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Spouting behaviour of binary mixtures in square-based spouted beds

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Particuology 2019年第2期17卷 193-201页

作者： cristina Moliner Filippo Marchelli Massimo Curti Barbara Bosio Giorgio Rovero Elisabetta Arato Department of Civil Chemical and Environmental Engineering (DICCA) University of Genova (UNIGE) Genova Italy Faculty of Science and Technology Free University of Bolzano (UNIBZ) Bolzano Italy Department of Applied Science and Technology (DISAT) Polytechnic University of Turin (POLITO) Turin Italy

From experime nts, the influe nee of the physical characteristics of different bin ary mixtures of solids on the spouting regime of a pyramidal square-based spouted bed reactor is assessed. The applied methodology permits a more precise evaluation of the effects of the tested variables (diameter, density, sphericity) on the response variables (minimum air flows at which spouting begins and at which to maintain spouting con ditions). The associated pressure drops along the bed of particles a nd the height of the formed fountai n are analysed in each case. During the initial stages of fluidisation, binary mixtures containing different density ratios show dead zones. Segregation becomes more evident at large-size and high-density ratios. The lack of sphericity was found to be the main reason leading to blocking, channelling, and start-up problems when system failures occur. Nevertheless, the extent of segregation in all cases decreases with increasing the spouting velocity. In addition, a computational fluid dynamic model based on the discrete element method, previously validated for a single solid bed, is proposed as a tool to predict and evaluate potential segregation phenomena in binary mixtures. This model reproduced with high accuracy the encountered segregation phenomena. Its use may help define the technical limts inherent in the pyramidal spouted bed reactor.

关键词： Spouted bed reactor Segregation Computational fluid dynamics

Benthic diatom community response to metal contamination from an abandoned Cu mine:Case study of the Gromolo Torrent(Italy)

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Journal of Environmental Sciences 2019年第1期31卷 233-246页

作者： Raffaella Tolotti Sirio Consani cristina Carbone Greta Vagge Marco Capello Laura Cutroneo Department of Earth Environment and Life Sciences University of Genoa

Environmental contamination has become a global problem of increasing intensity due to the exponential growth of industrialization. One main debated issue is the metal contamination of rivers receiving Acid Mine Drainage(AMD) from active/abandoned mines. In order to assess the quality of lotic systems, diatoms are commonly used, as their assemblage modifies on the basis of changes in environmental parameters. Benthic diatom changes were analyzed along the metal-impacted Gromolo Torrent(Liguria, NW Italy) with the aim of understanding the effects of input from the abandoned Libiola Cu mine. The results support the hypothesis that metals from AMD lead to massive changes in diatoms, resulting in low biological diversity and in a shift of dominance, passing from the genera Cymbella and Cocconeis to more tolerant and opportunistic species, such as Achnanthidium minutissimum and Fragilaria rumpens. The high concentrations of labile metals, measured through Diffusion Gradients in Thin-films(DGT) immediately downstream of the two AMD inputs in the torrent, corresponded to a sudden decrease in the presence of diatoms, indicating the possible reaching of acute toxic levels. In particular,A. minutissimum dominated the mining area and was positively correlated with Cu and Zn;whereas F. rumpens bloomed downstream of this area, where the metal content was diluted,and was positively correlated with As and Pb. Finally, an important abundance of Nitzschia palea and teratological forms of A. minutissimum and F. rumpens were observed downstream from the mine, indicating that metals may have an important impact on diatoms up to the torrent mouth.

关键词： Benthic diatom community Biomarkers Metal contamination Diatom teratologies Acid Mine Drainage Libiola mine (Liguria,NW Italy)

Aspects of forest restoration and hydrology:the hydrological function of litter

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Journal of Forestry Research 2022年第2期33卷 543-552页

作者： Luara Castilho Pereira Leonardo Balbinot Marcelle Teodoro Lima Julieta Bramorski Kelly cristina Tonello Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of São Carlos(UFSCar)SorocabaSão PauloBrazil Hydrology in Forest Ecosystems Lab.(Hidrolef) Department of Environmental SciencesFederal University of Amapá(UNIFAP)MacapáAmapáBrazil

Although forests play important roles in the hydrological cycle,there is little information that relates the water retention capacity of litter in areas under passive restoration,especially in Cerrado *** study relates litter levels to water holding capacity and effective water retention among forest fragments under different passive restoration stages:46,11,and 8 years to better understand litter hydrological functions in the *** retention capacity and effective water retention capacity of litters(unstructured materials,branches and leaves)in the field were monitored on a monthly *** litter accumulation at 46 years was significantly higher than that of the other succession *** litter mass was significantly higher than that of leaves and *** 46-year stage had the highest water holding capacity in the leaf fraction,followed by unstructured material and *** the water holding capacity was lower in the oldest resto-ration,this site showed the highest efficiency under field *** process was quickly reestablished,as the 11-year restoration showed results closer to that for the 46-year stage in comparison to the area at 8 ***,passive restoration plays a key role in soil water mainte-nance due to the influence of litter in Cerrado *** and the imminent need of restoring degraded sites,highlight the need for further studies focused on bet-ter understanding of the process of forest restoration and its temporal effect on soil water recovery dynamics.

关键词： Forest hydrology Litter interception Stemflow Cerrado Águas Perenes Forest Water holding capacity

Alpha-synuclein as a biomarker in Parkinson's disease: focus on neural derived extracelluar vesicles

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Neural Regeneration Research 2022年第7期17卷 1503-1504页

作者： cristina Agliardi Franca R.Guerini Mario Meloni Mario Clerici IRCCS Fondazione Don Carlo Gnocchi MilanItaly Department of Pathophysiology and Transplantation University of MilanMilanItaly

The prevalence of Parkinson’s disease(PD)is rapidly increasing,and more than 12 million people are expected to suffer from PD by *** is a highly invalidating neurodegenerative condition that arises from the progressive degeneration of dopaminergic neurons in the substantia nigra pars *** main cause for such degeneration is the formation of cytoplasmic inclusions known as Lewy bodies.

关键词： degeneration Alpha prevalence

Oxidative dehydrogenation of propane under steady-state and transient regimes over alumina-supported catalysts prepared from mixed V_2W_4O_(19)^(4-) hexametalate precursors

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Journal of Natural Gas Chemistry 2010年第2期19卷 123-133页

作者： Sébastien Paul Elise Berrier Marcia cristina Kaezer Frana Jean-Guillaume Eon Univ Lille Nord de France F-59000 LilleFrance ECLille UCCSF-59650 Villeneuve d'AscqFrance CNRS UMR 8181F-59650 Villeneuve d'AscqFrance USTL UCCSF-59650 Villeneuve d'AscqFrance Instituto de Quimíca Universidade Federal do Rio de Janeiro-Cidade UniversitáriaIlha do Fundo21945-970 Rio de JaneiroBrazil

An integrated approach combining the development of an innovative catalyst and the research of a set of adequate operating conditions for the propane oxidative dehydrogenation （ODH） is *** experimental set-up,specially designed for steady-state and transient studies is *** preparation method,the characterization and the performances in steady-state and transient regimes of catalysts based on V2W4O194-Lindqvist isopolyanion used as a precursor and supported on alumina are *** influence of the preparation method of the catalyst and the role of water in the feed gas are more particularly discussed.

关键词： propane oxidative dehydrogenation (ODH) transient regime pulsed reactor Lindqvist isopolyanion in-situ Raman

Approximation of the Long-Time Dynamics of the Dynamical System Generated by the Ginzburg-Landau Equation

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Communications in Mathematical Research 2023年第4期39卷 501-522页

作者： cristina Tone Florentina Tone Department of Mathematics University of LouisvlleLouisilleKY 40292USA Department Mathematics and Statistics University of West FloridaPensacolaFL 32514USA.

In this article we consider the(complex)Ginzburg-Landau equation,we discretize in time using the implicit Euler scheme,and with the aid of the discrete Gronwall lemma and of the discrete uniform Gronwall lemma we prove that the global attractors generated by the numerical scheme converge to the global attractor of the continuous system as the time-step approaches zero.

关键词： Ginzburg-Landau equation implicit Euler scheme long-time stability at-tractors

Unveiling sinus venosus atrial septal defect and partial anomalous pulmonary venous return in an elderly patient

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Journal of Geriatric Cardiology 2024年第4期21卷 462-464页

作者： cristina M Font Anamarys Blanco Fernandez Dinesh Kadariya Department of Medicine Division of CardiologyUniversity of Florida College of MedicineJacksonvilleFloridaUSA

Sinus venosus defect(SVD) accounts for 4%–11% of all atrial septal defects(ASD) and may present with dyspnea, heart failure(HF), palpitations, or angina.^[1] The malformation typically involves an interatrial communication due to a deficiency in the common wall connecting the right pulmonary veins and the superior vena cava(SVC) and often accompanies anomalous pulmonary venous connection of some or all of the pulmonary veins.

关键词： atrial septal venous

Anesthetic dilemmas in an achondroplastic patient undergoing elective cesarean section

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Journal of Biomedical Research 2024年第5期38卷 512-515页

作者： Aaron Brown Hong Liu cristina Chandler Department of Anesthesiology and Pain Medicine University of California Davis HealthSacramentoCA 95817USA

Achondroplasia is a genetic condition characterized by skeletal dysplasia that results in characteristic craniofacial and spinal *** is the most common form of short-limbed skeletal dysplasia.A morbidly obese pregnant patient warrants specific anatomical and physiological considerations,such as a difficult airway with potential hypoxia,full stomach precautions,and a reduced functional residual *** increases the risks of maternal and fetal *** neuraxial techniques are generally preferred for cesarean sections,there is no consensus among patients with *** aimed to discuss the anesthetic challenges in an achondroplastic patient and report our regional anesthesia approach for an elective cesarean section.

关键词： achondroplasia skeletal dysplasia combined spinal-epidural anesthesia cesarean delivery

Evolution of deceit by worthless donations in a nuptial gift-giving spider

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Current Zoology 2014年第1期60卷 43-51页

作者： Paolo Giovanni GHISLANDI Mafia J. ALBO cristina TUNI Trine BILDE Department of Bioscience Aarhus University 8000 Aarhus C Denmark Laboratorio de Etologia Ecologia y Evoluci6n IIBCE Uruguay

Males of the nursery web spider Pisaura mirabil usually offer an insect prey wrapped in white silk as a nuptial gift to facilitate copulation. Males exploit female foraging preferences in a sexual context as females feed on the gift during copula- tion. It is possible for males to copulate without a gift, however strong female preference for the gift leads to dramatically higher mating success for gift-giving males. Females are polyandrous, and gift-giving males achieve higher mating success, longer copulations, and increased sperm transfer that confer advantages in sperm competition. Intriguingly, field studies show that ap- proximately one third of males carry a worthless gift consisting of dry and empty insect exoskeletons or plant fragments wrapped in white silk. Silk wrapping disguises gift content and females are able to disclose gift content only after accepting and feeding on the gift, meanwhile males succeed in transferring sperm. The evolution of deceit by worthless gift donation may be favoured by strong intra-sexual competition and costs of gift-construction including prey capture, lost foraging opportunities and investment in silk wrapping. Females that receive empty worthless gifts terminate copulation sooner, which reduces sperm transfer and likely disadvantages males in sperm competition. The gift-giving trait may thus become a target of sexually antagonistic co-evolution, where deceit by worthless gifts leads to female resistance to the trait. We discuss factors such as female mating rate and intensity of sperm competition that may shape the evolution of male deception, and how ecological factors may influence the evolution and maintenance of worthless gifts as an evolutionarily stable alternative mating strategy by frequency dependent selection

关键词： Sexual selection Sexual conflict Nuptial gift Worthless gift Polyandry Polymorphic trait Sperm competition