太赫兹大气传输特性实验研究

太赫兹在高速率通信、高分辨力雷达等方面具有广阔的应用前景,而对太赫兹辐射的大气传输特性及其规律进行系统的理论与实验研究则是发展利用该频谱资源的基础条件。对大气作用于太赫兹频段电磁辐射的吸收衰减进行了实验测试研究。通过双光路的差分系统设计,尽可能地减小太赫兹辐射源输出功率不稳定性所产生的系统误差,完成大气模拟环境下太赫兹波段多个频点传输的功率变化测定,以探索大气环境对不同频段THz波衰减的规律性;同时,建立太赫兹大气传输特性动态数据库对海量大气环境数据进行有效地分析,为实验数据处理及理论研究提供支持。收稿日期:; 修订日期:     

异核碱金属二聚物NaK的激光诱导荧光光谱

用Ar~+激光器488nm输出作为激发光源,获得NaK分子的荧光谱,对它的标志和分析可以了解该分子D~1Ⅱ激发态的能级结构以及在其中所进行的各种能量转移过程。     

连续统与Turing度

令Ｄ为所有Ｔｕｒｉｎｇ度的集合，≤为Ｄ上的图林化归关系．一函数ｆ：Ｄ→Ｄ称为前进函数如果对任何ａ∈Ｄ，ａ≤ｆ（ａ）。对于一个前进函数ｆ，我们说Ｄ中的两个度ａ，ｂ是ｆ－不可比较的，如果ａ≮ｆ（ｂ）且ｂ ≮ｆ（ａ），否则是ｆ－可比较的．本文的一个主要结果是：在ＺＦＣ中连续统假设成立当且仅当存在一个前进函数ｆ：Ｄ→Ｄ使得Ｄ中任何两个度都是ｆ－可比较的.     

Comparison on the antioxidant capacity of selected fruits and vegetables and their separations

Several kinds of fruits, including apple, pear, and grape, and vegetables, including onion and tomato, were studied in this paper. FRAP and DPPH assays were used to determine the antioxidant activity of ethanol extracts and their separations. After being extracted, different phenolic compounds were separated on Sephadex LH-20 column. EC1 and EC50 were used to show the ferric reducing ability and DPPH scavenging activity. The results indicated that the Fe-reducing ability order of different extracts was different with that of DPPH scavenging ability. The mutual effect of the substances in the mixture influenced the antioxidant activity of the separations. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 333–335, July–August, 2006.     

Application of multimode fiber optical sensor in optical tomography technology

In this paper, an attempt to use a multimode optical fiber sensor in tomography is made. Two types of lens, one sphere and one cylinderical, are designed for two terminals of the fiber. It solves the problem of insufficient power collection of natural light beam using current fiber with polished terminals. A theoretical analysis of the relationships among the sphere lens radius, the cylinderical lens radius, the refractive index of the fiber is carried out. The relationship between the scanning angles and the number of the optical fibers is experimentally investigated in the air medium.     

Controllable optical delay line using a Brillouin optical fiber ring laser

A controllable optical delay line using a Brillouin optical fiber ring laser is demonstrated and a large timedelay is obtained by cascading two optical fiber segments. In experiment, a single-mode Brillouin opticalfiber ring laser is used to provide Stokes wave as probe wave. We achieve a maximum tunable time delayof 61 ns using two cascading optical fiber segments, about 1.5 times of the input probe pulse width of 40ns. In the meantime, a considerable pulse broadening is observed, which agrees well with the theoreticalprediction based on linear theory.     

飞机某复合材料弯管的振动主动控制

针对某飞机上典型的复合材料弯管结构的振动 ,采用压电元件作为传感器和作动器 ,通过有限元分析其振动模态以确定压电元件的施加位置 ,进一步利用自适应前馈控制策略 ,对其振动进行了主动控制 ,最终取得了有效的减振效果     

Existence and global exponential stability of periodic solution of CNNs with impulses

Sufficient conditions are obtained for the existence and global exponential stability of a unique periodic solution of cellular neural networks with variable time delays and impulses by using Mawhin’s continuation theorem of coincidence degree and by means of a method based on delay differential inequality.     

集优化问题的广义适定性与解的稳定性

本文研究了集优化问题的适定性与解的稳定性. 首次利用嵌入技术引入了集优化问题的广义适定性概念, 得到了此类适定性的一些判定准则和特征, 并给出其充分条件. 此外, 借助一类广义Gerstewitz 函数, 建立了此类适定性与一类标量优化问题广义适定性之间的等价关系. 最后, 在适当条件下研究了含参集优化问题弱有效解映射的上半连续性和下半连续性.     

去甲斑蝥素对人真皮淋巴管内皮细胞体外三维培养淋巴管生成的影响及其机制

目的探讨去甲斑蝥素（NCTD）对人真皮淋巴管内皮细胞（HDLEC）体外三维培养淋巴管生成的影响及机制。方法建立HDLEC体外培养淋巴管生成模型,随机分为NCTD组（加1/3IC50NCTD40nM）与空白对照组,作用24h,观察两组淋巴管生成的形态变化;并采用免疫细胞化学、Westernblot试验和qPCR技术测定比较两组淋巴管生成因子（VEGF-C、VEGF-D和VEGFR-3）蛋白和基因表达。结果NCTD组的HDLEC细胞形态发生改变,很少形成管状结构,时间延长后细胞出现变圆、离壁、浮起、死亡;且NTCD组淋巴管生成（10.9±2.3）个,明显少于空白对照组（68.4±5.2）个（P＜0.01）。免疫细胞化学染色、Westernblot试验结果显示,NCTD对HDLEC三维培养淋巴管生成中的VEGF-C和VEGF-D的蛋白表达下调（P＜0.01）。qPCR检测显示,NCTD对VEGF-C、VEGF-D和VEGFR-3的基因表达明显降低（P＜0.01）。结论NCTD对通过下调淋巴管生成因子VEGF-C、VEGF-D的蛋白和基因表达,产生抗淋巴管生成的作用。