1,481 research outputs found
Development of a high temperature battery final report
Development of battery with lithium-magnesium alloy anode, molten cuprous chloride cathode, and zeolite separator cells and cupric oxide cathode and porous glass separator cell
On the habitat use of the Neotropical whip spider Charinus asturius (Arachnida: Amblypygi)
The non-random occupation of habitats is termed habitat selection. Some species of whip spiders select trees with burrows at their base, while others use substrates such as rocks. Here, we investigated the habitat use by Charinus asturius Pinto-da-Rocha, Machado & Weygoldt, 2002, an endemic species of Ilhabela Island in Brazil. We found that C. asturius is more likely to be found under rocks that cover larger areas of substrate. Our results also suggest the existence of territorialism in C. asturius and show that C. asturius adults may be found again on the same rock a week later. Additionally, our data show that C. asturius is present in a greater area of Ilhabela than previously documented.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2014/19191-3, 2015/01518-9]Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) [133214/2015-0]Univ Sao Paulo, Escola Artes Ciencias & Humanidades, Lab Ecol Sensorial & Comportamento Artropodes, Rua Arlindo Bettio 1000, BR-03828000 Sao Paulo, SP, BrazilUniv Sao Paulo, Inst Biociencias, Programa Pos Grad Zool, Rua Matao 321,Travessa 14, BR-05508900 Sao Paulo, BrazilUniv Sao Paulo, Inst Psicol, Dept Psicol Expt, Ave Prof Mello de Morais,1721 Butanta, BR-05508030 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Programa Pos Grad Ecol & Evolucao, Rua Prof Artur Riedel 275, BR-09972270 Diadema, BrazilUniv Fed Sao Paulo, Programa Pos Grad Ecol & Evolucao, Rua Prof Artur Riedel 275, BR-09972270 Diadema, BrazilFAPESP: [2014/19191-3, 2015/01518-9]CNPq: [133214/2015-0]Web of Scienc
Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico
Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country
is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were
analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related
to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in
concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along
the monitoring period. No anthropogenic pollution from Volatile Organic Compounds (VOCs) was observed. An
overview of the soil radon behaviour as a function of the volcanic activity in the period 1994-2002 is also discussed
Weighted norm inequalities for polynomial expansions associated to some measures with mass points
Fourier series in orthogonal polynomials with respect to a measure on
are studied when is a linear combination of a generalized Jacobi
weight and finitely many Dirac deltas in . We prove some weighted norm
inequalities for the partial sum operators , their maximal operator
and the commutator , where denotes the operator of pointwise
multiplication by b \in \BMO. We also prove some norm inequalities for
when is a sum of a Laguerre weight on and a positive mass on
The inner flow geometry in MAXI J1820+070 during hard and hard-intermediate states
[Abridged] Context: We present a systematic X-ray spectral-timing study of
the recently discovered, exceptionally bright black hole X-ray binary system
MAXI J1820+070. Our analysis focuses on the first part of the 2018 outburst,
covering the rise throughout the hard state, the bright hard and
hard-intermediate states, and the transition to the soft-intermediate state.
Aims: We address the issue of constraining the geometry of the innermost
accretion flow and its evolution throughout an outburst. Methods: We employed
two independent X-ray spectral-timing methods applied to the NICER data of MAXI
J1820+070. We first identified and tracked the evolution of a characteristic
frequency of soft X-ray reverberation lags. Then, we studied the spectral
evolution of the quasi-thermal component responsible for the observed thermal
reverberation lags. Results: The frequency of thermal reverberation lags
steadily increases throughout most of the outburst, implying that the relative
distance between the X-ray source and the disc decreases as the source softens.
However, near transition this evolution breaks, showing a sudden increase
(decrease) of lag amplitude (frequency). The evolution of the quasi-thermal
component in high-frequency covariance spectra is consistent with a steady
decrease of the inner radius of the disc as the source softens. Conclusions:
The behaviour of thermal reverberation lags near transition might be related to
relativistic plasma ejections detected at radio wavelengths later in the
outburst, possibly representing the precursor to such events. Throughout most
of the hard and hard-intermediate states the disc is consistent with being
truncated (with an inner radius ), reaching close
to the innermost stable circular orbit only near transition.Comment: Submitted for publication in Astronomy & Astrophysic
Inherently safer design and optimization of intensified separation processes for furfural production
Inherently Safer Design and Optimization of Intensified Separation Processes for Furfural Production
Currently
furfural production has been the subject of increased
interest because it is a biobased chemical able to compete with fossil-based
chemicals. Furfural is characterized by flammability, explosion, and
toxicity properties. Improper handling and process design can lead
to catastrophic accidents. Hence it is of most importance to use inherent
safety concepts during the design stage. This work is the first to
present several new downstream separation processes for furfural purification,
which are designed using an optimization approach that simultaneously
considers safety criteria in addition to the total annual cost and
the eco-indicator 99. The proposed schemes include thermally coupled
configuration, thermodynamic equivalent configuration, dividing-wall
column, and a heat integrated configuration. These are compared with
the traditional separation process of furfural known as the Quaker
Oats Process. The results show that because of a large amount of water
present in the feed, similar values are obtained for total annual
cost and eco-indicator 99 in all cases. Moreover, the topology of
the processes has an important role in the safety criteria. The thermodynamic
equivalent configuration resulted as the safest alternative with a
40% reduction of the inherent risk with respect to the Quaker Oats
Process, and thus it is the safest option to purify furfural
Spontaneous magnetization of aluminum nanowires deposited on the NaCl(100) surface
We investigate electronic structures of Al quantum wires, both unsupported
and supported on the (100) NaCl surface, using the density-functional theory.
We confirm that unsupported nanowires, constrained to be linear, show
magnetization when elongated beyond the equilibrium length. Allowing ions to
relax, the wires deform to zig-zag structures with lower magnetization but no
dimerization occurs. When an Al wire is deposited on the NaCl surface, a
zig-zag geometry emerges again. The magnetization changes moderately from that
for the corresponding unsupported wire. We analyse the findings using electron
band structures and simple model wires.Comment: submitted to PHys. Rev.
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