Thermoelectric power of the molten systems (Cu, Ag)X (X=Cl, Br, I)

Initial thermoelectric power determinations were carried out on the molten systems (Cu, Ag)X, (X=Cl, Br, I) at 1000K. As for the employing of either copper or silver electrode thermocells, the choice was based on literature thermodynamic data. Comparison between ideal and actual behaviour allowed the authors to discover negative excess partial ionic entropies

Thermoelectric power of the molten systems PbCl 2-MeCl (Me=Li, Na, K, Rb, Cs)

Initial thermoelectric power determinations where carried out by means of Pb electrodes and Cl 2 electrode thermocells on the molten systems PbCl 2-MeCl (Me=Li, Na, K, Rb, Cs). Combinations of the results coming from the two kinds of thermocells allowed to verify Reinhold's relation (1933) and to estimate the partial molar formation and excess entropies of PbCl 2

Transient increases in intracellular calcium and reactive oxygen species levels in TCam-2 cells exposed to microgravity

The effects of microgravity on functions of the human body are well described, including alterations in the male and female reproductive systems. In the present study, TCam-2 cells, which are considered a good model of mitotically active male germ cells, were used to investigate intracellular signalling and cell metabolism during exposure to simulated microgravity, a condition that affects cell shape and cytoskeletal architecture. After a 24 hour exposure to simulated microgravity, TCam-2 cells showed 1) a decreased proliferation rate and a delay in cell cycle progression, 2) increased anaerobic metabolism accompanied by increased levels of intracellular Ca(2+), reactive oxygen species and superoxide anion and modifications in mitochondrial morphology. Interestingly, all these events were transient and were no longer evident after 48 hours of exposure. The presence of antioxidants prevented not only the effects described above but also the modifications in cytoskeletal architecture and the activation of the autophagy process induced by simulated microgravity. In conclusion, in the TCam-2 cell model, simulated microgravity activated the oxidative machinery, triggering transient macroscopic cell events, such as a reduction in the proliferation rate, changes in cytoskeleton-driven shape and autophagy activation

Thermoelectric power of the systems AgI-Ag 2XO 4 (X=Mo, W)

Determination of the initial thermoelectric power were carried out at 1000K in the whole composition range of the molten systems AgI-Ag 2XO 4 (X=Mo, W). For the composition XAgI=0.8 the investigation was extended to the variation of the thermal e.m.f. at the `melting point' of the electrochemically noteworthy glass-like phases, obtained through rapid quenching of the melt. The hypothesis that these glass-like materials could keep the melt configuration at room temperature is contradicted by the results on the molten systems; more complex interpretations, based on the behaviour of the thermal e.m.f. at the `m.p.' are proposed

Calorimetry and thermal analysis in food science : an updated review

Food science is a domain of life science. Applications of thermal analysis and calorimetry (TAC) to food products deal with many investigation targets spanning from the characterization of the systems at molecular and supramolecular level to the description of the microbial metabolism. Food products are multi-phase and multi-component metastable systems where several processes can occur simultaneously during the preparation process and the shelf life. One therefore has to disentangle various contributions to the overall instrumental outputs, using appropriate data treatments and kinetic models, and/or results from other experimental approaches. The paper reports an updated survey of TAC applications to food products through specific examples of data treatments

Transport processes in TlI and in the AgI-TlI-system

The transport properties of TlI and the system AgI-TlI were investigated by measuring the electrical conductivity, sigma, and the electronic and ionic transport numbers. A particularly high electronic conductivity was detected in beta-TlI, while the alpha phase showed a predominant anionic contribution, as in TlCl and TlBr. The intermediate compounds, AgTl 2I 3 and AgTlI 2 , are silver ion conductors, but they exhibit low sigma values. A comparison with other polyiodides, with a high silver ion conductivity, is suggested on the basis of the crystal bond ionicity

Thermoelectric power of the molten systems (Ag+Me)I and (Cu+Me)I (Me=Na, K, Rb, Cs)

The systems (Ag+Me)I and (Cu+Me)I were investigated by measuring their initial thermoelectric power; mixtures containing AgI show a behaviour much closer to the ideality than mixtures containing CuI. Interesting conclusions are suggested about the heats of transport of silver and copper ions in the pure molten iodides

Thermoelectric power and electric conductivity of the (Ag,Na)Cl and (Ag,Na)Br solid solutions

The electric conductivity and the initial thermoelectric power are determined for the solid solutions (Ag,Na)X (X=Cl,Br) over the whole composition range. Data drawn from both kinds of measurements allow to approximately estimate the contributions of cation vacancies and interstitial Ag + to the transport process. Two composition regions are distinguished: 0les NNaXles0.6 and 0.7< NNaX<1 where interstitial Ag + and cation vacancies, respectively, are prevailin

Design of critical infrastructures: application to electrical systems

The recent publication of the 5th revision of TIA 942 standard represents a benchmark framework to design resilient power systems. This standard provides a classification for electric infrastructures in terms of their capacity to tolerate failures and to allow safely maintenance operations. This ranking is not based upon technical specifications, but on system resilience level, that is the capacity to resist to an unexpected destructive event, breakdown or malfunctioning which afflicts the end user. However, this standard is provided only for design purposes. Aim of this paper is to propose an approach by which the current resilience status of a system can be evaluated, in accordance to this standard classification. The proposed technique should allow to easily analyze the gap – in terms of infrastructure topology, components and distribution lines – between an existing system and a generic configuration with a desired resilience level, and thus to suggest the steps to reach the proper availability for the system specific mission. A preliminary version of the technique – which however still leaves some open issues – has been validated with the power system infrastructure that supports one of the largest datacenters in Italy, inside a primary IT Company which has to guarantee a 24/7 continuous operation of its software application, mission critical in the interests of its customers

Quality issues impacting production planning

Among the various problems affecting production processes, the unpredictability of quality factors is one of the main issues which concern manufacturing enterprises. In make-to-order or in perishable good production systems, the gap between expected and real output quality increases product cost mainly in two different ways: through the costs of extra production or reworks due to the presence of non-compliant items and through the costs originating from inefficient planning and the need of unscheduled machine changeovers. While the first are relatively easy to compute, even ex-ante, the latter are much more difficult to estimate because they depend on several planning variables such as lot size, sequencing, deliveries due dates, etc. This paper specifically addresses this problem in a make-to-order multi-product customized production system; here, the enterprise diversifies each production lot due to the fact that each order is based on the customer specific requirements and it is unique (in example, packaging or textiles and apparel industry). In these contexts, using a rule-of-thumb in overestimating the input size may cause high costs because all the excess production will generate little or no revenues on top of contributing to increasing wastes in general. On the other hand, the underestimation of the lots size is associated to the eventual need of launching a new, typically very small production order, thus a single product will bear twice the changeover costs. With little markups, it may happen that these extra costs can reduce profit to zero. Aim of this paper is to provide a critical analysis of the literature state-of-art while introducing some elements that can help the definition of lot-sizing policies considering poor quality costs