Track reconstruction using the TSF method for the BESⅢ main drift chamber

We describe the algorithm to reconstruct the charged tracks for BESⅢ main drift chamber at BEPCⅡ, including the track finding and fitting. With a new method of the Track Segment Finder (TSF), the results of present study indicate that the algorithm can reconstruct the charged tracks over a wide range of momentum with high efficiency, while improving the robustness against the background noise in the drift chamber. The overall performances, including spatial resolution, momentum resolution and secondary vertices reconstruction efficiency, etc. satisfy the requirements of BESⅢ experiment.     

扫描型红外成像系统仿真及TOD曲线预测方法研究

针对实际三角形方向鉴别（TOD）阈值温差测试的数据量大、时间长,以及测试结果常具有不稳定和不确定性等问题,提出一种扫描型红外成像系统效应仿真。建立了红外成像系统性能预测仿真平台,并对靶标效应图进行人眼判定。根据人眼判定结果对神经网络进行了训练。由基于BP神经网络的TOD阈值温差预测方法判定仿真样条的方向,统计正确的判定概率,实现TOD曲线的预测。实验结果表明：该方法预测的TOD曲线与实际测量的TOD曲线具有很好的一致性。     

Fabrication of Polyaniline/Silver Nanocomposite Under Gamma-ray Irradiation

Polyaniline (PANI)/silver composite was one-step synthesized under γ-ray irradiation. The structure of the composite was characterized by Fourier transform infrared spectroscopy, UV-Visible, and X-ray diffraction, which indicated that PANI and face-centered-cubic silver were synthesized under γ-ray irradiation. The reaction mechanism were discussed, which revealed that the PANI was formed by the reaction of aniline cation radicals formed by the reaction of aniline cation and ·OH, and Ag was formed by the reaction of Ag⁺ and e^-_aq. The morphology of the composite consisted of PANI nanofibers and Ag nanoparticles, and the mechanism of the morphology formation was discussed, which revealed that the rapid mixing like polymerization process might play an important role. It was revealed that the transport behavior of the composite well fitted with the variable-range-hopping model in 80-300 K and deviated from the model below 80 K.     

壳聚糖与壳寡糖结构及其对放射性核素铀吸附性能

采用酸碱滴定法测定壳聚糖和壳寡糖脱乙酰度分别为90.9%和90.1%,用IR方法表征了壳糖中乙酰基和氨基。 MALDI-FT-MS进一步给出了经葡聚糖凝胶柱纯化后壳寡糖脱乙酰度和聚合度的信息。 通过壳聚糖吸附性能的研究发现,壳聚糖对放射性核素铀具有较强的吸附能力,吸附率达96%以上,即使在大量Cu2+存在情况下,也可高效吸附放射性核素铀,说明壳聚糖有望成为一种新型的放射性核素吸附去污材料。     

弯梁斜跨拱桥合理恒载状态研究

弯梁桥和拱桥相互协作形成的弯梁斜跨拱桥,充分结合了弯梁桥的行车舒适性与拱桥易于布索的特点,大幅度提高了弯梁的跨越能力。本文首先综合斜拉桥索力调整和拱桥合理拱轴线设计方面的经验,研究弯梁斜跨拱桥合理恒载状态的实用设计方法;然后提出了约束松弛的二次规划算法和基于刚度矩阵减少重分析的策略,提高计算的收敛性和求解速度;最后经实桥分析指出设计中应注意的问题,为弯梁斜跨拱桥的应用提供依据。     

ITER纵场磁体支撑屈曲分析与半原型测试件初步设计

针对新设计的ITER纵场重力支撑结构特点,用ANSYS有限元软件对它建立了有限元模型。采用Block Lanczos方法求出了ITER重力支撑的屈曲特征值。分析结果表明ITER重力支撑不会发生屈曲。为了确保新设计结构的可靠性,初步设计了全尺寸支撑的半原型件拟用来对支撑进行工程受力测试。     

不同的衬底温度下GdBa_2Cu_3O_7超导薄膜在(100)SrTiO_3单晶衬底上的生长

影响 Y 系高温超导薄膜制备工艺的因素很多,其中衬底温度被认为是最关键的因素之一.本文工作利用直流磁控溅射快速原位处理的方法,在600—850℃ 的衬底温度范围内,在(100)SrTiO_3单晶衬底上制备了一系列的 GdBa_2Cu_3O_7超导薄膜样品,并对这些样品的超导电性和结构进行了分析.发现,在衬底温度低至670℃ 时,也能得到零电阻转变温度 T_(c0)>88K 的样品.     

多元正态模型的局部影响评价

本文就多元分析中，对具有多元正态分布的多元数据，给出了它们在观测加权（ｃａｓｅ－Ｗｅｉｇｈｔｓ）扰动下模型的局部影响评价，通过实例分析，证实了所得结论的有效性。     

合成CFC-12替代物HFC-134a的CrF_3/AlF_3催化剂的研究 Ⅵ.合成氟代烃的多功能催化剂

合成ＣＦＣ１２替代物ＨＦＣ１３４ａ的ＣｒＦ３／ＡｌＦ３催化剂的研究Ⅵ．合成氟代烃的多功能催化剂吕剑石磊王振宇李惠黎（西安近代化学研究所，西安７１００６５）彭少逸（中国科学院山西煤炭化学研究所，太原０３０００１）关键词氟化铬，氟化铝，氟化物催化剂...