Evaluation of continuously mixed reactor configurations in the oxidative-adsorptive desulfurization of diesel fuel: Optimization and parametric studies

de Luna, Mark Daniel G.,Futalan, Cybelle M.,Dayrit, Raymond A.,Choi, Angelo Earvin S.,Wan, Meng-Wei Elsevier 2018 Journal of Cleaner Production Vol.203 No.-

<P><B>Abstract</B></P> <P>In this study, oxidative-adsorptive desulfurization technology was applied to raw diesel containing 1480.4 ppm sulfur. For oxidative desulfurization, the oxidant and catalyst were hydrogen peroxide and phosphotungstic acid, respectively. Two types of continuously mixed reactors: (1) continuous stirred tank reactor (CSTR) and (2) in-line mixer were evaluated under varying reaction temperature, mixing speed and diesel flow rate. For the in-line mixer system, the mixer speed and the flow rates for diesel and oxidant were modeled and optimized using Box-Behnken design of the response surface methodology. Optimization of process parameters resulted in sulfur removal of 85.90% at 18,000 rpm mixer speed, 500 mL min<SUP>−1</SUP> diesel flow rate and 300 mL min<SUP>−1</SUP> H<SUB>2</SUB>O<SUB>2</SUB> flow rate. In the subsequent adsorptive desulfurization experiments, continuous fixed-bed adsorption using alumina removed 92.81% sulfur from treated diesel fuel thereby producing low-sulfur diesel that is within the allowable limit of Euro IV standard.</P> <P><B>Highlights</B></P> <P> <UL> <LI> In-line mixer has better removal efficiency of sulfur from diesel over CSTR. </LI> <LI> Oxidative-adsorptive desulfurization achieved 92.81% sulfur removal. </LI> <LI> Oxidative-adsorptive desulfurization achieved residual sulfur of 30 ppm. </LI> </UL> </P>

Optimization and kinetics of the desulfurization of diesel fuel via high shear mixing oxidation assisted by adsorption of sulfones onto chitosan-coated bentonite

De Luna, Mark Daniel G.,Futalan, Cybelle M.,Duavis, Ayesha G.,Wan, Meng-Wei Taylor and Francis 2018 INTERNATIONAL JOURNAL OF GREEN ENERGY Vol.15 No.14

Kinetics of Mixing-Assisted Oxidative Desulfurization of Dibenzothiophene in Toluene Using a Phosphotungstic Acid/Hydrogen Peroxide System: Effects of Operating Conditions

de Luna, Mark Daniel G.,Wan, Meng-Wei,Golosinda, Lucille R.,Futalan, Cybelle M.,Lu, Ming-Chun ACS AMERICAN CHEMICAL SOCIETY 2017 ENERGY AND FUELS Vol.31 No.9

<P>Mixing-assisted oxidative desulfurization (MAOD) of model fuel that contains dibenzothiophene (DBT) using phosphotungstic acid (HPW) as a catalyst and hydrogen peroxide (H2O2) as an oxidant was evaluated. Characterization analysis of HPW shows that the average crystallite size is 82.39 nm, with a disintegrated structure and morphology. The effect of operating parameters, such as mixer speed (5000-10 000 rpm), tetraoctylammoniurn bromide [phase-transfer agent (PTA)]/HPW ratio (0.5:1-5:1), and temperature (25-60 degrees C), on the sulfur conversion of DBT was examined. Results show that the sulfur conversion increases with an increasing temperature and mixer speed and a lower amount of PTA. The highest sulfur removal and rate constant of 100.0% and 0.1528 min(-1), respectively, were attained under the following conditions: 1:1 ratio, 40 degrees C, and 10 000 rpm. The pseudo-first-order equation and Arrhenius equation were applied to determine the kinetic rate constant and activation energy of HPW in the oxidation of DBT in a MAOD system. High correlation coefficient values (R-2 >= 0.93) indicate that the pseudo-first-order equation has the goodness of fit in describing the experimental kinetic data. Moreover, the activation energy of HPW derived from the Arrhenius equation was 42.60 kJ/mol.</P>

Assessment of Nutrient Value and Microbiological Safety of Pomacea lineata

Hilzeth de Luna Freire Pessoˆa,Maria Lu´cia da Conceic¸a˜o,Andrea Maria Rolim da Paz,Bagno´ lia Arau´jo da Silva,Maria Jose´ de Carvalho Costa 한국식품영양과학회 2015 Journal of medicinal food Vol.18 No.7

Pomacea lineata is a fresh water shellfish that is utilized as food, medicinal portions, or licking remedies. The objective of this study was to evaluate the nutritional and microbiological aspects of P. lineata and spawning. The samples were collected in the Jaguaribe River (Paraı´ba, Brazil) during the rainy and dry seasons. The biochemical composition, mineral composition, total mesophilic bacteria (TMB), total coliforms (TC), fecal coliforms (FC), Salmonella sp., Staphylococcus aureus, and Vibrio presence were determined. Each 100 g of P. lineata presented 3.1 g of ashes; 9.4 g of proteins; 2.7 g of lipids; 0.6 g of carbohydrates; 1800.0 mg of calcium; 78.0 mg of phosphorus, and 58.4 mg of iron. Each 100 g of spawning presented 10.4 g of ashes; 4.5 g of proteins; 2.8 g of lipids; 1.3 g of carbohydrates; 3633.0 mg of calcium; 39.4 mg of phosphorus; and 4.6 mg of iron. Each 100 g of P. lineata provided 65.7 kcal and spawning 48.3 kcal. In the dry season P. lineata and spawning showed no TMB and TC, FC, S. aureus, Salmonella, or Vibrio. In the rainy season P. lineata and spawning presented increase in TMB and TC, FC, S. aureus, and Salmonella. The presence of Vibrio was not detected. P. lineata presented proteins, low lipid, and carbohydrate content, energy values close to those of lean meats, high contents of calcium and iron, and presented low contamination level with pathogenic bacteria. Since P. lineata substances may be useful in the treatment of respiratory and gastrointestinal diseases without presenting toxic or cytotoxic effects already described in the literature, it may be considered as a potential functional food.

Health Informatics in Developing Countries: Going beyond Pilot Practices to Sustainable Implementations: A Review of the Current Challenges

Daniel Luna,Alfredo Almerares,John Charles Mayan III,Fernán González Bernaldo de Quirós,Carlos Otero 대한의료정보학회 2014 Healthcare Informatics Research Vol.20 No.1

Objectives: Information technology is an essential tool to improve patient safety and the quality of care, and to reduce healthcare costs. There is a scarcity of large sustainable implementations in developing countries. The objective of this paper is to review the challenges faced by developing countries to achieve sustainable implementations in health informatics and possible ways to address them. Methods: In this non-systematic review of the literature, articles were searched using the keywords medical informatics, developing countries, implementation, and challenges in PubMed, LILACS, CINAHL, Scopus, and EMBASE. The authors, after reading the literature, reached a consensus to classify the challenges into six broad categories. Results: The authors describe the problems faced by developing countries arising from the lack of adequate infrastructure and the ways these can be bypassed; the fundamental need to develop nationwide e-Health agendas to achieve sustainable implementations; ways to overcome public uncertainty with respect to privacy and security; the difficulties shared with developed countries in achieving interoperability; the need for a trained workforce in health informatics and existing initiatives for its development; and strategies to achieve regional integration. Conclusions: Central to the success of any implementation in health informatics is knowledge of the challenges to be faced. This is even more important in developing countries, where uncertainty and instability are common. The authors hope this article will assist policy makers, healthcare managers, and project leaders to successfully plan their implementations and make them sustainable, avoiding unexpected barriers and making better use of their resources.

A novel radioactive particle tracking algorithm based on deep rectifier neural network

Dam, Roos Sophia de Freitas,dos Santos, Marcelo Carvalho,do Desterro, Filipe Santana Moreira,Salgado, William Luna,Schirru, Roberto,Salgado, Cesar Marques Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.7

Radioactive particle tracking (RPT) is a minimally invasive nuclear technique that tracks a radioactive particle inside a volume of interest by means of a mathematical location algorithm. During the past decades, many algorithms have been developed including ones based on artificial intelligence techniques. In this study, RPT technique is applied in a simulated test section that employs a simplified mixer filled with concrete, six scintillator detectors and a¹³⁷Cs radioactive particle emitting gamma rays of 662 keV. The test section was developed using MCNPX code, which is a mathematical code based on Monte Carlo simulation, and 3516 different radioactive particle positions (x,y,z) were simulated. Novelty of this paper is the use of a location algorithm based on a deep learning model, more specifically a 6-layers deep rectifier neural network (DRNN), in which hyperparameters were defined using a Bayesian optimization method. DRNN is a type of deep feedforward neural network that substitutes the usual sigmoid based activation functions, traditionally used in vanilla Multilayer Perceptron Networks, for rectified activation functions. Results show the great accuracy of the DRNN in a RPT tracking system. Root mean squared error for x, y and coordinates of the radioactive particle is, respectively, 0.03064, 0.02523 and 0.07653.

Structural Behavior Estimation of North Caloocan Doctors Hospital for an Imminent 7.2 Magnitude Earthquake

Azotea. Marc Sinan B,De Luna. Emmanuel M,Tiburcio. Rodelio A. 한국방재학회 2016 Journal of Disaster Management Vol.1 No.3

Natural disasters are considered inevitable. However, the damage of which can be mitigated through proper implementation from countermeasures. In the Philippines it was reported by the Philippine Volcanology and Seismology (PHILVOCS) that an ominous 7.2 magnitude earthquake in the second quarter of 2015 will hit the capital region of the country, Manila. A 25 percent estimated damage is assumed to be incurred throughout the region both from public and private infrastructures. The foresighted event led to the materialization of this study which assesses the stability of one hospital, the North Caloocan Doctors Hospital (NCDH), in case of the said earthquake. Moreover, the conducted research determines the potentiality of the structure for Immediate Occupancy (IO) in accordance with the criteria set by ATC-40, a code which contains standards and specifications that was developed by the state of California for the evaluation of seismic performance of existing buildings. Also, emergence of plastic hinges on the support structures were also checked and evaluated. SAP2000 is a 3D modeling software which creates a scaled representation of the building given the required input parameters for the simulation of a nonlinear pushover analysis of the earthquake event. This was used in this research. After the simulation, results were then compared to ATC-40 for the evaluation of its structural performance level and stability. Both the x and y direction of the structure was observed and it showed that the global displacement produced for x and y are 0.199 meters and 0.145 meters, respectively. However, in order to meet the objectives of the study, standards from ATC-40 for IO in terms of displacement should not exceed a value of 0.166 meters in any direction. The output clearly implies that the x-direction exceeded the given value, therefore making the structure not suitable for the level of performance the researchers wanted. Furthermore, during the pushover analysis, plastic hinges were developed under cases of IO and Life Safety (LS) and non on the Collapse Prevention (CP). This positively signifies that the structure, after the impending earthquake would still be safe and readily accessible for many.

Preparation of highly photoluminescent carbon dots from polyurethane: Optimization using response surface methodology and selective detection of silver (I) ion

Dela Cruz, Ma. Ivy S.,Thongsai, Nichaphat,de Luna, Mark Daniel G.,In, Insik,Paoprasert, Peerasak Elsevier 2019 Colloids and surfaces. A, Physicochemical and engi Vol.568 No.-

<P><B>Abstract</B></P> <P>In this study, novel carbon dots were synthesized from polyurethane foam via a one-step pyrolysis method. Polyurethane foam is an interesting precursor for carbon dot synthesis because: (1) polyurethane foam waste generation is alarmingly high and (2) polyurethane is rich in nitrogen content which is important for producing highly photoluminescent carbon dots. The carbon dot synthesis parameters namely acid concentration, reaction time, and reaction temperature were modeled and optimized using Box-Behnken design (BBD) of response surface methodology (RSM). Temperature was found to be the most important parameter affecting the photoluminescence quantum efficiency of the carbon dots. The as-prepared carbon dots in aqueous solution showed a blue-green emission under UV light with a relatively high quantum yield of 33%, agreeing well with the value predicted using the RSM. The carbon dots exhibited distinct selectivity toward silver ion (Ag<SUP>+</SUP>) with a limit of detection of 2.8 μM. The Ag<SUP>+</SUP> contents in real water samples were accurately determined with acceptable repeatability. Based on these results, the RSM is a useful tool for investigating the effects of reaction parameters on the quantum efficiency of carbon dots. Furthermore, pyrolysis was proved to be an effective means for producing label-free, highly photoluminescent carbon dots from polyurethane, enabling new, effective recycling strategy and various potential sensing applications.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Removal of chemical oxygen demand from thin-film transistor liquid-crystal display wastewater using chitosan-coated bentonite: Isotherm, kinetics and optimization studies

Ligaray, Mayzonee,Futalan, Cybelle M.,de Luna, Mark Daniel,Wan, Meng-Wei Elsevier 2018 Journal of cleaner production Vol.175 No.-

<P><B>Abstract</B></P> <P>In this study, real thin-film transistor liquid-crystal display wastewater with an initial chemical oxygen demand (COD) concentration of 1348.00 ppm was treated using chitosan-coated bentonite (CCB). Characterization analysis of the CCB adsorbent was performed using Brunauer-Emmett-Teller surface area analysis, scanning electron microscopy, and Fourier-transform infrared spectrometer. The effect of parameters such as contact time, CCB dosage, pH and temperature on the COD removal was examined. Results show that increasing the contact time and CCB dosage increases COD removal efficiency while no considerable change was observed in removal efficiency with varying temperature and pH. Adsorption experiments showed that the removal of COD using CCB best fits the Langmuir isotherm (<I>R</I> <SUP> <I>2</I> </SUP> ≥ 0.9821) while kinetic data was best described by the pseudo-second order equation (<I>R</I> <SUP> <I>2</I> </SUP> ≥ 0.9980), which implies that chemisorption is the rate-determining step. Thermodynamic studies revealed that adsorption of COD onto CCB was spontaneous, exothermic (ΔH° = 5.95 kJ/mol) and decreased randomness in the system (ΔS° = -0.88 J/mol·K). Optimization studies using response surface methodology with central composite design was performed to determine the operating parameters that would yield the maximum COD removal. It was determined that the optimum conditions of 20.32 h, 0.8 g CCB, pH 4.0, and 30 °C would yield a maximum removal of COD of 73.34%.</P> <P><B>Highlights</B></P> <P> <UL> <LI> COD removal using CCB is spontaneous, exothermic and results to low disorder. </LI> <LI> Maximum COD removal of 73.34% from TFT-LCD wastewater using CCB is attained. </LI> <LI> CCB mass is the most significant factor affecting COD removal from wastewater. </LI> </UL> </P>

Temperature-phased anaerobic co-digestion of sewage sludge and microalgae for enhanced biomethane production

Bondad, Cheassylynne B.,Shin, Jingyeong,de Luna, Mark Daniel G.,Kim, Young Mo Desalination Publications 2018 Desalination and water treatment Vol.120 No.-