Wilson surfaces and higher dimensional knot invariants

An observable for nonabelian, higher-dimensional forms is introduced, its properties are discussed and its expectation value in BF theory is described. This is shown to produce potential and genuine invariants of higher-dimensional knots.Comment: 31 pages, 9 figure

Loop observables for BF theories in any dimension and the cohomology of knots

A generalization of Wilson loop observables for BF theories in any dimension is introduced in the Batalin-Vilkovisky framework. The expectation values of these observables are cohomology classes of the space of imbeddings of a circle. One of the resulting theories discussed in the paper has only trivalent interactions and, irrespective of the actual dimension, looks like a 3-dimensional Chern-Simons theory.Comment: 13 page

Wilson Surfaces and Higher Dimensional Knot Invariants

An observable for nonabelian, higher-dimensional forms is introduced, its properties are discussed and its expectation value in BF theory is described. This is shown to produce potential and genuine invariants of higher-dimensional knot

222Rn daughters influence on scaler mode of the ARGO-YBJ detector

The ARGO-YBJ experiment is a full coverage air shower array; its lowest energy threshold is reached using the "scaler mode technique". Working in this mode, the signals generated by any particle hitting each cluster are put in coincidence every 150 ns and read by four independent scaler channels, giving the counting rates of multiplicity \geq1, \geq2, \geq3 and \geq4 (C1, C2, C3 and C4, respectively). The study of these counting rates pointed out a different behaviour of C1 respect to C2, C3 and C4, suggesting that C1 is detecting not only cosmic rays. This work shows that the radon (222Rn) gamma emitter daughters present in the ARGO-YBJ building air are contributing to C1 counts at the level of 1 Hz each Bq/m3 of radon. The uncertainty about this contribution is great, because of the high variability of 222Rn concentration and the building ventilation. The radon monitoring will allow the C1 correction improving the sensitivity of the ARGO-YBJ experiment at its lowest energy threshold.Comment: 4 pages, 3 figures, Proceedings of the 32nd International Cosmic Ray Conference (ICRC

Thermal behavior of a semibatch reactor during upset conditions as a function of dosing and temperature controller type

In fine chemical industries, potentially runaway reactions are often carried out in semibatch reactors to better control the heat evolution. For such processes, an uncontrolled temperature increase can trigger secondary undesired reactions or, worse, decompositions of the reacting mixture with consequent reactor pressurization and, eventually, physical explosion. For this reason, during years, it has been tried to simulate how a runaway phenomenon evolves as a consequence of a number of upset operating conditions: e.g. dosing errors, cooling system failure or external fire. In this work, a dedicated software has been developed and used to simulate a dosing error occurring during an industrial synthesis. Particularly, it has been analyzed the effect of the different industrial temperature control modes (isoperibolic and isothermal) and their related controller parameters onto the time evolution of the main process variables. Theoretical simulations have shown that dif-ferent scenarios can arise as a function of these control features

Improvement in the removal of micropollutants at Porto Marghera industrial wastewaters treatment plant by MBR technology.

This paper deals with the case of one of the most important industrial application of membrane technology in the world: the upgrading of the main industrial wastewater treatment plant (WWTP) of the petrochemical site of Porto Marghera, Northern Italy, completed on December 2005 and tested on September 2006. It describes the principal interventions of the plant upgrading and it discusses the removal obtained during the test periods for conventional pollutants as well as for micropollutants. The plant upgrading consisted of a series of improvements of the existing industrial WWTP, in order to increase the removal efficiency of the total suspended solids and the associate removal of ten micropollutant compounds, the so called forbidden substances. The most important intervention was the conversion of the existing activated sludge section into a membrane biological reactor, in order to guarantee adherence to the severe limits imposed by the special law issued to protect the Venice Lagoon, with particular reference to the mentioned 10 forbidden compounds. The experimental results and the numerous test-runs conducted confirmed the respect of the legal limits for the pollutants in the final effluent as well of the required removal rates for the different parameters. Therefore, the upgraded treatment plant was declared agreeing with the approved design

Natural levels of nitrites and nitrates in San Daniele dry cured ham PDO, and in meat, salt and sugna used for its production

The aim of the study was to determine the level of the\u201cnatural\u201dnitrite and nitrate concentration in raw meat,salt andsugna(soft pork fat) used to produce San Daniele dry cured ham (SDDCH) and in SDDCH (PDO) that hasbeen ripened over 14 months under controlled environmental conditions. The average natural nitrite content inmeat, salt,sugnaand dry cured ham was approximately 2, 1, 5 and 1 mg/kg, respectively. The natural nitratecontent was 8, 6 and 8 mg/kg. Data allowed to determine threshold value for both compounds: the nitrite andnitrate concentrations in San Daniele PDO ham must be considered\u201cnatural and not intentional added\u201dwhenthey are less than 4 and 22 mg/kg, respectively.The underlying aim of the research was to enable producers to prove no additives were deliberately addedduring the ham production and to help authorities to identify SDDCH not compliant with the r