Photocatalyst TiO2–Co: the effect of doping depth profile on methylene blue degradation

In this work, we study the effect of doping depth profile on the photocatalytic and surface properties of TiO₂ films. Two thin film layers of TiO₂ (200 nm) and Co (5 nm), respectively, were deposited by physical evaporation on glass substrate. These films were annealed for 1 s at 100 and 400 °C and the Co layer was removed by chemical etching. Atomic force microscopy (AFM) phase images showed changes in the surface in function of thermal treatment. The grazing-incidence X-ray fluorescence (GIXRF) measurements indicated that the thermal treatment caused migration of Co atoms to below the surface, the depths found were between 19 and 29 nm. The contact angle showed distinct values in function of the doped profile or Co surface concentration. The UV–vis spectra presented a red shift with the increasing of thermal treatment. Photocatalytical assays were performed by methylene blue discoloration and the higher activity was found for TiO₂–Co treated at 400 °C, the ESI-MS showed the fragments formed during the methylene blue decomposition.     

Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as the temporal capacity of the back-up system. These plants can work like a conventional power plant and compete in the energy stock market avoiding intermittence in electricity production.This work presents a comparisons of statistical models based on time series applied to predict half daily values of global solar irradiance with a temporal horizon of 3 days. Half daily values consist of accumulated hourly global solar irradiance from solar raise to solar noon and from noon until dawn for each day. The dataset of ground solar radiation used belongs to stations of Spanish National Weather Service (AEMet). The models tested are autoregressive, neural networks and fuzzy logic models. Due to the fact that half daily solar irradiance time series is non-stationary, it has been necessary to transform it to two new stationary variables (clearness index and lost component) which are used as input of the predictive models. Improvement in terms of RMSD of the models essayed is compared against the model based on persistence. The validation process shows that all models essayed improve persistence. The best approach to forecast half daily values of solar irradiance is neural network models with lost component as input, except Lerida station where models based on clearness index have less uncertainty because this magnitude has a linear behaviour and it is easier to simulate by models.     

Cr and Zr/Cr nitride CAE-PVD coated aluminum bipolar plates for polymer electrolyte membrane fuel cells

In this work, two nitride coatings deposited on aluminum-based bipolar plates via cathodic arc evaporation physical vapor deposition (CAE-PVD) have been evaluated using two different techniques. The coating materials, a multi-layer chromium-zirconium nitride (ZrN–CrN) and a monolayer chromium nitride (CrN) have been exposed to electrochemical polarization tests for corrosion resistance simulating the typical environment in the anode and cathode sides in polymer electrolyte membrane fuel cells (PEMFC). Besides, two 3-cell PEMFC stacks, one per each coating material, have been formed. The migration of metal cations toward both the gas diffusion layers (GDL) and catalyst layers have been analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), after 100 h of continuous operation of the stacks. Results have shown that the two coatings applied over the Al-plates satisfy the corrosion resistance requirements in the short-term tests performed at the two stacks. Moreover, results obtained from electrochemical polarization tests have revealed that the CrN-coating confers a good corrosion resistance to the Al-based metal plate, achieving values of corrosion potential and corrosion current two orders of magnitude lower than the ones obtained for the Al alloy as-received.     

Historiography of psychology in Brazil: Pioneer works, recent developments.

The evolution of the historiography of psychology in Brazil is surveyed, to describe how the field has evolved from the seminal works of the pioneer, mostly self-taught, psychologists, to the now professional historians working from a variety of theoretical models and methods of inquiry. The first accounts of the history of psychology written by Brazilians and by foreigners are surveyed, as well as the recent works made by researchers linked to the Work Group on the History of Psychology of the Brazilian Association of Research and Graduate Education in Psychology and published in periodicals such as Memorandum and Mnemosine. The present historiography focuses mainly the relationship of psychological knowledge to specific social and cultural conditions, emphasizing themes such as women's participation in the construction of the field, the development of psychology as a science and as a profession in education and health, and the development of psychology as an expression of Brazilian culture and of the experience of resistance of local communities to domination. To reveal this process of identity construction, a cultural historiography is an important tool, coupled with methodological pluralism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

阿塞洛米塔尔图巴朗钢铁集团火花发射光谱法优化氮的分析

近年来,钢铁行业需求量快速上升,竞争也变得更加激烈。为了得到性能可靠的产品,钢铁车间在生产工艺方面需要进一步严格控制好产品的生产规格。在这种背景下,为了严格控制好生产工艺的密封性并保证产品所期望的特性（尤其是其韧性和机械加工性方面）,精确地进行氮的分析必不可少。 在过去几年中, 经典燃烧技术（CC）已广泛应用于鉴定钢中的碳、硫和氮元素。而火花发射法因其性能改进、耗材成本（燃烧技术方面）降低以及在分析时间缩短等方面的优势,也在氮分析方面得到了应用,并且应用越来越广泛。本项研究的目的在于通过火花发射光谱仪（OES）对氮分析进行优化。研究是在巴西塞拉的阿塞洛米塔尔图巴朗钢铁集团的化学分析实验室进行,利用 DMAIC方法学（一种用于改进生产工艺质量的研究方法）^［1］,对潜在的影响因素（包括漂移、样品和周期）进行了分析,并确定和优化了影响氮分析精度的根本原因。在实施该计划后,对结果的精度（基于内标物的标准偏差）和准确性（通过与OE认证的参考物质和力可交叉核验结果进行比较）进行了评估。在本研究项目之前,通过光发射法测得的氮元素的标准偏差高达0.004 0%。阿塞洛米塔尔图巴朗钢铁集团利用光谱仪完成所有的研究计划后,试验表明,其测定标准偏差低达0.000 5%,充分展现了该技术的潜力。本研究对这一标准偏差进行了监测,频率为每周一次,监测期为3个月。结果发现,该标准偏差在0.000 3%到0.000 5%之间波动,表明稳定性较好。由此可见,火花发射光谱技术是氮分析的一种较有前途的方法。     

Towards the development of technical specifications for the production of lithium–lead alloys for the ITER HCLL TMB

The ITER and DEMO projects are developing new Test Blanket Modules (TBM), where the Pb–Li alloy plays a key role in the new commercial fusion reactors functionality. The Breeding Blanket (BB) has to perform several functions which are essential for the reactor operation. The HCLL TBM is one of the Breeding Blanket concepts to be tested in ITER. It is cooled by He and uses the eutectic liquid metal LLE (Lithium–Lead Eutectic) as breeder material (enriched at 90% in ⁶Li).Pb–Li eutectic alloy has no known uses outside of fusion technology, so the available databases of this material are currently incomplete. It is very important, within the material specifications, to have a complete characterization in order to define their chemical and physical properties, because any variation in the alloy composition has significant consequences in their behaviour, and therefore in their regenerative function inside the blanket.The chemical characterization methodology developed and presented in this paper (useful for both Pb–Li alloys as any Pb alloy) is a key tool that allows performing standard quality control procedures for base material and/or monitoring the alloy during the reactor operation. This report provides a procedure to perform a wide material chemical characterization, assessing the concentrations of major elements, as well as a review of trace level elements that can be found both in the eutectic alloy and in starting materials. In this determination plays an important role the ICP-MS technique because, as a highly sensitive technique, allows very low detection limits.     

Biovalorization of brewers’ spent grain for the production of laccase and polyphenols

Brewers’ spent grain (BSG) is the main solid by‐product of the brewing process and is typically disposed of as cattle feed. In this study, BSG was evaluated as a substrate for the production of polyphenols and the lignin‐degrading enzyme laccase using fungal solid‐state fermentation by Trametes versicolor. Laccases are finding increasing applications in the food industry and polyphenols have benefits for human health. After 14 days of fermentation with T. versicolor, there was a 3.4‐fold increase in the extraction of total polyphenols compared with untreated BSG. Using BSG as the sole source of carbon and nitrogen, maximum laccase activity was achieved after seven days of treatment with an activity of 560 U/L. Based on these results, BSG is suggested to be a good lignocellulose waste material to produce value‐added products such as the enzyme laccase and polyphenols. Copyright © 2018 The Institute of Brewing & Distilling