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551.
Polycrystalline samples of α-Zr(HPO4)2·H2O with different relative densities were investigated by ac admittance measurements at 20°C and 75% relative humidity. The analysis of the frequency response allowed an equivalent circuit to be derived whose parameters were calculated by complex non-linear regression. It was found that the response of the polycrystalline samples was accurately modelled by a parallel combination of a resistance and a constant phase-angle element, both strongly dependent on relative density. The results are discussed on the basis of the present knowledge of the electrical properties of α-Zr(HPO4)2·H2O. 相似文献
552.
M.P. Fontana P.P. Lottici C. Razzetti D. Bianchi G. Antonioli U. Emiliani 《Solid State Communications》1982,43(7):561-565
EXAFS measurements at different temperatures on amorphous arsenic are reported. The low values of the EXAFS mean square relative displacement σ2 for the first coordination shell are consistent with a distribution of As4 pyramidal units throughout the amorphous network, giving a locally very ordered first shell, whose disorder is essentially dynamic in character. The temperature dependence of the vibrational contribution to the EXAFS Debye-Waller factor is well described by an Einstein oscillator model. 相似文献
553.
Umberto Bianchi Carla Cuniberti Enrico Pedemonte Corrado Rossi 《Journal of Polymer Science.Polymer Physics》1969,7(5):845-853
The conformational energy contribution (ΔUconf) to the heat of solution in polymer-solvent systems is presented and discussed in connection with chain conformational properties. In particular, ΔUconf has been discussed in terms of various possible mechanisms of coil deformation. 相似文献
554.
Electrical conductivities of dilute sodium hydroxide aqueous solutions have been determined at 75, 100 and 150°C at 1.6 MPa using a recently developed DC-measuring technique especially suited for the study of aqueous solutions above room temperature. The data were analyzed with modern theories to obtain the infinite dilution conductivity and the association constant at the three temperatures. 相似文献
555.
A Raffaelli S Pucci I Desideri C R Bellina R Bianchi P Salvadori 《Journal of chromatography. A》1999,854(1-2):57-67
Radioactive iodine (131I and 123I) labelled methylene blue is used for the early diagnosis of melanoma metastases. We studied the iodination reaction of methylene blue (using "cold" iodine) in order to characterise the iodination product(s) as far as number and position of iodine atoms introduced on the aromatic ring(s) is concerned. The reaction was carried out under the same experimental conditions used for the radioactive one, that is in a large excess of methylene blue. The ionspray HPLC-MS analysis of the reaction mixture showed that the iodinated methylene blue was present only in a very small amount and the main iodinated product was a demethylated one, coming out from the iodination of an impurity azure B. We also studied the iodination reaction of azure B in order to better explain the reaction pathway. Commercial azure B contains impurities of methylene blue and all the possible demethylated derivatives. HPLC-MS analysis of the reaction mixture allowed a complete characterisation of the iodinated and bis-iodinated products. 相似文献
556.
Bianchi Lavinia Kirwan Kerry Alibardi Luca Pidou Marc Coles Stuart R. 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1303-1314
Journal of Thermal Analysis and Calorimetry - Chemical precipitation is a consolidated technique applied in wastewater treatment to remove and recover phosphorous and ammonium that remain in the... 相似文献
557.
Bianchi L Maccagno M Petrillo G Sancassan F Tavani C Morganti S Rizzato E Spinelli D 《The Journal of organic chemistry》2007,72(15):5771-5777
4-Alkyl-2-nitrothiophenes [10: R = CH3, CH(OH)CH3, CH(OCH3)CH3] react with secondary aliphatic amines, in the presence of AgNO3, to give 3-alkyl-2-amino-5-nitrothiophenes (12) through an oxidative nucleophilic substitution of hydrogen (ONSH) of synthetic interest. This behavior is in striking contrast with that of the parent 2-nitrothiophene (6), which was found to undergo ring-opening in analogous reaction conditions. A possible rationale for the crucial effect of alkyl groups is suggested, grounded also on a study of the corresponding Meisenheimer-like adducts. 相似文献
558.
A generalized Bloch sphere, in which the states of a quantum entity of arbitrary dimension are geometrically represented, is investigated and further extended, to also incorporate the measurements. This extended representation constitutes a general solution to the measurement problem, inasmuch it allows to derive the Born rule as an average over hidden-variables, describing not the state of the quantum entity, but its interaction with the measuring system. According to this modelization, a quantum measurement is to be understood, in general, as a tripartite process, formed by an initial deterministic decoherence-like process, a subsequent indeterministic collapse-like process, and a final deterministic purification-like process. We also show that quantum probabilities can be generally interpreted as the probabilities of a first-order non-classical theory, describing situations of maximal lack of knowledge regarding the process of actualization of potential interactions, during a measurement. 相似文献
559.
Eugenio Bianchi 《General Relativity and Gravitation》2014,46(2):1-23
In this paper we calculate the Bondi mass of asymptotically flat spacetimes with interacting electromagnetic and scalar fields. The system of coupled Einstein–Maxwell–Klein–Gordon equations is investigated and corresponding field equations are written in the spinor form and in the Newman–Penrose formalism. Asymptotically flat solution of the resulting system is found near null infinity. Finally we use the asymptotic twistor equation to find the Bondi mass of the spacetime and derive the Bondi mass-loss formula. We compare the results with our previous work (Bi?ák et al. in Class Quantum Gravity 27(17):175011, 2010) and show that, unlike the conformal scalar field, the (Maxwell–)Klein–Gordon field has negatively semi-definite mass-loss formula. 相似文献
560.