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141.
We investigate short-range correlations in nuclear and hypernuclear matter. Self-energies due to short-range correlations
and their influence on the nucleon and Λ -hyperon spectral functions are described in an approach accounting for a realistic
treatment of mean-field dynamics and a self-consistently derived quasi-particle interaction. Landau-Migdal theory is used
to derived the short-range interaction from a phenomenological Skyrme energy density functional, subtracting the long-range
pionic contributions to the nucleonic spectral functions. We discuss our results for different hyperon-baryon ratios to show
the influence of strangeness on the correlations in hypernuclear matter. 相似文献
142.
143.
144.
L. Chevallier J. Pelkowski 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,104(3):357-376
An exact model is proposed for a gray, isotropically scattering planetary atmosphere in radiative equilibrium. The slab is illuminated on one side by a collimated beam and is bounded on the other side by an emitting and partially reflecting ground. We provide expressions for the incident and reflected fluxes on both boundary surfaces, as well as the temperature of the ground and the temperature distribution in the atmosphere, assuming the latter to be in local thermodynamic equilibrium. Tables and curves of the temperature distribution are included for various values of the optical thickness. Finally, semi-infinite atmospheres illuminated from the outside or by sources at infinity is dealt with. 相似文献
145.
Hierarchical structure in polymer‐based drug delivery systems as probed by calorimetric measurements
Pascale Valot Nathalie Sintes‐Zydowicz Jean‐Marie Nedelec Mohamed Baba 《Journal of Polymer Science.Polymer Physics》2010,48(18):1939-1945
Thermoporosimetry (TPM), a differential scanning calorimetry technique that relies on the shift of transition temperatures caused by the confinement of liquids, was applied to elucidate the complex morphology of drug‐loaded polymeric microcapsules prepared by the emulsion solvent evaporation method. For the very first time, TPM has been applied simultaneously with two liquids as structural probes. It was found that Miglyol, which dissolves the selected drug (Ibuprofen), is confined inside vesicles having a mean radius of 26.3 nm, whereas water, which is the continuous phase, is trapped inside a swollen polymeric network of Eudragit with an average mesh radius of 1.7 nm. A proposed hierarchical structure is given, which predicts that Eudragit microcapsules are formed from a collection of inert oil vesicles partitioned by polymeric Eudragit membranes swollen by water. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1939–1945, 2010 相似文献
146.
W. A. Korfmacher L. G. Rushing J. Arey B. Zielinska J. N. Pitts 《Journal of separation science》1987,10(12):641-646
This paper describes the use of high resolution capillary gas chromatography combined with negative ion atmospheric pressure ionization mass spectrometry (NIAPIMS) for the analysis of an air particulate extract for mononitropyrenes and mononitrofluoranthenes, some of which are powerful bacterial mutagens. The results are compared to those obtained by the electron impact mass spectrometric analysis of the same sample In addition, the NIAPIMS method confirmed the identification of 4-nitropyrene in the ambient air sample. 相似文献
147.
E.B.Manoukian 《理论物理通讯》2013,(12):677-686
The paper represents a rigorous treatment of the underlying quantum theory, not just in words but providing the underlying technical details, as to why matter occupies so large a volume and its intimate connection with the Pauli exclusion principle, as more and more matter is put together, as well as of the contraction or shrinkage of "bosonic matter", upon collapse, for which the Panli exclusion is abolished. From the derived explicit bounds of integrals of powers of the particle number densities, explicit bounds on probabilities of the occurrences of the events just described are extracted. These probabilities lead one to infer the change of the "size" or extension of such matter, upon expansion or contraction, respectively, as their content is increased. 相似文献
148.
149.
Summary We show that an extrinsic semiconductor (n-type), containing a deep level from impurity centres, may produce stochastic self-oscillations in the electron density and
in the electric field, under intense illumination which ionizes the deep traps and heats the electrons. The feedback mechanism
is the dependence of the capture coefficient of the deep centres on the electron temperature and the dependence of the deep
energy level on electron temperature and concentration. The conditions for the occurrence of periodic and stochastic self-oscillations
are explicitly given.
Riassunto Si mostra che in un semiconduttore estrinseco (di tipon), contenente impurezze con un livello profondo, si possono produrre auto-oscillazioni stocastiche nella densità di elettroni in modo da ionizzare le impurezze e riscaldare gli elettroni. Il meccanismo responsabile è la dipendenza della sezione di cattura degli elettroni nel livello profondo della temperatura degli elettroni e la dipendenza dell’energia del livello dalla temperatura degli elettroni e dalla loro densitá. Si danno le esplicite condizioni per l’insorgere di auto-oscillazioni periodiche e stocastiche.
Резюме Мы показываем, что собственный полупроводник (n-типа), содержащий глубокий уровень, связанный с примесными центрами, может производить стохастические автоколебания в электронной плотности и в электрическом поле при интенсивном облучении, которое ионизует глубокие ловушки и нагревает электроны. Этот механизм обратной связи представляет зависимость коэффициента захвата для глубоких центров от электронной температуры и зависимость глубокого энергетического уровня от температуры и концентрации электронов. В явном виде приводятся условия для возникновения периодических и стохастических автоколебаний.相似文献
150.
Summary By means of an experimental technique based on a nonsteady-state method,i.e. on the propagation of thermal waves, we have measured at room temperature for oscillation frequencies between 6 and 30 mHz
the thermal diffusivity, the lateral thermal-loss coefficient and the ?fractional heat loss? in Nb and Ta wires as a function
of hydrogen doping. The appearance of hydride formation and precipitation notably changes the behaviour of these quantities.
From these measurements it was also possible to calculate the propagation velocity and attenuation coefficient of thermal
waves. It was found that the increase of the hydrogen concentration in the solid solution produces a gradual decrease in the
velocity and increase in the attenuation coefficient until the solubility limit is reached. For larger hydrogen concentrations,
the velocity showed a tendency to increase towards the value of the pure metal, while the attenuation coefficient decreased
below the value of the pure metal. These results as a whole appear quite promising for studying the properties of hydrogenated
systems.
This work was supported by the Gruppo Nazionale di Struttura della Materia of the Consiglio Nazionale delle Ricerche and by
the Centro Interuniversitario di Struttura della Materia of the M.P.I., Roma (Italia). 相似文献