The integrated low-level trigger and data acquisition (TDAQ) system of the NA62 experiment at CERN is described. The requirements of a large and fast data reduction in a high-rate environment for a ...medium-scale, distributed ensemble of many different sub-detectors led to the concept of a fully digital integrated system with good scaling capabilities. The NA62 TDAQ system is rather unique in allowing full flexibility on this scale, allowing in principle any information available from the detector to be used for triggering. The design concept, implementation and performances from the first years of running are illustrated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The thermal stability of blends obtained from the mixture of 4-dodecylbenzenesulfonic acid doped polyaniline (PANI(DBSA)) and a terpolymer of ethylene-propylene-5-ethylidene-2-norbornene (EPDM) by ...casting from organic solvents, was studied by thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR) under nitrogen atmosphere. For the PANI(DBSA) complex and PANI(DBSA)/EPDM blends the TGA results showed more than one stage of degradation, of which the second (temperature range 380–520 °C) was observed to be the most significant. Apparently, in this stage, the simultaneous degradation of the bound dopant, the PANI and the elastomer occurred. The activation energy (
E) for the crosslinked blends was in the range 180–250 kJ mol
−1, higher values than those determined for pure components and non crosslinked blends which were in the range 150–210 kJ mol
−1. The
E values also indicated that the effects due to the PANI(DBSA) content and maleated EPDM were not significant and that the mechanism of degradation of both systems studied was associated with a random scission of the chain. The FTIR spectra for the PANI(DBSA)/EPDM crosslinked blend showed typical absorption bands associated with saturated and unsaturated hydrocarbons, water, carbon dioxide and nitrogen containing compounds.
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The thermal stability of poly(
N-vinyl-2-pyrrolidone-co-methacrylic acid) copolymers was studied by thermogravimetry and infrared spectroscopy in inert atmosphere. The thermogravimetric curves ...suggested that the effective degradation of both systems occurred in the temperature range 350–500 °C with more than 60% mass loss. At this temperature, the activation energy was in the range 160–200 kJ mol
−1 (average values), suggesting that the degradation occurred by a random scission of the chain. The FTIR results indicated that the main volatile products of degradation are CO
2, CO and hydrocarbons (unsaturated structures) with low molecular weight. Pure PVP also showed the formation of NH
3 which was apparently suppressed in the copolymer by the formation of large amounts of CO
2 and CO. The results suggested that the thermal stability of the copolymers was essentially associated with the
N-vinyl-2-pyrrolidone monomer, losing stability when the percentage of methacrylic acid in the copolymer system was increased.
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Polylactic acid (PLA) has been larger used in biomedical field due to its low toxicity and biodegradability. The aim of this study was to produce PLLA nanocomposites, by melt extrusion, containing ...Halloysite nanotubes (HNT) and/or titanium dioxide (TiO2) nanoparticles. Immediately after drying, PLLA was mechanically homogenized with the nanofillers and then melt blended using a single screw extruder (L/D 30) at a speed of 110 rpm, with three heating zones in which the following temperatures were maintained: 150, 150 and 160°C (AX Plasticos model AX14 LD30). The film samples were obtained by compression molding in a press with a temperature profile of 235 ± 5°C for 2.5 min, after pressing, films were cooled up to room temperature. The mechanical tests were performed according to ASTM D882-09 and the water vapor permeability (WVP) was measured according to ASTM E-96, in triplicate. The tensile properties indicated that the modulus was improved with increased TiO2 content up to 1g/100g PLLA. The Young's modulus (YM) of the PLA was increased from 3047 MPa to 3222 MPa with the addition of 1g TiO2/100g PLLA. The tensile strength (TS) of films increases with the TiO2 content. In both cases, the YM and TS are achieved at the 1% content of TiO2 and is due to the reinforcing effect of nanoparticles. Pristine PLA showed a strain at break (SB) of 3.56%, while the SB of nanocomposites were significant lower, for instance the SB of composite containing 7.5 g HNT/100g PLLA was around 1.90 %. The WVP of samples was increased by increasing the nano filler content. It should be expected that an increase of nanofiller content would decrease the mass transfer of water molecules throughout the samples due to the increase in the way water molecules will have to cross to permeate the material. However, this was not observed. Therefore, this result can be explained considering the molecular structure of both fillers, which contain several hydroxyl groups in the surface, making the end material more hydrophilic.
The effects of maleated ethylene propylene diene (EPDM-g-MA) on the thermal stability of polyamide/EPDM and polyamide/poly(ethylene terephthalate) (PET) systems were studied by thermogravimetric ...analysis and infrared spectroscopy in nitrogen. Based on the activation energy (
E) and reaction products, it is suggested that the thermal degradation of pure polyamide 12.10 (PA-12.10) and polyamide 6.10 (PA-6.10) occurred firstly by chain scission of the weakest C–N and –C(O)–NH bonds. The average value of
E for pure PA-12.10 was ca. 280 kJ mol
−1. In the binary and ternary blends, the decrease of
E to ca. 180–200 kJ mol
−1 indicated a more favourable degradation. For the systems containing PA-6.10,
E decreased from ca. 210 kJ mol
−1 (pure PA-6.10) to ca. 160 kJ mol
−1 in the ternary blends. The results suggest that the presence of EPDM-g-MA in the blend decreased the thermal stability of the polyamides.
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Studies on elemental analysis, Fourier transform infrared spectroscopy (FT-IR) and thermal decomposition (thermogravimetry, TG; and derivative thermogravimetry, DTG) of sedimentary fulvic (FA) and ...humic acids (HA) from marine, estuarine, lacustrine and terrestrial environments are presented. In general, H/C and N/C atomic ratios, as well as the infrared spectra, reflected the extent of the influence of algal and/or terrestrial organic matter sources on the samples, the aquatic (both, marine and freshwater) humic substances (HS) being richer in nitrogen and more saturated, than terrestrial materials. Comparison of properties of FA and HA from the same parent sediments showed that the latter are relatively richer in nitrogen and unsubstituted aliphatic chains and poorer in carboxylic groups. FT-IR spectra showed that the nitrogen present is mostly as forming part of amide groups. Concerning thermal degradation, two main steps were observed for all samples: the first, relative to the loss of moisture, being located between 40°C and 100°C and the second between 270°C and 440°C. FT-IR spectra of the samples which had been heated to 90°C, 400°C and 900°C showed that, upon heating, the carboxyl content decreases (especially for FA), the aliphaticity decreases and the aromaticity increases (especially for HA), indicating that the 270°C-470°C degradation step might be related to decarboxylation and unsaturation losses. In spite of this, both kinds of HS, were shown to be highly thermo-resistant materials retaining most of their typical original infrared spectral features, even after being heated to 400°C.
Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, ...meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 °C and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 °C by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelf- life. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruits.
The thermal degradation of 2-hydroxy-3-ionene chloride polymer (HICP) and 3,22-ionene bromide (3,22) was studied in nitrogen atmosphere by thermogravimetry (TG) and infrared spectroscopy (FTIR). For ...the two polymers, a different profile in the TG/DTG curves was observed which was probably associated with the structural and functional differences between HICP and 3,22. The
E-values decreased from 150 to 105 kJ mol
−1 for the HICP and increased from 110 to 140 kJ mol
−1 for the 3,22 in the same range of weight loss fraction. The observed behaviour in terms of the TG/DTG curves and the activation energy values suggested that the 3,22 is more stable thermally than the HICP. This conclusion was supported by the FTIR spectra of the residues and evolved gas products of degradation. The mechanism of degradation was apparently associated with the scission of weak bonds and random scission of the polymer chain. Evolved gas products such as CO
2 and NH
3 in HICP and unsaturated hydrocarbons in 3,22 confirm the above mechanism.
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Hard X-ray (≥10 keV) observations of active galactic nuclei (AGNs) can shed light on some of the most obscured episodes of accretion onto supermassive black holes. The 70-month Swift/BAT all-sky ...survey, which probes the 14-195 keV energy range, has currently detected 838 AGNs. We report here on the broadband X-ray (0.3-150 keV) characteristics of these AGNs, obtained by combining XMM-Newton, Swift/XRT, ASCA, Chandra, and Suzaku observations in the soft X-ray band ( keV) with 70-month averaged Swift/BAT data. The nonblazar AGNs of our sample are almost equally divided into unobscured ( ) and obscured ( ) AGNs, and their Swift/BAT continuum is systematically steeper than the 0.3-10 keV emission, which suggests that the presence of a high-energy cutoff is almost ubiquitous. We discuss the main X-ray spectral parameters obtained, such as the photon index, the reflection parameter, the energy of the cutoff, neutral and ionized absorbers, and the soft excess for both obscured and unobscured AGNs.
We report on the preparation and properties of soy protein isolate (SPI)‐sodium dodecyl sulfate (SDS)‐polycaprolactone‐triol (PCL‐T) films obtained by solvent casting from solutions containing ...variable amounts of SDS or SDS/PCL‐T. It is shown that the mechanical and thermal properties, and the morphology of SPI‐based biofilms can be easily controlled by changing SDS, PCL‐T, and moisture contents, enabling the fabrication of rigid and flexible materials as pure SPI films Young's modulus ∼ 1 400 MPa, elongation at break (E) ∼ 2%, and glass transition temperature (Tg) ∼ 150 °C and SPI/SDS/PCL‐T films with PCL‐T ≥ 18% (Young's modulus ∼ 50 MPa, E ∼ 90%, and Tg ∼ 135 °C), respectively. Micrographs taken at the cross‐section of biofilms whose PCL‐T ≥ 18% revealed the occurrence of a porous matrix, whereas a dense bulk phase was otherwise observed (pure SPI, SPI/SDS, and SPI/SDS/PCL‐T films with PCL‐T < 18%).
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