Performance study and efficiency improvement of Hybrid Electric System dedicated to transport application

A Proton Exchange Membrane Fuel Cell (PEMFC) powered Hybrid Electric System (HES) is one of an appreciating research issue for the future due to its high efficiency and capability to use hydrogen as a fuel. The PEMFC cannot sufficiently meet sustained load demands in some cases. For that, to compensate this problem incorporating the slow transient response of the PEMFC, Ultra-capacitors (UCaps) are potential candidates for a solution in this aspect. An adequate Energy management System (EMS) is one essential objective of the researches in this area. Hence, this paper proposed an efficient dynamic model using an energy storage system with the sufficient power capacity to keep the smooth operation of the system. To satisfy the load requirements and optimize the active power flow between hybrid power sources for different modes, the EMS was proposed. This latter was appreciated for its capacity to serve the required power through effective utilization of the PEMFC and UCap. To maximize the system efficiency, the functioning of the system is depending on the decision making and the control of all the system component states. The HES and the control approach are made using Matlab/Simulink environment, from which, the obtained results indicate the reliability and the effectiveness desirability of the HES and its proposed energy management strategy.     

Investigating the diffusional behaviour of Irganox®1076 antioxidant in HDPE/Cloisite®15A nanocomposite‐based food contact packaging films: Effect of nanoclay loading

In this research work, the prediction of the diffusion coefficient (D_p) of Irganox ® 1076 (Ir‐76) antioxidant in HDPE‐based food contact packaging films was carried out. The diffusion of this additive was studied both, in neat HDPE film and in HDPE nanocomposites films made of HDPE matrix filled with 1, 3, and 5 wt% of a commercially available organoclay (Cloisite ® 15A). The diffusion experiments were carried out by using the Roe's method on films consisting of a stack of several polymer films having a total nominal thickness of 120 ± 01 μm. Diffusion coefficients were determined in the temperature range 80°C to 100°C according to the second Fick's law by measuring the evolution of the Ir‐76 concentration in the films by means of Fourier transform infrared (FTIR) spectroscopy analysis. The results indicated that the diffusion coefficient of Ir‐76 in HDPE films decreased with the addition of the organoclay, and a maximum reduction of 78% (at 23°C) in the diffusion rate of the Ir‐76 was observed at an optimum filler content of 3 wt%, thus making these films attractive for the plastic packaging industry.     

New efficient M2C and M2M mutual authentication protocols for IoT-based healthcare applications

Peer-to-Peer Networking and Applications - With the rapid advancement of heterogeneous wireless technologies and their proliferation in ambient connected objects, the Internet of Things (IoT) is a...     

Local repair procedure for carbon‐fiber‐reinforced plastics by refilling with a thermoset matrix

Textile‐reinforced composites have given rise to an increasingly important key technology for lightweight construction in aerospace, automotive, civil engineering, and many other industries. Because there exists no suitable repair procedure for carbon‐fiber‐reinforced plastics (CFRPs), damaged parts have to be replaced completely; this is extremely disadvantageous both ecologically and economically. With fiber‐reinforced composites used being more and more often, fast and efficient methods for the local repair of damaged CFRPs are essential. In this article, a novel repair procedure for CFRP is presented. The thermal activation by IR radiation of oxide semiconductors was used to locally degrade the thermoset matrix of the damaged CFRP through the maintenance of its structural stability and properties. The matrix‐free textile structure was then refilled with a thermoset epoxy matrix. Carbon fibers from the treated area were characterized with scanning electron microscopy, IR spectroscopy, thermogravimetric analysis, and subsequently, tensile strength for single fibers to verify the effectiveness of the procedure. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42964.     

高取代度淀粉醋酸酯合成工艺优化及结构表征

以玉米淀粉为实验材料,在催化剂用量、醋酸与醋酸酐体积比、反应时间、反应温度4个单因素试验基础上,利用响应面试验设计法进行试验设计,获得取代度与各单因素的函数关系,并建立高取代度淀粉醋酸酯合成工艺模型。通过回归方程和响应曲面,得到淀粉醋酸酯最佳合成工艺为催化剂用量0.11mL、醋酸与醋酸酐体积比1:1.39、反应时间1.59h、反应温度87.61℃。验证实验结果显示,在此条件下淀粉醋酸酯取代度为2.95。傅里叶红外光谱分析表明,淀粉醋酸酯葡萄糖单元上的羟基逐渐发生酯化,而且随着取代度测定值升高,乙酰基含量增大。扫描电镜照片显示,淀粉醋酸酯表面变得更为粗糙,孔隙增多且呈蜂窝状,说明酯化反应不仅发生在淀粉颗粒表面,同时也发生在淀粉颗粒内部。     

Comparative study and performance evaluation of central and distributed topologies of photovoltaic system

In this paper, we present a new alternative for improving both the performance of photovoltaic (PV) systems and the efficiency of the energy conversion by using different configuration of power converters. For this purpose, a comparative study between two configurations is carried out. The first configuration consists of a classical PV generator with a single centralized high power converter and the second one concerns a distributed topology. For this latter we use a certain number of PV strings with low power converters attached in series, in parallel or in a combination of series and parallel. Obviously the string topology has some advantages. Each power converter can control the power conversion of each module individually, which results in increased overall energy conversion of the entire system. The MPPT control system in this case can react effectively to atmospheric variations, to shading effect and to changes in the load. The PV system still operates even in case of failure on one of the power converters in a string. We simulated and compared the different conversion configurations in order to find the best one in terms of efficiency and produced energy. The obtained results are very interesting and can lead to optimal sizing and selection of best PV topology for a given application.     

Design of a model powered support system in Kenadsa mine (Algeria)

an increasing use is being made of models for studying powered support system. The main aim of this research work is to design the power support system that is designed for the longwall face which operating in different geological conditions with the use of successfully empirical and modeling technics which takes into account the health of the hydraulics supports, the efficiency of the hydraulic supply system and the cleanliness/load bearing capacity of roof is also suggested, enabling management to ensure that the support system is used at maximum efficiency.     

Properties and reactivity of Zr-incorporated folded sheet mesoporous material for alkylation of anisole using tert-butylalcohol

Zr-incorporated Folded Sheet Mesoporous material (FSM-16) with different Si/Zr ratios = 90, 60, 10 have been synthesized by intercalating kanemite using cetyltrimethylammonium bromide (CTMABr) as the intercalating agent and zirconium sulphate precursors as the zirconium source. The resulting samples were characterized by means of inductively coupled plasma (ICP) technique, XRD, BET, TEM, FT-IR, UV–Vis and a temperature–programmed–desorption (TPD) of pyridine. The effect of the Si/Zr molar ratio on the textural properties of Zr-FSM-16 was investigated. The results reveal that the Zr-FSM-16 was successfully synthesized. The catalytic performance was examined in the vapor phase tert-butylation of anisole with tert-butanol at the temperatures between 423 and 523 K under atmospheric pressure. The results indicate that Zr-FSM-16 (10) was found to be more active than its relatives.The major products are found to be 4-tert-butyl anisole (4-TBA), 2-tert-butyl anisole (2-TBA) and 2,4 di-tert-butyl-anisole (2,4-DTBA). Maximum conversion of anisole is observed at 473 K and decreased after that with increasing temperature. The influence of molar ratio, influence of temperature, weight hourly space velocity (WHSV) and time on stream on the selectivity of products was investigated and the results are discussed.