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1.
本文分析了重力对惯性秤频率(γ)的影响,导出了γ2-θ(倾角)函数关系,在理论和实验上定量地指明了如何测绘惯性秤的定标线。  相似文献   

2.
本文针对测惯性秤周期时计时点不易掌握、测量误差大的缺点,介绍了两种改进的方法.  相似文献   

3.
孟彬 《陕西教育》2010,(3):56-56
我国古代有两个脍炙人口的典故,一是“曹冲称象”,一是“司马光破缸救人”。在如何称象这个问题上,人们想到的只是称,因为自古以来,称小物用小秤,称大物用大秤,已是人人皆知的常理,而今没有足以称起大象的秤。因而无法计算。这是习惯性思维的必然结果,曹冲则不然,他利用了船的沉水深浅,用石头代替象。化整为零,终于秤出了象的体重。  相似文献   

4.
理论上计算弹簧质量对小振动系统的影响比较复杂,用焦利氏秤组装一小振动系统,通过对振动周期的多次测量,利用作图法并借助于MatIlenlatica数据处理程序对实验数据进行分析,可获得弹簧对小振动系统的质量影响因子,测量结果与理论值十分接近。  相似文献   

5.
两个刚性连接的电荷相对于某惯性系运动时,二之间具有相对论性作用力。即除了电场力还有磁场力产生.从理论上推导了这种力的具体表达式,得出了相应的结论。  相似文献   

6.
质点系的动量定理、动量矩定理和动能定理等基本定理,只能适用于惯性系。本在非惯性系中,考虑了每个质点所受到的惯性力,从牛顿第二定律出发,推导出了适用于非惯性系的质点系动力学基本定理。  相似文献   

7.
本文采用电热分离法、清水漂浮法和振动分离法对不同样本中甲螨的分离时间、数量,样本的放置时间及电热分离所用热光源作了比较。结果证实,分离土壤甲螨时.采土深度以10cm为宜,土壤放置7天与立即分离所获甲螨数无差别。少量土样直用清水漂浮法,大量土样宜用电热分离法。而植被样本宜用振动分离法。  相似文献   

8.
非惯性参照系中的Lagrange方程   总被引:2,自引:0,他引:2  
从非惯性参照系中的惯性力表达式出发,找出与之相对应的广义势函数U’,进一步写出与之相对应的类Lagrange函数表达式L″,从而推导出在非惯性参照系中的第二类Lagrange方程和保守力系的Lagrange方程,并通过实例说明在非惯性参照系中Lagrange方程的应用,从分析力学的角度提出了求解非惯性参照系中的动力学问题的一种方法。  相似文献   

9.
用振动法研究弹簧振子的有效质量和倔强系数   总被引:1,自引:1,他引:1  
这是一个改进型实验。该实验使用集成霍尔开关传感器,结合焦利氏秤用振动法求弹簧的倔强系数,并介绍了计算弹簧有效质量的一种方法。  相似文献   

10.
根据振动和力学理论,推导了梁构件在正弦扰力作用下共振时,梁上各点动应力的计算公式,为梁构件理论和实际问题的研究提供了一个有用的工具。  相似文献   

11.
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   

12.
汉字倒说     
汉字的六书,《说文》对“转注”一类,语焉不详。后世学者提及转注,也仅限于许慎所举出的例字。《汉字例说》一文,作者从转注的角度综合考虑,对部分现代常用字作了分析,跟传统的解释有所不同。希望能抛砖引玉,互相切磋,以推进学术研究。  相似文献   

13.
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   

14.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.  相似文献   

15.
《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   

16.
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   

17.
《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   

18.
Different nations have different social cultures, and the social culture of every nation is developing with the development of the nation, language is greatly influenced by social culture, which enables language to possess national and historical characteristics. Word is the smallest, independent, meaningful linguistic unit of language. It can well reflect the national and historical characteristics. From synchronic aspect, the social and cultural influence on word meaning is mainly embodied in conceptual and associative meanings of word. The incorrespondence of word meaning is a phenomenon that exists in both conceptual and associative meanings of word among different languages. From diachronic aspect, the development of social culture causes some changes of word meaning to some extent. Therefore, social culture plays a key role in vocabulary learning and mastery of a language.  相似文献   

19.
钱生钱!     
我们绝大部分人都同意一件事情——我们喜欢金钱。但是你对金钱的喜欢之情足够到让你创立一份事业么?.财富通常被人忽视,主要在于人们不能真正了  相似文献   

20.
The problem on the geometrc inequalities involving an n-dimensional simplex and its inscribed simplex is studied. Aninequality is established, which reveals that the difference between the squared circumradius of the n-dimensional simplex andthe squared distance between its circumcenter and barycenter times the squared circumradius of its inscribed simplex is not lessthan the 2(n-1)th power of n times its squared inradius, and is equal to when the simplex is regular and its inscribed siplex is atangent point one. Deduction from this inequality reaches a generalization of n-dimensional Euler inequality indicating that thecircumradius of the simplex is not less than the n-fold inradius. Another inequality is derived to present the relationship betweenthe circumradius of the n-dimensional simplex and the circumradius and inradius of its pedal simplex.  相似文献   

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