光学瞄具出瞳直径、出瞳距离与放大率现代测试技术研究

针对光学瞄具出瞳直径、出瞳距离与放大率的现代测试要求，在分析原有传统的各种检测原理与方法的基础上，本系统采用了一种基于CCD摄像技术、精密机械技术、光学技术和计算机控制与图像处理技术的现代光学测试原理与方法。测试过程中采用CCD细分技术，提高了图像的分辨率和目标图像的定位精度。出瞳直径与出瞳距离测试精度达到0.01 mm，测试范围为1～100mm，放大率测试精度小于1%，而且大大减轻了疲劳强度。     

粗糙集理论在文本分类算法中的应用

文本分类常采用的算法一般是基于向量比较的分类技术.文本中关键字较多,形成的特征向量维数相当高,因而会导致分类比较处理的运算量太大,而降低维数后又会不可避免地丢失有用信息.将粗糙集理论应用于分类处理过程中可有效地解决此问题.     

一类近三角剖分图的上可嵌入性

一个图在某个曲面上的嵌入三角剖分该曲面,那么这个图是上可嵌入的。对于一个近三角剖分图却不一定是上可嵌入的。已经证明了平面近三角剖分图的上可嵌人性与独立边集之间的关系是：若G的对偶图G^＊有[1/2φ]个独立边集．那么图G的最大亏格γM（G）=[β（G）/2]-1。进一步讨论了平面近三角剖面图G有k个三角△1,△2,…,△A其上可嵌入的条件。     

区间值Fuzzy矩阵

在区间值Fuzzy集的理论上,定义了区间值Fuzzy矩阵与[λ1,λ2]—截矩阵,并讨论了它们的基本性质与运算.     

从横向造型特征统一性看奥迪品牌发展

汽车行业的发展已从传统的技术型驱动转变为品牌文化与技术型双重驱动。一方面．用户希望从产品背后得到更多的东西;另一方面,汽车厂商希望通过“提炼信息然后不断强化”的造型手法增强用户粘性,汽车造型设计中的横向造型特征统一性作为构建汽车品牌文化的载体和手段已发展为汽车企业的核心竞争力。文童将奥迪汽车的横向造型特征统一性分为车身侧面、车身前脸、车身尾部三个部分进行分析,探讨汽车的横向造型特征统一性与汽车品牌发展的关系。     

Further Results on Adaptive State-feedback Stabilization for a Class of Stochastic Nonholonomic Systems with Time Delays

International Journal of Control, Automation and Systems - This paper further studies the adaptive stabilization problem for a class of stochastic nonholonomic systems with time delays, unknown...     

Modeling and analysis of the compatibility of poly(ethylene oxide)/poly(methyl methacrylate) blends with surface and shear inducing effects

The compatibility of poly(ethylene oxide) (PEO) and poly(methyl methacrylate) (PMMA) blends was studied over a wide range of compositions at 400 K by mesoscopic modeling. Sixteen patterned surfaces of four types were designed and designated as “ci,” “co,” “gra,” and “rg” to study their influence on changing the microscopic phase morphology. The topography of the “ci” series surfaces was shaped by semicircular balls. Different radii were applied to simulate different degrees of surface roughness. The “co” series were composed of cubic columns as the mask, and the cubic columns were separated by equal spaces. Various sizes and heights of columns were used to simulate different degrees of surface roughness. The “gra” series were composed of surfaces with different areas of section and the same height to simulate different degrees of surface roughness. The “rg” series were composed of concentric cuboids with continuous increasing heights and sizes. The “co” series surfaces were the most efficient distribution in changing the microscopic phase morphology, the “gra” and “rg” series surfaces were both the secondary, and the “ci” series surfaces placed the last. The results show that the effect of inducing surfaces depended on both the pattern of surfaces and the compositions of the blends. The shear effect was effective in changing the phase morphology, but its influencing effect depended on not only the shear rate, but also the compositions of the blends, especially when the blends were rich in PEO. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

利用污水处理厂活性污泥生产甲醇、合成氨技术的研究

文章提出了利用污水处理厂活性污泥代替褐煤和无烟粉煤混合制造型煤,用于生产甲醇及合成氨的方案,得到了各原料的最佳配比为:腐植酸600 kg,烧碱50 kg,活性污泥加入量1200-1800 kg,粉煤加入量1-20 t。从入炉原料气化和甲醇、合成氨的产品转化看,生成的合成气成份符合工艺要求,产品产量稳定。     

Chemical looping steam methane reforming using Al doped LaMnO3+δ perovskites as oxygen carriers

Chemical looping steam methane reforming (CLSMR) is capable of co-production of high-quality syngas and pure hydrogen, and it is important to develop appropriate oxygen carriers for this process. In this work, LaMn_1-xAl_xO_3+δ (x = 0, 0.1, 0.3, 0.5, 0.7) perovskites were investigated as oxygen carriers for CLSMR by means of characterizations and fixed-bed tests. The characterization and test results suggested that the substitution of Al leaded to more surface active sites and higher symmetry of crystal structure, which facilitates the activation of methane molecule on the surface and the formation of the oxygen vacancy in the bulk of the oxygen carrier particles, increasing the release rate of selective oxygen and the yield of syngas. The yield of CO₂ declined with the Al doped proportion due to the decrease of the mount of Mn⁴⁺ and surface absorbed oxygen. The substitution of Al cations could stabilize the crystal structure and prevent the destruction of perovskite structure. No carbon formed on LaMn_1-xAl_xO_3+δ with x from 0 to 0.5 and a long period of partial oxidation was achieved to produce high-quality syngas with the H₂/CO ratio of 2 and pure hydrogen, while carbon deposition occurred on the LaMn_0.3Al_0.7O_3+δ oxygen carrier. LaMn_0.5Al_0.5O_3+δ possessed the best performance with CO selectivity of 96.4%, the CO yield of 1.70 mmol·g⁻¹, the H₂ yield of 3.32 mmol·g⁻¹ in the reduction stage and the H₂ yield of 1.98 mmol·g⁻¹ in the oxidation stage on average in 20 cyclic redox tests. LaMn_0.5Al_0.5O_3+δ exhibited good thermal stability and cyclic performance. It can be deduced that LaMn_0.5Al_0.5O_3+δ perovskite is a potential oxygen carrier for cyclic CLSMR.     

A simple method of preparing ordered and three-dimensionally-interconnected macroporous carbon with mesoporosity by using silica template

A simple and cost-effective method for the production of porous macro–meso structures is proposed. The approach involves using of monodispersed silica particles and in situ polymerized silica network as a removable template, and using resorcinol-sucrose derivative polymer as a carbon source. The three steps – carbon precursor, silica particles, template – are synthesized simultaneously through sol–gel reaction in one-pot system. The sample prepared by this method was characterized by scanning electron microscopy (SEM) and nitrogen adsorption and desorption, and the results present us a well long-ranged ordered structure and three-dimensionally interconnected macroporous carbon with mesoporosity.