含间隙超音速二元弹翼非线性颤振与主动控制

研究含间隙超音速二元弹翼非线性颤振特性和主动控制问题．采用三阶活塞理论建立了含间隙二元弹翼非线性气动弹性动力学方程,利用Hopf分岔理论、谐波平衡法和数值方法,分析了系统的非线性颤振特性．应用基于微分几何法和二次型最优控制相结合的方法设计非线性系统控制器,推迟临界分岔速度．应用滑模变结构控制方法设计控制器,有效抑制非线性颤振,并讨论了控制参数对控制效果的影响．仿真结果表明,所设计的控制律可以有效地实现对含间隙超音速二元弹翼系统非线性颤振的控制．最后计算了在基础激励扰动下系统的动态响应,分别得到了周期运动、多周期运动、概周期运动以及混沌运动．     

等值理论在医学翻译中的应用

等值理论是西方现代翻译的核心理论,在西方现代翻译理论中占有重要的地位,并且在各种翻译中被应用广泛,但在医学翻译中等值理论却很少被提厦。本文试从等值理论出发,结合医学翻译的特点,从词汇,句子,段落三个方面,就医学翻译中等值理论的应用问题进行探讨。     

Google Earth-based dynamic visualization system for storm surge flood routing

To describe the dynamic process of flood routing intuitively and realistically when storm surge disaster occurs, a method for ArcGIS data and Google Earth （GE） data integration is proposed, which realizes the impor- ting and integrating of basic geographic information into GE. Based on SketchUp and AutoCAD software, three- dimension （3D） visualization of seawall and other tidal defense structures is achieved. By employing Microsoft Foundation Class Library （MFC）, the related system modules and storm surge flood routing dynamic visualization system are developed. Therefore, dynamic visualization of flood routing process and interactive query of sub- merged area and inundated depth are implemented. A practical application case study of Tianjin Binhai New Area provides decision-making support for coastal seawall planning and storm surge disaster prevention and reduction.     

1,5-二芳基-1,4-戊二烯-3-酮类化合物的新合成方法

以乙酰丙酮、芳醛为原料,乙醇为溶剂,氢氧化钠为催化剂的条件下合成了一系列1,5-二芳基-1,4-戊二烯-3-酮类化合物,用核磁、红外等测试手段对化合物进行了表征.结果表明:在10%的氢氧化钠溶液的催化下,产物的产率均在90%以上,与传统的方法相比,该方法具有反应条件温和、操作简单及产率高等优点.     

枳菊解郁汤对抑郁模型小鼠空间学习记忆的影响及其机制

目的:探讨枳菊解郁汤对抑郁模型小鼠空间学习记忆的影响及其机制。方法:以慢性轻度不可预见性应激方法建立小鼠抑郁模型,用高、中和低剂量枳菊解郁汤处理小鼠。通过Morris水迷宫检测各组小鼠学习记忆能力。通过免疫组化检测小鼠海马区和前脑皮层胶质细胞源性神经营养因子(GDNF)的表达。结果:与对照组相比,模型组小鼠的空间学习记忆能力显著降低(P<0.01),海马CA1、CA3和DG区以及前脑皮层GDNF表达明显下降(P<0.05)。与模型组相比,枳菊解郁汤组中高剂量组小鼠能明显改善小鼠的空间学习记忆能力(P<0.05,P<0.01),海马、前脑皮层中GDNF的表达明显增加(P<0.05)。结论:枳菊解郁汤具有抗抑郁作用,其作用机制可能与上调海马和前脑皮层GDNF的表达有关。     

Optical turbulence profiling with single star SCIDAR technique

In order to characterize optical turbulence, we have developed a single star SCIDAR （SSS） for measurement of the distribution of Cn^2 with height. The SSS consists of a 40 cm telescope and a CCD camera for fast sampling of stellar scintillation pattern. Spatio- temporal auto and cross-correlation functions of the single star images are computed, providing vertical profiles of optical turbulence intensity C2（h） and wind speed V（h）. Using this new SSS experiment, profiles of turbulence can be obtained from the ground to the top of atmosphere, allowing the determination of seeing, isoplanatic angle and coherence time. Detailed characteristics of atmospheric optical turbulence are important for active and passive imaging, astronomical site testing, adaptive optics, laser communications, target tracking and designation, and laser beam control. We plan to improve the robotization of the SSS to be able to use it routinely even under harsh weather and altitude conditions that we expect to encounter on the high Tibetan plateau or at Dome A in Antarctica. SSS will also be applied for the site testing campaign of the future Chinese extremely large telescope.     

Late Paleozoic magmatism in South China:Oceanic subduction or intracontinental orogeny?

A gneissic granite with an U-Pb age of 313±4 Ma was found in northeastern Fujian Province,South China.It is an S-type granite characterized by high K2O,Al2O3 and low SiO2,Na2O contents with high A/CNK ratio of 1.22 for the whole rock.Zircons with stubby morphology from the gneissic granite yield 206 Pb/238 U ages ranging from 326 to 301 Ma with a weighted average age of 313±4 Ma,and negative εHf(t) values from -8.35 to -1.74 with Hf model ages (TCDM) of 1.43 to 1.84 Ga.This S-type granite probably originated from late Paleoproterozoic crust in intracontinental orogeny.Integrated with previous results on paleogeographic reconstruction of South China,the nature of Paleozoic basins,Early Permian volcanism and U-Pb-Hf isotope of detrital zircons from the late Paleozoic to early Mesozoic sedimentary rocks,we suggest the occurrence of a late Paleozoic orogeny in the eastern Cathaysia Block,South China.This orogenic cycle includes Late Carboniferous (340-310 Ma) orogeny (compression) episode and Early Permian (287-270 Ma) post-orogenic or intraplate extension episode.Therefore,the late Paleozoic magmatism in the southeastern South China probably occurred during the intraplate orogeny rather than the arc-related process.     

乙二醇的合成工艺的研究分析

主要介绍了目前国内外乙二醇的合成工艺路线,并对部分路线的优缺点做了表述。     

一种融合 UKF 和EKF 的粒子滤波状态估计算法

在扩展卡尔曼滤波算法(Extended Kalman Filter,EKF)和不敏卡尔曼滤波算法(Unscented Kalman Filter,UKF)的基础上,提出一种基于融合的粒子滤波算法(Fusion based particle filter, FPF)。该算法首先利用EKF 与UKF 分别预测粒子状态,然后通过融合算法得到粒子的重要性建议分布,实现粒子状态更新。因为充分利用了量测信息,因而能有效提高状态估计精度。仿真中通过实例将该算法与已有的粒子滤波算法(Particle filter algorithm,PF)进行比较,结果表明该算法各方面性能都有较大改进。     

碱土金属氧化物掺杂CeO2催化1,4-丁二醇选择性脱水合成3-丁烯-1-醇

采用浸渍法制备了碱土金属氧化物MO(MgO、CaO、SrO和BaO)掺杂的MO-CeO2催化剂,通过X-射线粉末衍射、H2程序升温还原和CO2程序升温脱附等手段表征了催化剂的结构和表面性质,并考察其对1,4-丁二醇选择性脱水合成3-丁烯-1-醇反应的催化性能.结果表明,碱土金属氧化物掺杂未改变CeO2的萤石型结构,但可增加MO-CeO2催化剂的氧缺陷位和表面碱性位点,进而提高其催化1,4-丁二醇选择性脱水的活性和3-丁烯-1-醇的选择性.其中,CaO-CeO2催化剂表现出最优的催化性能,3-丁烯-1-醇收率达52.44%.