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991.
Investigation of the copper concentration on photocurrent collection of CuInSe2 solar cells
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In this study, CuInSe2 (CISe) thin films were prepared from thermally evaporated Cu/In precursors, having various Cu/In atomic ratio, under the same selenization conditions. The precursors were converted into CISe absorber by annealing in a quartz tube furnace in the selenium vapours at substrate temperature of 500 °C. We developed four CISe films with Cu/In atomic ratio of 0.81–1.19, denoted as Cu‐very rich, Cu‐rich, Cu‐poor, and Cu‐very poor CISe thin films respectively. The effects of Cu/In atomic ratio on grain size, surface morphology, micro‐structure and defect formation of the resulting CISe films were examined. It has been found that the photovoltaic properties were strongly related to Cu concentration, as well as carrier transport mechanism. Defects at the surface and in the bulk of CISe thin films were observed using X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy, Raman spectroscopy, energy dispersive X‐ray spectroscopy and scanning electron microscopy. Moreover, XRD revealed that the CISe film surface had a preferred orientation along the (112) plane. The XRD intensity and full width at half maximum of the (112) plane of CISe varied according to the Cu/In atomic ratio. Our experimental results show that the Cu‐rich solar cell achieves conversion efficiency of 4.55% and exhibits an exceptional high short‐circuit current density. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
992.
Abstract The dark conductivity of phosphorus‐doped amorphous‐silicon alloys (a‐Si:H:F) prepared by the RF plasma decomposition of a gaseous mixture of SiF4, H2 and diluted PH3 is extremely high; it exceeds 10 (O‐cm)‐1 with only a small amount of PH3 (~500 ppm) added in the gas phase. These doping characteristics represent a significant improvement over the doping characteristics of a‐Si:H alloys prepared by a glow‐discharge of SiH4. The improvement was found to be due to the fact that P‐doped a‐Si:H:F contains microcrystallites which are embedded in an amorphous network. The percolation process in these two‐phase systems gives rise to high conductivity. We have used transmission electron microscopy (TEM) and diffraction (TED) to determine the critical surface fraction, ρc, of crystallinity at the onset of extended conduction. The measured ρc is approximately 0.46. This percolation limit provides a basis for the analysis of the electrical properties of P‐doped a‐Si:H:F. 相似文献
993.
付学 《计算机光盘软件与应用》2012,(4):193-194
计算机节能是节能减排的一项举措,通过编制程序来获取目的计算机的活动性,有效的掌握计算机开机情况。 相似文献
994.
Shih‐Fu Ling 《中国工程学刊》2013,36(2):97-103
Abstract A Galerkin based finite element method is used to solve acoustic pressure distribution in unlined or lined ducts of arbitrary profile with circular cross section. For isoparametric elements with cubic polynomials as shape functions, two elements per wavelength is proved necessary to keep solution error within 2.5%. Several examples are solved to show the capability of the derived technique, and the results, are good. 相似文献
995.
Internet of Things has received much attention over the past de-cade.With the rapid increase in the use of smart devices,we arenow able to collect big data on a daily basis.The data we are gather-ing and related problems are becoming more complex and uncer-tain.Researchers have therefore turned to AI as an efficient way ofdealing with the problems created by big data.This special issue of ZTE 相似文献
996.
单点系泊产品是海洋石油开发工程中的关键设备,介绍了作为其主结构的软管平台制作工艺方法,以及为保证产品的质量要求采取的方案及措施。 相似文献
997.
Thomas G. Kannampallil Kevin Waicekauskas Daniel G. Morrow Kathryn M. Kopren Wai-Tat Fu 《Cognition, Technology & Work》2013,15(2):121-131
Medication adherence—taking medication as prescribed—is critical for successful self-care, especially among older adults. Adherence depends on developing and implementing plans for taking medications. Age-related cognitive declines that affect adherence may be mitigated using external tools that support patient-provider collaboration needed to develop these adherence plans. We tested the effectiveness of structured collaborative medication tools to support better medication planning and adherence practices. Evidence for benefits of collaborative tools has been mixed in terms of their usefulness for medication-scheduling tasks, perhaps because the tools have not been explicitly designed to support patient-provider collaboration. A total of 144 community-dwelling older adults participated in pairs and performed the role of a patient or provider in a simulated patient-provider medication-scheduling task. Each pair worked with a structured (MedTable? and e-MedTable) or unstructured (Medcard) scheduling tool and completed four problems (2 simple and 2 complex). Performance was measured using the following: problem-solving (medication schedule) accuracy, problem-solving time, solution (schedule) optimality, tool usability, collaborative effectiveness, and subjective workload involved in creating the medication schedules. Participants using structured tools produced more accurate and optimal schedules. They also rated subjective workload as lower and thought that the structured tools were easier to use, reduced subjective workload associated with creating the schedules. There was also suggestive evidence that participants using the structured tools rated more highly the quality of their collaboration. Structured medication-scheduling tools have the potential to improve medication adherence among older adults because they support collaborative planning and reduce the cognitive load involved in creating these adherence plans. 相似文献
998.
Abstract
In this study, an easily synthesized polydentate ligand N,N,N’,N’-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine (1) in combination with [Pd(C3H5)Cl]2 was found to be an active catalyst in copper-free Sonogashira reactions. Most substrates, including steric hindered phenyl bromides and heteroaryl bromides, could couple efficiently with terminal alkynes in the presence of low catalyst loading (0.1 mol%) and this catalytic system showed excellent functional group tolerance. The influence of water in this system was also preliminarily investigated via 31P NMR in situ; that is, appropriate water favors the reaction while excess hindered this reaction. 相似文献999.
Ye Fei Fu Wenxi Yuan Xingyu Xiang Yunlong 《Soil Mechanics and Foundation Engineering》2019,56(1):12-20
Soil Mechanics and Foundation Engineering - The softening and degradation effects of water on soil mass, increase of pore water pressure, and reduction of matric suction are usually considered for... 相似文献
1000.
Fu Haiyan Jin Yunlong Ou Hui Huang Ping Liu Chen Luo Yongping Xiao Zonghu 《Journal of Materials Science: Materials in Electronics》2021,32(16):21178-21187
Journal of Materials Science: Materials in Electronics - The highly transparent and conductive poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS)/Ag nanowires (NWs) composite... 相似文献