Xieite, a new mineral of high-pressure FeCr2O4 polymorph

Xieite, a new mineral, occurs in the shock vein of the Suizhou meteorite. The mineral has an orthorhombic structure and its space group is Bbmm. The cell parameters are a = 9.462（6） A, b = 9.562（9） A, c = 2.916（1）A. The crystal-chemical formula is （Fe0.87Mg0.13Mn0.01）1.01（Cr1.62AI0.25Ti0.08V0.02）1.97O4, or simply formula FeCr2O4. Stronger X-ray diffraction lines are [d （A）, I/Io]： （2.675, 100）, （2.389, 20）, （2.089, 10）, （1.953, 90）, （1.566, 60）, （1.439, 15）, （1.425, 15）, （1.337, 40）. Xieite is a high pressure polymorph of FeCr2O4 and formed by solid-state transformation of chromite under shock-induced high pressure and temperature, in association with other high-pressure minerals including ringwoodite, majorite, lingunite and tuite. The P-Tcondition for the formation of xieite is estimated to be 18--23 GPa and 1800--1950℃, respectively. Xieite has recently been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association （IMA 2007-056）. The mineral name, xieite, is named after Xiande Xie.     

血浆pH 值变化对APTT测定结果的影响

通过在一组血浆中分别加入不同pH 值的HEPES缓冲液,制备出一组pH 值呈梯度变化的血浆样本,以三种APTT试剂进行检测,三种APTT试剂分别以高岭土、硅胶和鞣花酸为激活剂.结果发现血浆pH在7.02～8.16变化范围内,对APTT的测定结果均有影响,其中对以鞣花酸为激活剂的APTT试剂测定结果的影响最大.     

矮秆种质的赤霉酸反应和株高遗传模型的分析

通过赤霉酸处理及遗传模型分析小麦／冰草衍生系的矮秆种质得知：8个矮秆种质均为赤霉酸不敏感型。其中的3648—3652的株高是多基因控制的数量性状,其遗传模型是两对主基因加多对微效基因控制的混合遗传模型。     

“依然”与“仍然”的比较分析

本文在大规模语料的基础上,比较分析现代汉语副词"依然"与"仍然"在句法特征、句式语义和固定格式上的差异。通过分析认为:在句法上,两者都能做状语,而"依然"还可以做谓语;做状语时在大多数情况下两者可以替换。在语义和格式上,"依然"侧重于对静态持续态的修饰,有成词的固定格式;"仍然"可以表动作的间隔重复,并具有更重的转折意味。     

Recent progress in studies on the nano-sized particle layer in rock shear planes

Since the 1990s, an ultramicro-particle texture in nano- or micron-sized scale has been continually found in shear planes of various rocks, and recently further progress was obtained by studying the generic mechanisms on both physics and mechanics. In this article, the characteristics of the nano-sized particle layer in rock shear planes (including the widespread distribution, layering texture, non-linear genetic mechanism, and multiple functions) on an ultra micro-scale were briefly introduced and more information was proposed by analyzing examples from home and broad.We found that there is a paragenetic relationship between the development of shear frictional-viscous and the formation of nano-sized particles and that in the shear movement, partitioning, segregating, and layering in rocks are initiated by the sliding motion of the nano-sized particle layer. Moreover, the plastic rheology of rocks is essentially the movement of ultra micro-sized particle (nano-size and micro-size), and the nano-sized particle layer in rock shear planes are characterized by some particular physical and chemical effects.     

腺病毒载体介导GFP基因在鸭胚和雏鸭体内的表达

本试验旨在探讨腺病毒在鸭胚和雏鸭体内的感染情况,为腺病毒作为外源基因载体在活体上进行RNA干涉奠定基础．将GFP基因重组腺病毒（Adv-GFP）静脉注射15日龄鸭胚和10日龄雏鸭,在感染后不N时间采集组织器官,制作冰冻切片,荧光显微镜观察GFP基因在鸭胚和雏鸭组织器官中的表达,结果发现,GFP基因在Adv-GFP感染后24-72h能在鸭胚肝脏及心肌细胞中表达,在感染后1-5d,GFP基因可在雏鸭肝脏、脾脏、腔上囊中稳定表达,本试验首次证明腺病毒作为安全的外源载体,可介导外源基因在鸭胚和雏鸭体内的靶器官中持续稳定表达,为在鸭上进行病毒病的基因治疗提供了基础数据．     

微型旋风器分离超细粉尘的性能

针对分级领域中存在的问题,研究微型旋风分级器的分级性能,目的是利用微型旋风分级器将1μm左右的超细粉体从细粉中分离出来.首先建立旋风分级器的分离二维数学模型,模型方程解析证实粉尘分级效率只与Stk数有关,对3种微型旋风器在不同进口风速下进行实验研究.实验结果表明:分级效率与Stk数之间的关系在Rosin-Rammler坐标上为一条直线,用新理论计算的分级效率值较其他理论能更好地接近实验值,是一个相对比较准确的分离效率计算方法.对3组微型旋风器在入口风速为15~25 m/s范围内分级时,分级粒径可以达到0.6μm.     

快速公交系统在贵阳的适应性分析

结合贵阳市目前公交系统的运营现状及其公共交通存在的主要问题,分析了贵阳快速公交发展的环境特征以及快速公交系统给贵阳带来的社会效益,经济效益,环境效益。     

TMS320DM642对视频图像欠采样压缩处理的实现

通常采用降采样完成实时视频格式调整。在降采样过程中不可避免地会引入欠采样噪声。为此提出了TMS320DM642上欠采样噪声的处理算法,实现了在TMS320DM642上实时欠采样噪声处理,描述了该程序的优化。其可以支持从CIF（Common Intermediate Format）到SQCIF（Sub-Quarter Common Intermediate Format）的实时视频格式调整。实验结果表明,在网络传输带宽波动时,该方法可有效减小混叠,图像质量清晰流畅。     

A New Method of Color Edge Detection Based on Local Structure Analysis

Human＇s real life is within a colorful world. Compared to the gray images, color images contain more information and have better visual effects. In today＇s digital image processing, image segmentation is an important section for computers to ＂understand＂ images and edge detection is always one of the most important methods in the field of image segmentation. Edges in color images are considered as local discontinuities both in color and spatial domains. Despite the intensive study based on integration of single-channel edge detection results, and on vector space analysis, edge detection in color images remains as a challenging issue.