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81.
3-Hydroxy-1-phenyl-2-pyrazolin-5-one 1 reacts with primary, secondary and allylic alcohols under catalytic acidic conditions and in the presence of 3 Å molecular sieves, to afford 3-alkoxy-1-phenyl-2-pyrazolin-5-ones 3 . 相似文献
82.
Summary This work reports a rapid and easy procedure for the analysis of the aromatic fraction in gasoline. No sample pretreatment is required, since the gasoline is diluted in methanol and directly injected into a liquid chromatograph. A spectrophotometer detector and a spectrofluorimeter detector are used in series. The procedure has been applied to a large number of Italian and European refined gasoline samples.Dedicated to Prof. Dr. A. Liberti on the occasion of his 70th birthday. 相似文献
83.
D. Acierno F.P. La Mantia G. Marrucci G. Rizzo G. Titomanlio 《ournal of non Newtonian Fluid Mechanics》1976,1(2):147-157
A model of non-linear viscoelasticity with relaxation times which depend on the structure is compared with experimental results reported in the literature for a L.D. polyethylene.The single parameter of the model is determined by comparison with steadystate shear results. The model is then used to interpret various transient data. These are: tangential and normal stress growth in shear, stress growth in elongation, normal stresses in shear creep.The comparison shows a good general agreement, thus supporting the suggestion of relating the change in time of the relaxation spectrum to structural variables. 相似文献
84.
A method of accounting for the influence of body force, which involves a surface rather than a volume integral, is shown to be available whenever the body force is derivable from a scalar with constant Laplacian.
Zusammenfassung Es wird gezeigt, dass man die Raumkraft durch ein Oberflächenintegral darstellen kann, falls sie sich von einem Skalarfeld mit konstantem Laplace Operator herleiten lässt.相似文献
85.
We analyze several patterns of symmetry breaking of SO(10) where SU(3)c × SU(2) × U(1) × U(1) is an intermediate energy subgroup. Using constraints from the renormalization group and data from neutral-current experiments we show that if the only Higgs used in the low-energy breaking of the theory are those which can give mass to fermions then the possibility of a low intermediate mass scale is ruled out. 相似文献
86.
M. Papa G. Cardella A. Di Pietro S. L. Li A. Musumarra G. Pappalardo F. Rizzo A. De Rosa G. Inglima M. La Commara D. Pierroutsakou M. Romoli 《Zeitschrift für Physik A Hadrons and Nuclei》1995,353(2):205-212
The properties of the strong fluctuations observed in the excitation functions of Dissipative Binary Heavy Ion Collisions (DBHIC) have been studied for the system28Si+28Si in the energy range 150 MeV ≤E lab ≤ 156 MeV with 150 keV step laboratory incident energy, by angular distributions and excitation functions measurements. Experimental results are compared to the the recently developed Partially Overlapping Molecular Level Model (POMLM). The parameters of the model have been determined with reasonable accuracy by describing all the quantities characterizing the fluctuations in the excitation functions i.e.: Average Angular Distributions, Energy Autocorrelation Functions, Variances, Angular Correlation Coefficients. The results of the analysis strongly support the idea of a process proceeding through the formation of an highly excited “nuclear molecule”. Experimental data collected at the most forward angles show the effects of strong excitation of a few final channels. 相似文献
87.
Hawtin P Hardern I Wittig R Mollenhauer J Poustka A Salowsky R Wulff T Rizzo C Wilson B 《Electrophoresis》2005,26(19):3674-3681
On-chip electrophoresis can provide size separations of nucleic acids and proteins similar to more traditional slab gel electrophoresis. Lab-on-a-chip (LoaC) systems utilize on-chip electrophoresis in conjunction with sizing calibration, sensitive detection schemes, and sophisticated data analysis to achieve rapid analysis times (<120 s). This work describes the utility of LoaC systems to enable and augment systems biology investigations. RNA quality, as assessed by an RNA integrity number score, is compared to existing quality control (QC) measurements. High-throughput DNA analysis of multiplex PCR samples is used to stratify gene sets for disease discovery. Finally, the applicability of a high-throughput LoaC system for assessing protein purification is demonstrated. The improvements in workflow processes, speed of analysis, data accuracy and reproducibility, and automated data analysis are illustrated. 相似文献
88.
Aurora Fernandez G. Gregory A. Hindle A. C. Lee 《The Journal of the Operational Research Society》1974,25(2):231-239
A model for the working day of the community nurse is proposed. This takes into account the attachment of the nurse to the patients registered with assigned general practices and the effect that this will have on her travelling time, visiting time and administrative duties. It also leads to a method of dividing the country into nursing team regions, assessing the level of nursing service thereby provided. 相似文献
89.
90.
Tommaso Rizzo Alejandro Lage-Castellanos Roberto Mulet Federico Ricci-Tersenghi 《Journal of statistical physics》2010,139(3):375-416
We present a general formalism to make the Replica-Symmetric and Replica-Symmetry-Breaking ansatz in the context of Kikuchi’s
Cluster Variational Method (CVM). Using replicas and the message-passing formulation of CVM we obtain a variational expression
of the replicated free energy of a system with quenched disorder, both averaged and on a single sample, and make the hierarchical
ansatz using functionals of functions of fields to represent the messages. We obtain a set of integral equations for the message
functionals. The main difference with the Bethe case is that the functionals appear in the equations in implicit form and
are not positive definite, thus standard iterative population dynamic algorithms cannot be used to determine them. In the
simplest cases the solution could be obtained iteratively using Fourier transforms. 相似文献