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161.
国家粮储库屋面防水APP卷材施工技术 总被引:1,自引:0,他引:1
针对国家粮食储备库的特点,就屋面防水APP卷材热熔法施工的施工准备及工艺流程进行了介绍,提出了具体的施工技术要点及质量通病的防治措施,取得了良好的施工效果。 相似文献
162.
Jinsheng Que Qing Wang Jianping Chen Bingfei Shi Qinghui Meng 《Bulletin of Engineering Geology and the Environment》2008,67(4):479-483
The paper describes some geotechnical properties of the soft soils in Guangzhou College City, China, which are difficult to
both sample and test. Laboratory and in situ tests were carried out to assess the physical and mechanical indices of the soils.
The data were statistically analyzed and linear regression undertaken such that equations could be developed by which the
geotechnical properties of the soft soils can be predicted. The statistical validity of the degree of correlation confirmed
that using these equations, the mechanical indices can be estimated from physical indices determined by routine testing.
相似文献
163.
A new efficient numerical method and the dynamic analysis of composite laminates with piezoelectric layers 总被引:1,自引:0,他引:1
Firstly, a numerical method for the inversion of Laplace transform is developed and its accuracy is shown through examples. Then, a state-vector equation for the dynamic problems of piezoelectric plates is deduced directly from a modified mixed variational principle for piezoelectric bodies and its exact solution for the dynamic problems of simply supported rectangle piezoelectric plate is simply given. For multilayered hybrid plates, we derive the solution in terms of the propagator matrices. The techniques accounts for the compatibility of generalized displacements and generalized stresses on the interface both the elastic layers and piezoelectric layers, and the transverse shear deformation and the rotary inertia of laminate are also considered in the global algebraic equation of structure. Meanwhile, there is no restriction on the thickness and the number of layers. As an application of the numerical inversion of Laplace transform presented in this paper, typical numerical examples of the harmonic vibration and transient response are proposed and discussed. Since the highly accurate numerical results, they can serve as benchmarks to test various thick plate theories and various numerical methods, such as the finite and boundary element methods for transient response problems. 相似文献
164.
文章从对中国江南古典园林中重要的一支——徽派园林的现状分析出发,提出了对徽派园林保护和利用的方向和策略,阐述了对徽派园林加以继承和创新的意义和方法。 相似文献
165.
Associations (dimer or aggregate) of anthracene (An) fluorophores tend to interrupt the monomer emission and reduce the quantum yield (ΦPL); therefore, poly(methyl methacrylate) (PMMA) chain was used in this study to chemically link to anthracene and to block the mutual associations among the anthracene fluorophores. With this aim, the target polymers were prepared by anionic polymerizations with 9,10‐dibromoanthracene/s‐butyllithium as initiating system to proceed polymerizations of methyl methacrylate (MMA) directly or in the presence of 1,1‐diphenylethylene (DPE). Use of DPE before addition of MMA produces stable initiating anionic species and avoids potential side reactions during polymerization; however, it also introduces four β‐phenylene rings around the central anthracene ring, which interfere with the corresponding emission pattern and reduce the ΦPL (32%) value due to potential interactions between phenylene rings and anthracene. On the contrast, polymerization without participation of DPE results in polymer with central anthracene ring directly connected to two PMMA chains, which gives clean vibronic emission pattern with limited association emissions and enhanced ΦPL (52%) value. Physical blending of anthracene by PMMA is less efficient to restrain the associations and results in a film of lower ΦPL (20%). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
166.
T. Jeevananda Siddaramaiah Taek Su Lee Joong Hee Lee O. M. Samir R. Somashekar 《应用聚合物科学杂志》2008,109(1):200-210
Polyaniline/carboxylated multi-walled carbon nanotube (PAni/c-MWNT) nanocomposites have been synthesized by micellar aided emulsion polymerization with various c-MWNTs compositions, viz., 0.5, 1, 5, and 10 wt %. The microcrystalline parameters such as the nanocrystal size (〈N〉), lattice strain (g), interplanar distance (dhkl), width of the crystallite size distribution, surface weighted crystal size (Ds), and volume of the ordered regions were calculated from the X-ray data by using two mathematical models, namely the Exponential distribution and Reinhold distribution methods. The effects of heat ageing on the microcrystalline parameters of the PAni/c-MWNT nanocomposites were also studied and the results are correlated. The thermal stability and electrical resistivity of the PAni/c-MWNT nanocomposites were examined with thermogravimetric analysis (TGA) and a conventional two-probe method. The TGA data indicate that the thermal stability of the nanocomposites improved after the incorporation of c-MWNTs. The influence of temperature on the resistivity of the nanocomposites was also measured. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
167.
The collagen-chitosan complex nanofibers have been prepared for the first time by electrospinning. The mixed HFP/TFA (the volume ratio of 90/10) was found to be the appropriate solvent for electrospinning. The concentration of the spinning solution and the ratio of chitosan/collagen were varied and adjusted to get smooth nanofibers. It was found that the diameter of the spun fibers became thick with the concentration of the solution increasing and became fine with the ratio of the chitosan/collagen increasing. We have characterised the molecular interactions in collagen-chitosan complex by Fourier transform infrared spectroscopy. The spun fibers are designed to mimic the native extracellular matrix for tissue engineering and to develop functional biomaterials. 相似文献
168.
169.
复杂连通区域扫描线填充算法的问题及改进 总被引:1,自引:0,他引:1
针对复杂连通区域扫描线填充算法可能出现的重复填充错误,分析了产生错误的原因,并给出了相应的改进办法.从而实现了复杂连通区域的快速正确填充。 相似文献
170.
Kurian A.P. Puthusserypady S. Su Myat Htut 《Wireless Communications, IEEE Transactions on》2005,4(3):984-989
In this paper, a novel direct sequence/spread spectrum (DS/SS) communication system is proposed. This scheme exploits the two-dimensional complex valued chaotic Ikeda map as the spreading sequences. With this double spreading DS/SS system, the effect of multiple access interference can be mitigated by choosing the spreading sequences with appropriate cross-correlation properties. The performance of the system is assessed and demonstrated in a multiuser environment by means of computer simulation with additive white Gaussian noise, Rayleigh fading, and selective fading channel conditions. These studies reveal that the proposed system significantly outperforms the Gold code DS/SS-BPSK system in synchronous channel conditions. In asynchronous case, the improvement is substantial for low signal-to-noise ratios. 相似文献