苯乙烯－甲基丙烯酸共聚物和聚环氧丙烷共混体系的相容性研究

 本文用傅里叶交换红外光谱法（ＦＴＩＲ）表征了苯乙烯－甲基丙烯酸共聚物Ｐ（Ｓ－ＭＡＡ）和聚环氧丙烷（ＰＰｒＯ）共混体系的相容性．用谱带分离的技术比较准确地测定了共混体系中几种羰基的吸光系数比，并且用简明的方法定量计算了它们之间平衡的平衡常数．同时实验还表明共混组分中聚醚的分子量、分子结构、Ｐ（Ｓ－ＭＡＡ）中ＭＡＡ的含量以及共混组分的比例和体系的相容性有密切的关系．     

PIV技术在气体界面不稳定性实验研究中的应用

采用粒子图像测速(Particle Image Velocimetry,PIV)技术,以乙二醇烟雾作为示踪粒子,实验测量了平面激波作用下SF6气柱-空气界面Richtmyer-Meshkov不稳定性演化图像和二维速度场.测量结果揭示了不稳定性流场的典型特征和细微结构,与高速摄影和数值模拟结果符合,说明建立的PIV技术适...     

大气颗粒物滞留时间的确定方法及初步实验验证

通过研究大气颗粒物中222Rn子体活度比与颗粒物平均寿命之间的关系,建立了基于活度比估算大气颗粒物滞留时间(residence time of atmospheric aerosol,RTAA)的方法,并在相对理想条件下进行了实验验证.当氡室浓度稳定为1.816kBq/m3时,由214Bi/214Pb活度比计算出的RTAA为112.17min,与氡室的平均换气时间(104.17min)相当,表明大气颗粒物中同一衰变链上的放射性核素活度比(如214Bi/214Pb,210Bi/210Pb或210Po/210Pb)可以用于估算RTAA.     

一种用于同位素分离在线穆斯堡尔谱学的PPAC

研制了一种用于同位素分离在线穆斯堡尔谱学的平行板雪崩计数器，计数器仅重40g。用它测量由穆斯堡尔共振吸收后放出的内转换电子，采用85％^119Sn同位素增丰的SnO2作为阴极吸收材料，测得的穆斯堡尔谱的信噪比为11，是一种适合在线穆斯堡尔实验的计数器。对该计数器的性能进行了讨论。A Parallel Plate Avalanche Counter （PPAC） with weighted about 40 g was developed for isotope separator on-line Moessbauer Spectroscopy. It detects the internal conversion electrons emitted from the resonance Moessbauer nuclide. The signal-to-noise ratio of the spectra reaches 11 for 85% enriched ^119SnO2 cathode and absorber. It is an effective detector for on-line Moessbauer experiments. The perform ance of the counter was discussed in detail.     

基于梯度的动态分块迭代阈值图像二值化方法

在传统的Ostu和Bernsen算法基础上,针对亮度不均的大幅面图像二值化问题,提出了一种基于图像梯度的动态分块迭代求取阈值的二值化方法.实验验证了该方法对于由线阵CCD扫描获得的低对比度、亮度不均的大幅面图像二值化的有效性.     

Size distribution of sulfur species in fine and ultrafine aerosol particles using sulfur K-edge XANES

The sulfur species existing in different size aerosol particles were determined based on the ＇white line＇ energy shift and the features of post edge structure of sulfur K-edge XANES （X-ray Absorption Near Edge Structure）. The results indicated that sulfates were dominant sulfur species in aerosol particles. However, small amount of reductive sulfur species were also found in the ultrafine aerosol particles（〈0.1 μm）. Sulfates in aerosols mostly exhibited as （NH4）2SO4 and gypsum. than 0.952 μm, while gypsum was the dominant sulfate Most （NH4）2SO4 distributed in aerosol particles finer in coarse aerosols.     

Spin-glass state and ferromagnetic order in Cu(II)－Fe(III) cyanides

The static and dynamic magnetic properties of a Prussian blue analogue, molecular magnet Cu^Ⅱ_{3}[Fe^Ⅲ(CN)_6]_2·3NH_3·6H_2O were investigated in detail. The H dependence of the linear AC susceptibility, the irreversibility in the field-cooled (FC)/zero-field-cooled (ZFC) magnetization (M_{FC}/M_{ZFC}) and the relaxation of M_{ZFC} suggest that the magnetic system can be visualized as containing a ferromagnetic cluster of spin below T_C, mixed with small spin-glass clusters formed below temperature T_g less than T_C. The observed magnetic properties are explained with a ferromagnetic-spin-glass phase model. The magnetic ordering of the sample occurs below 19.8K.     

胶体量子点电致发光器件的研究进展

胶体量子点因其性质稳定、可溶液加工、发光颜色易于调节、色彩饱和度高等优点在固体照明、平板显示、红外通讯等领域引起人们高度关注.本文详细介绍了最近胶体量子点电致发光领域取得的重要进展,包括基于 II-VI 族(CdSe、CdTe、PbS、PbSe),III-V 族(InAs、InP),和 I-III-VI 族(CuInS、CuInSe)的量子点电致发光二极管.     

基于邻域统计编码的轮廓提取在CCD二维多尺寸检测中的应用

为了更有效地从二值图像中提取更高质量的曲线轮廓,提出一种基于邻域统计编码的轮廓提取算法,它能在快速地提取出待测零件轮廓的同时,滤除毛刺和噪声.在检测精度不变的情况下,具有速度高和鲁棒性较好的特点.     

苯乙烯－甲基丙烯酸共聚物和聚环氧丙烷共混体系的相容性研究

本文用傅里叶交换红外光谱法（ＦＴＩＲ）表征了苯乙烯－甲基丙烯酸共聚物Ｐ（Ｓ－ＭＡＡ）和聚环氧丙烷（ＰＰｒＯ）共混体系的相容性．用谱带分离的技术比较准确地测定了共混体系中几种羰基的吸光系数比，并且用简明的方法定量计算了它们之间平衡的平衡常数．同时实验还表明共混组分中聚醚的分子量、分子结构、Ｐ（Ｓ－ＭＡＡ）中ＭＡＡ的含量以及共混组分的比例和体系的相容性有密切的关系．