液相化学法制备超细MoO_3研究

以仲钼酸铵和硝酸为原料,采用液相化学法制备超细MoO3.研究了表面活性剂类型及浓度对产物形貌的影响.结果表明,阴离子型表面活性剂的分散性能优于阳离子和非离子表面活性剂.在添加浓度为1.8mmol/L十二烷基苯磺酸钠(DBS)时,能够制备出分散性较好、粒径为100nm左右的球形超细MoO3粉末.     

气液法制备文石型碳酸钙晶须及影响条件研究

研究了在MgCl2-Ca（OH）2--CO2体系中,气液法制备碳酸钙晶须的形貌和影响条件．结果显示,在此条件下制备的是具有较好形貌和高长径比,且分布均一的文石型碳酸钙晶须,并利用扫描电镜（SEM）、X-射线粉末衍射（PXRD）和傅里叶转换红外（FT—IR）光谱图等手段对其进行了表征．其最佳制备工艺为：反应温度为80℃,CO2的流量为5mL／min,搅拌速度为250r／min,MgCl2溶液浓度为0．4mol／L．     

Establishment of reference mandibular plane for anterior alveolar morphology evaluation using cone beam computed tomography

To propose a method of establishing the reference mandibular plane (MP), which could be reestablished according to the coordinates of the reference points, and then facilitate the assessment of anterior alveolar morphology using cone beam computed tomography (CBCT), sixty patients with bimaxillary protrusion were randomly selected and CBCT scans were taken. The CBCT scans were transferred to Materialism’s interactive medical image control system 10.01 (MIMICS 10.01), and three dimensional models of the entire jaws were constructed. Reference points determining the reference MP were positioned in the coronal, axial, sagittal windows, and the points were exactly located by recording their coordinates in the interfaces of software. The reference MP provided high intra-observer reliability (Pearson’s r 0.992 to 0.999), and inter-observer reliability (intra-class correlation coefficients (ICCs) 0.996 to 0.999).     

An image registration method based on multi-resolution morphology contour detection

Combined with the printing application, an image registration method based on the multi-resolution morphology contour detection was proposed. First, a direction based multi-resolution gray morphology in the scheme was proposed to realize the contour extraction. Then, based on the contour features, the subspace image registration was proposed to deal with issues of the computing complexity appeared in the traditional image registration methods. The proposed image registration was efficiently applied in the defect inspection of printing images.     

一种新型的基于数学形态学和颜色特征车牌定位算法

在分析了车牌定位现有算法优缺点的基础上,本文提出一种新型的综合利用车牌纹理特征、颜色特征和几何特征的快速定位算法.该算法利用数学形态学充分挖掘车牌纹理特征以及消除噪声干扰.把图像分割为若干子区域,利用纹理条件和颜色条件判断,对各子区域进行独特的分类和聚类融合,最终由粗至细精确地定位出车牌所在位置,为后续车牌字符的分割识别步骤打下良好基础.实验结果表明,对于各种情况下的车牌图像,该算法都能有效地对车牌进行定位,具有定位准确率高,运行速度快,抗干扰性强的特点.     

草酸共沉淀法制备(Y,Eu)_2O_3前驱体的研究

以草酸共沉淀法制备(Y,Eu)2O3为前驱体,对比六种沉淀条件对前驱体形貌的影响,其中在沉淀过程中添加氨水并用双加料的方式可制备出形貌上优于商用前驱体,其粒度呈正态分布;通过调节草酸过量的量、沉淀过程中添加氨水的量、合成温度及草酸浓度等沉淀条件可控制前驱体D50在2.5～8.0范围内变化。     

武汉南湖湖区土地利用结构信息熵与湖泊形态变化分形分析

利用1996年～2006年武汉市1∶1万土地利用数据库,结合1991年、1995年、2000年和2002年卫星遥感影像资料,借助系统论中的信息论思想,计算1996年～2006年10年间武汉南湖地区的土地利用结构信息熵和均衡度,并利用边界维数对南湖各时期的岸线形态变化进行定量判断。在此基础上,分析了武汉南湖土地利用结构信息熵和湖泊岸线分维变化之间的相互关系,并对土地利用结构信息熵和湖泊岸线分维在湖泊保护、管理规划方面的应用潜力做了初步探讨。结果表明,从1996年至2006年,南湖湖区土地利用结构的信息熵、均衡度以及岸线分维均出现逐渐减少的趋势,湖区土地利用类型向建设用地不断转变与湖泊人工填占是上述变化的主要原因,武汉城市化过程中人类活动大大加快了城市湖泊发展演化进程。土地利用结构熵、均衡度以及湖泊岸线分维从不同侧面反映了湖泊发展演化过程,能够为城市湖泊生态环境保护、管理规划提供有价值的参考信息,为进一步利用复杂性理论开展城市湖区经济、人口、资源协调发展等研究奠定了必要的基础。     

基于潜在语义分析的自动词法学习技术

潜在语义索引方法是一种无监督的学习方法,能够自动地从未经加工的文本中学习词法分析处理的数据。通过计算单词之间的语义相关性,提高学习的效果。本文首先对词法分析和词法学习的概念和早期出现过的词法学习的方法进行简单阐述,然后描述了基于这一理论进行词法学习的方法,接着是对这一方法的一些改进和测评,最后是结论和展望。     

青球箩纹蛾的形态特征及在苏州地区的发生特点

青球箩纹蛾在苏州地区一年发生2代．通过野外调查和室内饲养,观察其形态,发现其食性较窄,幼虫共5龄,主要危害金叶女贞叶片,老熟幼虫通过在地面土块下做土室化蛹越冬,土壤水分影响蛹体的成活．     

Degradation of collagen in parchment under the influence of heat-induced oxidation: Preliminary study of changes at macroscopic,microscopic, and molecular levels

This paper examines the impact of heat-induced oxidation for new and historical parchment with the purpose of improving diagnostic tools for use in practical parchment conservation. Oxidation was generated by heat aging at 120°C in a dry oven for 24, 48, and 96 hours, respectively. The degradation was assessed on all samples at macrolevel by measuring color changes, at microlevel by measuring the shrinkage temperature as well as by performing a visual assessment of the fibers’ morphology and determining the amount of damaged fibers, and finally, at molecular level where amino acid analysis was used to reveal changes in the oxidized collagen. The study shows that the heat-induced oxidation leads to significant color changes, decrease in hydrothermal stability, as well as changes in the amino acid composition. Surprisingly, the results show that the historical parchment is more sensitive towards dry heat oxidation on a molecular level than is the new parchment. Furthermore, for the first time, we can show that physical damage reflected in the morphological characteristics of fibers can be attributed to oxidation by dry heat.