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本文研究了用四氟化碳-氧等离子体进行干法显影的电子束刻蚀技术。负型电子束抗蚀剂是由聚环己烯砜和2,6-双-(4'-叠氮苯亚甲基)-4-甲基环己酮组成,其灵敏度为1.5×10-5C/cm2,分辨率小于1μm,反差约1.43。并讨论了干法显影的影响因素和机理。  相似文献   
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本文从实验上研究了起始粉料的制备方法和热压条件对磁头用的Mn-Zn及Ni-Zn热压铁氧体的密度、显微结构和磁性的影响。实验结果表明,化学共沉淀法制备的铁氧体粉料比氧化物法及硫酸盐法制备的要好。适当选择热压条件,可以获得晶粒分布均匀、晶粒大小不同(10μm—300μm)的高密度铁氧体;可以获得μ0=7420以及Bm=4950Gs的高密度Mn-Zn铁氧体和μ0等于100—2500的高密度Ni-Zn铁氧体。  相似文献   
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The friction and wear performance of pure polycarbonate (PC) and 2.5, 5, 10, and 30% zinc borate-filled (by wt) PC composites were comparatively evaluated under dry sliding conditions. Wear tests were performed at room temperature under the loads of 5, 10, and 20?N and at the sliding speeds of 0.5, 1.0, and 1.5?m/s. The coefficients of friction of the composites were significantly influenced by an increase in zinc borate content. The friction coefficient of PC was decreased from 0.457 to 0.160 with an increase in zinc borate content, depending on applied loads and sliding speeds. The results showed that the wear rates of pure PC and zinc borate-filled composites decreased with an increase in loads. The wear rates of zinc borate-filled composites were significantly affected from zinc borate content. The wear rate of PC decreased from 9.4?×?10?5 to 6.8?×?10?6?mm3/m with an increase in zinc borate content depending on applied loads.  相似文献   
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In this work, we present first principles calculations based on a full potential linear augmented plane-wave method (FP-LAPW) to calculate structural and electronic properties of CdX and ZnX (X = S, Se, Te) based II–VI chalcogenides. First principles calculations using the local density approximation (LDA) and the related generalized gradient approximation (GGA) lead to a severe underestimate of the band gap. The proposed model uses various exchange–correlation potentials (LSDA, GGA and MBJLDA) to determine band gaps and structural properties of semiconductors. We show that using modified Becke–Johnson (MBJLDA) density potential leads to a better agreement with experimental data for band gaps of Cd and Zn based semiconductors.  相似文献   
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We examined the stationary state solutions of a bond diluted kinetic Ising model under a time dependent oscillating magnetic field within the effective-field theory (EFT) for a honeycomb lattice (q=3). The effects of the Hamiltonian parameters on the dynamic phase diagrams have been discussed in detail. Bond dilution process on the kinetic Ising model causes a number of interesting and unusual phenomena such as reentrant phenomena and has a tendency to destruct the first-order transitions and the dynamic tricritical point. Moreover, we have investigated the variation of the bond percolation threshold as functions of the amplitude and frequency of the oscillating field.  相似文献   
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以大孔型苯乙烯系三丁胺胺化强碱性阴离子交换树脂为催化剂,催化苯乙腈的α-丁基化反应,研究了反应温度,催化剂用量和反应时间等因素对反应产率的影响。并考察了催化剂的重复使用性能,结果表明:在优化条件下,该催化剂催化苯乙腈的α-丁基化反应产率高达88%以上,且催化剂具有良好的重复使用性能。  相似文献   
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In this work, we present a second nearest neighbour sp3s* semi-empirical tight-binding theory to calculate the electronic band structure of heterostructures based on group III-N binary semiconductors and their ternaries. The model Hamiltonian includes the second nearest neighbour (2nn) interactions, the spin–orbit splitting and the nonlinear variations of the atomic energy levels and the bond length with ternary mole fraction. Using this sp3s* tight-binding approach, we investigated the electronic band structure of Al1−xGaxN/GaN and In1−xGaxN/GaN heterostructures as a function of composition and interface strain for the entire composition range (0≤x≤1). There is an excellent agreement between the model predictions and experiment for the principal bandgaps at Γ, L and X symmetry points of the Brillouin zone for AlN, GaN and InN binaries and Al1−xGaxN and In1−xGaxN ternaries. The model predicts that the composition effects on the valence band offsets is linear, but on the conduction band offsets is nonlinear and large when the interface strain and deformation potential is large.  相似文献   
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本文对钕玻璃的光泵感应热畸变作了理论分析,给出了光泵感应热畸变与钕玻璃热光性质的关系,并对高重复率脉冲器件和单次脉冲器件作了热畸变的定量测量,实验结果在一定程度上与理论分析相符。  相似文献   
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