光学条纹相机时间扫描性能应用

对相机全屏扫速性能进行了系统分析,发现基于相机整体的平均扫速及扫速非线性处理扫描时间的传统方法不能反映相机空间畸变现象,并且扫速非线性放大了数据处理不确定度,从而降低了相机应用价值。建立了一套基于全屏扫速及扫速不确定度的扫描时间精细处理方法,它自洽消除了相机的空间畸变和扫速非线性的系统性影响。开展了理论分析和验证实验,结果表明:精细处理方法很容易使扫描时间数据处理相对不确定度降低到1%以内,显著提高了条纹相机时间扫描精度和应用可靠性。     

A general method for the synthesis of monodisperse hollow inorganic-organic hybrid microspheres with interior functionalized poly(methacrylic acid) shells

Hollow inorganic-organic hybrid microspheres, such as silica, titania, and zirconia, with interior poly(methacrylic acid) (PMAA) functionalized shell were synthesized by a general method containing a two-stage reaction. The hollow inorganic shell-layer with interior polymeric component was formed over the PMAA template during the second-stage controlled hydrolysis of inorganic precursors together with disintegration of PMAA cores and adhering to the interior wall of the silica during the drying process due to the capillary force as well as the competitive hydrogen bond interaction. In this process, PMAA microspheres were prepared by distillation precipitation polymerization of methacrylic acid (MAA) in acetonitrile as the first-stage reaction. The present work elaborately investigated the effects of the reaction conditions, including the amount of the tetraethyl orthosilicate (TEOS) precursors and the amount of ammonium hydroxide catalyst on the morphology and structure of the resultant hollow composite microspheres, which were characterized by transmission electron microscopy (TEM), Fourier-transform infrared spectra (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption.     

Spin-dependent transport induced by magnetization in zigzag graphene nanoribbons coupled to one-dimensional leads

We study spin transport in a zigzag graphene nanoribbon sample with two ferromagnetic strips deposited on the two sides of the ribbon.A tight-binding Hamiltonian was adopted to describe the sample connected to two onedimensional leads.Our theoretical study shows that the resonance peaks of conductance for the spin-up and spin-down electrons are separated for the parallel configuration of the ferromagnetic strips,while they are not separated for the case of antiparallel configuration.This means that giant magnetoresistance can be produced at particular energies by altering the configurations of the ferromagnetic strips,and the device can be designed as a spin filter.     

白酒单体物质紫外荧光光谱研究

白酒荧光光谱是由各种单体物质的荧光共同叠加而表征出来的。不同品牌的白酒中所含的单体物质种类基本相同,都包括水、酒精以及各种微量成分,然而其荧光光谱却差别很大。白酒中的各种单体物质成分究竟是如何对白酒的荧光光谱产生影响,至今未见相关报道。通过对白酒中的主要单体物质,包扩酒精、水及各种主要的微量成分(共10种)在不同激发波长下产生的荧光光谱进行测定,并将其与已测定的大量白酒三维荧光光谱进行对比发现,可以对白酒的荧光光谱产生影响的单体物质是乙醇和主要微量成分。白酒主要微量成分中醇类、酸类、酯类和醛类物质对其荧光光谱都有着一定的影响,但各自影响的程度及影响的光谱范围又各自有所不同。研究结果对白酒荧光光谱的进一步细化研究有着重要的意义。     

胭脂红荧光光谱机理研究

胭脂红是食品添加剂中最常用的一种食用色素之一,国家标准对其在食品中添加的剂量有明确的规定,研究其荧光光谱特性具有一定的实际意义。文章分别从理论与实验上对220～400 nm不同激发波长下胭脂红标准溶液的荧光光谱进行了分析,结果表明,胭脂红可以产生较强的荧光,分别在420,530,635,687 nm波长处产生了4个荧光峰,各荧光峰的最佳激发波长也不尽相同,文章给出了相应的荧光光谱图。经研究认为胭脂红荧光是由—OH中的n电子的n→π*跃迁和奈环中的π电子的π→π*跃迁这两类跃迁而产生的,其中420 nm处的荧光峰是由n→π*跃迁产生的, 而530, 635和687 nm这3个波长处的荧光峰是由π→π*跃迁而产生的, 同时其4个波长处的荧光相对强度随激发波长的变化相对改变不同,文章分别从微观机理上给出了一定的解释。研究胭脂红的荧光光谱及其特性可为其他偶氮类色素的荧光光谱研究提供参考,同时能为食品安全检测提供新的方法与途径。     

应用荧光光谱和径向基函数神经网络定量检测三聚氰胺

实验发现三聚氰胺溶液在紫外光激发下产生较强荧光,测得其荧光峰在310～600 nm之间,荧光峰值波长为420 nm左右,荧光相对强度与三聚氰胺溶液浓度呈现复杂的非线性关系。提出了采用径向基函数神经网络结合荧光光谱对三聚氰胺溶液浓度进行测定的方法。对每个样本选取30个发射波长值所对应的荧光强度作为网络数据,训练、建立了径向基函数神经网络。应用训练好的径向基函数神经网络,对5种三聚氰胺溶液的浓度进行预测,结果相对误差分别为0.93%,0.09%,0.31%,1.55%,4.61%。该方法能快捷、准确地测定三聚氰胺在溶液中的含量,为三聚氰胺检测及食品安全监管提供了一种新方法。     

Mo(Ⅵ)-5-溴水杨基荧光酮-CTMAB显色反应的研究及应用

研究了新的三元配合物体系Ｍｏ（Ⅵ）－溴水杨基荧光酮－ＣＴＭＡＢ显色反应的条件,最大吸收波长λｍａｘ在５２８ｎｍ,试剂λｍａｘ在４６８ｎｍ,对比度为６０ｎｍ,ε５２８＝１．４７＊１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。该体系选择性好,方法简便、快速,用于测定水样中微量钼,结果满意。     

斑头雁不同组织氨基酸的组成和含量分析

采用高效液相色谱法对斑头雁卵、肌肉和羽毛中17种氨基酸进行了含量的测定,并分析其中必需氨基酸的含量,为斑头雁的保护和利用提供依据。结果表明,斑头雁的卵、腿肌、胸肌和羽毛中均含有17种氨基酸,必需氨基酸含量较高,配比合理,有较高的营养价值。     

聚集态和陷阱对交联聚乙烯真空沿面闪络特性的影响

研究了半结晶聚合物交联聚乙烯的聚集态和陷阱等对真空沿面闪络特性的影响.交联聚乙烯(XLPE)在135℃下恒温10min后,分别经过-56℃,-25℃淬火处理,自然降温,或1℃/min,0.5℃/min慢速降温等热处理过程,测量了热处理后试样的电气性能、显微结构、陷阱分布和真空中的沿面闪络特性.实验结果表明,与未热处理试样相比,热处理试样的直流闪络电压最高提高了76%,脉冲闪络电压最高提高了19%.认为热处理改变了XLPE试样的聚集态和陷阱,从而提高了XLPE试样的真空沿面闪络性能,提出了可以通过控制半结晶聚合物的聚集态和缺陷结构提高其真空沿面闪络性能.     

Thermal conductivity of micro/nano-porous polymers: Prediction models and applications

Micro/nano-porous polymeric material is considered a unique industrial material due to its extremely low thermal conductivity, low density, and high surface area. Therefore, it is necessary to establish an accurate thermal conductivity prediction model suiting their applicable conditions and provide a theoretical basis for expanding their applications. In this work, the development of the calculation model of equivalent thermal conductivity of micro/nano-porous polymeric materials in recent years is summarized. Firstly, it reviews the process of establishing the overall equivalent thermal conductivity calculation model for micro/nanoporous polymers. Then, the predicted calculation models of thermal conductivity are introduced separately according to the conductive and radiative thermal conductivity models. In addition, the thermal conduction part is divided into the gaseous thermal conductivity model, solid thermal conductivity model and gas–solid coupling model. Finally, it is concluded that, compared with other porous materials, there are few studies on heat transfer of micro/ nanoporous polymers, especially on the particular heat transfer mechanisms such as scale effects at the micro/nanoscale. In particular, the following aspects of porous polymers still need to be further studied: micro scaled thermal radiation, heat transfer characteristics of particular morphologies at the nanoscales, heat transfer mechanism and impact factors of micro/nanoporous polymers. Such studies would provide a more accurate prediction of thermal conductivity and a broader application in energy conversion and storage systems.