赤壁市长江取水工程取水设计

针对该项目需要从长江长期取到合格原水,且需要保证取水泵房结构稳定、施工方案成熟经济的工程目标,文章调研了湖北境内江河取水工程的设计,在满足功能需求的基础上,对结构形式、施工便利性及经济性作多方比选,最终确定在赤壁山矶头上游1.20 km处设置固定式取水头部、采用自流式引水钢管、圆形沉井取水泵房内设离心泵的建设方案。工程方案科学合理、结构稳定、施工周期短、取水稳定,可为类似取水工程的设计提供参考。     

冷历史对PA1010及其共混物内耗行为的影响

本工作对尼龙1010(PA1010)及其与双酚A型聚碳酸酯(PC)的共混物进行了内耗测量,发现它们的内耗峰温与测量起始温度有密切联系。     

Electromechanical properties of Pb(In(1∕2)Nb(1∕2))O(3)-Pb(Mg(1∕3)Nb(2∕3))O(3)-PbTiO(3) single crystals

The Pb(In(1∕2)Nb(1∕2))O(3)-Pb(Mg(1∕3)Nb(2∕3))O(3)-PbTiO(3) (PIN-PMN-PT) crystals were studied as function of phase and orientation. The properties, including the Curie temperature T(C), ferroelectric-ferroelectric phase transition temperature T(R∕O-T), coercive field, and piezoelectric∕dielectric responses, were systematically investigated with respect to the composition of PIN-PMN-PT crystals. The Curie temperature T(C) was found to increase from 160 to 220 °C with ferroelectric-ferroelectric phase transition temperature T(R-T) and T(O-T) being in the range of 120-105 °C and105-50 °C, respectively. The piezoelectric activity of PIN-PMN-PT crystals was analyzed by Rayleigh approach. The ultrahigh piezoelectric response for domain engineered [001] (1600-2200 pC∕N) and [011] (830-1550 pC∕N) crystals was believed to be mainly from the intrinsic contribution, whereas the enhanced level of piezoelectric and dielectric losses at the compositions around morphotropic phase boundaries (MPBs) was attributed to the phase boundaries motion.     

等规度和热处理对聚丙烯硬弹性膜力学性能的影响

选取聚丙烯硬弹性膜专用料树脂S801和F401,引入二甲苯可溶物含量、差示扫描量热法和连续自成核退火(SSA)热分级联用的方法,研究了两者等规度的差异;对在不同温度下热处理(105℃、130℃、140℃和150℃下退火)的硬弹性膜,通过二向红外、回弹率和单轴拉伸测试所获得的结果,从取向和结晶的角度进行分析。发现退火过后,取向度和结晶度都有了显著的提升。同时,随着退火温度升高,一次屈服强度下降,二次屈服强度上升,这与材料内部的取向和结晶有关;具有更高等规度的S801比F401具有更高的模量。在结晶度相同时,高等规度的样品具备更高的回弹率,说明取向度对于聚丙烯硬弹性膜的回弹率的贡献比结晶度更大。     

Investigation of Eu-doped mesoporous titania phosphor with enhanced luminescence

A novel mesoporous TiO2 phosphor doped with Eu was synthesized through a facile hydrothermal synthesis method using cetyltrimethylammonium bromide as structure template reagent. The samples were characterized by X-ray diffraction, N2 adsorption-desorption, scanning electron microscope, high-resolution transmission electron microscopy, ultraviolet visible diffuse reflectance, X-ray photoelectron spectroscopy, and three dimensional Photoluminescence. The X-ray diffraction results demonstrated that the products were anatase type with polycrystalline. N2 adsorption-desorption analysis showed that the samples were of high ordered double mesoporous structures. Eu-doped mesoporous TiO2 indicated the typical fluorescent spectra of Eu3+ ion occurred: the excited-states at 5L6 (394 nm), 5D2 (465 nm) and 5D1 (535 nm); the main emission peaks at 592 and 617 nm, corresponding with the transitions 5D0 --> 7F1 and 5D0 --> 7F2, respectively. Meanwhile, the phenomena of Eu(3+)-doped mesoporous TiO2 phosphor with efficient nonradiative energy transfer from the mesoporous TiO2 host to the activator Eu3+ ions was observed and possible emission mechanism was proposed. High dispersion of Eu in mesoporous TiO2 matrix was responsible for enhanced luminescence.     

Conical and biconical ultra-high-Q optical-fiber nanowire microcoil resonator

New 3D geometries of the optical nanowire microcoil resonator are suggested and investigated theoretically. The dependence of the Q factor on coupling parameters is calculated and compared for three different profiles. Results suggest that ultra-high-Q resonators can be fabricated more easily when the nanowire microcoil resonator has a biconical profile.     

无机杂化纳米晶最新研究进展

无机杂化纳米晶是2种或多种无机材料纳米晶通过界面外延而获得的纳米系统.综述了无机杂化纳米晶研究的国内外最新发展,重点讨论了现有各制备方法的关键控制因素以及组元间的作用机制对产物性能的影响,展望了该领域今后的研究方向.     

分块特征匹配与局部差分结合的运动目标检测

针对摄像机在运动情况下运动目标检测问题的研究,提出了一种尺度不变特征变换图像分块特征匹配和局部差分算法相结合的运动目标检测方法。该方法不仅可以减少图像配准参数求解所需要的时间,弥补全局运动补偿对图像完整性的影响,并且可以在摄像机运动的情况下准确地检测出运动目标。 实验证明了该方案的有效性。     

电动汽车造型设计分析

内燃式发动机汽车的污染问题已经迫在眉睫,而新能源汽车则能很好地解决这一问题.其中电动汽车能大大提高能量利用率,在原本的内燃式发动机汽车的机械传动被更改为电能传动时,不必要的传动损耗被减少.电动汽车的能源利用效率高达19％以上,而内燃式发动机汽车则低于12％.因此电动汽车较于内燃式发动机汽车拥有较多优势,大力发展电动汽车也是大势所趋.本文首先分析了电动汽车的发展背景,在此基础上提出电动汽车的造型趋势,对轻量化设计和模块化设计重点进行了分析.其次基于人机工程学对电动汽车造型的主要人机界面进行了分析.     

氧化石墨烯/酚醛树脂原位复合材料的热性能和动态力学性能

采用改进的Hummers法制备氧化石墨烯(GO),通过超声分散与苯酚、甲醛进行原位聚合,将所得原位聚合树脂与其它填料一起通过辊炼、模压成型制备GO/酚醛树脂(PF)原位复合材料。研究GO含量对GO/PF原位复合材料的热性能、力学性能、动态力学性能、蠕变和应力松弛的影响,使用扫描电子显微镜(SEM)观察复合材料的冲击断面形貌。研究结果表明,当GO加入量为1%时,GO/PF原位复合树脂的初始热分解温度比纯酚醛树脂(PF)提高了55.8℃;当GO加入量为0.25%时,GO/PF原位复合材料的冲击强度提高18.6%;当GO加入量为0.5%时,GO/PF原位复合材料的储能模量比纯PF复合材料提高78.3%,Tg提高了8.9℃。SEM观察发现,GO/PF原位复合材料的冲击断面凹凸不平,表明GO的加入能有效提高PF复合材料的力学性能。