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Ivona Kafedjiska Igal Levine Artem Musiienko Natalia Maticiuc Tobias Bertram Amran Al-Ashouri Christian A. Kaufmann Steve Albrecht Rutger Schlatmann Iver Lauermann 《Advanced functional materials》2023,33(34):2302924
The performance of five hole-transporting layers (HTLs) is investigated in both single-junction perovskite and Cu(In, Ga)Se2 (CIGSe)-perovskite tandem solar cells: nickel oxide (NiOx,), copper-doped nickel oxide (NiOx:Cu), NiOx+SAM, NiOx:Cu+SAM, and SAM, where SAM is the [2-(3,-6Dimethoxy-9H-carbazol-9yl)ethyl]phosphonic acid (MeO-2PACz) self-assembled monolayer. The performance of the devices is correlated to the charge-carrier dynamics at the HTL/perovskite interface and the limiting factors of these HTLs are analyzed by performing time-resolved and absolute photoluminescence ((Tr)PL), transient surface photovoltage (tr-SPV), and X-ray/UV photoemission spectroscopy (XPS/UPS) measurements on indium tin oxide (ITO)/HTL/perovskite and CIGSe/HTL/perovskite stacks. A high quasi-Fermi level splitting to open-circuit (QFLS-Voc) deficit is detected for the NiOx-based devices, attributed to electron trapping and poor hole extraction at the NiOx-perovskite interface and a low carrier effective lifetime in the bulk of the perovskite. Simultaneously, doping the NiOx with 2% Cu and passivating its surface with MeO-2PACz suppresses the electron trapping, enhances the holes extraction, reduces the non-radiative interfacial recombination, and improves the band alignment. Due to this superior interfacial charge-carrier dynamics, NiOx:Cu+SAM is found to be the most suitable HTL for the monolithic CIGSe-perovskite tandem devices, enabling a power-conversion efficiency (PCE) of 23.4%, Voc of 1.72V, and a fill factor (FF) of 71%, while the remaining four HTLs suffer from prominent Voc and FF losses. 相似文献
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Judit Bar-Ilan 《Scientometrics》2012,92(2):249-260
The impact factor is one of the most used scientometric indicators. Its proper and improper uses have been discussed extensively before. It has been criticized extensively, yet it is still here. In this paper I propose the journal report card, which is a set of measures, each with an easily comprehensible meaning that provides a fuller picture of the journals?? standing. The set of measures in the report card include the impact factor, the h-index, number of citations at different points on the ranked list of citations, extent of uncitedness and coverage of the h-core. The report card is computed for two sets of journals, the top-20 journals in JCR 2010 and the top-20 journals in JCR 2010 for the category Information and Library Science. 相似文献
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The World Wide Web is growing at an enormous speed, and has become an indispensable source for information and research. New
pages are constantly added, but there are additional processes as well: pages are moved or removed and/or their content changes.
We report here the results of an eight year long project started in 1998, when multiple search engines were used to identify
a set of pages containing the term informetrics. Data collection was repeated once a year for the last eight years (with the exception of 2000 and 2001) using both search
engines and revisiting previously identified pages. The results show that the number of pages grew from 866 in 1998 to 28,914
in 2006 — a 33-fold growth. Besides the obvious growth of the topic on the Web, we observed both decay (pages disappearing
from the Web) and modification. Even though most of the pages from 1998 either disappeared or ceased to contain the term informetrics, 165 pages (19.1%) still exist in 2006 and contain the search term. We followed the “fate” of these 165 pages: characterized
the publishers, the contents and the changes that occurred the whole period. In recent years e-print servers and publishers’
sites became sources of large number of pages related to informetrics. Longitudinal studies following the evolution of a topic on the Web are very important, since they provide insights about
content and the underlying Web processes. 相似文献
6.
Igal M. Shohet 《Canadian Metallurgical Quarterly》2006,132(4):345-352
The salient phases in a facility’s service life that are most decisive for the effectiveness of its facilities management (FM) are the preliminary design, construction, and maintenance. The effectiveness of facilities is vastly affected by decisions pertaining to the strategy of the organization that owns or uses the facilities. The goal of this study was to develop key performance indicators (KPIs) for strategic FM that will provide a conclusive approach towards the facility’s service life conditions. Parameters were developed by means of field surveys and statistical analyses, and were validated by means of case studies. The research resulted in a series of 11 KPIs for strategic healthcare FM, which can be classified into four categories: development, organization and management, performance, and maintenance efficiency parameters. The study proposes age and occupancy coefficients as essential parameters for the assessment of large healthcare facilities needs, as an effective measure for long term facility maintenance planning, and for measuring FM effectiveness. The paper stresses that strategic healthcare facilities management must integrate quantitative performance, manpower, and maintenance indicators. 相似文献
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Summary The purpose of this study was to develop a method for characterizing the page and linking patterns related to dramatic events on the Web. As a specific case, we characterized Web pages linking to the set of pages on anthrax indexed by the Yahoo directory (generally acknowledged as a high quality directory). The sample of Web pages was collected shortly after anthrax became a matter of widespread concern (November 2001). The findings show that at that time the “typical' source page was either a news item or a page with a list of links. Most of the examined links were not navigational but linked to the target page in order to provide additional content. Many Web sites added hyperlinks to pages providing presumably authoritative and high quality information on anthrax rather than supplying the information themselves. The results show that Web authors link extensively to presumably “high quality' pages. The methods presented here can be utilized in order to characterize pages and linking patterns of Web pages linking to a set of predefined pages, and the findings of this specific study can serve as a basis for comparison. 相似文献
8.
Changes in chemical constituents during the maturation and ripening of two commercially important pomegranate accessions 总被引:2,自引:0,他引:2
Elinor Shwartz Ira Glazer Irit Bar-Ya’akov Ifat Matityahu Igal Bar-Ilan Doron Holland Rachel Amir 《Food chemistry》2009
Pomegranate juice is well known for its health beneficial compounds. This study was undertaken to investigate changes in the major chemical composition in arils and peels during fruit maturation in two Israeli commercial accessions, ‘Wonderful’ and ‘Rosh-Hapered.’ In both accessions, the levels of total phenolic, antioxidant activity and hydrolysable tannins were reduced in the peels during maturation, while the anthocyanin level increased. The results show that the sugar content in the aril juice increased in both accessions while the levels of acidity and of citric acid decreased. However, these two accessions differed in other parameters in the aril juice, i.e., while the antioxidant and total phenolic contents significantly decreased in ‘Rosh-Hapered’, these changes were not observed in ‘Wonderful’. The anthocyanin level, however, increased in ‘Wonderful’ but did not change in ‘Rosh-Hapered.’ This knowledge could help establish the optimum harvest date ensuring the maximum nutritional properties of pomegranates. 相似文献
9.
Ronen Gottesman Angang Song Igal Levine Maximilian Krause A. T. M. Nazmul Islam Daniel Abou‐Ras Thomas Dittrich Roel van de Krol Abdelkrim Chemseddine 《Advanced functional materials》2020,30(21)
A new method for enhancing the charge separation and photo‐electrochemical stability of CuBi2O4 photoelectrodes by sequentially depositing Bi2O3 and CuO layers on fluorine‐doped tin oxide substrates with pulsed laser deposition (PLD), followed by rapid thermal processing (RTP), resulting in phase‐pure, highly crystalline films after 10 min at 650 °C, is reported. Conventional furnace annealing of similar films for 72 h at 500 °C do not result in phase‐pure CuBi2O4. The combined PLD and RTP approach allow excellent control of the Bi:Cu stoichiometry and results in photoelectrodes with superior electronic properties compared to photoelectrodes fabricated through spray pyrolysis. The low photocurrents of the CuBi2O4 photocathodes fabricated through PLD/RTP in this study are primarily attributed to their low specific surface area, lack of CuO impurities, and limited, slow charge transport in the undoped films. Bare (without protection layers) CuBi2O4 photoelectrodes made with PLD/RTP shows a photocurrent decrease of only 26% after 5 h, which represents the highest stability reported to date for this material. The PLD/RTP fabrication approach offers new possibilities of fabricating complex metal oxides photoelectrodes with a high degree of crystallinity and good electronic properties at higher temperatures than the thermal stability of glass‐based transparent conductive substrates would allow. 相似文献
10.
Scientometrics - Axiomatic characterisation of a bibliometric index provides insight into the properties that the index satisfies and facilitates the comparison of different indices. A geometric... 相似文献