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91.
A Fast Deposition‐Crystallization Procedure for Highly Efficient Lead Iodide Perovskite Thin‐Film Solar Cells 下载免费PDF全文
Manda Xiao Dr. Fuzhi Huang Wenchao Huang Yasmina Dkhissi Dr. Ye Zhu Prof. Dr. Joanne Etheridge Dr. Angus Gray‐Weale Prof. Dr. Udo Bach Prof. Dr. Yi‐Bing Cheng Prof. Dr. Leone Spiccia 《Angewandte Chemie (International ed. in English)》2014,53(37):9898-9903
Thin‐film photovoltaics based on alkylammonium lead iodide perovskite light absorbers have recently emerged as a promising low‐cost solar energy harvesting technology. To date, the perovskite layer in these efficient solar cells has generally been fabricated by either vapor deposition or a two‐step sequential deposition process. We report that flat, uniform thin films of this material can be deposited by a one‐step, solvent‐induced, fast crystallization method involving spin‐coating of a DMF solution of CH3NH3PbI3 followed immediately by exposure to chlorobenzene to induce crystallization. Analysis of the devices and films revealed that the perovskite films consist of large crystalline grains with sizes up to microns. Planar heterojunction solar cells constructed with these solution‐processed thin films yielded an average power conversion efficiency of 13.9±0.7 % and a steady state efficiency of 13 % under standard AM 1.5 conditions. 相似文献
92.
Shorter JH Nelson DD Zahniser MS Parrish ME Crawford DR Gee DL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(5):994-1001
Although nitrogen dioxide (NO(2)) has been previously reported to be present in cigarette smoke, the concentration estimates were derived from kinetic calculations or from measurements of aged smoke, where NO(2) was formed some time after the puff was taken. The objective of this work was to use tunable infrared laser differential absorption spectroscopy (TILDAS) equipped with a quantum cascade (QC) laser to determine if NO(2) could be detected and quantified in a fresh puff of cigarette smoke. A temporal resolution of approximately 0.16s allowed measurements to be taken directly as the NO(2) was formed during the puff. Sidestream cigarette smoke was sampled to determine if NO(2) could be detected using TILDAS. Experiments were conducted using 2R4F Kentucky Reference cigarettes with and without a Cambridge filter pad. NO(2) was detected only in the lighting puff of whole mainstream smoke (without a Cambridge filter pad), with no NO(2) detected in the subsequent puffs. The measurement precision was approximately 1.0 ppbVHz(-1/2), which allows a detection limit of approximately 0.2 ng in a 35 ml puff volume. More NO(2) was generated in the lighting puff using a match or blue flame lighter (29+/-21 ng) than when using an electric lighter (9+/-3 ng). In the presence of a Cambridge filter pad, NO(2) was observed in the gas phase mainstream smoke for every puff (total of 200+/-30 ng/cigarette) and is most likely due to smoke chemistry taking place on the Cambridge filter pad during the smoke collection process. Nitrogen dioxide was observed continuously in the sidestream smoke starting with the lighting puff. 相似文献
93.
Allen SD Almond MJ Bell MG Hollins P Marks S Mortimore JL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(5):959-965
The mineralogy of 11 concretions from the Bronze Age settlement horizons at Brean Down near Weston-super-Mare, Somerset, UK, has been examined by infrared spectroscopy. The concretions are found to contain calcite and apatite and, in some cases, quartz. Four further concretions from the later Iron Age Meare Village, soil samples from Brean Down and mineralised samples of known faecal origin from a cesspit within the Tudor Merchant's house in Tenby have been similarly examined. It is found that all samples contain calcite, but only the concretions and the Tenby cesspit samples contain apatite. None of the soil samples contain apatite, although these are relatively high in quartz. This suggests that the concretions are coprolites and that the apatite has a biological origin in small bone fragments. The infrared study is backed up by scanning electron microscopy which confirms the presence of phosphorus in the coprolite samples and shows a morphology suggestive of the presence of bone fragments; it is likely, therefore, that the coprolites result from a carnivore--most probably from dogs. The findings show the usefulness of infrared spectroscopy for the rapid identification of mineralised coprolitic material from archaeological sites. 相似文献
94.
The enantiomers of (11Z,19Z)-3-acetoxy-11,19-octacosadien-1-ol were synthesized from the enantiomers of 3,4-epoxy-1-butanol PMB ether. Its racemate was also synthesized. Its (S)-isomer and racemate were shown to possess the same pheromone activity as CH503, a long-lived inhibitor of male courtship in Drosophila melanogaster, although the racemate was less active. 相似文献
95.
Singh SB Zink DL Doss GA Polishook JD Ruby C Register E Kelly TM Bonfiglio C Williamson JM Kelly R 《Organic letters》2004,6(3):337-340
[structure: see text] Screening of natural products extracts led to the discovery of citrafungins A and B, two new fungal metabolites of the alkylcitrate family that are inhibitors of GGTase I of various pathogenic fungal species with IC(50) values of 2.5-15 microM. These compounds exhibited antifungal activities with MIC values of 0.40-55 microM. The isolation, structure elucidation, relative and absolute stereochemistry, and biological activities of citrafungins are described. 相似文献
96.
Thorp-Greenwood FL Fernández-Moreira V Millet CO Williams CF Cable J Court JB Hayes AJ Lloyd D Coogan MP 《Chemical communications (Cambridge, England)》2011,47(11):3096-3098
A rhenium polypyridine-based molecular vessel is membrane impermeant when empty, but, upon loading with metal ions, the cationic form is taken up by MCF-7 cells, localising in nucleoli. The luminescence of the vessel and its copper binding ability suggest potential as a bimodal fluorescence/PET imaging agent. 相似文献
97.
A C3-symmetric phosphine with indolyl substituents has been synthesized that demonstrates the capability to bind anions through the indole NH sites and coordinate metal centres through the phosphorus centre. 相似文献
98.
A series of oligoesters based on a rigid triphenyl-diyne core is described. The molecules were readily synthesized from key intermediates, and retained good solubility properties. One of the compounds displayed modest ion transport activity in vesicles, was capable of forming highly conducting single channels in planar bilayers and exhibited an irregular non-linear current-voltage response. All the reported molecules had minimal aqueous fluorescence while being highly fluorescent in less-polar media including lipid vesicles; their partitioning into the membrane could be monitored by a significant blue-shift and increase in fluorescence intensity, as well as a decreased extent of quenching in vesicles over that in water. The combined data indicated that the compounds are highly aggregated in aqueous solution, which limits their membrane partitioning and ion transport activity, in agreement with mechanisms proposed for other 'simple' oligoester channels. 相似文献
99.
Paci P Zvinevich Y Tanimura S Wyslouzil BE Zahniser M Shorter J Nelson D McManus B 《The Journal of chemical physics》2004,121(20):9964-9970
We used a tunable diode laser absorption spectrometer to follow the condensation of D(2)O in a supersonic Laval nozzle. We measured both the concentration of the condensible vapor and the spectroscopic temperature as a function of position and compared the results to those inferred from static pressure measurements. Upstream and in the early stages of condensation, the quantitative agreement between the different experimental techniques is good. Far downstream, the spectroscopic results predict a lower gas phase concentration, a higher condensate mass fraction, and a higher temperature than the pressure measurements. The difference between the two measurement techniques is consistent with a slight compression of the boundary layers along the nozzle walls during condensation. 相似文献
100.
Peter W. Moore Julia K. Schuster Russell J. Hewitt M. Rhia L. Stone Paul H. Teesdale-Spittle Joanne E. Harvey 《Tetrahedron》2014
The ring opening of 1,2-(gem-dibromo)cyclopropyl carbohydrates by two different modes leads to either 2-C-(bromomethylene)pyranosides (using base) or 2-bromooxepines (using silver salts), as shown previously by us for a d-glucal-derived cyclopropane. The base-promoted ring opening is extended to encompass additional alcohol, thiol and amine nucleophiles, and diastereoisomeric cyclopropane precursors. Cross-coupling of the 2-C-(bromomethylene)pyranosides leads to extended 2-C-branched pyranosides. Silver-promoted ring expansion of the cyclopropyl carbohydrates in the presence of various alcohols is described. Cross-coupling of the resulting benzyl 2-bromooxepines affords 2-C-substituted oxepines. 相似文献