Numerical simulation results show that the monodispersion soot difference position can reduce Sulfur Dioxide concentration measurement accuracy. The solution method is brought out and can improve the Sulfur Dioxide concentration accuracy.

Reductive ammonia leaching method was used to recover Cu and Co from heterogenite. The influences of the reductant quantity, leaching temperature, the concentration ratio of NH3 to (NH4)2SO4, leaching time and liquid-solid (L/S) ratio on leaching rate of cobalt and copper were investigated. The optimal conditions at which the leaching rate of copper and cobalt were 96.07%, 98.24% respectively and that of Fe, Mg and Al were almost 0 were as follows: time = 5 h, T = 50°C, the amount of ammonia is 1.2 times of theorrtical, C(NH3):C [(NH4)2SO4] =1:3, L/S ratio = 3:1, and the dosage of Na2SO3 is 0.5 times of the heterogenites mass.

The remote monitoring system is widely applied. The pollutant stationary source is distributed widely, so the pollutant emission status of the stationary source is difficult to on-time monitoring by EPA. The pollutant emission status remote monitoring system based on WEB and CAN bus is brought out in the paper. The remote monitoring system includes pollutant emission data collection unit, data transmission unit and EPA management unit. Soot emission concentration measurement method of the remote monitoring system adopts the Transmission-Scattering method and gaseous pollutant emission concentration measurement method adopts NDIR. The pollutant emission concentration data is collected by data collection unit and sent to data transmission unit through CAN bus. The pollutant emission data is sent to EPA management unit through WEB. The experiment result indicates that the remote monitoring system can on-line monitoring the pollutant emission status of the stationary source and improves the communication efficiency and accuracy.

In this study, 2024 Al alloy and AZ31B Mg alloy were brazing with mechanical stirring. The effects of brazing speed on microstructure and shear strength were investigated. The results show that oxide films on Al base metal surface broken completely at lower brazing speed. The continuous IMCs layer was broken into thinner one and blocky IMCs distribution in filler metal more evenly at lower brazing speed. The shear strength value near Al and Mg interface up to 53.1Mpa and 41.5Mpa respectively.

The disproportionation of AlCl was investigated by thermodynamics analysis. The results demonstrated that Gibbs free energy change of the disproportionation of AlCl decreases with decreasing temperature and increasing the AlCl pressure. The onset temperature of the disproportionation is 1521K in the standard atmosphere, and those are 878K and 1096K, respectively, at the AlCl partial pressure of 5Pa and 200Pa as the AlCl3 partial pressure is 200Pa. The AlCl equilibrium partial pressure is about 10-4Pa at 500K, demonstrating that the disproportionation of AlCl is complete below this temperature. The temperature in the condenser used in the experiments was below 1200K and the top near to the water-cooled cover of the furnace should be below 500K, therefore the disproportionation of AlCl occurred and was completed in the condenser.

VSC-HVDC is one of the proven solutions to the transmission problem of offshore wind power and the study of converter is the key technology. Mean value model of converter is introduced. The paper puts forward a method that can simplify the complex converter which is based on IGBT into a mean value model to improve the simulation speed. Through the simulation in Mat lab, the accuracy and high efficiency of simplified model are verified. The results show that the simplified model is feasible.

Aluminium used in beverage containers or cans is a sustainable material and can be recycled repeatedly. In Malaysia, the activities of collecting aluminium beverage cans for recycle normally involve a process of compressing aluminium cans manually in order to reduce storage space. The cans compression process is very time consuming and unproductive. In addition, there is no standard aluminium cans compressor tool that available in the market currently. As such, this paper aims to identify users requirements on the potential tool that could be used to compress aluminium beverage cans, follows by transform the important users requirements to a set of design criteria for the development of aluminium cans compressor. In line with this, six important factors that influence users purchase decision on household product were identified from literature review. The important factors were adapted into a questionnaire to collect and identify users preferred requirements on aluminium cans compressor via Voice of Customer technique. Subsequently, Pareto analysis and t-test were applied to define the most important and significant users requirements that influenced user purchase decision. As a result, a list of important users requirements is generated, which is also served as the design criteria for the development of a new aluminium cans compressor. Finding from the paper suggested that the most important design criteria for the potential aluminium cans compressor are consisted of safety, cost, performance and reliability requirements.

Ceramsite cellular concrete (CCC for short) is a kind of lightweight aggregate concrete. In this paper, the selection of materials and design of mix proportion have been discussed, and basic property tests has been done. The compressive strength was proved up to the National Standards of P. R. GB50003-2001(code for design of masonry structures), furthermore, elastic modulus and Poisson's ratio were also introduced. Questions remain regarding the quality control of the product, and further work is needed to resolve this contradiction.

Fiber-reinforced ceramic composites are relatively promising materials in aerospace and other high-tech area. In this work, the grinding mechanism of 2.5-dimensional woven quartz fiber-reinforced ceramic matrix composites was researched by experimental analysis. The acoustic emission (AE) combined with wavelet analysis was adopted to evaluate the grinding process. The ratio of energy which may indicate the mode of fracture of the composites was used for analyzing each of the AE signals levels. The effects of meso-structure on AE frequency distribution have been discussed. It was found that that specific frequency band is corresponding to the specific fracture mode, such as fiber fracture, interface debonding and matrix fracture. It indicates that grinding mechanism is highly dependent on the meso-structure of the composites.

A new unsymmetrical diarylethene derivative 1-(1, 5-dimethyl-2-pyrrolecarbonitrile) -2-[2-methyl-5-(4-aminomethyl) phenyl-3-thienyl] perfluorocyclopentene (1o) was designed and constructed successfully. Its optoelectronic properties have been discussed systematically, such as photochromic, kinetics experiments in acetonitrile solution and PMMA.

A new unsymmetrical photochromic diarylethene 1-[2-cyano-1, 5-dimethyl-4-pyrryl] -2-[2-methyl-5-(1, 3-dioxolane)-3-thienyl] perfluorocyclopentene has been synthesized, and its properties including photochromism, kinetics and fluorescence have been investigated in detail. The results showed that its photochromic behaviors could be modulated by UV/Vis light, changing from colorless to blue in acetonitrile solution.

The crystal structure of GdFeMn alloy has been investigated by using X-ray powder diffraction (XRD) followed by Rietveld refinement technique, differential thermal analysis (DTA) and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) techniques. XRD results showed that annealed GdFeMn alloy was a single phase of Gd6(Fe0.5Mn0.5)23 compound, with Th6Mn23-structure. SEM/EDS results and Rietveld refinement revealed that GdFeMn alloy was not really a new ternary compound as reported, but a solid solution Gd6(Fe0.5Mn0.5)23 which was only a point between Gd6Fe23 and Gd6Mn23. It was also found from DTA measurement that a reaction, Gd (Fe0.5Mn0.5)2 → liquid (rich Gd) + Gd6(Fe0.5Mn0.5)23, had taken place above 650.81 oC, and the educed Gd existed in educed part of GdFeMn sample. The results demonstrated the real structure of the GdFeMn compound as reported was Gd6(Fe0.5Mn0.5)23 compound.

Perturbation method is used to resolve one-dimensional wave equation under the assumption of small strain conditions. The relationship of the second order relative nonlinear coefficients (SORNC) β', the third order relative nonlinear coefficient (TORNC) δ' as the functions of fundamental and harmonic amplitudes is determined. The specimens are loaded from-200 MPa to 320 MPa at increments of 40 MPa by the electron universal testing machines. The SORNC β' and TORNC δ' are detected by the nonlinear ultrasonic testing system when ultrasonic waves propagate in the specimens. Results show that the relative nonlinear coefficients increase with the stress. The SORNT β' is approximately linear with the stress when stress is lower than 84.6% of the yield strength. The TORNC δ' is approximately linear with the stress when stress is lower than 76.9% of the yield strength.

The influence of AC frequency , the content of sodium sulfate and curing time on the electrical resistivity of cemented soil was studied. Firstly, the impedance modulus of cemented soil blocks were measured and their electrical resistivity were calculated; then the primary and secondary factors influencing on the electrical resistivity of cemented soil were determined through orthogonal method; finally , the influence of three factors on cement soil resistivity was discussed qualitatively. It is found that the primary and secondary factors influencing on the electrical resistivity of cemented soil are the curing time, the content of sodium sulfate and the frequency. The electrical resistivity decreases with the increases of AC frequency and content, whereas increases with increasing curing age.

The effect of calcium sulfate whisker (CaSO4) on mechanical property, melting, crystallization and rheological properties of polyamide 1012 (PA1012) was studied by differential scanning calorimeter (DSC), rheometer and material testing machine. It was shown that CaSO4 had no influence on melting temperate of PA1012, but can effectively enhanced nucleation ability of PA1012, which indicated that CaSO4 was good nucleation agent for PA1012. The viscosity and storage modulus of PA1012 firstly increased and then decreased as CaSO4 content increased. The results showed that CaSO4 had little effect on tensile strength, but impact largely flexural strength.

Cyclic Butylene Terephthalate (CBT)/carbon black (CB)/aluminum composites were prepared by melting blend method and their conductivity and mechanical property were studied by Milliohmmeter and material testing machine. The results showed that at below 1.6 wt% of flake aluminum（Al）, volume electrical resistivity and flexural strength of composites increased with Al content increases and reached the maximum value at 1.6 wt% of Al. Composites containing 18.4 wt% of CB and 1.6 wt% of aluminum exhibited excellent comprehensive performance (electrical resistivity, 20.3 Ω.cm; flexural strength, 40.0 MPa).

The Poly(vinylidene fluoride)(PVDF)/Cyclic Butylene Terephthalate (CBT)/carbon black (CB)/graphite (GR) composites were prepared by melting blend method and were studied by milliohmmeter and material testing machine. The results showed that due to the formation of CB and GR conductive network, the volume electrical resistivity of PVDF/CBT/CB/GR composites linearly decreased as graphite content increased at below 4 wt% of graphite, but it in turn increased when graphite content was higher than 4 wt%. Flexural strength showed an increase at below 1.6 wt% of GR and gradually decreased as GR content increased further. Differently, flexural modulus of composites declined as GR content increased. In all composites, the flexural strength was more than 25 MPa, which satisfied with the requirements of bipolar plates.

The purpose of the present study was to evaluate the effect of filler loading on the fracture toughness of light-cured dental resin composites (DRCs). The monomer Bis-GMA and TEGDMA (75/25 wt/wt) were mixed with treated micro-sized aluminum oxide (Al2O3) particles ranging from 40-60 wt% as filler. The composite samples were cured with LED for 80s. The bulk density (g/cm3) and apparent porosity (%) of the samples were determined according to the ASTM standard. The fracture toughness (KIC) values of the composites were determined using a single edge notched specimen in the three-point bending test. There was a significant difference in KIC of the composites with different loading of Al2O3 particles (p < 0.05). The highest amount of filler (60 wt%) reduced the KIC value to 1.5 MPa.m1/2. As a conclusion, the Al2O3 particles used as filler loading does have an effect on the mechanical properties of DRCs.

In view of orthogonal cutting, finite element simulation geometry is built. the friction model, thermal conduction model and chip separation model are established between chip and tool using Abaqus which is a finite element analysis software. Through a specific example, two-dimensional finite element model have been established, simulating the cutting process stress distribution of the work piece surface is also obtained during processing. While simulation analyzes the relationship between the rake angle and shear angle, the results of simulation and experiment are basically the same, thus further verify the credibility of Abaqus simulation results on orthogonal cutting, and the feasible is also proved of obtaining cutting data by the use of Abaqus simulation cutting process.

n order to lay raw materials foundation for increasing the performance of insulating brick with the low grade quartz sand along the Yangtze River, the quartz porous ceramic materials was researched in this paper. The results show the porosity of the porous quartz ceramics decreased with an increase in the sintering temperature. The pore is like the bowl shape, and the pore is closed pore, which is help to improve the heat insulation property of quartz porous ceramics. The CaSiO4 is produced in the ceramics after sintering processing. The shape is better, and the microstructure is circular and symmetrical pore, which is help to improve the mechanical property of quartz porous ceramics.

As the lack of work on comprehensive rock physical properties in deep geophysical exploration in Yudu-Ganxian ore concentration area, this paper focuses in comprehensive and systematic study about the comprehensive rock physical properties in this area. Known from the rock (ore) actual distribution in this area, this paper presents the comprehensive rock physical properties research method of the area, which use varieties of techniques to collect specimens systematic, determine the physical parameters, and even study the distribution characteristics and variation law of rock (ore) integrated rock physical properties parameters. In this paper, the results can provide the new information about integrated rock physical property parameters for understanding and explaining the integrated geophysical anomaly, providing the basis for the future in Nanling to carry out deep geophysical three-dimensional exploration and deep metallogenic prognosis.

This paper proposed a novel diagnosis algorithm based on Hurst exponent and BP neural network to detect carbide anvil fault in synthetic diamond industry. Firstly, a sort of preprocessing algorithm is proposed, which uses the sliding window and energy threshold method to separate the pulse from initial continuous signal. Then, some characteristic parameters which are based on Hurst exponent are extracted from the separated pulse signal. These characteristic parameters are used to construct fault characteristic vectors. Finally, the BP neural network model was established for fault recognition. Experimental results show that the proposed fault detection method has high recognition rate of 96.7%.