Advances in the knowledge of the double perovskites derived from the conformation and substitution of the material Sr2MgMoO6-δ as anode with potential application in SOFC cell

Regardless of the manufacturing process such as solid-state reaction, sol-gel, etc., applied in obtaining anodes in solid oxide fuel cells (SOFCs), Sr₂MgMoO_6-δ (SMMO) double perovskites are recognized worldwide and widely used as anodic material with potential application in SOFC. This is due to several factors such as high electronic conductivity, high electrocatalytic activity, structural stability under reducing atmosphere, high transition temperature, giant magnetoresistance, reasonable tolerance to carbon formation, and its desired ability to reduce sulfur poisoning. In this review article, the advances of the SMMO double perovskite are analyzed.     

Coated stainless steels evaluation for bipolar plates in PEM water electrolysis conditions

Proton exchange membrane water electrolysis (PEMWE) is a promising technology to be incorporated in the production of green hydrogen, but one of its limitation to market penetration is the cost of bipolar plates (BPP).Aiming to reduce the cost of PEMWE stack, different surface engineered coating systems based on CrN/TiN, Ti/TiN, Ti and TiN deposited by physical vapor deposition on SS 316L, SS 904L and SS 321 were tested, as potential cost effective solutions to be implemented on bipolar plates. A corrosion evaluation has been carried out in anodic PEMWE conditions in order to determine the best substrate/coating combination for bipolar plates. Ti/TiN multi-layered coating on SS 321 shown the best performance with ?0.02% weight loss, current at 2 V_SHE to 436 μA cm^?2 and ICR after corrosion test to 9.9 mΩ cm².     

Do software and video game firms share location patterns across cities? Evidence from Barcelona,Lyon and Hamburg

The Annals of Regional Science - The aim of this paper is to analyse common location patterns of software and video game (SVE) industry and the related agglomeration processes with other creative...     

Minimization of spectral pattern changes during HRMAS experiments at 37 degrees celsius by prior focused microwave irradiation

Object

High-resolution magic angle spinning (HRMAS) magnetic resonance spectroscopy provides detailed metabolomic information from intact tissue. However, long acquisition times and high rotation speed may lead to time-dependent spectral pattern changes, which may affect proper interpretation of results. We report a strategy to minimize those changes, even at physiological recording temperature.

Materials and methods

Glioblastoma (Gbm) tumours were induced in 12 mice by stereotactic injection of GL261 cells. Animals were sacrificed and tumours were removed and stored in liquid N₂. Half of the samples were exposed to focused microwave (FMW) irradiation prior to HRMAS while the other half was not. Time-course experiments (374?min at 37°C, 9.4T, 3,000?Hz spinning rate) were carried out to monitor spectral pattern changes. Differences were assessed with Unianova test while post-HRMAS histopathology analysis was performed to assess tissue integrity.

Results

Significant changes (up to 1.7 fold) were observed in samples without FMW irradiation in several spectral regions e.g. mobile lipids/lactate (0.90–1.30?ppm), acetate (1.90?ppm), N-acetyl aspartate (2.00?ppm), and Choline-containing compounds (3.19–3.25?ppm). No significant changes in the spectral pattern of FMW-irradiated samples were recorded.

Conclusion

We describe here a successful strategy to minimize spectral pattern changes in mouse Gbm samples using a FMW irradiation system.     

Simulation studies on gax based Kalina cycle for both power and cooling applications

A detailed parametric analysis is carried out on both simple and GAX based combined power and cooling cycle. The effect of various parameters such as heat source temperature, refrigeration temperature, sink temperature, split ratio (refrigerant flow ratio between power and cooling systems), split factor (solution flow ratio between absorber and GAX heat exchanger) on the performance of the cycle is studied. The results of the analysis show that using the GAX heat exchanger about 20% of internal heat is recovered within the cycle. The optimum split factor is 0.8–0.9 and the split ratio is 0.5:0.5. The maximum combined thermal efficiency of 35–45% and coefficient of performance of about 0.35 is attained at the optimum conditions.     

A Survey of Cryptographic Primitives and Implementations for Hardware-Constrained Sensor Network Nodes

In a wireless sensor network environment, a sensor node is extremely constrained in terms of hardware due to factors such as maximizing lifetime and minimizing physical size and overall cost. Nevertheless, these nodes must be able to run cryptographic operations based on primitives such as hash functions, symmetric encryption and public key cryptography in order to allow the creation of secure services. Our objective in this paper is to survey how the existing research-based and commercial-based sensor nodes are suitable for this purpose, analyzing how the hardware can influence the provision of the primitives and how software implementations tackles the task of implementing instances of those primitives. As a result, it will be possible to evaluate the influence of provision of security in the protocols and applications/scenarios where sensors can be used.

Kinetic study of ethyl octyl ether formation from ethanol and 1‐octanol on Amberlyst 70

An option to introduce bioethanol to diesel, improving at the same time its fuel quality, is by adding ethyl octyl ether (EOE). It can be obtained successfully by the dehydration reaction between ethanol and 1‐octanol over acidic ion‐exchange resins. In the present work, the kinetic study of EOE synthesis on Amberlyst 70 in the liquid phase is performed in a 20‐cm³ fixed‐bed reactor and in a 100‐cm³ batch reactor at 423–463 K and 2.5 MPa. EOE synthesis takes place together with diethyl ether (DEE) formation as main side reaction. A mechanistic kinetic model in terms of component activities is proposed for EOE synthesis (E_a=105 ± 4 kJ/mol) and for DEE formation (E_a =100 ± 5 kJ/mol). Reaction rates were highly inhibited by the adsorption of the formed water on Amberlyst 70. The inhibitor effect of water is well represented as a competitive adsorption with alcohols reactants on the catalysts surface. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2918–2928, 2014     

Influence of humidity,temperature, and the addition of activated carbon on the preparation of cellulose acetate membranes and their ability to remove arsenic from water

Several composite membranes have been prepared from cellulose triacetate (CTA) and activated carbon (AC) by solvent casting, varying temperature from 35 to 55°C and relative humidity (RH): 10–70%. Some conditions promoted AC particle agglomeration which is evidenced by SEM and IFME^® program. In those membranes, where homogeneity is attained, a deep characterization has been carried out by DMA, MDSC, thermoporometry, solute transport, and AFM. When AC is added in films, T_g is lowered and the fraction of pores with bigger size is augmented. Molecular weight cut off calculated by solute transport, increases from 801.15 to 1194.29 kDa using 1% AC at RH 70% and T 35°C. Water flux is of 5.23 Lm^?2 h^?1 bar^?1. Arsenic removal has been performed, achieving a 45% tested from a 500 ppb arsenic solution, where several factors such as electrical rejection, adsorption and exclusion, could contribute to the total membrane nanofiltration process. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40134.     

Biological dosimetry and Bayesian analysis of chromosomal damage in thyroid cancer patients

Chromosomal damage was investigated in lymphocytes of thyroid cancer patients after radioiodine treatment. An assay on micronuclei (MN) in binucleated cells was performed in blood samples of 25 patients 3 d after (131)I (3.7 GBq) was given. Statistical analysis does not show overdispersion of the MN distribution, thus considering the exposure to blood as being homogeneous (p < 0.05). A dose-protraction factor (G) of 0.1 was considered into the calculation of the blood dose to take into account the effect of the duration of exposure. The total MN count is a sum of the background distribution and the Poisson distribution induced by radiation exposure. A Bayesian approach was used to avoid inconsistencies when the total count was close to or lower than the background level. Estimated blood dose after 3 d of exposure was 0.73 Gy (0.197 mGy/MBq). The usefulness of the Bayesian method in analysing chromosomal damage when the count is low has been determined.     

Single dispersive gradient-index profile for the aging human lens

We provide a single gradient-index (GRIN) profile for the crystalline lens in an updated age-dependent emmetropic-eye model. The parameters defining the GRIN profile include their variation with age and the dispersion of the refractive index in order to account for the increase in the positive-wave spherical aberration, for the constant chromatic difference in the refraction of the human eye, as well as for the decrease in the retinal-image quality with aging. In accounting for these ocular properties, the results show that first, the value of the dispersion parameters are invariant with age. Second, those parameters defining the distribution of the lens index cause the lens-center-index value to decrease slightly, and its position along the lens axis changes with age. Furthermore, these findings are in agreement with the lens paradox.