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Toughening of Immiscible rPS/SAN Blends by SEBS Elastomers: Properties and Morphology

Journal of Materials Science and Chemical Engineering 2022年第3期10卷 42-62页

作者： Khaled Bedjaoui Rodrigo Navarro Rachida Krache juan lopez valentin Rebeca Herrero Calderon Alberto Fernandez Torres Angel Marcos Fernandez Laboratory Multiphas Polymeric Materials (LMPMP) Faculty of Technology University Ferhat Abbas Setif-1 Setif Algerie Instituto de Ciencia y Tecnologia de Polimeros (CSIC) Department of Fisica de Polimeros Elastomeros y Aplicaciones Energeticas Madrid Spain

In this research, an attempt was made to improve compatibility in a polymer blend composed of incompatible constituents, namely, recycled polystyrene (rPS) and polystyrene-co-acrylonitrile (SAN), through the addition of a compatibilizer. The compatibilizing agent, styrene-ethylenebutadiene-styrene block copolymer (SEBS), was added to the polymer blend in ratios of 5 and 10 wt%. For this purpose, blends of rPS and SAN at different ratios, without and with varying concentrations of compatibilizer, were prepared by melt blending using a co-rotating twin-screwextruder. Mechanical properties including tensile and impact strength, rheological properties (RPA), thermal behaviour (DSC) and morphological characteristics (SEM) were evaluated. According to the results obtained by complex viscosity, the blends behave as a pseudoplastic fluid. The results showed that the addition of SEBS increased the Izod impact strength and the elongation at break and decreased the tensile strength and tensile modulus. rPS/SAN blend modified with SEBS had better mechanical properties than the rPS/SAN alloy. SEM photographs revealed that the SEBS was not only distributed in the SAN phase but also distributed in rPS phase in rPS/SAN/SEBS blend. Furthermore, DSC analysis for blends of rPS/SAN gave a good indication of the improvement on miscibility for most compositions. SEM micrographs of tensile fracture surfaces indicated that the formation of the co-continuous phase and the improvement of interface adhesion are the most important reasons for the excellent tensile properties of the rPS/SAN/SEBS blends. Within the range of analysed compositions, the morphologies investigated by SEM are typical of immiscible blends.

关键词： Recycled Polystyrene SAN Toughening Polymer Blends Rheology

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An unsupervised pattern recognition methodology based on factor analysis and a genetic-DBSCAN algorithm to infer operational conditions from strain measurements in structural applications

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Chinese Journal of Aeronautics 2021年第2期34卷 165-181页

作者： juan Carlos PERAFAN-lopez Julian SIERRA-PEREZ Grupo de Investigacion en Ingenieria Aeroespacial Universidad Pontificia BolivarianaCircular 170-01Medellin 050031Colombia

Structural Health Monitoring(SHM) suggests the use of machine learning algorithms with the aim of understanding specific behaviors in a structural system. This work introduces a pattern recognition methodology for operational condition clustering in a structure sample using the well known Density Based Spatial Clustering of Applications with Noise(DBSCAN) *** methodology was validated using a data set from an experiment with 32 Fiber Bragg Gratings bonded to an aluminum beam placed in cantilever and submitted to cyclic bending loads under 13 different operational conditions(pitch angles). Further, the computational cost and precision of the machine learning pipeline called FA + GA-DBSCAN(which employs a combination of machine learning techniques including factor analysis for dimensionality reduction and a genetic algorithm for the automatic selection of initial parameters of DBSCAN) was measured. The obtained results have shown a good performance, detecting 12 of 13 operational conditions, with an overall precision over 90%.

关键词： Clustering DBSCAN Factor analysis FBGs Pattern recognition Strain field

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Mechanical and natural ventilation systems in a greenhouse designed using computational fluid dynamics

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 1-16页

作者： Jorge Flores-Velazquez juan I.Montero Esteban J.Baeza juan C.lopez Mexican Institute of Water Technology.Paseo Cuauhnáhuac 8532 Col.ProgresoC.P.62550JiutepecMor.Mexico Institut de Recerca i Tecnologia Agroalimentàries 08348Cabrils(Barcelona)Spain IFAPA Centro La Mojonera(Junta de Andalucía) Camino San Nicolás 104745 La MojoneraAlmeríaSpain Fundación Cajamar.Estación Experimental“Las Palmerillas”Autovía del Mediterráneo Km 416 704710El EjidoAlmeríaSpain

The aim of this study was to analyse air exchange and temperature distribution in a greenhouse with combined mechanical and natural ventilation and to design more efficient mechanical ventilation *** this purpose,a computational fluid dynamics(CFD)model of the greenhouse was *** configurations were considered:Configuration 1(mechanical ventilation and closed roof ventilators),Configurations 2 and 3(mechanical ventilation and roof ventilators open 30%and 100%,respectively).After validation,the CFD model was used to improve the design of the greenhouse mechanical ventilation system in each of the three configurations *** greenhouse lengths,28 m,50 m,75 m and 100 m,were used in the *** to fan ventilation only,roof ventilation improved the climate of fan-ventilated greenhouses in terms of the air exchange rate(22%)and climate uniformity because the internal air was mixed better than with mechanical ventilation *** the greenhouse length increased,more advantages were achieved with natural ventilation compared to mechanical *** most configurations,there was a strong linear correlation between temperature gradient and greenhouse *** greenhouse whose regression line had the steepest slope was the one with closed roof *** the fan capacity produced a general reduction in temperature,but the effect was less intense for the greenhouses with open roof *** to box inlet ventilators,an enlarged continuous inlet in the wall opposite the fans increased overall system performance because it eliminated backflow recirculation zones,which are prone to produce high temperatures.

关键词： greenhouse cooling fan ventilation roof ventilators combined ventilation

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Building an interoperable space for smart agriculture

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Digital Communications and Networks 2023年第1期9卷 183-193页

作者： Ioanna Roussaki Kevin Doolin Antonio Skarmeta George Routis juan Antonio lopez-Morales Ethel Claffey Manuel Mora juan Antonio Martinez Institute of Communications and Computer Systems AthensGreece Walton Institute WaterfordIreland Department of Information and Communications Engineering University of MurciaMurciaSpain School of Business Waterford Institute of TechnologyWaterfordIreland R&D Department Odin SolutionsMurciaSpain

The digital transformation in agriculture introduces new challenges in terms of data,knowledge and technology adoption due to critical interoperability issues,and also challenges regarding the identification of the most suitable data sources to be exploited and the information models that must be ***(Building an Interoperable,Data-Driven,Innovative and Sustainable European Agri-Food Sector)addresses these challenges by providing an overarching solution that integrates various heterogeneous hardware and software resources(e.g.,devices,networks,platforms)and enables the seamless sharing of data and knowledge throughout the agri-food *** paper introduces the main concepts of DEMETER and its reference architecture to address the data sharing and interoperability needs of farmers,which is validated via two rounds of 20 large-scale pilots along the DEMETER *** paper elaborates on the two pilots carried out in region of Murcia in Spain,which target the arable crops sector and demonstrate the benefits of the deployed DEMETER reference architecture.

关键词： Smart agriculture Internet of things(IoT) DEMETER Reference architecture Interoperability Agricultural information model(AIM) Pilot validation

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Loss of largest and oldest individuals of the Montpellier snake correlates with recent warming in the southeastern Iberian Peninsula

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Current Zoology 2017年第6期63卷 607-613页

作者： Cosme lopez-CALDERON Monica FERICHE Esmeralda ALAMINOS juan M. PLEGUEZUELOS Department of Zoology Faculty of Biology University of Seville C/Reina Mercedes Seville E-41012 Spain Department of Zoology Faculty of Sciences University of Granada Granada E-18071 Spain

The effects of climate change on organisms are now being extensively studied in many different taxa. However, the variation in body size, usually shrinkage in response to increasing temperature, has received little attention regarding to reptiles. During past periods of global warming, many organisms shrank in size, and current evidence and experiments manipulating temperature have shown a biomass decrease in some organisms with increasing temperatures. Here we test whether the body size of the Montpellier snake Malpolon rnonspessulanus from the southeastern Iberian Peninsula is changing and correlated with the increasing temperature in this region during a 39- year period （1976-2014）. We measured the snout-vent length （SVL） of vouchers in scientific collections to check for trends in adult body size at the population level in relation with temperature, while controlling for the age of the individuals （estimated by skeletochronology, n =141）. Given the great ontogenetic variation in body size of the study species, we categorized age in 3 classes：＂young adults＂（under 5 years old）, ＂intermediate adults＂（from 5 to 7 years old）, and ＂old adults＂（from 8 to 14 years old）. By means of linear mixed models, we found a negative relationship between SVL of ＂old adults＂ and average annual temperature in the region during the lifetime of each individual. Our results indicate that largest and oldest individuals of the Montpellier Snake, that is, males because of strong sexual size dimorphism in this species, disappeared from the study population, and suggest that it occurred in response to rising environmental temperature.

关键词： body shrinkage climate warming differential mortality Malpolon monspessulanus skeletochronology snakes Spain.

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How to rectify the misuse of scientific names in bioscience?

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Chinese Science Bulletin 2014年第13期59卷 1479-1481页

作者： Zi-Min Hu lopez-Bautista juan De-Lin Duan Institute of Oceanology Chinese Academy of Sciences Department of Biological Sciences The University of Alabama

The misuse of scientific names for species of organisms is a widespread and long-standing academic phenomenon;however,its negative impacts to scientific community and the public have been largely overlooked all *** we exemplified two research cases in seaweeds to highlight the extent and dimension of misused scientific names of species in bioscience,and present a few feasible measurements to rectify such a *** ultimate goal is to create a discussion platform and to draw deserved attention of scientific name to taxonomy-related scientists.

关键词：生物科学名称误用纠正生物物种科学家分类学海藻

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Effect of snow on mountain river regimes： an example from the Pyrenees

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Frontiers of Earth Science 2017年第3期11卷 515-530页

作者： Alba SANMIGUEL-VALLELADO Enrique MORAN-TEJEDA Esteban ALONSO-GONZALEZ juan Ignacio lopez-MORENO Pyrenean Institute of Ecology CSIC (Spanish Research Council) Zaragoza Spain Department of Geography University of the Balearic Islands Palma de Mallorca Spain

The purpose of this study was to characterize mountain river regimes in the Spanish Pyrenees and to assess the importance of snow accumulation and snowmelt on the timing of river flows. Daily streamflow data from 9 gauging stations in the Pyrenees were used to characterize river regimes. These data were analyzed by hydrological indices, with a focus on periods when snow accumulation and snowmelt occurred. These results were combined with data on Snow Water Equivalent （SWE）（from measure- ments of depth and density of snow in the main river basins and also simulated by a process-based hydrological model）, snowmelting （simulated by a process-based hydrological model）, precipitation （from observations）, and temperature （from observations）. Longitude. and elevation gradients in the Pyrenees explain the transition of river regimes from those that mostly had low nival signals （in the west and at low elevations） to those that mostly had high nival signals （low winter runoff and late spring peakflow, in the east and at high elevations）. Although trend analyses indicated no statistically signifi- cant changes, there was a trend of decreased nival signal over time in most of the analyzed rivers. Our results also demonstrated that snow processes cannot explain all of the interannual variability of river regimes, because the temporal distribution of liquid precipitation and tempera- ture play key roles in hydrography.

关键词： river regime precipitation snow indices,Spanish Pyrenees streamflow

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Spectral response of spider mite infested cotton:Mite density and miticide rate study

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International Journal of Agricultural and Biological Engineering 2013年第1期6卷 48-52页

作者： Yubin Lan Huihui Zhang W C Hoffmann Jr.juan D lopez United States Department of Agriculture Agricultural Research ServiceAreawide Pest Management Research UnitCollege StationTexasUSA United States Department of Agriculture Agricultural Research ServiceWater Management Research UnitParlierCaliforniaUSA

Two-spotted spider mites are important pests in many agricultural *** mites(Acari:Tetranychidae)have been found to cause economic damage in corn,cotton,and *** glass vial bioassays indicate that Temprano™(abamectin)is the most toxic technical miticide for adult two-spotted spider *** an aerial application standpoint,additional research is needed to identify aerial application parameters for this *** objective of this study was to investigate spectral response of spider mite-infested cotton plants with different density levels of mites and treated with different rates of *** showed significantly different spectral signatures of cotton plants infested with different density levels of *** treating mite-infested cotton plants with five different Temprano rate treatments(control,one-eighth,one-fourth,one-half,and full rates),spectral reflectance curves were found to be significantly *** wavelengths of 550 nm,560 nm,680 nm and 740 nm were important for detecting the spectral differences among mite infested cotton plants treated with various rate of *** Difference Vegetative Index imagery was able to detect different levels of cotton plant ***-rate application of Temprano controlled mite-infested plants as effectively as the full-rate *** findings may lead to reduced cost and quantity of miticides used to maintain effective crop production and protection.

关键词： spectral reflectance infested cotton plants crop protection Normalized Difference Vegetative Index(NDVI) Temprano rate treatments

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Chemical modifications of proteins and their applications in metalloenzyme studies

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Synthetic and Systems Biotechnology 2021年第1期6卷 32-49页

作者： Nathchar Naowarojna Ronghai Cheng juan lopez Christina Wong Lu Qiao Pinghua Liu Department of Chemistry Boston UniversityBostonMA02215United States

Protein chemical modifications are important tools for elucidating chemical and biological functions of *** strategies have been developed to implement these modifications,including enzymatic tailoring reactions,unnatural amino acid incorporation using the expanded genetic codes,and recognition-driven *** technologies have been applied in metalloenzyme studies,specifically in dissecting their mechanisms,improving their enzymatic activities,and creating artificial enzymes with non-natural ***,we summarize some of the recent efforts in these areas with an emphasis on a few metalloenzyme case studies.

关键词： Metalloenzymes Biorthogonal reactions Protein engineering Non-canonical amino acids Biocatalysis

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Regulation of the New Arabidopsis Imprinted Gene AtBMIIC Requires the Interplay of Different Epigenetic Mechanisms

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Molecular Plant 2012年第1期5卷 260-269页

作者： Fabian Bratzel ChaoYang Alexandra Angelova Gema lopez-Torrejon Marcus Koch juan Carlos del Pozo Myriam Calonje Centre for Organismal Studies Heidelberg Department of Biodiversity and Plant Systernatics University of Heidelberg Im Neuenheirner Feld 345 69120 Heidelberg Germany Centro de Biotecnologia y Genomica de Plantas （UPM-INIA） Campus de Montegancedo s/n Boadilla del Monte 28660 Madrid Spain

Recently, it has been shown that plants contain homologs to the animal Polycomb repressive complex I （PRC1） components BM11 and RINGIA/B. In Arabidopsis, there are three BMIl-like genes, two of which, AtBMIIA and B, are required during post-embryonic plant growth to repress embryonic traits and allow cell differentiation. However, little is known about the third BMIl-like gene, AtBMIIC. In this work, we show that AtBMIIC is only expressed during endosperm and stamen development. AtBMIIC is an imprinted gene expressed from the maternal allele in the endosperm but bialleli- cally expressed in stamen. We found that the characteristic expression pattern of AtBMIIC is the result of a complex epigenetic regulation that involves CG DNA methylation, RNA-directed non-CG DNA methylation （RdDM）, and PcG activity. Our results show the orchestrated interplay of different epigenetic mechanisms in regulating gene expression throughout development, shedding light on the current hypotheses for the origin and mechanism of imprinting in plant endosperm.

关键词： Epigenetics gene silencing development Polycomb Group proteins.

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