The method employing dimolybdenum tetraacetate for the assignment of the absolute configuration of optically active 1,2-diols is thoroughly revisited and applied to several compounds, some of which were synthesized by asymmetric cis-dihydroxylation. No exceptions were found to the empirical rule relating the sign of the induced CD spectrum and the configuration of the substrate, whatever its structure and sterical requirements. To broaden the scope of the method, its applicability to critical situations commonly encountered with synthetic products is tested. It is demonstrated that the method can be applied on samples with low chemical and optical purity, and that it may lend itself as a means to estimate the ee. The roles of the water content of the sample and of the diol-to-dimolybdenum ratio are investigated.

In the last forty, years semi-flexible pavements have been successfully employed, especially in those areas subjected to heavy and slow-moving loads. They usually comprise a wearing course of Grouted Macadam, a composite pavement material that provides significant advantages in comparison to both concrete and asphalt pavements. On the other hand, the laying process of this material is a two-stage operation, and the realization complexity leads to long realization times and high initial costs. Therefore, the use of semi-flexible pavements has been limited to some fields of application and areas. Recently, an innovative material has been developed to be used as an alternative to Grouted Macadam for semi-flexible pavement wearing course realization. This material should provide similar or even superior characteristics compared to traditional Grouted Macadam. This will reduce semi-flexible pavement construction time and avoid the need for dividing the laying process. This paper presents an experimental program involving the use of FastFWD, as an APT device, to evaluate in-situ properties and performance of this material. The achieved results regarding the validation of this new material by means of FastFWD appear promising both in terms of the material’s properties and resistance to dynamic load repetitions.

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In this paper, a new methodology for the assessment of the so-called “acoustic capacity” of a road infrastructure is proposed. This aspect is very important in the field of transportation planning as, currently, road infrastructures are verified only in terms of physical capacity; at most, the environmental capacity due to atmospheric pollutants is taken into account, while the acoustic capacity is completely neglected. The acoustic capacity is assessed based on the Harmonoise model, which is widely recognized at the European level. The Harmonoise model, starting from traffic data, such as traffic flows, average speed, and typologies of vehicles, provides the levels of noise emissions and immissions, which can be compared to the noise limit levels established by law. The validity of the proposed methodology was assessed on a test network. The results of this analysis show that, generally, the acoustic capacity is actually a capacity constraint, which involves several traffic flows: this occurs in particular in the case of an intersection, but also in the case of a bi-directional road. Furthermore, the acoustic capacity of a road infrastructure is generally lower than its physical capacity.

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