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A Method was studied for the determination of Al、Cu、Ni in Zr-based amorphous alloy by inductively coupled plasma atomic emission spectrometry (ICP-AES). Samples were dissolved by hydrochloric acid,nitric acid and hydrofluoric acid,analytical spectral lines for aluminum,copper,nickle are 308.215nm,327.396nm and 231.604nm.Interference of zinc was eliminated by the matrix-matching method, the experiments were done with optimized Operating Parameters. The correlation coefficients of the calibration curve are all 0.999,detection limits are 0.0010%,0.005% and 0.0006% respectively,and the range of recovery is 98%-104%.

In our study, a new kind of foam composite was prepared by melt blending with PVC as the matrix and carbon black (CB) as the filler, the standard-spline was made in the dumbbell system prototype. Tensile strength and elongation at break were measured at 25°C。When the CB was added greater than 2.0%, with the increase of CB added, the determination of sample mechanical index began to decline, when the CB content was greater than 9%, tensile strength and elongation at break of the composites remained basically unchanged.

In our study, a new kind of material was prepared by melt blending with PVC as the matrix and carbon black (CB) as the filler. With the amount of CB increasing, the notched impact strength of composite increased greatly, however the tensile strength declined. When the amount of CB was 30%, the notched impact strength of composite was 9.66 KJ/m2, the tensile strength dropped from 48.3MPa to 33.2MPa. The distribution of CB in the PVC matrix is relatively uniform and no large agglomeration in the PVC matrix.

Traditionally, spiral case structure is classified as non-member bar reinforced concrete structure. It is improper to calculate reinforcement area according to the area of tensile stress figure, which often causes a lot of waste of reinforcement; it is particularly true for the spiral case structure with steel liner. In combination with the practice of a spiral case of the hydropower station, the different schemes are proposed by 3-D nonlinear FEM software ABAQUS to study the feasibility of thinning steel liner in this paper. It is indicated that magnitude of steel liner and the hoop reinforcement stress is of no obviously increasement, damaged region of concrete is of no significant variation and the cracking range of peripheral concrete is of the requirements when the rate of steel liner thinning is tiny. When the thinning rate is 10%, there is a significant increase in crack width, but it still can meet the requirements of the specification. Although the magnitude of the stresses is not beyond the strength requirement, the maximum cracking width of concrete is over the designed standards when the rate is up to 30%. In this case, the crack width is controlled by collocating the more reinforcement in local positions. It is concluded that steel liner thinning is reasonable and feasible; what’s more, the magnitude of thinning is very large when the more reinforcement are collocated without prejudice to construction. It can provide references for optimization of the steel liner for the similar projects.

In our study, a new kind of water treatment composite was prepared by melt blending and molding foaming, with synthetic rubber EPDM as the matrix, graphite oxide modified glass fiber (GF) as the filler. The foamed composite had a certain adsorption capacity of methylene blue dye in the water and toluene. With the increase of the graphite oxide modified GF, the composite on the methylene blue adsorption rate was increased, however, for toluene, the rate of adsorption was reduced. Due to restrictions on the oxidation of graphite and composite structures and the adsorption capacity of the material was limited.

In this study, a new composite was prepared for aniline adsorption by melt blending with EPDM as the matrix and natural zeolite was modified by microwave as the filler. The properties and some influential factors of composite for adsorption of aniline in the solutions were experimentally investigated, such as composite dosage, adsorption time and pH values. The results showed that in the case of the initial concentration of the aniline wastewater was 50mg/L, when the use level of composite was 1 g, pH value was 1, and the oscillating adsorption time was 2 h, the removal rate could be up to 92%.

The detection of pedestrian which has been widely used in digital surveillance systems is a popular topic in computer vision. This paper mainly discusses a system of pedestrian detection in video sequences captured from a stationary camera hanging in a public scene. We describe an efficient system combining background subtraction based on Gaussian Mixture Model (GMM) and object classification based on Histograms of Oriented Gradients (HOG). We first process moving objects segmentation using GMM. Then a HOG detector is used to classify the moving objects into person and none-person. Experimental results on video sequences have demonstrated that the real-time tracking system can process 15 to 30 frames per second robustly with a high accuracy.

In our study, a new kind of material for toluene adsorption was prepared by melt blending with EPDM as the matrix and waste dusty slag as the filler. The effects of dicumylperoxide (DCP) and waste dusty slag contents on the toluene absorbency were studied. The results show that the toluene absorbency reaches the highest value 388.11 % for the composite with 2 wt % DCP and 30 wt % waste dusty slag. Comparing the toluene absorbency for three samples, the experimental result indicates that the toluene absorbency of waste dusty slag /EPDM composite was higher than that of EPDM (crosslinked) and EPDM

In our study, a new kind of material for Copper (Cu2+) absorbency was prepared by melt blending with EPDM as the matrix and modified zeolite as the filler. In order to overcome this obstruction, PEG-2000 was used as pore forming agent. By calculating, trial parameter n was 1.9, so, the composite was easy absorption. By SEM and XRD measurement, it was confirmed that the composite was more suitable as filler than the original zeolite and the acid modified zeolite. It can be showed that the pore forming agent adding was necessary and effective for the absorption by SEM micrograph of suction passage in EPDM and the composite.

In our study, a new kind of material for oil adsorption was prepared by melt blending with EPDM as the matrix and roasting Fe2O3as the filler. The effects of dicumylperoxide (DCP) and roasting Fe2O3contents on the oil absorbency were studied. The results show that the oil absorbency reaches the highest value for the roasting Fe2O3/EPDM composite with 2 wt % DCP and 30 wt % roasting Fe2O3. Comparing the oil absorbency for three samples, the experimental result indicates that the oil absorbency of roasting Fe2O3/EPDM composite is higher than that of EPDM (crosslinked) and EPDM.

In order to comprehend the salinity transport mechanism,the tidally varying circulation,and salt stratification are investigated in Lingdingyang bay.The conclusions are:When the discharge is moderate,Lingdingyang is a highly stratified estuary,and salt wedge movement is very prominent.The baroclinic circulation is comparatively strong,and strong salinity gradients create a complex three-dimensional flow.A tidal intrusion front moves upstream in flood periods,and distance of movement is longest in flood slack.Because Velocity shear across the interface of fresh and salt water,and intense waves from and break,entrainment is very strong which cause salt water into freshwater.

In our study, a new kind of material for Cr6+ absorbency was prepared by melt blending with EPDM as the matrix and modified zeolite as the filler. Contrast between natural zeolite, acid modified zeolite and modified zeolite / EPDM composite on equilibrium adsorption amount (Q), the results showed that the Q of composite were far greater than that of natural zeolite and acid modified zeolite.

Liuzhou is an important city of flood protection in china.Flood protection assessment for any new relational-water project is prerequisite.In order to understand the impact to river flow,a 2-D hydrodynamic model is set up,and use ADI method to solute partial differential groups.The results can be shown as fellows: Computation is fast steady and convergent by ADI method,and associated errors of model control is satisfied.The bridge pier has major impacts on river flow.Velocity change due to bridge built could lead to riverbed erosion between piers,and siltation along the upstream and downstream of the Weiyi bridge.Water level could be rised in the bridge upstream with the raised water level of about 0.08m,which might affect drained floods to a some degree.

In combination with the practice of a pumped storage hydropower station, a 3-D nonlinear finite element method on the preloading filling spiral case is carried out to compare and analyze stresses of the steel spiral case and hoop reinforcement, the stress and bearing ratio of the surrounding concrete, the contact state between the spiral case and concrete in different precast water head. The results indicate that the stress of the surrounding concrete will get better with the increasing of precast water head. But there is a distance between the spiral case and the surrounding concrete when the water head is excessive, which is unhelpful for operating of the unit. When the precast water head of the spiral case is 439m or so, it can play a greater degree of mechanical characteristics of steel and concrete under the premise of operating stably of the unit.

In our study, a new kind of material for oil adsorption was prepared by melt blending with EPDM as the matrix and roasting Fe2O3as the filler. By considering the influence of pH, temperature, stirring speed on adsorption capacity. The results showed that the environmental pH has little effect on the crude oil absorbency of the composite; “Room temperature” is the optimum temperature; increased the stirring speed can reduce the adsorption time.

In our study, a new kind of material for toluene adsorption was prepared by melt blending with EPDM as the matrix and waste dusty slag as the filler. By considering the influence of pH, temperature, stirring speed on adsorption capacity. The results showed that the environmental pH has little effect on the toluene absorbency of the composite; “Room temperature” is the optimum temperature; increased the stirring speed can reduce the adsorption time.