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Petroleum Science 2014年第2期11卷 318-322页

作者： Liu Xiaocheng Wei Yaodong song jianfei State Key Laboratory of Heavy Oil Processing China University of Petroleum

A handy gamma-ray transmission method for estimating the particle concentration distribution in a fluid catalytic cracking （FCC） riser is proposed. The method is based on an empirical correlation ε（r）= ε-（0.191＋φ25＋3φ11）, which has only one unknown parameter y, hence only one single-beam experimental result is enough to estimate the particle concentration distribution in the riser. In order to verify the feasibility of this method, the particle concentrations of three cross-sections of the laboratory riser were measured and the distribution profiles were compared with those reported in the literature. Furthermore, by comparing other gamma-ray function methods applied in the measurement of risers, this method has distinct advantages, such as the device is simple and has no moving parts, the measurement is rapid, and the safety is high because only one gamma-ray beam is used. Therefore, the method has promising applications in estimating particle concentrations or monitoring operation conditions of risers.

关键词： Gamma-ray riser FCC catalyst concentration measurement

Investigation of Different Coke Samples Adhering to Cyclone Walls of a Commercial RFCC Reactor

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China Petroleum Processing & Petrochemical Technology 2016年第1期18卷 8-14页

作者： Li Xiaoman song jianfei Sun Guogang Yan Chaoyu Wei Yaodong State Key Laboratory of Heavy Oil Processing China University of Petroleum

The microstructure and properties of the coke samples collected from 4 different wall regions of the cyclone in the reactor of a residue fluid catalytic cracking unit(RFCCU) were analyzed by using the scanning-electron microscope(SEM), and the possible coke formation processes were investigated as well. The results showed that some of the heavy nonvolatile oil droplets entrained in the flowing oil and gas mixture could possibly deposit or collide on the walls by gravity settling or turbulence diffusion, and then were gradually carbonized into solid coke by condensing and polymerization along with dehydrogenation. Meanwhile some of fine catalyst particles also built up and integrated into the solid coke. The coke can be classified into two types, namely, the hard coke and the soft coke, according to its property, composition and microstructure. The soft coke is formed in the oil and gas mixture's stagnant region where the oil droplets and catalyst particles are freely settled on the wall. The soft coke appears to be loose and contains lots of large catalyst particles. However, the hard coke is formed in the oil and gas mixture's flowing region where the oil droplets and catalyst particles diffuse towards the wall. This kind of coke is nonporous and very hard, which contains a few fine catalyst particles. Therefore, it is clear that the oil and gas mixture not only carries the oil droplets and catalyst particles, but also has the effects on their deposition on the wall, which can influence the composition and characteristics of deposited coke.

关键词： FCC reactor cyclone coke formation microstructure characteristics

蜗壳式旋风分离器内气相流场非轴对称特性分析

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化工学报 2007年第5期58卷 1091-1096页

作者：宋健斐魏耀东时铭显中国石油大学(北京)重质油国家重点实验室北京102249

采用Fluent软件对蜗壳式旋风分离器内气相流场进行了数值模拟,并在此基础上对流场的非轴对称特性进行了机理分析。蜗壳式旋风分离器入口结构的非轴对称以及气相旋流的不稳定性造成了气流的旋转中心与旋风分离器的几何中心不重合,从而导... 详细信息

采用Fluent软件对蜗壳式旋风分离器内气相流场进行了数值模拟,并在此基础上对流场的非轴对称特性进行了机理分析。蜗壳式旋风分离器入口结构的非轴对称以及气相旋流的不稳定性造成了气流的旋转中心与旋风分离器的几何中心不重合,从而导致了气相流场三维速度的非轴对称分布以及速度分量由于基准不同而产生的大小和方向变化。环形空间流场的非轴对称性主要是非轴对称入口结构影响的结果,分离空间流场的非轴对称性主要是旋流的不稳定性造成的。根据Rayleigh准则,旋风分离器内旋流流场的不稳定性是固有的,提高流场的旋流数可使流场的不稳定性降低,流场的非轴对称性降低。入口速度的变化不影响旋流数,也不影响流场的非轴对称性,但增加入口截面积比或减小量纲1升气管内径均可提高流场的旋流数,使流场的非轴对称性降低。旋风分离器的非轴对称性可以用角动量参量来描述。

关键词：蜗壳式旋风分离器流场非轴对称角动量

蜗壳式旋风分离器气相流场的非轴对称特性的模拟

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化工学报 2005年第8期56卷 1397-1402页

作者：宋健斐魏耀东时铭显中国石油大学(北京)化工学院北京102249

采用Fluent软件提供的雷诺应力模型(RSM)对蜗壳式旋风分离器内气相流场进行了数值模拟,重点考察流场的非轴对称特性.模拟结果表明旋风分离器环形空间的流场呈现明显的非轴对称分布;筒体空间和锥体空间的流场也存在一定的非轴对称性.旋... 详细信息

采用Fluent软件提供的雷诺应力模型(RSM)对蜗壳式旋风分离器内气相流场进行了数值模拟,重点考察流场的非轴对称特性.模拟结果表明旋风分离器环形空间的流场呈现明显的非轴对称分布;筒体空间和锥体空间的流场也存在一定的非轴对称性.旋风分离器流场的非轴对称性是由于其入口结构不对称产生的,其主要特点是沿轴向气流的旋转中心与旋风分离器的几何中心不重合,旋转中心偏离几何中心的距离和方位在不同的轴向位置而不同,最大约为0.07R.由于气流旋转中心偏离旋风分离器的几何中心,使参考几何中心的径向速度分布呈现明显的非轴对称性,一部分向内,一部分向外.

关键词： Fluent RSM 旋风分离器流场非轴对称

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当代德国大学学费制的历史与现状

全球教育展望 2007年第12期36卷 48-53页

作者：宋健飞高翔翔同济大学德语系

德国大学的免收学费政策曾使无数学子身受其惠,对德国高等教育的普及功不可没。然而,近年来在国内经济形势的压力下和国际教育讲求效率的激烈竞争中,这一政策又一次面临变革的挑战。经反复磋商与辩论,德国教育主管部门已决定重新推出征... 详细信息

德国大学的免收学费政策曾使无数学子身受其惠,对德国高等教育的普及功不可没。然而,近年来在国内经济形势的压力下和国际教育讲求效率的激烈竞争中,这一政策又一次面临变革的挑战。经反复磋商与辩论,德国教育主管部门已决定重新推出征收学费的举措。尽管此做法会对求学者产生不利影响,但从长远的观点来看,却是德国高等教育目前必须迈出的一步。因此,无论是过去的免费还是如今的收费,均属德国大学势在必行的举措。

关键词：德国大学学费免费与收费之争论各州反应新政策之影响

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基于四元数的改进型最小核值相似区边缘检测

计算机应用 2015年第3期35卷 826-829,848页

作者：宋健飞高莉江苏师范大学电气工程及自动化学院江苏徐州221116

针对基于亮度和色度的彩色图像边缘检测在检测过程中忽略亮度和色度之间关联性而导致部分边缘不能有效地被检测出来的问题,提出了一种基于四元数的改进型最小核值相似区(SUSAN)边缘检测算法。首先,利用四元数矢量旋转原理将HSI颜色空间... 详细信息

针对基于亮度和色度的彩色图像边缘检测在检测过程中忽略亮度和色度之间关联性而导致部分边缘不能有效地被检测出来的问题,提出了一种基于四元数的改进型最小核值相似区(SUSAN)边缘检测算法。首先,利用四元数矢量旋转原理将HSI颜色空间的三维信息映射成二维平面信息实现空间降维,同时引入标量V来综合表示H、S、I三通道之间的关系;然后,将标量V作为算子的核函数;最后,利用改进的SUSAN算子完成图像的边缘检测。实验结果表明,提出的算法针对色度相同、饱和度存在差异以及饱和度相同、色度存在差异的彩色图像,在边缘检测的定位误差率上降低了1.5%。在实际的应用中,能够更好地获得图像中的目标信息,同时也为后续的分割和识别研究提供更好的先验知识。

关键词：彩色图像四元数空间降维最小核值相似区边缘检测

幸存于幸存之中——小说《给未出生的孩子做安息祷告》的解析

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当代外国文学 2007年第4期28卷 82-87页

作者：宋健飞谢建文上海同济大学德语系上海外国语大学德语系

2002年匈牙利作家伊姆雷.凯尔泰斯荣获诺贝尔文学奖,作为二战期间大屠杀的幸存者,他的作品多以当年犹太人的命运为主题。《给未出生的孩子做安息祷告》是其重要作品之一,该小说融文学描写和哲思阐述于一炉,集中反映了作者复杂的心理和... 详细信息

2002年匈牙利作家伊姆雷.凯尔泰斯荣获诺贝尔文学奖,作为二战期间大屠杀的幸存者,他的作品多以当年犹太人的命运为主题。《给未出生的孩子做安息祷告》是其重要作品之一,该小说融文学描写和哲思阐述于一炉,集中反映了作者复杂的心理和对人生、世界与众不同的思考。

关键词：伊姆雷·凯尔泰斯《给未出生的孩子做安息祷告》犹太

Surgical treatment of primary tracheobronchial malignant tumors

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The Chinese-German Journal of Clinical Oncology 2010年第2期9卷 97-100页

作者： Hailong Wang Zhenzong Du Hua Ren Chaoji Zhang jianfei song Yuepei Liang Angui Li Min Zheng Department of Cardiothoracic Surgery Affiliated Hospital Guilin Medical College Guilin 541001 China Department of Cardiothoracic Surgery Peking Union Medical College Hospital Peking Union Medical College Beijing 100730 China

Objective： The aim of our study was to explore the clinical experience of surgical treatment for primary tracheobronchial malignant tumors. Methods： The clinicopathological data of 18 patients with primary tracheobronchial malignant tumors surgically treated from February 1994 to August 2007 were reviewed retrospectively. The surgical management included sleeve tracheal resection in 8 cases, lower trachea and carina resection with carina reconstruction in 4 cases, local enucleation of the tumor in 4 cases, left or right carino-pneumon-ection in 2 cases, and resection of the tracheal or bronchial tumor and reconstruction of the airway under cardiopulmonary bypass （CPB）in 6 cases. Results： Among the 18 cases, there were 7 adenoid cystic carcinomas, 9 squamous cell carcinomas, 1 lymphoepithelial-like carcinoma and 1 follicular non-Hodgkin tymphoma. All the cases recovered well except one who died of endotracheal bleeding and asphyxia at the 10th postoperative day. Conclusion： Surgical resection is the most effective treatment for primary tracheobronchial malignant tumors. The selection of operation modes should be individualized according to patients＇ condition. Both complete resection and safety should be taken into consideration simultaneously.

关键词： tracheobronchial tumor surgery cardiopulmonary bypass (CPB)

旋风分离器升气管外壁结焦厚度对分离器性能及后续结焦影响

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中国石油大学学报（自然科学版） 2023年第2期47卷 145-152页

作者：宋健斐赵建鹏魏耀东中国石油大学(北京)机械与储运工程学院北京102249 过程流体过滤与分离技术北京市重点实验室北京102249

以炼厂常用的PV型旋风分离器为研究对象,通过增加升气管壁厚的方法模拟结焦厚度增长,考察升气管外壁结焦厚度的增加对旋风分离器分离性能、流场及后续结焦情况的影响。结果表明:随着结焦厚度增加,旋风分离器压降小幅度降低但分离效率明... 详细信息

以炼厂常用的PV型旋风分离器为研究对象,通过增加升气管壁厚的方法模拟结焦厚度增长,考察升气管外壁结焦厚度的增加对旋风分离器分离性能、流场及后续结焦情况的影响。结果表明:随着结焦厚度增加,旋风分离器压降小幅度降低但分离效率明显降低;随着结焦厚度增加,旋风分离器环形空间的切向速度逐渐减小,轴向速度逐渐增大,升气管入口处的短路流逐渐增加;旋风分离器筒体段和锥体段的切向速度和轴向速度变化不明显;此外升气管外壁结焦厚度增加一方面会减小环形空间流体微元的向心加速度,进而减小颗粒向壁面黏附的几率,另一方面会增强对已黏附颗粒的清除作用,抑制结焦厚度的进一步增长。

关键词：旋风分离器结焦厚度分离效率压降流场

同方期刊数据库博看期刊评论

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180°矩形弯管流场的实验测量和数值模拟

化工学报 2007年第12期58卷 3033-3035页

作者：杜彩虹宋健斐魏耀东时铭显中国石油大学(北京)化工学院北京102249

The turbulent flow-field characteristics in a 180° curved duct with rectangular cross-section were *** profiles of tangential velocity and pressure were measured by using five-hole probe and simulated by FLUENT *** results showed that centrifugal force was generated as the fluid rotated,which contributed to the change of tangential velocity and *** velocity increased and pressure decreased in the section between 0° and 60° when the fluid rotation began,while tangential velocity decreased and pressure increased in the section between 60° and 180° near the inner *** the contrary,the tangential velocity decreased and pressure increased in the section between 0° and 60°,but tangential velocity increased and pressure decreased in the section between 60° and 180° near the outer *** investigation indicated that turbulent flow-field characteristics in the 180° curved duct could be understood by combined experiment measurement and numerical simulation.

关键词： 180°矩形弯管流场测量数值模拟