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71.
72.
73.
Tree-connected peer group situations and peer group games 总被引:2,自引:0,他引:2
74.
We investigate the occurrence of waterlike thermodynamic and dynamic anomalous behavior in a one dimensional lattice gas model. The system thermodynamics is obtained using the transfer matrix technique and anomalies on density and thermodynamic response functions are found. When the hydrogen bond (molecules separated by holes) is more attractive than the van der Waals interaction (molecules in contact) a transition between two fluid structures is found at null temperature and high pressure. This transition is analogous to a 'critical point' and intimately connects the anomalies in density and in thermodynamic response functions. Monte Carlo simulations were performed in the neighborhood of this transition and used to calculate the self diffusion constant, which increases with density as in liquid water. 相似文献
75.
Journal of Nonlinear Science - We study the existence of quasistatic evolutions for a family of gradient damage models which take into account fatigue, that is the process of weakening in a... 相似文献
76.
77.
Luciano De Vito 《Archive for Rational Mechanics and Analysis》1959,3(1):60-81
Memoria presentata da G. Fichera 相似文献
78.
Mamoci E Cavoski I Simeone V Mondelli D Al-Bitar L Caboni P 《Molecules (Basel, Switzerland)》2011,16(3):2609-2625
F. communis and D. viscosa are perennial Mediterranean weeds that have been used for different therapeutic purposes in traditional pharmacopeia. Plant extracts were obtained from air dried D. viscosa young shoots (DvA) and F. communis aerial part (FcA) and roots (FcR) with n-hexane. The chemical compositions of the extracts were analyzed by HPLC-DAD, LC-MS (ESI) and LC-Q-TOF techniques. Two sesquiterpene lactones (inuviscolide, tomentosin) and three sesquiterpene acids (costic acid, hydroxycostic acid, ilicic acid) were identified from the D. viscosa extract, while in F. communis extracts three daucane sesquiterpenes (acetoxyferutinin, oxojaeskeanadioyl anisate, fertidin) and one coumarin (ferulenol) derivates were found. Biological activities of plant extracts were studied in in vitro experiments on the colonies and conidia of Botryotinia fuckeliana, Penicillium digitatum, P. expansum, Monilinia laxa, M. fructigena and Aspergillus spp. Extracts showed varying degree of antifungal activities on colony growth and conidia germination. The extract from FcA showed the least effect, while DvA extract had the strongest fungitoxic effects. FcR extract presented a fungitoxic effect on the colony growth, but it was not able to inhibit the conidia germination. These distinctions can be attributed to the differences in chemical composition of plant extracts. 相似文献
79.
A new on-line Gd preconcentration and determination system associated to flow injection (FI) method was developed. 2,2′-(1,8-dihydroxy-3,6-disulfonaphthylene-2,7-bisazo) bisbenzenearsonic acid (Arsenazo III) was used as a complexing agent at pH 2.5. A reactor containing the polyamide membrane was used for the retention of the Gd complex by chemofiltration. The complex was then removed from the reactor with buffer solution pH 9. The variables affecting the combined on-line preconcentration-absorptiometric method have been evaluated and optimised. The coupling of the on-line preconcentration and spectrophotometric flow through detection led to a detection limit of 15 μg l−1 for a preconcentration time of 5 min at 2 ml/min. The method was successfully applied to biological samples. 相似文献
80.
G. Veneziano 《Physics letters. [Part B]》1973,43(5):413-416
Assuming that the non diffractive part of exclusive cross sections contributes to the Pomeranchuk singularity in the total cross section, we derive general relations between Regge intercepts and parameters of the multiplicity distribution. A dynamical assumption on the mechanism that generates the Pomeron gives automatically an intercept near one provided that a particular correlation parameter is small. 相似文献