Photovoltaic properties of M-phthalocyanine/fullerene organic solar cells

Photovoltaic devices made from M-phthalocyanine and fullerene have been fabricated and characterized by current–voltage response, lateral time-of-flight photoconductivity, UV-visible absorption and scanning electron microscopy. The effect of varying the central moiety on the photovoltaic performance is examined, and demonstrates that the monovalent and divalent phthalocyanines tend to yield higher efficiencies in blended structures, whereas the trivalent and tetravalent phthalocyanines tend to yield higher efficiencies in a bilayer structure. The apparent reason for the disparity is the measured decrease in the hole transport efficiency in trivalent and tetravalent phthalocyanine upon blending with C₆₀. Furthermore, the open circuit voltages of M-phthalocyanine/fullerene solar cells are grouped together according to the valency of the central moiety.     

Comparison of Linear,Widely Linear and Fresh Equalizers for FBMC-OQAM Systems with Different Numerologies

Wireless Personal Communications - Wireless sensor network (WSN) is a cost-effective networking solution for information updating in the coverage radius or in the sensing region. To record a real...     

Process dependence of BTI reliability in advanced HK MG stacks

Bias temperature instabilities (BTI) reliability is investigated in advanced dielectric stacks. We show that mobility performance and NBTI reliability are strongly correlated and that they are affected by the diffusion of nitrogen species N at the Si interface. PBTI, more sensitive to bulk oxide traps, is strongly reduced in very thin dielectric films. Reducing the metal gate thickness favors the reduction of mobility degradations and NBTI, but, also strongly enhances PBTI, due to a complex set of reactions in the gate oxide. Trade off must be found to obtain a great trade off between device performance and reliability requirements.     

Isolation and characterisation of trypsin from sardinelle (Sardinella aurita) viscera

BACKGROUND: In Tunisia, sardinelle (Sardinella aurita) catches totalled about 13 300 t in 2002. During processing, solid wastes including heads and viscera are generated, representing about 30% of the original raw material. Viscera, one of the most important by‐products of the fishing industry, are recognised as a potential source of digestive enzymes, especially proteases with high activity over a wide range of pH and temperature conditions. This paper describes the purification procedure and some biochemical characterisation of trypsin from S. aurita viscera. RESULTS: Trypsin from the viscera of sardinelle (S. aurita) was purified by fractionation with ammonium sulphate, Sephadex G‐75 gel filtration, Sepharose mono Q anion exchange chromatography, ultrafiltration and a second Sephadex G‐75 gel filtration, resulting in a 5.42‐fold increase in specific activity and 6.1% recovery. The molecular weight of the purified enzyme was estimated to be 24 kDa using size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified enzyme showed esterase‐specific activity on N‐α‐benzoyl‐L ‐arginine ethyl ester (BAEE) that was four times greater than its amidase‐specific activity on N‐α‐benzoyl‐DL ‐arginine‐p‐nitroanilide (BAPNA). The optimal pH and temperature for enzyme activity were pH 8 and 55 °C respectively using BAEE as a substrate. The trypsin kinetic constants K_m and k_cat on BAPNA were 1.67 mmol L^?1 and 3.87 s^?1 respectively, while the catalytic efficiency k_cat/K_m was 2.31 s^?1 L mmol^?1. CONCLUSION: Trypsin was purified from sardinelle (S. aurita) viscera. Biochemical characterisation of S. aurita trypsin showed that this enzyme can be used as a possible biotechnological tool in the fish‐processing and food industries. Copyright © 2008 Society of Chemical Industry     

Two-dimensional hygrothermal transfer in porous building materials

A two-dimensional mathematical model for evaluating the simultaneous heat and moisture migration in porous building materials was proposed. Vapor content and temperature were chosen as the principal driving potentials. The numerical solution was based on the control volume finite difference technique with fully implicit scheme in time. Two validation experiments were developed in this study. The evolution of transient moisture distributions in both one-dimensional and two-dimensional cases was measured. A comparison between experimental results and those obtained by the numerical model proves that they are fully consistent with each other. The model can be easily integrated into a whole building heat, air and moisture transfer model. Another main advantage of the present numerical method lies in the fact that the required moisture transport properties are comparatively simple and easy to determine.     

Developing Ambient Intelligence Systems: A Solution based on Web Services

Enabling the ambient intelligence vision means that consumers will be provided with universal and immediate access to available content and services, together with ways of effectively exploiting them. Concentrating on the software system development aspect, this means that the actual implementation of any ambient intelligence application requested by a user can only be resolved at runtime according to the user's specific situation. This paper introduces a base declarative language and associated core middleware, which supports the abstract specification of Ambient Intelligence applications together with their dynamic composition according to the environment. The proposed solution builds on the Web services architecture, whose pervasiveness enables both services availability in most environments, and specification of applications supporting automated retrieval and composition. In addition, dynamic composition of applications is dealt in a way that enforces the quality of service of deployed applications in terms of security and performance.     

Purification and characterization of phthalocyanines

The technical details of a simple train sublimation (carrier gas) system for purification of organic materials are given and the refining procedure is described. A study of the effects of purification on metal free phthalocyanine (H₂Pc), magnesium phthalocyanine (MgPc), copper phthalocyanine (CuPc), vanadyl phthalocyanine (VOPc), zinc phthalocyanine (ZnPc) and lead phthalocyanine (PbPc) was carried out by means of optical absorption, X-ray diffraction, electron paramagnetic resonance, sublimation behaviour and photovoltaic data. It was found that train sublimation improves the quality of the pigments considerably. Spectroscopic results indicate the presence of a second phase in the purified MgPc.     

Autonomous and adaptive beaconing strategy for multi‐interfaced wireless mobile nodes

Ad hoc wireless communications rely on beaconing to manage and maintain several network operations and to share relevant network parameters among network nodes. Beacon frames are sent at the start of each beacon interval. The frequency of beaconing depends on whether beacon intervals are fixed size or may be adapted and regulated according to the perceived network and workload conditions. On the other hand, current mobile nodes usually embed several heterogeneous wireless interfaces that urge the design of an adaptive beaconing strategy. In this paper, we propose an autonomous and adaptive beaconing strategy for multi‐interfaced mobile wireless nodes that is capable of regulating the beacon interval size dynamically according to the perceived network conditions. The proposed strategy is based on a joint dynamic estimation of both the announcement traffic indication message (ATIM) window and the beyond‐ATIM window sizes for each beacon interval. Extensive simulations were conducted using OMNeT++ to ascertain the improvements achieved by autonomously regulating the entire beacon interval to take into account the network and workload conditions. Obtained results showed that the two proposed approaches improve significantly the efficiency of the network in terms of throughput, end‐to‐end delay, and power consumption. The proposed fixed beacon interval (fixed‐BI) approach stands as an enhanced version of the power‐saving multi‐channel MAC protocol (PSM‐MMAC). The proposed variable beacon interval (variable‐BI) approach, which regulates dynamically both of the ATIM and the beyond‐ATIM windows, outperforms both the fixed‐BI and the PSM‐MMAC. In particular, under nominal traffic loads, the end‐to‐end delay of the variable‐BI is much lower than those provided by the fixed‐BI and PSM‐MMAC. Copyright © 2015 John Wiley & Sons, Ltd.     

Simultaneous heat and moisture transport in porous building materials: evaluation of nonisothermal moisture transport properties

The paper presents a mathematical model for calculating the nonisothermal moisture transfer in porous building materials. The simultaneous heat and moisture transfer problem was modeled. Vapor content and temperature were chosen as principal driving potentials. The coupled equations were solved by a numerical method. An experimental methodology for determining the temperature gradient coefficient for building materials was also proposed. Both the moisture diffusion coefficient and the temperature gradient coefficient for building material were experimentally evaluated. Using the measured moisture transport coefficients, the temperature and vapor content distribution inside building materials were predicted by the new model. The results were compared with experimental data. A good agreement was obtained.     

Monocyte–Macrophage Lineage Cell Fusion

Cell fusion (fusogenesis) occurs in natural and pathological conditions in prokaryotes and eukaryotes. Cells of monocyte–macrophage lineage are highly fusogenic. They create syncytial multinucleated giant cells (MGCs) such as osteoclasts (OCs), MGCs associated with the areas of infection/inflammation, and foreign body-induced giant cells (FBGCs). The fusion of monocytes/macrophages with tumor cells may promote cancer metastasis. We describe types and examples of monocyte–macrophage lineage cell fusion and the role of actin-based structures in cell fusion.