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51.
Abstract

In this work, electron transport layers (ETLs) with high charge transfer ability were prepared by doping ZnO nanoparticles with different concentrations of cadmium(Cd). The inverted polymer solar cell based on PTB7-Th: PC71BM as active layer and various concentrations Cd-doped ZnO (CZO) as ETLs were fabricated. The PCE of the device with optimized Cd content in the ZnO film was about 14.7% larger than that of the pure ZnO-based cells. The cadmium-doped ZnO(CZO) is a good candidate to be used as a high-quality transparent electrode in solar cell applications.  相似文献   
52.
The crystal structure of calcium succinate monohydrate, Ca(C4H4O4)·H2O, has been determined by single crystal X-ray diffraction. The crystals are monoclinic witha=11.952(2),b=9.691(2),c=11.606(2)Å, =108.81(1)°, space group C2/c,Z=8,V=1272.49 Å3,d m =1.80, andd c =1.818 Mg m–3. The structure was refined by full-matrix least-squares techniques toR=0.027,R w =0.040, for 829 reflections with13(I). Ca is coordinated to seven oxygen atoms, and the coordination polyhedron is best described as a pentagonal bipyramid. One carboxylate group in the succinate ion is bonded to three different Ca ions, forming a four-membered chelate ring with one Ca ion is bonded to three different Ca ions, forming a four-membered chelate ring with one Ca ion and unidentate bridge bonds to two other Ca ions. The other carboxylate group is bonded to two Ca ions through unidentate bonds. The structure is highly polymeric. The general structural features are nearly identical to those of calcium adipate monohydrate.Certain commercial materials and equipment are identified in this paper to specify the experimental procedure. In no instance does such identification imply recommendation or endorsement by the National Institute of Standards and Technology or the ADA Health Foundation or that the material or equipment identified is necessarily the best available for the purpose.  相似文献   
53.
在具有开放骨架结构的过渡金属磷酸盐微孔材料的合成中,钒磷酸盐因在催化和磁学方面具有潜在的性质和特殊结构特征而引起人们的广泛兴趣.近年来,人们正在尝试用假四面体结构的[HPO3]^2-替代四面体结构的[PO4]^3-,因为{HPO3}结构基元同钒原子的连接方式与{PO4}结构基元和钒原子的连接方式具有明显的差别,  相似文献   
54.
光学渡越辐射作为高能强流电子束束流参数测量的一种方式, 具有时间响应快、分辨率高等特点, 可以测量电子束的束剖面、发散角、能量等多个参数;通过电子束束参数的时间分辨测量则能够了解电子束产生、运输中的问题, 非常有利于加速器的研究与调试. 一种具有时间分辨能力的、利用光学渡越辐射进行高能强流电子束参数测量的系统被建立起来, 并应用到了18.5MeV, 2.5kA, 90ns的实际的电子束束参数的在线测量中, 具有以10ns的时间间隔和3ns的曝光时间来获得90ns内相应的时间分辨的束发射度的变化值的能力, 为加速器的研究提供了又一个强有力的测试手段. 该系统具有的时间分辨能力最高到达10ns, 一次可以拍摄到8幅图像, 最小的曝光时间为3ns, 图像分辨率为1376×1035, 幅面可以达到φ80mm以上.  相似文献   
55.
Based on the concept of multi-resolutions, full search (FS) equivalent fast search methods for vector quantization (VQ) using mean-type pyramid have been developed in previous work.1–4) In this paper, a modified memory-efficient sum pyramid is proposed, which is exact for computing the difference in integer form and features one more new resolution L01 in-between the top 2 levels L0 and L1 of a conventional pyramid. Benefiting from a recursive difference computation at the top 3 levels, the proposed method can reduce the total computational cost obviously. Furthermore, a memory-efficient way of storage for the top 3 levels is integrated to reduce extra memory requirement.  相似文献   
56.
IntroductionDouble_deckreticulatedshellsasamainformoflargespacestructures,arewidelyusedincivilengineeringandmanyotherfields[1,2 ].Oneofthemisthediagonalsquarepyramidreticulatedshallowshell.Theshellconsistsofreversesquarepyramidswhosevertexesarelinkedbylo…  相似文献   
57.
1 INTRODUCTIONInrecentyears,therehasbeenmuchinterestinphosphoranescontainingonlyonephosphorus-phosphorusbondandthestructuresofmostofthesecompoundshavebeenidentifiedbyX-raycrystallography[1~6].In1990,anewtypeofphosphoraneinvolvingtwoP-Pbondswassuccessfullysynthesized[7],butthecrystalstructurewasnotdetermined.Wehavesuccessfullysynthesizedthenovelphosphorane3bear-ingthreeP-Pbonds.Hereitscrystalstructureisreported.2 EXPERIMENTAL2.1 PreparationAllprocedureswereperformedunderN2atmos…  相似文献   
58.
This report summarises the work done during WHEPP-6 (Institute of Mathematical Sciences, Chennai, India, Jan 3–15, 2000) in Working group on ‘B and collider physics’.  相似文献   
59.
This paper describes practical approaches on how to construct bounding pyramids and bounding cones for triangular Bézier surfaces. Examples are provided to illustrate the process of construction and comparison is made between various surface bounding volumes. Furthermore, as a starting point for the construction, we provide a way to compute hodographs of triangular Bézier surfaces and improve the algorithm for computing the bounding cone of a set of vectors.  相似文献   
60.
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