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Preparation and Characterization of Flexible, Transparent and Thermally Stable Aromatic Co-polyamides

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Chinese journal of Polymer Science 2019年第2期37卷 136-141页

作者： josé antonio Tec-Sánchez Andrés Iván Oliva Arias Manuel Aguilar-Vega juan Valerio Cauich-Rodríguez josé Luis Santiago-García Unidad de Materiales Centro de Investigación Científica de Yucatán A. C. Centro de Investigación y de Estudios Avanzados del IPN Unidad Mérida Departamento de Física Aplicada

Two aromatic co-polyamides were synthesized combining two diacid monomers containing bulky pendant groups, 5-(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)isophthalic acid(DEAIA) and 5-tert-butylisophthalic acid(TERT), with 4,4′-(hexafluoroisopropylidene)dianiline(HFA) or 2,3,5,6-tetramethyl-1,4-phenylenediamine(Durene) by direct polycondensation. The structures of the obtained aromatic co-polyamides were confirmed by FTIR, Raman and 1 H-NMR. The co-copolyamide films, DHTH and DDTD, exhibited rms-roughness values between 0.94 and 1.60 nm, respectively. Moreover, they presented good thermal stability up to300 °C. Young's moduli of the co-polyamide films were between 4.1 and 4.3 GPa. X-ray diffraction results showed that the co-polyamide films were amorphous due to the incorporation of both bulky pendant groups, tert-butyl and dibenzobarrelene. The combination of bulky pendant groups provided intrinsically transparent co-polyamide films with a transmittance higher than 88% in the range of 400-780 *** to these outstanding film and optical properties, they are suggested to be flexible substrates in applications for solar cell and other portable electronic devices.

关键词： Co-polyamides Flexible films Transmittance Thermal stability Polycondensation

Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco jairo Soares Pereira antonio Viana da Silva Filho josé Wellington Batista Lopes josé Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(july 2018-july 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

Integral Representation Formulas Related to the Lamé–Navier System

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Acta Mathematica Sinica,English Series 2020年第12期36卷 1341-1356页

作者： Ricardo ABREU-BLAYA juan BORY-REYES Marcos antonio-HERRERA-PELáEZ josé María SIGARRETA-ALMIRA Facultad de Matemáticas Universidad Autónoma de GuerreroGuerreroMéxico Instituto Politécnico Nacional SEPI-ESIME-ZAC CD-MXMéxico

The paper provides integral representations for solutions to a certain first order partial differential equation natural arising in the factorization of the Lamé–Navier system with the help of Clifford analysis *** representations look like in spirit to the Borel–Pompeiu and Cauchy integral formulas both in three and higher dimensional setting.

关键词： Lamésystem Clifford analysis Dirac operator

Seed provenance determines germination responses of Rumex crispus (L.) under water stress and nutrient availability

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journal of Plant Ecology 2019年第6期12卷 949-961页

作者： María Pérez-Fernández Carole PElliott Alex Valentine joséantonio Oyola Ecology Area University Pablo de OlavideCarretera de Utrera Km 141013 SevillaSpain Kings Park Science Botanic Garden and Parks AuthorityDepartment of BiodiversityConservation and AttractionsKattidj CloseKings ParkWA 6005Australia School of Biological Science The University of Western AustraliaCrawleyWA 6009Australia Department of Botany and Zoology Stellenbosch UniversityPrivate Bag X1Matieland 7602South Africa Physics Department University of ExtremaduraAvenida de Elvas s/n06006 BadajozSpain

Aims Seeds of Rumex crispus from six provenances were studied in relation to their germination under drought and presence of nitrogen in the germination and emergence *** also investigated whether adaptation to soil increases the ability of the species to colonize and establish in contrasting environments along a longitudinal gradient in western Spain by means of a reciprocal transplantation *** We conducted a germination trial in the lab to test for the germination responses to water scarcity along a polyethylene glycol gradient and to varying concentrations of nitrogen *** reciprocal transplantations experiment was conducted,where seeds from six provenances were grown in the soils from the very same *** emergence,survivorship and fitness-related variables were measured in all *** Findings We found that *** has a cold-stratification requirement that enhances its *** differences between the six provenances were detected for time-to-germination,total seedling emergence,plant mortality and reproductive effort in all the *** differences between provenances with respect to germination were confirmed by the significant statistical analyses of the variance,thus providing evidence that seeds from parent plants grown in different environmental conditions have an intrinsically different abilities to germinate and *** nitrogen content where seed germination and seedlings establish also play an important role in their performance in terms of survivorship and reproduction,being the higher levels of inorganic nitrogen and of microbial biomass those that increased biomass production,enhanced inflorescence formation and reduced plant *** conclude that one of the main reasons for the spread and maintenance of *** would be the increased levels of nitrogen in agricultural soils.

关键词： seed provenance germination latitudinal gradient drought N-compounds soil properties

Preface:Special Issue on Modeling,Simulation,and Optimization in Operational Research

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journal of the Operations Research Society of China 2022年第4期10卷 685-688页

作者： Gerhard-Wilhelm Weber j.joshua Thomas josé antonio Marmolejo Saucedo Ugo Fiore Igor Litvinchev Pandian Vasant Poznan University of Technology PoznanPoland Institute of Applied Mathematics Middle East Technical UniversityAnkaraTurkey UOW Malaysia KDU Penang University CollegePetaling JayaMalaysia Facultad de Ingeniería Universidad PanamericanaMexico CityMexico Parthenope University and at Federico II University NaplesItaly Nuevo Leon State University San Nicolás de los GarzaMexico MERLIN Research Centre Ton Duc Thang UniversityHo Chi Minh CityVietnam

“Operational Research”(OR)is“the discipline of applying advanced analytical methods to help make better decisions”.By using techniques such as problem structuring methods and mathematical modeling to analyze nontr... 详细信息

关键词： Simulation applying productive

Thermal and salinity effects on locomotor performance of Thoropa taophora tadpoles(Anura,Cycloramphidae)

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Integrative Zoology 2020年第1期15卷 40-54页

作者： antonio C.GALLO Cinthia ABRASILEIRO Fábio Cury DE BARROS joséEduardo DE CARVALHO Department of Ecology and Evolutionary Biology Federal University of São PauloDiademaSão PauloBrazil

It is well known that environmental temperature influences several biological functions of ectotherms,notably in *** high permeability of anuran skin,associated with the effect of elevated environmental temperature,potentiates the dehydration process and this combination may restrict locomotor ***pa taophora is an endemic species from the Atlantic Rainforest whose tadpoles are semiterrestrial and predominantly diurnal,and are found in rocky seashores where they are exposed to sea spray and high *** this study we investigated how temperature and salinity conditions affect the locomotor performance in Thoropa taophora *** also assessed how different osmotic concentrations affect the activity of the metabolic pathways that support muscle *** measured the sprint speed of tadpoles of various sizes at different temperatures and salinities in the *** also measured the activity of the enzymes pyruvate kinase(PK),lactate dehydrogenase(LDH)and citrate synthase(CS)in different temperatures and osmotic concentrations,and calculated the thermal sensitivity and the activity constants for each *** results showed that,in general,sprint speed decreased with increasing temperature and ***,whereas the effect of increased salinity was similar in smaller and larger tadpoles,increased temperature had a higher negative impact on sprint speed of larger tadpoles,thus indicating low thermal sensitivity of small *** and LDH thermal sensitivities and LDH constant of activity decreased as the osmolality *** conclusion,the locomotor capacity of tadpoles was decreased by temperature and salinity,which may be related to a decrease in anaerobic metabolism both in terms of sensitivity and total energy turnover through enzymatic *** discuss the ecological consequences,including the potential impacts on predator escape behavior promoted by changes in metabolism and locomotor performance

关键词： amphibians energy metabolism enzyme activity sprint speed

Kinetic study of austenite formation during continuous heating of unalloyed ductile iron

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International journal of Minerals,Metallurgy and Materials 2015年第1期22卷 27-31页

作者： Octvio Vazquez-Gómez jos antonio Barrera-Godínez Hctor javier Vergara-Hernndez Faculty of Chemistry Metallurgical Engineering DepartmentAutonomous National University of Mexico Metallurgy Science Postgraduate Programme Morelia Institute of Technology

The austenite formation kinetics in unalloyed cast ductile iron was studied on the basis of dilatometry measurements, and Avrami＇s equation was used to estimate the material＇s kinetic parameters. A continuous heating transformation diagram was constructed us-ing heating rates in the range of 0.06 to 0.83℃·s^-1. As the heating rate was augmented, the critical temperatures, c1A and Aα, as well as the intercritical range, which was evaluated as the difference between the critical temperatures, α c1Δ T =A_a- A_c1 , increased. At a low heating rate, the kinetics of austenite formation was slow as a consequence of the iron＇s silicon content. The effect of heating rate on k and n, the kinetic parameters of Avrami＇s equation, was also determined. Parameter n, which is associated with nucleation sites and growth geometry, de-creased with an increase in heating rate. In addition, parameter k increased with the increase of heating rate, suggesting that the nucleation and growth rates are carbon-and silicon-diffusion controlled during austenite formation under continuous heating.

关键词： ductile iron austenite continuous heating heating rate kinetics dilatometry

Performance of statistical and machine learning-based methods for predicting biogeographical patterns of fungal productivity in forest ecosystems

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Forest Ecosystems 2021年第2期8卷 278-291页

作者： Albert Morera juan Martínez de Aragón josé antonio Bonet jingjing Liang Sergio de-Miguel Department of Crop and Forest Sciences University of LleidaAv.Alcalde Rovira Roure 191E-25198 LleidaSpain joint Research Unit CTFC-AGROTECNIO-CERCA Center Av.Rovira Roure 19125198 LleidaSpain Forest Science and Technology Centre of Catalonia Ctra.Sant Llorençde Morunys km 225280 SolsonaSpain Forest Advanced Computing and Artificial Intelligence Laboratory Department of Forestry and Natural ResourcesPurdue UniversityWest LafayetteIN 47907USA

Background:The prediction of biogeographical patterns from a large number of driving factors with complex interactions,correlations and non-linear dependences require advanced analytical methods and modeling *** study compares different statistical and machine learning-based models for predicting fungal productivity biogeographical patterns as a case study for the thorough assessment of the performance of alternative modeling approaches to provide accurate and ecologically-consistent ***:We evaluated and compared the performance of two statistical modeling techniques,namely,generalized linear mixed models and geographically weighted regression,and four techniques based on different machine learning algorithms,namely,random forest,extreme gradient boosting,support vector machine and artificial neural network to predict fungal *** evaluation was conducted using a systematic methodology combining random,spatial and environmental blocking together with the assessment of the ecological consistency of spatially-explicit model predictions according to scientific ***:Fungal productivity predictions were sensitive to the modeling approach and the number of predictors ***,the importance assigned to different predictors varied between machine learning modeling *** tree-based models increased prediction accuracy by more than 10%compared to other machine learning approaches,and by more than 20%compared to statistical models,and resulted in higher ecological consistence of the predicted biogeographical patterns of fungal ***:Decision tree-based models were the best approach for prediction both in sampling-like environments as well as in extrapolation beyond the spatial and climatic range of the modeling *** this study,we show that proper variable selection is crucial to create robust models for extrapolation in biophysically differentiated *** allows for reducing the dime

关键词： Modeling Regression Biogeography Climate Forest Fungi Mushrooms

Visual function,performance,and processing of basketball players *** individuals

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journal of Sport and Health Science 2020年第6期9卷 587-594页

作者： jesús Vera Raimundo jiménez David Cárdenas Beatriz Redondo josé antonio García Department of Optics Faculty of ScienceUniversity of GranadaGranada 18071Spain Department of Physical Education and Sport Faculty of Sport ScienceUniversity of GranadaGranada 18071Spain Sport and Health University Mixed Institute University of GranadaGranada 18071Spain

Background:Athletes tend to have better visuo-motor performance than do sedentary ***,several basic visual-function and perceptual parameters remain unexplored to *** this study,we investigated whether differences exist in visual function,performance,and processing between basketball players and individuals without a sport-involvement ***:A total of 33 healthy men with no visual impairment or pathology were divided into 2 groups,depending on the involvement in sport(semi-professional basketball players and sedentary individuals).We tested their baseline heart-rate variability in the resting position apart from subjective questionnaires to determine their physical fitness level,and we checked their visual function,performance,and processing through an extended battery of optometric ***:The 2 groups differed in resting heart-rate variability parameters(p<0.001),confirming their dissimilarities in regular time practising sports per *** basketball players showed a closer breakpoint and recovery nearpoint of convergence,a higher fusional-vergence rate,better discriminability halos,and better eye-hand coordination(all p values<0.05).Conclusion:These results show evidence that athletes,basketball players in this case,exhibit better performance in several visual abilities in comparison to a group of individuals without sporting backgrounds,suggesting an improvement due to the systematic involvement of those skills during basketball practice.

关键词： Exercise Fitness level Health Heart rate variability Visual skills Team sport