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1.
采用处理含有对力的推转壳模型(CSM)的粒子数守恒方法(PNC),研究了A-170区正常形变奇A核^171Yb的[521]1/2正常形变带的转动惯量随角频率变化的规律,在计算中同时考虑了单极对力与y五四极对力,并在PNC方法的计算中得到了非常好的重现,特别是来自每一个大壳和每一个推转的Nilsson轨道的贡献的微观机镧也得到了很好的展现。  相似文献   

2.
采用含有对力的推转壳模型(CSM)的粒子数守恒方法(PNC)研究正常形变奇A核^171Yb的[521]1/2带的单粒子轨道对转动惯量的贡献.同时考虑单极对力与四极对力,实验结果在PNC方法的计算中得到了较好的重现,特别是来自每一个大壳和每一个推转的Nilsson轨道的贡献的微观机制也得到了很好的展现。  相似文献   

3.
采用基于形变woods-Saxon势下的推转壳模型理论和处理对力的Lipkin-Nogami(LN)方法,研究了<'187>T1的形状共存问题.在自洽条件下,通过求解推转的LN方程得到了原子核总的位能面(TRS)图,证实了在<'187>T1核中的形状共存现象,得到了与实验一致的结果.  相似文献   

4.
应用公式W=Fscosθ计算力F所做功的条件是:在发生位移s的过程中,力F必须是大小、方向均不发生变化的恒力.在实际情况中,需要计算变力、未知力做功的情况比比皆足.下面通过对一些实际问题的求解,向同学们介绍一些计算变力与未知力(也适用于恒力)做功的方法.  相似文献   

5.
利用非线性有限元方法对谐波齿轮传动柔轮在弹性波发生器作用下变形与变形力进行了计算分析,得到:柔轮径向变形量与径向变形力的相关规律,柔轮初始变形力与柔轮形变基本成线性关系.计算结果与实验结果对比显示,两者趋势吻合.  相似文献   

6.
将D_2O分子固定在平衡构型下,得到了Ar-D_2O体系的三维势能面.在计算方法上,采用单双迭代(包括非迭代三重激发)耦合簇[CCSD(T)]理论,使用了扩展的相关一致基组aug-ccp VTZ,并且加入了(3s3p2d2f1g)中心键函数.结果显示体系有一个全局最小值,在R=6.91a0,θ=71.25°,φ=0°处,对应的势阱深度是138.7 cm-1,此时Ar-D_2O体系是一个平面结构.除了一个全局最小值,体系还有两个一阶鞍点和一个二阶鞍点.为了便于计算体系的束缚态能级,将势能展开成球谐函数的形式,采用3次样条插值的方法得到了径向展开系数vlm(R).通过求解薛定谔方程,得到体系的束缚态能级(J≤2),并在理论上预测了Ar-D_2O体系的微波谱及振转贯穿(VRT)谱,理论计算与实验吻合得很好.  相似文献   

7.
为了定量求解生物病变组织的杨氏模量,提出了一种基于边缘提取技术和图像配准技术的杨氏模量反演方法.在已知生物组织边缘位移及病变边缘的基础上,根据力的分布,构造单元系统,运用有限元反演方法(IFEM),计算出组织的杨氏模量.在此基础上估计全局杨氏模量范围,采用改进粒子群优化算法(PSO),计算出生物组织整体的杨氏模量分布.该算法克服了其他杨氏模量重建算法的限制,放松了对位移和边界力的要求.通过多次数值实验得出算法对存在误差的边缘位移同样有效;改进的PSO算法在较大范围内叠代搜索,总能向理论值靠近,并得到可行解.  相似文献   

8.
用非线性热力学方法,研究了外加应力及组分对外延单畴Pb(Zr1-xTix)O3(PZT)薄膜的相图及物理性质的影响.通过数值计算,得到了PZT薄膜在不同组分下的"外加应力-失配应变"相图.由相图可知,外加应力可以使薄膜发生铁电相变.在室温下,外加压应力能使薄膜的铁电相转变到顺电相.薄膜的压电系数对相变非常的敏感,施加一个适当的外加应力,可以大幅度提高压电系数.本文的计算结果,可以解释压痕仪和扫描力电镜研究铁电薄膜时所观察到的实验现象.  相似文献   

9.
用密度泛函理论(DFT)-B3LYP方法在6-31+G(d)基组水平上对间二甲苯的几何构型进行了全优化,得到几何构型参数,进一步对其振动光谱进行了计算.对计算得到的振动频率进行归属和解析并与文献值比较,发现理论计算得到的红外光谱与实验测定红外特征峰位较为吻合.这表明采用(DFT)-B3LYP方法能够预测芳烃类化合物的分子结构和红外光谱数据,从而为该类化合物光谱性质预测及构效关系研究提供依据.  相似文献   

10.
钟面角的计算问题,是同学们经常碰到的一类有趣的也是比较棘手的问题.本文拟从一般钟面角(特例)的计算中探究、归纳出计算公式,然后再分类举例说明其应用,望能对同学们有所帮助.一、钟面角计算公式的探究、归纳1.钟面角基本知识时钟的表面可看作一个圆,它被分成了12个大格,60个小格,由于一周角等于360°,所以每个大格对应30°的角,每个小格对应6°的角,又分针转一大格要5分钟,时针转一大格要60分钟,所以分针每分钟转6°,时针每分钟转(21)°.2.一般钟面角的计算与分析(特例分析)例1计算9点21分时,时针与分针的夹角.分析:12点时,时针与分针重…  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
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/  相似文献   

13.
《海外英语》2007,(5):10-11
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?  相似文献   

14.
The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.  相似文献   

15.
《海外英语》2007,(4):36
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.  相似文献   

16.
王菲 《华章》2007,(12):273-273
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.  相似文献   

17.
裴水妹 《华章》2007,(11):196
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.  相似文献   

18.
19.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

20.
风的曲线     
Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.  相似文献   

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