Advanced Materials Research Vols. 424-425

Abstract: The floating of floor due to insufficient anti-floating of floor happens occasionally in the design and construction process of basement parking garages. In this paper, the causes of insufficient anti-floating of basement parking garage floor are analyzed combined with engineering examples.

Abstract: Rational spatial distribution plays a significant role on fire safety of subway station. The location of ticket machine is one of the main factors affecting fire feature of such stations. Taking a certain subway station as a physical model, this paper carries out simulation analysis on several fire scenarios with the help of software FDS. By comparing the fire temperature, smoke density as well as visibility under different kinds of space between ticket machine and the escape exit, the appropriate space between ticket machine and escape exit is obtained which could be a reference for practical projects

Abstract: In this study, the natural polymeric sesbania gum was modified and used as a new size for the sizing of polyester/cotton yarn (T/C yarn). Oxidative degradation of sesbania gum was carried out by using sodium hypochlorite(NaClO), resulting in chain segment with relative smaller molecular weight, then short-chain vinyl acetate was grafted onto the polymer chain of sesbania gum. The modified sesbania gum was used for sizing T/C yarn. The viscosity, thermostability of modified sesbania gum, and the breaking strength, index of hairiness, wear-resisting property of sized yarn was characterized and discussed.

Abstract: Nowadays urban subway transport system has transformed its role from auxiliary facilities of urban traffic into a key component in people's lives. It is imperative to promote fire safety level of subway system. This paper simulates the crowd evacuation of the subway train fire. Four passenger densities within the train are set and the results of the software simulation with the calculation results based on specification are compared. It is relatively reliable to reflect the influence of the passenger density on the crowd evacuation, and some suggestions are also given out

Abstract: In this study, nanotubular materials multi-walled carbon nanotubes (MWCNTs) were used to encapsulate a model drug, doxorubicine hydrochloride (DOX). Then, the drug-loaded nanotubes (DOX/CNTs) with an optimized drug encapsulation percentage were mixed with poly (lactide-co-glycolide) (PLGA) polymer solution for subsequent electrospinning to form drug-loaded composite nanofibrous mats. The morphology was characterized using scanning electron microscopy (SEM). The proliferation of mouse fibroblast cells cultured on both PLGA and CNTs-doped PLGA fibrous scaffolds were compared through 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide (MTT) assay of cell viability and SEM observation of cell morphology. In vitro drug release behavior was examined using UV-vis spectroscopy. We show that the incorporation of CNTs and DOX/CNTs within the nanofibrous mats does not significantly change the morphology of the mats. In addition, our results indicate that this double-container drug delivery system (both PLGA polymer and CNTs are drug carriers) is beneficial to avoid the burst release of the drug. The drug loaded elctrospinning composite nanofibrous mats developed in this study may find various applications in tissues engineering and pharmaceutical sciences.

Abstract: Taking a subway tunnel as the research object and based on the CFD simulation method, this paper adopts a large eddy simulation analysis software FDS to simulate and analyze the effect of exhaust velocity on fire smoke control under the condition of the same longitudinal ventilation velocity in subway tunnel. The simulated results can provide some reference to design institutes in the selection of exhaust fan. While the longitudinal ventilation velocity set as 1m/s, the simulation results demonstrate that a quite good smoke control effect could be achieved when the exhaust velocity reaches 5 m/s in the smoke exhaust duct

Abstract: There are changes in material properties of concrete when compared axially loaded short columns with micro-expansive concrete filled steel tube with axially loaded short columns with common reinforced concrete and these changes will inevitably lead to the change of axially loaded short columns with micro-expansive concrete filled steel tube in performance. It is impossible to fully use the existing research results of axially loaded short columns with common reinforced concrete; therefore, it is necessary to do experimental research on the working performance of axially loaded short columns with micro-expansive concrete filled steel tube. This paper studied the hydration heat, self-stress and failure load according to the test conditions of the 15 axially loaded short columns with micro-expansive concrete filled steel tube specimen; determined the optimum mix amount of axially loaded short columns with micro-expansive concrete filled steel tube and proposed the increase rate of ultimate failure load of axially loaded short columns with micro-expansive concrete filled steel tube compared with axially loaded short columns with common reinforced concrete. This will facilitate the practical application of engineering.

Abstract: The SLS (Selective Laser Sintering, SLS) technology can directly manufacturing any complex structure, however, due to the limitation of the manufacturing engineering factor, the surface quality and the dimension accuracy of the green part are still an outstanding problem. So, the experimental methods were adopted to study the effect of part orientation on the machining accuracy, the part orientation will significantly affects the outline of the part due to the stair-stepping phenomenon, and then affects the surface quality and the dimension accuracy. The experimental samples of different part orientations including 0, 20, 45, 60, 90 degree were fabricated, and the results indicated that the stair-stepping phenomenon significantly affected by the part orientation, when the part orientation is 0, 45 and 90 degree, the dimension accuracy is best than other part orientation, it mean the stair-stepping phenomenon is smallest. So, when the part structure is complicated, the important structure dimension should be chosen the orientation 0, 45, or 90 degree

Abstract: Based on S195 diesel engine, the cylinder pressure of different methanol and diesel micro-emulsion were mea sured, and Chemical Kinetic was analyzed. The result showed that the max combustion pressure was added and the heat release was reduced by the methanol increase. The reason was that the different methanol content could effect the combustion process product such as CH2O，H2O2，O，OH，H, and effect ignition delay period and combustion duration period, and accordingly effect power and emission.

Abstract: The advantages of wavelet packets and their promising featu-res in various application have attracted a lot of interest and effort in recent years. In this paper, we propose the notion of quarternary small function wraps according to a quantity matrix dilation, which are gener-alization of univariate wavelet wraps. A nice procedure for designing the vector-valued quarternary small-wave wraps is provided. Their cha-racteristics are researched by virtue of time-frequency analysis method, wavelet transform and curvelet coefficients. The orthogonality formulas concerning these small-wave wraps are established. Furthermore, it is shown how to draw new orthogonal bases of space from the small-wave wraps. A method for designing a class of affine quarternary dual frames in four-dimensional space is presented. The results we obtain gains much improvement