判断原子态有无磁矩的方法

介绍一种直接判断朗德g因子是否为零的方法，从而可方便地判断原子态是否有磁矩，同时讨论了g=0时的原子矢量模型，最后指出原子能级在外磁场中是否分裂的条件。     

g因子取负值的讨论

本文讨论了各种耦合情况下原子部分g因子为负值的条件,并说明由此可能产生的影响.     

什么样的原子态在外磁场中能级不分裂

:用代数方法和矢量图示几何法分析什么样的原子态在外磁场中能级不分裂 ,得出了朗德因子g =0时 ,描述原子态的三个量子数L、S、J之间的关系 ,指出了原子态在外磁场中能级不分裂的实质     

什么样的原子态在外磁场中能级不分裂

用代数方法和矢量图示几何法分析什么样的原子态在外磁场中能级不分裂，得出了朗德因子g=0时，描述原子态的三个量子数L、S、J之间的关系，指出了原子态在外磁场中能级不分裂的实质。     

卤素的原子电负性与分子电负性的关系

通过MP2/6-31g(d,p)、MP2/6-311g(3df,3pd)、B3LYP/6-311g(3df,3pd)方法计算氟、氯、溴原子和分子、原子及分子的阳离子和阴离子的能量。用MP2/lanl2dz方法计算碘原子和分子、原子及分子的阳离子和阴离子能量。由计算得出的能量分析得出氟、氯、溴、碘原子和分子的电负性。结果表明:不同方法计算得出的卤素原子和分子的电负性数值变化规律相同,由此可以得出卤素原子的电负性可以近似描述由相同原子组成的双原子分子体系。     

朗德因子的取值范围

本文从LS耦合下朗德因子的表达式出发，给出理论上原子朗德因子的取值范围。     

高中化学解选择题的一些策略

一、善用“阿伏加德罗常数” 例1 碳元素的相对原子质量为12,^12C原子的质量为6g,A原子的质量为αg,阿伏加德罗常数为NA,则A相对原子质量为（ ）     

原子电负性和共价半径的规律性研究

原子电负性和共价半径各自具有周期性的变化规律，自Pauling首次提出电负性概念之后，已有许多作者提出原子电负性的计算法，本篇总结和分析了种种上电负性的标度，引入一个新的原子参数W，其值可通过周期因子计算，再根据X＝W／r可以计算各原子的电负性。     

侯氏制碱法中的绿色化学思想

本文依据索尔维制碱法和侯氏制碱法的化学反应,计算了两种制碱方法的原子利用率和E因子,从绿色化学原则和原子经济性的角度讨论了侯氏制碱法的绿色化学思想,证明了侯氏制碱法是原子利用率为百分之百、没有副产物、实现了零排放的理想原子经济反应。     

火焰原子吸收法测定海带中的铁、钙和钴

目的研究测定海带中对人体有益的微量元素含量的新方法.方法用灰化法溶解试样,配制标准系列溶液,采用空气-乙炔火焰原子吸收法测定海带中铁、钙和钴三种微量元素含量.结果海带中含Ca为1.77mg/g,Fe为538μg/g,Co为22μg/g,加标回收率在97%-103%,同一样本平行测定7次的相对标准差小于5%.结论利用火焰原子吸收测定海带中的铁、钙和钴的分析方法准确可靠.     

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?     

Western and Eastern culture differences in commercial field

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.     

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.     

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.     

团图为数的图中的闭团贯数

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.     

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.