排序方式: 共有60条查询结果,搜索用时 125 毫秒
11.
利用X光电子能谱(XPS)和高分辨电子能量损失谱(HREELS)研究了几种条件下LiF和Al的化学反应.在有Alq3参与的情况下,LiF和Al在室温下发生反应.在Al/LiF/Alq3系统中,Li 1s的峰发生了0.25 eV的位移,同时F 1s也发生了相应的位移.在没有Alq3参与的情况下,加热样品至350 K后,在Li 1s峰的低能端0.85 eV处出现了一个伴峰.XPS研究表明,这个伴峰对应的是金属态的Li 1s.HREELS的结果也验证了这一结论. 相似文献
12.
利用紫外光电子谱 (UPS)对乙烯 (C2 H4)和乙炔 (C2 H2 )气体在Ru(10 10 )表面的吸附及与K的共吸附进行了研究 ,实验结果表明 :当衬底温度超过 2 0 0K ,乙烯即发生脱氢反应后 ,σCH 和σCC 能级均向高结合能方向移动 .在室温下 ,σCH和σCC 能级位置与乙炔在Ru(10 10 )表面的吸附时的分子能级完全一致 .乙烯发生脱氢反应后的主要产物为乙炔 .衬底温度从 12 0K升到室温 ,Ru(10 10 )表面上乙炔的σCH 和σCC 能级均未发现变化 .室温下乙炔仍然可以在Ru(10 10 )表面以分子状态稳定吸附 .在有K的Ru(10 10 )表面上 ,室温时σCC谱峰几乎消失 .碱金属K的存在促进了乙炔的分解 . 相似文献
13.
14.
用热脱附谱等方法研究了NO分别在清洁和Cs覆盖的Ru(10^-10)表面上的吸附。结果表明:存在两种NO分子吸附态(a1,a2),脱附温度分别处于325℃和550℃附近。Cs的存在增加了Ru(10^-10)表面上a2态的吸附位置,提高了该态的脱温度。Cs在Ru(10^-10)表面的存在同时促进了吸附NO分子的分解。NO在Ru(10^-10)表面上分解后形成吸附O原子和N原子。N原子复合以N2在约5 相似文献
15.
16.
17.
利用紫外光电子谱(UPS)对乙烯(C2H4)和乙烯(C2H2)气体在Ru(1010)表面的吸附及与K的共吸附进行了研究,实验结果表明:当衬底温度超过200K,乙烯即发生脱氢反应后,σCH和σCC能级均高结合方向移动.在室温下、σCH和σCC能级位置与乙炔在Ru(1010)表面的吸附时的分子能级完全一致.乙烯发生脱氢反应后的主要产物为乙炔。衬底温度从120K升到室温,Ru(1010)表面上乙炔的σCH和σCC能级均未发现变化.室温下乙炔仍然可以在Ru(1010)表面以分子状态稳定吸附.在有K的Ru(1010)表面上.室温时σCH谱峰几乎消失.碱金属K的存在促进了乙炔的分解. 相似文献
18.
利用镜像电荷模型,对静电场中单根纳米导线尖端的电势和电场进行计算,得到纳米导线发射体尖端场增强因子表达式为β0=h/ρ+35. 若考虑极板间距对场增强因子的影响,则场增强因子的表达式调整为β=〖SX(〗h〖〗ρ〖SX)〗+35+A〖JB((〗〖SX(〗h〖〗d〖SX)〗〖JB))〗3,其中h,ρ分别为纳米导线的长度和半径,d为极板间距,A为常数. 结果表明纳米导线的长径比对场增强因子的影响最显著,而极板间距对纳米导线的场增强因子只有微弱影响,随极板距离的增加而减小.
关键词:
纳米导线
场发射
增强因子
极板间距 相似文献
19.
We prepare a well-defined C84 monolayer on the surface of Ag (111) and study the geometric structure by scanning tunneling microscopy (STM). The C84 molecules form a nearly close-packed incommensurate R30° lattice. The lattice is long-distance ordered with numerous local disorders. The monolayer exhibits complex bright/dim contrast; the largest height difference between the molecules can be greater than 0.4 nm. Annealing the monolayer at 380 ℃ can desorb part of the molecules, but more than sixty percent molecules stay on the Ag (111) surface even after the sample has been annealed at 650 ℃. Our analyses reveal that the 7-atom pits form beneath many molecules. Some other molecules sit at the 1-atom pits. Ag adatoms (those removed substrate atoms, accompanying the pit formation) play a very important role in this system. The adatoms can either stabilize or destabilize the monolayer, depending on the distribution manner of the adatoms at the interface. The distribution manner is determined by the co-play of the following factors: the dimension of the interstitial regions of the C84 overlayer, the number of the adatoms, and the long-distance migration of part adatoms. 相似文献
20.
This paper reports that Eu-doped ZnO films were successfully deposited on silicon (100) by radio-frequency magnetic sputtering. The x-ray diffraction patterns indicate that Eu substitutes for Zn in the lattice. Ferromagnetic loops were obtained by using superconducting quantum interference device at 10 K and room temperature. No discontinuous change was found in both of the zero-field-cooled and field-cooled curves. The observed ferromagnetism in Eu-doped ZnO can be attributed to a single magnetic phase. The saturation magnetisation decreased remarkably for the Eu-doped ZnO prepared by introducing 5% of oxygen in the sputtering gas or by the post annealing in O2, suggesting that the defects play key roles in the development of ferromagnetism in Eu-doped ZnO films. 相似文献