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Effect of inductively coupled plasma surface treatment on silica gel and mesoporous MCM-41 particles

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Plasma Science and Technology 2018年第6期20卷 104-113页

作者： J A JUAREZ-MORENO U CHACON-ARGAEZ J BARRON-ZAMBRANO C CARRERA-FIGUEIRAS P QUINTANA-OWEN W TALAVERA-PECH Y PEREZ-PADILLA A AVILA-ORTEGA facultad de ingeniería química-uady periférico norte kilómetro 33.5col.chuburna de hidalgo inn C.P. 97203 Mérida Yucatan México centro de investigación y de estudios avanzados del ipn-unidad mérida km.6 antigua carretera a progreso apdo. Postal 73 Cordemex 97310 Méfida Yucatán México

Silica gel and MCM-41 synthesized mesoporous materials were treated with either oxygen（O_2）,hexamethyldisiloxane（HMDSO） and organic vapors like ethanol（Et OH）,and acrylonitrile（AN）inductive *** radiofrequency power for the modification was fixed to 120 W and30 min,assuring a high degree of organic ionization energy in the *** surface properties were studied by infrared spectroscopy（FTIR）,scanning electron microscopy,x-ray photoelectron spectroscopy and dynamic light scattering technique was used for characterizing size *** the silica and MCM-41 particles were modified by AN and HMDSO plasma gases,the surface morphology of the particles was changed,presenting another color,size or *** contrast,the treatments of oxygen and Et OH did not affect the surface morphology of both particles,but increased the oxygen content at the surface bigger than the AN and HMDSO plasma *** this study,we investigated the influence of different plasma treatments on changes in morphology and the chemical composition of the modified particles which render them a possible new adsorbent for utilization in sorptive extraction techniques for polar compounds.

关键词： silica MCM-41 nanoparticles plasma treatment

Oxidative desulfurization of diesel fuel oil using supported Fenton catalysts and assisted with ultrasonic energy

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Petroleum Science 2019年第5期16卷 1176-1184页

作者： Roberto Flores Arturo Rodas Raquel Gasperin facultad de Ciencias Químicas e ingeniería Universidad Autónoma del Estado de MorelosAv.Universidad No.1001Col.Chamilpa62209 CuernavacaMorelosMexico Gerencia de Materiales y Procesos Químicos Instituto Nacional de Electricidad y Energías LimpiasCalle Reforma 113Col.Palmira62490 CuernavacaMorelosMexico

An ultrasound-assisted heterogeneous catalytic oxidation process was applied to eliminate sulfur from commercial diesel fuel *** studied variables were catalyst concentration,type of catalyst(homogeneous or heterogeneous),oxidizing agent concentration,and the application of ultrasound *** catalysts were prepared by impregnation of coal fly ash with an iron(Ⅱ)sulfate aqueous solution using ultrasound *** drying,the catalyst was calcined at 500℃for 4 *** oxidizing agent was hydrogen *** energy was applied with a frequency of 47 kHz and an intensity of 147 *** was employed for extracting the oxidized compounds from the hydrocarbon *** fly ash and ethanol were used with the purpose of applying low-cost raw materials in chemical *** was found that under the studied conditions,increasing oxidizing agent concentration and the application of ultrasound energy can enhance the sulfur removal from commercial diesel fuel *** concentration did not play a significant role in the *** results were obtained using homogeneous or heterogeneous catalyst,which is important since the heterogeneous catalyst could be recovered,reactivated,and used in many cycles.

关键词： Oxidative desulfurization Diesel Ultrasound energy Supported catalyst Low-cost raw materials

Major Existing Classification Matrices and Future Directions for Internet of Things

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Advances in Internet of Things 2017年第4期7卷 112-120页

作者： Kedir Mamo Basher Juan-Ivan Nieto-Hipolito Maria de Los Angeles Cosio Leon Mabel Vazquez-Briseno Juan de Dios Sánchez López Raymundo Buenrostro Mariscal facultad de ingeniería Arquitectura y Dise&#241 o UABC Ensenada México

Classification method is a formula, logical description generalizing characteristics of objects of related area. Nowadays, billions of smart objects are immersed in the environment, sensing, interacting, and cooperating with each other to enable efficient services. When we think about IoT, classification is a major challenge particularly if our technology is international level applicable. So, this limitation needs clear and deep analysis of the existing classification matrixes and gives some future directions depending on the different researches in the area. The paper surveys the current state-of-art in the classification of IoT. First, we try to explain commonly existing classification matrixes;Second, cooperation of different methods defending on classification matrixes used. Then analyses challenges that IoT faced from classification angle and finally we give some direction for future IoT classification.

关键词： Internet of Things Classification of IoT IoT Overview Future of IoT Smart Objects

Analysis of the Performance of a dehulling System for Confectionary Sunflower Seeds

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Food and Nutrition Sciences 2014年第6期5卷 541-548页

作者： Ana Karina de Figueiredo Luciana Marcela Rodríguez Isabel Concepción Riccobene Susana Maria Nolasco facultad de ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires Grupo de Investigación TECSE Departamento de Ingeniería Química Buenos Aires Argentina

Confectionary sunflower, which has a larger size and lower oil content than oilseed sunflower, has a considerable market, since it is used for birdfeed and human consumption. The characteristics of use of confectionary sunflower seeds require a dehulling process that is efficient in the removal of the hull and that also allows obtaining a product consisting mainly of whole kernels. Response surface methodology was used to determine an optimal combination of working conditions in the dehulling process of confectionary sunflower seeds. Optimization factors were impact speed, expressed in terms of the peripheral speed (28.3 -41.9 m/s), and moisture content of the seeds (4% -14%, dry basis—db). A central composite rotatable design (CCRD) was used to develop models for the responses (dehulling ability—DA and percentage of whole kernels—WK). Applying the desirability function method, the optimal values of the factors were determined using maximum WK and maximum DA as criteria. The results of the optimization technique suggest that by dehulling Mycogen 9338 confectionary sunflower seeds at 12.3% db and 32.5 m/s, the maximum values of DA and WK (72.6% and 63%, respectively) would be obtained. The moisture value defined as optimal determines a requirement of humidification of the seeds prior to dehulling, establishing the need for a technical and economic feasibility study.

关键词： Confectionary Sunflower dehulling Response Surface Methodology Whole Kernels

Phase-field modeling of fracture for quasi-brittle materials

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Underground Space 2019年第1期4卷 10-21页

作者： Jacinto Ulloa Patricio Rodríguez Cristóbal Samaniego Esteban Samaniego department of Civil Engineering Katholieke Universiteit LeuvenB-3001 LeuvenBelgium departamento de Recursos Hídricos y Ciencias Ambientales Universidad de CuencaCuenca 010151Ecuador Universidad de Cuenca Cuenca 010151Ecuador Institut für Kontinuumsmechanik Leibniz Universität HannoverHannover 30167Germany Inria Bordeaux-Sud-Ouest Research Center 200 Avenue de la Vieille TourTalence 33405France facultad de ingeniería Universidad de CuencaEcuador

This paper addresses the modeling of fracture in quasi-brittle materials using a phase-field approach to the description of crack *** the computational mechanics community,several studies have treated the issue of modeling fracture using phase *** of these studies have used an approach that implies the lack of a damage *** herein explore an alternative model that includes a damage threshold and study how it compares with the most popular *** formulation is systematically explained within a rigorous variational ***,we present the corresponding three-dimensional finite element discretization that leads to a straightforward numerical *** simulations in two dimensions and three dimensions are then *** results show that while an elastic stage and a damage threshold are ensured by the present model,good agreement with the results reported in the literature can be obtained,where such features are generally absent.

关键词： Quasi-brittle materials Fracture Variational formulation Phase fields Gradient damage

ACE-I inhibitory peptide fractions from enzymatic hydrolysates of velvet bean (<i>Mucuna pruriens</i>)

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Agricultural Sciences 2013年第12期4卷 767-773页

作者： Maira Rubi Segura-Campos Carlos Paul Espadas-Alcocer Luis Chel-Guerrero David Betancur-Ancona facultad de ingeniería Química Universidad Autónoma de Yucatán Mérida México

The hydrolysis of velvet bean (Mucuna pruriens) protein in the presence of Alcalase?-Flavourzyme? and Pepsin-Pancreatin was investigated. The results showed that Alcalase?-Flavourzyme? (29.08%) sequential system catalyzed the hydrolysis most efficiently that Pepsin-Pancreatin (24.78%). In addition, the higher ACE-I inhibitory activity was achieved with the sequential system Alcalase?-Flavourzyme? (33.13%). Furthermore, the concentration of peptides employing an ultrafiltration (UF) system or their purification by gel filtration chromatography showed that the oligomeric peptides with lower molecular weight registered the highest ACE-I inhibitory activity. It has been demonstrated that Mucuna pruriens protein hydrolysates could serve as a source of peptides with ACE inhibitory activity and this activity can be attributed mainly to the mixture of short peptides in the hydrolysate.

关键词： Velvet Bean Mucuna pruriens ACE-I Inhibition Peptide Fractions Enzymatic Hydrolysis

Modelling and simulating Chikungunya spread with an unstructured triangular cellular automata

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Infectious Disease Modelling 2020年第1期5卷 197-220页

作者： Gerardo Ortigoza Fred Brauer Iris Neri facultad de ingeniería Universidad VeracruzanaBoca Del RíoVerMexico Mathematics department University of British ColumbiaVancouverB.CCanada Maestría en Gestion Integrada de Cuencas Universidad Autonoma de QueretaroMexico

In this work we propose a mathematical model to simulate Chikungunya spread;the spread model is implemented in a C++ cellular automata code defined on unstructured triangular grids and space visualizations are performed with *** order to simulate the time space spread of the Chikungunya diseases we include assumptions such as:heterogeneous human and vector densities,population mobility,geographically localized points of infection using geographical information systems,changes in the probabilities of infection,extrinsic incubation and mosquito death rate due to environmental *** experiments reproduce the qualitative behavior of diseases spread and provide an insight to develop strategies to prevent the diseases spread.

关键词： Cellular automata Unstructured triangular grids Chikungunya spread

Evaluation of Residual Stresses Induced by High Speed Milling Using an Indentation Method

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Modern Mechanical Engineering 2012年第4期2卷 143-150页

作者： Felipe Díaz Claudio Mammana Armando Guidobono departamento de ingeniería Electromecánica—departamento de ingeniería Industrial Facultad Regional Rafaela División Metrología Dimensional Centro Regional Rosario (INTI) Rosario Argentina

In this work, a recently developed method based on the change of distance between collinear indents is used to evaluate different states of residual stress, which were generated in samples of AA 6082-T6 and AA 7075-T6 aluminium alloys milled at high speed. One of the advantages of this method, which needs a universal measuring machine, is not requiring neither the use of specific equipment nor highly skilled operators. Also, by integrating an indentation device to the mentioned machine, the absolute error of measurement can be reduced. In results obtained in samples subjected to different cutting conditions it is observed a correlation between the stress values and the depth of cut, showing the AA 6082-T6 alloy higher susceptibility to be stressed. Furthermore, the high sensitivity of the method allowed detecting very small differences in the values reached by different normal components in the zones corresponding to climb and conventional cutting. It is important to note that these differences were similar for both evaluated alloys. Finally, the directions associated with the principal components of residual stress, where maximum local plastic stretching occurs, were found to be strongly dependent on the rolling direction prior to machining.

关键词： Residual Stresses High Speed Milling Indentation Methods Aluminium Alloys Principal Directions

Physicochemical and Functional Characterization of <i>Mucuna pruries</i>depigmented Starch for Potential Industrial Applications

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International Journal of Organic Chemistry 2015年第1期5卷 1-10页

作者： Maira Rubi Segura-Campos Sonia Marina López-Sánchez Arturo Castellanos-Ruelas David Betancur-Ancona Luis Chel-Guerrero facultad de ingeniería Química Universidad Autónoma de Yucatán Mérida México

Starch is a very important biopolymer in the food industry. The velvet bean (M. pruriens) is an excellent potential starch source containing approximately 520 g starch per kg. The objective of this study was to evaluate the physicochemical and functional properties of velvet bean depigmented starch. The starch granules appear oval and spherical shaped. The colour registered L*, a*, b* values of 44.9, 0.324 and 0.341 respectively. The chemical composition registered values of moisture, ash, fat, protein, fibre and NFE of 110.5, 5.8, 5.7, 0.0, 34 and 954.5 g/kg respectively, as well as amylose levels of 215.3 g/kg. Gelatinization onset (To), peak (Tp) and final (Tf) temperatures were of 74.23°C, 80.57°C and 86.39°C. The solubility (3.1% - 16.2%), swelling power (SP) (2.86% - 16.17%) and water absorption capacity (WAC) (2.67 - 15.95 g water/g starch) were directly correlated to temperature (60°C - 90°C). The enthalpy values (4.10 - 13.47 j/g) were directly correlated to the time (1 - 21 days). The retrogradation increased as time increased. The viscosity of M. pruriens depigmented starch decreased slightly during the heating stages and then increased during cooling and the refrigeration and freezing stability registered syneresis ranges from 17.65 to 23.18 mL/50mL and from 16.4 to 22.6 mL/50mL respectively, indicating that the depigmented starch was unstable in heating-cooling processes.

关键词： depigmented Starch Functional Properties Mucuna pruriens Physicochemical Properties