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排序方式: 共有78条查询结果,搜索用时 5 毫秒
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Bellini G Benziger J Bick D Bonetti S Bonfini G Bravo D Buizza Avanzini M Caccianiga B Cadonati L Calaprice F Carraro C Cavalcante P Chavarria A Chepurnov A D'Angelo D Davini S Derbin A Etenko A Fomenko K Franco D Galbiati C Gazzana S Ghiano C Giammarchi M Goeger-Neff M Goretti A Grandi L Guardincerri E Hardy S Ianni A Ianni A Korablev D Korga G Koshio Y Kryn D Laubenstein M Lewke T Litvinovich E Loer B Lombardi F Lombardi P Ludhova L Machulin I Manecki S Maneschg W Manuzio G Meindl Q Meroni E 《Physical review letters》2012,108(5):051302
We observed, for the first time, solar neutrinos in the 1.0-1.5 MeV energy range. We determined the rate of pep solar neutrino interactions in Borexino to be 3.1±0.6{stat}±0.3{syst} counts/(day·100 ton). Assuming the pep neutrino flux predicted by the standard solar model, we obtained a constraint on the CNO solar neutrino interaction rate of <7.9 counts/(day·100 ton) (95% C.L.). The absence of the solar neutrino signal is disfavored at 99.97% C.L., while the absence of the pep signal is disfavored at 98% C.L. The necessary sensitivity was achieved by adopting data analysis techniques for the rejection of cosmogenic {11}C, the dominant background in the 1-2 MeV region. Assuming the Mikheyev-Smirnov-Wolfenstein large mixing angle solution to solar neutrino oscillations, these values correspond to solar neutrino fluxes of (1.6±0.3)×10{8} cm{-2}?s^{-1} and <7.7×10{8} cm{-2}?s{-1} (95% C.L.), respectively, in agreement with both the high and low metallicity standard solar models. These results represent the first direct evidence of the pep neutrino signal and the strongest constraint of the CNO solar neutrino flux to date. 相似文献
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Terence Davis Matthew C Dix Michal J Rokicki Amy JC Brook Caroline S Widdowson David Kipling Mark C Bagley 《Chemistry Central journal》2011,5(1):1-5
To develop more potent small molecules with enhanced free radical scavenger properties, a series of N-substituted isatin derivatives was synthesized, and the cytoprotective effect on the apoptosis of PC12 cells induced by H2O2 was screened. All these compounds were found to be active, and N-ethyl isatin was found with the most potent activity of 69.7% protective effect on PC12 cells. Structure-activity relationship analyses showed the bioactivity of N-alkyl isatins decline as the increasing of the chain of the alkyl group, furthermore odd-even effect was found in the activity, which is interesting for further investigation. 相似文献
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A. Ianni D. Montanino G. Scioscia 《The European Physical Journal C - Particles and Fields》1999,8(4):609-617
We calculate the event rates induced by high-intensity radioactive sources of (Cr) and of (Sr), to be located near the BOREXINO detector. Calculations are performed both in the standard case and assuming non-standard
properties of neutrinos, including flavor oscillations, neutrino electromagnetic interactions, and deviations from the standard
vector and axial couplings in the -e interaction. It is shown that, in some cases, the current limits on non-standard neutrino properties can be significantly
improved.
Received: 11 January 1999 / Published online: 22 March 1999 相似文献
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The relative rates of H-transfer between partners in ion-neutral complexes were compared with those in intramolecular rearrangements using results of first differential photoionization mass spectrometry measurements. Complex-mediated H-transfers are inferred to have rates of the same order as those for intramolecular hydrogen rearrangements, suggesting a similar range of motion of the reactive sites in both types of reactions. It is also concluded that at their fastest H-transfers take place between the partners in ion-neutral complexes within at most the time of several rotations of the partners in the complexes. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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Nicola Pinna Federica Ianni Francesca Blasi Arianna Stefani Michela Codini Stefano Sabatini Aurlie Schoubben Lina Cossignani 《Molecules (Basel, Switzerland)》2022,27(23)
Pumpkin is considered a functional food with beneficial effects on human health due to the presence of interesting bioactives. In this research, the impact of unconventional ultrasound-assisted extraction (UAE) and microwave-assisted extraction techniques on the recovery of total non-polar carotenoids from Cucurbita moschata pulp was investigated. A binary (hexane:isopropanol, 60:40 v/v) and a ternary (hexane:acetone:ethanol, 50:25:25 v/v/v) mixture were tested. The extracts were characterized for their antioxidant properties by in vitro assays, while the carotenoid profiling was determined by high-performance liquid chromatography coupled with a diode array detector. UAE with the binary mixture (30 min, 45 °C) was the most successful extracting technique, taking into consideration all analytical data and their correlations. In parallel, solid lipid nanoparticles (SLN) were optimized for the encapsulation of the extract, using β-carotene as a reference compound. SLN, loaded with up to 1% β-carotene, had dimensions (~350 nm) compatible with increased intestinal absorption. Additionally, the ABTS ((2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay showed that the technological process did not change the antioxidant capacity of β-carotene. These SLN will be used to load an even higher percentage of the extract without affecting their dimensions due to its liquid nature and higher miscibility with the lipid with respect to the solid β-carotene. 相似文献
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Hannu?TiitinenEmail author Anna?Mari?M?kel? Ville?M?kinen Patrick?JC?May Paavo?Alku 《BMC neuroscience》2005,6(1):62