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Sorbents with high efficiency for CO2 capture based on amines-supported carbon for biogas upgrading

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Journal of Environmental Sciences 2016年第10期28卷 138-150页

作者： Lidia Pino cristina Italiano Antonio Vita Concetto Fabiano Vincenzo Recupero CNR Institute of Aduanced Technology for Energy "Nicola Giordano" Via S. Lucia 5 98126 Messina Italy

Sorbents for CO2 capture have been prepared by wet impregnation of a commercial active carbon （Ketjen-black, Akzo Nobel） with two CO2-philic compounds, polyethylenimine （PEI） and tetraethylenepentamine （TEPA）, respectively. The effects of amine amount （from 10 to 70 wt.%）, CO2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N2 adsorption-desorption, scanning electron microscopy and energy dispersive X-ray （SEM/EDX）. A promising CO2 sorption capacity of 6.90 mmo1/gsorbent has been obtained with 70 wt.% of supported TEPA at 70℃ under a stream containing 80 vol% of CO2. Sorption tests, carried out with simulated biogas compositions （CH4/CO2 mixtures）, have revealed an appreciable CO2 separation selectivity; stable performance was maintained for 20 adsorption-desorption cycles.

关键词： CO2 capturePEI-TEPA based sorbentsAmine efficiencyBiogasSeparation selectivity

Insights on ZEB1-AS1:emerging role from cancer to neurodegeneration

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Neural Regeneration Research 2024年第6期19卷 1187-1188页

作者： Stephana Carelli Federica Rey Erika Maghraby cristina Cereda Pediatric Research Center“Romeo ed Enrica Invernizzi” Department of Biomedical and Clinical SciencesUniversity of MilanMilanItaly Center of Functional Genomics and Rare Diseases Department of PediatricsBuzzi Children’s HospitalMilanItaly Department of Biology and Biotechnology“L.Spallanzani” University of PaviaPaviaItaly

Implications for lncRNAs in the central nervous system:Transcriptional dysregulation is a key contributor to the pathogenesis of a wide range of diseases and long non-coding RNAs(lncRNAs)are highly expressed in the nervous ***,amongst the over 50,000 lncRNAs expressed in the human genome,more than 40%are specifically expressed in the brain where their roles in brain development,neuron functions,maintenance.

关键词： ZEB1 diseases pathogenesis

Extracts from Marine Macroalgae and Opuntia ficus-indica Cladodes Enhance Halotolerance and Enzymatic Potential of Diazotrophic Rhizobacteria and Their Impact on Wheat Germination Under Salt Stress

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Pedosphere 2018年第2期28卷 241-254页

作者： Abdelwahab RAI Ameur CHERIF cristina CRUZ Elhafid NABTI Département de Microbiologie Faculté des Sciences de la Nature et de la Vie Université Ferhat Abbas Sdtif-1 19000 (Algdrie) Universitg de Béjaia FSNV Laboratoire de Maitrise des Energies Renouvelables (LMER) Equipe de Biomasse et Environnement Targa Ouzemmour Béaia 06000 (Algérie) LR Biotechnology and Bio-Geo Resources Valorization Higher Institute for Biotechnology University of Manouba Sidi Thabet Biotechpole 2020 Sidi Thabet Ariana 2080 (Tunisia) cE3c-Centre for Ecology Evolution and Environmental Changes Campo Grande Bloco C-2 Piso 5 Sala 03 Lisboa 1749-016 CPor- tugal)

Soil salinity, which affects more than 6% of the earth’s land surface and more than 20% of its irrigated areas, is a major threat to agriculture. Diazotrophic bacteria are among the functional groups of soil microbiota that are threatened by this abiotic stress, as their activity is mostly inhibited by salt stress. Seventy bacterial strains with distinct characteristics were isolated from soils by using N-free Jensen’s selective medium. Based on their ability to produce metabolites of agricultural interest, four strains were selected and identified as Flavobacterium johnsoniae, Pseudomonas putida, Achromobacter xylosoxidans, and Azotobacter chroococcum. The selected strains were grown at different NaCl concentrations (0–600 mmol L^(-1) in N-free broth and 0–2 000 mmol L^(-1) in Luria-Bertani medium) in the presence and absence of glycine betaine (GB), aqueous and hydro-alcoholic extracts from marine macroalgae, Ulva lactuca and Enteromorpha intestinalis, and Opuntia ficus-indica cladodes. The selected bacterial strains, GB, and the aforementioned extracts were tested for their ability to promote the germination of wheat (Triticum durum) seeds at 0–300 mmol L^(-1) NaCl. Compared with the results obtained with the synthetic osmoprotectant GB, the extracts from O. ficus-indica, U. lactuca, and E. intestinalis significantly promoted bacterial growth and seed germination under salt stress.

关键词： glycine betaine Ulva lactuca Enteromorpha intestinalis plant growth-promoting rhizobacteria (PGPR) seed germi-nation Triticum durum

The effect of rippling on the mechanical properties of graphene

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Nano Materials Science 2022年第1期4卷 18-26页

作者： Guillermo Lopez-Polin cristina Gomez-Navarro Julio Gomez-Herrero Instituto de Ciencia de Materiales de Madrid CSICMadrid E 28049Spain Departamento de Física de La Materia Condensada Universidad Autónoma de MadridMadridE-28049Spain IFIMAC Condensed Matter Physics Center(IFIMAC).Universidad Autónoma de Madrid MadridE-28049Spain

Graphene is the stiffest material known so far but, due to its one-atom thickness, it is also very ***, free-standing graphene exhibit ripples that has major effects on its elastic properties. Here we will summarize three experiments where the influence of rippling is essential to address the results. Firstly, we observed that atomic vacancies lessen the negative thermal expansion coefficient(TEC) of free-standing *** also observed an increase of the Young's modulus with global applied strain and with the introduction of small density defects that we attributed to the decrease of rippling. Here, we will focus on a surprising feature observed in the data: the experiments consistently indicate that only the rippling with wavelengths between 5 and 10 nm influences the mechanics of graphene. The rippling responsible of the negative TEC and anomalous elasticity is thought to be dynamic, i.e. flexural phonons. However, flexural phonons with these wavelengths should have minor effects on the mechanics of graphene, therefore other mechanisms must be considered to address our observations. We propose static ripples as one of the key elements to correctly understand the thermomechanics of graphene and suggest that rippling arises naturally due to a competition of symmetry breaking and anharmonic fluctuations.

关键词： Graphene Mechanical properties Atomic force microscopy Defects Ripples Stmain

Determination of future land use changes using remote sensing imagery and artificial neural network algorithm:A case study of Davao City,Philippines

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Artificial Intelligence in Geosciences 2023年第1期4卷 111-118页

作者： cristina E.Dumdumaya Jonathan Salar Cabrera College of Information and Computing University of Southeastern PhilippinesBrgy.ObreroDavao CityPhilippines Faculty of Computing Data SciencesEngineering and TechnologyDavao Oriental State UniversityMati CityDavao Oriental8200Philippines

Land use and land cover(LULC)changes refer to alterations in land use or physical *** changes can be caused by human activities,such as urbanization,agriculture,and resource extraction,as well as natural phenomena,for example,erosion and climate *** changes significantly impact ecosystem services,biodiversity,and human *** this study,LULC changes in Davao City,Philippines,were simulated,predicted,and projected using a multilayer perception artificial neural network(MLP-ANN)*** MLP-ANN model was employed to analyze the impact of elevation and proximity to road networks(i.e.,exploratory maps)on changes in LULC from 2017 to *** predicted 2021 LULC map shows a high correlation to the actual LULC map of 2021,with a kappa index of 0.91 and a 96.68%*** MLP-ANN model was applied to project LULC changes in the future(i.e.,2030 and 2050).The results suggest that in 2030,the built-up area and trees are increasing by 4.50%and 2.31%,***,water will decrease by up to 0.34%,and crops is about to decrease by approximately 3.25%.In the year 2050,the built-up area will continue to increase to 6.89%,while water and crops will decrease by 0.53%and 3.32%,***,the results show that anthropogenic activities influence the land’s ***,the study illustrates how machine learning models can generate a reliable future scenario of land usage changes.

关键词： LULC Artificial neural network Remote sensing Land use land cover prediction Multilayer perception Philippines

High-Order Symplectic Schemes for Stochastic Hamiltonian Systems

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Communications in Computational Physics 2014年第6期16卷 169-200页

作者： Jian Deng cristina Anton Yau Shu Wong Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAB T6G 2G1Canada. Department of Mathematics and Statistics Grant MacEwan UniversityEdmontonAB T5J 4S2Canada.

The construction of symplectic numerical schemes for stochastic Hamiltonian systems is *** approach based on generating functions method is proposed to generate the stochastic symplectic integration of any desired *** general the proposed symplectic schemes are fully implicit,and they become computationally expensive for mean square orders greater than ***,for stochastic Hamiltonian systems preserving Hamiltonian functions,the high-order symplectic methods have simpler forms than the explicit Taylor expansion schemes.A theoretical analysis of the convergence and numerical simulations are reported for several symplectic *** numerical case studies confirm that the symplectic methods are efficient computational tools for long-term simulations.

关键词： Stochastic Hamiltonian systems symplectic integration mean-square convergence high-order schemes.

Individualized hepatocellular carcinoma risk: The challenges for designing successful chemoprevention strategies

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World Journal of Gastroenterology 2013年第9期19卷 1359-1371页

作者： cristina Della Corte Alessio Aghemo Massimo Colombo AM Migliavacca Center for Liver Diseases First Division of Gastroenterology Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Università degli Studi di Milano 20122 Milan Italy

Hepatocellular carcinoma (HCC) develops in the context of environmental risk factors like chronic viral hepatitis, diabetes and alcohol exposure, often associated to an increased risk of cirrhosis. Antiviral treatments that are effective to counteract hepatitis B and C may also attenuate the risk of tumor development. However, since hepatitis B-related carcinogenesis is promoted independently of the onset of cirrhosis, such antiviral treatments as nucleo(t)side analogs can promote regression of cirrhosis, prevent clinical decompensation and variceal bleeding but not HCC. This means that in successfully treated patients with cirrhosis, HCC is often the consequence of their extended survival. In hepatitis C patients, a sustained virological response to interferon-based therapies can reduce the rate of HCC development, even in patients with cirrhosis who experience histological regression of their liver disease. Future therapies aimed at this endpoint in at risk populations should take into consideration pretreatment patient stratification for host, viral and environmental risk factors. In this context the recent discovery of single nucleotide polymorphisms involved in the immune system function and tumorigenesis, might permit enrollment of populations of patients enriched with HCC risk factors for targeted chemopreventive therapies. This could finally pave the way to personalized algorithms, as already seen in the diagnosis and treatment schemes for chemoprevention.

关键词： Hepatocellular carcinoma Hepatitis C virus Peginterferon Hepatitis B virus Human immunodeficiency virus Nucleoside analogues Sustained virological response Single nucleotide polymorphisms

Effect of pier shape and pier alignment on the equilibrium scour depth at single piers

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International Journal of Sediment Research 2016年第3期31卷 244-250页

作者： cristina Fael Rui Lana António Cardoso Faculdade de Engenharia Universidade da Beira InteriorEdificio Ⅱ das EngenhariasCalcada Fonte da Lameiro Instituto Superior de Engenharia/Universidade do Algarve Instituto Superior Tecnico Universidade de Lisboa

The equilibrium scour depth at uniform single bridge piers depends on a large number of variables,including the pier horizontal cross-section shape and its alignment angle towards the flow *** influence of these variables has been studied by only a few researchers,mostly,on the basis of tests that were far from approaching *** experimental study aims at revisiting the influence of piers’ shape and alignment on local scouring for length-width ratios smaller than or equal to 4,by increasing the experimental *** five long-duration laboratory tests were run under steady,clear-water flow,close to the threshold for initiation of sediment *** pier shapes were considered:circular,rectangular square-nosed,rectangular round-nosed,oblong,and zero-spacing(packed) pile-groups;the tested skew-angles were 0°,30°,45°,60°,and 90°.It was concluded that i) the shape factor can be taken as 1.0,for rectangular round-nosed and oblong cross-section piers,and as 1.2,for rectangular squarenosed and packed pile-group cross-section piers,ii) the shape factor does not vary significantly with the duration of tests,this way confirming the robustness of the shape factors reported to date,iii) the effect of shape is present at skewed piers although the associated coefficients remain in the narrow range of1.0-1.2,and iv) for length-width ratios smaller than 4,the shape factor is of the same order of magnitude as the skew angle factor and should not be neglected.

关键词： Scour Pier shape Pier alignment

Effect of asphalt thin beams mixed with three nominal maximum aggregate sizes in the bending beam rheometer on the prediction of thermal properties of bituminous material

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 1-7页

作者： Chun-Hsing HO Maria Francisca Martinez GONZALEZ cristina Pilar Martin LINARES Department of Civil Engineering Construction Management and Environmental Engineering Northern Arizona UniversityFlagstaff Arizona 86001 USA

The objective of this research is to evaluate an impact of asphalt mixture beams with varying sizes of aggregate in the Bending Beam Rheometer （BBR） for testing/predicting thermal cracking properties of asphalt pavements. The BBR test has following benefits： the equipment is cheaper, it uses smaller specimens, faster conditioning, easier availability for quality control, easier to manage, etc. However some concerns have been raised： some consider that the size of the aggregate may affect the test＇s results; the other concern is that such small beams cannot represent the whole properties of the asphalt pavement. To address these criticisms, imaging techniques, statistical analysis, and viscoelastic modeling are used. Asphalt thin beams prepared with three different nominal maximum aggregate size （NMAS）（12.5mm, 9.5 mm, and 4.75 mm） were tested at three different temperatures （-18℃, -24℃, and -30℃）. Based on results from statistical analyses and viscoelasticity, the ratio of asphalt binders and voids and stiffness differences among the three NMAS specimens are not significant, meaning that the impact of asphalt thin beams prepared with the three NMAS on the prediction of thermal cracking is minimal and can be neglected.

关键词： bending beam rheometer thin beams thermal cracking