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Based on ASTM D 5961 standard, the double-shear bearing strength and effect laws for woven glass fiber/vinyl resin composite laminates are studied. By testing of various specimen, bearing chord stiffness line is properly determined according bearing stress range, and effect laws on bearing strength are analyzed when (±45)°/(0/90)°plies proportion and fastener torque get changed. The results show, with 40%~60% (±45)°plies proportion, the bearing strength and the offset bearing strength simultaneously reach to the high value region with small fluctuation. As fastener torque increases, bearing strength increasing trend gets slow while offset bearing strength first increases and then decreases.

A modified spreading dynamic model with feedback-mechanism based on scale-free networks is presented in this study. Using the mean field theory, the spreading dynamics of the model is analyzed. The spreading threshold and equilibriums are derived. The relationship between the spreading threshold, the epidemic steady-state and the feedback-mechanism is analyzed in detail. Theoretical results indicate the feedback-mechanism can increase the spreading threshold, resulting in effectively controlling the epidemic spreading.

This paper adopts a multi-component composite addition mode of adding polar and apolar additives with complementary advantages to manufacture a space for metastable pHase,and enhance the coordination ability of the surface of the environmental media ,in order to overcome the present method that whiskers nano-alumina were prepared under acidic conditions and the sheets were prepared under alkaline conditions. In addition, based on isomorpHous replacement of polar iron ions and intercalation of sulfate ions, this paper fully exerts the restoration function of crystal morpHology on apolar surfactant to establish an environment pHase system for crystallizing the required target product. This paper proves the existence of the added elements by energy spectrum and indirectly verifies the surface restoration function of the apolar granules by structural lattice.

Benzaldehyde was produced from oxidation of cinnamaldehyde by hydrogen peroxide in propylene glycol in the presence of sodium bicarbonate. Protic solvent demonstrated high selectivity and the yield of benzaldehyde could reach up to 82% in propylene glycol. The effect of solvent on the selectivity was attributed to hydrogen bond interaction between the oxidation intermediate epoxide and the solvent.

UKs day care services, including day hospital and day centre, have kept a very low profile in the sphere of health and welfare provision for older people. Day hospitals began somewhat earlier than day centers and originated in 1946 in psychiatric day hospitals in UK. Three sets of principles about user, staff and environment can be identified which have special significance for the design of the site of day care unit. Community care policies advocate that day services should be based in, and integrated with, the community, and easily accessible to local people. Day care unit depends on the design of the premises and their state of maintenance; these reflect providers' attitudes to the user group, and may convey a positive or negative impression of the service to the general public, including prospective users.

This study focuses on the internal layout of premises of UKs day care unit for older people, including possible combinations of rooms and spaces, access and circulation. All day units require a minimum of a dining/activity space, a kitchen, (a) toilet (s) and storage space, these rooms and spaces are combined into the basic type of premises. Depending on the aims of the unit, the number of places provided, and users' needs, many of the disadvantages associated with basic premises can be overcome if the premises have extra spaces. From the above analysis we can see that, in existing day unit premises, the number and type of rooms and spaces and how they are grouped together vary considerably, ranging from simple to complex arrangements. Also, the relationships between rooms and spaces in layouts for all day unit premises need to be pondered over, including distances between key rooms/spaces, the relative location of spaces in terms of their functions, the relationship between private and public spaces and the views within and between rooms, and from external windows. In addition, access and circulation of a day unit need to be considered carefully, including access to the day unit premises and the reception space and internal circulation.

Relative to the pharmacopoeia of high performance liquid chromatography (HPLC), establishing detection of puerarin in radix puerariae micellar electro kinetic chromatography (MEKC). Studying on buffer pH, borax concentration, separation voltage, SDS concentration of chromatographic conditions on the puerarin MEKC separation effect of influence, determined the best capillary electrophoresis conditions: test 250 nm wavelength, buffer of pH 9.0 0.1M KH2PO4solution-20 mM borax solution, separation voltage 18 kV, 40 mmol/L SDS concentration, 4.5 min retention time., grained puerarin MEKC standard equation: Y=36.522X-471.9, R2=0.9994(N=5), the puerarin concentration in 550 μg/mL to 750 μg/mL range comes out a good relationship. Get the lowest detection limit with 13.74 μg/mL. Puerarin content of the total isoflavone detected by MEKC was 45.35% that similar to 42.25% detected by HPLC. The method was stable, accurate, sensitive, possessed organic solvent consumption. The research results have applications in puerarin and its product quality evaluation system and promote isoflavonoids detection.

The corrosion failure analysis of an SA210 steel used in high pressure evaporator tube is conducted by XRD, SEM, OM. The result shows that the corrosion products in the inner wall of the steel tube is Fe3O4, mainly caused by the residual water in the evaporator tube corroding its inner wall with oxygen after the hydrostatic test of the boiler, finally leading to the corrosion leak of the tube.

Taking into account the heterogeneity of the underlying networks, an epidemic model with feedback-mechanism, time delay and migrations of individuals on scale-free networks is presented. First, the epidemic dynamics is analyzed via the mean field theory. The spreading critical threshold and equilibriums are derived. The existence of endemic equilibrium is determined by the spreading threshold. Then, the influences of feedback-mechanism, time delay, migrations of individuals and the heterogeneity of the scale-free networks on the spreading threshold and the epidemic steady-state are studied in detail. Numerical simulations are presented to illustrate the results with the theoretical analysis.

This paper takes the cold region as a background and stands on the point of architectural space, to analysis the problem of architecture space design with the use of responsive theory, aiming to explore an architectural space design method and theory to respond the specific climatic conditions.

Hydrogen-producing zymogenous bacteria YUAN-3 (Ethanoligenens harbinense) is used as the study object, on which the intermittent hydrogen production test is applied to examine the influence of Magnesium ions concentration on the growth and gas generation of YUAN-3. Research results show that when Magnesium ions concentration is 0.3g/L, volatile acid reaches the maximum level; when Magnesium ions concentration is maintained at 0.3g/L, the unit volume production of hydrogen reaches at 256mlH2/L，culture medium is applicable for hydrogen generation of YUAN-3.

Taking one foundation project as an example, a series of tests are carried out to study the dynamic compaction parameters and its effects on the deep collapsible loess foundation under super high fill in Lvliang region. Analyses are made on the average settlement of each test area before and after dynamic compaction and on the regularity of the main physical and mechanical indexes of soil. At the energy levels of 2000 kN•m, 3000kN•m and 6000kN•m, the main parameters are gained, such as the effective reinforcement depth, the centre distance of tamping points , the standard of stopping ramming, and the optimal ramming number; hence, the empirical formula of the effective reinforcement depth of dynamic compaction. The results of the tests show that the deep collapsible loess foundation in Lvliang region can be effectively reinforced by dynamic compaction, that the stability of foundation is good, and that the loess collapse in the reinforced range is eliminated basically. Moreover, after dynamic compaction above the energy levels of 2000 kN•m, the eigenvalue of the bearing capacity of collapsible loess foundation in Lvliang can reach over 300kPa; the deformation modulus of foundation soil is more than 25MPa. Therefore, the results of the tests can provide a reference for the design and construction of projects of the same kind; it can also provide a reliable basis for relevant norms and standards.

With the self-designed welding powder formula,this experiment employed the SHS reaction to weld the base metal,which was steel Q235 here,then respectively used Olympus large-scale horizontal digital microscope to analyze the structure morphology of the welding seam's different regions,JEOL SEM to point-analyze and line-analyze elements' distribution near the the weld interface and HV-1000 CCD automatic measurement microscopic vickers hardness tester to measure the microhardness of the pure copper's welding seam.The experiment's result shows the hardness of different part of the welded joint varies largely,and that the join of alloy elements can increase the microhardness of the welding metal,and that the welding metal and base metal interdiffuse,grow and mix remarkably near the fusion line,realizing wonderful metallurgical bonding.

Based on the high-speed photography, the effect of phase relations on droplet transfer and welding seam was analyzed. To each TCGMAW (Twin-wire Co-pool Gas-shielded Metal Arc Welding) torch at four-wire welding robot, under the descriptive welding parameters, when the phase relation of the front wire and the back wire was alternate, the arcs of the two wires had no effect on each other basically; the welding seam shaped very well. When the phase relation was synchronized, the arcs attracted each other and the two arcs centralized to the middle of the two wires; the humping bead was formed. When the phase relation was random, now and then the arcs synchronized and attracted each other, and at times the arcs changed alternately and had no effect on each other; the appearance quality of the welding seam was moderate.

Ship collision is a kind of dangerous accident which may result in serious damage of struck hull structure during shipping process. The damage of ship depends on the relative rigidity of striking ship and the capabilities of crash resistance of ship structures. The rigidity of bow is always considered as higher than that of side, so the structure of bow is regarded as rigid body. But this method is so conservative that the result of numerical simulation may be wrong when the rigidity of side of one ship is higher than that of bow of another ship. The process of collision of two ships is simulated, in which the structures of two ships are all defined as elastic body. The behavior of side is studied and some useful results are found.

In the SIR model once a node is cured after infection it becomes permanently immune,but we assume this immunity to be temporary. So we obtain an epidemic model with time delay on scale-free networks. Using the mean field theory the spreading threshold and the spreading dynamics is analyzed. Theoretical results indicate that the threshold is significantly dependent on the topology of scale-free networks and time delay. Numerical simulations confirmed the theoretical results.

Composite sandwich structures have been used more and more widely in the underwater structures, therefore deformation problems under deep-water hydrostatic pressure can not be ignored. For the deformation properties of composite sandwich structures under deep-water hydrostatic pressure, the paper carried out theoretical and test research. First, the paper analyzed the surface deformation features as well as the law of the element’s cross-sectional dimension, the core thickness and elastic modulus to the surface deformation by establishing theoretical analysis model; The results show that the deformation area can be divided into central area and boundary area, and the boundary effect is an important factor affecting the deformation, the core parameters can affect the reach of boundary effect. Second, the paper carried out hydrostatic test of composite sandwich structural element model, and then verified the theoretical analysis model’s rationality and accuracy by comparing the test results and theoretical results.

Considering geometric linearity and nonlinearity deformation form, the MSE and damping coefficient of the laminated composite cantilever plate were obtained with the elasticity theory based on the modal strain energy (MSE) method. The validity of the theory compute program was validated by the FEM program with the all layers 0° layup case. The longitudinal MSE of the plate at various lengths were investigated under the deformation form above. The damping coefficient of the laminated composite cantilever plate at various fiber orientations. The results are significant for sample fabricate of the laminated composite damping experiment.

When image with Gaussian white noise being de-noised by wavelet threshold, there are some problems such as blurring and the loss of details of edges of image. To solve above problems, image de-noising method based on wavelet transform and Wiener filtering is proposed in the paper, first using wavelet threshold to de-noise, and then using Wiener filter to smooth the image so as to get high image quality. Experimental results show that this algorithm on de-noising proposed not only can effectively suppress Gaussian white noise, but also can well preserve the details of image edges

Glucose dehydroabietate was synthesized from glucose and dehydroabietic acid in the presence of propanediol and base catalyst. The product exhibits good surface activity. Rosin is one kind of widely applied raw materials. The main components of rosin, resinolic acids, have hydrophobic phenanthrene structure. The acid group of resinolic acids can react with hydrophilic compounds to form a series of surfactants. Therefore, rosin can be used for surfactant production. Glucose is the most widely distributed and important monosaccharide. All plants can produce glucose via. photosynthesis. While glucose reacts with rosin, the product, glucose rosinate, exhibits excellent surface activity. Besides, just like sugar esters [1], the surfactant has the characteristic of non-toxic, easily degradable and harmless for environment. It can be applied widely in food and other industry. In the present paper, glucose dehydroabietate has been synthesized from dehydroabietic acid and glucose with propanediol as solvent. The optimum reaction conditions have been investigated.

In the paper a digital watermarking algorithm based on chaotic encryption and wavelet transform is proposed. It uses Arnold transform to encrypt the original watermark image, and then decomposes the original host image to different frequency sub-image, combining with the merits of transform domain watermarking algorithm. The encrypted watermark image is embedded into the low-frequency coefficients of image by wavelet transformation. Experimental results confirm that the algorithm has good robustness.

The equation to determine the neutral axis of concrete filled steel tube(CFST) component with round section is presented in this paper. The geometric equation, physical equation and static equilibrium equation of CFST are analyzed to determine its section neutral axis. The compressed mechanical properties of CFST component are analyzed with the concrete material properties divided into tension and compression parts.Comparing the numerical results with the experimental results it can be verified that the equation to determine the neutral axis of CFST component with round section is useful to solve the problems that the tension and compression material properties of concrete are different.

The droplet transition of electrical arc welding is a complicated process that combines heat, mass and momentum transfer. A high-speed camera system with laser in the background is established to observe the fast changing process of droplet transition. A group of high-speed camera pictures which indicate that the size and shape of droplet have strong uncertainty are taken and analyzed. The results show that the randomness of droplet size and shape are decided by its internal and external random factors, such as: the changing of the length of welding wire stretched out, the fluctuation of the feed speed of welding wire etc.

The droplet transition of electrical arc welding is a complicated process that combines heat, mass and momentum transfer. A high-speed camera system with laser in the background is established to observe the fast changing process of molten droplet transition. A group of high-speed camera pictures which indicate the droplet gravity center is unstable in welding metal transfer process are taken and analyzed. The experimental results show that the electromagnetic force is the unstable root of the droplet gravity center.

Thermal behaviors, compositions and structures of silver laurate prepared in wateralcohol system with double jet method has been investigated via DSC, FTIR, XRD and SEM, respectively. Silver nitrate, sodium hydroxide and lauric acid were used as reactants and PVP as protective agent. Results show that the highly ordered layer structures of as prepared samples were weakened at 173oC and 212oC and then decomposed at 238oC. The morphology changed from fiber-like to lamellar when the silver laurate was calcined at 212oC.

Machine Vision was used to observer and measure the underwater bubbles. There are several ways been taken to solve many difficulties in the process of the acquisition to get the image. Such as the equipment selection, the light sources selection, the approach to images and the feature extraction of the image. The most important of them is the noise elimination and the extraction of the bubbles. The feature of the image can be very obviously after the Median filter and Sub-pixel edge detection. In this way, it provided an effective and feasible method to measure the underwater bubbles.

PTG materials were prepared using TiO2 as photoconductors, silver palmitate as a reducible silver salt, PHZ as a toner and 2246 as a reducing agent in acrylic acid resin binder. The PTG material was coated onto the PET film and then exposed by UV-meter. Effects of the amount of TiO2 and PHZ on the image properties were investigated by means of ultraviolet-visible spectroscopy (UV) and transmission density meter. The formation of silver image was confirmed from the absorption peak around 430nm and X-ray photoelectron spectroscopy (XPS) analysis. The results show that the optimum content is that PHZ of 0.5g and titanium dioxide of 0.03g. The Atomic Force Microscopy (AFM) showed that the triangle-like grains with size of 43nm and height of 10nm grew uniformly on the surface of the exposed PTG film.

α-pinene was isomerized in the presence of phosphomolybdic acid. One of the products, α-terpinene, can react with maleic anhydride to form α-terpinene and maleic anhydride adduct (TMA). The optimum conditions for the synthesis of TMA have been investigated. The yield of 83% can be attained with the heterogeneous catalyst phosphomolybdic acid on active carbon (PMA/C), and can maintain ~67% after the catalyst was used for 5 times.