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Extracting dihydromyricetin from Ampelopsis grossedentata by water extraction method. The orthogonal test and single factor experiment were used to optimize the best extraction condition. The ratio of liquid and material is 20:1, extraction time is 90min, extraction temperature is 90°C,holding time is 1d. The results of comparison between two purification methods show: Purify with acetone and recrystallization with water is better. The purity of dihydromyricetin is high to 98%, recovery rate was 59.2%.

The paper takes network security guard as a dynamic process, each link of the network security technology throughout the entire firm information operation, namely design an integrated network security system, which includes firewall system, VPN system etc.. The system can meet the requirements of network security and the goals of design network security.

according to the real motion blur image restoration problems, analyze the difference between the image features and Simulation of real blurred images, this paper proposes a method that applied to real image degradation parameter estimation. First calculate the degraded image using cepstrum, taking the cepstrum to binary image using absolute value of minimum gray as the threshold, and then remove the center cross bright line; and then use formula of point to line to calculate the distance of bright fringe direction of binary image, that is direction of motion blur; the direction of motion blur is rotated to the horizontal direction by the degraded image center of rotation axis, divided the autocorrelation method to calculate fuzzy scale. To estimate the point spread function is take into the Wiener filtering algorithm to recover images, image restoration effect prove that parameter estimation results are correct.

Fuzz testing is a software testing technique,which provides invalid, unexpected, or random data to the inputs of a computer program to test the robustness and security of procedures[1]. For structured data like logging, the variant fuzz testing framework adopts a configuration file, apply traverse and stream processing to complete the structured fuzzing. This article starts with the features of the structured data, then introduces the design and implementation of the variant fuzz testing framework, including function modules, class structure, and logic processing. As a conclusion, this framework is compared with zzuf tool, and the advanced nature of this framework is elaborated.

In order to study the deformation mechanism of the weak layer in diabase dikes under long-term loading at a hydropower dam foundation, in situ plate loading tests were performed. A damage creep model which improved the five-parameter generalized Kelvin model was established to describe the creep behavior of the weak layer. In this model, the deterioration effect of the rock parameters is considered and the creep parameters of the rock deteriorate gradually. This model is applied in a slope design for a dam foundation at a hydropower station. Long-term stability of the slope after excavation is evaluated. It shows that when damage creep is considered, the displacement is larger compared with the case of ignoring damage creep. The study shows that the deterioration effect of the rock parameters is of full importance for the project design and construction safety.

Antibacterial layer was prepared on the aluminum surface by anodizing pure Al and electrodepositing Cu in the pores of the anodic aluminum oxide (AAO) membrane. The AAO membrane was generated by a two-step anodization process in oxalic acid solution. The electrodeposition of Cu was conducted in copper sulfate solution using alternating current. The structural characterizations by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and energy-dispersive spectrometer (EDS) show that Cu nanowires with an average diameter of 70 nm are assembled in the pores of the AAO membrane. The tests of antimicrobial properties against two typical bacteria of Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus) indicate that surface antibacterial layer of aluminum possesses excellent antimicrobial properties and the maximum value of the antibacterial rate can reach 99.9% both for E. coli and S. aureus.

The directional well technology is developing with the increasing demand for energy, and the computer science plays an important role, which not only decrease the design time of the directional well, but also improve the drilling accuracy. The application of computer in rotary steering system makes it possible to realize the intelligent Directional well system.

Ground soil was looked as porous medium, a three-dimensional finite element model of shell-liquid-foundation-ground was built, and the influence of soil parameters, filling liquid mode, and liquid height on the tank ground deformation was discussed. The research shows that the subsidence range caused by additional stress is the 0.3D range of the tank bottom edge outer; the influence of soil constrained modulus on settlement is remarkable, with constrained modulus decreasing, the tank ground settlement increases; with soil permeability coefficient decreasing, the tank ground settlement decreases; the ground settlement curve shape is decided by soil constrained modulus and permeability coefficient; the influence of filling liquid mode on the ground final settlement is very small ,but on the pore water pressure peak is remarkable.

In this paper, through dealing with the leakage protection of underground engineering,do the research in leakage protection problems of groundwater seepage caused by concrete cracks and foundation settlement in underground concrete engineering,for the structure with different crack leakage protection in different methods, is discussed in aspects of material selection, construction process.Especially for the water leakage problem of the concrete structure,the settlement of the structure caused by the settlement joint and the stretching of expansion joint caused by the air shrinkage and temperature change of concrete.Change the past with rigid material plugging, by reasonable selection of material, the comprehensive application of the rigid and flexible materials,to solve the problem of water leakage caused by structure settlement joint and expansion joint, so as to solve deformation instability problem on the structure of settlement joint and expansion joint after leakage.

t is one of important topics in social network research how to form member clustering according to potential social relations by automatic context-aware the user's behavior feature. This paper presents a context-aware mobile P2P social network framework, member clustering model and algorithm. The user's location information, environmental characteristics etc. are introduced to the clustering algorithm, which intelligently cluster to potential P2P social network. The experimental results show that the proposed approach and the algorithm have a higher response speed, load balance and adaptive ability.

A three-dimensional numerical simulation about gravel pile reinforcing liquefiable silt foundation was built, and the influence of gravel pile on the liquefiable silt anti-liquefaction was discussed. Results show that under seismic load, gravel pile has obvious cushioning effect, and compared with natural foundation, the maximum horizontal vibration acceleration of the gravel pile composite foundation surface layer is obviously decreased; drainage effect of gravel pile is very significant and the larger is the gravel pile permeability coefficient, the better is the drainage effect; as earthquake intensity largens, silt liquefaction scope increases; of both natural foundation and composite foundation, the pore pressure ratio variation with depth is that the middle is bigger than the top and bottom, and middle layers are more likely to be liquefied; the greater is the seismic acceleration, the larger is the shear stress.

SUSXM7 Cu-bearing austenitic stainless stee1 was conducted with special antibacterial heat treatment and antibacterial properties of the steel were studied. The experimental results show that a suitable amount of ε-Cu phases can precipitate from the matrix of SUSXM7 steel after solution treated at 1100 °C and aging treated at 650 - 850 °C. ε-Cu phases are granular with diameter of 100 - 200 nm. SUSXM7 Cu-bearing austenitic stainless steels possess excellent antibacterial properties. Antibacterial rates against two typical bacteria of Escherichia coli and Staphylococcus aureus surpass 99.0％ and are basically equal to that of Cu-bearing austenitic antibacterial stainless steel researched widely now.

The study was carried out under El-Centro wave with SAP2000, and the appraisal results on their anti-failure performances were presented under strong earthquake action based on theplastic-hinge theory. In the analyses, the geometric and material nonlinear effects were considered simultaneously. The plastic development level of the rods, the deformed shape and the failure type and the ductility were estimated by plastic hinge principle. The results show that the failure model of the structure under the earthquake wave action is the complicated combination of strength failure and elasto-plastic dynamic local buckling in deferent areas; When the structure reached its failure critical limit, only 14% of the rods enter into their plastic stage and the development of the plastic hinges is not sufficient; Its critical failure peak acceleration of EL earthquake wave when applied in the combination of three directions is 969gal, which is equivalent 2.425 times to the official seismic fortification level of 8 degree (major earthquake, 0.4g) and it can be served as earthquake victims shelter in the area of 8 degree seismic fortification; Its displacement ductility coefficient is 2.88, which shows the structure owns some energy dissipation capacity.

The water filling preloading method is the common ground treatment method adopted to reinforce soft tank foundation. The influence laws of load speed, soil parameters on the reinforced effect of soft tank foundation were analyzed by the three-dimension finite element numerical analysis procedure. The research shows that the fovea deformation of single tank bottom under preload is similar to the pan bottom shape; the influence of soil constrained modulus on settlement is remarkable and it also affects the settlement time curve shape; when the constrained modulus is constant, with the permeability coefficient decreasing, the surface doming phenomenon around the tank foundation increases, and the range of upheaval is related to constrained modulus; the influence of loading function on the final settlement is very small, but the influence on pore water pressure is remarkable.

This paper analyzes the settlement of storage tank group and the settlement characteristics with different loading methods. The result shows that the deformation of storage tank foundation is a tilted ‘hat’ in shape under the influence of group effect ,and different loading methods obviously influence the degree of plane tilt and non-plane tilt of tank foundation.

Based on the geometry irregularity of pavement, an expression of the traffic load was put forward. The influence law of design parameters of each part of highway and pavement geometry irregularity on vertical deformation of highway was discussed by the three-dimension finite element numerical analysis. The research shows that the vertical deformation range of highway under the action of traffic load is generally semi-circular; the influence of surface stiffness on vertical deformation is different in different horizontal positions of surface; the influence of subgrade stiffness and foundation stiffness on vertical deformation is remarkable, but that of course stiffness is small; the rational matching of all parts of highway can effectively reduce the vertical deformation; with the increase of geometric irregularity index, the vertical deformation increases significantly.

Engineering rock mass is a highly complex grey system, it is impossible to get all the parameters of rock mass by theoretical methods or field measurement approach. Underground engineering feedback analysis method is a reliable way to improve the design, optimization and construction. Based on the field data of underground cavern of a large-scale hydro-power station, the three-dimensional finite element model is established, and orthogonal experimental design and multi-objective optimization method are used for the rapid back analysis. This method could be used for obtaining the rock parameters by inversion calculating in the underground cavern construction of a large-scale hydro-power station. Meanwhile, the inversion parameters could also be applied in the excavation simulation for the next phase and the rock deformation and stability is predicted afterwards. The design and construction sectors are supposed to get its feedback in time, which effectively guarantees the stability of the surrounding rocks.

A series of hydroxyl conducting anion exchange membranes based on the copolymer of vinylbenzyl chloride, butyl methacrylate and fluoro-polyacrylate were prepared by radical polymerization, quaternization and alkalization. The reaction conditions of polymerization were discussed and the potential applications of the resulting membranes in alkaline fuel cells were assessed. The results show that the membranes have adequate conductivity for fuel cell application.

A practical saturated sand elastic-plastic dynamic constitutive model was developed on the base of Handin-Drnevich class nonlinear lag model and multidimensional model. In this model, during the calculation of loading before soil reaches yielding, unloading and inverse loading, corrected Handin-Drnevich equivalent nonlinear model was adopted; after soil yielding, based on the idea of multidimensional model, the composite hardening law which combines isotropy hardening and follow-up hardening, corrected Mohr-Coulomb yielding criterion and correlation flow principle were adopted. A fully coupled three dimension effective stress dynamic analysis procedure was developed on the base of this model. The seismic response of liquefaction foundation reinforced by stone columns was analyzed by the developed procedure. The research shows that with the diameter of stone columns increasing, the excess pore water pressure in soil between piles decreases; with the spacing of columns increasing, the excess pore water pressure increases. The influence of both is major in middle and lower level of composite foundation.

Stainless steel fiber is a new sort of soft industrial material developed in the past decades. The pure stainless fiber has a number of outstanding properties and is getting wider range of application in textiles which are used as industrial textiles. The tensile properties between stainless steel fiber and traditional textile fibers are quiet different. The property differences between stainless fiber and common textile fiber made the textile processing of stainless fiber difficult. Based on the testing of breaking force, breaking strength and breaking elongation rate, this paper analyzed the tensile characteristic of stainless fiber and discussed its effect on yarn quality.

Stainless fabrics are getting wider range of application because of its excellent properties such as high temperature resistance, resistance to corrosion, high efficient filter etc.. The property differences between stainless yarn and common textile yarn made the knitting processing of stainless yarn difficult. Based on the analyzing of the main mechanical performance characteristic of stainless yarn, this paper analyzes the effective measures should be taken for the smooth going of the knitting process.

Pure stainless fiber products have many excellent properties such as high temperature resistance, resistance to corrosion, high efficient filter etc.. Pure stainless fabrics are getting wider range of application in the field of industrial textiles. The property differences between stainless fiber and common textile fiber made the textile processing of stainless yarn difficult. Based on the testing of dynamic friction coefficient, static friction coefficient, breaking strength and breaking elongation, this paper analyzes the main performance characteristic of stainless fiber and the reasons that makes textile processing difficult. Countermeasures for fabric manufacturing are suggested accordingly.

Based on the geometry irregularity of pavement, an expression of the traffic load was put forward. The influence law of design parameters of each part of highway and geometry irregularity of pavement on dynamic response of highway was discussed by the developed two-dimension finite element numerical analysis procedure. The research shows that the vertical maximum vibration acceleration of pavement and subgrade attenuates according to certain trend along depth direction in different work conditions; with the foundation stiffness increasing, the vertical maximum vibration acceleration of base course and cushion increases gradually, and that of pavement surface, subgrade and foundation decreases, and the decreasing amplitude increases gradually along the depth direction; the size of the influence of subgrade on dynamic response of highway is relevant to itself stiffness; the rational matching of all parts of highway can effectively reduce the vibration response; with the increase of geometric irregularity index, the vertical maximum vibration acceleration and maximum dynamic stress of pavement and subgrade increases significantly.

Styrene/Sodium allyl sulfonate copolymer (St-c-SAS) were prepared using soap-free emulsion polymerization method and boiling at high-speed stirring, and it was acided to obtain an efficient, stable, reusable new solid acid catalyst styrene/acrylic acid copolymer (St-c-AS). Elemental analysis and acid–base titration techniques showed that St-c-AS have high concentration of sulfonic groups. Differential thermal analysis (DTA) and thermogravimetric analysis (TG) results showed that the sulfonic of copolymer was hard to fall off at high temperature. Esterifications of acetic acid with ethanol showed that St-c-AS has high catalytic activity, and the catalyst can be reused without separation of 10 times, the esterification yields close to or exceed 100%. The superior performance of St-c-AS is attributed to their unique features including large surface area, high content of sulfonic groups as well as high temperature resistance.

Trust plays an important role in the development and implementation of P2P e-commerce systems. This paper proposes a novel Trust Evaluating Model Based on Reputation with Multifactor. By introducing many comprehensive trust factors in computing trust level and improving the computing methods of the local reputation and global reputation, this model can not only accurately reflect the node’s trust level, but also reduce the time complexity in computing trust level. Experimental results show that the trust model can improve the rate of successful trading compared with the existing trust models, and can be effectively applied to the P2P e-commerce system.

In this paper, cobalt, tungsten and molybdenum were co-diffused into the surface of T8 steel by double glow discharge technique. A carbide layer with M6C＋MC was formed on T8 steel. Under the carbide layer was a diffusion layer of W,Mo,Co. Hardness of carbide layer is high over 1200~1400 HV0.025 and can improve to 1400~1600 HV0.025 after solution and ageing treatment. Hardness of the diffusion layer is only 400~550 HV0.025, but it can improve to 800~1000 HV0.025 after solution and ageing treatment. The carbide layer combides with the substrate in metallurgy and can not peel off from the substrate. The carbide layer on T8 steel possess same good tribological properties of M2 steel.

The surface age alloy of Fe-Co-W-Mo was formed on 25Cr2Mo2V steel by double glow plasma surface alloying technique. The effects of processing parameters on the depth, composition and constituent phases of surface alloying layer were investigated. Results indicate that the plasma processing parameters influenced significantly the surface alloying process. The composition of the surface layer nears W11Mo7Co23Fe59wt%, the depth of the surface alloying layer is 150μm after processing at 1100°C for 6hr. The microstructure of the cross section was composed of three sub-layers, that is, the deposition layer, the diffusion layer and the matrix. The constituent phases of the deposition layer were Fe7W6 type μ phase Fe2W type laves phase, Fe3Mo and a little amount of M2C type carbide, that of the diffusion layer were α-Fe and some intermetallics.

Using a special impulse device, the impulse electroless Ni-P alloy plating were prepared. The microstructure、crystallization and the starting activation energy for crystallization was investigated by TEM、XRD and DTA, compared with electroless Ni-P alloys plating. The results showed that the diffractive ring was wider when using impulse, depositing temperature dropped up to 65°C,and crystallization temperature rose up to 310°C. Furthermore , the starting activation energy for crystallization and crystallization temperature of impulse electroless Ni-P alloys plating measured were more than that of electroless plating in the heating rate at 5、10、20、 40K/min, and it was also higher in the amorphous disorder degree and the starting crystallization temperature. Impulse electroless Ni-P alloys plating had better performance of thermal stability.

Tungsten, molybdenum and cobalt were co-diffused into the surface of undecarburized 45 steel at 1150 °C for 6 hours by a double glow plasma surface alloying technique. A Fe-W-Mo-Co type gradient surface alloyed layer with very low carbon content was formed. Thickness of the surface alloyed layer is 225.2μm. Concentrations of alloying elements Co, W and Mo in the alloyed layer are mostly ranged from 21 to 14 wt.%, 12 to 6 wt.% and 7 to 5 wt.%, respectively. The concentrations of alloying elements basically meet the requirements of W11Mo7Co23 type age-hardened high speed steel. The alloyed samples were solution heat treated, ageing and high-temperature tempering. The results show that the surface alloyed layer formed on 45 steel exhibits very strong age-hardening property and anti-temper softening ability as the metallurgical age-hardened high speed steel, the surface age-hardened high speed steel on ingot and decarburized carbon steel.

The forming methods of tube carton or box have three kinds. This paper mainly analyzes the noticed points of the design on the edge of the joint size of box from gluing and nail. The edge of the joints size of adhesive paper box should be corresponding less 0.5~1.5 cardboard thickness, and the nail rated-locking carton should be more 0.5 cardboard thickness compared with the opposite of the carton.