用U(4)群研究氘代乙炔分子的振动激发态能谱

氘代乙炔分子的动力学对称群是三个U(4)群的直积群,找到一个适当群链,其中各子群的卡塞米尔算子组成分子的哈密顿,组合系数由该分子的实验光谱数据确定.利用这个代数哈密顿计算的能谱与实验值相符.实验上尚未观测的光谱也可以计算出来.     

大学化学综合实验教学实践——紫草药材提取实验

常见中药材紫草的主要活性成分为羟基萘醌类化合物,其具有多种药理作用。将紫草中羟基萘醌类化合物的提取引入有机化学基础实验课程,对于可变参数——提取时间和加醇倍量进行研究,学生自行设计并实施实验。该实验综合使用有机化学及分析化学实验基础操作的同时,提升学生学习兴趣,提高学生实验设计、数据处理及分析的能力。     

高校涉化类专业安全教育实效及提升策略研究——以天津理工大学为例

为考察高校涉化类专业安全教育实效,对天津理工大学化学化工学院670名学生进行问卷调查。问卷内容包括学生对化学专业的态度、兴趣、安全意识、安全经验、安全行为等。调查结果表明:安全意识方面,不同年级差异显著;化学恐惧和安全行为方面,不同性别差异显著;回归分析表明,安全意识/能力及化学兴趣与安全行为显著正相关。根据统计分析,提出以下提升策略:注重安全教育的持续性;关注学生心理安全;注意发挥学生的主观能动性。     

原子核间距对平行电磁场中He2+的回归谱与闭合轨道影响的研究

利用半经典闭合轨道理论和分区自洽迭代方法计算了Rydberg态下在平行电磁场中的回归谱与闭合轨道.通过计算分子中两原子之间的距离在平衡位置、最小以及最大时的闭合轨道和回归谱讨论了分子实散射效应对平行电磁场中的回归谱与闭合轨道的影响.     

Recurrence Spectra of the Rydberg Hydrogen Atom near Two Parallel Metal Surfaces

Using closed orbit theory, we study the influence of the two parallel metal surfaces on the recurrence spectra of a hydrogen atom placed in the region between the two surfaces. The results show that the metal surfaces have significant effect on the photoabsorption process. Each resonance peak in the recurrence spectra is associated with one electronic closed orbit. In our work, we put the first metal surface at the critical value dc and vary the second metal surface. The results show that when the distances between the hydrogen atom and the two metal surfaces are close to the critical valuedc, the number of the closed orbits is the greatest and there are more peaks in the recurrence spectra. When the distance between the atom and the second metal surface is larger or smaller than dc, the number of the closed orbits decreases and there are fewer peaks in the recurrence spectra. The agreement between the semiclassical calculation spectra and the quantum calculation spectra suggests that our analysis is correct.     

用小角X射线散射法研究CH2Cl2,CHCl3和CCl4对磷脂酰胆碱液晶态结构的影响机理

本文采用小角X射线散射法分别研究CH₂Cl₂,CHCl₃和CCl₄对磷脂酰胆碱液晶态结构的影响机理,通过比较得知,CH₂Cl₂,CHCl₃和CCl₄对磷脂酰胆碱液晶态结构影响的不同之处,主要是它们空间旋转电子云密度分布不同所致,空间旋转电子云密度分布呈球状或椭球状的物质都有使磷脂酰胆碱液晶形成片层六角形的机理,呈圆锥状的物质有诱发磷 关键词：     

我们是怎样提高金分析数据合格率的

在黄金生产和试验研究工作中,分析检验工作是重要环节,分析数据是核算经济指标的重要依据。冶金部黄金局在黄金矿山化验技术管理规则中规定:内检合格率达75%以上时基本分析结果为合格,否则基本分析结果全部作废。我们在金的分析中做了些工作,使金分析数据的合格率显著提高。平均合格率1981年为57.0%,1982年为81.3%,1983年为94.3%。为保证化验结果的准确度我们主要注意了以下几点;一、采用准确可靠的分析方法针对试样性质、特点采用相应的分析方法。在投入生产使用之前应作方法考核试验,以验证方法的可靠性和熟悉关键操作,以便正确掌握分析方法。二、采样必须有代表性严格遵守并使用合理的     

Dynamics of a Rydberg Hydrogen Atom in a Generalized van der Waals Potential and a Magnetic Field

The classical dynamics of a Rydberg hydrogen atom in a generalized van der Waals potential plus a magnetic field is investigated by using the Poincaré surface of section and phase space trajectories method. The dynamical character of this system depends sensitively on the magnetic field strength. The numerical calculations show that for a certain van der Waals potential, its classical dynamics is regular without the external magnetic field. However, with the addition of the external magnetic field, the dynamical property of the Rydberg hydrogen atom begins to change. With the increase of the magnetic field strength, order-chaos-order-chaos types of transition regions are observed for the hydrogen atom. As the magnetic field strength is very large, nearly all the phase space trajectories are chaotic. Under this condition, only chaotic motion appears. This is caused by the diamagnetic Zeeman effect. Our study provides a different perspective on the dynamical behavior of the Rydberg atom in the van der Waals potential and magnetic field.     

Theoretical Study of the Influence of Femtosecond Laser Wavelength on the Evolution of a Double-Minimum Electronic Excited State Wave Packet for NaRb

Employing the two-state model and the time-dependent wave packet method, the influence of femtosecond laser wavelength on the evolution of the double-minimum electronic excited state wave packet is numerically investigated. For different laser wavelengths, evolutions of the double-minimum electronic excited state wave packet with time and internuclear distance are different. One can control the evolution of the wave packet by varying the laser wavelength appropriately, which will benefit the light manipulation of atomic and molecular processes. Furthermore, study of the dynamics of the NaRb molecule may yield clues to creating an ultracold molecule.