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1.
Mn-W co-doped ZnO(ZMWO) thin films with low resistivity and high transparency were successfully prepared on glass substrate by direct current(DC) magnetron sputtering at low temperature.The sputtering power was varied from 65 to 150 W.The crystallinity and resistivity of ZMWO films greatly depend on sputtering power while the optical transmittance and optical band gap are not sensitive to sputtering power.All the deposited films are polycrystalline with a hexagonal structure and have a preferred orientat...  相似文献   
2.
Highly transparent and conducting Al-Zr co-doped zinc oxide (ZAZO) thin films were successfully prepared on glass substrate by direct current (DC) magnetron sputtering at room temperature.The distance between target and substrate was varied from 45 to 70 mm.All the deposited films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate.The crystallinity increases obviously and the electrical resistivity decreases when the distance betwe...  相似文献   
3.
地铁接触网失电故障会导致线路运营中断,影响乘客出行,所以对此状态下的运营交路设计十分必要。文章以南京地铁二号线2A3及2C3A、2B3及2C3B接触网供电分区失电故障为例,依据交路设计的原则,采取“先通后复”的方式优先变更交路,结合列车运行LZ043时刻表,以最大限度降低故障造成的延误为前提,对所设计交路的运行周期、行车间隔及上线列车数等数据予以现场验证,提出运营调整的关键措施,为地铁科学、高效地组织列车运行提供一定的参考建议。  相似文献   
4.
采用直流磁控溅射法在玻璃衬底上制备了高质量的Nb掺杂ZnO( NZO)透明导电薄膜.为了研究薄膜厚度对薄膜性质的影响,制备了五个厚度分别为239 nm,355 nm,489 nm,575 nm和679 nm的样品.XRD结果表明,ZnO∶ Nb薄膜是具有六角纤锌矿结构的多晶薄膜,并且具有垂直于衬底的c轴择优取向.随着膜厚的增加,薄膜的结晶质量明显提高.当厚度从239 nm增加到489 nm时,平均晶粒尺寸从19.7 nm增加到24.7 nm,薄膜的电阻率持续减小;当厚度进一步增加时,晶粒尺寸略有减小,电阻率有所增加.本实验获得的最低电阻率为4.896×10-4Ω·cm.随膜厚的增加,光学带隙先增大后减小.所有薄膜在可见光区域的平均透过率均超过88.3;.  相似文献   
5.
利用直流磁控溅射法在玻璃衬底上制备了铝铬共掺杂氧化锌(ZACO)透明导电薄膜.通过X射线衍射(XRD)和扫描电镜(SEM)等表征方法对薄膜特性进行测试分析,研究了溅射压强和溅射功率对薄膜生长速率以及光电特性的影响.结果表明,随着溅射气压(1.5~4.5 Pa)的增大,薄膜沿c轴方向的结晶质量提高,薄膜表面更加致密,晶粒大小更加均匀.薄膜生长率随压强的增大而减小,但电阻率先减小后增大.当溅射功率由80 W增大到100 W时,薄膜的生长速率增大,电阻率减小.溅射压强为3.5 Pa,溅射功率为100 W时,薄膜的电阻率达到最小值2.574×10-3 Ω·cm.紫外-可见透射光谱表明,所有薄膜在可见光区的透过率均超过89.9;.  相似文献   
6.
利用直流磁控溅射法成功地在室温玻璃衬底上制备出了电阻率低、透光率高的Mn-W共掺ZnO(ZMWO)透明导电薄膜。溅射功率在65-150 W之间变化。实验结果表明,溅射功率对ZMWO薄膜的晶化程度和电阻率有很大影响,而对其透光率和光学带隙影响不大。实验制备的ZMWO为六方纤锌矿结构的多晶薄膜,具有垂直于衬底方向的c轴择优取向。考虑到薄膜的电学、光学性能及结晶质量,我们认为本实验中的最佳值溅射功率为90 W,在此功率下制备的ZMWO薄膜的电阻率具有最小值9.8×10-4Ωcm,其可见光透过率为89%。  相似文献   
7.
室温下,采用直流磁控溅射法,在玻璃衬底上制备出Nb掺杂ZnO(NZO,ZnO:Nb)透明导电薄膜。研究了靶与衬底之间的距离对NZO薄膜结构、形貌、光学及电学性能的影响。实验结果表明,不同靶基距下制备的NZO薄膜均为c轴择优取向生长,(002)衍射峰的强度随着靶基距的减小而增大。靶基距增大时,薄膜表面逐步趋向平整光滑、均匀致密,薄膜的厚度逐渐减小。在靶基距为60mm时,制备的薄膜厚为355.4nm,电阻率具有最小值(6.04×10-4Ω.cm),在可见光区的平均透过率达到92.5%,其光学带隙为3.39eV。  相似文献   
8.
室温下,利用直流磁控溅射法在玻璃衬底上制备了铝铬共掺杂氧化锌薄膜,研究了溅射功率(55-130 W)对薄膜结构、残余应力、表面形貌及其光电性能的影响。结果表明,ZnO(002)衍射峰的强度随着溅射功率的增大而增强,晶体结构得以改善。晶格常数、压应力和电阻率均随着溅射功率的增大而减小。当溅射功率为130 W时,制备的ZnO∶Al,Cr薄膜的最低电阻率可达1.09×10-3Ω.cm。功率由55 W增大到130 W时,光学带隙由3.39 eV增大到3.45 eV。紫外-可见透射光谱表明,所有薄膜在可见光范围内平均透过率均超过89%。  相似文献   
9.
Magnetic Instability in Accretion Disks with Anomalous Viscosity   总被引:1,自引:0,他引:1       下载免费PDF全文
Using the new model of anomalous viscosity, we investigate the magnetic instability in the accretion disks and give the dispersion formula. On the basis of the dispersion relation obtained, it is numerically shown that the instability condition of viscous accretion disk is well consistent with that of the ideal accretion disk, namely there would be magneto-rotational instability in the presence of a vertical weak magnetic field. For a given distance R from the centre of the disk, the growth rate in the anomalous case deviates from the ideal case more greatly when the vertical magnetic field is smaller. The large viscosity limits to the instability. In the two cases, the distributions of growth rate with wave number κ approach each other when the magnetic field increases. It greatly represses the effect of viscosity.  相似文献   
10.
Based on the Ising spin, the phase transition on fractal scale-free networks with tree-like skeletons is studied, where the loops are generated by local links. The degree distribution of the tree-like skeleton satisfies the power-law form P(k)~ k~(-δ).It is found that when δ≥3, the renormalized scale-free network will have the same degree distribution as the original network. For a special case of δ = 4.5, a ferromagnetic to paramagnetic transition is found and the critical temperature is determined by the box-covering renormalization method. By keeping the structure of the fractal scale-free network constant, the numerical relationship between the critical temperature and the network size is found, which is the form of power law.  相似文献   
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