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The author designed a intelligential spray car of fruit tree, this support frame of worktable support the whole spraying arm in the course, its dynamic properties is important to determine the product quality and life. On the basis of three-dimensional modeling, The modal of dynamic that support frame was analysis and the first ten modal parameters (natural frequencies and mode shapes) was calculated by using ANSYS finite element of analysis software. Compared with Modal parameters by method and experimental modal analysis obtained, summarizes the higher modes of dynamic structure, and proposed modifications for the structure.

This paper deals with the aerodynamical problems of rigid flapping wing at low Reynolds numbers with emphasis on investigating the lift generation mechanism of simplified ornithopter. Theoretical analysis and Particle Image Velocimetry (PIV) were conducted to analyze and verify the lift generation conditions. The results revealed that the rigid flapping wing will generate lift under the conditions of both angle of attackαand free incoming flow velocityvwere not zero. With the wings flapped periodically, there were votexes formed, developed and shedding alternately. The calculation of curl demonstrated that the greater of flapping speed, the greater of curl. The statistic of circulation suggested that the circulation generation of flapping down was greater than that of flapping up, the circulation difference contributed to the lift generation. The difference of circulation will increase along with the angle of attackαin the circumstances of free stream velocityvand flapping speedπand flapping amplitudeΦmatched well.

To solve the problem of high-salt ballast wastewater treatment, biological contact oxidation process by combined packing used to simulate the experimental study. When dissolved oxygen is 5 to 6, water temperature is 18 ~ 20 °C, pH is 7~8 and hydraulic retention time is 48h, the Influence of salinity dips and swells process on sludge treatment system and its effects were investigated. The results showed that salinity shock loads on the system less affected COD removal, after 3-5 days short adaptability run, the system became able to restore effluent water stability. The influence of Salinity swells process on AOB, NOB and denitrifying bacteria was greater than a dip .Salinity plunged produced smaller impact on the total nitrogen removal, while in the salinity swells TN removal reduced from 70.7% to 42%.

We used a simple low-temperature hydrothermal approach to synthesize Ag nanoparticles (NPs) and demonstrated their efficiency as organic molecule detectors in surface enhanced Raman Scattering (SERS). Using finite difference time domain simulation, we described an investigation on the distribution of electric fields amplitude of the neighboring Ag NPs. The enhanced electric field is confined at the interparticle gaps and the enhancement factor can be further increased with reducing the spacing between the NPs. The theoretical simulation demonstrated good consistency with the experimental measurement results, which predicts an electric fields amplitude enhancement of 115 at the center of NPs gap and an electromagnetic SERS enhancement of 108. The evidence of clear correlations between SERS enhancement and morphology distribution offer a route to develop more effective SERS substrates.

Six dominant thermophilic cellulolytic bacteria were separated from undigested dewatered sludge. By analysis of their water content, value of hydrolysis up, rate of weight loss of filter paper and CMC-enzyme activity, a dominant thermophilic cellulolytic bacterium named XW5was separated and inoculated in the dewatered sludge under simulating bio-drying conditions. The results showed that water content of the dewatered sludge which was inoculated dominant bacterium was decreased from an initial 70.05% to 62.49%.

The construction of intelligent industrial park is an important part of intelligent power grid construction, and also a specific part in the national "Twelfth Five-year Plan". The development of the Internet of things is complementary to the construction of intelligent power grid, and also the key technology in the construction of intelligent park. With the development of software and hardware, the Internet of things will be more widely used in the construction of intelligent park.

DGreedy (distributed greedy) algorithm evaluates the priority level in view of remaining energy of terminals, and the relationships between neighbor nodes are not considered. At the same time, the adjustable sensing orientations of sensors are limited. Therefore, the network coverage ratio of DGreedy is affected usually by the processing order of sensor nodes. In this paper, an improved Greedy algorithm for the coverage in directional sensor network is proposed based on the principle of global greedy. The single coverage area of nodes is considered as priority. The direction of node with maximum single coverage area is deployed firstly. Thereby it reduces the sensing overlapping regions and accomplishes coverage enhancement of the networks. Meanwhile, in order to improve the network coverage ratio, the sensing orientations of sensors are adjustable continuously, so the best sensing orientation of node can be selected by considering the deployment of neighbor nodes. Simulation experiments show that the proposed algorithm can improve the coverage area effectively.

In order to improve beer sterilization effect of wastewater treatment, reduce the heat load of the sterilization wastewater on subsequent water treatment processes. In this paper, through optimizing transformation developed micro-flocculation -membrane treatment processes. Screening for the identification of inorganic polymeric aluminum ferric chloride flocculants as the technology. The best dosage was 15mg / L, the field test to verify the craft beer sterilized wastewater treatment effect. The results show that, micro flocculation membrane treatment process in the water after treatment of COD and turbidity removal rate is respectively 76% and 98%. To illustrate the use of this technology in the treatment of beer sterilizing water without two stage filtration, can effectively recycling sterilized wastewater.

Spray distribution uniformity is a very important performance of nozzle. This paper analyses the spray uniformity of the spraying machinery as well as the influence factors. Spray distribution coefficient of variation of nozzles varies with the different spray pressure, spray pressure and spacing. The nozzles of lechler ST made in German were tested to present the optimum spray height with different spray pressure and spray spacing through analyzing the trend of coefficient of variation varying with the different spray pressure, spray height and spray spacing. By the test, the greatest impact on spray uniformity is the pressure of the spray bar, followed by the height and the spacing of the spray bar. By analysis of the spray distribution coefficient of variation, we find the optimum combination of the spray pressure, spray height and spray spacing.

The paper introduced the source and harmfulness of heavy metal pollution in water environment and summarized the applications of the chemical method, physiochemical method and biological method in heavy metal pollution of sudden emergency accident. Meanwhile, the heavy metal pollution emergency processing technology of rivers, lakes and other water bodies were elaborated and the emergency engineering technology of heavy metal pollution in rivers and lakes were analyzed. Finally, the application of bioremediation on heavy metal pollution caused by sudden emergency accident was prospected.

The treatment efficiency of Da Huofang Reservoir water in low temperature and low turbidity period by Coagulation/Ultrafiltration process was investigated in pilot study, and the water quality treated by the process was compared with that by the traditional treatment process. When coagulant dosage is 30 mg/L, the average removal rates of turbidity, CODMn and UV254 were 89.2%, 47.3% and 52.8% respectively in the coagulation/ultrafiltration process, and the treatment efficiency was obviously superior to the traditional process. In the study of operation parameters optimization for Coagulation/Ultrafiltration process, the optimum membrane flux was determined that was 50 L/m2h. The cleaning membrane water was treated by coagulation sedimentation process, and the quality of effluent was good which was mixed with raw water for reuse, and the experiment indicated that this method did not affect the stable operation of Coagulation/Ultrafiltration process, eventually the water recycling rate was improved from 89% to 96.5%.

This article describes the simulation method of water temperature and the model classification of water quality in lakes and reservoirs, and classic model of ecosystem dynamics of lakes and reservoirs - BA model from the water quality parameters of the relationship between two aspects of the basic equations are introduced. On this basis, establish the eutrophication of ecological models of lakes and reservoirs.

This paper studies the impact of cooling and warming on shortcut and simultaneous nitrification and denitrification under low temperature. The results show that the effluent concentration of NH4+-N and TN gradually increased, the nitrite accumulation rate decreased when DO was 0.3~0.5 mg•L-1, sludge return ratio was 300%, PH was 7.5~8.5, temperature dropped from 15 °Cto 8°C. From 10°C to 8°C in cooling, the average nitrite accumulation rate was 58.17% in A (HRT=24h) reactor. During the system heating process, treatment effect of the system gradually changed for the better. From 12°C to 15°Cin heating process, the average nitrite accumulation rate was 74.39% in B (HRT=48h) reactor. The system treatment effect in B reactor was better by contrasting A and B reactors, therefore, we can increase HRT to reduce the adverse effects on the system due to the temperature decreases to enhance TN removal effect of system.

Bio-drying reduces the moisture content of sludge without other external energy consumption, this paper introduced the microbiological aspect of a bio-drying process ,and state briefly about the suitable scope of oxygen supply ,C/N ratio, pH of biomass and moisture content for a optimal heat generation.

Complex microbial inoculants are highly effective compound bacteria which are widely used in the removal of pollutants, such as organic matter, nitrogen and phosphorus in the paper, printing and dyeing, petroleum and high-salt wastewater. The development of complex microbial inoculants was introduced in this paper, especially their application and influence factors in wastewater treatment. Finally we put forward current problems and development prospects of complex microbial inoculants.

With nitrite or nitrate nitrogen as electron acceptor in the high salt conditons, halophilic denitrifying bacteria can transfer nitrite or nitrate to nitrogen, thereby purifying the high-salt wastewater. Halophilic denitrifying bacteria play an important role in the carbon and nitrogen removal of saline wastewater, such as petroleum, chemical industry, seafood processing and seafood farming. This article dissussed halophilic denitrifying bacteria screening, the main types and the corresponding morphological characteristics, then we focused on the research progress of main factors of halophilic denitrifying bacteria’s growth and nitrogen removal. Finally put forward the current problems of the research and development trend of halophilic denitrifying bacteria.

Maximum likelihood estimation (MLE) is a commonly used method of Weibull distribution, but it needs to calculate the transcendental equations which is based on the computer programming. In this paper, we established a new MLE model of Weibull distribution in a case of random censoring. And this model was proved feasible and correct via three examples. At the same time, the model can be used for a variety of censored data and complete life data of Weibull distribution of MLE.

The universal tool microscope is widely applied in geometric measurement, as the imaging method is a typical measurement methods. In this paper, data processing and calculation example to specify the method of image measurement of the external thread, Classifications have been carried out systematically in this paper on the origin of error of the universal tool microscope, the image- measuring methods was summarized.

The comparative analysis of a parabolic and hyperbolic flexible hinges were presented. The closed-form compliance equations in the working and non-working plane can be derived by using the Castigliano’s second theorem. In order to compare the relative performance of parabolic and hyperbolic flexure hinges, a ratio function between specific compliances of the two hinges is defined. We analyzed the non-dimensional ratios of working plane and non-working plane compliance to show the relative properties of parabolic versus hyperbolic flexure hinges. The analysis results has showed compared to a hyperbolic flexure, a parabolic flexure can produce more desired output and is slightly less sensitive to axial effects under identical loading conditions. Meanwhile, the comparative study on the parabolic and hyperbolic flexure hinges can provide a theoretical basis for choosing them.

Considering the effects of structural sizes of a parabolic flexible joint on its performance, compliance, sensitivity and accuracy analysis are performed in this paper. The closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions, and accuracy equations are also obtained by using the Castigliano’s second theorem. According to the closed-form compliance equations, the effects of the structural parameters, such as thickness, notch depth, length and width, on the compliance of flexible joint are analyzed, respectively. In order to explore the effects of variations of the structural parameters on its compliance, the sensitivity analysis is carried out. And the accuracy analysis of the parabolic flexure joint is performed. The analysis results have shown that the parameters have large influence on in-plane compliance, and have small effects on out-of-plane one. And changes of compliance are larger within initial small range of parameters, while it has small variation in larger size range. And the length of joint has no effect of sensitivity

A new research method that can estimate the demand of EV in China on the basis of vehicular emission inventory and carbon reduction restriction is put forward. By using MOBILE model and software, China vehicular emissions inventory is created. Then, the demand bill of EV is worked out, and replacement scale and proportion of EV are calculated too. In the conclusion part, quantitative data is given, offering theoretical support for the governments’ strategic policy-making in developing EV.

The vibration of a complicated pipeline connected with centrifugal pump has been studied by ANSYS. The first 32 natural frequencies and the first five modal shape of the pipeline system is obtained by Modal analysis. The result shows that its excited frequency is close to the 30th natural frequency of the pipeline system，which will result in resonance. Because excited force caused by pulsatile fluid in pipe can make pipeline to has a compulsive vibrations, harmonic respones analysis is used to determine continuous dynamic characteristics of pipeline. The critical frequencies of node with the maximal amplitude at 30th modal shape are 12.452Hz and 56.284Hz by investigating its spectrum image of displacement. The major principal stress at two critical frequencies, far exceeding the yield strength of material, is respectively -1223MPa and 621 MPa, which demonstrates that the pipeline are very incidental to be destroyed.

Experimental study on ultrasonic and electromagnetic roll-casting of magnesium alloy was carried out using a self designed and installed twin roll continuous horizontal caster . 2.5mmthickness and 200mmbreadth of AZ31B magnesium alloy casting strips were produced successfully. The results show that the ultrasonic and electromagnetic field is transferred into roll-casting zone and result in a great decrease of the grain size,the average grain size has decreased to 10～15μm from 60～70μm; and also improved the mechanic properties of the AZ31B magnesium alloy sheet, the tensile strength and yield strength and elongation and hardness are improved by 25%and 44.4% and 120.7% and 12%respectively. On this basis, the mechanism of grain refinement during cast-rolling process with ultrasonic cavitation and electromagnetic field effect are discussed.

Considering the increasingly wider applications of flexible hinge in the fields of micro-electromechanical and micro-positioning etc., the optimal design method of a parabolic flexible hinge is presented. According to the structure feature and force exerted on the flexible hinge, the closed-form flexibility expressions in the working and non-working plane can be derived by using the Castigliano’s second theorem. Meanwhile, the accuracy analysis of the parabolic flexure hinge is performed. The rotation angle of flexure hinge in the working plane is treated as objective function, and the constraints of optimization model are displacements in the non-working plane and one described the accuracy of hinge, such that the optimization model expressed performance requirements of flexure hinge can be established. Based on the optimization model, the optimization designs of parabolic flexure hinge are accomplished to acquire the optimized structural parameters. In conclusion, the study on the optimization design of the parabolic flexure hinge can provide a theoretical basis for its engineering applications

In order to the effects of structural sizes of a hyperbolic on its performance, sensitivity and accuracy analysis are performed in this paper. According to the structure feature and force exerted on the flexible hinge, the closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions by using the Castigliano’s second theorem. Meanwhile, the accuracy equations are obtained using the Castigliano’s second theorem. According to the closed-form flexibility formulas, the effects of the four structural parameters, such as thickness, notch depth, length and width, on the flexibility of flexible hinge are analyzed, respectively. In order to study further the effects of the structural parameters on its flexibility, we derive the sensitivity equations, and the sensitivity analysis is carried out. Meanwhile, the accuracy analysis of the hyperbolic flexure hinge is performed. The analysis results have shown that the parameters have large influence on in-plane compliance, and have small effects on out-of-plane one. And the changes are larger within initial small range of parameters, while be small variation in larger size range. And the length has no effect of sensitivity.

The effects of temperature on electricity performance and microbial activity were investigated in single-chamber microbial fuel cell with proton exchange membrane (S-PEM-MFC) using glucose as substrate with phosphate buffer solution(PBS). The results showed that S-PEM-MFC able to adapt to a wide temperature range of 11, 18, 25, 30 and 35°C. The open circuit voltage, polarization, power density and microbial activity of S-PEM-MFC were increased with increasing temperature from 11 to 30°C. The maximum power density were 193.8mW∙m-3 at 30°C. Compared to 30°C, the battery open circuit voltage increased by only 4.8% at 35°C, while the polarization and power density is almost the same. These results demonstrate that according to the principle of economy which 30°C should be the optimal operating temperature of S-PEM-MFC.

NaZnPO4was prepared by heat-treating precursor with Zn(NO3)2٠6H2O、H3PO4and anhydrous sodium carbonate as raw materials by co-precipitation method, and it was characterized with UV/VIS spectrophotometer、X-ray diffraction (XRD). The experiment results shown that the near-infrared reflection property of NaZnPO4was very good. when the heat treatment temperature of preparation of NaZnPO4was range from 400°C to 800°C, near-infrared reflection properties of products were similar. Among them, the products with the heat treatment of 600°C has the best near-infrared reflection property,which is reached up to 95.2% in average,while the near-infrared reflection of TiO2is 74.1% in average.

Electrical conductivity of silicon nanomembranes (SiNMs) was measured by van der Pauw method under two surface modifications: hydrofluoric acid (HF) treatment and vacuum-hydrogenated(VH) treatment, which create hydrogen-terminated surface; and one interface modification: forming gas (5% H2 in N2) anneal, which causes hydrogen passivated interfaces. The results show that thinner SiNMs are more sensitive to the surface modifications, and HF treatment can cause larger drop of sheet resistance than that caused by VH treatment probably because of Fluorine (F). Forming gas anneal can also improve the conductivity depending on the interface trap density.

The Al-40Si alloy modified by 1.0 wt% Sr addition was heat-treated using L9(34) orthogonal test. The mechanical properties were measured. The microstructures were analyzed using optical microscope. After heat treatment, the hardness decreases about one times. The eutectic matrix and primary Si phase are both refined. The primary Si phase is refined and homogeneously distributes in the matrix with the solution temperature and time increasing. The optimal heat treatment condition is that the solution temperature, solution time, aging temperature, and aging time are 550 °C, 18 hours, 200 °C, and 5 hours, respectively. In addition, the theoretical optimal value for the hardness is 20.6 HRC, which is coherent with the practical optimal value.

One superior iron and manganese bacteria were separated from the stable operation of porcelain granular BAF filters of removing iron, manganese and ammonia. The bacteria was domesticated at low temperature. By analyzing the sample water containing iron and manganese in the role of iron and manganese bacteria which was not domesticated and domesticated at different temperature, observing the Iron and manganese concentration with time going on, studying the bacteria’s removal of iron and manganese property and the domesticated effect. Studies show that: the selected bacteria with 1% bacterial liquid at proper temperature within 48h ,the removal rate of iron and manganese was 75% and 35% respectively;After domesticated at low temperature, the removal rate of the iron and manganese domesticated bacteria at 10°C was improved 0.4 and 2 times more than the before domesticated; The iron and manganese domesticated bacteria at 10°C did not grow at 4°C,but the bacteria’s removal rate was better than the bacteria cultured at 30°C,and the iron removal rate was improved from 23% to 35%,the manganese removal rate was improved from 5% to 11%.

Data clustering has been received considerable attention in many applications, such as data mining, document retrieval, image segmentation and pattern classification. The enlarging volumes of information emerging by the progress of technology, makes clustering of very large scale of data a challenging task. In order to deal with the problem, more researchers try to design efficient parallel clustering algorithms. In this paper, we propose a parallel DBSCAN clustering algorithm based on Hadoop, which is a simple yet powerful parallel programming platform. The experimental results demonstrate that the proposed algorithm can scale well and efficiently process large datasets on commodity hardware.

The Ge mole fraction (x) of Si1-xGexlayer was described by the C-V technique for Schottkey contact of single heterojunction Si1-xGex/Si, whose structure profile can be characterized by SEM image and EDS. Then the strained Si cap layer was grown on the Si1-xGex/Si, and C-V technique was used to determine the carrier concentration and structure of double heterojunction Si/Si1-xGex/Si. The change of the structure between Si1-xGex/Si and Si/ Si1-xGex/Si was also observed by this method.

Users often have imprecise ideas when searching the autonomous Web databases and thus may not know how to precisely formulate queries that lead to satisfactory answers. This paper proposes a novel flexible query answering approach that uses query relaxation mechanism to present relevant answers to the users. Based on the user initial query and the data distribution, we first speculate how much the user cares about each attribute and assign a corresponding weight to it. Then, the initial query is relaxed by adding the most similar attribute values into the query criteria range. The relaxation order of attributes specified by the query and the relaxed degree on each specified attribute are varied with the attribute weights. The first attribute to be relaxed is the least important attribute. For the relevant result tuples, they are finally ranked according to their satisfaction to the initial query. The efficiency of our approach is also demonstrated by experimental result.

The XML keyword search has been used widely in the application of XML documents. Most of the XML keyword search approaches are based on the LCA (lowest common ancestor) or its variants, which usually leads to the un-ideal recall and precision. This paper presents a novel XML keyword search method which based on semantic relatives. The method fully considers the semantic characteristics of the XML document structure. Based on the stack, the algorithm is also presented to merge the semantic relative nodes containing the keyword as the results of XML keyword search. The results of experiments have been identified the efficient and efficiency of our method.

Transparent poly(methyl methacrylate) (PMMA)/TiO2 nanocomposites have been prepared by solution mixing PMMA with organically soluble titania xerogel. The organically soluble titania xerogel in the form of amorphous phase has been synthesized via a simple sol-gel method, involving hydrolysis of tetrabutyl titanate (TBT) in trifluoroacetic acid (TFA) and gelation. The obtained PMMA/TiO2 nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscope (TEM), thermogravimetry (TG) and ultraviolet-visible (UV-vis) absorption spectroscopy. The results showed that the interaction between titania nanoparticles and PMMA macromolecular chains led to a homogeneous dispersion of TiO2 in PMMA matrix. The resulting PMMA/TiO2 nanocomposites showed improved thermal stability, high transparency and high UV-shielding efficiency with a small amount of titania xerogel (£3.0 wt%). The present work is of interest for developing a series of transparent UV-shielding nanocomposites.

With the development of Micro-electro-mechanical systems (MEMS) and Nano-electro-mechanical systems (NEMS), dimension of their parts is required to nanometer scale, and the characteristics of machined-surface of nano-scale parts affect strongly its application. Surface relaxation plays an important role to the characteristics of the machined-surface. In this paper, machined-surface of monocrystal copper used as the specimen of surface relaxation, and its surface relaxation process is simulated. The influences of surface relaxation on surface energy, atom array, surface roughness, surfaces hardness and surface residual stress of the monocrystal copper are analyzed. Results show that surface energy and surface hardness decrease due to relaxation; work-hardening can’t be completely eliminated by the relaxation; compression residual stress of the machined surface is changed gradually to tensile stress during the relaxation. These research results are very helpful to the application of nano-machined parts.

The modification of the pretreated wheat bran by extrusion technology and cellulose enzyme method was studied to improve the content of soluble dietary fiber and enhance product functionality. First ,the pretreated dietary fiber (DF1) was modified by extrusion technology to get DF2,then DF2 were modified by enzymolysis of cellulose enzyme . The results showed as fowllow: the optimum conditions for extrusion modification was 45% material moisture content, 25 r•min-1 feeding speed, 200 r•min-1screw speed, 70-90-110-130-150°Cextrusion temperature, and the SDF content of DF2 is 33.95%. the optimal enzymatic modification conditions for DF2 was 1:0solid-liquid ratio, 30U/g enzyme adding, 4h enzymatic hydrolysis time.

Biological aerated filter (BAF) was employed to remove iron, manganese and ammonia from groundwater. The filter was in continuous operation under hydraulic loading of 3m3/m2.h. The influence of air-water ratio, the removal effects of iron, manganese and ammonia respective, and the oxidation of the three pollutants, the change of dissolved oxygen along the filter depth were investigated in this research. And the results was obtained, that the optimal air-water ratio was determined by 3, which made the dissolved oxygen concentration in the filter central be 4.75mg/l, and the removal of iron, manganese and ammonia be above 90%, 99% and 87%, respectively. The efficient removal of manganese occurred in the central and lower parts of the filter. More iron was oxidated at the upper 0.75m of the filter, and the oxidation velocity of manganese and ammonia would be limited, when the inlet iron concentration was higher. Nitrification process consumed more dissolved oxygen, which made dissolved oxygen concentration decrease along the filter depth from 0 to 1.25m. The demand of filtration depth is 1.6m, for simultaneous removal.

Six dominant microorganisms including four kinds of Pseudomonas and two kinds of Bacillus were isolated from substrate sludge for improving the organic substance removal ability for the biological activated carbon filter (BAC). This paper examines the backwashing effect on the stabilization of these six microorganisms immobilized on the filter. The results showed the backwashing had more impact on bacteria stabilization of BAC filter during start-up period than the stabilization period. The biomass loss was 28.57% during the start-up period more than the stabilization period which biomass loss was 11.76%. The Scan Electron Microscope (SEM) and Denaturing Gradient Gel Electrophoresis of Polymerase Chain Reaction amplified 16S rRNA (PCR-DGGE) photos showed that the ecology of the population did not change with the operation. The biomass of dominant microorganism after air-water scour backwashing decreased during the start-up period and retained stability during long term performance.

This paper illustrates the results of an experimental study on the bending performance of concrete beams strengthened with near-surface mounted (NSM) FRP reinforcement. The critical parameter of the embedded length of NSM-FRP plates was investigated in particularly. The test results indicated that NSM-FRP reinforcement can significantly improve the strength and crack resistance capacity of the concrete beam, reducing the size of cracks. The embedded length of the NSM-FRP plate has distinct influence on the cracking and bending capacity, the flexural stiffness, and the crack developments of the concrete beam. As the embedded length increased, the bending capacity and the flexural stiffness increased correspondingly and the crack developed more intensively.

A systematic study has been carried out to investigate matrix properties by introducing nmSiO2 fillers into an epoxy resin matrix. The study has revealed that with shock wave method, nanoparticle infusion brings about superior mechanical properties to the matrix than what is usually given by the other method. The nmSiO2 is dispersed in a high-energy liquid shock wave pressure processing. The resulting structural composites have been tested under tensile loads to evaluate mechanical properties. Shock wave mixing utilized high-energy, high voltage transient shock wave in the water medium to process the material lying in the focal area. Nanoparticles tend to reduce void content of the nanocomposites and thus translate into increased mechanical properties. Focused, the influence of the high-energy shock wave method on the mechanical properties of nanocomposite were systematic studied. Using different processing conditions, the experiments were done to find the best processing. Overall, shock wave method is shown as a promising methode for preparation of aerospace epoxy composites.

Electricity can be generated during the wastewater treatment by microbial fuel cell (MFC). Effect of the anode pretreatment method, anode modification and electronic media in anolyte on electricity generation of a single chamber microbial fuel cell (SCMFC) with an air cathode was investigated by performance measurement of the MFC during one cycle of generating electricity. Results show that the discharge time of MFCs with stainless steel anode pretreated by NH4Cl and HCl is longer than that with anode pretreated by the distilled water and NaOH; the performance of MFC with anode pretreated by NH4Cl is the best; comparison with stainless steel anode and adhere activated carbon, the current of MFC with the stainless steel anode adhere the carbon fiber is the maximum and its Coulombic efficiency is the highest; The electricity generation characteristics of the MFC with the anode adhered carbon fiber and pretreated by NH4Cl and the anolyte added the electronic media is the best. The action of the electronic medium and the NH4Cl on the MFC is synergism. It's of great significance that the research results improve the performance of MFC by anode pretreatment.

The filter media from iron and manganese biological removal filter which w- as replaced by new termly can be re-used. The sand filter media was characterized u- sing the SEM and owns developed interspaces. Drying the sand filter media at 110°C, then inspect and analyse its character and mode of defluoridation。The results show as follows. Under the test condition ,the adsorption balance can come out in about 3 hou-rs , the fluoride sorption on the re-used matured filter media followed pseudo-second kinetics. The effect of defluoridation by the matured filter media will be better within the range of pH 3~7, and best at about pH 4.58. The primary mode of fluoride sorpti- on is chemism, but physical sorption is also in existence , and the adsorption isother- ms could be described by Langmuir equation. Contact-time is a vary important factor in the continuous-flow column experiment. The effect of fluoride removal is long，as the height of filter column is controlled as 40cm.The filter media from iron and manga- nese biological removal filter possess potential of perfect sorbent, space for deeply study and foreground of practical application.

Laboratory-scale tests for removal and recovery of nitrogen and phosphorus in human urine were conducted by magnesium ammonium phosphate precipitation (MAP) method. Proper Na2HPO4•12H2O as a phosphorus source and MgCl2•6H2O as a magnesium source were added to adjust the ratio of Mg2+, NH4+and PO43-. The effects of initial pH, (Mg2+): n (NH4+), n (PO43-) : n (NH4+), temperature, reaction time and stirring speed on removal and recovery of nitrogen and phosphorus in urine were studied by MAP method. Results showed that the optimum experimental conditions were at room temperature, pH, the molar ratio of Mg2+：PO43-：NH4+, reaction time and stirring speed were set 10, 1.2:1:0.9, 30min and 100r/min.

Acclimation of short-cut nitrification aerobic granular sludge with aerobic granular sludge and nitrification sludge as seed sludge in a sequencing batch reactor(SBR) by controlling the pH, influent ammonia concentration, temperature and other conditions. Experimental results showed that the short-cut nitrification aerobic granular sludge with high ammonia and COD removal rate (95%) was formed successfully, and SBR can run long-term stably. DO at 6.0~8.0mg/L when the nitrosation rate remained stable at 50% ~ 60%, and lower DO levels within the reactor (2.0~3.0mg/L) nitrosation rates of up to 90%. Mature short-cut nitrification aerobic granular sludge average diameter of 2~3mm in between, MLSS of up to 10.162g/L, SVI minimum up to 22.63ml/g, moisture content is only 81.93%, total nitrogen removal rate of 40%, and carbon-nitrogen removal capability.

The curing behaviour of an epoxy/nmSiO2 nanocomposites system composed of a bifunctional epoxy resin with an anhydride curing agent and nmSiO2 was investigated. Differential scanning calorimetry (DSC) was used to investigate the curing behaviour of the nanocomposites system. As for the nanocomposites system containing different amount of nmSiO2, the values of activation energy, reaction order, theoretic gelling temperature and theoretic curing temperature were evaluated by kinetic equations. And the effect of nmSiO2 on the curing reaction and the curing reaction mechanism of the system were discussed. The results showed that the curing rate of the nanocomposites system increased slightly with adaptively increasing nmSiO2 content, and the curing process is at 110°C for 1hr, 150°C for 2hr.