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1.
Two new sterols have been isolated from the aquatic plant Ruppia maritima and their structures were established as (24R) ergosta-8,22-diene-3 beta,6 beta,7 alpha-triol (1) and (24R) ergosta-8(14),22-diene-3 beta,6 beta,7 alpha-triol (2) on the basis of spectroscopic analysis. 相似文献
2.
Prisco Prete Antonino Fiorentino Luigi Rizzo Antonio Proto Raffaele Cucciniello 《Current Opinion in Green and Sustainable Chemistry》2021
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3.
Schmidt EG Arkin CR Fiorentino MA Laude DA 《Journal of the American Society for Mass Spectrometry》2000,11(11):1009-1015
Simultaneous excitation/detection (SED), which permits observation of ion motion during an excitation event, is used to generate real-time Fourier transform ion cyclotron resonance (FTICR) excitation profiles that track the radial extent of ion motion in a trapped-ion cell. The conventional FTICR excitation profile is collected in a series of individual experiments in which peak magnitude is monitored as excitation voltage is increased. In contrast, SED permits the single-scan detection of ion cyclotron motion within the trapped-ion cell and consequently yields the data that produces a real-time excitation profile. Data analysis techniques are presented that facilitate conversion of a time domain SED profile into an excitation profile. An order of magnitude decrease in the amount of time is required to acquire an excitation profile, while the precision of the measurement is improved. To demonstrate the utility of the technique, it is applied to the study of axial and radial ion loss mechanisms for argon, benzene, and acetophenone ions under different conditions. SED excitation profiles are also used to illustrate the facility of quadrupolar excitation for minimizing radial ion loss. 相似文献
4.
Soliton squeezing in microstructure fiber 总被引:4,自引:0,他引:4
We demonstrate, for the first time to our knowledge, the generation of squeezed light by means of soliton self-phase modulation in microstructure fiber. We observe and characterize the formation of solitons in the microstructure fiber at 1550 nm. A maximum squeezing of 2.7 dB is observed, corresponding to 4.0 dB after correcting for detection losses. The dependence of this quantum-noise reduction on various system parameters is studied in detail. Features of the microstructure fiber can be exploited for generation of low-energy continuous-variable entangled pulses for use in all-fiber teleportation experiments. 相似文献
5.
We demonstrate a robust implementation of a deterministic linear-optical controlled-not gate for single-photon two-qubit quantum logic. A polarization Sagnac interferometer with an embedded 45 degrees -oriented dove prism is used to enable the polarization control qubit to act on the momentum (spatial) target qubit of the same photon. The optical controlled-not gate requires no active stabilization because the two spatial modes share a common path, and it is used to entangle the polarization and momentum qubits. 相似文献
6.
Assunta Esposito Pietro Filippo De Luca Vittoria Graziani Brigida DAbrosca Antonio Fiorentino Monica Scognamiglio 《Molecules (Basel, Switzerland)》2021,26(13)
Olea europaea germplasm is constituted by a huge number of cultivars, each one characterized by specific features. In this context, endemic cultivars evolved for a very long period in a precise local area, developing very specific traits. These characteristics include the production and accumulation of phytochemicals, many of which are also responsible for the nutraceutical value of the drupes and of the oils therefrom. With the aim of obtaining information on the phytochemical profile of drupes of autochthonous cultivars of Cilento, Vallo di Diano and Alburni National Park, a metabolomics-based study was carried out on 19 selected cultivars. Multivariate data analysis of 1H-NMR data and 2D NMR analyses allowed the rapid identification of metabolites that were qualitatively and/or quantitatively varying among the cultivars. This study allowed to identify the cultivars Racioppella, Guglia, Pizzulella, Oliva amara, and Racioppa as the richest in health-promoting phenolic compounds. Furthermore, it showed a significant variability among the different cultivars, suggesting the possibility of using metabolic fingerprinting approaches for cultivar differentiation, once that further studies aimed at assessing the influence of growing conditions and environmental factors on the chemical profiles of single cultivars are carried out. 相似文献
7.
M. Bernardini D. Bollini P.L. Brunini E. Fiorentino T. Massam L. Monari F. Palmonari F. Rimondi A. Zichichi 《Physics letters. [Part B]》1973,45(2):169-170
Further proof is given for the inadequacy of the peaking approximation in first-order radiative corrections, via the observation of 429 non-coplanar (e+e?) events. The energy dependence of this effects is measured in the s-range 1.44 to 9.0 GeV2, and represents another proof of the validity of QED. 相似文献
8.
V. Alles-Borelli M. Bernardini D. Bollini P.L. Brunini E. Fiorentino T. Massam L. Monari F. Palmonari F. Rimondi A. Zichichi 《Physics letters. [Part B]》1972
The proof is given for the existence of the reaction e+e− → h±h? in the energy range 1400–2400 MeV, and its energy dependence is compared with that of e+e− → e±e?, in the same experimental conditions of observation. The exponent of the s-dependence of the ratio α = (e+e− → h±h?)/ (e+e− → e±e?) is measured to be n = 2.08 ± 0.45, in the s-range (1.96 − 5.76) GeV2, on the basis of 51 e+e− → h±h? events and 8918 e+e− → e±e? events observed. 相似文献
9.
D'Abrosca B Dellagreca M Fiorentino A Golino A Monaco P Zarrelli A 《Natural product research》2006,20(3):293-298
Three new compounds, a sesquilignans, an oxyneolignan and a norlignan, have been isolated from the aqueous fraction of Cestrum parqui. All of the compounds have been identified on the basis of their spectroscopic properties and tested on the species Lactuca sativa and Lycopersicon esculentum to evaluate their phytotoxic activity. 相似文献
10.