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Dynamic fracture of explosion containment vessels subjected to internal blast loads is the foundation for conducting safety assessment and failure analysis of explosion containment vessels. The experiments were carried out to investigate dynamic fracture characteristics of cylindrical steel shells subjected to internal blast loadings at the centers. The elastic-plastic response of cylindrical steel shells was conducted using nonlinear dynamic finite element analysis code LS-DYNA. The fracture mode and fracture mechanism of a cylindrical shell were specially studied through analysis of deformation， macrographs of fracture surface and elastic-plastic response. The results show that dynamical ductility deformations appear and the shear bands form when the cylindrical steel shell expands under internal blast loading. The cylindrical steel shell fractures preferentially along the shear bands due to its softening effect. The fracture mechanism is that the shear bands tear under tensile circumferential stress. The shear bands and the tensile circumferential stress dominate the final fracture mode. The fracture mode is of the ductile fracture.

Broken rules of cylindrical steel shell subjected to internal blast loads is the foundation for conducting safety assessment and failure analysis of explosion containment vessels. The experiments were carried out broken rules of the cylindrical steel shells subjected to internal blast loadings at the centers. The elastic-plastic response of cylindrical steel shells was conducted using nonlinear dynamic finite element analysis code LS-DYNA. The results show that the deformation was’t a discrepancy in the explosion center of the cylindrical steel shell in same space, and the deformation descended slower along with thickness augmentation in the end of explosion center. The radial stress、hoop stress and axial stress was a discrepancy in the thickness way of cylindrical steel shell of explosion center The most leading cause of destructivity of cylindrical steel shell was that inner wall bearing normal stress and exterior wall bearing tensile stress; the hoop stress was broken more than axial stress cylindrical steel shell. The whole process was presenting hoop fractured and axial growth.

Through the methods of questionnaire survey, the literature and experts interviewing, paper analyses the current situation of sports events on the campus in our country. Because of the inadequate understanding of the economic benefits of basketball games on the campus for the sponsors and the organizers of the sports event, the evaluation system of economic benefit of the sports event is established based on the basic principle of economics in the paper.

Based on the theory and method of energy analysis originated by H.T.Odum, the typical wetland of Qinghai Lake was studied. With the method of energy analysis, the value of renewable energy was estimated at 1.96×1022 sej, with a monetary value of $2.45×108. The energy value of capital input/output was 1.87×1022 sej, with a monetary value of $2.32×108.The energy value of waterfowls was 1.10×1024 sej, with a monetary value of $1.37×1010. The energy value of aquatic product was 2.94×1023 sej, with a monetary value of $3.66×109. It is clear that the total energy value of waterfowls and aquatic products exceeded 90%, the highest in the entire ecological system of Qinghai Lake wetland. The result indicated that emphasis should be placed on protection of waterfowl and fish resources of Qinghai Lake under the condition of effective protection and rational utilization of the values of ecological service of Qinghai Lake wetland. Furthermore, intensified development of ecological tourism and strengthened scientific research should be a key direction in future.

Resistance strain gauge is common used in strain measurement, particularly in small elastic strain measurement, it has many advantages. However when the measured strain increases, the output nonlinearity of the Wheatstone bridge will become obvious; in this paper the nonlinearity error of the output in large-strain measurement is analyzed, and based on this a mathematical algorithm for nonlinearity compensation is proposed; finally the effect of the algorithm for nonlinearity compensation is proved by theoretical research and experimental treatment.

A catalyst comprising SO42–/ZrO2superacid was prepared by impregnation and characterized by FT-IR, XRD, and BET. A novel procedure for oxidative desulfurization of simulated light fuel oil using K2FeO4over the SO42–/ZrO2solid superacid was developed. The effects of the oxidantion and extraction conditions on desulfurization were investigated. At temperature of 30 °C, SZ of 0.2 g, K2FeO4of 0.2 g, reaction time of 1 h, 20 mL of oil is oxidized, followed by methanol extraction at 15 °C for 10 min with the volume ratio of solvent/oil of 1, the results display desulfurization rate for simulated light fuel oil and straight-run gasoline were 88.2% and 89.2%, respectively.

The effect of Ce2O3 on the fabrication of the Al-Ti-C-RE refiner prepared by adding a powder mixture of potassium titanium fluoride and carbon into the aluminum melt was studied by means of the OM, XRD, ESEM and EDAX etc. It found that the addition of Ce2O3 increases the reaction rate between the potassium titanium fluoride and carbon during the fabrication of the Al-Ti-C-RE refiner making the Al3Ti and TiC phases well distributed. Moreover, the Ce2O3 is an intensive kind of the surface activation element strongly sticking to the Al3Ti phase after reacting on the master alloy observed by ESEM, which formed a new rare earth compound phase [AlTiCe] and accelerated the synthesis rate of TiC particles. And adding 0.15wt% Al-Ti-C-RE alloy can refine the pure Al strongly and remarkably, in which the grain size of pure Al is lower than 94.2μm. When the holding time of refining exceeded the 120 minutes, the refining effect on the pure Al has not faded remarkably, which proves the Al-Ti-C-RE prepared by the Ce2O3 have long-life and stable refining effects.

The Key of Web Services lies in how to describe and find Web serve, and which is mainly realized depending on UDDI technology is realized. The company which provided the services by UDDI can register information, it can make the potential user and/or cooperative partner find the services and simple shelf of the business of these companies. At the same time, UDDI can make company find other company, so as to expand the potential business partnership. We can say UDDI has offered the chance for company to step into new market and service, also make the companies in all scales expand their own place business among the global market rapidly.

The Al-20%Si alloy was prepared by mixing the high temperature melt of hypereutectic Al-30%Si alloy with the pre-crystallized low temperature hypoeutectic Al-10%Si alloy melt and then superheating the mixture, i.e., melts mixing and superheating (for short: MMS), combining with chemical metamorphism. The effect of pre-crystallized characteristic of the mixed melt on microstructure of Al-20%Si alloy was then investigated, The primary Si granules of the sample, poured by melt mixing with different composition and temperature, were well distributed with a grain size of less than 36μm. And after superheating, the primary Si phase of the mixed melt could be further refined and distributed more uniformly, which if adding the modificator into the mixed melt, the size of primary Si were been deceased and refined by less than 20μm. The analysis result shows that the decrease in the temperature of the mixed melt, from the average temperature of 740 °C for the mixture of Al-30%Si (900°C) and Al-10%Si (580°C) to 670°C for present alloy, leads to the increase in the degree of undercooling, and consequently to the refinement of primary Si. During the superheating, the growth, local melting, as well as the proliferation of primary Si occurred because of the unhomogeneous micro-distribution of the temperature and composition within the mixing melt, resulting in the further decrease in the grain size of primary Si. And adding the modificator could promote the effect of modification of primary Si of MMS process on the hypereutectic Al-Si alloy.

With the rapid development of the Internet and information, communication technology, human society began to enter into the intelligence community with the digital and network platform. With the popularization of computer application in schools, enterprises and other institutions, the meetings of governments, enterprises and institutions has broken the traditional model that the meetings are held in the same place and at the same time, and network meetings is to be popularized with the increasingly fast paces. But regardless of the company or the university, there exists the problems of meeting management. Now the overwhelming majority of the conference management is still in a state of manual, inefficient and prone to error, not manageable, not rule out any untrue phenomenon. Therefore, the internal management, self-improvement of the meeting management can not be ignored. This paper aims to resolve this problem by designing a meeting management website. Conference Management website ASP can be used to design the conference management website, ASP (Active Server Pages) dynamic website is a technology which is introduced by Microsoft Company to replace CGI (Common Gateway Interface)-a common Gateway Interface. By combining the knowledge of ASP HTML language, ASP directives and ActiveX components and Access database, the paper uses the own Web server to create and run a dynamic interactive Website 。The paper aims to realize the work of meeting managing, application, auditing, controlling, minutes of meetings processing through the meeting management website.

A series of layered-structure Bi-based oxychlorides such as BiOCl, Bi3O4Cl, Na0.5Bi1.5O2Cl, Bi4NbO8Cl and MBiO2Cl (M = Ca, Sr, Ba, Cd, Pb) used as efficient photocatalysts. Among them, Bi3O4Cl (Eg = 2.79 eV), Na0.5Bi1.5O2Cl (Eg = 3.03 eV), Bi4NbO8Cl (Eg = 2.38 eV) and PbBiO2Cl (Eg = 2.45 eV) are visible-light-responsive. The powders synthesized by solid state reactions were characterized by X-ray diffraction (XRD) and UV-Vis diffuse reflection spectrum. Their photocatalytic activities were evaluated by the degradation of methyl orange. The results generally show that the UV-induced photocatalytic performances of the novel oxychloride catalysts are better than or comparable to that of anatase TiO2. The high photocatalytic performance of Bi-based oxychlorides is mainly ascribed to the presence of strong internal static electric fields between layers.

Eu-doped CaS phosphors were prepared from sulfurization of CaCO3 in H2S gas without flux. The doping of Eu activator was conducted in two different modes: synchronous doping during sulfurization of CaCO3 and subsequent doping by vacuumly calcinning pure CaS and Eu2O3. Comparison of the as-prepared samples indicated that subsequent doping led to larger optimum Eu concentration and lower red emission intensity than synchronous doping. The different luminescence properties are ascribed to the different activator distributions in CaS host induced by different doping modes, and the uniform distribution resulted from synchronous doping is beneficial to the luminescence of the phosphor.