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91.
S. Hiltunen 《Monatshefte für Mathematik》2000,129(2):109-117
We prove a Frobenius theorem for Banach space complemented subbundles of the tangent bundle of a manifold modelled on locally
convex spaces. The proof is based on an implicit function theorem for maps from locally convex spaces to Banach spaces proved
in a recent paper of the author.
(Received 15 March 1999; in revised form 2 June 1999) 相似文献
92.
Capillary SFC was applied to the analysis of Some plant volatile oils. The results were compared with those obtained by capillary GC. For thyme oil, SFC without derivatization gave about the same percentage composition of the main compounds as CGC with silylation, thus eliminating one working step. For a complex mixture of peppermint oil or basil oil, SFC seems to give more reliable quantification than CGC, especially for oxygenated compounds. However, the separation efficiency of CGC for monoterpene hydrocarbons was, as expected, much better than that of SFC. 相似文献
93.
94.
Antson H. Grasserbauer M. Hamilo M. Hiltunen L. Koskinen T. Leskelä M. Niinistö L. Stingeder G. Tammenmaa M. 《Analytical and bioanalytical chemistry》1985,322(2):175-180
Analytical and Bioanalytical Chemistry - The recently developed Atomic Layer Epitaxy (ALE) method produces good quality electroluminescent thin-film structures which can be used in various display... 相似文献
95.
Dr. Maning Liu Hannu Pasanen Dr. Harri Ali-Löytty Dr. Arto Hiltunen Dr. Kimmo Lahtonen Syeda Qudsia Dr. Jan-Henrik Smått Prof. Mika Valden Prof. Nikolai V. Tkachenko Assoc. Prof. Paola Vivo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22301-22309
Colloidal lead-free perovskite nanocrystals have recently received extensive attention because of their facile synthesis, the outstanding size-tunable optoelectronic properties, and less or no toxicity in their commercial applications. Tin (Sn) has so far led to the most efficient lead-free solar cells, yet showing highly unstable characteristics in ambient conditions. Here, we propose the synthesis of all-inorganic mixture Sn-Ge perovskite nanocrystals, demonstrating the role of Ge2+ in stabilizing Sn2+ cation while enhancing the optical and photophysical properties. The partial replacement of Sn atoms by Ge atoms in the nanostructures effectively fills the high density of Sn vacancies, reducing the surface traps and leading to a longer excitonic lifetime and increased photoluminescence quantum yield. The resultant Sn-Ge nanocrystals-based devices show the highest efficiency of 4.9 %, enhanced by nearly 60 % compared to that of pure Sn nanocrystals-based devices. 相似文献
96.
Zhuo-Lin Wang Kari Hiltunen Petri Orava Jukka Seppälä Yu-Yen Linko 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):599-612
Abstract The use of lipase as biocatalyst in polyesterification of aliphatic diacids or their derivatives, and diols in an organic solvent has been discussed. We have demonstrated that bis(2-chloroethyl) esters of succinic, fumaric, and maleic acid, and bis(2,2,2-trifluoroethyl) sebacate and -dodecanedioate can be polymerized by lipase-catalyzed polytransesterification. Maleate was isomerized to fumarate even under mild reaction conditions, resulting in poly(1,4-butyl fumarate). In order to obtain a high mass-average molar mass of the polyester, solid Mucor miehei lipase was found to be the best lipase and diphenyl ether the best solvent of several investigated. There was no clear relationship with the log P value of the solvent and the polyesterification activity of lipase. The highest degree of polymerization (DP = 184) of poly(1,4-butyl sebacate) with a mass-average molar mass of 46,600 g·mol?1 was obtained in polytransesterification of bis(2,2,2-trifluoroethyl) sebacate and 1,4-butanediol using a programmed vacuum profile. However, a mass-average molar mass as high as about 42,000 g·mol?1 (DP = 167) was also obtained with free sebacic acid when vacuum was employed to remove the water formed during esterification. The mass average molar mass of the polyester increased with an increase in the relative quantity of lipase up to 1 g per 1.5 mmol of diacid, with an increase in the molar mass of the aliphatic diol up to 1,5-pentanediol, and with an increase in the concentration of substrates up to 0.83 M. 相似文献
97.
Spartina alterniflora plants were collected at the Rockefeller Wildlife Refuge near Lake Charles, Louisiana for phytoremediation (phytoextraction) studies. In order to determine whether the plant would thrive in different soils and undergo phytoremediation, three soils were used and analyzed: experimental controlled soil (minimum heavy metal contamination), spiked soil (spiked with 100 ppm of selected heavy metals of Cr, Cu, Pb, Fe and Zn) collected from a local store and contaminated soil collected from the known contaminated (with metals) Bayou d'Inde in Lake Charles, Louisiana. The plant grew evenly in each of the three soils. Based on the inductively coupled plasma-optical emission spectrometric determination of the plant in each soil, it was shown that S. alterniflora exhibited potential for phytoremediation of metals in soils via phytoextraction into the roots. 相似文献