Application of a multicriteria methodology for evaluation of energy alternatives for hydrogen production for the automotive sector – Case study

This paper presents a case study focusing on fourteen most used energy alternatives in Brazil, possible to feed large scale hydrogen production plants for the automotive sector. The evaluations are made using a Decision Making Support Method, MACBETH - Measuring Attractiveness by a Categorical Based Evaluation Technique, with the computational code M-MACBETH 3.2.0, using criteria that include economic and financial, technological, environmental and social aspects. The selected criteria that were used in the assessment, for each of the energy alternatives are capital to be invested in a plant, leveled cost of electric energy produced, CO₂ emissions, mortality rate due to the technology use and energy efficiency of technology. The main results obtained showed that photovoltaics off grid electric energy is the most attractive alternative, followed by the photovoltaic on grid alternative, for an eventual automotive hydrogen program in Brazil.     

A decomposition-based approach for the selection of standardized modular containers

The standardisation of packaging and containers for product handling has potential benefits from transportation, material handling and environmental perspectives. Likewise, standardised modular containers play an important role in the Physical Internet (PI). To support implementation of standard modular containers, we introduce a mathematical model to select a requisite number of modular containers to pack a set of products to maximise space utilisation. A decomposition-based solution methodology is developed and presented. Computational results from industry-based problem instances indicate that using standardised modular containers results in increased space utilisation at the unit load level. This finding substantiates the use of modular containers in moving toward the PI.     

Processing of a natural hydroxyapatite powder: From powder optimization to porous bodies development

This paper deals with the development of macro-porous components made of a carbonated hydroxyapatite (HAp) nanopowder which was extracted from pig bones. Prior to sintering, the powder was treated at 700 °C for 1 h. During calcination, a partial carbonate decomposition occurred yielding CaO. In order to eliminate this by-product, the calcined HAp was washed in distilled water several times, checking the effect of washings by FT-IR spectroscopy. Then, the thermal stability of the as-calcined and washed powders treated in the range 800-1400 °C was investigated by XRD.After that, macro-porous materials made of washed HAp powder were prepared through a modified gelcasting process, using agar as a natural gelling agent and polyethylene spheres as the pore formers.     

Analysis of CLA Isomer Distribution in Nutritional Supplements by Single Column Silver-Ion HPLC

Nutritional supplements containing conjugated linoleic acid (CLA) isomers, widely used to improve body composition and inhibit fat storage, should be thoroughly analyzed, as CLA effects are isomer specific. In this research, an improvement of silver-ion high performance liquid chromatography (Ag⁺-HPLC) was obtained by using a single-column instead of the most commonly used multi-columns. To develop the procedure, a standard CLA mixture has been derivatized with different chain length alcohols (from methanol to hexanol). Hexyl CLA showed better separation between CLA isomer pairs, in particular the resolution of the t10,c12: c9,t11 pair increased from 0.3 (methyl esters) to 0.8 (hexyl esters). Therefore, the CLA isomer composition of some commercial CLA products was determined by Ag⁺-HPLC analysis of hexyl esters. The main isomers in all supplements turned out to be c9,t11-CLA and t10,c12-CLA, the most anti-adipogenic isomer. t8,c10- and c11,t13-CLA were not detected. The nutritional supplements were also analyzed by high resolution gas chromatography of methyl esters to evaluate the fatty acid % composition and total CLA % content. The total CLA ranged from 79.4 to 94.4 %, and the t,t isomer from 1.4 to 7.3 %.     

The Expression of Active CD11b Monocytes in Blood and Disease Progression in Amyotrophic Lateral Sclerosis

Monocytes expressing the inflammation suppressing active CD11b, a beta2 integrin, may regulate neuroinflammation and modify clinical outcomes in amyotrophic lateral sclerosis (ALS). In this single site, retrospective study, peripheral blood mononuclear cells from 38 individuals living with ALS and 20 non-neurological controls (NNC) were investigated using flow cytometry to study active CD11b integrin classical (CM), intermediate (IM) and non-classical (NCM) monocytes during ALS progression. Seventeen ALS participants were sampled at the baseline (V1) and at two additional time points (V2 and V3) for longitudinal analysis. Active CD11b+ CM frequencies increased steeply between the baseline and V3 (ANOVA repeated measurement, p < 0.001), and the V2/V1 ratio negatively correlated with the disease progression rate, similar to higher frequencies of active CD11b+ NCM at the baseline (R = −0.6567; p = 0.0031 and R = 0.3862; p = 0.0168, respectively). CD11b NCM, clinical covariates and neurofilament light-chain plasma concentration at the baseline predicted shorter survival in a multivariable and univariate analysis (CD11b NCM—HR: 1.05, CI: 1.01–1.11, p = 0.013. Log rank: above median: 43 months and below median: 21.22 months; p = 0.0022). Blood samples with the highest frequencies of active CD11b+ IM and NCM contained the lowest concentrations of soluble CD11b. Our preliminary data suggest that the levels of active CD11b+ monocytes and NCM in the blood predict different clinical outcomes in ALS.     

On the Delay of a CNTFET with Undeposited CNTs by Gate Width Adjustment

This paper deals with the performance of a Carbon Nano Tube Field Effect Transistor (CNTFET) in the presence of undeposited CNTs as defects. A simulation-based analysis of delay degradation due to different features (such as chirality and defective CNT distribution) is initially pursued. Two solutions to mitigate the change in delay are proposed; these approaches are based on adjusting the gate width of the CNTFET by lithography (and removing CNTs) as part of the fabrication process. These two methods reduce the average delay and its deviation, respectively. A probabilistic delay analysis is then presented. The performance of the proposed two adjustment methods is evaluated by considering CNT features (such as chirality and defect distribution) deterministically and probabilistically. By deterministic (probabilistic) simulation, the first method reduces on average the delay by 6.968 % (7.811 %) while the deviation is increased (decreased) by 32.444 % (9.788 %). The second method reduces deterministically (probabilistically) on average the deviation by 44.159 % (47.476 %) with 2.166 % (4.409 %) delay reduction.     

A neutronic evaluation of the (Pu–U) and (Am–Pu–U) insertion in a typical fuel of Angra-I

The goal is to evaluate the neutronic behavior when (Pu–U) and (Am–Pu–U) mixed oxide are inserted in a typical cell of a Pressurized Water Reactor (PWR) such as Angra-I. Four types of fuels were studied: (1) MOX fuel enriched at 3.1% and V_m/V_f = 1.15; (2) MOX fuel enriched at 4.5% and V_m/V_f = 1.15; (3) MOX fuel enriched at 4.5% and V_m/V_f = 2.0 and (4) MOX fuel enriched at 4.5%, with 1% of Americium insertion in its composition (62.8% of Am²⁴¹, 0.1% of Am^242m and 37.1% of Am²⁴³) and with V_m/V_f = 2.0. The first case represents the standard state of Angra I, but with Pu. The second case is similar to the first but the enrichment is increased. To evaluate the Americium insertion, a study of the V_m/V_f was made and better results were obtained with V_m/V_f = 2.0 and to compare, this case was too evaluated to (Pu–U) in the third and fourth cases. The idea is to verify the possibility of using these fuels in Angra-I analyzing neutronic parameters such as infinite multiplication factor, hardening spectrum, Boron worth and reactivity temperature coefficients. The results show that it is possible to use all the studied fuels in Angra-I as well as to burn Am inserted in the MOX fuel by a considerable quantity during PWR operation. The WIMS-D5 code was used to perform a simplified neutronic and burnup simulations to evaluate this possibility.     

Indirect estimation of elliptical stable distributions

An indirect estimation approach for elliptical stable distributions is presented. The auxiliary model is another elliptical distribution, the multivariate Student-t distribution. It has parameters that have a one-to-one relationship with those of the elliptical stable, making the proposed indirect approach particularly suitable. The finite sample behaviour of the estimators is analyzed using a comprehensive Monte Carlo study. An application to 27 emerging markets stock indexes concludes the paper.     

F-substituted hydroxyapatite nanopowders: Thermal stability,sintering behaviour and mechanical properties

Fluorine-substituted hydroxyapatites are considered promising materials for bone scaffolding. In this study a systematic investigation on F-half substituted hydroxyapatite (F-HAp, Ca₁₀(PO₄)₆OHF) obtained by precipitation is reported. Results on composition analysis, thermal behaviour, and sinterability are presented for a comparison with the respective pure hydroxyapatite. Samples were characterised by electron microscopy, induced coupled plasma-atomic emission spectroscopy, thermal analysis, infrared spectroscopy, N₂ adsorption measurements, X-ray diffraction and dilatometry. A semicrystalline F-substituted hydroxyapatite powder made up of needle-like nanoparticles was obtained. Notwithstanding that it was thermally stable up to 1300 °C, it was sintered at relatively low temperatures obtaining a very fine microstructure with a relevant nano-porosity, beneficial in view of cell adhesion and in-growth.Hardness, elastic modulus and toughness of produced samples were investigated by Vickers–Knoop microhardness testing. Significant improvements of the mechanical properties were observed for the F-substituted hydroxyapatite, in comparison with pure hydroxyapatite.