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Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang arturo J.Hernndez-maldonado Zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/M^(n+)-zeolite X(si/Al=1,M^(n+)=Cu^(2+) and Ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor M^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and M^(n+)-zeolite X, and their interactions with M^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on M^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern Zeolite X

Zeolite-templated carbons as effective sorbents to remove methylsiloxanes and derivatives:A computational screening

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Green Energy & Environment 2021年第6期6卷 884-892页

作者： shiru Lin Kaitlyn A.Jacoby Jinxing Gu Dariana R.Vega-santander arturo J.Hernaandez-maldonado Zhongfang Chen Department of Chemistry University of Puerto RicoRío PiedrasSan JuanPR 00931USA Department of Chemistry&Biochemistry Elizabethtown CollegeElizabethtownPA 17022USA Department of Chemical Engineering University of Puerto RicoMayaguez CampusMayaguezPR 00681USA

Though widely used in our daily lives,volatile methylsiloxanes and derivatives are emerging contaminants and becoming a high-priority environment and public health *** effective sorbent materials can remove siloxanes in a cost-effective ***,by means of Grand Canonical Monte Carlo(GCMC)simulations,we evaluated the potentials of the recently proposed 68 stable zeolite-templated carbons(ZTCs)(PNAs 2018,115,E8116-E8124)for the removal of four linear methylsiloxanes and derivatives as well as two cyclic methylsiloxanes by the calculated average loading and average adsorption energy *** ZTCs,namely IsV,FAU1,FAU3,and H8326836,were identified with the top 50%adsorption performance toward all the six targeted contaminants,which outperform activated *** first principles computations revealed that steric hindrance,electrostatic interactions(further enhanced by charge transfer),and CH-p interactions account for the outstanding adsorption performance of these *** work provides a quick procedure to computationally screen promising ZTCs for siloxane removal,and help guide future experimental and theoretical investigations.

关键词： Zeolite-templated carbons Contaminants of emerging concern Methylsiloxanes GCMC simulations Density functional theory calculations

Rapid and robust slope failure appraisal using aerial photogrammetry and 3D slope stability models

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International Journal of Mining science and Technology 2020年第5期30卷 651-658页

作者： Neil Bar Michael Kostadinovski Michael Tucker Glen Byng Rully Rachmatullah arturo maldonado Markus Pötsch Andreas Gaich Alison McQuillan Thamer Yacoub BHP PerthWA 6000Australia 3GsM GmbH 8010 GrazStyriaAustria Rocscience Inc. Toronto M5T 1V1Canada

slope failures are an inevitable aspect of economic pit slope designs in the mining *** open pit guidelines and industry standards accept up to 30%of benches in open pits to collapse provided that they are controlled and that no personnel are at *** ground control measures including real time monitoring systems at TARP(trigger-action-response-plan)protocols are widely utilized to prevent personnel from being exposed to slope failure *** and computing capability are rapidly *** photogrammetry techniques using UAV(unmanned aerial vehicle)enable geotechnical engineers and engineering geologists to work faster and more safely by removing themselves from potential line-of-fire near unstable *** stability modelling software using limit equilibrium(LE)and finite element(FE)methods in three dimensions(3D)is also becoming more accessible,user-friendly and faster to *** key components enable geotechnical engineers to undertake site investigations,develop geotechnical models and assess slope stability faster and in more detail with less exposure to fall of ground hazards in the *** paper describes the rapid and robust process utilized at BHP Limited for appraising a slope failure at an iron ore mine site in the Pilbara region of Western Australia using a combination of UAV photogrammetry and 3D slope stability models in less than a shift(*** than 12 h).

关键词： slope stability 3D limit equilibrium analysis Aerial imagery Photogrammetry Open pit mining

Emerging melt quality control solution technologies for aluminium melt

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China Foundry 2009年第4期6卷 358-365页

作者： arturo Pascual Foseco Foundry(China)Co. Ltd.2002 Leishing International Plaza1319 Yan'an RoadShanghaiChinaJr

The newly developed ＂MTs 1500＂ Melt Treatment system is performing the specifically required melt treatment operations like degassing, cleaning, modification and/or grain refinement by an automated process in one step and at the same location. This linked process is saving time, energy and metal losses allowing - by automated dosage of the melt treatment agents - the production of a consistent melt quality batch after batch. By linking the MTs Metal Treatment system with sensors operating on-line in the melt, i.e., with a hydrogen sensor ＂Alspek H＂, a fully automated control of parts of the process chain like degassing is possible. This technology does guarantee a pre-specified and documented melt quality in each melt treatment batch. Furthermore, to ensure that castings are consistent and predictable there is a growing realization that cdtical parameters such as metal cleanliness must be measured prior to casting. There exists accepted methods for measuring the cleanliness of an aluminum melt but these can be both slow and costly. A simple, rapid and meaningful method of measuring and bench marking the cleanliness of an aluminum melt has been developed to offer the foundry a practical method of measuring melt cleanliness. This paper shows the structure and performance of the integrated MTs melt treatment process and documents achieved melt quality standards after degassing, cleaning, modification and grain refinement operations under real foundry conditions. It also provides an insight on a melt cleanliness measuring device ＂Alspek MQ＂ to provide foundry men better tools in meeting the increasing quality and tighter specification demand from the industry.

关键词： melt quality aluminum casting melt treatment cleanliness measuring

Introduction of Dr. Andrew V schally

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Asian Journal of Andrology 2015年第6期17卷 923-924页

作者： arturo Mendoza-Valdes UROLOGO Hospital Medica Sur Puente dePiedra 150 T2-625 Col. Toriello Guerra Tlalpan14050Mexico DF.

Ifirst met Dr. Andrew V schally （PhD, MDhc （Multi）, Dsc, Distinguished Medical Research scientist, U.s. Department of Veterans Affairs Professor of Pathology and Department of Medicine, Miller school of Medicine, University of Miami, Miami, Florida, UsA） many years ago, probably around the beginning of the 1990＇s in one of his visits to Mexico City （Figure 1）. He has many friends in my country since some of the investigations that led to the development of the LHRH agonists were made in a couple of Mexican hospitals in collaboration with some outstanding Mexican physicians that I will mention later. In that time, I was the head of the Department of Urology of the Mexican National Cancer Institute and our Director, Dr. Jaime de la Garza, invited him for a meeting. I was surprised by his humbleness, intelligence and easy going personality, in spite of being a Nobel Prize scientist.

关键词： Introduction Andrew schally

An Approach to Design MIMO FO Controllers for Unstable Nonlinear Plants

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IEEE/CAA Journal of Automatica sinica 2016年第3期3卷 338-344页

作者： arturo Rojas-Moreno IEEE Department of Electrical Engineering Universidad de Ingenieriay Tecnologia (www.utec.edu.pe)

This paper develops an approach to control unstable nonlinear multi-inputs multi-output(MIMO) square plants using MIMO fractional order(FO) controllers. The controller design uses the linear time invariant(LTI) state space representation of the nonlinear model of the plant and the diagonal closedloop transfer matrix(TM) function to ensure decoupling between inputs. Each element of the obtained MIMO controller could be either a transfer function(TF) or a gain. A TF is associated in turn with its corresponding FO TF. For example, a D(Derivative) TF is related to a FO TF of the form Dδ, δ =[0, 1]. Two applications were performed to validate the developed approach via experimentation: control of the angular positions of a manipulator, and control of the car and arm positions of a translational manipulator.

关键词： Fractional calculus modeling of nonlinear sys-tem control of manipulator multivariable decoupling multivari-able nonlinear system

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

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Frontiers in Energy 2019年第3期13卷 522-538页

作者： Pedro PONCE Therese PEFFER arturo MOLINA Tecnologico de Monterrey calle del puente 222 MexicoMexico CityNon-US/Non-Canadian 64849Mexico California Institute for Energy and Environment University of California BerkeleyBerkeleyCA 94720USA

It is well known that smart thermostats (sTs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable sTs or when they do not use the sTs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the sTs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (sDT), fuzzy detection theory (FDT), and chi-square (Cs) test in order to understand the perceptions and beliefs of end users about the use of sTs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about sTs are not met. It also promotes the technological and social development of sTs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (sDT) fuzzy signal detection theory (FsDT) chi-square (Cs) test

Numerical Approach of a Coupled Pressure-saturation Model Describing Oil-Water Flow in Porous Media

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Communications on Applied Mathematics and Computation 2023年第2期5卷 946-964页

作者： Paula Luna arturo Hidalgo IsIs Neutron and Muon source Rutherford Appleton LaboratoryDidcot OX110QXUK Departamento de Ingeniería Geológica y Minera Escuela Técnica Superior de Ingenieros de Minas y EnergíaCenter for Computational SimulationUniversidad Politécnica de MadridRíos Rosas2128003 MadridSpain

Two-phase flow in porous media is a very active field of research,due to its important applications in groundwater pollution,CO_(2)sequestration,or oil and gas production from petroleum reservoirs,just to name a few of *** flow equations,which make use of Darcy's law,for describing the movement of two immiscible fluids in a porous medium,are among the most relevant mathematical models in reservoir *** work aims to solve a fractional flow model formed by an elliptic equation,representing the spatial distribution of the pressure,and a hyperbolic equation describing the space-time evolution of water *** numerical solution of the elliptic part is obtained using a finite-element(FE)scheme,while the hyperbolic equation is solved by means of two dif-ferent numerical approaches,both in the finite-volume(FV)*** is based on a monotonic upstream-centered scheme for conservation laws(MUsCL)-Hancock scheme,whereas the other makes use of a weighted essentially non-oscillatory(ENO)*** both cases,a first-order centered(FORCE)-αnumerical scheme is applied for inter-cell flux reconstruction,which constitutes a new contribution in the field of fractional flow models describing oil-water movement.A relevant feature of this work is the study of the effect of the parameterαon the numerical solution of the models *** also show that,in the FORCE-αmethod,when the parameterαincreases,the errors diminish and the order of accuracy is more properly attained,as verified using a manufactured solution technique.

关键词： Two-phase flow Reservoir simulation Porous media FORCE-α Finite volume

successes and failures of participation-in-design： Cases from Old Havana, Cuba

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Frontiers of Architectural Research 2017年第3期6卷 401-411页

作者： arturo Valladares school of Urban Planning McGill University Montreal Quebec Canada

Following the fall of the soviet Union, Cuba faced a crisis that forced it to change its housing approach. self-help building programs began to supplant the construction of mass standardized housing estates. The Community Architect Program was developed to provide design advice to self-help builders, and it expanded exponentially within a decade. By the year 2000, all municipalities across Cuba had their own Community Architect Office. White the approach of the Community Architect Program has been hailed a breakthrough in the fields of planning and architecture, the particular case of Old Havana suggests that several obstacles prevent residents from benefiting from its services. The author identifies the strengths and limitations of the approach by looking at two home renovation projects in Old Havana and the perceptions of tow-income residents on the work done by community architects. This research indicates that participatory design methods should be complemented by community-based initiatives that address other aspects of the housing development process, such as access to materials, construction, and construction management.

关键词： Participation-indesign Community archi-tects Historic districts Urban regulations Cuba Caribbean cities