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1.
G. Carelli N. Ioli A. Messina A. Moretti S. Schepis F. Strumia 《International Journal of Infrared and Millimeter Waves》1998,19(9):1191-1199
We measured the dependence of the reflectivity of InSb crystals upon temperature in the submillimeter region using monochromatic radiation from an optically pumped far infrared (FIR) laser. The measures allowed us to determine the value of the electron effective mass at low temperatures with radiations of different frequencies. Our measurements extend the results obtained recently on pure crystals with magneto-optical methods to the low temperatures region where only old measures were available. 相似文献
2.
A. Di Maio A. Rocco P. Ferraro M. De Rosa P. De Natale S. De Nicola A. Finizio G. Pierattini G. Coppola M. Iodice V. Striano 《Optics and Lasers in Engineering》2007,45(3):385
In view of the growing interest for non-destructive tests of materials, geodynamical monitoring and in general remote sensing, there is a great effort to bring practical optical sensors from research labs to industrial and environmental applications. In this paper, we employ digital holographic technique as an efficient tool for evaluating the strain measurement capability of fiber Bragg gratings (FBG). A cantilever beam has been employed as a test structure under loading test. The strain measurements results obtained by fiber-based sensors have been compared to those obtained by using full-field digital holographic technique and point-wise strain gauge sensors glued on the same cantilever beam. A simple theoretical model is also presented to interpret and compare the experimental results coming from different techniques. 相似文献
3.
J. C. S. Moraes E. M. Telles F. C. Cruz A. Scalabrin D. Pereira C. Garelli N. Ioli A. Moretti F. Strumia 《International Journal of Infrared and Millimeter Waves》1991,12(12):1475-1486
We report the discovery of 57 new fir laser lines from13CD3OH molecule optically pumped by a waveguide CO2 laser of 300 MHz tunability. For all lines, precise frequency offset measurements between the CO2 line center and the center of the absorbing13CD3OH line were performed using the transferred Lamb-Dip technique. We have also measured directly the frequency of seven FIR laser lines by heterodyning with already known laser lines. We present a complete list of all known laser lines (134) and frequency measurements (24) for this molecule.Work supported by CNPq, FAPESP, FAEP-Brasil, and CNR-Italia 相似文献
4.
G. Carelli A. Di Siena N. Ioli A. Moretti G. Moruzzi F. Strumia 《International Journal of Infrared and Millimeter Waves》1994,15(4):619-633
We have measured the frequencies of four CH3OH far-infrared laser lines that were previously known only by wavelength measurement. Two of these lines turned out to be doublets, bringing the total number of measured lines to six. We can now confirm the assignments of five of them and definitely disprove the assignments proposed for the sixth.In particular we confirm the assignments for the four strong laser lines at 205 and 208 µm pumped by the 9-P(34) CO2 laser line. These lines share a common upper level in the first excited CO-stretch state, and terminate in the upper and lower levels of a hybrid state with J=5. Heterodyne frequency measurements and conventional microwave spectroscopy show that both lines are split into two components approximately 3.5 MHz apart. The origin of this further splitting is interpreted as a perturbed K-splitting.Work supported by Consiglio Nazionale delle Ricerche -Italia 相似文献
5.
Rocco Duvenhage 《International Journal of Theoretical Physics》2002,41(1):45-61
We first compare the mathematical structure of quantum and classical mechanics when both are formulated in a C*-algebraic framework. By using finite von Neumann algebras, a quantum mechanical analogue of Liouville's theorem is then proposed. We proceed to study Poincaré recurrence in C*-algebras by mimicking the measure theoretic setting. The results are interpreted as recurrence in quantum mechanics, similar to Poincaré recurrence in classical mechanics. 相似文献
6.
G. Carelli N. Ioli A. Moretti D. Pereira F. Strumia R. Densing 《Applied physics. B, Lasers and optics》1988,45(2):97-100
FIR laser lines close to the N+
3
P
2–3
P
1 transition at 122 m can be used as a local oscillator for heterodyne detectors. The frequencies of some candidate laser lines from CH2F2,13CH3OH, CD3OD, and CD3OH have been measured and the output power of the most interesting lines has been optimized. 相似文献
7.
In an approach to SRS-A and analogues thereof, the key (5, 6)-epoxy alcohol and its 6-epimer were prepared starting from -araboascorbic acid and -diethyl tartrate, respectively. 相似文献
8.
Arrigo Forni Irene Moretti Adele Mucci Fabio Prati Luisa Schenetti 《Chemistry of Heterocyclic Compounds》1995,31(9):1071-1078
A confrgurational and conformational study of NH, N-acetyl- and N-sulfonylaziridine carboxylates is performed by1H ,13C,17O, and15N NMR spectroscopy. The presence of acetyl and su fonyl groups on the ring nitrogen atom seems to reduce greatly the configurational stability at nitrogen.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1226–1234, September, 1995. 相似文献
9.
Arosio D Fontanella M Baldini L Mauri L Bernardi A Casnati A Sansone F Ungaro R 《Journal of the American Chemical Society》2005,127(11):3660-3661
A high-affinity ligand of cholera toxin, the divalent glycocalix[4]arene 1, was obtained by exploiting a combination of structure-based design of glycomimetic monovalent ligands and affinity enhancements by multivalent presentation through a calix[4]arene scaffold. It exhibits a slightly higher affinity for the toxin than its natural ligand, the GM1 oligosaccharide. 相似文献
10.
A. V. Prosyanik A. I. Mishchenko O. V. Zelenskaya A. Forni I. Moretti G. Torre S. Brükner L. Malpezzi V. R. Kostyanovsky R. G. Kostyanovsky 《Russian Chemical Bulletin》1998,47(7):1359-1364
The1H NMR spectra ofO-derivatives of 1-hydroxy-2,2-bis(trifluoromethyl)aziridine containing such substituents as EtO2CCH2, (R/S)-RO2CCH(Me) (R=Me, Pri, or But), (R/S)-H2NC(O)CH(Me), and (R)-H2NC(O)CH(Me) were analyzed. Both of the diastereomerically pure amides of the latter type were isolated. The validity of the1H NMR criteria, which were suggested for the determination of absolute configurations of diastereomers ofN-alkoxyaziridines, was confirmed by X-ray diffraction study of the (R,R)-amide. 相似文献