Alternative biofuels:PVTx measurements for DME + propane

This study presents the experimental results for the dimethyl ether (DME) ? propane system obtained using the Burnett method. The apparatus was calibrated using helium. PVTx measurements were taken for four isotherms (344, 354, 364, and 375 K), performing 16 Burnett expansions in pressures ranging from about 3,000 to 70 kPa. The second and third virial coefficients were derived from experimental results. The experimental uncertainty in the second and third virial coefficients was estimated to be within ±5 cm 3/mol and ±1,000 cm6/mol2,respectively

PVT properties of an alternative biofuel: dimethyl ether

Dimethyl ether is an important chemical material and it has many engineering applications. It is a clean and economical alternative fuel and an ozone-friendly refrigerant. In this work, its PVT properties have been object of study. In particular, the experimental work was performed both in the two-phase region and in the superheated vapor region phase by means of the isochoric method. The isochoric measurements were carried out at temperatures from 219 K to 363 K and at pressures from 22 kPa up to 1,740 kPa. A total of 159 points, both in the two phase (71 points) and in the superheated vapor region (88 points) were obtained. The present experimental PVT data contribute to the deeper knowledge of the behaviour of the fluid both in the superheated vapour and in the saturation pressure region and to the development of a new equation of state

Finding synergies for the 3Rs – Repeated dose toxicity testing: Report from an EPAA partners' forum

The European Partnership for Alternative Approaches to Animal Testing (EPAA) convened a Partners' Forum on repeated dose toxicity (RDT) testing to identify synergies between industrial sectors and stakeholders along with opportunities to progress these in existing research frameworks. Although RTD testing is not performed across all industrial sectors, the OECD accepted tests can provide a rich source of information and play a pivotal role for safety decisions relating to the use of chemicals. Currently there are no validated alternatives to repeated dose testing and a direct one-to-one replacement is not appropriate. However, there are many projects and initiatives at the international level which aim to implement various aspects of replacement, reduction and refinement (the 3Rs) in RDT testing. Improved definition of use, through better problem formulation, aligned to harmonisation of regulations is a key area, as is the more rapid implementation of alternatives into the legislative framework. Existing test designs can be optimised to reduce animal use and increase information content. Greater use of exposure-led decisions and improvements in dose selection will be beneficial. In addition, EPAA facilitates sharing of case studies demonstrating the use of Next Generation Risk Assessment applying various New Approach Methodologies to assess RDT

Experimental analysis of natural convection in square cavities heated from below with 2D-PIV and holographic interferometry techniques

A numerical and experimental analysis was performed to study the natural convection heat transfer in a square cavity heated from below and cooled by the sidewalls. The enclosure was filled with air (Pr = 0.71) and a discrete heater was mounted on its lower surface; the effect of three different positions was evaluated. The air temperature distribution and the Nusselt numbers at different Rayleigh numbers on the heated strip were measured by an holographic interferometry thanks to the real-time and the double-exposure technique. The double-exposure technique was performed at steady-state and it was used to obtain the isothermal lines in the cavity at different Rayleigh numbers; while the real-time technique was used to control the presence of the plume oscillations and to determinate the achievement of the steady-state. A 2D particle image velocimetry (PIV) was utilized to measure the velocity fields at the same Rayleigh numbers. In particular we analysed the distribution of the velocity vectors and their modulus inside the cavity. The convective phenomenon was studied and the Nusselt numbers were presented as well as the Rayleigh numbers analysed. Moreover experimental and numerical correlations were determined for each position analysed to connect the Rayleigh numbers with the Nusselt numbers. Measured quantities were compared with the numerical results which were obtained with the finite volume code Fluent 6.2.16

APAF1 (apoptotic protease activating factor 1)

Review on APAF1 (apoptotic protease activating factor 1), with data on DNA, on the protein encoded, and where the gene is implicated

The Natural Convective Heat Transfer in a Partially Divided Enclosure: A Study on the Influence of the Source Position

The aim of this paper is to analyse the natural convective heat transfer generated by a source with a height of ζ located in two different positions inside a square enclosure of side H. In the first case, δ is 0.5 of H while in the second case it is 0.4. The comparison is based both on the evaluation of the local and average Nusselt numbers at different Rayleigh numbers and on the study of the velocity fields at the same Rayleigh numbers in the two different configurations. The experimental analysis was carried out through a holographic interferometry, to study the heat transfer, and through a 2D-PIV system, to analyse the dynamic behaviour of the phenomenon. Finally, for δ = 0.5 we compared the experimental results with those obtained through the volume finite software Fluent 6.3.26. In the analysis, it is possible to see that the position of the source influences both the average Nusselt numbers on the hot surfaces and the development of a small bubble on the upper surfac

A numerical and experimental analysis on the natural convective heat transfer of a small heating strip located on the floor of a square cavity

In this paper it is analyzed the influence of the position of a small heating source placed on the bottom wall of a square cavity filled by air (Pr = 0.71). We studied a strip of a determined dimensionless length of ε = 1/5 that is located at two different dimensionless distances from the left side of the cavity: the first one is δ = 0.4 (asymmetrical position) and the second one is δ = 0.5 (symmetrical position). The experimental analysis was carried out through an holographic interferometry and through a 2D PIV system. The holographic interferometry was used by the real-time technique and by the double-exposure technique. In the first case we analyzed the presence of the plume oscillations and we determined the achievement of the steady state; in the second case we concentrated on the air temperature distributions, consequently we measured the Nusselt numbers on the heated strip at different Rayleigh numbers. The experimental study also included an analysis through a 2D Particle Image Velocimetry (PIV), that allowed us to measure the velocity fields and the dynamic structures generated by the heat transfer at the same Rayleigh numbers. Measured quantities were compared with the numerical results which were obtained through the finite volume code Fluent 6.2.1

Distinctive roles of PHAP proteins and prothymosin-alpha in a death regulatory pathway

[No abstract available