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排序方式: 共有118条查询结果,搜索用时 46 毫秒
101.
V. Cuomo P. Di Girolamo R. V. Gagliardi G. Pappalardo N. Spinelli R. Velotta A. Boselli V. Berardi B. Bartoli 《Il Nuovo Cimento C》1995,18(2):209-222
Summary The possibility of performing atmospheric-transmissivity measurements by lidar is considered. In the present paper two distinct
methods have been successfully applied. The first one is based on the detection of the Raman return from molecular nitrogen.
An alternative method is based on the simultaneous detection of the elastic and N2 Raman returns. Measurements based on both techniques are discussed in detail, the second technique producing more accurate
results. Through this technique an estimation of the ?ngstr?m coefficient can also be obtained. 相似文献
102.
V. Cuomo P. Di Girolamo F. Esposito G. Pappalardo C. Serio N. Spinelli M. Armenante B. Bartoli V. Berardi R. Bruzzese C. Bellecci G.E. Caputi F. De Donato P. Gaudio M. Valentini H. Melfi M.P. McCormick 《Applied physics. B, Lasers and optics》1997,64(5):553-559
A,355 and RA,532); the two data sets appearing to be highly correlated. LITE vs. Potenza LIDAR measurements of RA,355 and RA,532 display a correlation coefficient of 0.72 and 0.86, respectively. Stratospheric aerosol dimensional characteristics are determined
starting from the measured values of the ?ngstrom coefficient.
Received: 24 May 1996/Revised version: 8 October 1996 相似文献
103.
Girolamo La Monica Gianattilio Ardizzoia Sergio Cenini Francesca Porta 《Journal of organometallic chemistry》1984,273(2):263-273
The copper(I) azido-derivatives, (PPh3)(phen)CuN3 (Ia) and (PPh3)(TMP)CuN3 (Ib) (phen = 1,10-phenanthroline; TMP = 3,4,7,8-tetramethyl-1,10-phenanthroline), obtained from [(PPh3)2CuN3]2 and the bidentate ligand (biL), react with CS2 to give the thiothiatriazolato-copper(I) complexes, (PPh3)(phen)Cu (IIa) and (PPh3)(TMP)Cu (IIb). The preparation of IIa and IIb occurs only when free triphenylphosphine is present in the reaction medium. The isothiocyanate complexes, (PPh3)(biL)Cu(NCS) (biL = phen, IIIa; biL = TMP, IIIb) are formed, instead of IIa and IIb, when free PPh3 is not added to the reaction medium. The complexes IIIa and IIIb are also obtained when CH2Cl2 solutions of IIa and IIb are stirred for 15 h in the absence of light; if longer reaction times are used, the dimeric isothiocyanato complexes [(biL)Cu(NCS)]2 are formed. Compounds IIa and IIb react with PhCOCl to give (PPh3)(biL)CuCl and 4-benzoyl-1,2,3,4-thiatriazole-5-thione, PhCO.Treatment of Ia and Ib, or [(PPh3)2CuN3]2, with COS did not lead to isolation of characterizable products. An unsaturated molecule such as ethyl propriolate, EtO2CCCH, does not behave as a 1,3-dipolarophile in its reactions with Ia and Ib, the alkynyl derivatives [(biL)Cu2(CCCO2Et)2]n (n is probably 2; biL = phen, IVa; biL = TMP, IVb), being obtained. Similarly the azido-complex [(PPh3)2CuN3]2 reacts with ethyl propiolate to give the asymmetric binuclear alkynyl derivative, (PPh3)3Cu2(CCCO2Et)2 (V). The reaction of V with hydrogen chloride gives EtO2CCCH and the known complex (PPh3)3Cu2Cl2, confirming the above formulation. The reactions of V with neutral ligands such as TMP, phen and CyNC have also been studied, leading to the isolation of new copper(I) alkynyl-derivatives. 相似文献
104.
N. Azaryan J. Budagov J.-Ch. Gayde B. Di Girolamo V. Glagolev M. Lyablin D. Mergelkuhl G. Shirkov 《Physics of Particles and Nuclei Letters》2017,14(1):112-122
In this report a high accuracy method for an interferometric calibration of the Precision Laser Inclinometer (PLI) is proposed. The method is based on the simultaneous measurement of: (a) the PLI base calibration slope (angle), set by a piezoelectric positioner, via laser interferometry and (b) the PLI response signal. A calibration coefficient of 322.5 ± 1.9 μrad/V has been determined experimentally in an interval [4 × 10–7, 4 × 10–6] rad in which there is a linear dependence between the PLI-signal and the calibration angle. 相似文献
105.
Domenico Bruno Fabrizio Greco Paolo Lonetti Paolo Nevone Blasi Girolamo Sgambitterra 《International Journal of Solids and Structures》2010,47(20):2806-2824
An analysis of the effects of microscopic instabilities on the homogenized response of heterogeneous solids with periodic microstructure and incrementally linear constitutive law is here carried out. In order to investigate the possibility to obtain a conservative prediction of microscopic primary instability in terms of homogenized properties, novel macroscopic constitutive stability measures are introduced, corresponding to the positive definiteness of the homogenized moduli tensors relative to a class of conjugate stress–strain pairs.Numerical simulations, addressed to hyperelastic microstructural models representing cellular solids and reinforced composites, are worked out through the implementation of an innovative one-way coupled finite element formulation able to determine sequentially the principal equilibrium solution, the incremental equilibrium solutions providing homogenized moduli and the stability eigenvalue problem solution, for a given monotonic macrostrain path. Both uniaxial and equibiaxial loading conditions are considered.The exact microscopic stability region in the macrostrain space, obtained by taking into account microstructural details, is compared with the macroscopic stability regions determined by means of the introduced macroscopic constitutive measures. These results highlight how the conservativeness of the adopted macroscopic constitutive stability measure with respect to microscopic primary instability, strictly depends on the type of loading condition (tensile or compressive) and the kind of microstructure. 相似文献
106.
Enrico Aiello Gaetano Dattolo Girolamo Cirrincione Anna Maria Almerico Isabella D'Asdia 《Journal of heterocyclic chemistry》1982,19(4):977-979
Monobromo-, monochloro- and monoiodopyrroles are obtained in excellent yields by using N-halosuccinimides in dimethylformamide as halogenating agents. 相似文献
107.
108.
The subject of this paper is the degree of crystallinity and annealing behavior of solution grown single crystals of isotactic polystyrene (IPS) in relation to the fold length, an enquiry which acquires special significance in view of the fact that previously the fold length had been found to be identical over a wide range of crystallization temperatures (Tc). It was found that both crystallinity and thermal stability increase with Tc even over the range of constant fold length thus invalidating the usual assumption that the fold length and crystal properties are uniquely correlated. Further, the crystallinity figures as measured by conventional calorimetry are very low (<50% throughout) which by conventional ideas would require an unrealistically thick amorphous surface layer. However, the “linear crystallinity” (crystal core thickness as determined from x-ray linewidths) is much larger, commensurate with crystallinities in single crystals from other materials. It is suggested that this is the more relevant figure for the subdivision of the lamellas into crystal core and surface layer. The additional amorphous content being otherwise accommodated. Further, this “linear crystallinity” is broadly unaffected by fold length changes induced by heat annealing. The thermal stability (including annealing ability) of the crystals differs markedly whether Tc is above or below ~60°C, a Tc value which is in the range where the fold length is constant, but corresponds to a maximum in the crystallization rate. Possible connections between crystallization conditions and the stability of the resulting crystals (fold length considerations apart) are pointed out. 相似文献
109.
Ken S Di Gennaro G Giulietti G Sebastiano F De Carli D Garreffa G Colonnese C Passariello R Lotterie JA Maraviglia B 《Magnetic resonance imaging》2007,25(6):883-888
Patients with drug-resistant focal epilepsy may require intracranial investigations with subdural electrodes. These must be correctly localized with respect to the brain cortical surface and require appropriate monitoring. For this purpose, coregistration techniques, which fuse preimplantation 3D magnetic resonance imaging scans with postimplantation computed tomography scans, have been implemented. In order to reduce localization errors due to the fusion process, we used a coregistration method based on the maximization of mutual information (MI) in 11 patients with extratemporal epilepsy who were invasively investigated. Our registration method is based on three processing steps: rigid-body transformation for coregistration, computation of MI as a similarity measure and the use of the Downhill Simplex optimization method. After consistency analysis, the shift of the registration method reached 0.14+/-0.27 mm in translation and 0.03+/-0.14 degrees in rotation, and the accuracies assessed on voxels of skull surface and voxels of the center of the brain volume were 1.42+/-0.61 and 1.15+/-0.53 mm, respectively. The accuracy of the fusion process reached submillimeter range, and results were considered reliable for surgical planning in all studied patients. 相似文献
110.
The performance of Cibacron Blue dye (HiTrapBlue or Affigel Blue) in depleting albumin from plasma, as a pre-treatment for biomarker searching in the low-abundance proteome, is here assessed. It is shown that (i) co-depletion of non-albumin species is an ever-present hazard; (ii) the only proper eluant able to release quantitatively the proteins bound to the dye is boiling 4% SDS-25 mM DTT, an ion shock (2 M NaCl) being quite ineffective in releasing the low-abundance species tightly bound to the dye moiety; (iii) the mechanism of dye-protein interaction, after an initial ion-ion docking, is a robust hydrophobic interaction, which progressively augments at lower and lower pH values; (iv) at pH 2.2 in the presence of 0.1% TFA, the blue resin behaves, for all practical purposes, just as a reverse-phase chromatography column, since all residual proteins present in plasma are completely harvested. However Cibacron Blue technology should not necessarily be discarded: As long as also the plasma fraction adsorbed is properly released and analyzed, together with the flow through, one should be able to perform a viable analysis of the low-abundance proteome. 相似文献