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61.
Arianna D'Aulisa Alessandro Tugnoli Valerio Cozzani Gabriele Landucci Albrecht Michael Birk 《American Institute of Chemical Engineers》2014,60(12):4292-4305
Fire exposure of tanks used for the storage and transportation of liquefied gases under pressure may cause complex heat‐ and mass‐transfer phenomena that may contribute to compromise the integrity of the vessels in accident scenarios. Heat transfer through vessel lading results in the heat‐up of the internal fluid and the increase of vessel internal pressure. However, local temperature gradients in the liquid phase cause liquid stratification phenomena that result in a more rapid vaporization and pressure build‐up in the liquid phase. These fundamental phenomena were analyzed by a computational fluid dynamic model. The model was specifically focused on the early steps of vessel heat‐up, when liquid stratification plays a relevant role in determining the vessel internal pressure. A two‐dimensional transient simulation was set up using ANSYS FLUENT in order to predict the evolution of the liquid and vapor phases during the tank heat up. The model was validated against large scale experimental data available for liquefied petroleum gas vessels exposed to hydrocarbon fires, and was applied to case studies derived from recent accidental events in order to assess the expected time of pressure build‐up in different fire scenarios. © 2014 American Institute of Chemical Engineers AIChE J 60: 4292–4305, 2014 相似文献
62.
Environmental diversity and net primary productivity (NPP) are powerful indicators of local plant species richness (α-diversity). Remote sensing proxies of environmental diversity, such as spectral heterogeneity and NPP, are often used in modelling species richness variability, usually through regression analysis. As multicollinearity may affect analysis of species diversity, the interdependence of such proxies should be a major concern in their use. However, few attempts have been made to examine the interdependence between spectral heterogeneity and NPP proxies such as the Normalized Difference Vegetation Index (NDVI), in most cases using Ordinary Least Square (OLS) regression or Pearson correlations. We test the possible dependence of Landsat Enhanced Thematic Mapper (ETM+) local spectral heterogeneity versus NDVI using quantile regression and rejecting the main assumption of OLS regression, i.e. the symmetry of model residuals. A second-order polynomial function was fitted to the data and both OLS and quantile regression led to a humped-back relationship between spectral heterogeneity and biomass. Nonetheless while for most of the quantiles the humped-back curve was significant (with a negative and significant quadratic slope), for quantiles higher than 0.90, the parabola opened up until it reached an almost linear shape, showing that, at very low values of biomass, pixels may show high levels of local heterogeneity. Hence, patterns of spectral heterogeneity versus NDVI are possible when considering maximum potential spectral variability. We show that the investigation of all possible subsets within a scatter plot may lead to identification of patterns that remain hidden in OLS regression. 相似文献
63.
We present a simple, compact, and versatile experimental setup working in the heterodyne detection mode with modulation of the reference beam. The system is implemented with a collection optics based on a unimodal optical fiber coupler. This choice allows the heterodyne to be used in a wide range of scattering angles, even for very small ones, without losing the optical beating. The apparatus can be successfully used to study translational diffusive dynamics of dispersed particles at scattering angles smaller than 5° and it is suitable for exploring slow relaxation processes in sub-Hertz frequency domain, for example, in glass-forming systems. It is also possible to measure the electrophoretic mobility by applying an electric field into a charged particles solution. 相似文献
64.
Dr. Andrea Casiraghi Dr. Francesca Longhena Dr. Valentina Straniero Dr. Gaia Faustini Dr. Amy H. Newman Prof. Arianna Bellucci Prof. Ermanno Valoti 《ChemMedChem》2020,15(14):1330-1337
We previously described synapsin III (Syn III) as a synaptic phosphoprotein that controls dopamine release in cooperation with α-synuclein (aSyn). Moreover, we found that in Parkinson's disease (PD), Syn III also participates in aSyn aggregation and toxicity. Our recent observations point to threo-methylphenidate (MPH), a monoamine re-uptake inhibitor that efficiently counteracts the freezing-gait characteristic of advanced PD, as a ligand for Syn III. We have designed and synthesised two different fluorescently labelled MPH derivatives, one with Rhodamine Red (RHOD) and one with 5-carboxytetramethylrhodamine (TAMRA), to be used for assessing MPH binding to Syn III by FRET. TAMRA-MPH exhibited the ideal characteristics to be used as a FRET acceptor, as it was able to enter into the SK-N-SH cells and could interact specifically with human green fluorescent protein (GFP)-tagged Syn III but not with GFP alone. Moreover, the uptake of TAMRA-MPH and co-localization with Syn III was also observed in primary mesencephalic neurons. These findings support that MPH is a Syn III ligand and that TAMRA-conjugated drug molecules might be valuable tools to study drug-ligand interactions by FRET or to detect Syn III in cytological and histological samples. 相似文献
65.
This paper describes and discusses experimental results on the absorption of sulphur dioxide in electrified water sprays, either when the polluted gas is treated as is or when the gas is exposed to a corona source to ionize the sulphur dioxide. The experiments revealed that an electrified spray with a charge-to-mass ratio of 50 μC · kg−1 enabled the absorption rate of droplets to double, regardless of their polarities. Corona charging gave rise to an increase in the SO2 depletion rate over the scrubber wall, while negligible effects appeared on the actual droplets absorption rate. These findings suggested that faster absorption rates mostly, though not uniquely, depend on the modifications on the morphological and interfacial properties of the sprayed droplets induced by the free electric charge imposed on their surface. Conversely, the absorption rates were negligibly affected by the electrical interactions between droplets (either charged or uncharged) and the sulphur dioxide ions/radicals originating from the corona source. 相似文献
66.
67.
Gianni Ciofani Vittoria Raffa Arianna Menciassi Alfred Cuschieri 《Nanoscale research letters》2009,4(2):113-121
Boron neutron capture therapy (BNCT) is increasingly being used in the treatment of several aggressive cancers, including
cerebral glioblastoma multiforme. The main requirement for this therapy is selective targeting of tumor cells by sufficient
quantities of 10B atoms required for their capture/irradiation with low-energy thermal neutrons. The low content of boron targeting species
in glioblastoma multiforme accounts for the difficulty in selective targeting of this very malignant cerebral tumor by this
radiation modality. In the present study, we have used for the first time boron nitride nanotubes as carriers of boron atoms
to overcome this problem and enhance the selective targeting and ablative efficacy of BNCT for these tumors. Following their
dispersion in aqueous solution by noncovalent coating with biocompatible poly-l-lysine solutions, boron nitride nanotubes were functionalized with a fluorescent probe (quantum dots) to enable their tracking
and with folic acid as selective tumor targeting ligand. Initial in vitro studies have confirmed substantive and selective
uptake of these nanovectors by glioblastoma multiforme cells, an observation which confirms their potential clinical application
for BNCT therapy for these malignant cerebral tumors. 相似文献
68.
Arianna Alfieri Leo Kroon Steef van de Velde 《Journal of Intelligent Manufacturing》2007,18(2):223-232
In complex logistic systems, such as transportation systems, dealing with personnel scheduling is a non-trivial task. Duties
have to be created and assigned to workers in a way to optimize a certain objective function. In this paper, in particular,
we consider the case of scheduling train drivers on a railway subnetwork. Train driver scheduling involves the construction
of feasible duties from a set of trips to be carried out by a number of train drivers. Each duty consists of a sequence of
trips to be carried out by a single train driver on a single day. The duties should be such that: each trip is covered by
at least one duty, each duty satisfies feasibility constraints, additional constraints involving the complete schedule are
satisfied, one or several objectives are met. In this paper we focus on minimizing the number of duties and on maximizing
the robustness of the obtained schedule for outside disruptions. We present an implicit column generation solution approach.
We describe a heuristic procedure to find an initial feasible solution together with a heuristic branch-and-price algorithm
based on a dynamic programming algorithm for the pricing-out of columns. We tested our approach on the timetable of the Intercity
train series 500, 700, 1600 and 1700 of NS Reizigers, the largest Dutch operator of passengers trains. 相似文献
69.
Calculation of the scattering pattern from aggregates of spheres through the T-matrix approach yields high-precision results but at a high-computational cost, especially when the aggregate concerned is large or is composed of large-size spheres. With reference to a specific but representative aggregate, we discuss how and to what extent the computational effort can be reduced but still preserve the qualitative features of the signature of the aggregate concerned. 相似文献
70.
The paper presents the development of segmented artificial crawlers endowed with passive hook-shaped frictional microstructures.
The goal is to find design rules for fabricating biomimetic, adaptable and mobile machines mimicking segmented animals with
hydrostatic skeleton, and intended to move effectively along unstructured substrates.
The paper describes the mechanical model, the design and the fabrication of a SMA-actuated segmented microrobot, whose locomotion
is inspired by the peristaltic motion of Annelids, and in particular of earthworms (Lumbricus Terrestris). Experimental locomotion performance are compared with theoretical performance predicted by a purposely developed friction
model -taking into account design parameters such as number of segments, body mass, special friction enhancement appendixes—and
with locomotion performance of real earthworms as presented in literature.
Experiments indicate that the maximum speed of the crawler prototype is 2.5 mm/s, and that 3-segment crawlers have almost
the same velocity as earthworms having the same weight (and about 330% their length), whereas 4-segment crawlers have the
same velocity, expressed as body lengths/s, as earthworms with the same mass (and about 270% their length).
Arianna Menciassi (MS, 1995; PhD, 1999) joined the CRIM Lab of the Scuola Superiore Sant’Anna (Pisa, Italy) as a Ph.D. student in Bioengineering
with a research program on the micromanipulation of mechanical and biological micro-objects. The main results of the activity
on micromanipulation were presented at the IEEE International Conference on Robotics & Automation (May 2001, Seoul) in a paper
titled “Force Feedback-based Microinstrument for Measuring Tissue Properties and Pulse in Microsurgery”, which won the “ICRA2001
Best Manipulation Paper Award”. In the year 2000, she was offered a position of Assistant Professor in Biomedical Robotics
at the Scuola Superiore Sant’Anna and in June 2006 she obtained a promotion to Associate Professor. Her main research interests
are in the field of biomedical microrobotics, biomimetics, microfabrication technologies, micromechatronics and microsystem
technologies. She is working on several European projects and international projects for the development of minimally invasive
instrumentation for medical applications and for the exploitation of micro- and nano-technologies in the medical field.
Samuele Gorini received his Laurea Degree in Mechanical Engineering (with honors) from the University of Pisa, Italy, in 2001. In 2005 he
obtained the Ph.D. in Microsystem Engineering with a thesis on locomotion methods and systems for miniaturised endoscopic
devices. Since 2000, he has been working at the CRIM Lab of the Scuola Superiore Sant’Anna in Pisa, Italy. His research interests
are in the field of biomedical robotics with a special focus on actuation technologies. Starting from the year 2004 he has
been president of Era Endoscopy S.r.l., a start-up company of Scuola Superiore Sant’Anna developing novel devices for endoscopy.
Dino Accoto (MS 1998, PhD 2002) is Assistant Professor of Biomedical Engineering at Scuola Sant’Anna (Pisa, Italy). He received the Laurea
degree in Mechanical Engineering from the University of Pisa (cum laude) in 1998, the diploma in Engineering from the Scuola
Sant’Anna (cum laude) in 1999 and the PhD degree from the Scuola Sant’Anna in 2002. From October 2001 to September 2002 he
has been visiting scholar at the RPL-Lab, Stanford University (Ca, USA). Since 2004 he cooperates with the Biomedical Robotics
& EMC Lab at Campus Bio-Medico University in Rome. His main research field is the modelling and development of small electromechanical
systems, with a special attention to multi-physics and multi-domain approaches. The research, often inspired by the analysis
of natural mechanisms, has been mainly applied to hybridizing microtechnologies, including microfluidics, and robotics. He
has co-authored more than 30 papers, appeared in international journals and conference proceedings.
Paolo Dario received his Dr. Eng. Degree in Mechanical Engineering from the University of Pisa, Italy, in 1977. He is currently a Professor
of Biomedical Robotics at the Scuola Superiore Sant’Anna in Pisa.. He also teaches courses at the School of Engineering of
the University of Pisa and at the Campus Biomedico University in Rome. He has been Visiting Professor at Brown University,
Providence, RI, USA, at the Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland, at Waseda University,
Tokyo, Japan, at the College de France, Paris, and at the Ecole Normale Superieure de Cachan, France. He was the founder of
the ARTS (Advanced Robotics Technologies and Systems) Laboratory and is currently the Co-ordinator of the CRIM (Center for
the Research in Microengineering) Laboratory of the Scuola Superiore Sant’Anna, where he supervises a team of about 70 researchers
and Ph.D. students. His main research interests are in the fields of medical robotics, bio-robotics, mechatronics and micro/nanoengineering,
and specifically in sensors and actuators for the above applications, and in robotics for rehabilitation. He is the coordinator
of many national and European projects, the editor of two books on the subject of robotics, and the author of more than 200
scientific papers (75 on ISI journals). He is Editor-in-Chief, Associate Editor and member of the Editorial Board of many
international journals. Prof. Dario has served as President of the IEEE Robotics and Automation Society in the years 2002–2003.
He has been the General Chair of the IEEE RAS-EMBS BioRob’06 Conference and he is the General Co-Chair of ICRA 2007 Conference.
Prof. Dario is an IEEE Fellow, a Fellow of the European Society on Medical and Biological Engineering, and a recipient of
many honors and awards, such as the Joseph Engelberger Award. He is also a member of the Board of the International Foundation
of Robotics Research (IFRR). 相似文献