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81.
Quaternary blended organic solar cells utilize four blended material components(one donor plus three acceptors, two donors and two acceptors, or three donors plus one acceptor) as the active layer materials. The use of four material components allows us to have more material selections and more mechanism choices to improve the photon-to-electron conversion efficiency. In this contribution, we present a new case of quaternary material system, that shows 17.1% efficiency obtained by adding IDIC and PC_(71)BM as the guest acceptors of the host binary of PM6:Y6. The lowest unoccupied molecular orbital(LUMO) levels of IDIC and PC_(71)BM are both higher than that of Y6, which is one reason to obtain increased open-circuit voltage(V_(oc)) in the quaternary device. Upon introduction of IDIC and PC_(71)BM as the acceptor guests, the hole and electron mobilities are both increased, which contributes to the increased short-circuit current-density(J_(sc)). Effects of the weight ratios of the three acceptor components are investigated, which demonstrates that the increased hole and electron mobilities, the accelerated hole-transfer, and the reduced monomolecular recombination are the factors contributing to the increased J_(sc)and fill-factor. This case of quaternary device demonstrates the applicability of the quaternary strategy in increasing the device functions and hence the efficiencies in the field of organic photovoltaic cells. 相似文献
82.
选用2-(N,N-双(二苯基膦基甲基))胺基吡啶(bdppmapy)为膦配体、二吡啶并[3,2-a∶2'',3''-c]吩嗪(dppz)为氮配体、[Cu (CH3CN)4]BF4为铜盐,在常温下进行反应,制备了3种新型Cu(Ⅰ)配合物,分别为[Cu (dppz)(bdppmapy)]2(BF4)2·H2O (CuBF4-1)、[Cu (dppz)(bdppmapy)]BF4(CuBF4-2)和[Cu (dppz)(bdppmapy)]BF4(CuBF4-3)。获得了CuBF4-1和CuBF4-3的单晶,发现了单晶到单晶转化过程的现象,并探究了溶剂分子的存在对配合物结构和光物理性能的影响。通过单晶X射线衍射确定配合物CuBF4-1和CuBF4-3的结构,使用粉末X射线衍射(PXRD)、红外光谱(IR)和核磁共振氢谱/磷谱(1H/31P NMR)对合成的3个配合物进行结构表征。对配合物进行紫外可见吸收光谱(UV-Vis)、荧光光谱、荧光寿命及量子产率等光物理性质的表征和分析,比较了配合物发光性质的差异,探讨了溶剂分子对配合物结构和光物理性质的影响规律。太赫兹时域光谱对配合物的研究提供了帮助。 相似文献
83.
84.
This paper obtains an entangled condition for isotropic-like states by using an atomic map. It constructs a class of bound entangled states from the entangled condition and shows that the partial transposition of the state from the constructed bound entangled class is an edge bound entangled state by using range criterion. 相似文献
85.
L-Fuzzy拓扑空间中一种新型的强F仿紧性 总被引:8,自引:1,他引:8
本文引入一种新型的强F仿紧性─—Ⅲ型强F仿紧性,它是基于α-局部有限族概念提出的,这种α-局部有限族概念可用于刻划强F可数紧性。 相似文献
86.
This paper shows that by choosing suitably the general fundamental invariantI=f(I1) as a new canonical momentum, we can find the semiclassical propagator for any one-dimensional admissible potential, whereIis a certain function of the fundamental invariantI1. We apply this method to the case of quartic potential and point out few applications of the propagator for this potential. 相似文献
87.
88.
New classes of domains with explicit Bergman kernel 总被引:9,自引:1,他引:8
Roos GUY 《中国科学A辑(英文版)》2004,47(3):352-371
We introduce two classes of egg type domains, built on general bounded sym-metric domains, for which we obtain the Bergman kernel in explicit formulas. As an aux-iliary tool, we compute the integral of complex powers of the generic norm on a boundedsymmetric domains using the well-known integral of Selberg. This generalizes matrix in-tegrals of Hua and leads to a special polynomial with integer or half-integer coefficientsattached to each irreducible bounded symmetric domain. 相似文献
89.
In this paper, we classify the regular embeddings of arc-transitive simple graphs of order pq for any two primes p and q (not necessarily distinct) into orientable surfaces. Our classification is obtained by direct analysis of the structure of arc-regular subgroups (with cyclic vertex-stabilizers) of the automorphism groups of such graphs. This work is independent of the classification of primitive permutation groups of degree p or degree pq for p q and it is also independent of the classification of the arc-transitive graphs of order pq for p q. 相似文献
90.
FangWANG ShiHongCHENG 《数学学报(英文版)》2004,20(5):869-878
We obtain an almost sure central limit theorem (ASCLT) for heavily trimmed sums. We also prove a function-typed ASCLT under the same conditions that assure measurable functions to satisfy the ASCLT for the partial sums of i.i.d, random variables with E X1 = 0, EX1^2 = 1. 相似文献