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排序方式: 共有276条查询结果,搜索用时 15 毫秒
51.
David Moe Almenningen Brita Susanne Haga Henrik Erring Hansen Dr. Audun Formo Buene Prof. Dr. Bård Helge Hoff Prof. Dr. Odd Reidar Gautun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(51):e202201726
Designing and evaluating novel dye concepts is crucial for the development of the field of dye-sensitized solar cells (DSSCs). In our recent report, the novel concept of tethering the anti-aggregation additive chenodeoxycholic acid (CDCA) to dyes for DSSC was introduced. Based on the performance improvements seen for this modification, the aim of this study is to see if a simplified anti-aggregation unit could achieve similar results. The following study reports the synthesis and photovoltaic characterization of two novel dyes decorated with the steric ethyladamantyl moiety on the π-spacer, and on the triarylamine donor. This modification is demonstrated to be successful in increasing the photovoltages in devices employing copper-based electrolytes compared to the non-modified reference dye. The best photovoltaic performance is achieved by a device prepared with the adamantyl decorated donor dye and CDCA, this device achieves a power conversion efficiency of 6.1 % (Short-circuit current=8.3 mA cm−2, Open-circuit voltage=1054 mV, Fill factor=0.69). The improved photovoltaic performance seen for the adamantyl decorated donor demonstrate the potential of ethyladamantyl side chains as a tool to ensure surface protection of TiO2. 相似文献
52.
53.
I. Alfter E. Bodenstedt B. Hamer J. van den Hoff W. Knichel H. Münning S. Piel R. Sajok J. Schüth 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(3):273-283
Theg-factors of the four lowest states of the ground state rotational band of158Dy have been determined asg(2 1 + )=+0.362(23),g(4 1 su+ )=+0.340(20),g(6 1 su+ )=+0.207(36) andg(8 1 su+ )=+0.21(11). Theg-factors of the 2+ and 4+ states were measured by the IPAC method with radioactive samples of 2.4 h158Er in external magnetic fields. To investigate the higher states, for the first time an on-line γ—γ IPAC experiment was performed with the reaction156Gd(α, 2n)158Dy by use of the static hyperfine field of DyGd. 相似文献
54.
S.A. Dzuba I.V. Borovykh A.J. Hoff 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1998,133(2):286-290
A microwave two-pulse sequence with a weak and long 180° first pulse and a hard 90° second pulse is employed to detect nuclear coherences in pulsed EPR. The coherences created by the first pulse are transferred after an evolution periodTinto an observable FID by the second pulse. The free induction is measured at some fixed delay after the second pulse; it is modulated whenTis varied. As the second pulse may be switched on immediately after the first pulse, the nuclear coherences may be detected immediately as they start to freely oscillate, without loss of information within the instrumental dead time. The method is demonstrated for a sample of the radical cation of15N-labeled bacteriochlorophylla. 相似文献
55.
P. Hoff B. Ekström B. Fogelberg J. P. Omtvedt 《Zeitschrift für Physik A Hadrons and Nuclei》1991,338(3):285-289
The decay properties of84As have been investigated with mass separated sources. Only one β-decaying state is seen, contradictory to previous observations. The halflife is found to be 4.5±0.2 s. A detailed decay scheme has been constructed, and 33 excited states in84Se have been determined. 相似文献
56.
E. Bodenstedt B. Hamer P. Herzog J. van den Hoff H. Münning S. Piel J. Prinz R. Sajok 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(3):249-256
Theg-factor of the 21 + state of192Pt has been measured by the IPAC technique in an external magnetic field as:g(21 +,192Pt)=+0.287(17). An additional IPAC experiment with an192IrFe sample was performed with the same level in order to investigate the hyperfine field. The result:ω L τ(21 +,192PtFe)=0.1115(9) gives the hyperfine field:B hf 4.2k (PtFe)=126.8(71) T. The result of an LTNO experiment with the same level is compatible with the assumption that 100% of the192Ir atoms were on unique sites. 相似文献
57.
A computer programme for determination of equilibrium constant (K) and enantiomer ratio (E) in biocatalytic resolutions has been developed. The programme utilises experimental data, ees and eep measured at more than one conversion, and determines both K and E no matter whether the reaction is irreversible (K=0) or reversible (K>0). An estimation of errors in the calculations indicates that errors in E does not show a Gaussian distribution, while errors in K does. The usefulness of the programme has been tested in a lipase-catalysed transesterification of 1-phenoxy-2-propanol at various concentrations of acyl donor, with different solvents and at different water activities. 相似文献
58.
Site-selection experiments have been performed on pheophytin-a and chlorophyll-a in n-octane at 4.2 K. Single-site absorption spectra of both compounds were recorded, but single-site emission spectra could not be obtained. The absorption spectra show sharp lines and vibrational frequencies of the lowest excited singlet state correspond with resonance Raman frequencies. A remarkable feature of the emission is the presence of a strong 0-0 transition but extremely weak vibronic transitions. 相似文献
59.
Vladimira Jirsakova Françoise Reiss-Husson Bas van Dijk Gabrielle Owen Arnold J. Hoff 《Photochemistry and photobiology》1996,64(2):363-368
The carotenoid triplet states in the light-harvesting complex B800–850from purple bacterium Rubrivivax gelatinosus were characterized by absorption-detected magnetic resonance in zero magnetic field (ADMR) spectroscopy. Detailed HPLC analysis of carotenoids from B800–850demonstrated the presence of several carotenoids bound to the complex: the major ones are hydroxyspheroidene and spheroidene (together 80%), followed by neurosporene and hydroxyneurosporene (7%), spheroidenone and hydroxyspheroidenone (7.5%) and two other minor carotenoids that could be 3,4-dihydrospheroidenone and 3,4-dihydrohydroxyspheroidenone (5.5%). Three triplet states originating from carotenoids present in the B800–850were observed. The identical T-S spectra recorded at selectively chosen 2|E| transitions of carotenoids indicated that all these triplet states can be attributed to three different populations of one carotenoid family, probably to spheroidene and to hydroxyspheroidene, with different out-of-plane distortions of their polyene chain due to a different protein environment. Triplet states of the neurosporene and the spheroidenone families are probably not observed because of the low signal amplitude. 相似文献
60.
E. Bodenstedt B. Gemünden J. van den Hoff S. Piel R. Sajok 《Zeitschrift für Physik A Hadrons and Nuclei》1986,323(3):281-284
TheF-spin formalism is employed to extract scalar boson effective charges from theB(E2, 2 1 + →0g) systematics in rare-earth nuclei. 相似文献