749 research outputs found
Intensifying glycerol steam reforming on a monolith catalyst: a reaction kinetic model
In this work, a structured monolithic catalyst has been tested under a wide range of conditions (partial pressure, residence time, temperature and time-on-stream), with the aim of modeling its kinetic behavior and assessing its economic and upscaling potential. We have developed a sequential model to help us interpret both main trends and salient features. Unexpected behavior was found for certain parameter values, which led us to consider kinetic parasitic effects such as mass or heat transfer limitations. By independently invoking these effects, a conciliatory view of the results observed could not be reached. A combined explanation may prove successful, although overfitting could not be ruled out at this point. More importantly, however, the observed salient features of this stable and selective monolith catalyst may hold potential for process intensification of glycerol steam reforming, thus contributing to a more sustainable industry.Ministerio de Economía y Competitividad ENE2013-47880-C3-2-R, ENE2015-66975-C3-2-
Assessing production constraints and farmer preference for sweetpotato through a PRA study and structured survey.
First observations of the X-ray transient EXO 2030+375 with IBIS/ISGRI
We present a first INTEGRAL observation of the 42s transient X-ray pulsar EXO
2030+375 with IBIS/ISGRI. The source was detected during Cyg X-1 observations
in December 2002. We analyzed observations during the outburst period from 9 to
21 December 2002 with a total exposure time of ~770 kiloseconds. EXO 2030+375
was almost always detected during single ~30 minute exposures in the 18-45
energy bands. The source light curve shows the characteristic outburst shape
observed in this source.Comment: 4 pages, 3 figures (1 in CMYK color), accepted by Astronomy and
Astrophysics, INTEGRAL special issue, 200
INTEGRAL observations of the Be/X-ray binary EXO 2030+375 during outburst
We present a type-I outburst of the high-mass X-ray binary EXO 2030+375,
detected during INTEGRAL's Performance and Verification Phase in December 2002
(on-source time about 10e+06 seconds). In addition, six more outbursts have
been observed during INTEGRAL's Galactic Plane Scans. X-ray pulsations have
been detected with a pulse period of 41.691798+-0.000016 s. The X-ray
luminosity in the 5-300 keV energy range was 9.7*10e+36 erg/s, for a distance
of 7.1 kpc. Two unusual features were found in the light curve, with an initial
peak before the main outburst and another possible spike after the maximum.
RXTE observations confirm only the existence of the initial spike. Although the
initial peak appears to be a recurrent feature, the physical mechanisms
producing it and the possible second spike are unknown. Moreover, a four-day
delay between periastron passage and the peak of the outburst is observed. We
present for the first time a 5-300 keV broad-band spectrum of this source. It
can be modelled by the sum of a disk black body (kT_bb~8 keV) with either a
power law model with Gamma=2.04+-0.11 keV or a Comptonized component (spherical
geometry, kT_e=30 keV, tau=2.64, kT_W=1.5 keV).Comment: 10 pages, 11 figures, to be published in A&
Treatment of subclinical hyperthyroidism: Effect on body composition
Background: subclinical hyperthyroidism (SHT) is associated with harmful effects on cardiovascular system, bone metabolism and progression to clinical hyperthyroidism. Loss of weight is a common fact in patients with clinical hyperthyroidism and of particular relevance in elderly patients. Objective: to assess changes in body composition after radioiodine therapy for SHT due to toxic nodular goiter. Subjects and methods: prospective controlled cohort study. Patients with persistent SHT due to toxic nodular goiter were purposed to receive treatment with radioiodine (treatment group) or to delay treatment until the study was over (control group). All treated patients received 555 MBq of 131I. Body composition (lean mass, fat mass and bone mineral content) was determined by dual-energy X-ray absorptiometry (DEXA) at baseline and 12 months after. Results: twenty-nine patients were studied (age 69.5 ± 11.5; 75.9% women; BMI 27.1 ± 5.7 kg/m²; serum thyrotropin (TSH) 0.20 ± 0.21 µUI/mL; serum free thyroxine (T4) 1.01 ± 0.19 ng/dL), 17 belonging to the treatment group and 12 to the control group. Study groups were comparable, although there was a trend for the treatment group to have more fat mass. No longitudinal changes in body composition were noted in either group, except for a trend to gain fat mass. However, when individuals with age > 65 years were selected, only patients who received radioiodine therapy showed a significant increase in body weight (from 64.1 ± 10.0 to 66.9 ± 9.2 kg), BMI (from 27.3 ± 4.8 to 28.7 ± 4.5 kg/m²), fat mass (from 26.1 ± 8.5 to 27.8 ± 7.9 kg), lean mass (from 36.3 ± 0.4 to 37.4 ± 0.4 kg) and skeletal muscle mass index (SMI) (from 6.0 ± 0.6 to 6.3 ± 0.6 kg/m²). Conclusions: treatment of SHT has impact on body composition in subjects older than 65 years. Weight gain reflects increases in fat and, more interestingly, in lean mass
Probing stellar winds and accretion physics in high-mass X-ray binaries and ultra-luminous X-ray sources with LOFT
This is a White Paper in support of the mission concept of the Large
Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We
discuss the potential of LOFT for the study of high-mass X-ray binaries and
ultra-luminous X-ray sources. For a summary, we refer to the paper.Comment: White Paper in Support of the Mission Concept of the Large
Observatory for X-ray Timing. (v2 few typos corrected
Sarcoma European and Latin American Network (SELNET) Recommendations on Prioritization in Sarcoma Care During the COVID-19 Pandemic
175 Contribution of direct and bystander effects to therapeutic efficacy of alpha-RIT using 212Pb-labeled mAbs
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