气液两相搅拌槽内气泡直径的数值模拟

搅拌槽内气泡直径是一个很重要的参数.本文对搅拌槽内气泡直径进行了数值模拟,模拟结果表明,在搅拌槽内排出流区和循环区内模拟值同实验值的吻合情况都比较好.在模拟过程中仅考虑了湍流动能耗散率对气泡大小的影响,没有考虑到气泡本身凝并和循环过程,所以在循环区中模拟值要比实验值稍大.     

钕离子注入硅晶体的横向离散研究

利用离子注入技术掺杂制作光电子器件时,需要了解离子注入材料的射程分布、射程离散和横向离散．介绍了用400keV能量的Nd离子分别垂直和倾斜60°角注入两块相同的Si晶体样品中,利用卢瑟福背散射技术研究了400keV,5×10^15ions／cm^2Nd离子注入Si晶体的横向射程离散．测出的实验值和TRIM’98得到的理论模拟值进行了比较,发现实验值跟TRIM’98模拟计算的理论值能较好地符合．     

二氧化碳冷冻刀冻融实验及数值模拟

实验研究了液体二氧化碳冷冻刀对机体组织造成的冷融过程，测定了组织内部的温度分布．实验对象为新鲜牛肉。对冷冻过程中机体组织内部的温度场和温度梯度进行了数值模拟，与实验结果吻合较好。研究工作为低温医疗手术中细胞冷冻损伤的研究提供了参考和依据。     

运用运动生物力学研究铅球运动的出手速度对运动成绩的影响

使用高速摄像对运动员的五次推铅球过程进行运动生物力学分析,运用力学分析和数学运算方法研究运动员推铅球的实际运动过程,验证铅球出手速度的合理性．结果表明,运动员出手速度对铅球的飞行距离有影响,实验值满足运动力学方程．     

实验原理的妙用

物理是以实验为基础的一门科学．实验是人们根据研究目的,利用科学仪器设备,设法控制或模拟物理现象,人为地排除次要因素,突出主要因素,在最有利的条件下,使物理现象反复再现而进行的观察研究的方法,让物理现象的本质更清楚地暴露出来,从而获得规律性的认识．因此在实验过程中,不仅需要创新,而且需要用理论来指导实验,再用实验来检验理论,     

批处理过程模拟系统的间歇过程模拟包的功能

通过分析研究批处理过程，采用了比较成熟的序贯模块法，把间歇过程连续化，开发了批处理过程的模拟系统．本文主要介绍了批处理过程模拟系统的间歇过程模拟包的结构及功能。并对具体实例进行了计算，结果与文献值相比误差不大。     

Fenton试剂脱除模拟印染废水色度的研究

以亚甲蓝水溶液做模拟印染废水,采用Fenton试剂氧化法对其进行处理,以水样吸光度作为评价指标,利用单因素优化及正交实验法,对Fenton试剂用量、反应时间和入水pH进行了系统的研究．实验结果表明,Fenton试剂氧化脱除模拟印染废水色度的效果明显,水样脱色率达到99％以上;随着Fenton试剂用量的增加以及反应时间的延长,水样色度去除率提高,适宜的Fenton试剂用量及反应时间分别为5mL试剂／25mL水样、30min;入水pH存在适宜值4,在入水pH由4降低N3和由4升高到6的过程中,水样色度去除呈现降低的趋势;Fenton试剂氧化模拟印染废水中,3因素影响大小顺序为：反应时间〉Fenton试剂用量〉入水pH．     

用PR方程直接模拟固体在超临界CO_2中溶解度

固体在超临界流体中的溶解度是设计超临界萃取过程的重要基础数据,状态方程PR方程常被用来计算这一数据。但该方程中的二元相互作用参数需要从实验数据回归得出,这就使该方程不能够推算固体在超临界流体中溶解度。本文用固体的热力学参数计算二元相互作用参数,不依赖实验数据,直接用PR方程模拟固体在超临界CO_2中的溶解度。计算结果表明,模拟值同实验值吻合较好。     

光弹实验在有限元建模中的应用

根据有限元软件计算出的应力值反演光弹条纹图,以对径受压圆环和紧凑拉伸试件为例研究应力集中区域网格疏密和网格形式对应力解的影响,并以三点弯梁为例研究边界条件对应力解的影响。对比有限元应力解模拟条纹图和实验条纹图,可得出只要网格划分合适,边界条件相符,模拟条纹图与实验条纹图能够非常吻合。此方法能够直观地反映出有限元建模过程中的模型和边界条件是否合理,并对其进行优化。     

模拟计算在大学物理实验教学中的应用

将模拟分析法引入传统大学物理实验中,有助于加深了学生对实验原理的理解,提高学生应用模拟分析方法解决实际问题的能力.文章介绍了模拟计算在物理实验中的应用,利用ANSYS软件对压电陶瓷超声波换能器、计算机机箱散热和磁场测量实验进行了模拟分析和谐响应分析,模拟计算值和实验测量值一致.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.