Field Emission from Silicon Nanocrystallite Films with Compact Alignment and Uniform Orientation

Patterned silicon nanocrystallite (SINC) films were fabricated on (100) orientation p-type boron-doped sificon wafer by the hydrogen ion implantation technique and the anodic etching method. The efficient field emission with low turn-on field of about 3.5V/μm at current density of 0.1μA/cm^2 was obtained. The emission current density from the SiNC films reached 1mA/cm^2 under a bias field of about 9.1V/μm. The experimental results demonstrate that there are great potential applications of the SiNC films for fiat panel displays. A surface treatment with hydrogen plasma was performed on the SiNC films and a significant improvement of emission properties was achieved.     

Effect of Incident Intensity on Films Growth in Pulsed Laser Deposition

Incident intensity, defined by the amount of particles deposited per pulse, is an important parameter in the film growth process of pulsed laser deposition （PLD）. Different from previous models, we investigate the irreversible and reversible growth processes by using a kinetic Monte Carlo method and find that island density and film morphology strongly depend on pulse intensity. At higher pulse intensities, lots of adatoms instantaneously diffuse on the substrate surface, and then nucleation easily occurs between the moving adatoms resulting in more smaller-size islands. In contrast, at the lower pulse intensities, nucleation event occurs preferentially between the single adatom and existing islands rather than forming new islands, and therefore the average island size becomes larger in this case. Additionally, our results show that substrate temperature plays an important role in film growth. In particular, it can determine the films shape and weaken the effect of pulse intensity on film growth at the lower temperatures by controlling the mobility rate of atoms. Our results can match the related theoretical and experimental results.     

关于新旧教材比较及对教学的启迪--以万有引力定律教学为案例

l比较新旧教材的意义 对教师而言，比较新旧教材，无疑是教学活动中不可缺少的环节．通过新旧教材的对比，可以使教师掌握教材编排．更重要的是，通过新旧教材对比，让教师更好地领会新旧教材的不同，进而了解编者的意图，体会新课程标准的理念，从而在教学活动中更好地理解和落实新课程标准．下面，笔者以2004年初审通过的广东教育出版社出版的《普通高中课程标准实验教科书物理（必修2）》第三章第一节“万有引力定律”，     

一类具有二维分叉方程的积分方程的分叉

本文研究一类含参数的非线性积分方程的分叉问题,其中的积分算子的线性化算子在分叉值点处有二维零空间。利用Liapunov-Schmidt约化方法和基于系统的对称性的群论方法,得到了周期分叉解存在的充分条件。     

Numerical Study on Left-Handed Materials Made of Ferrite and Metallic Wires

Due to coupling effect, we show that it is difficult to realize the left-handed material by placing metallic wires directly into a ferrite matrix. However by introducing an insulating material round the metallic wires to decouple the direct interaction between the metallic wire and ferrite matrix, we have proposed two microstructures, which are shown by numerical simulation to have negative refractive indexes. The influence of microstructure on the transmission property is also examined.     

有界域上具有离散全纯核的Koppelman公式与-方程

D是Cn空间中具有逐块C(1)边界的有界域,该文建立了D上一个具有离散局部全纯核的 (0,q)形式的Koppelman积分公式及其相应的■-方程解的积分表示和它的内闭一致估计式.     

第32届国际数学奥林匹克试题及解答

1.(苏联提供)已给△ABC,设I是它的内心,角A,B,C的内角平分线分别与其对边交于A′,B′,C′。求证     

有界域上具有离散全纯核的Koppelman公式与方程

D是C^n空间中具有逐块C(1)边界的有界域，该文建立了D上一个具有离散局部全纯核的(0，q)形式的Koppelman积分公式及其相应的方程解的积分表示和它的内闭一致估计式。