Grafting reactions onto poly(organophosphazenes). VI. Thermooxidative stabilization of poly[bis (4-benzylphenoxy)phosphazene] by grafting acrylate polymers containing HALS groups

Poly[bist 4-benzylphenoxy phosphazene] is heated at 200 C in air and the oxidation of the 4-diphenylmethane side substituent to phosphazene-supported benzophenone, benzhydrol, and hydroperoxides is observed. The thermo-oxidative stabilization of the polymer is obtained by light-induced grafting copolymerization of the acrylic acid 2.2.6.6-tetramethyl-piperidin-4-yl ester onto the polyphosphazene substrate. The HALS moieties grafted onto the polyphosphazene films prevent the oxidative modification of the substituents and preserve the polymer against thermal damage. This process, investigated by IR. UV, and EPR spectroscopy, is basically dependent on the amount of HALS groups grafted onto the polyphosphazene matrix and on the composition of the reaction medium used to carry out the grafting process. The comparison between the thermooxidative stabilization process and the corresponding photooxidative stabilization reaction is also discussed.Presented at the 1st Italian Workshop on Cyclo- and Poly(phosphazene) Materials. Lebruary 15–16, 1996, at the CNR Research Area in Padova, Italy.     

HIRMA: Hypertextual information retrieval system managed by ARIOSTO

HIRMA results in an integrated environment to query any full-text document base system by natural language sentences, obtaining a document set relevant to the query. Moreover it supports hypertextual navigation into the document base. The system uses content based document representation and retrieval methods.

In this paper the representation framework as well as the retrieval and navigation algorithms used by HIRMA are described. Coverage and portability throughout application domains are supported by the lexical acquisition system ARIOSTO that provides the suitable lexical knowledge and processing methods to extract from raw text the semantic representation of documents content.     

Hazmat transport: a methodological framework for the risk analysis of marshalling yards

A methodological framework was outlined for the comprehensive risk assessment of marshalling yards in the context of quantified area risk analysis. Three accident typologies were considered for yards: (i) "in-transit-accident-induced" releases; (ii) "shunting-accident-induced" spills; and (iii) "non-accident-induced" leaks. A specific methodology was developed for the assessment of expected release frequencies and equivalent release diameters, based on the application of HazOp and Fault Tree techniques to reference schemes defined for the more common types of railcar vessels used for "hazmat" transportation. The approach was applied to the assessment of an extended case-study. The results evidenced that "non-accident-induced" leaks in marshalling yards represent an important contribution to the overall risk associated to these zones. Furthermore, the results confirmed the considerable role of these fixed installations to the overall risk associated to "hazmat" transportation.     

Identification of fireproofing zones in Oil&Gas facilities by a risk-based procedure

Fire is among the more dangerous accident scenarios that may affect the process and chemical industry. Beside the immediate and direct harm to workers and population, fire may also cause damages to structures, which may trigger escalation resulting in severe secondary scenarios. Fireproofing is usually applied to improve the capacity of structures to maintain their integrity during a fire. Past accidents evidenced that the available standards for fireproofing application in onshore chemical and process plants do not consider all the fire scenarios that may cause structural damage. In the present study a methodology was developed for the identification of the zones where fireproofing should be applied. The effect of both pool fires and jet fires was accounted. Simplified criteria, based on radiative heat intensity, were provided for the identification of the fire protection zones. A risk-based procedure was proposed for the selection of significant reference release scenarios to be used in the evaluation of worst credible fire consequences.     

Modelling the concentration dependence of rare earth doping in inorganic materials for optical applications: Application to rare earth doped barium aluminate

This paper reports a method for modelling the concentration dependence of rare earth doping in inorganic materials. The method is applied to barium aluminate, which when doped with rare earth ions has important optical applications as a phosphor material. Interatomic potentials are derived by fitting to the structures of barium aluminates, and used to calculate defect formation energies and thus to predict intrinsic defect disorder in the material. Solution energies for rare earth doping are then calculated, which enable the location of the dopant ions and their solubility limits to be predicted.     

Coagulation bath composition and desiccation environment as tuning parameters to prepare skinless membranes via diffusion induced phase separation

Diffusion Induced Phase Separation (DIPS) is a currently used technique to produce porous membranes for a large variety of applications. A strong limitation is represented by the occurrence of a dense skin, which is formed during the process, highly reducing the membrane permeability. To overcome this issue, two modifications of the standard DIPS protocol were investigated: the use of coagulation baths composed by a solvent/nonsolvent mixture and the desiccation in a controlled environment, by modulating the partial pressure of nonsolvent vapor. An appropriate choice of coagulation bath composition, together with an appropriate desiccation protocol (i.e., the use of a nonsolvent vapor), will produce a skinless membrane, and offers the chance to control the morphology of both membrane surfaces. These results underline the importance of post‐treatment stage in membrane preparation via phase separation, thus suggesting that membrane washing/drying stage will affect the final morphology. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42151.     

Effects of murta (Ugni molinae Turcz) extract on gas and water vapor permeability of carboxymethylcellulose-based edible films

The effect of murta (Ugni molinae Turcz) leaves extract on water vapor permeability (WVP) and gas permeability (GP) of carboxymethylcellulose (CMC)-based films was studied. Two ecotypes of murta leaves “Soloyo Grande” (SG) and “Soloyo Chico” (SC), were analyzed for their composition (HPLC-MS) and SC extract revealed a higher concentration of flavonols than the SG extract. The film forming solution was prepared with 2 g of CMC, 0.4 ml of glycerol and 0.5 ml of sunflower oil in 100 ml of water (Control), 50 ml of water and 50 ml of each exctract (SC50 or SG50) and 100 ml of each extract (SC 100 or SG 100). The addition of murta leaves extract modified the WVP and GP of the films. The WVP decreased significantly (P?0.05) with the incorporation of SG extract in the film but not with the SC extract (P>0.05). The CO₂ and O₂ permeability of the films were influenced by the kind and concentration of murta leaves extract used. The CO₂ permeability, with SG extract was higher than without extract (P?0.05) and with SC extract was not modified. The O₂ permeability with murta leaves extract were lower than without extract. Therefore, it is possible to consider that films with SC acts only as barrier to the oxygen, but with SG the water vapor and gas barrier properties were modified, being more permeable to the CO₂ and acting as barrier to O₂ and water vapor.     

Gut Microbiota Functional Traits,Blood pH,and Anti-GAD Antibodies Concur in the Clinical Characterization of T1D at Onset

Alterations of gut microbiota have been identified before clinical manifestation of type 1 diabetes (T1D). To identify the associations amongst gut microbiome profile, metabolism and disease markers, the 16S rRNA-based microbiota profiling and ¹H-NMR metabolomic analysis were performed on stool samples of 52 T1D patients at onset, 17 T1D siblings and 57 healthy subjects (CTRL). Univariate, multivariate analyses and classification models were applied to clinical and -omic integrated datasets. In T1D patients and their siblings, Clostridiales and Dorea were increased and Dialister and Akkermansia were decreased compared to CTRL, while in T1D, Lachnospiraceae were higher and Collinsella was lower, compared to siblings and CTRL. Higher levels of isobutyrate, malonate, Clostridium, Enterobacteriaceae, Clostridiales, Bacteroidales, were associated to T1D compared to CTRL. Patients with higher anti-GAD levels showed low abundances of Roseburia, Faecalibacterium and Alistipes and those with normal blood pH and low serum HbA_1c levels showed high levels of purine and pyrimidine intermediates. We detected specific gut microbiota profiles linked to both T1D at the onset and to diabetes familiarity. The presence of specific microbial and metabolic profiles in gut linked to anti-GAD levels and to blood acidosis can be considered as predictive biomarker associated progression and severity of T1D.