Poly‐3‐hexylthiophene doped with iron disulfide nanoparticles for hybrid solar cells

In this work, the pyrite crystalline phase of iron disulfide nanoparticles (FeS₂) about 20 to 30 nm was obtained by a two‐pot thermal method at 220°C. Subsequently, different concentrations of these nanoparticles were used as a doping agent for the conjugated poly‐3‐hexylthiophene (P3HT). The electrical resistivity of P3HT was decreased almost three orders of magnitude while adding FeS₂ nanoparticles as doping, and dichlorobenzene solvent was a determinant factor for the dispersion of polymer with nanoparticles. Doped‐P3HT dichlorobenzene solution was spin coated onto the FTO/TiO₂ substrate to fabricate the FTO/TiO₂/P3HT:FeS₂/C‐Au hybrid solar cells. Moreover, the power conversion efficiency (PCE) of hybrid devices was studied as a function of pyrite FeS₂ nanoparticle concentration. The highest efficiency of 0.83% was obtained at 1% concentration of FeS₂ nanoparticles. Hence, the results revealed that the FeS₂ nanoparticles could be considered as an alternative charge carrier to develop the bulk hybrid solar cells.     

麦卡伦公寓楼 美国波士顿

正设计麦克伦公寓楼需要重新评估住宅类型,以便在符合开发商要求的前提下,获得一种创新型和可持续性建筑。该建筑全面整合了结构、机电和可持续性等各个方面,因而成为美国波士顿首个获得LEED认证的多户型建筑。该建筑场地位于高速公路出口、住宅区和工业区之间,通过调整建设规模和城市配置来解决与周边建筑物的协调问题。该建筑物的交错桁架系统允许采用灵活多样的单元类型,从而为144个单元的住户     

Multiband Flexible Antenna for Wearable Personal Communications

Wireless Personal Communications - In this paper the design and experimental characterization of a coplanar waveguide-feed planar inverted F antenna for wearable personal communications are...     

Cyberbullying impacts on victims’ satisfaction with information and communication technologies: The role of Perceived Cyberbullying Severity

This study aims to understand how individuals’ perceptions of the severity of cyberbullying they endure affects their experience with the Information and Communication Technology (ICT) medium through which cyberbullying occurs. To this end, it proposes a theoretical model based on Transactional Theory of Stress and Coping and Expectation-Confirmation Theory. A survey-based study involving 115 cyberbullying victims is employed to empirically validate the proposed model. Results indicate that victims’ perceptions of the severity of a cyberbullying episode negatively impact their satisfaction with ICT. Implications of these results for academics and practitioners are discussed and directions for future research are outlined.     

Creep behavior modeling of silica fume containing Al2O3-MgO refractory castables

Alumina-magnesia refractory castables usually present silica fume in their compositions, due to their ability to induce better flowability and to compensate the expansion related to the in situ spinel formation. In this paper, four compositions containing distinct silica fume content (0-1 wt%) were designed and analyzed by creep resistance and hot mechanical strength. The θ-projection concept coupled with the thermodynamic simulations were used in order to predict the creep behavior and to identify the main mechanism leading to the deformation of the samples. Based on the collected results, a linear correlation between the creep parameters (θ_i) and the silica fume content was attained by analyzing the experimental data, resulting in reliable data and the likelihood to simulate the performance of other compositions in the same system. Moreover, particle sliding assisted by viscous flow was suggested as the dominant creep mechanism in the studied castables.     

Is the contextual information relevant in text clustering by compression?

Usually, when analyzing data that have not been processed or filtered yet, it can be observed that not all the data have equal importance. Thus, it is common to find relevant data surrounded by non relevant one. This occurs when analyzing textual information due to its intrinsic nature: texts contain words that provide a lot of information about the subject matter, whereas they contain other words with a little meaning or relevance. We believe that although in principle the non-relevant words are not as important as the relevant ones, the former constitute the substrate that supports the last. Since this substrate is the context that surrounds the relevant information, we call it the contextual information. In this paper, we analyze the relevance that the contextual information has in textual data, in a clustering by compression scenario. We generate the contextual information applying a distortion technique previously developed by the authors. One of the main characteristics of this technique is that it maintains the contextual information. In this paper we compare this technique with three new distortion techniques that destroy the contextual information in different ways. The experimental results support our hypothesis that the contextual information is relevant at least in the area of text clustering by compression.