纳米二氧化钒薄膜的电学与光学相变特性

采用双离子束溅射氧化钒薄膜附加热处理的方式制备了纳米二氧化钒薄膜。在热驱动方式下,分别利用四探针测试技术和傅里叶变换红外光谱技术对纳米二氧化钒薄膜的电学与光学半导体-金属相变特性进行了测试与分析。实验结果表明,电学相变特性与光学相变特性之间存在明显的偏差,电学相变温度为63 ℃,高于光学相变温度,60 ℃;电学相变持续的温度宽度较光学相变持续温度宽度宽;在红外光波段,随着波长的增加,纳米二氧化钒薄膜的光学相变温度逐渐增大,由半导体相向金属相转变的初始温度逐渐升高,相变持续的温度宽度变窄。在红外光波段,纳米二氧化钒薄膜的光学相变特性可以通过光波波长进行调控,电学相变特性更适合表征纳米VO₂薄膜的半导体-金属相变特性。     

分子模拟用于尤文肉瘤EWS-FLI1蛋白HLA-A2.1限制性CTL表位的筛选

为获得尤文肉瘤EWS-FLI1融合蛋白有效的HLA-A2.1限制性CTL表位, 综合运用BIMAS, SYFPEITHI, Predep和IEDB方案对EWS-FLI1进行CTL表位的预测, 得出8个CTL表位9肽序列; 应用多项式方案、量化基序方案对8个表位9肽进一步进行筛选, 获得其中4个9肽序列, 并进一步运用分子模拟方法初步模拟了4个表位肽与HLA-A2.1分子间的相互结合作用; 应用标准Fmoc方案合成CTL表位肽, RP-HPLC与MS分别鉴定合成肽的纯度与分子量; 通过亲和力实验验证了表位肽QIQLWQFLL_{(EWS-FLI1 304)}与HLA-A2.1有较强的结合力, 从而为表位肽的后继免疫学特性研究提供了基础. 本研究提供了一个合理高效的表位筛选方法.     

LUND面积定律产生子在R值测量中的应用

对Lund弦碎裂模型强子化面积定律严格求解,得到e⁺e^－湮没产生少体初始强子态的遍举分布.基于面积定律的新产生子LUARLW在2—5GeV能区的模拟结果与BES数据的多种谱分布符合很好,用于BES上强子产生总截面测量的强子探测效率的估计.     

用激光三角法重构混凝土断裂面三维轮廓与断裂能分析

采用基于激光三角法的测试方法对混凝土断面表面轮廓进行了三维重构,初步的断面分析结果表明,相对于传统断面分析方法,本试验方法实现了断面的无损、快速和准确的测量分析,在测量到的断面基础上,给出了本试验所得到的混凝土材料断裂能与分维的关系。     

中立抛物型偏微分方程解的强迫振动

本文讨论一类多滞量中立抛物型偏微分方程解的振动性质 ,获得了其一切解振动的充分条件 ;指出了与普通抛物型偏微分方程质的差异 .     

The Bifurcation of the Equatorial Periodic Orbit of the Planar Polynomial Vector Fields

In this paper, we have obtained the necessary and sufficient condition for the set of points at infinity on the plane R ² to be a periodic orbit which is called an equatorial periodic orbit of a planar vector field X(x), and the formulae about the multiplicity of the equatorial periodic orbit of X(x). We have also proved that the main result of [9] is erroneous with regard to the formulae. This work is supported by the NSF of China     

自相关法测量激光超短脉冲时域分布的解相关

本文论述一种从典型的自相关法测量得到激光超短脉冲时域分布的有效方法,这种方法不必进行另外的光谱测试及假定脉冲形状。     

Kl4 decays

An effective theory of large-N_C QCD of pseudoscalar, vector, and axial-vector mesons has been used to study six K_l4 decay modes. It has been found that the matrix elements of the axial-vector current dominate the K_l4 decays. PCAC is satisfied. A relationship between three form factors of the axial-vector current has been predicted. Partial-wave analysis has been done. Non-zero phase shifts are originated in ρ→ππ. The decay rates are calculated in the chiral limit. In this study there is no adjustable parameter. Received: 17 October 2000 / Accepted: 20 February 2001     

P同位素的质子滴线核研究

研究了在相对论平均场近似下P同位素的滴线核的性质,首先在理论上探讨了25P作为P的滴线核存在的可能性及其可能具有的质子晕结构,然后给出了在兰州放射性束流装置上25P的实验鉴别结果. Great progress was made on the study of P isotope both in theory and in experiments, but the final conclusion about the dripline of P isotope has not been made. In this article the properties of P isotope was studied in the frame work of relativistic mean field (RMF). First the probability of 25P as the dripline nuclei of P isotope and the proton halo structure of 25P was discussed, and then the RIBLL experiental result of 25P is presented.     

卤代-2-(3-甲基-5-取代-4H-1,2,4-三唑-4-基)-苯甲酸的合成

邻氮基苯甲酸;缩合反应;卤代-2-(3-甲基-5-取代-4H-1;2;4-三唑-4-基)-苯甲酸的合成