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非常规油气开发中润湿性反转技术的应用

石油勘探与开发 2016年第5期43卷 764-771页

作者： alvarez J o SCHECHTER D S Texas A & M University

研究了适用于非常规油气储集层的岩石润湿性测量方法,总结了非常规油气储集层岩石润湿性特征,分析了非常规油气储集层岩石润湿性反转技术的应用情况,并介绍了研究表面活性剂与非常规油气储集层岩石润湿性间关系的实验方法。研究表明:接... 详细信息

研究了适用于非常规油气储集层的岩石润湿性测量方法,总结了非常规油气储集层岩石润湿性特征,分析了非常规油气储集层岩石润湿性反转技术的应用情况,并介绍了研究表面活性剂与非常规油气储集层岩石润湿性间关系的实验方法。研究表明:接触角法、核磁共振法和Zeta电位测量法是评估非常规油气储集层岩石润湿性最恰当的方法,非常规油气储集层呈现出中性润湿到油湿的混合润湿特性。润湿性反转技术在非常规油气储集层中的应用目前仅限于添加表面活性剂。在压裂液中加入表面活性剂可改变非常规油气储集层岩石润湿性从而提高原油采收率。借助稳定性实验、润湿性反转评估实验、界面张力实验、自吸实验、压吸实验和吸附实验等可评估表面活性剂改变润湿性及提高采收率的效率。

关键词：非常规油气储集层润湿性润湿性反转表面活性剂自吸提高原油采收率页岩油

Superplasticity of a friction stir processed overaged WE54 magnesium alloy

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Journal of Magnesium and Alloys 2022年第11期10卷 3156-3166页

作者： oscar A.Ruano Marta alvarez-Leal Alberto orozco-Caballero Fernando Carreño Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of R&D and programmes Technology Centre of Metal-Mechanical and Transport(CETEMET).Avda.1°de Mayos/n.LinaresJaén2370Spain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The coarse-grained WE54 magnesium alloy was heat treated in order to have minimum hardness minimizing the effects of precipitates and solid solution. Friction stir processing(FSP) was applied in severe conditions to obtain fine, equiaxed and highly misoriented grains, with grain sizes even less than 1 μm. The high severity of processing demonstrated to have a strong impact in the microstructure. Consequently,the processed materials exhibited excellent superplasticity at the high strain rate 10^(-2)s^(-1), and temperatures between 300 and 400 ℃. The maximum tensile superplastic elongation of 756% was achieved at 400 ℃ thanks to the operation of grain boundary sliding mechanism(GBS). Besides the new data obtained through tensile testing, the paper deals with a transcendental question regarding the large differences in strain rate values at a given stress in the superplastic regime at maximum elongation compared to other magnesium-based alloys. With this is mind, 19 magnesium alloys from 22 different investigations were analyzed to give some light to this behavior that never was treated before. It is proposed that this behavior has to be attributed to the accommodation process, necessary for GBS to occur, which is hindered by reinforcing solutes.

关键词： WE54 magnesium alloy Friction stir processing Processing severity Superplasticity Grain boundary sliding Solutes

New approaches to identification and characterization of tioconazole in raw material and in pharmaceutical dosage forms

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Journal of Pharmaceutical Analysis 2019年第1期9卷 40-48页

作者： Natalia L.Calvo Vera A.alvarez María C.Lamas Darío Leonardi Instituto de Química Rosario (IQUIR CONICET-UNR) área Análisis de Medicamentos Facultad de Ciencias Bioquímicas y Farmacéuticas Universidad Nacional de Rosario Grupo de Materiales Compuestos Termoplásticos (CoMP) Instituto de Investigaciones de Cienciay Tecnología de Materiales (INTEMA CONICET-UNMdP) área Técnica Farmacéutica Facultad de Ciencias Bioquímicas y Farmacéuticas Universidad Nacional de Rosario

Tioconazole(TCZ), a broad-spectrum antifungal agent, has significant activity against Candida albicans and other Candida species, and therefore, it is indicated for the topical treatment of superficial mycoses.The main goal of this work is to report an exhaustive identification and characterization procedure to improve and facilitate the online quality control and continuous process monitoring of TCZ in bulk material and loaded in two different dosage forms: ovules and nail lacquer. The methodologies were based on thermal(differential scanning calorimetry(DSC), melting point, and thermogravimetry(TG)),spectroscopic(ultraviolet(UV), Raman, near infrared(NIR), infrared spectroscopy coupled to attenuated total reflectance(FTIR-ATR), and nuclear magnetic resonance(NMR)), microscopic and X-ray diffraction(XRD). The TCZ bulk powder showed a high crystallinity, as observed by XRD, with a particles size distribution(3–95 mm) resolved by microscopic measurements. TCZ melting point(82.8 °C) and a degradation peak centered at 297.8 °C were obtained by DSC and DTG, respectively. An unambiguous structure elucidation of TCZ was obtained by mono-and two-dimensional1 H and13 C NMR spectral data analysis. The FTIR-ATR, Raman and NIR spectra of both the raw material and the commercial products were analyzed and their characteristic bands were tabulated. The best methods for TCZ identification in ovules were DSC, TG, XRD, NIR and Raman, while NIR and FTIR-ATR were the most appropriate techniques to analyze it in the nail lacquer. DSC, TG, DRX, Raman, FTIR-ATR and NIR spectroscopy are effective techniques to be used in online process analysis, because they do not require sample preparation, and they are considerably sensitive to analyze complex samples.

关键词： Tioconazole Identification Characterization Pharmaceutical dosage forms Spectroscopic methods

Proteomic analysis of F_(1)hybrids and intermediate variants in a Littorina saxatilis hybrid zone

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Current Zoology 2022年第3期68卷 351-359页

作者： Angel P.DIZ Mónica R.RoMERo Juan GALINDo María SAURA David o.F.SKIBINSKI Emilio RoLÁN-alvarez Centro de Investigación Mariña(CIM-UVIGo) Universidade de VigoVigo 36310Spain Departamento de Mejora Genética Animal INIAMadrid 28040Spain Institute of Life Science Swansea University Medical SchoolSwansea SA28PPUK

Proteomic analysis was carried out on the Crab(upper-shore)and Wave(lower-shore)ecotypes of Littorina saxatilis from a hybrid zone at Silleiro Cape,Spain.Proteome profiles of individual snails were obtained.Protein expression in F_(1)hybrid snails bred in the laboratory and snails with intermediate shell phenotypes collected from the mid-shore were compared with Crab and Wave ecotypes using analytical approaches used to study dominance.Multivariate analysis over many protein spots showed that the F_(1)snails are distinct from both ecotypes but closer to the Wave ecotype.The intermediate snails are highly variable,some closer to the Crab and others to the Wave ecotype.Considered on a protein by protein basis,some proteins are significantly closer in expression to the Crab and others to the Wave ecotype for both F_(1)and intermediate snails.Furthermore,a significant majority of proteins were closer in expression to the Wave ecotype for the F_(1),consistent with the multivariate analysis.No such significant majority toward either the Crab or Wave ecotype was observed for the intermediate snails.The closer similarity of F_(1)and Wave ecotype expression patterns could be the result of similar selective pressures in the similar mid-shore and low-shore environments.For a significantly larger number of proteins,intermediate snails were closer in expression to the ecotype having the lower expression,for both Crab and Wave ecotypes.This is somewhat unexpected as lower expression might be expected to be an indication of impairment of function and lower fitness.Proteomic analysis could be important for the identification of candidate proteins useful for gaining improved understanding of adaptation and barriers to gene flow in hybrid zones.

关键词： F_(1)hybrids gene expression marine invertebrates molecular phenotype reproductive isolation speciation

Fighting type 2 diabetes: Formulation strategies for peptide-based therapeutics

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Acta Pharmaceutica Sinica B 2022年第2期12卷 621-636页

作者： Carlos Bendicho-Lavilla Iria Seoane-Viano Francisco J.oteroEspinar Asteria Luzardo.alvarez Department of Pharmacology Pharmacy and Pharmaceutical TechnologyFaculty of PharmacyUniversity of Santiago de Compostela(USC)Santiago de Compostela 15782Spain Paraquasil Group Health Research Institute of Santiago de Compostela(IDIS)Santiago de Compostela 15706Spain Department of Pharmacology Pharmacy and Pharmaceutical TechnologySchool of SciencesCampus de LugoUniversity of Santiago de CompostelaLugo 27002Spain

Diabetes mellitus is a major health problem with increasing prevalence at a global level.The discovery of insulin in the early 1900 s represented a major breakthrough in diabetes management,with further milestones being subsequently achieved with the identification of glucagon-like peptide-1(GLP-1)and the introduction of GLP-1 receptor agonists(GLP-1 RAs)in clinical practice.Moreover,the subcutaneous delivery of biotherapeutics is a well-established route of administration generally preferred over the intravenous route due to better patient compliance and prolonged drug absorption.However,current subcutaneous formulations of GLP-1 RAs present pharmacokinetic problems that lead to adverse reactions and treatment discontinuation.In this review,we discuss the current challenges of subcutaneous administration of peptide-based therapeutics and provide an overview of the formulations available for the different routes of administration with improved bioavailability and reduced frequency of administration.

关键词： Type 2 diabetes mellitus Glucagon-like peptide-1 receptor agonists Exenatide Subcutaneous administration Amylin mimetics Drug delivery systems Biotherapeutics Peptide delivery Controlled-release formulations Microparticles Nanoparticles

Approximating home ranges of humpback and fin whales in Drake Passage and Antarctica

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Advances in Polar Science 2020年第4期31卷 248-257页

作者： JoséLuis oRGEIRA Facundo.alvarez Departamento Biología de los Predadores Tope Instituto Antártico Argentino.Buenos AiresArgentina Programa de pós-graduação em Ecologia e Conservação.Campus de Nova Xavantina.Universidade do Estado de Mato Grosso Brasil

Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean study.Understanding these ranges facilitates identification of resource use and conservation.Fin and humpback whales occur in Antarctica during the austral summer,but information regarding their home ranges is limited.Using opportunistically collected whale sighting data from eight consecutive summer seasons spanning 2010–2017,we approximate the home ranges of humpback and fin whales around Drake Passage(DRA),West of Antarctic Peninsula(WAP),South Shetland Islands(SSI),an area northwest of the Weddell Sea(WED),and around the South orkney Islands(SoI).Approximate home ranges are identified using Kernel Density Estimation(KDE).Most fin whales occurred north and northwest of the SoI,which suggests that waters near these islands support concentrations of this species.Most humpback whales were observed around the SSI,but unlike fin whales,their distributions were highly variable in other areas.KDE suggests spatial segregation in areas where both species exist such as SoI,SSI,and WPA.Partial redundancy analysis(pRDA)suggests that the distributions of these species are more affected by spatial variables(latitude,longitude)than by local scale variables such as sea surface temperature and depth.This study presents a visual approximation of the home ranges of fin and humpback whales,and identifies variation in the effects of space and environmental variables on the distributions of these whales at different spatial scales.

关键词： humpback whale fin whale home range Antarctica Drake Passasge

SIMULATIoN oF o_(2)-BLoWN Co-GASIFICATIoN oF WooD CHIP AND PoTATo PEEL FoR PRoDUCING SYNGAS

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Frontiers of Agricultural Science and Engineering 2023年第3期10卷 448-457页

作者： Yulin HU Kang KANG Iker Zulbaran alvarez Nasim MIA Aadesh RAKHRA Faculty of Sustainable Design Engineering University of Prince Edward IslandCharlottetownPEC1A 4P3Canada Biorefining Research Institute Lakehead UniversityThunder BayONP7B 5E1Canada

Potato is the fifth largest agricultural crop in Canada and contributes to the generation of an abundant amount of potato peel.However,disposal/recycling this peel remains a challenge due to the stringent environmental regulations.Consequently,there is a lack of an appropriate recycling and valorization methods of potato peel.Gasification is an effective technology for producing syngas and an ecofriendly waste disposal approach.Syngas is an important industrial intermediate to produce synthetic fuels and chemicals.To develop an ecofriendly and cost-effective valorization approach for potato peel,this study used a mixture of woody biomass(i.e.,wood chips)and potato peel to produce syngas by co-gasification using o_(2) as the gasifying agent at a constant equivalence ratio of 0.3 using Aspen Plus simulation software.The influences of gasification temperature and wood chip/potato peel weight ratio on the carbon conversion efficiency(CCE),and product gas composition(molar fraction)and lower heating value(LHV)of product gas were investigated.This simulation indicated that a positive synergistic interaction occurs between wood chips and potato peel in co-gasification process in terms of an increase in CCE by comparing the arithmetic value and real value at all simulated wood chip to potato peel weight ratios(44.9%to 85.8%,46.5%to 76.2%,and 48.1%to 78.6%at ratios of 25:75,50:50,and 75:25,respectively,for wood chips to potato peel).While the molar fraction of H_(2) and Co decreased continuously with increase in the weight percentage of wood chips in the wood chip-potato peel mixture from 0 wt%to 100 wt%(H_(2),at 42.1 mol%to 41.4 mol%;and Co at 44.0 mol%to 40.4 mol%),accompanied by a decrease of the LHV of the product gas(10.3 to 9.78 MJ·Nm^(−3)).The study concluded that co-gasification for producing syngas is feasible and environmental-friendly option to recycle and valorize potato peel.

关键词： Aspen Plus co-gasification potato peel syngas simulation waste reduction wood chip

Addition of phenolic compounds to bread: antioxidant benefits and impact on food structure and sensory characteristics

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Food Production, Processing and Nutrition

Food Production, Processing and Nutrition 2021年第1期3卷 314-325页

作者： Yesica A.Czajkowska–González Emilio.alvarez–Parrilla Nina del Rocío Martínez–Ruiz Alma A.Vázquez–Flores Marcela Gaytán–Martínez Laura Ade la Rosa Departament of Chemical Biological Sciences Institute of Biomedical SciencesUniversidad Autónoma de Ciudad JuárezAnillo Envolvente del PRONAF y Estocolmos/nC.P.32310 Cd.JuárezMéxico Programa de Posgrado en Alimentos del Centro de la República(PRoPAC) Research and Graduate Studies in Food ScienceSchool of ChemistryUniversidad Autónoma de QuerétaroCentro UniversitarioCerro de las Campanas S/NC.P.76010 Santiago de QuerétaroMexico

The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional food.However,phenolic compounds present great structural diversity,as well as the ability to interact in a complex way with the macromolecules that constitute the bread matrix.Therefore,the addition of these flours,extracts or pure compounds produces various effects on the microstructure of bread,and several of its sensory properties.This is mainly due to interactions between phenolic compounds and gluten proteins.The objective of this review is to analyze some of the most recent published works on the addition of phenolic compounds in wheat bread to identify the type of positive and negative effects that have been observed and how they can be related to the physicochemical interactions between phenolic compounds and the macromolecules that constitute the food matrix,mainly gluten.The effect of monomeric and polymeric phenolic compounds on the strength of these interactions and on the properties of dough and bread are discussed.

关键词： condensed tannins hydrolysable tannins phenolic acids gluten food rheology food texture protein-phenolic interactions disulfide bonds non-covalent interactions

Mitochondrial Sulfide Detoxification Requires a Functional Isoform o-Acetylserine（thiol）lyase C in Arabidopsis thaliana

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Molecular Plant 2012年第6期5卷 1217-1226页

作者： Consolacien alvarez Irene Garcia Luis C Romero Cecilia Gotor Instituto de Bioquimica Vegetal y Fotosintesis Consejo Superior de Investigaciones Cientificas y Universidad de Sevilla Avda. Am~rico Vespucio 49 41092Sevilla Spain

In non-cyanogenic species, the main source of cyanide derives from ethylene and camalexin biosyntheses. In mitochondria, cyanide is a potent inhibitor of the cytochrome c oxidase and is metabolized by the β-cyanoalanine synthase CYS-C1, catalyzing the conversion of cysteine and cyanide to hydrogen sulfide and β-cyanoalanine. The hydrogen sulfide released also inhibits the cytochrome c oxidase and needs to be detoxified by the o-acetylserine（thiol）lyase mitochondrial isoform, oAS-C, which catalyzes the incorporation of sulfide to o-acetylserine to produce cysteine, thus generating a cyclic pathway in the mitochondria. The loss of functional oAS-C isoforms causes phenotypic characteristics very similar to the loss of the CYS-C1 enzyme, showing defects in root hair formation. Genetic complementation with the oAS-Cgene rescues the impairment of root hair elongation, restoring the wild-type phenotype. The mitochondria compromise their capacity to properly detoxify cyanide and the resulting sulfide because the latter cannot re-assimilate into cysteine in the oas-c null mutant. Consequently, we observe an accumulation of sulfide and cyanide and of the alternative oxidase, which is unable to prevent the production of reactive oxygen species probably due to the accumulation of both toxic molecules. our results allow us to suggest that the significance of oAS-C is related to its role in the proper sulfide and cyanide detoxification in mitochondria.

关键词： alternative oxidase Arabidopsis thaliana cysteine cyanide β-cyanoalanine synthase o-acetylserine（thiol）-lyase reactive oxygen species root hair sulfide.