Protrusions designs of AFRP to eliminate slippage of bonding adhesive

A presentation of a new innovative smart designs of protrusions in Aramid Fiber Reinforced Polymer (AFRP) which could lead the manufacturing industry of AFRP to a new era. The classic straight AFRP strips has a major disadvantage when externally bonded with other engineering materials using bonding adhesive. When exposed to high temperatures, the bonding adhesive slides causing a weak bondage or a complete debonding in some cases between the AFRP and engineering material surfaces. Thus, the purpose of protrusions in AFRP laminates is to eliminate the slippage of the bonding adhesive between the AFRP strips and other engineering material surfaces. This takes place by eliminating the frictional factor between the surfaces of AFRP laminate and bonded engineering material.

Thin Concrete Overlays with Carbon Reinforcement

In many countries like Germany, concrete pavements are normally built as Jointed Plain Concrete Pavements (JPCP). Due to a lack of alternatives, maintenance of concrete pavements usually requires a replacement of the whole pavement structure, which is labour- and resource-intensive. Therefore, new techniques like the application of thin concrete overlays as a partial repair of deteriorated concrete pavements have been developed. As a major disadvantage of such overlays, the existing joints in the retained concrete bottom-layer have to be transferred in the overlay in order to avoid reflection cracking. When using non-corrosive carbon-textile reinforcement in such concrete overlays, cracks might be distributed more finely, enabling jointless repairs while keeping a thin repair layer. In addition, the bond behaviour between the retained concrete and the applied concrete overlay as well as between the concrete overlay and the textile reinforcement is crucial for a successful repair. In this paper, the basic principles and feasibility of such a repair method are examined. On the one hand, the decisive influencing variables and parameters such as bond behaviour between the concrete layers and the cracking behaviour of the overlay are pointed out and discussed. On the other hand, the evaluated laboratory tests carried out are presented. These include large-scale beams built with an overlay on top of a retained concrete layer, which were subjected to cyclic flexural stress and to a subsequent detailed investigation of the bond behaviour and durability. Furthermore, the crack formation in the overlay was determined by means of tensile and flexural tensile strength tests.

A review on performance of nanofluids in various heat pipe solar collector

Energy from the Sun brings as Solar energy which is abundantly available and utilized for various applications. Owing to the increase in energy demand, having a limit of non-renewable energy sources, more interest is given to Solar energy. One of the most fundamental applications of using Solar energy is a Solar collector. The efficiency of the Solar collector depends upon the fluids used in the Solar collector and thermal performance also can be enhanced by using heat pipes in the Solar collector. Compared to flat plate solar collectors, the major disadvantage of heat loss can be rectified in heat pipe solar collectors. Still, to improve the performance of heat pipe solar collectors, nanofluids can be used instead of base fluids to improve thermal performance. In this review paper, the application of nanofluid in Solar collectors results in the percentage of improvement in heat transfer by nanofluid at optimum condition is discussed. This paper reviewed widely the recent development and upcoming research that can be done to enhance the working of heat pipe Solar collectors using nanofluids.

THE SOY FLOUR AS AN EXTENDER FOR UF AND MUF ADHESIVES IN BIRCH PLYWOOD PRODUCTION

Formaldehyde emission still remains a major disadvantage of widely applied formaldehyde-containing amino resins such as UF (urea-formaldehyde) resin and MUF (melamine-urea-formaldehyde) resin. The compositions of adhesives for plywood manufacturing have to contain a proper extenders in order to adjust their viscosity. Thus, the aim of the study was to investigate the effect of protein-rich soy flour (SF) as the extender for adhesives. The composition of flours and their ability to absorb the formaldehyde were determined. Properties of liquid resins such as gel time, viscosity, pH and solid content were investigated. The possible chemical interaction between the extenders and resins were assessed with the use of FTIR spectroscopy. Plywood panels manufactured using UF and MUF adhesives with the soy flour introduced as the extender in various concentrations were tested in terms of shear strength and formaldehyde release. Studies have shown that soy flour has a favorable composition and formaldehyde-scavenging ability. The addition of SF affected resins properties such as viscosity and gel time but showed no influence on their pH and solid content. FTIR analysis has not explained the chemical interaction between resin and extender. The application of soy flour in the concentration of 15% for UF resin and 10% for MUF resin allowed to produce plywood characterized by improved bonding quality and decreased formaldehyde emission.

Teaching cadaveric laparoscopic anatomy in medical curriculum – An essential learning option

Teaching anatomy to the medical students is shifting from learning the traditional gross anatomy with didactic lectures to learning anatomy by laparoscopic dissection on the cadavers. The open dissection hall teaching is loosing relevance to learning clinical anatomy with laparoscopic dissection live by the medical students. Laparoscopic demonstrations can generate interest in surgery in the students that would otherwise not be possible in the preclinical years. Additional advantages of laparoscopic anatomy learning are improved three-dimensional orientation, increased dexterity and development of team working skills among students. The magnified laparoscopic views and the ability to deeply explore anatomical features to demonstrate the basic anatomy better with full clarity does makes an impression on the young medical students. The major disadvantage is student may feel the lack of pleasure of tactile sensation, of touching the anatomical organs during laparoscopic demonstration.

Anthocyanins: Factors Affecting Their Stability and Degradation

Anthocyanins are secondary metabolites and water-soluble pigments belonging to the phenolic group, with important functions in nature such as seed dispersal, pollination and development of plant organs. In addition to these important roles in plant life, anthocyanins are also used as natural pigments in various industries, due to the color palette they can produce from red to blue and purple. In addition, recent research has reported that anthocyanins have important antioxidant, anticancer, anti-inflammatory and antimicrobial properties, which can be used in the chemoprevention of various diseases such as diabetes, obesity and even cancer. However, anthocyanins have a major disadvantage, namely their low stability. Thus, their stability is influenced by a number of factors such as pH, light, temperature, co-pigmentation, sulfites, ascorbic acid, oxygen and enzymes. As such, this review aims at summarizing the effects of these factors on the stability of anthocyanins and their degradation. From this point of view, it is very important to be precisely aware of the impact that each parameter has on the stability of anthocyanins, in order to minimize their negative action and subsequently potentiate their beneficial health effects.

A 24-sectors direct power control-feedforward neural network method of DFIG integrated to dual-rotor wind turbine

<p class="Abstract">In this work, a 24-sector direct power control (24-sector DPC) of a doubly-fed induction generator (DFIG) based dual-rotor wind turbine (DRWT) is studied. The major disadvantage of the 24-DPC control is the steady-state ripples in reactive and active powers. The use of 24 sectors of rotor flux, a feedforward neural network (FNN) algorithm is proposed to improve traditional 24-sector DPC performance and minimize significantly harmonic distortion (THD) of stator current and reactive/active power ripple. The proposed method is modeled and simulated by using MATLAB/Simulink software under different tests and compared with conventional 24-sector DPC.</p>

An indigenous state-of-the-art High Wind Speed Recording (HWSR) system for coastal meteorological observatories

The continuous and accurate monitoring of wind speed and direction is of utmost importance to weatherman, particularly during the cyclonic storms. Wind monitoring also helps the meteorologists in tracking the cyclone accurately and estimating their devastating potential. One major disadvantage of all the existing wind monitoring and storing systems is their huge consumption of power, and hence are not suitable during cyclonic storms due to mains power supply failure. So an attempt has been made by the authors to design and develop a low cost, low power, more accurate and maintenance free High Wind Speed Recording (HWSR) System for the coastal meteorological observatories along the East and West Coasts of India. One such system after successful field trials have been installed at Meteorological Office, Puri in the Orissa coast, and 19 more stations are proposed along East and West Coasts of India. The system meets the operational accuracy requirements and vector averaging of wind data as recommended by the World Meteorological Organisation (WMO, 1992). The system design aspects and scope for expansion have been presented in this paper.

Bayesian inference of a non-local proliferation model

From a systems biology perspective, the majority of cancer models, although interesting and providing a qualitative explanation of some problems, have a major disadvantage in that they usually miss a genuine connection with experimental data. Having this in mind, in this paper, we aim at contributing to the improvement of many cancer models which contain a proliferation term. To this end, we propose a new non-local model of cell proliferation. We select data that are suitable to perform Bayesian inference for unknown parameters and we provide a discussion on the range of applicability of the model. Furthermore, we provide proof of the stability of posterior distributions in total variation norm which exploits the theory of spaces of measures equipped with the weighted flat norm. In a companion paper, we provide detailed proof of the well-posedness of the problem and we investigate the convergence of the escalator boxcar train (EBT) algorithm applied to solve the equation.

Application of Vegetal Oils in Developing Bioactive Paper-Based Materials for Food Packaging

A major disadvantage of conventional food packaging materials is the difficulty in disposal and recycling, due to their high stability to environmental and thermal stress. The trend now is to develop new eco-friendly food packaging that can substitute fossil fuel derived materials. Cellulose, the main constituent of paper-based food packages, is a favorable starting material for such purpose. In this study we present a new method to obtain bioactive paper based materials suitable for food packaging applications. By combining eco-friendly activation processes (cold plasma or gamma irradiation) and bioactive plant oils (clove essential oil and rosehip seeds vegetal oil) for modification of kraft paper, new materials with antioxidant and antibacterial activity were obtained. The oil-loaded bioactive paper based materials presented increased hydrophobicity (from 97° in the case of kraft paper to 115° for oil-loaded sample) and decreased water adsorption (a one-quarter decrease). Due to differential interactions with the functional groups of plant oils, the modified kraft paper presents different antibacterial and antioxidant properties. Essential clove oil imprinted higher antioxidant activity (owing to the high content in eugenol and eugenol acetate phenolic compounds and were more efficient in reducing the bacterial growth on fresh beef meat and especially on fresh curd cheese. The cold pressed rosehip seeds oil acted as aslightly better antibacterial agent against Listeria monocytogenes (+), Salmonella enteritidis (-) and Escherichia coli (-) bacterial strains. Thus, the newly developed bioactive paper could be used as effective packaging material that can help preserving food quality for longer time.