小学低年级语文识字教学浅议

语文是一门基础学科,而识字教学是基础中的基础.因此,在识字教学中,我们应培养孩子的识字能力,更应该培养孩子的识字兴趣,教给孩子识字方法,使我们的识字教学取得事半功倍的效率.     

大型回转窑修理及现场加工方法

利用回转窑自身旋转为动力现场修复托轮和窑体胎环(领圈),避免窑体后倾并保持平稳运行。延长了回转窑使用寿命,减少维修成本。     

The splitting of low-lying or low excited states for hydride molecules （cations） of the third period under spin-orbit coupling

This paper reports that the splitting of potential energy curves for the low-lying or low excited states for hydride molecules （cations） （MgH, AlH^＋, SiH, PH^＋, SH,ClH^＋） of the third period under Spin-Orbit Coupling has been calculated by using the Spin-Orbit Multi-Configuration Quasi-Degenerate Perturbation Theory （SO-MCQDPT） method. Then, spectroscopic constants of the split states have been derived from the Murrell-Sorbie function. The calculated dissociation energies for the spectrum branch terms have been given, respectively. The spectroscopic constants and dissociation energies for the spectrum branch terms are given for the first time in this paper.     

The splitting of low-lying states for hydroxyl molecule under spin--orbit coupling

The splitting of potential energy curves for the states $X^{2}\Pi _{3/2}$, $^{2}\Pi _{1/2}$ and $A^{2}\Sigma ^{ +}$ of hydroxyl OH under spin--orbit coupling (SOC) has been calculated by using the SO multi-configuration quasi-degenerate perturbation theory (SO-MCQDPT). Their Murrell--Sorbie (M--S) potential functions have been derived, then, the spectroscopic constants for $X^{2}\Pi _{3/2}$,$^{ 2}\Pi _{1/2}$ and $A^{2}\Sigma ^{ + }$ have been derived from the M--S function. The calculated dissociation energies for the three states are $D_{0}$[OH($X^{2}\Pi _{3/2})$]=34966.632cm$^{-1}$, $D_{0}$[OH($^{2}\Pi _{1/2})$]=34922.802cm$^{-1}$, and $D_{0}$[OH($A^{2}\Sigma ^{ + })$]=17469.794cm$^{-1}$, respectively. The vertical excitation energy $\nu [ {{ }^2\Pi _{1/2} ( {\nu = 0} ) \to {X}{ }^2\Pi _{3/2} ( {\nu = 0} )} ] = 139.6{\rm cm}^{-{\rm 1}}$. All the spectroscopic data for the $X^{2}\Pi _{3/2}$ and $^{2}\Pi _{1/2 }$ are given for the first time except the dissociation energy of $X^{2}\Pi _{3/2}$.     

胰腺癌的螺旋CT诊断价值

目的 探讨胰腺癌的螺旋CT扫描方法及诊断价值。方法 30例经手术病理及临床证实的胰腺癌患者进行Ⅲ期扫描。结果 胰腺实质期及门静脉期胰腺强化明显,肿瘤组织强化不明显。结论 胰腺实质期及门静脉期扫描诊断胰腺癌意义较大,延时期意义较小。     

颅内结节状及小环状强化的影像学研究与临床

目的 探讨颅内病变呈结节状及小环状强化的各自特点及鉴别要点。方法 追踪观察了268例在CT,MRI呈结节状及小环状强化的病例。结果 脑脓肿、炎性肉芽肿、结核瘤、脑囊虫病、胶质瘤及转移瘤等13种疾病可见结节状及小环状强化表现,并各有其特点。结论 通过观察影像学表现特点,结合病史及临床表现即可得出诊断。     

Imogolite类纳米管直径单分散性密度泛函理论研究

采用密度泛函理论方法研究了三种imogolite类(未取代、NH₂取代和F取代)纳米管的直径单分散性及表面电荷的分布情况, 并从键长方面定性地解释了直径单分散性的原因. 我们给出了IMO, IMO_NH₂和IMO_F的应变能曲线, 结果表明三种纳米管结构的最稳定管径值按照IMO < IMO_NH₂ < IMO_F的顺序递增, 而imogolite类纳米管直径单分散性是由于管径的增大导致内部Si–O, Al–O键与外部Al-OH键键长变化趋势相反造成的, 总之是内部Si–O, Al–O 键和外部Al–OH键相互作用的结果. 此外, 对三种稳定的纳米管结构做了Mulliken布局分析, 并总结了纳米管直径变化对表面电荷的影响. 结果表明正电荷主要积聚在外表面, 而内表面则感应出负电荷, 同时随着纳米管直径的增大表面电荷逐渐增加, 揭示了表面电荷与管径大小的关系. 研究表明, 可以通过改变imogolite内表面不同的官能化取代来控制纳米管直径, 进而调节表面电荷的分布情况, 这在imogolite类材料的分子设计及应用方面有着重要意义.     

Quasiclassical calculation of the chemical reaction Ba＋C3HTBr → BaBr＋C3H7

<正>The quasi-classical trajectory（QCT） method based on the extended London-Eyring-Polanyi-Sato potential energy surface is used to investigate the product vibrational distribution,angular distribution and angle-resolved kinetic distribution of the reaction Ba+C₃H₇Br→BaBr+C₃H₇ at 2.58 kcal/mol.The calculated results show that the product BaBr vibrational distribution is quite hot,the vibrational population peaks are located at v = 12,and the angular product distribution tends to backward scattering.The calculated angle-resolved kinetic distribution shows that the kinetic distribution is obviously related to angle.The QCT results are always qualitatively acceptable and sometimes even quantitatively.     

Quasiclassical calculation of the chemical reaction Ba+C3H7Br→BaBr+C3H7

The quasi-classical trajectory (QCT) method based on extended the London-Eyring-Polanyi-Sato potential energy surface is used to investigate the product vibrational distribution, angular distribution and angle resolved kinetic distribution of the reaction Ba+C₃H₇ Br→ BaBr+C₃H₇ at 2.58 kcal/mol. The calculated results show that the product BaBr vibrational distribution is quite hot, the vibrational population peaks are located at ν= 12, and the angular product distribution tends to backward scattering. The calculated angle resolved kinetic distribution shows that the kinetic distribution is obviously related to angle. The QCT results are always qualitatively acceptable and sometimes even quantitatively.     

空位缺陷对单层硅烯薄膜力学性能的影响

采用基于分子动力学理论的Forcite模拟软件包对含不同浓度的单、双空位缺陷硅烯薄膜的超晶胞体系进行优化,并对其力学性能进行了计算和分析.结果表明:随着空位缺陷浓度的增加,硅烯薄膜的拉梅常数、泊松比、体弹模量和剪切模量呈线性递减趋势,而由于空位缺陷附近键长的缩减导致硅烯薄膜"硬化"与空位缺陷浓度的增加导致硅烯晶格中硅原子密度降低,两种体制的竞争使得硅烯杨氏模量表现出先升高在降低的趋势.