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991.
Zhiyue Han Jingchang Zhang Xiuying Yang Hong Zhu Weiliang Cao 《Synthetic Metals》2010,160(19-20):2167-2174
Titanium dioxide and ferric oxide were prepared by the supercritical fluid drying (SCFD) method. A conducting polymer composite, poly(3-octylthiophene)/titanium dioxide/ferric oxide (POT/TiO2/Fe2O3) was first synthesized by chemical method. Transmission electron microscope (TEM) and scanning electron microscope (SEM) depicted the morphology of the samples, defining that TiO2 and Fe2O3 were successfully coated by poly(3-octylthiophene) molecules. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) showed the chemical interaction between poly(3-octylthiophene) and inorganic compounds in the composite. Cyclic voltammetry (CV) curves showed that the forbidden band gap of the POT/TiO2/Fe2O3 composite is 0.691 eV, realizing the complementary advantages of n and p semiconductor. UV–vis spectra (UV) and fluorescence spectra (PL) showed that its optical performance is far superior to poly(3-octyl thiophene), titanium dioxide and ferric oxide separately. Solar cell was sensitized by POT/TiO2/Fe2O3. A solar-to-electric energy conversion efficiency of 0.499% was attained with the system. 相似文献
992.
Jigang Wang Yongsheng Wang Dawei He Zhiyong Liu Hongpeng Wu Haiteng Wang Yu Zhao Hui Zhang Bingyang Yang 《Synthetic Metals》2010,160(23-24):2494-2500
Characterization of a solution-processable functionalized graphene oxide (SPFGraphene oxide) was investigated by FT-IR spectroscopy and the result of elemental analysis showed that the isocyanate treatment results in the functionalization groups in SPFGraphene oxide. Doping SPFGraphene oxide to P3HT based solar cells induces absorbing spectra more strongly and a great quenching of the photoluminescence of the P3HT. With an increase in the SPFGraphene oxide content, the overall performances of the hybrid devices increases first, reaching the peak efficiency for the 10 wt% SPFGraphene oxide content, and then decreases. After annealing at 160 °C for different time durations, the device containing 10 wt% of SPFGraphene oxide for 10 min shows the best performance with a power conversion efficiency of 1.046%, an open-circuit voltage of 0.73 V, a short-circuit current density of 3.98 mA cm?2 and a fill factor of 0.36 under simulated AM1.5G conditions at 100 mW cm?2; The similar content one for 20 min shows η value of 1.013%, which is lower than the former one to a small extent for longer annealing duration. The graphene has the potential to act as the next-generation material in the photovoltaic devices and other applications for ease of preparation, low price, large surface area, high conductivity and excellent transparency. 相似文献
993.
重力式纤维束滤池与均粒滤池的对比性平行生产试验表明,纤维束滤池处理效果理想,其滤料使用周期长、截污能力强、滤速高,生产效益显著。同时通过大量实验,对重力式纤维束滤池的除浊结果进行了公式拟合,并通过测试证明其误差0.5%。利用该数学模型可以对除浊结果进行很好的预测与分析。 相似文献
994.
目的针对市场里的旅游服务平台形形色色,良莠不齐现状造成的功能定位模糊、可用率低、基础用户少、难以形成用户黏度较高的平台健康可持续发展模式等问题,藉由网络微社区角度进行文化旅游服务平台的设计研究探索。方法通过案例分析法、比较分析法收集、整理、分析现有的旅游服务平台设计模式,发现问题,再用POEMO框架进行文化旅游服务平台功能模块的方案设计,并探索UGC模式对服务平台的创新个性化服务模块的正向影响,最终提取优选方案。结论设计了文化旅游服务平台构建的框架,阐述了服务平台建设的主要内容、采用的途径和具有的个性化定制服务,在网络微社区的影响下,将数字技术与文化旅游服务平台设计相结合,为相关服务平台构建提供借鉴和参考。 相似文献
995.
Yang Zhiyuan 《兵工学报》1989,10(3):2
本文探求了属于微分方程边值问题的直射弹道公式,以形简、意明、精确度高、研究方法的多样性和事物规律的不同表现形式为特征。在直射弹道的定义和数学描述之后,先从它的微分方程出发推导出了公式;再从方程的数字解出发探寻并确立了其规律性。 相似文献
996.
997.
在对邯郸传统村落与民居进行研究的基础上,发现了保存完整的天地庙,从文化的角度对其进行了分析,使我们对天地庙的有更深的理解。 相似文献
998.
999.
Cheng-Xiang Yang Yong Hong Wu Tung Hon 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2010,25(3):279-289
In this paper, we present a no-tension elastic–plastic model and an optimized back-analysis technique for stability analysis of underground tunnels. A set of constitutive equations is presented to simulate the no-tension behavior and plastic yielding of jointed rock masses which yield according to the Drucker–Prager yield criterion and permits no-tension. A nonlinear 2-D finite element model is consequently formulated for the prediction of the behavior of the excavated rock mass. As for the model parameters, the genetic algorithm technique is employed to find the optimal rock mass properties by minimizing the discrepancy between the predicted results and field measurement. The nonlinear finite element model coupling with the genetic algorithm optimized back-analysis technique is then applied to a synthetic example of a deep tunnel in yielding rock. The results show that the forward and back-analysis system is capable of estimating the model parameters with stable and good convergence and give reasonable predictions. Numerical experiments are also carried out to check the influences of position and numbers of measurements to the reliability of the back-analysis results. Furthermore, the sensitivity analysis of the genetic algorithms optimization procedure is discussed in terms of identification of geo-material properties. 相似文献
1000.