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81.
82.
We demonstrate the possibility to perform very high-sensitivity spectroscopy of CO2 around 4.25 μm wavelength, by use of a difference-frequency radiation source and a White-type multipass absorption cell. Several methods for fringing noise reduction were successfully adopted. In particular, a novel technique to reduce fringes by choosing proper values of the frequency modulation amplitude is described in detail. Pressure-broadening measurements of high-J rovibrational transitions are presented. Achievable laboratory and field sensitivity limits are discussed. 相似文献
83.
A.A. Natale 《Nuclear Physics B》1983,226(2):365-386
Dynamical symmetry breaking in non-abelian gauge theories is studied by computing an effective potential for composite operators. We obtain consistent solutions of chiral and gauge symmetry breaking which are, in some cases, compatible with a short distance behavior. The effective theory determined is in agreement with the tumbling hypothesis. 相似文献
84.
85.
P.?Cancio S.?Bartalini S.?Borri I.?Galli G.?Gagliardi G.?Giusfredi P.?Maddaloni P.?Malara D.?MazzottiEmail author P.?De?Natale 《Applied physics. B, Lasers and optics》2011,102(2):255-269
We report on recent development of IR spectrometers based on non-linear optical generation and quantum-cascade lasers. Frequency
stabilization and referencing to optical frequency-comb synthesizers is described. Their characteristics for spectroscopic
as well as metrological applications are pointed out. The potential of the combination of mid-IR sources with enhancement
cavities for high-resolution and sensitive measurements of gas spectra is illustrated. Finally, we describe wave-front engineering
of long wavelength beams for spatial control and imaging applications. 相似文献
86.
D Cauzzi R Pattacini M Delferro F Dini C Di Natale R Paolesse S Bonacchi M Montalti N Zaccheroni M Calvaresi F Zerbetto L Prodi 《Angewandte Chemie (International ed. in English)》2012,51(38):9662-9665
The heat is on: A Cu(5) metal cluster presents distinctive photophysical properties that result in a temperature-dependent fluorescent quantum yield and excited-state lifetime between -45 and +80?°C, both in solution and as a solid. Unprecedented accuracy in temperature determination by fluorescence measurements was achieved with this complex, thus making it suitable for applications in, for example, biology and (nano)materials research. 相似文献
87.
The scalar Higgs boson mass in a Technicolor model was obtained by Elias and Scadron with the analysis of an homogeneous Bethe–Salpeter equation (BSE), however it was performed before the most recent developments of walking gauge theories. It was not observed in their work that dynamically generated technifermion mass may vary according to the theory dynamics that forms the scalar bound state. This will be done in this work and we also call attention that their calculation must change to take into account the normalization condition of the BSE. We compute the width of the composite boson and show how the gauge group and fermion content of a technicolor theory can be inferred from the measurement of the mass and width of the scalar boson. 相似文献
88.
89.
C. Meola G.M. Carlomagno M. Di Foggia O. Natale 《Applied Physics A: Materials Science & Processing》2008,91(4):685-691
A serious problem in the production of gas turbine blades is the detection of residual ceramic cores inside the cooling passages;
in fact, the presence of even small ceramic pieces affects turbine performance and may cause difficulties in successive manufacturing.
Therefore, it is important to have a non-destructive technique that must be capable of detecting tiny ceramic fragments in
a fast and easy way. In this perspective, the suitability of infrared thermography was investigated within cooperation between
the University of Naples and the Europea Microfusioni Aerospaziali S.p.A. (EMA). Several blades of three different types were
inspected revealing that in many cases infrared thermography can discover small ceramic fragments which were missed by X-ray
inspection. In addition, infrared thermography allows gaining of information about other types of anomalies (e.g., surface
defects) during the same testing step (by eventually changing the test parameters) and then saving time and money. The obtained
results look promising in view of introducing infrared thermography among industrial instrumentation as an alternative to,
or integrated with, the most currently utilized non-destructive techniques. 相似文献
90.
Hantzsch conditions with N-benzylamine gave carbocycle 3 rather than a dihydropyridine when isoxazolealdehyde 2 was employed. 相似文献