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It’s important to study the vibration characteristic of submarine pipelines under current for reducing the harmful vibration. Research on fluid-structure interaction of submarine pipeline under current was presented. The pressure and velocity distribution of flow field around pipe with different velocity of flow were studied by ANSYS finite element software. The results show that the pipe is under the action of drag force along the direction of flow. The drag force increases with the flow velocity.

Coal seam floor contours are one of the most important 8 mine maps, and was usually used for coal mine decision-making. However, the graph, which was expressed as lines, has many disadvantages, including inadequate intuitive, poor visibility, and weak in expression of three-dimensional morphology formation. Thus, the readers have to spend more time to reveal the spatial distribution of coal deposits. According to the coal seam floors contours, and considering the constraints of faults in coal seams, the following steps were implemented to acquire coal seam floor DEM, which are: 1) contours discrete; and 2) interpolation using Inverse Distance Weighted method (IDW). The process was easy-manipulated, and the results could reflect the spatial distribution of coal seams in an objective, intuitively, and strong visibility manner. The method could facilitate and guide the analysis of mine design and coal production.

In this study, 7050 aluminum alloy strip was produced using the twin-roll casting technique. Microstructures and properties of the cast-rolling 7050 aluminum alloy were investigated by means of optical microscope (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Vickers hardness test. The results indicate that microstructures of cast-rolling 7050 alloy strip are inhomogeneous on the cross section. From the edge to the center, the size of grain decreases gradually and becomes more homogeneous, showing a transition from dendrite grains to equiaxed grains. There are undissolved second phase particles in grains and at grain boundaries. And the dendrite grains and second phase particles can be reduced by solution treatment, and the hardness of the cast-rolling strip can be improved by aging treatment.

This paper describes the history and development of botanical pesticides, analyze the active ingredients of plant pesticide and the application in pest control and with the work practice make ​​a proper study on the future development of botanical pesticides, in order to promote the development of botanical pesticides, developed more and better economic, efficient and pollution-free new pesticides, the benefit of mankind.

In this paper, one-dimensional heat conduction equations is studied, many difference Schemes have been proposed to solve it. In order to find a high accuracy difference scheme in all the methods, we give a numerical experimentation in this paper. by numerical experimentation, a high accuracy difference scheme for solving Heat conduction equations initial boundary value problem is found, according to the truncation error and stability analysis ,we find its accuracy is better-then- third-order in time and space direction. this is a valuable method and better then the others this is a high accuracy difference Scheme. this scheme is a valuable method in Heat conduction and Fluid mechanics.

The dynamic response of underwater structures is different from those in air because of interaction between fluid and solid. The influence of water depth on dynamic effect of the pier is studied base on a cable-stayed bridge in deep water. The girder of the cable-stayed bridge is simplified as a lumped mass on the top of the pier. The three-dimensional finite element models of pier with different water levels are built to calculate the dynamic characteristics and dynamic response of the pier under the action of harmonic load. The calculated results show that with the rise of water level, the nature frequencies of the pier decrease while the displacement and stress increase.

The purpose of this paper was to evaluate the capacity of anion ion exchange fiber to uptake the heavy metal(Co2+、Cu2+、Zn2+、Cd2+、Pb2+、Ag+) from the water. A new polyamine-type ion exchange fiber(IEF) based on polyacrylonitrile (PAN) with higher exchange capacities was prepared by crosslinking through hydrazine hydrate, followed reacting with diethylene triamine. FT-IR analysis indicated that amine, imido, acylamino and carboxyl groups were introduced into PAN fiber through the surface modified reaction of cross linking and amination. The structures of the IEF were characterized by means of SEM. The results showed that the surface of fiber became rougher and thicker and more heterogeneous. The static and dynamic adsorption experiments demonstrated the high selective adsorption property of the IEF for Ag+ and Cu2+. Furthermore, the adsorption mechanism for the metal ions with IEF was investigated with the FT-IR spectra studies.

This paper points out the difficulties because of the direct measurement of elasticity coefficients of brittle materials, presents the composite measurement method, and describes the data processing procedure. A new method is introduced which is more precise for measuring the elasticity coefficients, and C program is compiled on the basis of the method.

The area of web-based CAD system has grown since the mid-1990s. This paper introduces a new web-based CAD system for fabric appearance. The system uses the Browser/Server structure, and the designer can employ this system installed on the server to build a 3D model of fabric appearance through the Web browser. The basic architecture is discussed in this paper. Some key technologies, such as graphics display, texture mapping and the data exchange, are also investigated. In the last, some future research directions are presented.