Biomass Gasification and Tar Reforming in a Two-stage Reactor

Abstract Gasification is recognized as one of the most promising technologies to convert low quality fuels into more valuable ones. The principal problem related with the use of biomass in gasification processes is the high amount of tar released during the pyrolysis step. It is thus necessary to recover the tar and to transform it in lighter combustible gas species such as CH4, CO and H2 by means of catalytic processes. In this work the gasification of olive husk is performed in order to produce a high quality syngas, composed principally by carbon monoxide and hydrogen, using an innovative laboratory scale two-stage reactor. The first stage is used for gasification and the second for catalytic reforming. It is thus possible to recover the tar energy converting it into CO and H2. Ce-promoted bimetallic Ni-Co catalyst was tested and compared with Ni catalyst, both supported on γ-Al2O3

Developmental responses to early-life adversity: Evolutionary and mechanistic perspectives

Adverse ecological and social conditions during early life are known to influence development, with rippling effects that may explain variation in adult health and fitness. The adaptive function of such developmental plasticity, however, remains relatively untested in long-lived animals, resulting in much debate over which evolutionary models are most applicable. Furthermore, despite the promise of clinical interventions that might alleviate the health consequences of early-life adversity, research on the proximate mechanisms governing phenotypic responses to adversity have been largely limited to studies on glucocorticoids. Here, we synthesize the current state of research on developmental plasticity, discussing both ultimate and proximate mechanisms. First, we evaluate the utility of adaptive models proposed to explain developmental responses to early-life adversity, particularly for long-lived mammals such as humans. In doing so, we highlight how parent-offspring conflict complicates our understanding of whether mothers or offspring benefit from these responses. Second, we discuss the role of glucocorticoids and a second physiological system-the gut microbiome-that has emerged as an additional, clinically relevant mechanism by which early-life adversity can influence development. Finally, we suggest ways in which nonhuman primates can serve as models to study the effects of early-life adversity, both from evolutionary and clinical perspectives.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152003/1/evan21791_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152003/2/evan21791.pd

Evolution of vertebral numbers in primates, with a focus on hominoids and the last common ancestor of hominins and panins

The primate vertebral column has been extensively studied, with a particular focus on hominoid primates and the last common ancestor of humans and chimpanzees. The number of vertebrae in hominoids—up to and including the last common ancestor of humans and chimpanzees—is subject to considerable debate. However, few formal ancestral state reconstructions exist, and none include a broad sample of primates or account for the correlated evolution of the vertebral column. Here, we conduct an ancestral state reconstruction using a model of evolution that accounts for both homeotic (changes of one type of vertebra to another) and meristic (addition or loss of a vertebra) changes. Our results suggest that ancestral primates were characterized by 29 precaudal vertebrae, with the most common formula being seven cervical, 13 thoracic, six lumbar, and three sacral vertebrae. Extant hominoids evolved tail loss and a reduced lumbar column via sacralization (homeotic transition at the last lumbar vertebra). Our results also indicate that the ancestral hylobatid had seven cervical, 13 thoracic, five lumbar, and four sacral vertebrae, and the ancestral hominid had seven cervical, 13 thoracic, four lumbar, and five sacral vertebrae. The last common ancestor of humans and chimpanzees likely either retained this ancestral hominid formula or was characterized by an additional sacral vertebra, possibly acquired through a homeotic shift at the sacrococcygeal border. Our results support the ‘short-back’ model of hominin vertebral evolution, which postulates that hominins evolved from an ancestor with an African ape–like numerical composition of the vertebral column

A symbolic treatment of Riordan arrays

We approach Riordan arrays and their generalizations via umbral symbolic methods. This new approach allows us to derive fundamental aspects of the theory of Riordan arrays as immediate consequences of the umbral version of the classical Abel's identity for polynomials. In particular, we obtain a novel non-recursive formula for Riordan arrays and derive, from this new formula, some known recurrences and a new recurrence relation for Riordan arrays. © 2013 Elsevier Inc. All rights reserved

On One-Parameter Catalan Arrays

We present a parametric family of Riordan arrays, which are obtained by multiplying any Riordan array with a generalized Pascal array. In particular we focus on some interesting properties of one-parameter Catalan triangles. -We obtain several combinatorial identities that involve two special Catalan matrices, the Chebyshev polynomials of the second kind, some periodic sequences, and the Fibonacci numbers

Combinatorics of a generalized Narayana identity

The Narayana identity is a well-known formula that expresses the classical Catalan numbers as sums of the ordinary Narayana numbers. In this paper we generalize the Narayana identity to a family of Riordan arrays including the array of ballot numbers, the classical Catalan triangle and several generalized Catalan triangles recently studied. A combinatorial description based on non-crossing partitions is given for this identity, for the column-recursive rule, and for the Sheffer sequence associated with any array of the family

The Officina Pigmentaria in Pompei: pigments and cosmetics

According to the “Giornale di Scavo” of the Archaeological Superintendance of Pompeii, the first excavation in the Regio I, Insula 9 (I,9,9) took place in 1952. In a building of seven rooms there was a stair in opus incertum with the floors in cocciopesto. Near the skeletons of four individuals, about 150 globular bowls, fritilla and ollae were found. They were assigned the numbers between 9389 and 9700. Due to the high number of containers and to the presence of material inside, they have a high importance for the history of materials in Pompeii and in the Roman world. In particular, they should be important for the reconstruction of the painting history and techniques of this period. An investigation with different techniques for the identification of the contents composition and subsequently for the understanding of the materials present was then undertaken. For the study two molecular techniques were used, that is FT-IR spectroscopy and Raman microscopy. The first is able to supply information about the general composition of the compound present in the samples at least in the concentration of about 1 %. The second techniques can inform on the composition of single grains as small as 1-2 micrometers. Therefore, the results of the two techniques must help each other to understand what the analyzed powder is. The analyses of all the bowl contents are summarized in a long table, of which we report only a section. By comparing the results obtained some considerations come to light. Many containers have quartz and calcite, that are the main component of plasters, to which feldspars and pyrite can be added. At the same time diopside can come from eruptive rocks or from silicate materials heated to high temperature. Aragonite is present, sometimes at high concentration, in many pigments, and its presence can be due to natural provenance from white minerals, but more probably can be due to the grinding of shells. This is an important testimony of what is identified in white lines on colored background in Roman wall paintings. The blue pigment is always based on Egyptian blue, at the time of Pompeii destruction coming from Puteoli or Liternum. Green can be obtained by mixing a yellow and a blue, and this is generally found on wall paintings; more frequently green is ascertained to be a mixture of green earth and some Egyptian blue. Malachite and azurite are encountered as degradation products of copper and brass containers. Other rare occurrence are cuprite, also coming from alterations of a metal, and litharge, from alteration of cerussite or lead objects. The case of cerussite or hydrocerussite is different. It can be identified in many recipients, but it is not a pigment for wall paintings. Since it is known from Pliny and other authors that it was used as a fard, this can be a proof of the production and filling also of cosmetics containers in I, 9, 9