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1.
本文提出一种新的描述金属卤化物标准生成焓H的键参数函数,即用电荷数z与半径r之比、电负性x、主量子数n研究了它们与金属卤化物标准生成焓H的相关性,用MATLAB语言算得相关系数为R=0.9910.结果表明金属卤化物生成焓与z/r、x、n有很好的线性关系,其线性回归方程如下:△H=696.6372 45.4539[z1/r1/0.77)^2 z2/(r2/0.77)^2] 25.8218n^1/3-453.5393x  相似文献   

2.
通过对烯烃分子结构及其气态标准生成焓实测数据的分析,建立了结构信息指数Pi(i=1,2,3,4),Xi,Yu(i=1,2;j=2,3,…,n—1),并计算了50种烯烃的信息指数.在此基础上利用SPSS软件对信息指标进行因子分析,计算出因子得分,将因子当作自变量给出多元回归方程,并对50种烯烃的气态标准生成焓进行预测,结果令人满意.  相似文献   

3.
由气态原子标准生成焙和键培,计算了9个杂环化合物的气态标准生成焓,所得结果与实验结果相吻合.还用HMO方法计算了它们的共振能,并讨论了共振能、键焓对标准异构化焓的影响.  相似文献   

4.
合成了硝酸铈与丙氨酸的稀土氨基酸配合物Ce(Ala)4(NO3)3·H2O(s)。用具有恒温环境的反应热量计在298.15K测定了Ce(Ala)4(NO3)3·H2O(s)在水中的溶解焓△aHm=-3.268±0.022kJ·mol^-1,并计算出配离子Ce(Ala)4^3+(aq)在298.15K时的标准生成焓△fHm^θ[Ce(Ala)4^3+,aq,298.15K]=-3030.9kJ·mol^-1。  相似文献   

5.
通过电负性X和有效主量子数n*定义了有效价电子数Zi,用于计算了元素键参数扑指数,用该元素键参数拓扑指数与卤化物标准生成焓,标准自由能做相关性研究。得到了标准生成焓,标准自由能依赖元素键参数拓扑指数的线性方程,相关性良好。  相似文献   

6.
当前硝酸镝与丙氨酸配离子的标准生成焓未见文献报道。本文合成了硝酸镝与丙氨酸的稀土氨基酸配合物Dy(Ala)4(NO3)3·H2O。采用具有恒温环境的反应热量计,在298.2K时,测定了Dy(Ala)4(NO3)3·H2O在水中的溶解焓,根据热化学原理计算出配离子Dy(Ala)]4^3+在298.2K时的标准生成焓△Hif,m^8,[Dy(Ala)4^3+,aq,298.2K]=-2920.6410·mol^-1。  相似文献   

7.
硝酸铒与丙氨酸配离子的标准生成焓未见文献报道。本文合成了硝酸铒与丙氨酸的稀土氨基酸配合物Er(Ala)4(NO3)3·H2O。采用具有恒温环境的反应热量计,在298.2K时,测定了Er(Ala)4(NO3)3·H2O在水中的溶解焓△8Hm^θ,=7.346±0.17kJ·mol^-1,根据热化学原理计算出配离子Er(Ala)4^3+在298.2K时的标准生成焓△Hf,m^θ[Er(Ala)4^3+,aq,298.2K]=-2910.02kJ·mol^-1。  相似文献   

8.
合成了硝酸铈与丙氨酸的稀土氨基酸配合物Ce(Ala)4(NO3)3·H2O(s)。用具有恒温环境的反应热量计在298.15K测定了Ce(Ala)4(NO3)3·H2O(s)在水中的溶解焓△aHm=-3.268±0.022kJ·mol^-1,并计算出配离子Ce(Ala)4^3+(aq)在298.15K时的标准生成焓△fHm^θ[Ce(Ala)4^3+,aq,298.15K]=-3030.9kJ·mol^-1。  相似文献   

9.
由气态原子标准生成焓和键焓,计算了9个杂环化合物的气态标准生成治,所得结果与实验结果相吻合.还用HMO方法计算了它们的共振能,并讨论了共振能、键焓对标准异构化焓的影响.  相似文献   

10.
与Smarandache双阶乘对偶函数有关的方程   总被引:1,自引:1,他引:0  
对任意的正整数n,S^**(n)表示Smarandaehe双阶乘对偶函数,Ф(n)表示Euler函数.利用初等方法研究方程S^**(n)=n,(S^**(n))^2=2n及S^**(n)=Ф(n)的可解性,并给出了每个方程所有正整数解.  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.
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   

13.
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   

14.
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   

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.
《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   

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