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Simplification workflow for hydraulically fractured reservoirs

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Petroleum 2018年第2期4卷 134-147页

作者： raul Velasco Palash Panja Milind Deo Energy&Geoscience Institute Salt Lake CityUSA Department of Chemical Engineering The University of UtahSalt Lake CityUSA

Production from unconventional formations,such as shales,has significantly increased in recent years by stimulating large portions of a reservoir through the application of horizontal drilling and hydraulic *** oil shales are heavily dependent on oil prices,production forecasts remain positive in the North-American *** to the complexity of hydraulically fractured tight formations,reservoir numerical simulation has become the standard tool to assess and predict production performance from these unconventional *** of these unconventional fields are immense,consisting of multistage and multiwell projects,which results in impractical simulation run ***,simplification of large-scale simulation models is now common both in the industry and *** simplified models such as the“single fracture”approach do not often capture the physics of large-scale projects which results in inaccurate *** this paper we present a simple,yet rigorous workflow that generates simplified representative models in order to achieve low simulation run times while capturing physical phenomena which is fundamental for accurate *** proposed workflow is based on consideration of representative portions of a large-scale model followed by postprocess scaling to obtain desired full model *** simplified models that result from the application of the proposed workflow for a single well and a multiwell case are compared to full-scale models and the“single fracture”*** of fluid rates and cumulative production show that accurate results are possible for simplified models if all important components for a particular case are taken into ***,application of the workflow is shown for a heterogeneous field case where prediction studies can be carried out.

关键词： Hydraulic fracture Shale Simulation workflow Multiwell Field case

Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen Simon Hettler Ashwin Ramasubramaniam raul Arenal Ronen Bar-Ziv Maya Bar Sadan Department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel Department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain Department of Mechanical and Industrial Engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

Novel strategies to tailor the photocatalytic activity of metal–organic frameworks for hydrogen generation: a mini-review

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Frontiers in Energy 2022年第5期16卷 734-746页

作者： Luis A.ALFONSO-herrera Leticia M.TORRES-MARTINEZ J.Manuel MORA-HERNANDEZ Universidad Autónoma de Nuevo León UANLFacultad de Ingeniería CivilDepartamento de Ecomateriales y EnergíaAv.Universidad S/N Ciudad UniversitariaSan Nicolás de los GarzaNuevo León 66455México Centro de Investigación en Materiales Avanzados S.C.(CIMAV)Miguel de Cervantes No.120.Complejo Ind.ChihuahuaChihuahuaChih 31136México CONACYT-Universidad Autónoma de Nuevo León UANLFacultad de Ingeniería CivilDepartamento de Ecomateriales y EnergíaAv.Universidad S/N Ciudad UniversitariaSan Nicolás de los GarzaNuevo León 66455México

This review provides a recompilation of the most important and recent strategies employed to increase the efficiency of metal-organic framework(MOF)-based systems toward the photocatalytic hydrogen evolution(PHE)reaction through specific strategies:tailoring the photocatalytic activity of bare MOFs and guest@MOF composites,formation of heterojunctions based on MOFs and various photocatalysts,and inorganic photocatalysts derived from *** to the data reported in this mini-review,the most effective strategy to improve the PHE of MOFs relies on modifying the linkers with new secondary building units(SBUs).Although several reviews have investigated the photocatalytic activity of MOFs from a general point of view,many of these studies relate this activity to the physicochemical and catalytic properties of ***,they did not consider the interactions between the components of the photocatalytic *** study highlights the effects of strength of the supramolecular interactions on the photocatalytic performance of bare and MOF-based materials during PHE.A thorough review and comparison of the results established that metal-nanoparticle@MOF composites have weak van der Waals forces between components,whereas heterostructures only interact with MOFs at the surface of bare *** material derivatives from MOFs,we found that pyrolysis destroyed some beneficial properties of MOFs for ***,we conclude that adding SBUs to organic linkers is the most efficient strategy to perform the PHE because the SBUs added to the MOFs promote synergy between the two materials through strong coordination bonds.

关键词： metal-organic frameworks(MOFs) photocatalytic hydrogen evolution MOF heterojunctions materials derived from MOFs bandgap recombination

Methylation of DAPK and THBS1 genes in esophageal gastric-type columnar metaplasia

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World Journal of Gastroenterology 2016年第18期22卷 4567-4575页

作者： Roberto herrera-Goepfert Luis F Onate-Ocana José Luis Mosqueda-Vargas Luis A herrera Clementina Castro Julia Mendoza Rodrigo González-Barrios Department of Pathology Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Clinical Research Division Instituto Nacional de Cancerologia (INCan) 10480 Mexico DF Mexico Unidad de Investigacion Biomedica en Cancer Instituto Nacional de Cancerologia (INCan)-Instituto de Investigaciones Biomedicas (IIB) Universidad Nacional Autonoma de Mexico (UNAM) 14080 Mexico DF Mexico

AIM: To explore methylation of DAPK, THBS1, CDH-1, and p14 genes, and Helicobacter pylori(H. pylori) status in individuals harboring esophageal columnar ***: Distal esophageal mucosal samples obtained by endoscopy and histologically diagnosed as gastric-type(non-specialized) columnar metaplasia, were studied thoroughly. DNA was extracted from paraffin blocks, and methylation status of deathassociated protein kinase(DAPK), thrombospondin-1(THBS1), cadherin-1(CDH1), and p14 genes, was examined using a methyl-sensitive polymerase chain reaction(MS-PCR) and sodium bisulfite modification protocol. H. pylori cag A status was determined by ***: In total, 68 subjects(33 females and 35 males), with a mean age of 52 years, were included. H. pylori cag A positive was present in the esophageal gastric-type metaplastic mucosa of 18 individuals. DAPK, THSB1, CDH1, and p14 gene promoters were methylated by MS-PCR in 40(58.8%), 33(48.5%), 46(67.6%), and 23(33.8%) cases of the 68 esophageal samples. H. pyloristatus was associated with methylation of DAPK(P = 0.003) and THBS1(P = 0.019).CONCLUSION: DNA methylation occurs in cases of gastric-type(non-specialized) columnar metaplasia of the esophagus, and this modification is associated with H. pylori cag A positive infection.

关键词： DNA methylation Esophageal columnar metaplasia Thrombospondin-1 Death-associated protein kinase Helicobacter pylori cagA

Body Composition,Aerobic Fitness,Isokinetic Profile,and Vertical Jump Ability in Elite Male and Female Volleyball and Beach Volleyball Players

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Journal of Science in Sport and Exercise 2023年第4期5卷 385-395页

作者： raul Freire Matheus Hausen Glauber Pereira Alex Itaborahy Olympic Laboratory Brazil Olympic CommitteeRio de JaneiroBrazil Laboratory of Biomechanics and Motor Behavior Institute of Physical Education and SportsRio de Janeiro State UniversityRio de JaneiroBrazil

Purpose This study aimed to compare the physical attributes of male and female Volleyball and Beach Volleyball *** Fifty-five athletes from Volleyball(Male,n=19,age 27.3±6.1 years,body mass 93.2±9.9 kg,and height 196.8±7.4 cm and Female,n=16,age 28.0±5.6 years,body mass 76.9±8.8 kg,and height 179.9±5.8 cm)and Beach Volleyball(Male,n=10,age 26.8±3.4 years,body mass 92.9±9.9 kg,and height 195.3±7.9 cm and Female,n=10,age 31.1±6.2 years,body mass 74.6±8.5 kg,and height 180.9±6.0 cm)participated in the *** tests were performed in a single visit to the laboratory in the following order:body composition,vertical jump(squat and countermovement jump),isokinetic(knees and shoulders),and cardiopulmonary exercise *** variables were analyzed using a two-way ANOVA(Sex and Sport factors)for independent *** Beach Volleyball athletes presented lower body fat(P=0.03;ES=0.32)and higher maximal cardiorespiratory variables(VO2,HR,and vVO2max).Only flexion bilateral difference(knee)at 60°/s was affected by sex(P=0.002;ES=0.63).For shoulders,only dominant external/internal rotation ratio presented a significant interaction for sport and sex(P=0.05;ES=0.28).Regarding vertical jumps,Volleyball male players presented a greater elastic index than BV male players(P=0.002,ES=0.67).Conclusion Beach Volleyball players are thinner and have better cardiorespiratory fitness than Volleyball ***,they presented less use of elastic properties for vertical jumping and have a greater muscle imbalance in the hamstrings than Volleyball players.

关键词： Athlete profile Court VO2max Neuromuscular Sex Sport

SYNTHESIS AND PROPERTIES OF HOMOPOLYMER AND COPOLYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATALYSTS

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Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： raul Quijada Juan L.Guevara Rene Rojas Franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

Clostridium difficile and inflammatory bowel disease: Role in pathogenesis and implications in treatment

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World Journal of Gastroenterology 2013年第43期19卷 7577-7585页

作者： Orna Nitzan Mazen Elias Bibiana Chazan raul Raz Walid Saliba Infectious Disease Unit Ha’emek Medical CenterAfula 18101Israel Bruce Rappaport Faculty of Medicine Technion-Israel Institute of TechnologyHaifa 31096Israel Department of Internal Medicine C Ha’emek Medical CenterAfula 18101Israel

Clostridium difficile(***)is the leading cause of antibiotic associated colitis and nosocomial *** with inflammatory bowel disease(IBD)are at increased risk of developing *** infection(CDI),have worse outcomes of CDI-including higher rates of colectomy and death,and experience higher rates of ***,it is still not clear whether *** is a cause of IBD or a consequence of the inflammatory state in the intestinal *** burden of CDI has increased dramatically over the past decade,with severe outbreaks described in many countries,which have been attributed to a new and more virulent strain.A parallel rise in the incidence of CDI has been noted in patients with *** patients with CDI tend be younger,have less prior antibiotic exposure,and most cases of CDI in these patients represent outpatient acquired *** clinical presentation of CDI in these patients can be unique-including diversion colitis,enteritis and pouchitis,and typical findings on colonoscopy are often *** to the high prevalence of CDI in patients hospitalized with an IBD exacerbation,and the prognostic implications of CDI in these patients,it is recommended to test all IBD patients hospitalized with a disease flare for *** includes general measures such as supportive care and infection control *** therapy with either oral metronidazole,vancomycin,or the novel antibiotic-fidaxomicin,should be initiated as soon as *** macrobiota transplantation constitutes another optional treatment for severe/recurrent *** aim of this paper is to review recent data on CDI in IBD:role in pathogenesis,diagnostic methods,optional treatments,and outcomes of these patients.

关键词： Clostridium difficile Diarrhea Inflammatory bowel disease Pathogenesis Treatment

Adsorbents Derived from Xylan Hemicellulose with Removal Properties of Pollutant Metals

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Chinese Journal of Polymer Science 2023年第6期41卷 874-886,I0007页

作者： Elizabeth Elgueta Yerko becerra Ana Martínez Miguel Pereira Isabel Carrillo-Varela Felipe Sanhueza Dariela Nuez BernabéL.Rivas Centro de Investigación de Polímeros Avanzados CIPAAvenida Collao 1202Edificio de LaboratoriosConcepcionChile Departamento de Química Ambiental Facultad de CienciasUniversidad Católica de la Santísima ConcepciónCaila 160-cConcepcionChile Polymer Department Faculty of ChemistryUniversity of ConcepciónCasilla 160-CConcepcionChile Departamento de Ingeniería Química Facultad de IngenieríaUniversidad de ConcepciónConcepcionChile Department of Materials Engineering Faculty of EngineeringUniversidad de ConcepciónConcepcionChile

The adsorption capacity of hydrogels derived from modified xylan hemicellulose has been tested in order to develop new bio-based adsorbent materials useful for removing metal ions pollutants,such as Cd(Ⅱ),Cu(Ⅱ)and Pb(Ⅱ)from an aqueous *** was extracted from bleached kraft pulp of eucalyptus and subsequently modified with different proportions of functional sulfonic acid groups(HA3-HA7)and sulfonate groups(HS30-HS70)to generate *** results showed that all the synthesized hydrogels were capable of adsorbing metal ions,being the hydrogels with 30%and 50%xylan the ones that presented the highest adsorption *** capacity studies at different initial concentrations revealed that at an initial concentration of 300 mg·L-1,the HA3 hydrogel presented an adsorption capacity of 193mg Pb(Ⅱ),182 mg Cd(Ⅱ),and 66 mg Cu(Ⅱ)per g *** HA5 hydrogel presented a capacity of 185 mg Pb(Ⅱ),113 mg Cd(Ⅱ),and 48 mg Cu(Ⅱ)per g *** HS30 hydrogel exhibited an adsorption of 205 mg Pb(Ⅱ),174 mg Cd(Ⅱ),and 71 mg Cu(Ⅱ)per g hydrogel,and HS50 hydrogel exhibited an adsorption capacity of 273 mg Pb(Ⅱ),143 mg Cd(Ⅱ),and 45 mg Cu(Ⅱ)per g *** results show that modified Xylan hemicellulose is a promising adsorbent for removal Cd(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ)ions from aqueous solutions.

关键词： Pb(Ⅱ) solution capacity

Influence of local and landscape environmental factors on alpha and beta diversity of macroinvertebrates in Andean rivers

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Journal of Mountain Science 2023年第9期20卷 2487-2501页

作者： DIAZ-ROJAS Camila A PEDROZA-RAMOS Adriana X BARRERA-herrera July A ROA-FUENTES Camilo A Ecology Unit in Aquatic Systems Research Group Pedagogical and Technological University of ColombiaUPTCAvenida Central del Norte 39-115TunjaBoyacáColombia

Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of alpha and gamma diversity by taking into account environmental predictors at local spatial scales(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of landscape-scale variables have been evaluated to a lesser *** objective of this study was to describe the patterns of alpha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their relationship with local and landscape environmental variation.A stratified random sampling of macroinvertebrates was carried out at 40 sites(comprising an altitudinal range of between 500 and 2900 m.a.s.l.),local and landscape variables were *** results showed that the variation of alpha diversity was influenced by local and landscape variables,which are directly and indirectly related to the contribution of sediments,substrate composition and flow velocity,providing a heterogeneity of *** beta diversity was explained by the combined effect of local and landscape *** the beta diversity phenomena,turnover was predominant while nestedness presented a minor contribution and both were explained in greater proportion by local descriptors and some landscape variables,specifically those of a geomorphological *** results concur with the view of an environmental and spatial hierarchy within the river habitat and highlight the influence of multiple scales on macroinvertebrate *** above suggests that both local and landscape scales must necessarily be considered for environmental management and the conservation of Andean lotic ecosystems.

关键词： Andean lotic systems Andean agroecosystems Instream habitat Landcover Turnover Nestedness