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Oil recovery tests with ionic liquids: A review and evaluation of 1-decyl-3-methylimidazolium triflate

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Petroleum Science 2022年第4期19卷 1877-1887页

作者： Alba Somoza Alberto Arce ana Soto CRETUS Department of Chemical EngineeringUniversidade de Santiago de CompostelaE-15782Santiago de CompostelaSpain School of Engineering Universidade de A CorunaE-15403FerrolSpain

The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve current chemical oil recovery methods has been presented, focusing on core flooding experiments. With an almost infinite number of possible ionic liquids, the amount of experiments carried out up to now has been very limited. However, results are promising, with additional recovery after secondary flooding of up to 32% of the original oil in place. Most formulations with ionic liquids have been proposed for sandstone reservoirs, the number of studies with carbonate cores being very scarce. The possibilities of a new room temperature surface active ionic liquid, 1-decyl-3-methylimidazolium triflate,for this application were analyzed. It was shown that it is able to drastically reduce the water/oil interfacial tension. An optimized formulation was proposed for carbonate reservoirs. After secondary flooding with brine, an additional recovery of 10.5% of original oil in place was achieved at room conditions. A combination of the proposed method followed by a polymer flooding step with polyacrylamide led to a lesser but still significant recovery, reducing the costs associated to the ionic liquid.

关键词： Enhanced oil recovery(EOR) Ionic liquids Core flooding Interfacial tension 1-Decyl-3-methylimidazolium triflate

Oxidative stress modulation in hepatitis C virus infected cells

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World Journal of Hepatology 2015年第29期7卷 2880-2889页

作者： Sonia A Lozano-Sepulveda Owen L Bryan-Marrugo Carlos Cordova-Fletes Maria C Gutierrez-ruiz ana M Rivas-Estilla Department of Biochemistry and Molecular Medicine School of MedicineUniversidad Autonoma de Nuevo LeonMonterreyNuevo Leon 64460Mexico Department of Health Sciences Biological Sciences and Health DivisionSchool of Biological SciencesUniversidad Autonoma Metropolitana

Hepatitis C virus(HCV) replication is associated with the endoplasmic reticulum, where the virus can induce cellular stress. Oxidative cell damage plays an important role in HCV physiopathology. Oxidative stress is triggered when the concentration of oxygen species in the extracellular or intracellular environment exceeds antioxidant defenses. Cells are protected and modulate oxidative stress through the interplay of intracellular antioxidant agents, mainly glutathione system(GSH) and thioredoxin; and antioxidant enzyme systems such as superoxide dismutase, catalase, GSH peroxidase, and heme oxygenase-1. Also, the use of natural and synthetic antioxidants(vitamin C and E, N-acetylcysteine, glycyrrhizin, polyenylphosphatidyl choline, mitoquinone, quercetin, S-adenosylmethionine and silymarin) has already shown promising results as co-adjuvants in HCV therapy. Despite all the available information, it is not known how different agents with antiviral activity can interfere with the modulation of the cell redox state induced by HCV and decrease viral replication. This review describes an evidence-based consensus on molecular mechanisms involved in HCV replication and their relationship with cell damage induced by oxidative stress generated by the virus itself and cell antiviral machinery. It also describes some molecules that modify the levels of oxidative stress in HCV-infected cells.

关键词： Hepatitis C virus Oxidative stress Reactiveoxygen species Vitamin E Antioxidants Glycyrrhizin S-adenosylmethionine N-acetylcysteine Silymarin

Mineralogical signatures and sources of recent sediment in a large tropical lake

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International Journal of Sediment Research 2018年第2期33卷 183-190页

作者： Jorge Feliciano Ontiveros-Cuadras ana Carolina ruiz-Fernández Joan-Albert Sanchez-Cabeza Libia Hascibe Pérez-Bernal Michel Preda Federico Páez-Osuna Polytechnic University of Sinaloa (UPSIN) Mazatlan Academic Unit Institute of Marine Sciences and LimnologyNational Autonomous University of Mexico (UNAM) Oceanic and Coastal Processes Academic Unit Institute of Marine Sciences and LimnologyNational Autonomous University of Mexico (UNAM).University City Department of Earth and Atmospheric Sciences University of Quebec in Montreal (UQAM)

Two lead-210(210Pb) dated sediment cores from Chapala Lake were studied to identify the mineral composition of the sediments and to discuss its relation with trace metals. Minerals and trace metals reflected the domain of volcanic rocks(i.e. basalts, rhyolite and andesite) that characterize Chapala Lake and the Lerma River watershed. Redundancy analyses(RDA) were used to identify the sedimentary variables(magnetic susceptibility, organic matter, sand content, and mineral composition) that could be related to elemental composition. Despite the distance between the two cores(7.3 km) and hydrodynamic circulation the RDA showed that the main mechanism that controls the input of mineral species,and, therefore, element distributions in the lacustrine sediment of Chapala Lake, is related to the weathering of volcanic rocks in the Lerma-Chapala watershed, the consequent runoff and transport of fine grained catchment materials, and later in-lake processes. These findings highlight the importance of controlling watershed erosion to contribute to the improvement of the environmental quality of the lake.

关键词： Chapala Lake Trace metals Mineralogy Lacustrine sediments

Synthetic gauge fields for ultracold atoms

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National Science Review 2016年第2期3卷 166-167页

作者： ana Maria Rey JILA NIST and Department of PhysicsUniversity of Colorado

Ultracold gases are remarkably versatile and controllable systems with untapped potential to emulate a variety of quantum phenomena[1].Atoms are,however,electrically neutral and therefore it is highly desirable to make them behave as charged *** capability has recently been demonstrated in a series of recent experiments[2-4].Although many challenges remain ahead,

关键词： Synthetic gauge fields for ultracold atoms

Ethanol exposed maturing rat cerebellar granule cells show impaired energy metabolism and increased cell death after oxygen-glucose deprivation

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Neural Regeneration Research 2019年第3期14卷 485-490页

作者： ana Spataru Diana Le Duc Leon Zagrean ana-Maria Zagrean Division of Physiology and Neuroscience Carol Davila University of Medicine and Pharmacy King's College Hospital London UK Institute of Human Genetics University of Leipzig Hospitals and Clinics Leipzig GermanyDepartment of Evolutionary Genetics Max Planck Institute for Evolutionary Anthropology

Alcohol, a widely abused drug, has deleterious effects on the immature nervous system. This study investigates the effect of chronic in vitro ethanol exposure on the metabolism of immature rat cerebellar granular cells(CGCs) and on their response to oxygen-glucose deprivation(OGD). Primary CGC cultures were exposed to ethanol(100 mM in culture medium) or to control ethanol-free medium starting day one in vitro(DIV1). At DIV8, the expression of ATP synthase gene ATP5 g3 was quantified using real-time PCR, then cultures were exposed to 3 hours of OGD or normoxic conditions. Subsequently, cellular metabolism was assessed by a resazurin assay and by ATP level measurement. ATP5 g3 expression was reduced by 12-fold(P = 0.03) and resazurin metabolism and ATP level were decreased to 74.4 ± 4.6% and 55.5 ± 6.9%, respectively after chronic ethanol treatment compared to control values(P < 0.01). Additionally, after OGD exposure of ethanol-treated cultures, resazurin metabolism and ATP level were decreased to 12.7 ± 1.0% and 9.0 ± 2.0% from control values(P < 0.01). These results suggest that chronic ethanol exposure reduces the cellular ATP level, possibly through a gene expression down-regulation mechanism, and increases the vulnerability to oxygen-glucose deprivation. Thus, interventions which improve metabolic function and sustain ATP-levels could attenuate ethanol-induced neuronal dysfunction and should be addressed in future studies.

关键词： cell culture chronic ethanol exposure oxygen-glucose deprivation cerebellar granule cells toxicity gene expression cellular ATP cellular metabolism metabolic impairment cell death

Comparison of transient and stable expression of foot-and-mouth disease virus capsid proteins in mammalian cells

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Advances in Bioscience and Biotechnology 2013年第12期4卷 1024-1029页

作者： ana Clara Mignaqui Vanesa ruiz Andrés Wigdorovitz Instituto de Virología Instituto Nacional de Tecnología Agropecuaria Hurlingham Argentina

Foot-and-mouth disease is a highly contagious disease that produces severe economic losses in the livestock industry. This disease is being controlled by the use of an inactivated vaccine. However, the use of recombinant empty capsids as a subunit vaccine has been reported to be a promising candidate because it avoids the use of virus in the vaccine production. A plasmid containing the capsid precursor P12A and protease 3C sequences of foot-and-mouth disease virus (FMDV) was constructed and used to compare transient and stable expression in mammalian cells. When BHK-21 cells were transfected with the recombinant vector, protease 3C cleaved the capsid precursor P12A into the structural proteins VP0, VP1 and VP3. A sucrose gradient demonstrated that the structural proteins assembled into different subviral particles. Attempts to generate a stable cell line only allowed isolating low-level-expressing clones, probably due to the effect of protease 3C on the cells. Moreover, the recombinant protein yield achieved in transient expression assays was much higher than the one achieved in stable expression assays. Results indicate that mammalian cells are a good strategy to produce recombinant FMDV subviral particles. However, the alternative approach of transient gene expression in scalable systems should be used instead of the standard method that involves the generation of a stable cell line.

关键词： Empty Capsids Foot and Mouth Disease Virus Mammalian Cells Stable Expression Transient Ex-pression

Children in Disaster Risk Reduction in Portugal: Policies,Education,and (Non) Participation

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International Journal of Disaster Risk Science 2017年第3期8卷 246-257页

作者： ana Delicado ussara Rowland Susana Fonseca ana Nunes de Almeida Luísa Schmidt ana Sofia Ribeiro Instituto de Ciências Sociais Universidade de Lisboa1600-189 LisbonPortugal

International agencies and scientific research have been calling for the inclusion of children in disaster preparedness and risk reduction, to hear their voices in order to address their specific needs and vulnerabilities and harness their capabilities in terms of building community resilience. This article assesses the roles ascribed to children in policy and education for disaster risk reduction in Portugal. The approach is based on a scoping methodology that encompasses document analysis and interviews with national and local stakeholders and policymakers in the disaster risk reduction field. The research is carried out within the scope of a European funded project, CUIDAR Cultures of Disaster Resilience among Children and Young People. More specifically, the article provides an overview of the discourses on the roles ascribed to children in urban disaster risk reduction(DRR). The authors maintain that although children are often taken as a target group in urban disaster prevention and management, they are seldom considered in terms of active participation in disaster risk reduction programs in the Portuguese context. Nevertheless, our analysis shows that there is a growing awareness of the relevance of active participation by children in order to create successful DRR.

关键词： Children’s nonparticipation Disaster risk reduction Emergency planning Portugal Risk education

Genetic Identification of Quantitative Trait Loci for Contents of Mineral Nutrients in Rice Grain

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Journal of Integrative Plant Biology 2009年第1期51卷 84-92页

作者： ana Luisa Garcia-Oliveira Department of Plant Genetics and Breeding and State Key Laboratory of Plant Physiology and Biochemistry China Agricultural University National Centre for Evaluation of Agricultural Wild Plant Rice Beijing Key Laboratory of Crop Genetic Improvement and Genome of Ministry of Agriculture

In present study, Fe, Zn, Mn, Cu, Ca, Mg, P and K contents of 85 introgression lines （ILs） derived from a cross between an elite indica cultivar Teqing and the wild rice （Oryza rufipogon） were measured by inductively coupled argon plasma （ICAP） spectrometry. Substantial variation was observed for all traits and most of the mineral elements were significantly positive correlated or independent except for Fe with Cu. A total of 31 putative quantitative trait loci （QTLs） were detected for these eight mineral elements by single point analysis. Wild rice （O. rufipogon） contributed favorable alleles for most of the QTLs （26 QTLs）, and chromosomes 1,9 and 12 exhibited 14 QTLs （45%） for these traits. One major effect of QTL for zinc content accounted for the largest proportion of phenotypic variation （11%-19%） was detected near the simple sequence repeats marker RM152 on chromosome 8. The co-locations of QTLs for some mineral elements observed in this mapping population suggested the relationship was at a molecular level among these traits and could be helpful for simultaneous improvement of these traits in rice grain by marker assisted selection.

关键词： introgression lines mineral elements Oryza sativa Oryza rufipogon quantitative trait loci.

Evolution of Texture in Grain Oriented Silicon Steels

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Journal of Iron and Steel Research International 2009年第4期16卷 78-83页

作者： Constantin Gheorghies ana Doniga Faculty of Science Dunarea de Jos University of Galati Faculty of Metallurgy and Materials Science Dunarea de Jos University of Galati

Goss texture or （110）[100] crystallographic orientation of the grains is typical grain structure of grain oriented silicon steel used for transformer. This type of texture is one of the most important parameters determining the magnetic properties of the laminated steel plates. The furination and growth of Goss texture in three steel samples are investigated. Two of them are prepared under laboratory conditions and one under industrial conditions. The em- phasis is put on the effects of hot lamination temperature and time, primary and secondary recrystallization temperatures during cold lamination on developing of the Goss texture in correlation with other texture components. Also in all steel processing stages, the influence of the chemical composition on the occurrence of Goss texture is examined.

关键词： silicon steel Goss texture hot rolling process recrystallization annealing temperature