Integrated Gasification Combined Cycle (IGCC) represents a commercially proven technology available for the combined production of hydrogen and electricity power from coal and heavy residue oils. ...When associated with CO2 capture and sequestration facilities, the IGCC plant gives an answer to the search for a clean and environmentally compatible use of high sulphur and heavy metal contents fuels, the possibility of installing large size plants for competitive electric power and hydrogen production, and a low cost of CO2 avoidance.
The paper describes two new and realistic configurations of IGCC plant fed by refinery heavy residues and including a CO2 capture section, which are proposed on the basis of the experience gained in the construction of similar plants. They are based on oxygen blown entrained bed gasification and sized to produce a large amount of hydrogen and to feed one or two gas turbines of the combined cycle unit. The main thermodynamic and technological characteristics of the total plants are evaluated focusing on the heat integration between syngas cooling and combined cycle sections.
Moreover, the overall performance characteristics and investment cost are estimated to supply a reliable estimate for the cost of electricity, given a value for the hydrogen selling price.
We present a new measurement of $J/\psi$ production in Pb-Pb collisions at 158 GeV/nucleon, from the data sample collected in year 2000 by the NA50 Collaboration, under improved experimental ...conditions with respect to previous years. With the target system placed in vacuum, the setup was better adapted to study, in particular, the most peripheral nuclear collisions with unprecedented accuracy. The analysis of this data sample shows that the ($J/\psi$)/Drell-Yan cross-sections ratio measured in the most peripheral Pb-Pb interactions is in good agreement with the nuclear absorption pattern extrapolated from the studies of proton-nucleus collisions. Furthermore, this new measurement confirms our previous observation that the ($J/\psi$)/Drell-Yan cross-sections ratio departs from the normal nuclear absorption pattern for semi-central Pb-Pb collisions and that this ratio persistently decreases up to the most central collisions.
We report a new measurement of J/ψ, ψ′ and Drell–Yan cross-sections, in the kinematical domain -0.425<ycm<0.575 and -0.5<cosθCS<0.5, performed at the CERN-SPS using 400 GeV/c incident protons on Be, ...Al, Cu, Ag, W and Pb targets. The dependence of the charmonia production cross-sections on the size of the target nucleus allows to quantify the so-called normal nuclear absorption. In the framework of the Glauber model, this new measurement is combined with results previously obtained with the same apparatus, under different experimental conditions, and leads to a precise determination of the J/ψ and ψ′ absorption cross-sections in the surrounding nuclear matter.
ABSTRACT The presented study aimed to assess objectively the response of distal interphalangeal joint (DIJ), navicular bursa (NB) and deep digital flexor tendon sheath (DDFTS) anesthesia in horses ...with forelimb hoof lameness; and evaluate if the presence of radiographic abnormalities on navicular bone could interfere on blocks’ results. Fifteen horses with lameness improvement above 70% after palmar digital nerve (PDN) block were selected for this study. Blocks were assessed separately on five consecutive trials at seven different time-points. The fifth trial was performed to evaluate the influence of exercise on preexisting lameness. Most of horses (73.33%) presented pain related to the podotrochlear apparatus based on clinical and lameness exam and blocks’ responses. NB and DIJ anesthesia differed on the frequency of horses with lameness improvement above 70% only at 10min (p=0.03), and both differed from DDFTS block until 30’(p<0.05). The blocks’ response was variable along the time and the highest means for NB, DIJ and DDFTS were observed at 5-10 minutes (’), 15-20’ and 10-15’ respectively.Exercise had low interference on lameness intensity since no improvement above 50% was observed and an increase on lameness intensity over time was identified in seven horses. Variable grades of navicular bone radiographic lesions were observed in 14 horses, although these lesions had no interference on blocks’ response (p>0.05). The NB and DIJ blocks had similar responses and both were superior to DDFTS anesthesia, coincident with a major prevalence of podotroclear apparatus abnormalities in this equine population.
RESUMO O presente estudo avaliou, de forma objetiva, as respostas do bloqueio da articulação interfalangeana distal (AID), da bursa do navicular (BN) e da bainha do tendão flexor digital profundo (BTFDP) em equinos com claudicação ligada ao casco nos membros torácicos; além de analisar a influência das alterações radiográficas do osso navicular no resultado dos bloqueios. Quinze cavalos, que apresentaram uma melhora da claudicação acima de 70% após o bloqueio do nervo digital palmar, foram selecionados para este estudo. Os bloqueios foram avaliados separadamente em cinco turnos consecutivos e em sete tempos diferentes. O quinto turno foi utilizado para analisar a influência do exercício sobre a claudicação preexistente. A maioria dos cavalos (73,33%) apresentou dor relacionada à porção palmar do casco, com base nos achados do exame clínico em movimento e nas respostas dos bloqueios. As anestesias da BN e da AID apresentaram diferença quanto à frequência de cavalos com melhora da claudicação acima de 70% apenas aos 10min (p=0.03), e ambos diferiram do bloqueio da BTFDP até os 30min (p<0.05). A resposta dos bloqueios foi variada ao longo do tempo, e as maiores médias de melhora da claudicação para os bloqueios BN, AID e BTFDP foram observadas aos 5-10min, 15-20min e 10-15min, respectivamente. O exercício teve pequena interferência na intensidade da claudicação, uma vez que nenhuma melhora acima de 50% foi observada e sete cavalos aumentaram a intensidade da claudicação ao longo do tempo. A presença de diferentes graus de lesão radiográfica do osso navicular foi observada em 14 cavalos, porém essas lesões não interferiram na resposta dos bloqueios (p>0,05). Os bloqueios da BN e da AID apresentaram respostas semelhantes, e ambos foram superiores ao bloqueio da BTFDP, coincidindo com uma marcada prevalência de doença do aparato podotroclear nesta população de equinos.
ψ′ production is studied in Pb–Pb collisions at 158 GeV/c per nucleon incident momentum. Absolute cross-sections are measured and production rates are investigated as a function of the centrality of ...the collision. The results are compared with those obtained for lighter colliding systems and also for the J/ψ meson produced under identical conditions.
The cross sections of forward emission of one, two and three neutrons by 158A GeV 115In nuclei in collisions with Al, Cu, Sn and Pb targets are reported. The measurements were performed in the ...framework of the ALICE–LUMI experiment at the SPS facility at CERN. Various corrections accounting for the absorption of beam nuclei and produced neutrons in target material and surrounding air were introduced. The corrected cross section data are compared with the predictions of the RELDIS model for electromagnetic fragmentation of 115In in ultraperipheral collisions, as well as with the results of the abrasion–ablation model for neutron emission in hadronic interactions. The measured neutron emission cross sections well agree with the RELDIS results, with the exception of In–Al collisions where the measured cross sections are larger compared to RELDIS. This is attributed to a relatively large contribution of hadronic fragmentation of In on Al target with respect to electromagnetic fragmentation, in contrast to similar measurements performed earlier with 30A GeV 208Pb colliding with Al.
This study aimed to evaluate the influence of the track surface on which horses are examined, regarding the phase of lameness presentation. Ten horses with lameness in at least one limb were ...evaluated with wireless inertial sensors on three track surfaces (concrete, loose sand and grass). Six crossover track sequences were established. The variables vector sum, maximum and minimum height of the head and pelvis, variation coefficient of the maximum and minimum height of the head and pelvis were analyzed using ANOVA, followed by Tukey test to compare means between track surface and sequence, at 5% significance level. The lameness phase (impact or pushoff) was analyzed considering the proportion of affected animals. There were no differences on vector sum, maximum and minimum height or variation coefficient of head and pelvis. Difference was observed on the number of strides registered on sand compared to grass and concrete (p <0.0001) for fore and hindlimbs. Impact lameness on forelimbs was presented by a larger number of animals on the concrete surface; pushoff lameness was more evident on the grass surface. In the hindlimbs, impact lameness was more evident on the grass surface, while pushoff lameness was in greater number of animals on concrete surfaces. The track sequence on which horses were trotted during evaluation does not seem to be a factor, but the number of lame horses and the phase of lameness manifestation can vary between track surfaces, as some horses showed impact lameness on soft ground and elevation lameness on hard ground.
RESUMO Este estudo teve como objetivo avaliar a influência do tipo de superfície em que os cavalos são examinados em relação à fase de apresentação da claudicação. Dez cavalos com claudicação em pelo menos um dos membros foram avaliados com sensores inerciais sem fio em três tipos de superfície (concreto, areia e grama). Seis sequências de cruzamento de tipo de superfície foram estabelecidas. As variáveis soma vetorial, altura máxima e mínima da cabeça e da pélvis, o coeficiente de variação da altura máxima e mínima da cabeça e da pélvis foram analisadas utilizando uma Análise de Variância, seguida do teste de Tukey para comparação das médias entre tipos de superfície e sequências, a um nível de significância de 5%. A fase da claudicação (impacto ou elevação) foi analisada considerando a proporção de animais afetados. Não houve diferença na soma vetorial, altura máxima ou mínima e coeficiente de variação da altura máxima e mínima da cabeça e pélvis. Foi observada diferença no número de passos registrados na areia em comparação com grama e concreto (p <0,0001) para membros torácicos e pélvicos. Claudicação de impacto nos membros torácicos foi apresentada em um número maior de animais na superfície de concreto, já claudicação de elevação foi mais evidente na superfície de grama. Em membros pélvicos, a claudicação de impacto foi mais evidente na superfície de grama, enquanto claudicação de elevação esteve em maior número de animais na superfície de concreto. A sequência de superfícies em que os cavalos foram troteados durante a avaliação não foi um fator importante na manifestação da claudicação, mas o número de cavalos claudicantes e a fase de manifestação da claudicação podem variar entre as superfícies, visto que alguns cavalos mostraram claudicação de impacto em solo macio e claudicação de elevação em solo duro.
The zero degree calorimeters for the ALICE experiment Puddu, G.; Arnaldi, R.; Chiavassa, E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2007, Letnik:
581, Številka:
1
Journal Article
Recenzirano
The Zero Degree Calorimeters (ZDC) for the ALICE experiment will measure the energy of the spectator nucleons in heavy ion collisions at the CERN LHC, providing a direct measure of the centrality of ...the collisions. ZDC are spaghetti calorimeters, which detect the Cherenkov light produced by the shower particles in silica optical fibers embedded in a dense absorber. The main characteristics of the ZP and ZN detectors are described in this article. The calorimeters were tested at the CERN SPS using pion and electron beams with momenta ranging from 50 to
200
GeV
/
c
. Test beam results such as the calorimeter response, the energy resolution, the signal uniformity and the localizing capability are presented.
The Neutron Zero Degree Calorimeter for the ALICE experiment Arnaldi, R.; Chiavassa, E.; Cicalò, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2006, Letnik:
564, Številka:
1
Journal Article
Recenzirano
In this paper, we present the performance of the Neutron Zero Degree Calorimeter (ZN) for the ALICE experiment. The ZN is a quartz-fiber spaghetti calorimeter, which will measure the energy of the ...spectator neutrons in heavy ion collisions at the CERN LHC. Its principle of operation is based on the detection of the Cherenkov light produced by the charged particles of the shower in silica optical fibers, embedded in a W-alloy absorber. The detector was tested at CERN SPS using positive hadron and positron beams with momenta ranging from 50 to
150
GeV
/
c
. The response of the calorimeter, the energy resolution, the localizing capability, the signal uniformity and the transverse profile of the detectable hadronic shower are presented.
ALICE at the CERN LHC will investigate the physics of strongly interacting matter at extreme energy densities where the formation of the Quark Gluon Plasma is expected. Its properties can be studied ...from observations like the production of mesons with charm and beauty quarks. These signals have to be studied as a function of energy density, which is determined by the centrality of collisions. One of the physics observables that is closely related with the centrality of the collision is the number of spectator nucleons that can be measured by the Zero Degree Calorimeters (ZDC). Having a direct geometric interpretation allows to extract the impact parameter with minimal model assumptions. This paper describes the readout system of the ZDC. The ZDC readout consists of a VME system with a ZDC Readout Card, a VME Processor, Discriminators, a ZDC Trigger Card, scalers, QDCs and TDCs. The system was successfully tested during the 2009 ALICE data taking and is currently operational at the LHC.
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