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951.
We created mixed triatomic clusters, AlCGe(-), AlSi(2)(-), and AlGe(2)(-), and studied their electronic structure and chemical bonding using photoelectron spectroscopy and ab initio calculations. Excellent agreement between theoretical and experimental photoelectron spectra confirmed the predicted global minimum structures for these species. Chemical bonding analysis revealed that the AlSi(2)(-) and AlGe(2)(-) anions can be described as species with conflicting (sigma-antiaromatic and pi-aromatic) aromaticity. The AlCGe(-) anion represents an interesting example of chemical species which is between classical and aromatic. 相似文献
952.
Efficient synthetic approaches to higher para-dihydroquinones and -quinones have been developed through zirconium/CuCl-mediated cycloaddition reactions of two alkynes and quinone in a one-pot procedure. 相似文献
953.
Xijun Deng Jinlong Cao Xi Li 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):281-290
In this paper, travelling wave solutions for the nonlinear dispersion Drinfel’d–Sokolov system (called D(m,n) system) are studied by using the Weierstrass elliptic function method. As a result, more new exact travelling wave solutions to the D(m,n) system are obtained including not only all the known solutions found by Xie and Yan but also other more general solutions for different parameters m,n. Moreover, it is also shown that the D(m,1) system with linear dispersion possess compacton and solitary pattern solutions. Besides that, it should be pointed out that the approach is direct and easily carried out without the aid of mathematical software if compared with other traditional methods. We believe that the method can be widely applied to other similar types of nonlinear partial differential equations (PDEs) or systems in mathematical physics. 相似文献
954.
In this paper we show that the leading coeficient μ(y,w) of some Kazhdan-Lusztig polynomials Py,w with y,w in an affine Weyl group of type n is n + 2.This fact has some consequences on the dimension of first extension groups of finite groups of Lie type with irreducible coefficients. 相似文献
955.
Generalized Petersen graphs are commonly used interconnection networks,and wide diameter is an important parameter to measure fault-tolerance and efficiency of parallel pro- cessing computer networks.In this paper,we show that the diameter and 3-wide diameter of generalized Petersen graph P (m,a) are both O( m 2a ),where a ≥ 3. 相似文献
956.
In this paper it is proved that for a Lawson compact algebraic dcpo D and a bifinite domain L with smallest element, the function space [D→L] is algebraic and Lawson compact. 相似文献
957.
Let (v,u×c,λ)-splitting BIBD denote a (v,u×c,λ)-splitting balanced incomplete block design of order v with block size u×c and index λ. Necessary conditions for the existence of a (v,u×c,λ)-splitting BIBD are v≥uc, λ(v−1)≡0 (mod c(u−1)) and λ
v(v−1)≡0 (mod (c
2
u(u−1))). We show in this paper that the necessary conditions for the existence of a (v,3×3,λ)-splitting BIBD are also sufficient with possible exceptions when (1) (v,λ)∈{(55,1),(39,9k):k=1,2,…}, (2) λ≡0 (mod 54) and v≡0 (mod 2). We also show that there exists a (v,3×4,1)-splitting BIBD when v≡1 (mod 96). As its application, we obtain a new infinite class of optimal 4-splitting authentication codes. 相似文献
958.
荧光染料掺杂的高效率、高亮度白色有机电致发光器件 总被引:1,自引:0,他引:1
制备了结构为 ITO/NPB(30 nm)/Rubrene(0.2 nm)/CBP:Bczvbi(8 nm,x%)/Bphen(30 nm)/Cs2CO3:Ag2O(2 nm,20%)/Al(100 nm)的器件。研究了Bczvbi掺杂浓度(x=5,10,15)对白光器件性能的影响。综合利用发光层中主客体之间的能量转移和空穴阻挡层的空穴阻挡特性,得到了高效率、高亮度的白色有机电致发光器件。当Bczvbi的掺杂质量分数为10%时,器件的效率和亮度都为最大。驱动电压为7 V时,最大电流效率为4.61 cd/A;驱动电压为9 V时,最大亮度为21 240 cd/m2。当驱动电压从4 V增加到9 V时,色坐标从(0.36,0.38)变化为(0.27,0.29),均处于白光区域。 相似文献
959.
960.
本文采用直流磁控溅射法在三种不同的下电极(BEs)上制备了ZnO薄膜, 获得了W/ZnO/BEs存储器结构. 研究了不同的下电极材料对器件电阻开关特性的影响. 研究结果表明, 以不同下电极所制备的器件都具有单极性电阻开关特性. 在低阻态时, ZnO薄膜的导电机理为欧姆传导, 而高阻态时薄膜的导电机理为空间电荷限制电流. 不同下电极与ZnO薄膜之间的肖特基势垒高度对电阻开关过程中的操作电压有较大的影响, 并基于导电细丝模型对不同下电极上ZnO薄膜的低阻态阻值及reset电流的变化进行了解释.
关键词:
ZnO薄膜
电阻开关
下电极 相似文献